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46,178 | 22 | Title: Reference Capabilities for Flexible Memory Management: Extended Version
Abstract: Verona is a concurrent object-oriented programming language that organises all the objects in a program into a forest of isolated regions. Memory is managed locally for each region, so programmers can control a program's memory use by adjusting objects' partition into regions, and by setting each region's memory management strategy. A thread can only mutate (allocate, deallocate) objects within one active region -- its"window of mutability". Memory management costs are localised to the active region, ensuring overheads can be predicted and controlled. Moving the mutability window between regions is explicit, so code can be executed wherever it is required, yet programs remain in control of memory use. An ownership type system based on reference capabilities enforces region isolation, controlling aliasing within and between regions, yet supporting objects moving between regions and threads. Data accesses never need expensive atomic operations, and are always thread-safe. | [] | Train |
46,179 | 18 | Title: Ternary Instantaneous Noise-based Logic
Abstract: One of the possible representations of three-valued instantaneous noise-based logic is proposed. The third value is an uncertain bit value, which can be useful in artificial intelligence applications. There is a forth value, too, that can represent a non-existing bit (vacuum-state) that is the same (1 numeric value) for all bits, however that is a squeezed state common for all bits. Some logic gates are explored. A ternary Universe has a significant advantage compared to the standard binary one: its amplitude is never zero during any clock period. All the known binary logic gates work for the binary bit values in the same way as earlier therefore the former binary algorithms can be run in the ternary system with no change and without the problems posed by zero values of the Universe. | [
33994
] | Test |
46,180 | 25 | Title: On the Audio-visual Synchronization for Lip-to-Speech Synthesis
Abstract: Most lip-to-speech (LTS) synthesis models are trained and evaluated under the assumption that the audio-video pairs in the dataset are perfectly synchronized. In this work, we show that the commonly used audio-visual datasets, such as GRID, TCD-TIMIT, and Lip2Wav, can have data asynchrony issues. Training lip-to-speech with such datasets may further cause the model asynchrony issue -- that is, the generated speech and the input video are out of sync. To address these asynchrony issues, we propose a synchronized lip-to-speech (SLTS) model with an automatic synchronization mechanism (ASM) to correct data asynchrony and penalize model asynchrony. We further demonstrate the limitation of the commonly adopted evaluation metrics for LTS with asynchronous test data and introduce an audio alignment frontend before the metrics sensitive to time alignment for better evaluation. We compare our method with state-of-the-art approaches on conventional and time-aligned metrics to show the benefits of synchronization training. | [] | Train |
46,181 | 16 | Title: Video Frame Interpolation with Densely Queried Bilateral Correlation
Abstract: Video Frame Interpolation (VFI) aims to synthesize non-existent intermediate frames between existent frames. Flow-based VFI algorithms estimate intermediate motion fields to warp the existent frames. Real-world motions' complexity and the reference frame's absence make motion estimation challenging. Many state-of-the-art approaches explicitly model the correlations between two neighboring frames for more accurate motion estimation. In common approaches, the receptive field of correlation modeling at higher resolution depends on the motion fields estimated beforehand. Such receptive field dependency makes common motion estimation approaches poor at coping with small and fast-moving objects. To better model correlations and to produce more accurate motion fields, we propose the Densely Queried Bilateral Correlation (DQBC) that gets rid of the receptive field dependency problem and thus is more friendly to small and fast-moving objects. The motion fields generated with the help of DQBC are further refined and up-sampled with context features. After the motion fields are fixed, a CNN-based SynthNet synthesizes the final interpolated frame. Experiments show that our approach enjoys higher accuracy and less inference time than the state-of-the-art. Source code is available at https://github.com/kinoud/DQBC. | [] | Validation |
46,182 | 16 | Title: Gated Self-supervised Learning For Improving Supervised Learning
Abstract: In past research on self-supervised learning for image classification, the use of rotation as an augmentation has been common. However, relying solely on rotation as a self-supervised transformation can limit the ability of the model to learn rich features from the data. In this paper, we propose a novel approach to self-supervised learning for image classification using several localizable augmentations with the combination of the gating method. Our approach uses flip and shuffle channel augmentations in addition to the rotation, allowing the model to learn rich features from the data. Furthermore, the gated mixture network is used to weigh the effects of each self-supervised learning on the loss function, allowing the model to focus on the most relevant transformations for classification. | [] | Validation |
46,183 | 5 | Title: Adaptive Collective Responses to Local Stimuli in Anonymous Dynamic Networks
Abstract: We develop a framework for self-induced phase changes in programmable matter in which a collection of agents with limited computational and communication capabilities can collectively perform appropriate global tasks in response to local stimuli that dynamically appear and disappear. Agents reside on graph vertices, where each stimulus is only recognized locally, and agents communicate via token passing along edges to alert other agents to transition to an"aware"state when stimuli are present and an"unaware"state when the stimuli disappear. We present an Adaptive Stimuli Algorithm that is robust to competing waves of messages as multiple stimuli change, possibly adversarially. Moreover, in addition to handling arbitrary stimulus dynamics, the algorithm can handle agents reconfiguring the connections (edges) of the graph over time in a controlled way. As an application, we show how this Adaptive Stimuli Algorithm on reconfigurable graphs can be used to solve the foraging problem, where food sources may be discovered, removed, or shifted at arbitrary times. We would like the agents to consistently self-organize using only local interactions, such that if the food remains in position long enough, the agents transition to a gather phase, collectively forming a single large component with small perimeter around the food. Alternatively, if no food source has existed recently, the agents should self-induce a switch to a search phase in which they distribute themselves randomly throughout the lattice region to search for food. Unlike previous approaches to foraging, this process is indefinitely repeatable. Like a physical phase change, microscopic changes such as the deletion or addition of a single food source triggers these macroscopic, system-wide transitions as agents share information about the environment and respond locally to get the desired collective response. | [] | Validation |
46,184 | 24 | Title: Unsupervised Detection of Behavioural Drifts with Dynamic Clustering and Trajectory Analysis
Abstract: Real-time monitoring of human behaviours, especially in e-Health applications, has been an active area of research in the past decades. On top of IoT-based sensing environments, anomaly detection algorithms have been proposed for the early detection of abnormalities. Gradual change procedures, commonly referred to as drift anomalies, have received much less attention in the literature because they represent a much more challenging scenario than sudden temporary changes (point anomalies). In this paper, we propose, for the first time, a fully unsupervised real-time drift detection algorithm named DynAmo, which can identify drift periods as they are happening. DynAmo comprises a dynamic clustering component to capture the overall trends of monitored behaviours and a trajectory generation component, which extracts features from the densest cluster centroids. Finally, we apply an ensemble of divergence tests on sliding reference and detection windows to detect drift periods in the behavioural sequence. | [] | Train |
46,185 | 27 | Title: Adaptive Gravity Compensation Control of a Cable-Driven Upper-Arm Soft Exosuit
Abstract: This paper proposes an adaptive gravity compensation (AGC) control strategy for a cable-driven upper-limb exosuit intended to assist the wearer with lifting tasks. Unlike most model-based control techniques used for this human-robot interaction task, the proposed control design does not assume knowledge of the anthropometric parameters of the wearer's arm and the payload. Instead, the uncertainties in human arm parameters, such as mass, length, and payload, are estimated online using an indirect adaptive control law that compensates for the gravity moment about the elbow joint. Additionally, the AGC controller is agnostic to the desired joint trajectory followed by the human arm. For the purpose of controller design, the human arm is modeled using a 1-DOF manipulator model. Further, a cable-driven actuator model is proposed that maps the assistive elbow torque to the actuator torque. The performance of the proposed method is verified through a co-simulation, wherein the control input realized in MATLAB is applied to the human bio-mechanical model in OpenSim under varying payload conditions. Significant reductions in human effort in terms of human muscle torque and metabolic cost are observed with the proposed control strategy. Further, simulation results show that the performance of the AGC controller converges to that of the gravity compensation (GC) controller, demonstrating the efficacy of AGC-based online parameter learning. | [] | Train |
46,186 | 16 | Title: Computation-efficient Deep Learning for Computer Vision: A Survey
Abstract: Over the past decade, deep learning models have exhibited considerable advancements, reaching or even exceeding human-level performance in a range of visual perception tasks. This remarkable progress has sparked interest in applying deep networks to real-world applications, such as autonomous vehicles, mobile devices, robotics, and edge computing. However, the challenge remains that state-of-the-art models usually demand significant computational resources, leading to impractical power consumption, latency, or carbon emissions in real-world scenarios. This trade-off between effectiveness and efficiency has catalyzed the emergence of a new research focus: computationally efficient deep learning, which strives to achieve satisfactory performance while minimizing the computational cost during inference. This review offers an extensive analysis of this rapidly evolving field by examining four key areas: 1) the development of static or dynamic light-weighted backbone models for the efficient extraction of discriminative deep representations; 2) the specialized network architectures or algorithms tailored for specific computer vision tasks; 3) the techniques employed for compressing deep learning models; and 4) the strategies for deploying efficient deep networks on hardware platforms. Additionally, we provide a systematic discussion on the critical challenges faced in this domain, such as network architecture design, training schemes, practical efficiency, and more realistic model compression approaches, as well as potential future research directions. | [
33984,
35821,
12398
] | Train |
46,187 | 24 | Title: Evolving Semantic Prototype Improves Generative Zero-Shot Learning
Abstract: In zero-shot learning (ZSL), generative methods synthesize class-related sample features based on predefined semantic prototypes. They advance the ZSL performance by synthesizing unseen class sample features for better training the classifier. We observe that each class's predefined semantic prototype (also referred to as semantic embedding or condition) does not accurately match its real semantic prototype. So the synthesized visual sample features do not faithfully represent the real sample features, limiting the classifier training and existing ZSL performance. In this paper, we formulate this mismatch phenomenon as the visual-semantic domain shift problem. We propose a dynamic semantic prototype evolving (DSP) method to align the empirically predefined semantic prototypes and the real prototypes for class-related feature synthesis. The alignment is learned by refining sample features and semantic prototypes in a unified framework and making the synthesized visual sample features approach real sample features. After alignment, synthesized sample features from unseen classes are closer to the real sample features and benefit DSP to improve existing generative ZSL methods by 8.5\%, 8.0\%, and 9.7\% on the standard CUB, SUN AWA2 datasets, the significant performance improvement indicates that evolving semantic prototype explores a virgin field in ZSL. | [
915
] | Train |
46,188 | 24 | Title: MaxFloodCast: Ensemble Machine Learning Model for Predicting Peak Inundation Depth And Decoding Influencing Features
Abstract: Timely, accurate, and reliable information is essential for decision-makers, emergency managers, and infrastructure operators during flood events. This study demonstrates a proposed machine learning model, MaxFloodCast, trained on physics-based hydrodynamic simulations in Harris County, offers efficient and interpretable flood inundation depth predictions. Achieving an average R-squared of 0.949 and a Root Mean Square Error of 0.61 ft on unseen data, it proves reliable in forecasting peak flood inundation depths. Validated against Hurricane Harvey and Storm Imelda, MaxFloodCast shows the potential in supporting near-time floodplain management and emergency operations. The model's interpretability aids decision-makers in offering critical information to inform flood mitigation strategies, to prioritize areas with critical facilities and to examine how rainfall in other watersheds influences flood exposure in one area. The MaxFloodCast model enables accurate and interpretable inundation depth predictions while significantly reducing computational time, thereby supporting emergency response efforts and flood risk management more effectively. | [] | Validation |
46,189 | 34 | Title: Detection of Common Subtrees with Identical Label Distribution
Abstract: Frequent pattern mining is a relevant method to analyse structured data, like sequences, trees or graphs. It consists in identifying characteristic substructures of a dataset. This paper deals with a new type of patterns for tree data: common subtrees with identical label distribution. Their detection is far from obvious since the underlying isomorphism problem is graph isomorphism complete. An elaborated search algorithm is developed and analysed from both theoretical and numerical perspectives. Based on this, the enumeration of patterns is performed through a new lossless compression scheme for trees, called DAG-RW, whose complexity is investigated as well. The method shows very good properties, both in terms of computation times and analysis of real datasets from the literature. Compared to other substructures like topological subtrees and labelled subtrees for which the isomorphism problem is linear, the patterns found provide a more parsimonious representation of the data. | [] | Validation |
46,190 | 24 | Title: How To Overcome Confirmation Bias in Semi-Supervised Image Classification By Active Learning
Abstract: Do we need active learning? The rise of strong deep semi-supervised methods raises doubt about the usability of active learning in limited labeled data settings. This is caused by results showing that combining semi-supervised learning (SSL) methods with a random selection for labeling can outperform existing active learning (AL) techniques. However, these results are obtained from experiments on well-established benchmark datasets that can overestimate the external validity. However, the literature lacks sufficient research on the performance of active semi-supervised learning methods in realistic data scenarios, leaving a notable gap in our understanding. Therefore we present three data challenges common in real-world applications: between-class imbalance, within-class imbalance, and between-class similarity. These challenges can hurt SSL performance due to confirmation bias. We conduct experiments with SSL and AL on simulated data challenges and find that random sampling does not mitigate confirmation bias and, in some cases, leads to worse performance than supervised learning. In contrast, we demonstrate that AL can overcome confirmation bias in SSL in these realistic settings. Our results provide insights into the potential of combining active and semi-supervised learning in the presence of common real-world challenges, which is a promising direction for robust methods when learning with limited labeled data in real-world applications. | [
14521
] | Train |
46,191 | 4 | Title: A Zero-Knowledge Revocable Credential Verification Protocol Using Attribute-Based Encryption
Abstract: We introduce a zero-knowledge credential verification protocol leveraging on Ciphertext Policy Attribute-Based Encryption. The protocol supports revocation through cryptographic accumulators. | [] | Train |
46,192 | 27 | Title: Graceful User Following for Mobile Balance Assistive Robot in Daily Activities Assistance
Abstract: Numerous diseases and aging can cause degeneration of people's balance ability resulting in limited mobility and even high risks of fall. Robotic technologies can provide more intensive rehabilitation exercises or be used as assistive devices to compensate for balance ability. However, With the new healthcare paradigm shifting from hospital care to home care, there is a gap in robotic systems that can provide care at home. This paper introduces Mobile Robotic Balance Assistant (MRBA), a compact and cost-effective balance assistive robot that can provide both rehabilitation training and activities of daily living (ADLs) assistance at home. A three degrees of freedom (3-DoF) robotic arm was designed to mimic the therapist arm function to provide balance assistance to the user. To minimize the interference to users' natural pelvis movements and gait patterns, the robot must have a Human-Robot Interface(HRI) that can detect user intention accurately and follow the user's movement smoothly and timely. Thus, a graceful user following control rule was proposed. The overall control architecture consists of two parts: an observer for human inputs estimation and an LQR-based controller with disturbance rejection. The proposed controller is validated in high-fidelity simulation with actual human trajectories, and the results successfully show the effectiveness of the method in different walking modes. | [] | Test |
46,193 | 16 | Title: High Fidelity Image Synthesis With Deep VAEs In Latent Space
Abstract: We present fast, realistic image generation on high-resolution, multimodal datasets using hierarchical variational autoencoders (VAEs) trained on a deterministic autoencoder's latent space. In this two-stage setup, the autoencoder compresses the image into its semantic features, which are then modeled with a deep VAE. With this method, the VAE avoids modeling the fine-grained details that constitute the majority of the image's code length, allowing it to focus on learning its structural components. We demonstrate the effectiveness of our two-stage approach, achieving a FID of 9.34 on the ImageNet-256 dataset which is comparable to BigGAN. We make our implementation available online. | [] | Train |
46,194 | 24 | Title: Learning from Aggregated Data: Curated Bags versus Random Bags
Abstract: Protecting user privacy is a major concern for many machine learning systems that are deployed at scale and collect from a diverse set of population. One way to address this concern is by collecting and releasing data labels in an aggregated manner so that the information about a single user is potentially combined with others. In this paper, we explore the possibility of training machine learning models with aggregated data labels, rather than individual labels. Specifically, we consider two natural aggregation procedures suggested by practitioners: curated bags where the data points are grouped based on common features and random bags where the data points are grouped randomly in bag of similar sizes. For the curated bag setting and for a broad range of loss functions, we show that we can perform gradient-based learning without any degradation in performance that may result from aggregating data. Our method is based on the observation that the sum of the gradients of the loss function on individual data examples in a curated bag can be computed from the aggregate label without the need for individual labels. For the random bag setting, we provide a generalization risk bound based on the Rademacher complexity of the hypothesis class and show how empirical risk minimization can be regularized to achieve the smallest risk bound. In fact, in the random bag setting, there is a trade-off between size of the bag and the achievable error rate as our bound indicates. Finally, we conduct a careful empirical study to confirm our theoretical findings. In particular, our results suggest that aggregate learning can be an effective method for preserving user privacy while maintaining model accuracy. | [] | Validation |
46,195 | 16 | Title: Prior-RadGraphFormer: A Prior-Knowledge-Enhanced Transformer for Generating Radiology Graphs from X-Rays
Abstract: The extraction of structured clinical information from free-text radiology reports in the form of radiology graphs has been demonstrated to be a valuable approach for evaluating the clinical correctness of report-generation methods. However, the direct generation of radiology graphs from chest X-ray (CXR) images has not been attempted. To address this gap, we propose a novel approach called Prior-RadGraphFormer that utilizes a transformer model with prior knowledge in the form of a probabilistic knowledge graph (PKG) to generate radiology graphs directly from CXR images. The PKG models the statistical relationship between radiology entities, including anatomical structures and medical observations. This additional contextual information enhances the accuracy of entity and relation extraction. The generated radiology graphs can be applied to various downstream tasks, such as free-text or structured reports generation and multi-label classification of pathologies. Our approach represents a promising method for generating radiology graphs directly from CXR images, and has significant potential for improving medical image analysis and clinical decision-making. | [] | Train |
46,196 | 16 | Title: Inventing painting styles through natural inspiration
Abstract: We propose two procedures to create painting styles using models trained only on natural images, providing objective proof that the model is not plagiarizing human art styles. In the first procedure we use the inductive bias from the artistic medium to achieve creative expression. Abstraction is achieved by using a reconstruction loss. The second procedure uses an additional natural image as inspiration to create a new style. These two procedures make it possible to invent new painting styles with no artistic training data. We believe that our approach can help pave the way for the ethical employment of generative AI in art, without infringing upon the originality of human creators. | [
45104,
27059,
41084
] | Validation |
46,197 | 16 | Title: Scaling Vision-Language Models with Sparse Mixture of Experts
Abstract: The field of natural language processing (NLP) has made significant strides in recent years, particularly in the development of large-scale vision-language models (VLMs). These models aim to bridge the gap between text and visual information, enabling a more comprehensive understanding of multimedia data. However, as these models become larger and more complex, they also become more challenging to train and deploy. One approach to addressing this challenge is the use of sparsely-gated mixture-of-experts (MoE) techniques, which divide the model into smaller, specialized sub-models that can jointly solve a task. In this paper, we explore the effectiveness of MoE in scaling vision-language models, demonstrating its potential to achieve state-of-the-art performance on a range of benchmarks over dense models of equivalent computational cost. Our research offers valuable insights into stabilizing the training of MoE models, understanding the impact of MoE on model interpretability, and balancing the trade-offs between compute performance when scaling VLMs. We hope our work will inspire further research into the use of MoE for scaling large-scale vision-language models and other multimodal machine learning applications. | [
10624,
19652,
21125,
36786,
23575,
25048,
41146
] | Train |
0 | 0 | Argument in Multi-Agent Systems Multi-agent systems research is concerned both with the modelling of human and animal societies and with the development of principles for the design of practical distributed information management systems. This position paper will, rather than examine the various dierences in perspective within this area of research, discuss issues of communication and commitment that are of interest to multi-agent systems research in general. 1 Introduction A computational society is a collection of autonomous agents that are loosely dependent upon each other. The intentional stance [12] is often taken in describing the state of these agents. An agent may have beliefs, desires, intentions, and it may adopt a role or have relationships with others. Thus, multi-agent systems (MAS) as with most AI research is signi cantly inuenced, at least in its vocabulary, by philosophy and cognitive psychology. 1 So, what's the point? Computational societies are developed for two primary reasons: Mode... | [
1260
] | Train |
1 | 1 | Decomposition in Data Mining: An Industrial Case Study Data mining offers tools for discovery of relationships, patterns, and knowledge in large databases. The knowledge extraction process is computationally complex and therefore a subset of all data is normally considered for mining. In this paper, numerous methods for decomposition of data sets are discussed. Decomposition enhances the quality of knowledge extracted from large databases by simplification of the data mining task. The ideas presented are illustrated with examples and an industrial case study. In the case study reported in this paper, a data mining approach is applied to extract knowledge from a data set. The extracted knowledge is used for the prediction and prevention of manufacturing faults in wafers. | [
831,
998
] | Test |
2 | 2 | Exploration versus Exploitation in Topic Driven Crawlers Topic driven crawlers are increasingly seen as a way to address the scalability limitations of universal search engines, by distributing the crawling process across users, queries, or even client computers. The context available to a topic driven crawler allows for informed decisions about how to prioritize the links to be explored, given time and bandwidth constraints. We have developed a framework and a number of methods to evaluate the performance of topic driven crawler algorithms in a fair way, under limited memory resources. Quality metrics are derived from lexical features, link analysis, and a hybrid combination of the two. In this paper we focus on the issue of how greedy a crawler should be. Given noisy quality estimates of links in a frontier, we investigate what is an appropriate balance between a crawler's need to exploit this information to focus on the most promising links, and the need to explore links that appear suboptimal but might lead to more relevant pages. We show that exploration is essential to locate the most relevant pages under a number of quality measures, in spite of a penalty in the early stage of the crawl. | [
116,
608,
1021,
1512,
1547,
1838,
2372,
2459,
2503,
3170
] | Train |
3 | 3 | Software Engineering and Middleware: A Roadmap The construction of a large class of distributed systems can be simplified by leveraging middleware, which is layered between network operating systems and application components. Middleware resolves heterogeneity, and facilitates communication and coordination of distributed components. State of-the-practice middleware products enable software engineers to build systems that are distributed across a localarea network. State-of-the-art middleware research aims to push this boundary towards Internet-scale distribution, adaptive systems, middleware for dependable and wireless systems. The challenge for software engineering research is to devise notations, techniques, methods and tools for distributed system construction that systematically build and exploit the capabilities that middleware products deliver, now and in the future. | [
384
] | Train |
4 | 0 | Dynamic-Agents for Dynamic Service Provisioning We claim that a dynamic-agent infrastructure can provide a shift from static distributed computing to dynamic distributed computing, and we have developed such an infrastructure to realize such a shift. We shall show its impact on software engineering through a comparison with other distributed object-oriented systems such as CORBA and DCOM, and demonstrate its value in highly dynamic system integration and service provisioning. The infrastructure is Java-based, light-weight, and extensible. It differs from other agent platforms and client/server infrastructures in its support of dynamic behavior modification of agents. A dynamic-agent is not designed to have a fixed set of predefined functions but instead, to carry application-specific actions, which can be loaded and modified on the fly. This allows a dynamic-agent to adjust its capability for accommodating environment and requirement changes, and play different roles across multiple applications. The above features are supported b... | [
385
] | Validation |
5 | 0 | A Hybrid Mobile Robot Architecture with Integrated Planning and Control Research in the planning and control of mobile robots has received much attention in the past two decades. Two basic approaches have emerged from these research efforts: deliberative vs. reactive. These two approaches can be distinguished by their different usage of sensed data and global knowledge, speed of response, reasoning capability, and complexity of computation. Their strengths are complementary and their weaknesses can be mitigated by combining the two approaches in a hybrid architecture. This paper describes a method for goal-directed, collision-free navigation in unpredictable environments that employs a behavior-based hybrid architecture with asynchronously operating behavioral modules. It differs from existing hybrid architectures in two important ways: (1) the planning module produces a sequence of checkpoints instead of a conventional complete path, and (2) in addition to obstacle avoidance, the reactive module also performs target reaching under the control of a self-organizing neural network. The neural network is trained to perform fine, smooth motor control that moves the robot through the checkpoints. These two aspects facilitate a tight integration between high-level planning and low-level control, which permits real-time performance and easy path modification even when the robot is en route to the goal position. | [
2999
] | Test |
6 | 3 | Optimal External Memory Interval Management In this paper we present the external interval tree, an optimal external memory data structure for answering stabbing queries on a set of dynamically maintained intervals. The external interval tree can be used in an optimal solution to the dynamic interval management problem, which is a central problem for object-oriented and temporal databases and for constraint logic programming. Part of the structure uses a weight-balancing technique for efficient worst-case manipulation of balanced trees, which is of independent interest. The external interval tree, as well as our new balancing technique, have recently been used to develop several efficient external data structures. | [
228,
2488
] | Validation |
7 | 2 | Using PageRank to Characterize Web Structure Recent work on modeling the Web graph has dwelt on capturing the degree distributions observed on the Web. Pointing out that this represents a heavy reliance on "local" properties of the Web graph, we study the distribution of PageRank values (used in the Google search engine) on the Web. This distribution is of independent interest in optimizing search indices and storage. We show that PageRank values on the Web follow a power law. We then develop detailed models for the Web graph that explain this observation, and moreover remain faithful to previously studied degree distributions. We analyze these models, and compare the analyses to both snapshots from the Web and to graphs generated by simulations on the new models. To our knowledge this represents the first modeling of the Web that goes beyond fitting degree distributions on the Web. | [
2984
] | Test |
8 | 3 | XM2VTSDB: The Extended M2VTS Database In this paper we describe the acquisition and content of a large multi-modal database intended for training and testing of multi-modal verification systems. The XM2VTSDB database offers synchronised video and speech data as well as image sequences allowing multiple views of the face. It consists of digital video recordings taken of 295 hundred subjects at one month intervals taken over a period of five months. We also describe a protocol for evaluating verification algorithms on the database. The database has been made available to anyone on request to the University of Surrey through http://www.ee.surrey.ac.uk/Research/VSSP/xm2vtsdb. | [
2612
] | Validation |
9 | 0 | Design And Implementation Of The J-Seal2 Mobile Agent Kernel J-SEAL2 is a secure, portable, and efficient execution environment for mobile agents. The core of the system is a micro-kernel fulfilling the same functions as a traditional operating system kernel: protection, communication, domain termination, and resource control. This paper describes the key concepts of the J-SEAL2 micro-kernel and how they are implemented in pure Java. | [
560,
2337
] | Test |
10 | 3 | A Foundation for Conventional and Temporal Query Optimization Addressing Duplicates and Ordering AbstractÐMost real-world databases contain substantial amounts of time-referenced, or temporal, data. Recent advances in temporal query languages show that such database applications may benefit substantially from built-in temporal support in the DBMS. To achieve this, temporal query representation, optimization, and processing mechanisms must be provided. This paper presents a foundation for query optimization that integrates conventional and temporal query optimization and is suitable for both conventional DBMS architectures and ones where the temporal support is obtained via a layer on top of a conventional DBMS. This foundation captures duplicates and ordering for all queries, as well as coalescing for temporal queries, thus generalizing all existing approaches known to the authors. It includes a temporally extended relational algebra to which SQL and temporal SQL queries may be mapped, six types of algebraic equivalences, concrete query transformation rules that obey different equivalences, a procedure for determining which types of transformation rules are applicable for optimizing a query, and a query plan enumeration algorithm. The presented approach partitions the work required by the database implementor to develop a provably correct query optimizer into four stages: The database implementor has to 1) specify operations formally, 2) design and prove correct appropriate transformation rules that satisfy any of the six equivalence types, 3) augment the mechanism that determines when the different types of rules are applicable to ensure that the enumeration algorithm applies the rules correctly, and 4) ensure that the mapping generates a correct initial query plan. Index TermsÐTemporal databases, query optimization, transformation rules, temporal algebra, duplicate elimination, coalescing. 1 | [
460,
607,
1655,
2368
] | Train |
11 | 1 | Use of Satellite Image Referencing Algorithms to Characterize Asphaltic Concrete Mixtures A natural way to test the structural integrity of a pavement is to send signals with different frequencies through the pavement and compare the results with the signals passing through an ideal pavement. For this comparison, we must determine how, for the corresponding mixture, the elasticity E depends on the frequency f in the range from 0.1 to 10 5 Hz. It is very expensive to perform measurements in high frequency area (above 20 Hz). To avoid these measurements, we can use the fact that for most of these mixtures, when we change a temperature, the new dependence changes simply by scaling. Thus, instead of performing expensive measurements for different frequencies, we can measure the dependence of E on moderate frequencies f for different temperatures, and then combine the resulting curves into a single "master" curve. In this paper, we show how fuzzy techniques can help to automate this "combination". | [
3067
] | Test |
12 | 4 | RoboCup Rescue: Search and Rescue in Large-Scale Disasters as a Domain for Autonomous Agents Research Disaster rescue is one of the most serious social issue which involves very large numbers of hetergenious agents in the hostile environment. RoboCup-Rescue intends to promote research and development in this socially significant domain by creating a standard simulator and forum for researchers and practitioners. While the rescue domain intuitively appealing as large scale multi-agent domains, it has not yet given through analysis on its domain characteristics. In this paper, we present detailed analysis on the task domain and elucidate characteristics necessary for multi-agent systems for this domain. 1 Introduction In this paper, we propose RoboCup-Rescue, as a secondary domain for RoboCup activities [ Kitano, et al., 1997]. The aim of RoboCup-Rescue are (1) to ensure smooth transfer of technologies invented through RoboCup activity to a socially significant real world domain, (2) to establish a domain which complements features that are missing in soccer, and (3) to examine funderm... | [
770
] | Train |
13 | 4 | Virtual Information Towers - A Metaphor for Intuitive, Location-Aware Information Access in a Mobile Environment This paper introduces Virtual Information Towers (VITs) as a concept for presenting and accessing location-aware information with mobile clients. A VIT is a means of structuring location-aware information, which is assigned to a certain geographical position while having a certain area of visibility. A user equipped with a mobile, wearable computer has access to the VITs which are "visible" from his/her current location. The architecture and protocols of a system are described, which allows its users to create VITs and to access the information on them using Internet mechanisms. We have implemented a prototype of this system and a VIT client for a wearable computer and will present some aspects of this implementation. 1 Introduction Mobile information access is an important field of application for wearable computers. In a mobile environment much of the accessed information is location-dependent, i.e. the content of the information or the user's interest in the information depends on ... | [
554
] | Train |
14 | 1 | Off-line Learning of Coordination in Functionally Structured Agents for Distributed Data Processing When we design multi-agent systems for realistic, worth-oriented environments, coordination problems they present involve intricate and sophisticated interplay between the domain and the various system components. Achieving effective coordination in such systems is a difficult problem for a number of reasons like local views of problem-solving task and uncertainty about the outcomes of interacting non-local tasks. In this paper, we present a learning algorithm that endows agents with the capability to choose an appropriate coordination algorithm based on the present problem solving situation in the domain of distributed data processing. 1 Introduction Achieving effective coordination in a multi-agent system is a difficult problem for a number of reasons. The first is that an agent's control decisions, based only on its local view of problem-solving task structures, may lead to inappropriate decisions about which activity it should do next, what results it should transmit to other agen... | [
1107
] | Train |
15 | 3 | A Case for Parallelism in Data Warehousing and OLAP In recent years the database community has experienced a tremendous increase in the availability of new technologies to support efficient storage and retrieval of large volumes of data, namely data warehousing and On-Line Analytical Processing (OLAP) products. Efficient query processing is critical in such an environment, yet achieving quick response times with OLAP queries is still largely an open issue. In this paper we propose a solution approach to this problem by applying parallel processing techniques to a warehouse environment. We suggest an efficient partitioning strategy based on the relational representation of a data warehouse (i.e., star schema). Furthermore, we incorporate a particular indexing strategy, DataIndexes, to further improve query processing times and parallel resource utilization, and propose a preliminary parallel star-join strategy. 1 Introduction In recent years, there has been an explosive growth in the use of databases for decision support. This phenome... | [
539,
853,
2691
] | Validation |
16 | 2 | Error-Driven Pruning of Treebank Grammars for Base Noun Phrase Identification Finding simple, non-recursive, base noun phrases is an important subtask for many natural language processing applications. While previous empirical methods for base NP identification have been rather complex, this paper instead proposes a very simple algorithm that is tailored to the relative simplicity of the task. In particular, we present a corpus-based approach for finding base NPs by matching part-ofspeech tag sequences. The training phase of the algorithm is based on two successful techniques: first the base NP grammar is read from a "treebank" corpus; then the grammar is improved by selecting rules with high "benefit" scores. Using this simple algorithm with a naive heuristic for matching rules, we achieve surprising accuracy in an evaluation on the Penn Treebank Wall Street Journal. 1 Introduction Finding base noun phrases is a sensible first step for many natural language processing (NLP) tasks: Accurate identification of base noun phrases is arguably the most critical comp... | [
263,
2446,
2676
] | Test |
17 | 2 | A State-of-the-art Review on Multimodal Video Indexing Efficient and effective handling of video documents depends on the availability of indexes. Manual indexing is unfeasible for large video collections. Effective indexing requires a multimodal approach in which either the most appropriate modality is selected or the different modalities are used in collaborative fashion. In this paper we focus on the similarities and differences between the modalities, and survey several methods aiming at automating the time and resource consuming process of video indexing. Furthermore, we put forward a unifying and multimodal framework, which views a video document from the perspective of its author. This framework forms the guiding principle for identifying index types, for which automatic methods are found in literature. It furthermore forms the basis for categorizing these different methods. | [
1247,
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] | Train |
18 | 3 | Discovering Web Access Patterns and Trends by Applying OLAP and Data Mining Technology on Web Logs As a confluence of data mining and WWW technologies, it is now possible to perform data mining on web log records collected from the Internet web page access history. The behaviour of the web page readers is imprinted in the web server log files. Analyzing and exploring regularities in this behaviour can improve system performance, enhance the quality and delivery of Internet information services to the end user, and identify population of potential customers for electronic commerce. Thus, by observing people using collections of data, data mining can bring considerable contribution to digital library designers. In a joint effort between the TeleLearning-NCE project on Virtual University and NCE-IRIS project on data mining, we have been developing the knowledge discovery tool, WebLogMiner, for mining web server log files. This paper presents the design of the WebLogMiner, reports the current progress, and outlines the future work in this direction. | [
1004,
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3138
] | Train |
19 | 3 | Managing the Operator Ordering Problem in Parallel Databases This paper focuses on parallel query optimization. We consider the operator problem and introduce a new class of execution strategies called Linear-Oriented Bushy Trees (LBT). Compared to the related approach of the General Bushy Trees (GBT) a significant complexity reduction of the operator ordering problem can be derived theoretically and demonstrated experimentally (e.g. compared with GBTs, LBTs authorize optimization time improvement that can reach up-to 49%) without loosing quality. Finally we demonstrate that existing commercial parallel query optimizers need little extension modifications in order to handle LBTs. Key words: Parallel databases, parallel query optimization, linear-oriented bushy trees, extending existing optimizers. 1 Introduction Modern database applications, such as data mining and decision support pose several new challenges to query optimization and processing [1]. One of the main issues concerns the processing of complex queries (e.g. recent Teradata rela... | [
1879
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20 | 2 | SpeechBot: a Speech Recognition based Audio Indexing System for the Web We have developed an audio search engine incorporating speech recognition technology. This allows indexing of spoken documents from the World Wide Web when no transcription is available. This site indexes several talk and news radio shows covering a wide range of topics and speaking styles from a selection of public Web sites with multimedia archives. Our Web site is similar in spirit to normal Web search sites; it contains an index, not the actual multimedia content. The audio from these shows suffers in acoustic quality due to bandwidth limitations, coding, compression, and poor acoustic conditions. The shows are typically sampled at 8 kHz and transmitted, RealAudio compressed, at 6.5 kbps. Our word-error rate results using appropriately trained acoustic models show remarkable resilience to the high compression, though many factors combine to increase the average word-error rates over standard broadcast news benchmarks. We show that, even if the transcription is inaccurate, we can st... | [
1524,
1815,
1895,
2907
] | Test |
21 | 4 | Context Awareness by Analysing Accelerometer Data In this paper we describe continuing work being carried out as part of the Bristol Wearable Computing Initiative. We are researching processing techniques for data from accelerometers which enable the wearable computer to determine the user's activity. We have experimented with, and review, techniques already employed by others; and then propose new methods for analysing the data delivered by these devices. We try to minimise the number of devices needed, and use a single X-Y accelerometer device. Using our techniques we have adapted our GPS based Tourist Guide wearable Computer application to include a multimedia presentation which gives the user information using different media depending on the user's activity as well as location. 1 Introduction and Background This is a condensed version of a technical report. [1] Our interests in wearable computing are centred around determining the context of the user and developing applications which make use of this information. We are expl... | [
283,
2617,
2996
] | Validation |
22 | 1 | Actor-Critic Algorithms We propose and analyze a class of actor-critic algorithms for simulation-based optimization of a Markov decision process over a parameterized family of randomized stationary policies. These are two-time-scale algorithms in which the critic uses TD learning with a linear approximation architecture and the actor is updated in an approximate gradient direction based on information provided by the critic. We show that the features for the critic should span a subspace prescribed by the choice of parameterization of the actor. We conclude by discussing convergence properties and some open problems. 1 Introduction The vast majority of Reinforcement Learning (RL) [9] and Neuro-Dynamic Programming (NDP) [1] methods fall into one of the following two categories: (a) Actor-only methods work with a parameterized family of policies. The gradient of the performance, with respect to the actor parameters, is directly estimated by simulation, and the parameters are updated in a direction o... | [
215,
1133,
1880
] | Validation |
23 | 4 | Interfaces and Tools for the Library of Congress National Digital Library Program This paper describes a collaborative effort to explore user needs in a digital library, develop interface prototypes for a digital library, and suggest and prototype tools for digital librarians and users at the Library of Congress (LC). Interfaces were guided by an assessment of user needs and aimed to maximize interaction with primary resources and support both browsing and analytical search strategies. Tools to aid users and librarians in overviewing collections, previewing objects, and gathering results were created and serve as the beginnings of a digital librarian toolkit. The design process and results are described and suggestions for future work are offered. Digital Libraries (DL) offer new challenges to an emerging breed of digital librarians who must combine the principles and practices of information management with rapidly evolving technological developments to create new information products and services. This paper describes a collaborative effort to explore user needs ... | [
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24 | 3 | Computing and Comparing Semantics of Programs in Four-valued Logics The different semantics that can be assigned to a logic program correspond to different assumptions made concerning the atoms whose logical values cannot be inferred from the rules. Thus, the well founded semantics corresponds to the assumption that every such atom is false, while the Kripke-Kleene semantics corresponds to the assumption that every such atom is unknown. In this paper, we propose to unify and extend this assumption-based approach by introducing parameterized semantics for logic programs. The parameter holds the value that one assumes for all atoms whose logical values cannot be inferred from the rules. We work within Belnap's four-valued logic, and we consider the class of logic programs defined by Fitting. Following Fitting's approach, we define a simple operator that allows us to compute the parameterized semantics, and to compare and combine semantics obtained for different values of the parameter. The semantics proposed by Fitting corresponds to the value false. We also show that our approach captures and extends the usual semantics of conventional logic programs thereby unifying their computation. | [
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25 | 1 | An Object-Oriented Case-Based Learning System This thesis first gives an overview of the subfield of classification in the area of machine learning. The numerous variants of Case-Based Learning algorithms are compared according to what kind of data is processed, how knowledge and hypotheses are represented, and what kind of reasoning or learning is performed. The strengths and weaknesses of these learning methods are compared to each other and to other groups of learning methods. A modular object-oriented LISP environment, VIE-CBR2 is introduced, that implements a number of algorithms for Case-Based Learning. This system allows to easily combine preprogrammed learning algorithms. and provides a framework for simple integration of new learning algorithms and other components that make use of the basic system. | [
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26 | 4 | A Pattern Approach to Interaction Design To create successful interactive systems, user interface designers need to cooperate with developers and application domain experts in an interdisciplinary team. These groups, however, usually miss a common terminology to exchange ideas, opinions, and values. This paper presents an approach that uses pattern languages to capture this knowledge in software development, HCI, and the application domain. A formal, domain-independent definition of design patterns allows for computer support without sacrificing readability, and pattern use is integrated into the usability engineering lifecycle. As an example, experience from building an award-winning interactive music exhibit was turned into a pattern language, which was then used to inform follow-up projects and support HCI education. | [
517
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27 | 0 | Communication Primitives for Ubiquitous Systems or RPC Considered Harmful RPC is widely used to access and modify remote state. Its procedural call semantics are argued as an efficient unifying paradigm for both local and remote access. Our experience with ubiquitous device control systems has shown otherwise. RPC semantics of a synchronous, blocking invocation on a statically typed interface are overly restrictive, inflexible, and fail to provide an efficient unifying abstraction for accessing and modifying state in ubiquitous systems. This position paper considers other alternatives and proposes the use of comvets (conditional, mobility aware events) as the unifying generic communication paradigm for such systems. Keywords: RPC, RMI, Events, Comvets, CORBA, Jini 1 Introduction Ubiquitous environments or active spaces are the next generation of device control networks. A user interacts with an active space by using novel interfaces like speech and gesture input [1] to control her environment, and the system interacts with the user using audio/video outpu... | [
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28 | 0 | Multi-User and Security Support for Multi-Agent Systems This paper discusses the requirements an agent system needs to be secure. In particular, the paper introduces a classification of modern distributed systems, and examines the delegation concept from a security point of view. After discussing the peculiar security and delegation issues present in distributed object systems, mobile agent systems and in multi agent systems, a case study is presented, describing the multi-user and security support that is being built into the JADE platform. | [
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29 | 3 | Benchmarking XML Management Systems: The XOO7 Way The effectiveness of existing XML query languages has been studied by many who focused on the comparison of linguistic features, implicitly reflecting the fact that most XML tools exist only on paper. In this paper, with a focus on efficiency and concreteness, we propose a pragmatic first step toward the systematic benchmarking of XML query processing platforms. We begin by identifying the necessary functionalities an XML data management system should support. We review existing approaches for managing XML data and the query processing capabilities of these approaches. We then compare three XML query benchmarks XMach-1, XMark and XOO7 and discuss the applicability, strengths and limitations of these benchmarks. We highlight the bias of these benchmarks towards the data centric view of XML and motivate our selection of XOO7 to extend with document centric queries. We complete XOO7 to capture the information retrieval capabilities of XML management systems. Finally we summarize our contributions and discuss future directions. | [
379,
781,
1318,
2910,
2962
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30 | 3 | dQUOB: Managing Large Data Flows Using Dynamic Embedded Queries The dQUOB system satisfies client need for specific information from high-volume data streams. The data streams we speak of are the flow of data existing during large-scale visualizations, video streaming to large numbers of distributed users, and high volume business transactions. We introduces the notion of conceptualizing a data stream as a set of relational database tables so that a scientist can request information with an SQL-like query. Transformation or computation that often needs to be performed on the data en-route can be conceptualized ascomputation performed onconsecutive views of the data, with computation associated with each view. The dQUOB system moves the query code into the data stream as a quoblet; as compiled code. The relational database data model has the significant advantage of presenting opportunities for efficient reoptimizations of queries and sets of queries. Using examples from global atmospheric modeling, we illustrate the usefulness of the dQUOB system. We carry the examples through the experiments to establish the viability of the approach for high performance computing with a baseline benchmark. We define a cost-metric of end-to-end latency that can be used to determine realistic cases where optimization should be applied. Finally, we show that end-to-end latency can be controlled through a probability assigned to a query that a query will evaluate to true. | [
83,
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] | Train |
31 | 4 | A Multi-version Approach to Conflict Resolution in Distributed Groupware Systems Groupware systems are a special class of distributed computing systems which support human-computer-human interaction. Real-time collaborative graphics editors allow a group of users to view and edit the same graphics document at the same time from geographically dispersed sites connected by communication networks. Resolving conflict access to shared objects is one of the core issues in the design of this type of systems. This paper proposes a novel distributed multi-version approach to conflict resolution. This approach aims to preserve the work concurrently produced by multiple users in the face of conflicts, and to minimize the number of object versions for accommodating combined effects of conflicting and compatible operations. Major technical contributions of this work include a formal specification of a unique combined effect for any group of conflicting and compatible operations, a distributed algorithm for incremental creation of multiple object versions, and a consistent objec... | [
307
] | Train |
32 | 2 | Development and Evaluation of Clustering Techniques for Finding People Typically in a large organisation much expertise and knowledge is held informally within employees' own memories. When employees leave an organisation many documented links that go through that person are broken and no mechanism is usually available to overcome these broken links. This matchmaking problem is related to the problem of finding potential work partners in a large and distributed organisation. This paper reports a comparative investigation into using standard information retrieval techniques to group employees together based on their web pages. This information can, hopefully, be subsequently used to redirect broken links to people who worked closely with a departed employee or used to highlight people, say in different departments, who work on similar topics. The paper reports the design and positive results of an experiment conducted at Ris National Laboratory comparing four different IR searching and clustering approaches using real users' we... | [
544
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33 | 3 | Use Case Maps as a Feature Description Notation . We propose Use Case Maps (UCMs) as a notation for describing features. UCMs capture functional requirements in terms of causal scenarios bound to underlying abstract components. This particular view proved very useful in the description of a wide range of reactive and telecommunications systems. This paper presents some of the most interesting constructs and benefits of the notation in relation to a question on a User Requirements Notation recently approved by ITU-T Study Group 10, which will lead to a new Recommendation by 2003. Tool support, current research on UCMs, and related notations are also discussed. 1 Introduction The modeling of reactive systems requires an early emphasis on behavioral aspects such as interactions between the system and the external world (including the users), on the cause-to-e#ect relationships among these interactions, and on intermediate activities performed by the system. Scenarios are particularly good at representing such aspects so that various ... | [
396
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34 | 4 | Computer Response to User Frustration Use of computer technology often has unpleasant side effects, some of which are strong, negative emotional states that arise in humans during interaction with computers. Frustration, confusion, anger, anxiety and similar emotional states can affect not only the interaction itself, but also productivity, learning, social relationships, and overall well-being. This thesis presents the idea of designing human-computer interaction systems to actively support human users in their ability to regulate, manage, and recover from their own negative emotional states, particularly frustration. This document describes traditional theoretical strategies for emotion regulation, the design of a human-computer interaction agent built by the author to actively help relieve frustration, and an evaluation that shows the effectiveness of the agent. A study designed to test this agent was conducted: A system was built that elicits frustration in human subjects. The interaction agent then initiated several social, emotional-content feedback strategies with some of the subjects, in an effort to help relieve their emotional state. These strategies were designed to provide many of the same cues that skilled, human listeners employ when helping relieve strong, negative emotions in others. Two control groups were exposed to the same frustrating stimuli, one of which was given no emotional support at all; the other enabled subjects to report problems and "vent" at the computer. Subsequent behavior was then observed, and self-report data was collected. Behavioral results showed the agent was significantly more effective than the two controls in helping relieve frustration levels in subjects. These results demonstrate that strategic, social, emotional-content interaction with a computer by users who ... | [
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35 | 2 | Hermes - A Notification Service for Digital Libraries The high publication rate of scholarly material makes searching and browsing an inconvenient way to keep oneself up-todate. Instead of being the active part in information access, researchers want to be notified whenever a new paper in one's research area is published. | [
868,
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] | Train |
36 | 2 | Open video: A framework for a test collection This paper provides a framework for such a test collection and describes the Open Video Project that has begun to develop a test collection based on this framework. The proposed test collection is meant to be used to study a wide range of problems, such as tests of algorithms for creating surrogates for video content or interfaces that display result sets from queries. An important challenge in developing such a collection is storing and distributing video objects. This paper is meant to layout video management issues that may influence distributed storage solutions. More specifically, this paper describes the first phase for creating the test collection, sets guidelines for building the collection, and serves as a basis for discussion to inform subsequent phases and invite research community involvement. 2000 Academic Press 1. Introduction It is inevitable that the technical limitations that impede widespread usage of video libraries will dimi | [
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37 | 0 | Implementing Teams of Agents Playing Simulated Robot Soccer . This article is intended to present an overview of the issues related to implementing teams of cooperating agents playing simulated robot soccer. First we introduce the concept of robot soccer and the simulated environment. Then we discuss why the (simulated) robot soccer is an interesting application area from the point of view of robotics and articial intelligence. The main part of the paper contains a discussion of agent architectures, both from theoretical and practical point of view. Later we discuss how to combine individual agents into teams having common strategies and goals. We also discuss learning, both on individual and team levels. 1 Introduction Robot soccer is a growing area of interest for the robotics and articial intelligence communities. There are many reasons for that. The main one is the complexity of the domain together with a set of well-dened rules governing the behaviour of the agents in this domain. The domain is suited for experiments both in ... | [
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38 | 1 | Formal Concepts of Learning Systems Validation in Use In the problem area of evaluating complex software systems, there are two distinguished areas of research, development, and application identified by the two buzzwords validation and verification, respectively. From the perspective adopted by the authors (cf. (O'Keefe & O'Leary 1993), e.g.), verification is usually more formally based and, thus, can be supported by formal reasoning tools like theorem provers, for instance. The scope of verification approaches is limited by the difficulty of finding a sufficiently complete formalization to built upon. In paramount realistic problem domains, validation seems to be more appropriate, although it is less stringent in character and, therefore, validation results are often less definite. The aim of this paper is to exemplify a validation approach based on a clear and thoroughly formal theory. In this way, validation and verification should be brought closer to each other, for the benefit of a concerted action towards depend... | [
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39 | 2 | Web Usage Mining - Languages and Algorithms We propose two new XML applications, XGMML and LOGML. XGMML is a graph description language and LOGML is a web-log report description language. We generate a web graph in XGMML format for a web site using the web robot of the WWWPal system (developed for web visualization and organization). We generate web-log reports in LOGML format for a web site from web log files and the web graph. In this paper, we further illustrate the usefulness of these two XML applications with a web data mining example. Moreover, we show the simplicity with which this mining algorithm can be specified and implemented efficiently using our two XML applications. We provide sample results, namely frequent patterns of users in a web site, with our web data mining algorithm. | [
255
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40 | 3 | Minimizing View Sets without Losing Query-Answering Power The problem of answering queries using views has been studied extensively, due to its relevance in a wide variety of data-management applications. In these applications, we often need to select a subset of views to maintain, due to limited resources. In this paper, we show that traditional query containment is not a good basis for deciding whether or not a view should be selected. Instead, we should minimize the view set without losing query-answering power. To formalize this notion, we rst introduce the concept of "p-containment." That is, a view set V is p-contained in another view set W, if W can answer all the queries that can be answered by V. We show that p-containment and the traditional query containment are not related; i.e., one does not imply the other. We then discuss how to minimize a view set while retaining its query-answering power. We develop the idea further by considering p-containment of two view sets with respect to a given set of queries, and consider their relationship in terms of maximally-contained rewritings of queries using the views. | [
689,
806,
2080
] | Validation |
41 | 4 | Towards Group Communication for Mobile Participants (Extended Abstract) Group communication will undoubtedly be a useful paradigm for many applications of wireless networking in which reliability and timeliness are requirements. Moreover, location awareness is clearly central to mobile applications such as traffic management and smart spaces. In this paper, we introduce our definition of proximity groups in which group membership depends on location and then discuss some requirements for a group membership management service suitable for proximity groups. We describe a novel approach to efficient coverage estimation, giving applications feedback on the proportion of the area of interest covered by a proximity group, and also discuss our approach to partition anticipation. | [
2248,
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] | Train |
42 | 2 | Estimating Resemblance of MIDI Documents Abstract. Search engines often employ techniques for determining syntactic similarity of Web pages. Such a tool allows them to avoid returning multiple copies of essentially the same page when a user makes a query. Here we describe our experience extending these techniques to MIDI music files. The music domain requires modification to cope with problems introduced in the musical setting, such as polyphony. Our experience suggests that when used properly these techniques prove useful for determining duplicates and clustering databases in the musical setting as well. 1 | [
2135
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43 | 1 | Distinctive Features Should Be Learned Most existing machine vision systems perform recognition based on a xed set of hand-crafted features, geometric models, or eigen-subspace decomposition. Drawing from psychology, neuroscience and intuition, we show that certain aspects of human performance in visual discrimination cannot be explained by any of these techniques. We argue that many practical recognition tasks for articial vision systems operating under uncontrolled conditions critically depend on incremental learning. Loosely motivated by visuocortical processing, we present feature representations and learning methods that perform biologically plausible functions. The paper concludes with experimental results generated by our method. 1 Introduction How exible are the representations for visual recognition, encoded by the neurons of the human visual cortex? Are they predetermined by a xed developmental schedule, or does their development depend on their stimulation? Does their development cease at some poin... | [
1675
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44 | 3 | Interaction between Path and Type Constraints XML [7], which is emerging as an important standard for data exchange on the World-Wide Web, highlights the importance of semistructured data. Although the XML standard itself does not require any schema or type system, a number of proposals [6, 17, 19] have been developed that roughly correspond to data definition languages. These allow one to constrain the structure of XML data by imposing a schema on it. These and other proposals also advocate the need for integrity constraints, another form of constraints that should, for example, be capable of expressing inclusion constraints and inverse relationships. The latter have recently been studied as path constraints in the context of semistructured data [4, 9]. It is likely that future XML proposals will involve both forms of constraints, and it is therefore appropriate to understand the interaction between them. This paper investigates that interaction. In particular it studies constraint implication problems, which are important both i... | [
1318,
1600
] | Test |
45 | 4 | Aspects of Network Edge Intelligence Is it the case that the migration of intelligence from the core of networks to the periphery is simply a function of the IP protocols? Or are there more fundamental forces at work? This report addresses this issue from the perspective of core network protocols, mobile networking and the emerging embedded Internet. It identifies the forces at work, and concludes that the long term trends are driven by more than simply the end-to-end argument. If the logical progression of this trend is that intelligence will migrate to the embedded Internet, then a new type of peripheral intelligence may form the basis for further progress. The report concludes by identifying the challenges for the embedded Internet in constructed environments. Keywords: IP networking, intelligence, architecture, smart spaces Aspects of Network Edge Intelligence I. | [
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46 | 1 | Robustness of Case-Initialized Genetic Algorithms We investigate the robustness of Case Initialized Genetic AlgoRithm (CIGAR) systems with respect to problem indexing. When confronted with a series of similar problems CIGAR stores potential solutions in a case-base or an associative memory and retrieves and uses these solutions to help improve a genetic algorithm 's performance over time. Defining similarity among the problems, or indexing, is key to performance improvement. We study four indexing schemes on a class of simple problems and provide empirical evidence of CIGAR's robustness to imperfect indexing. | [
2010
] | Train |
47 | 1 | Learning to Tag for Information Extraction from Text . LearningPINOCCHIO is an algorithm for adaptive information extraction. It learns template filling rules that insert SGML tags into texts. LearningPINOCCHIO is based on a covering algorithm that learns rules by bottom-up generalization of instances in a tagged corpus. It has been tested on three scenarios in informal domains in two languages (Italian and English). Experiments report excellent results with respect to the current state of the art. 1 Introduction By general agreement the main barriers to wide use and commercialization of IE are the difficulties in adapting systems to new applications and domains. In the last years there has been increasing interest in applying machine learning to Information Extraction from text [13, 3, 9, 1, 11]. In particular there is an increasing interest in the application of adaptive IE to Web pages [12, 10] and to informal domains (rental ads, email messages, etc.) [15, 8, 2] for building fully automated systems. This is due from one side to the... | [
710,
1623,
2032,
2068,
3098
] | Train |
48 | 4 | A Natural Interface to a Virtual Environment through Computer Vision-estimated Pointing Gestures . This paper describes the development of a natural interface to a virtual environment. The interface is through a natural pointing gesture and replaces pointing devices which are normally used to interact with virtual environments. The pointing gesture is estimated in 3D using kinematic knowledge of the arm during pointing and monocular computer vision. The latter is used to extract the 2D position of the user's hand and map it into 3D. Off-line tests of the system show promising results with an average errors of 76mm when pointing at a screen 2m away. The implementation of a real time system is currently in progress and is expected to run with 25Hz. 1 | [
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49 | 0 | Rapid Concurrent Software Engineering in Competitive Situations This article is an experience report on the evolutionary development process of AT Humboldt, a multi agent system which has become World Champion 1997 and Vice World Champion 1998 of RoboCup simulator league. It details why the artifical soccer initiative RoboCup is a tempting domain for rapid concurrent software engineering. Both the development processes in 1997 and 1998 are described, compared and evaluated. Lessons learned for development projects in distributed control conclude this report. 1 Introduction In this article the project managers describe the evolutionary development process of the software project AT (AgentTeam) Humboldt, which has become World Champion 1997 and Vice World Champion 1998 in the simulator league of the artifical soccer contest RoboCup ([10]). The RoboCup initiative recently gets more and more popular among scientists in robotics, distributed systems and distributed artificial intelligence because of its strong competitive character and tight resource b... | [
321,
346,
867,
2364
] | Test |
50 | 0 | Economic Markets as a Means of Open Mobile-Agent Systems Mobile-agent systems have gained popularity in use because they ease the application design process by giving software engineers greater flexibility. Although the value of any network is dependent on both the number of users and the number of sites participating in the network, there is little motivation for systems to donate resources to arbitrary agents. We propose to remedy the problem by imposing an economic market on mobile-agent systems where agents purchase resources from host sites and sell services to users and other agents. Host sites accumulate revenues, which are distributed to users to be used to launch more agents. We argue for the use of markets to regulate mobile-agent systems and discuss open issues in implementing market-based mobile-agent systems. 1 Introduction One of the more recent items in a network programmer's tool box is code mobility. The technique is becoming more common in applications programming, network management [BPW98], video conferencing [BPR98], so... | [
911,
1905,
2709
] | Test |
51 | 0 | Graphical Models for Recognizing Human Interactions We describe a real-time computer vision and machine learning system for modeling and recognizing human actions and interactions. Two different domains are explored: recognition of two-handed motions in the martial art 'Tai Chi', and multiple-person interactions in a visual surveillance task. Our system combines top-down with bottom-up information using a feedback loop, and is formulated with a Bayesian framework. Two different graphical models (HMMs and Coupled HMMs) are used for modeling both individual actions and multiple-agent interactions, and CHMMs are shown to work more efficiently and accurately for a given amount of training. Finally, to overcome the limited amounts of training data, we demonstrate that `synthetic agents' (Alife-style agents) can be used to develop flexible prior models of the person-to-person interactions. 1 INTRODUCTION We describe a real-time computer vision and machine learning system for modeling and recognizing human behaviors in two different scenari... | [
690,
919,
2107
] | Train |
52 | 2 | Adaptive Load Sharing for Network Processors A novel scheme for processing packets in a router is presented, which provides for load sharing among multiple network processors distributed within the router. It is complemented by a feedback control mechanism designed to prevent processor overload. Incoming traffic is scheduled to multiple processors based on a deterministic mapping. The mapping formula is derived from the robust hash routing (also known as the highest random weight - HRW) scheme, introduced in K.W. Ross, IEEE Network, 11(6), 1997, and D.G. Thaler et al., IEEE Trans. Networking, 6(1), 1998. No state information on individual flow mapping needs to be stored, but for each packet, a mapping function is computed over an identifier vector, a predefined set of fields in the packet. An adaptive extension to the HRW scheme is provided in order to cope with biased traffic patterns. We prove that our adaptation possesses the minimal disruption property with respect to the mapping and exploit that property in order to minimize the probability of flow reordering. Simulation results indicate that the scheme achieves significant improvements in processor utilization. A higher number of router interfaces can thus be supported with the same amount of processing power. I. | [
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53 | 1 | Approximate Nearest Neighbor Queries Revisited This paper proposes new methods to answer approximate nearest neighbor queries on a set of n points in d-dimensional Euclidean space. For any fixed constant d, a data structure with O(" (1\Gammad)=2 n log n) preprocessing time and O(" (1\Gammad)=2 log n) query time achieves approximation factor 1 + " for any given 0 ! " ! 1; a variant reduces the "-dependence by a factor of " \Gamma1=2 . For any arbitrary d, a data structure with O(d 2 n log n) preprocessing time and O(d 2 log n) query time achieves approximation factor O(d 3=2 ). Applications to various proximity problems are discussed. 1 Introduction Let P be a set of n point sites in d-dimensional space IR d . In the well-known post office problem, we want to preprocess P into a data structure so that a site closest to a given query point q (called the nearest neighbor of q) can be found efficiently. Distances are measured under the Euclidean metric. The post office problem has many applications within computational... | [
325,
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] | Validation |
54 | 3 | A Geometric Framework for Specifying Spatiotemporal Objects We present a framework for specifying spatiotemporal objects using spatial and temporal objects, and a geometric transformation. We define a number of classes of spatiotemporal objects and study their closure properties. 1 Introduction Many natural or man-made phenomena have both a spatial and a temporal extent. Consider for example, a forest fire or property histories in a city. To store information about such phenomena in a database one needs appropriate data modeling constructs. We claim that a new concept, spatiotemporal object, is necessary. In this paper, we introduce a very general framework for specifying spatiotemporal objects. To define a spatiotemporal object we need a spatial object, a temporal object, and a continuous geometric transformation (specified using a parametric representation) that determines the image of the spatial object at different time instants belonging to the temporal object. In this framework, a number of classes of spatiotemporal objects arise quite ... | [
72,
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55 | 3 | SI-Designer: a tool for intelligent integration of information SI-Designer (Source Integrator Designer) is a designer support tool for semi � automatic integration of heterogeneous sources schemata (relational, object and semi � structured sources); it has been implemented within the MOMIS project and it carries out integration following a semantic approach which uses intelligent Description Logics-based techniques, clustering techniques and an extended ODMG-ODL language, �������� � , to represent schemata, extracted, integrated information. Starting from the sources ’ �������� � descriptions (local schemata) SI-Designer supports the designer in the creation of an integrated view of all the sources (global schema) which is expressed in the same �������� � language. We propose SI-Designer as a tool to build virtual catalogs in the E-Commerce environment. 1. | [
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56 | 2 | Information-Theoretic Learning This chapter seeks to extend the ubiquitous mean-square error criterion (MSE) to cost functions that include more information about the training data. Since the learning process ultimately should transfer the information carried in the data samples onto the system's parameters, a natural goal is to find cost functions that directly manipulate information. Hence the name informationtheoretic learning (ITL). In order to be useful, ITL should be independent of the learning machine architecture, and require solely the availability of the data, i.e. it should not require a priori assumptions about the data distributions. The chapter presents our current efforts to develop ITL criteria based on the integration of nonparametric density estimators with Renyi's quadratic entropy definition. As a motivation we start with an application of the MSE to manipulate information using the nonlinear characteristics of the learning machine. This section illustrates the issues faced when we attempt to use... | [
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57 | 3 | First-Order Polynomial Based Theorem Proving Introduction The Boolean ring or first-order polynomial based theorem proving began with the work of Hsiang (1982, 1985). Hsiang extended the idea of using Boolean polynomials to represent propositional formulae to the case of first-order predicate calculus. Based on the completion procedure of Knuth and Bendix (1970), the N-strategy was proposed. Later on, by imitating the framework of Buchberger 's algorithm to compute the Grobner bases of polynomial ideals (Buchberger 1985), Kapur and Narendran (1985) developed another approach which is also referred to as the Grobner basis method. One obvious advantage of using Boolean polynomials is that every propositional formula has a unique representation, and sometimes it is easy to be generalized to some non-classical logic systems (Chazarain et al. 1991; Wu and Tan 1994). Stimulated by them, some approaches and results have been reported (Bachmair and Dershowitz 1987; Dietrich 1986; Kapur and Zhang 1989; Wu and Liu 1998; Zhang 198 | [] | Train |
58 | 2 | Learning Algorithms for Keyphrase Extraction Many academic journals ask their authors to provide a list of about five to fifteen keywords, to appear on the first page of each article. Since these key words are often phrases of two or more words, we prefer to call them keyphrases. There is a wide variety of tasks for which keyphrases are useful, as we discuss in this paper. We approach the problem of automatically extracting keyphrases from text as a supervised learning task. We treat a document as a set of phrases, which the learning algorithm must learn to classify as positive or negative examples of keyphrases. Our first set of experiments applies the C4.5 decision tree induction algorithm to this learning task. We evaluate the performance of nine different configurations of C4.5. The second set of experiments applies the GenEx algorithm to the task. We developed the GenEx algorithm specifically for automatically extracting keyphrases from text. The experimental results support the claim that a custom-designed algorithm (GenEx)... | [
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59 | 4 | Nomadic Radio: Scaleable and Contextual Notification for Wearable Audio Messaging Mobile workers need seamless access to communication and information services on portable devices. However current solutions overwhelm users with intrusive and ambiguous notifications. In this paper, we describe scaleable auditory techniques and a contextual notification model for providing timely information, while minimizing interruptions. User's actions influence local adaptation in the model. These techniques are demonstrated in Nomadic Radio, an audio-only wearable computing platform. | [
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60 | 2 | Object-Based Multimedia Content Description Schemes and Applications for MPEG-7 In this paper, we describe description schemes (DSs) for image, video, multimedia, home media, and archive content proposed to the MPEG-7 standard. MPEG-7 aims to create a multimedia content description standard in order to facilitate various multimedia searching and filtering applications. During the design process, special care was taken to provide simple but powerful structures that represent generic multimedia data. We use the eXtensible Markup Language (XML) to illustrate and exemplify the proposed DSs because of its interoperability and flexibility advantages. The main components of the image, video, and multimedia description schemes are object, feature classification, object hierarchy, entity-relation graph, code downloading, multi-abstraction levels, and modality transcoding. The home media description instantiates the former DSs proposing the 6-W semantic features for objects, and 1-P physical and 6-W semantic object hierarchies. The archive description scheme aims to describ... | [
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61 | 0 | Error-Tolerant Agents . The use of agents in today's Internet world is expanding rapidly. Yet, agent developers | [
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62 | 3 | Approximate Query Translation across Heterogeneous Information Sources (Extended Version) In this paper we present a mechanism for approximately translating Boolean query constraints across heterogeneous information sources. Achieving the best translation is challenging because sources support different constraints for formulating queries, and often these constraints cannot be precisely translated. For instance, a query [score ? 8] might be "perfectly" translated as [rating ? 0.8] at some site, but can only be approximated as [grade = A] at another. Unlike other work, our general framework adopts a customizable "closeness" metric for the translation that combines both precision and recall. Our results show that for query translation we need to handle interdependencies among both query conjuncts as well as disjuncts. As the basis, we identify the essential requirements of a rule system for users to encode the mappings for atomic semantic units. Our algorithm then translates complex queries by rewriting them in terms of the semantic units. We show that, un... | [
282,
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63 | 1 | DirectSVM: A Fast And Simple Support Vector Machine Perceptron . We propose a simple implementation of the Support Vector Machine (SVM) for pattern recognition, that is not based on solving a complex quadratic optimization problem. Instead we propose a simple, iterative algorithm that is based on a few simple heuristics. The proposed algorithm nds high-quality solutions in a fast and intuitively-simple way. In experiments on the COIL database, on the extended COIL database and on the Sonar database of the UCI Irvine repository, DirectSVM is able to nd solutions that are similar to these found by the original SVM. However DirectSVM is able to nd these solutions substantially faster, while requiring less computational resources than the original SVM. INTRODUCTION Support Vector Machines (SVMs) belong to the best-performing learning algorithms available. They have produced remarkable performance in a number of dicult learning tasks without requiring prior knowledge. We mention amongst others the following examples in pattern recognition: handwr... | [
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64 | 1 | Bias, Variance, and Error Correcting Output Codes for Local Learners : This paper focuses on a bias variance decomposition analysis of a local learning algorithm, the nearest neighbor classifier, that has been extended with error correcting output codes. This extended algorithm often considerably reduces the 0-1 (i.e., classification) error in comparison with nearest neighbor (Ricci & Aha, 1997). The analysis presented here reveals that this performance improvement is obtained by drastically reducing bias at the cost of increasing variance. We also show that, even in classification problems with few classes (m5), extending the codeword length beyond the limit that assures column separation yields an error reduction. This error reduction is not only in the variance, which is due to the voting mechanism used for error-correcting output codes, but also in the bias. Keywords: Case-based learning, classification, error-correcting output codes, bias and variance Email: ricci@irst.itc.it, aha@aic.nrl.navy.mil Phone: ++39 461 314334 FAX: ++39 461 302040 Bi... | [
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65 | 3 | Schema Evolution in Heterogeneous Database Architectures, A Schema Transformation Approach In previous work we have a developed general framework to support schema transformation and integration in heterogeneous database architectures. The framework consists of a hypergraph-based common data model and a set of primitive schema transformations defined for this model. Higher-level common data models and primitive schema transformations for them can be defined in terms of this lower-level model. A key feature of the framework is that both primitive and composite schema transformations are automatically reversible. We have shown in earlier work how this allows automatic query translation from a global schema to a set of source schemas. In this paper we show how our framework also readily supports evolution of source schemas, allowing the global schema and the query translation pathways to be easily repaired, as opposed to having to be regenerated, after changes to source schemas. 1 | [
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66 | 4 | Dynamic Connection of Wearable Computers to Companion Devices Using Near-Field Radio Hewlett-Packard Laboratories, Bristol and the University of Bristol Department of Computer Science are engaged in an initiative to explore the design, technology and use of wearable computers. We describe a way of connecting a wearable computer to companion devices such as displays or cameras using near-field radio technology. The shortrange nature of near-field radio allows relatively high data rates (300 kbps -- 1Mbit), low power consumption and the interpretation of gestures as configuration requests. Keywords: Near-field radio, dynamic connectivity. INTRODUCTION We are particularly interested in communication technologies that exhibit low-power, short range (up to 1 foot) and modest data rates (300 kbps -- 1 Mbs). The action of picking up a companion device (such as a display) establishes the communication link due to the very short range. An important aspect of a suitable communication technology is that the user is not required to touch an electrode and therefore handling of ... | [
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67 | 3 | SIC: Satisfiability Checking for Integrity Constraints SIC is an interactive prototype to assist in the design of finitely satisfiable integrity constraints. Thus SIC addresses the constraint satisfiability problem during the schema design phase of a database. SIC combines two systems, a reasoning component and an interactive visual interface. This paper outlines the functionality of both components and the theoretical background and implementation aspects of the reasoning component. | [
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68 | 4 | Conveying Routes: Multimodal Generation and Spatial Intelligence In Embodied Conversational Agents In creating an embodied conversational agent (ECA) capable of conveying routes, it is necessary to understand how to present spatial information in an effective and natural manner. When conveying routes to someone, a person uses multiple modalities e.g., speech, gestures, and reference to a map to present information, and it is important to know precisely how these modalities are coordinated. With an understanding of how humans present spatial intelligence to give directions, it is then possible to create an ECA with similar capabilities. Two empirical studies were carried out to observe natural human-to-human direction-giving interactions. From the results, a direction-giving model was created, and then implemented in the MACK (Media Lab Autonomous Conversational Kiosk) system. | [
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69 | 4 | The CyberShoe: A Wireless Multisensor Interface for a Dancer's Feet : As a bridge between our interest in Wearable Computer systems and new performance interfaces for digital music, we have built a highly instrumented pair of sneakers for interactive dance. These shoes each measure 16 different, continuous parameters expressed by each foot and are able to transmit them wirelessly to a base station placed well over 30 meters away, updating all values up to 60 times per second. This paper describes our system, illustrates its performance, and outlines a few musical mappings that we have created for demonstrations in computer-augmented dance. ____________________________________ Electronic sensors have been incorporated into footwear for several different applications over the last several years. Employing force-sensing resistor arrays or pixelated capacitive sensing, insoles with very dense pressure sampling have been developed for research at the laboratories of footwear manufacturers and pediatric treatment facilities (Cavanaugh, et. al., 1992). Alth... | [
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70 | 3 | An Overview of Active Information Gathering in InfoSleuth InfoSleuth is a system of collaborating software agents that can be configured to perform many different information management activities in a distributed environment. InfoSleuth agents advertise semantic constraints about themselves to InfoSleuth brokers using a global domain ontology. When queried, a broker reasons over these constraints to determine the minimal set of agents that can provide a solution to the query. InfoSleuth's architecture is based on a generic agent shell that provides basic agent communication behaviors over a subset of Knowledge Query Manipulation Language. Individual agents are subclasses of this generic shell that provide specific kinds of functionality. InfoSleuth agents perform a number of complex query activities that require resolving ontology-based queries over dynamically changing, distributed, heterogeneous resources, including distributed query, location-independent single-resource updates, event monitoring by means of subscription/notification servi... | [
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71 | 3 | Logical Transactions and Serializability The concept of logic databases can serve as a clear and expressive foundation of various information systems. However, the classical logic language only refers to a single database state, although in modern information systems it is necessary to take the dynamics into account. For this purpose, several update languages were proposed, among them [1, 3, 4, 8, 9, 11], which allow to specify complex transitions from one database state to another. From the evaluation point of view, a complex state transition can and should be considered as a transaction. Up to now, the isolation property of transactions has been poorly addressed in the context of logic update languages, although it is an important problem even for classical, sequential transactions (see [2] for instance). In this paper we investigate how the serializability of logical transactions can be supported and what this means for the implementation of a transaction manager. 1 Introduction and Motivation In [11, 12] we propose an up... | [] | Train |
72 | 3 | Time Responsive Indexing Schemes for Moving Points We develop new indexing schemes for storing a set of points in one or two dimensions, each moving along a linear trajectory, so that a range query at a given future time t q can be answered efficiently. The novel feature of our indexing schemes is that the number of I/Os required to answer a query depends not only on the size of the data set and on the number of points in the answer but also on the difference between t q and the current time; queries close to the current time are answered fast, while queries that are far away in the future or in the past may take more time. Center for Geometric Computing, Department of Computer Science, Duke University, Durham, NC 27708, USA. Supported in part by Army Research Office MURI grant DAAH04-96-1-0013, by a Sloan fellowship, by NSF grants EIA--9870724, EIA--997287, and CCR--9732787, and by grant from the U.S.-Israeli Binational Science Foundation. Email: pankaj@cs.duke.edu. y Center for Geometric Computing, Department of Computer Sci... | [
54,
228,
341,
1024,
1256,
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73 | 1 | Inference and Learning in Hybrid Bayesian Networks We survey the literature on methods for inference and learning in Bayesian Networks composed of discrete and continuous nodes, in which the continuous nodes have a multivariate Gaussian distribution, whose mean and variance depends on the values of the discrete nodes. We also briefly consider hybrid Dynamic Bayesian Networks, an extension of switching Kalman filters. This report is meant to summarize what is known at a sufficient level of detail to enable someone to implement the algorithms, but without dwelling on formalities. 1 1 Introduction We discuss Bayesian networks (BNs [Jen96]) in which each node is either discrete or continuous, scalar or vector-valued, and in which the joint distribution over all the nodes is Conditional Gaussian (CG) [LW89, Lau92] i.e., for each instantiation i of the discrete nodes Y, the distribution over the continuous nodes X has the form f(xjY = i) = N (x; ~¯(i); \Sigma(i)), where N () represents a multivariate Gaussian (MVG) or Normal density. (Note... | [
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74 | 4 | EQUIP: a Software Platform for Distributed Interactive Systems EQUIP is a new software platform designed and engineered to support the development and deployment of distributed interactive systems, such as mixed reality user interfaces that combine distributed input and output devices to create a coordinated experience. EQUIP emphasises: cross-language development (currently C++ and Java), modularisation, extensibility, interactive performance, and heterogeneity of devices (from handheld devices to large servers and visualisation machines) and networks (including both wired and wireless technologies). A key element of EQUIP is its shared data service, which combines ideas from tuplespaces, general event systems and collaborative virtual environments. This data service provides a uniquely balanced treatment of state and event-based communication. It also supports distributed computation -- through remote class loading -- as well as passive data distribution. EQUIP has already been used in several projects within the EQUATOR Interdisciplinary Research Collaboration (IRC) in the UK, and is freely available in source form (currently known to work on Windows, IRIX and MacOS-X platforms). | [
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75 | 5 | Optimising Propositional Modal Satisfiability for Description Logic Subsumption . Effective optimisation techniques can make a dramatic difference in the performance of knowledge representation systems based on expressive description logics. Because of the correspondence between description logics and propositional modal logic many of these techniques carry over into propositional modal logic satisfiability checking. Currently-implemented representation systems that employ these techniques, such as FaCT and DLP, make effective satisfiable checkers for various propositional modal logics. 1 Introduction Description logics are a logical formalism for the representation of knowledge about individuals and descriptions of individuals. Description logics represent and reason with descriptions similar to "all people whose friends are both doctors and lawyers" or "all people whose children are doctors or lawyers or who have a child who has a spouse". The computations performed by systems that implement description logics are based around determining whether one descriptio... | [
645
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76 | 5 | A Gesture Interface for Human-Robot-Interaction We present a person-independent gesture interface implemented on a real robot which allows the user to give simple commands ,e.g., how to grasp an object and where to put it. The gesture analysis relies on realtime tracking of the user's hand and a re\Thetaned analysis of the hand's shape in the presence of varying complex backgrounds. 1. Introduction Robots of the future will interact with humans in a natural way. They will understand spoken and gestural commands and will articulate themselves by speech and gesture. We are especially interested in gestural interfaces for robots operating in uncontrolled real world environments. This imposes several constraints on human-robot-interaction as a special case of human-computer-interaction: 1. The robot visual system must cope with variable and possibly complex backgrounds. A system requiring uniform background is not exible enough for real world applications. 2. The system must be person independent. Many users should be able to operate ... | [
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77 | 3 | Improving Data Cleaning Quality using a Data Lineage Facility The problem of data cleaning, which consists of removing inconsistencies and errors from original data sets, is well known in the area of decision support systems and data warehouses. However, for some applications, existing ETL (Extraction Transformation Loading) and data cleaning tools for writing data cleaning programs are insufficient. One important challenge with them is the design of a data flow graph that effectively generates clean data. A generalized difficulty is the lack of explanation of cleaning results and user interaction facilities to tune a data cleaning program. This paper presents a solution to handle this problem by enabling users to express user interactions declaratively and tune data cleaning programs. 1 | [
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78 | 3 | Maude: Specification and Programming in Rewriting Logic Maude is a high-level language and a high-performance system supporting executable specification and declarative programming in rewriting logic. Since rewriting logic contains equational logic, Maude also supports equational specification and programming in its sublanguage of functional modules and theories. The underlying equational logic chosen for Maude is membership equational logic, that has sorts, subsorts, operator overloading, and partiality definable by membership and equality conditions. Rewriting logic is reflective, in the sense of being able to express its own metalevel at the object level. Reflection is systematically exploited in Maude endowing the language with powerful metaprogramming capabilities, including both user-definable module operations and declarative strategies to guide the deduction process. This paper explains and illustrates with examples the main concepts of Maude's language design, including its underlying logic, functional, system and object-oriented modules, as well as parameterized modules, theories, and views. We also explain how Maude supports reflection, metaprogramming and internal strategies. The paper outlines the principles underlying the Maude system implementation, including its semicompilation techniques. We conclude with some remarks about applications, work on a formal environment for Maude, and a mobile language extension of Maude. | [
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79 | 3 | Virtual Notepad: Handwriting in Immersive VR We present Virtual Notepad, a collection of interface tools that allows the user to take notes, annotate documents and input text using a pen, while still immersed in virtual environments (VEs). Using a spatially-tracked, pressure-sensitive graphics tablet, pen and handwriting recognition software, Virtual Notepad explores handwriting as a new modality for interaction in immersive VEs. This paper reports details of the Virtual Notepad interface and interaction techniques, discusses implementation and design issues, reports the results of initial evaluation and overviews possible applications of virtual handwriting. 1. Introduction Writing is a ubiquitous everyday activity. We jot down ideas and memos, scribble comments in the margins of a book or an article, annotate blueprints and design plans. Using computers, we type documents, complete forms and enter database queries. However, writing, taking notes or entering text in immersive VEs is almost impossible. Cut off from conventional... | [
1584,
2014
] | Train |
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