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the problem of estimating parameters of selected populations has wide practical applications in estimation of experimental data in agriculture , industry and medicine .some of the real world applications of this theory are the problem of estimating the average yield of a selected variety of plant with maximum yield ( k... | we introduce the problem of estimation of the parameters of a dynamically selected population in an infinite sequence of random variables and provide its application in the statistical inference based on record values from a non - stationary scheme . we develop unbiased estimation of the parameters of the dynamically s... |
in this paper , we study the temporal behavior of the distribution of stock prices for 24 stocks in the dow jones industrial average ( djia ) .this is done using a new method of measuring changes in the volatility and drifts of stocks with time . when this method is applied to time - series constructed from the daily c... | while the use of volatilities is pervasive throughout finance , our ability to determine the instantaneous volatility of stocks is nascent . here , we present a method for measuring the temporal behavior of stocks , and show that stock prices for 24 djia stocks follow a stochastic process that describes an efficiently ... |
the goal of the development of the code was to have a simple and efficient tool for the computation of adiabatic oscillation frequencies and eigenfunctions for general stellar models , emphasizing also the accuracy of the results .not surprisingly , given the long development period , the simplicity is now less evident... | development of the aarhus adiabatic pulsation code started around 1978 . although the main features have been stable for more than a decade , development of the code is continuing , concerning numerical properties and output . the code has been provided as a generally available package and has seen substantial use at a... |
it was game theory research , seeking screening strategies to prevent the counterfeiting of websites i.e. phishing attacks .various ways for websites to counterfeit installed software behaviour were studied . in full screen mode , it was found that , browsers can counterfeit almost anything , including blue screens of ... | phishing attacks occur because of a failure of computer users to authenticate bob . the computer user s role , her job , is to authenticate bob . nobody else can carry out this task . i researched the ability of browsers to counterfeit the behaviour of installed software . the objective was to find a signalling strateg... |
inferring macroscopic properties of physical systems from their microscopic description is an ongoing work in many disciplines of physics , like condensed matter , ultra cold atoms or quantum chromo dynamics .the most drastic changes in the macroscopic properties of a physical system occur at phase transitions , which ... | we employ unsupervised machine learning techniques to learn latent parameters which best describe states of the two - dimensional ising model and the three - dimensional xy model . these methods range from principal component analysis to artificial neural network based variational autoencoders . the states are sampled ... |
functional data are more and more frequently involved in statistical problems . developping statistical methods in this special frameworkhas been popularized during the last few years , particularly with the monograph by ramsay & silverman ( 2005 ) .more recently , new developments have been carried out in order to pro... | we consider the problem of predicting a real random variable from a functional explanatory variable . the problem is attacked by mean of nonparametric kernel approach which has been recently adapted to this functional context . we derive theoretical results by giving a deep asymptotic study of the behaviour of the esti... |
automation of financial and legal processes requires enforcement of confidentiality and integrity of transactions . for practical integration with the existing manual systems , such enforcement should be transparent to users .for instance , a person continually signs paper - based documents ( e.g. , bank checks ) by ha... | an offline signature - based fuzzy vault ( osfv ) is a bio - cryptographic implementation that uses handwritten signature images as biometrics instead of traditional passwords to secure private cryptographic keys . having a reliable osfv implementation is the first step towards automating financial and legal authentica... |
quantum computing based on qubits has attracted considerable attention ( see , e.g. , ) .there are several candidates to realize quantum computers , such as using nuclear spins in molecules , photons , trapped ions , superconducting circuit and quantum dots ( see , e.g. , ) .however , it is still a great challenge to b... | using three coupled harmonic oscillators , we have recently proposed [ arxiv:1007.4338 ] an alternative approach for quantum factorization of an integer . however , the probability of obtaining the factors becomes low when this number is large . here , we circumvent this limitation by using a new iterative method which... |
the information contained by an individual finite object ( like a finite binary string ) is objectively measured by its kolmogorov complexity the length of the shortest binary program that computes the object .such a shortest program contains no redundancy : every bit is information ; but is it meaningful information ?... | the information in an individual finite object ( like a binary string ) is commonly measured by its kolmogorov complexity . one can divide that information into two parts : the information accounting for the useful regularity present in the object and the information accounting for the remaining accidental information ... |
extensible markup language ( xml ) has reached a great success in the internet era .xml documents are similar to html documents , but do not restrict users to a single vocabulary , which offers a great deal of flexibility to represent information . to define the structure of documents within a certain vocabulary , sche... | xml and xml schema are widely used in different domains for the definition of standards that enhance the interoperability between parts exchanging information through the internet . the size and complexity of some standards , and their associated schemas , have been growing with time as new use case scenarios and data ... |
many cardiovascular diseases such as due to the arterial occlusion is one of the leading cause of death world wide .the partial occlusion of the arteries due to stenotic obstruction not only restrict the regular blood flow but also characterizes the hardening and thickening of the arterial wall .however , the main caus... | this paper presents a theoretical study of blood flow through a tapered and overlapping stenosed artery under the action of an externally applied magnetic field . the fluid ( blood ) medium is assumed to be porous in nature . the variable viscosity of blood depending on hematocrit ( percentage volume of erythrocytes ) ... |
the question about how a piece of information ( a virus , a rumor , an opinion , etc ., ) is globally spread over a network , and which ingredients are necessary to achieve such a success , has motivated much research recently .the reason behind this interest is that identifying key aspects of spreading phenomena facil... | social media have provided plentiful evidence of their capacity for information diffusion . fads and rumors , but also social unrest and riots travel fast and affect large fractions of the population participating in online social networks ( osns ) . this has spurred much research regarding the mechanisms that underlie... |
pablo picasso `` i paint objects as i think them , not as i see them '' recently , generative adversarial networks ( gans ) have shown significant promise in synthetically generate natural images using the mnist , cifar-10 , cub-200 and lfw datasets . however, we could notice that all these datasets have some common c... | this paper proposes an extension to the generative adversarial networks ( gans ) , namely as agan to synthetically generate more challenging and complex images such as artwork that have abstract characteristics . this is in contrast to most of the current solutions that focused on generating natural images such as room... |
in recent years there have been significant advances in the tomographic characterization of materials . as a result , it is now possible to carry out detailed investigations of the 3d grain structures of polycrystalline materials ; see , e.g. , .a fundamental ingredient in any such investigation is a suitable quantitat... | the analysis of polycrystalline materials benefits greatly from accurate quantitative descriptions of their grain structures . laguerre tessellations approximate such grain structures very well . however , it is a quite challenging problem to fit a laguerre tessellation to tomographic data , as a high - dimensional opt... |
when complex systems join to form even more complex systems , the interaction of the constituent subsystems is highly random .the complex stochastic interactions among these subsystems are commonly quantified by calculating the cross - correlations . this method has been applied in systems ranging from nanodevices , at... | we propose a modified time lag random matrix theory in order to study time lag cross - correlations in multiple time series . we apply the method to 48 world indices , one for each of 48 different countries . we find long - range power - law cross - correlations in the absolute values of returns that quantify risk , an... |
rules express general knowledge about actions or conclusions in given circumstances and also principles in given domains . in the if - then format , rules are an easy way to represent cognitive processes in psychology and a useful means to encode expert knowledge . in another perspective , rules are important because t... | in this paper , we introduce a new machine learning theory based on multi - channel parallel adaptation for rule discovery . this theory is distinguished from the familiar parallel - distributed adaptation theory of neural networks in terms of channel - based convergence to the target rules . we show how to realize thi... |
langevin dynamics is a modeling technique , in which the motion of a set of massive bodies in the presence of a bath of smaller solvent particles is directly integrated , while the dynamics of the solvent are `` averaged out '' .this approximation may lead to a dramatic reduction in computational cost compared to `` ex... | generalized langevin dynamics ( gld ) arise in the modeling of a number of systems , ranging from structured fluids that exhibit a viscoelastic mechanical response , to biological systems , and other media that exhibit anomalous diffusive phenomena . molecular dynamics ( md ) simulations that include gld in conjunction... |
most solid tumors eventually establish colonies in distant anatomical locations ; when these colonies become clinically detectable , they are called macrometastasis . while often there is a large burden from primary tumors , it is in fact metastatic disease that is responsible for most cancer fatalities .the creation o... | metastasis is the process by which cells from a primary tumor disperse and form new tumors at distant anatomical locations . the treatment and prevention of metastatic cancer remains an extremely challenging problem . this work introduces a novel biologically motivated objective function to the radiation optimization c... |
in spite of the growing recognition that physics skills `` scholastic rigor , analytical thinking , quantitative assessment , and the analysis of complex systems '' are important for biology and pre - medical students , these students often arrive in physics classes skeptical about the relevance of physics to their ac... | three , interrelated biologically - relevant examples of biased random walks are presented : ( 1 ) a model for dna melting , modelled as dna unzipping , which provides a way to illustrate the role of the boltzmann factor in a venue well - known to biology and pre - medical students ; ( 2 ) the activity of helicase moto... |
data compression is performed in all types of data requiring storage and transmission .it preserves space , energy and bandwidth , while representing the data in most efficient way [ 1 - 4 ] .there are numerous coding algorithms used for compression in various applications [ 1 - 3,5 - 18 ] .some of them are optimal [ 4... | the paper presents a binarization scheme that converts non - binary data into a set of binary strings . at present , there are many binarization algorithms , but they are optimal for only specific probability distributions of the data source . overcoming the problem , it is shown in this paper that the presented binari... |
for physicists physics is a permanent inspiration for new discoveries .however , non - physicists often consider physics as a boring and old discipline , detached from everyday life .public often fails to realize the consequences of research in everyday applications , so it often considers the academic research as a wa... | the paper presents a teaching module about liquid crystals . since liquid crystals are linked to everyday student experiences and are also a topic of a current scientific research , they are an excellent candidate of a modern topic to be introduced into education . we show that liquid crystals can provide a _ file roug... |
in recent years , the theoretical and experimental use of quantum systems to store , transmit and process information has spurred the study of how much of classical information theory can be extended to the new territory of quantum information and , vice versa , how much novel strategies and concepts are needed that ha... | in classical information theory , entropy rate and algorithmic complexity per symbol are related by a theorem of brudno . in this paper , we prove a quantum version of this theorem , connecting the von neumann entropy rate and two notions of quantum kolmogorov complexity , both based on the shortest qubit descriptions ... |
long before the development of cryptography and encryption , one of humankind s best techniques of secretly delivering a message was to hide the fact that a message was even delivered at all . a well - known example of this is from ancient times where one person would shave another s head and write a message on it .it ... | we present truly ultimate limits on covert quantum communication by exploiting quantum - mechanical properties of the minkowski vacuum in the quantum field theory framework . our main results are the following : we show how two parties equipped with unruh - dewitt detectors can covertly communicate at large distances w... |
the imaging atmospheric cherenkov technique ( iact ) was developed at the fred lawrence whipple observatory ( flwo ) resulting in the first very high energy ( vhe ; e 100 gev ) detection of the crab nebula in 1989 . in the twenty years since that first publicationthere have been vhe detections of over 100 objects inclu... | the first veritas telescope was installed in 2002 - 2003 at the fred lawrence whipple observatory and was originally operated as a prototype instrument . subsequently the decision was made to locate the full array at the same site , resulting in an asymmetric array layout . as anticipated , this resulted in less than o... |
_ iscsi _ is a protocol designed to transport scsi commands over a tcp / ip network .+ _ iscsi _ can be used as a building block for network storage using existing ip infrastructure in a lan / wan environment .it can connect different types of block - oriented storage devices to servers .+ _ iscsi _ was initially stand... | we report on our investigations on some technologies that can be used to build disk servers and networks of disk servers using commodity hardware and software solutions . it focuses on the performance that can be achieved by these systems and gives measured figures for different configurations . it is divided into tw... |
in wireless networks , radio signals can be overheard by unauthorized users due to the broadcast nature of wireless medium , which makes the wireless communication systems vulnerable to eavesdropping attack .secret key encryption techniques have been widely used to prevent eavesdropping and ensure the confidentiality o... | due to the broadcast nature of wireless medium , wireless communication is extremely vulnerable to eavesdropping attack . physical - layer security is emerging as a new paradigm to prevent the eavesdropper from interception by exploiting the physical characteristics of wireless channels , which has recently attracted a... |
bayesian inference using markov chain monte carlo simulation methods is used extensively in statistical applications . in this approach ,the parameters are generated from a proposal distribution , or several such proposal distributions , with the generated proposals accepted or rejected using the metropolis - hastings ... | our article is concerned with adaptive sampling schemes for bayesian inference that update the proposal densities using previous iterates . we introduce a copula based proposal density which is made more efficient by combining it with antithetic variable sampling . we compare the copula based proposal to an adaptive pr... |
selection , random genetic drift and mutations are the processes underlying darwinian evolution . for a long timepopulation geneticists have analyzed the dynamics in the simplest setting consisting of two genotypes evolving under these processes . in those studies, a genotype represents an individual s genetic makeup ,... | evolution is simultaneously driven by a number of processes such as mutation , competition and random sampling . understanding which of these processes is dominating the collective evolutionary dynamics in dependence on system properties is a fundamental aim of theoretical research . recent works quantitatively studied... |
life is intimately related to movement on many different time and length scales , from molecular movements to the motility of cells and organisms .one type of movement which is ubiquitous on the molecular and cellular scale , although not specific to the organic world , is brownian motion or passive diffusion : biomole... | molecular motors power directed transport of cargoes within cells . even if a single motor is sufficient to transport a cargo , motors often cooperate in small teams . we discuss the cooperative cargo transport by several motors theoretically and explore some of its properties . in particular we emphasize how motor tea... |
every physically relevant computational model must be mapped into physical space - time and _ vice versa _ . in this line of thought , von neumann s self - reproducing cellular automata have been envisioned by zuse and other researchers as `` calculating space ; '' i.e. , as a locally connected grid of finite automata ... | two novel computing models based on an infinite tessellation of space - time are introduced . they consist of recursively coupled primitive building blocks . the first model is a scale - invariant generalization of cellular automata , whereas the second one utilizes self - similar petri nets . both models are capable o... |
in recent years , advances in quantum control have emerged through the introduction of appropriate and powerful tools coming from mathematical control theory and by the use of sophisticated experimental techniques to shape the corresponding control fields .all these efforts have lead nowadays to an unexpected and satis... | we propose a new formulation of optimal and local control algorithms which enforces the constraint of time - integrated zero - area on the control field . the fulfillment of this requirement , crucial in many physical applications , is mathematically implemented by the introduction of a lagrange multiplier aiming at pe... |
the identification of a deterministic linear operator from the operator s response to a probing signal is an important problem in many fields of engineering .concrete examples include system identification in control theory and practice , the measurement of dispersive communication channels , and radar imaging .it is n... | we consider the problem of identifying a linear deterministic operator from its response to a given probing signal . for a large class of linear operators , we show that stable identifiability is possible if the total support area of the operator s spreading function satisfies . this result holds for an arbitrary ( pos... |
restarts have been shown to boost the performance of backtracking sat solvers ( see for example , ) . a restart strategy ( ,, , ... ) is a sequence of restart lengths that the solver follows in the course of its execution .the solver first performs steps ( in case of sat solvers a step is usually a conflict ) .if a sol... | restart strategies are an important factor in the performance of conflict - driven davis putnam style sat solvers . selecting a good restart strategy for a problem instance can enhance the performance of a solver . inspired by recent success applying machine learning techniques to predict the runtime of sat solvers , w... |
the advent of smartphones and tablets has made the use of touchscreen keyboards pervasive in modern society .however , the ubiquitous qwerty keyboard was not designed with the needs of a touchscreen keyboard in mind , namely accuracy and speed .the introduction of gesture or stroke - based input methods significantly i... | gesture typing is a method of text entry that is ergonomically well - suited to the form factor of touchscreen devices and allows for much faster input than tapping each letter individually . the qwerty keyboard was , however , not designed with gesture input in mind and its particular layout results in a high frequenc... |
wireless sensor networks ( wsns ) can be utilized as target tracking systems that detect a moving target , localize it and report its location to the sink .so far , the wsn - based tracking systems have found various applications , such as battlefield monitoring , wildlife monitoring , intruder detection , and traffic ... | this paper introduces algorithms for target tracking in wireless sensor networks ( wsns ) that enable reduction of data communication cost . the objective of the considered problem is to control movement of a mobile sink which has to reach a moving target in the shortest possible time . consumption of the wsn energy re... |
after more than two decades of investigations , black hole thermodynamics is still one of the most puzzling subjects in theoretical physics .one approach to studying the thermodynamical aspects of a black hole involves considering the evolution of quantum matter fields propagating on a classical ( curved ) background s... | in this work , we extend the analysis of brown and york to find the quasilocal energy in a spherical box in the schwarzschild spacetime . quasilocal energy is the value of the hamiltonian that generates unit magnitude proper - time translations on the box orthogonal to the spatial hypersurfaces foliating the schwarzsch... |
the distribution of wealth , income or company size is one of important issues not only in economics but also in econophysics . in these distributions ,a cumulative number obeys a power - law for which is larger than a certain threshold : this power - law and the exponent are called pareto s law and pareto index , resp... | employing profits data of japanese companies in 2002 and 2003 , we identify the non - gibrat s law which holds in the middle profits region . from the law of detailed balance in all regions , gibrat s law in the high region and the non - gibrat s law in the middle region , we kinematically derive the profits distributi... |
sharpe ratio has become a `` gold standard '' for measuring performance of hedge funds and other institutional investors ( this note uses the generic term `` portfolio '' ) .it is sometimes argued that it is applicable only to i.i.d .gaussian returns , but we will follow a common practice of ignoring such assumptions .... | a simple example shows that losing all money is compatible with a very high sharpe ratio ( as computed after losing all money ) . however , the only way that the sharpe ratio can be high while losing money is that there is a period in which all or almost all money is lost . this note explores the best achievable sharpe... |
the balance between excitatory and inhibitory elements is of great relevance for processes of self - organization in various neurological structures .synchronization is one prominent phenomenon that is critically influenced by the balance of excitation and inhibition and is itself an important mechanism involved in pro... | we investigate the combined effects of distributed delay and the balance between excitatory and inhibitory nodes on the stability of synchronous oscillations in a network of coupled stuart landau oscillators . to this end a symmetric network model is proposed for which the stability can be investigated analytically . ... |
imaging detector arrays based on transition edge sensors ( tes ) are a maturing technology for a range of both earth and space - base applications , such as infrared astronomy , x - ray astronomy , and material analysis .squid - based multiplexed readout is needed to obtain a detector noise limited readout chain .multi... | tes - based bolometer and microcalorimeter arrays with thousands of pixels are under development for several space - based and ground - based applications . a linear detector response and low levels of cross talk facilitate the calibration of the instruments . in an effort to improve the properties of tes - based detec... |
critical phenomena in anisotropic systems without equivalent nearest neighbors constitute an interesting research topic . a universal formula for percolation thresholds , that involves the dimension of the anisotropic lattice and an arithmetic average of the coordination number for different anisotropic lattices , has ... | we propose a simulation model to study the properties of directed percolation in two - dimensional ( 2d ) anisotropic random media . the degree of anisotropy in the model is given by the ratio between the axes of a semi - ellipse enclosing the bonds that promote percolation in one direction . at percolation , this simp... |
in many applications , in particular in the pricing of financial securities , we are interested in the effective computation by monte carlo methods of the quantity , where is a diffusion process and a given function .the monte carlo euler method consists of two steps .first , approximate the diffusion process by the eu... | this paper focuses on studying the multilevel monte carlo method recently introduced by giles [ _ oper . res . _ * 56 * ( 2008 ) 607617 ] which is significantly more efficient than the classical monte carlo one . our aim is to prove a central limit theorem of lindeberg feller type for the multilevel monte carlo method ... |
terrestrial planets and cores of giant planets are generally considered to have formed through accretion of many small bodies called planetesimals . to simulate accretion processes of planets ,two methods , which are complementary to each other , have been applied .the first one is -body simulations in which orbits of ... | we introduce a new particle - based hybrid code for planetary accretion . the code uses an -body routine for interactions with planetary embryos while it can handle a large number of planetesimals using a super - particle approximation , in which a large number of small planetesimals are represented by a small number o... |
ime - domain simulation is an important approach for power system dynamic analysis .however , the complete system model , or interchangeably the long - term stability model , typically includes different components where each component requires several differential and algebraic equations ( dae ) to represent , at the ... | in this paper , pseudo - transient continuation method has been modified and implemented in power system long - term stability analysis . this method is a middle ground between integration and steady state calculation , thus is a good compromise between accuracy and efficiency . pseudo - transient continuation method c... |
about ten years ago , a peculiar dynamical phenomenon was discovered in populations of identical phase oscillators : under nonlocal symmetric coupling , the coexistence of coherent ( synchronized ) and incoherent oscillators was observed .this highly counterintuitive phenomenon was given the name chimera state after th... | we have identified the occurrence of chimera states for various coupling schemes in networks of two - dimensional and three - dimensional hindmarsh - rose oscillators , which represent realistic models of neuronal ensembles . this result , together with recent studies on multiple chimera states in nonlocally coupled fi... |
in the quest for better wireless connectivity and higher data rates , the cellular network is becoming heterogeneous , featuring multiple types of base stations ( bss ) with different cell size .heterogeneity implies that the traditional strategies in cell planning , deployment and communication should be significantly... | wireless cellular networks evolve towards a heterogeneous infrastructure , featuring multiple types of base stations ( bss ) , such as femto bss ( fbss ) and macro bss ( mbss ) . a wireless device observes multiple points ( bss ) through which it can access the infrastructure and it may choose to receive the downlink (... |
the signals received by the antennas obey the stationary stochastic process and then ergodic process .the ergodic theory can be applied to the auto - correlation function for a spectrometer and the cross - correlation function for radio interferometer . under such conditions , weinreb ( 1963 )developed the first digita... | we established a new algorithm for correlation process in radio astronomy . this scheme consists of the 1st - stage fourier transform as a filter and the 2nd - stage fourier transform for spectroscopy . the `` ffx '' correlator stands for filter and fx architecture , since the 1st - stage fourier transform is performed... |
the multiple sequence alignment ( msa ) problem constitutes one of the fundamental research areas in bioinformatics . while at first sight it may seem a simple extension of the two - string alignment problem _ two strings good , four strings better _, for biologists , the multiple alignment of proteins or dna is crucia... | we proposed a probabilistic algorithm to solve the multiple sequence alignment problem . the algorithm is a simulated annealing ( sa ) that exploits the representation of the multiple alignment between sequences as a directed polymer in dimensions . within this representation we can easily track the evolution in the co... |
modulation level classification ( mlc ) is a process which detects the transmitter s digital modulation level from a received signal , using a priori knowledge of the modulation class and signal characteristics needed for downconversion and sampling . among many modulation classification methods ,a cumulant ( cm ) bas... | we present a novel modulation level classification ( mlc ) method based on probability distribution distance functions . the proposed method uses modified kuiper and kolmogorov - smirnov distances to achieve low computational complexity and outperforms the state of the art methods based on cumulants and goodness - of -... |
optimization is a challenging problem in economic analysis and risk management , which dates back to the seminal work of markowitz [ 1 ] .the main assumption is that the return of any financial asset is described by a random variable , whose expected mean and variance are assumed to be reliably estimated from historica... | we consider the problem of finding the efficient frontier associated with the risk - return portfolio optimization model . we derive the analytical expression of the efficient frontier for a portfolio of risky assets , and for the case when a risk - free asset is added to the model . also , we provide an r implementati... |
the study of changes in the natural world , dynamics , is divided among several distinct disciplines .thermodynamics , for example , considers changes between special states , the so - called states of equilibrium , and addresses the question of which final states can be reached from any given initial state .mechanics ... | i explore the possibility that the laws of physics might be laws of inference rather than laws of nature . what sort of dynamics can one derive from well - established rules of inference ? specifically , i ask : given relevant information codified in the initial and the final states , what trajectory is the system expe... |
in this paper we scratch an intelligent variable neighbourhood search ( int - vns ) aimed to achieve further improvements of a successful vns for the minimum labelling spanning tree ( mlst ) and the -labelled spanning forest ( ) problems .this approach integrates the basic vns with other complementary intelligence tool... | in this paper we describe an extension of the variable neighbourhood search ( vns ) which integrates the basic vns with other complementary approaches from machine learning , statistics and experimental algorithmic , in order to produce high - quality performance and to completely automate the resulting optimization st... |
urban vegetation is receiving a significant amount of attention from researchers in recent years .this interest stems from its impacts on the environment , affecting the pedestrian comfort and mitigating the negative health effects of the air pollution .microscale modelling using the computational fluid dynamics ( cfd ... | a dry deposition model suitable for use in the moment method has been developed . contributions from five main processes driving the deposition - brownian diffusion , interception , impaction , turbulent impaction , and sedimentation - are included in the model . the deposition model was employed in the moment method s... |
challenge when determining the performance of a block error - correcting code is to measure its bit - error rate ( ber ) , which quantifies the reliability of the system . in practice ,the ber estimation for a single code is simple , just send data and divide the errors committed among the total number of bits .however... | in this paper , a computation of the input - redundancy weight enumerator is presented . this is used to improve the theoretical approximation of the information bit and symbol error rate , in terms of the channel bit - error rate , in a block transmission through a discrete memoryless channel . since a bounded distanc... |
sex , which involves the alternation of meiosis and gamete fusion , is a rather inefficient means of self - propagation as compared to asexual reproduction , where offspring stem only from a mitotically produced cells .one of the most common reasons used to explain the origin and maintenance of sex is its ability to re... | why sex evolved and it prevails in nature remains one of the great puzzles of evolution . most biologists would explain that it promotes genetic variability , however this explanation suffers from several difficulties . what advantages might sex confer ? the present communication aims at certain investigations related ... |
we investigate different effects contributing to the determination of the optimal angle of release at shot put .standard text - book wisdom tells us that the optimal angle is , while measurements of world - class athletes typically give values of below . in table[ tab1 ] we show the data from the olympic games in 1972 ... | we determine the optimal angle of release in shot put . the simplest model - mostly used in textbooks - gives a value of , while measurements of top athletes cluster around . including simply the height of the athlete the theory prediction goes down to about for typical parameters of top athletes . taking further the c... |
the future power system will be modernized with advanced metering infrastructure , bilateral information communication network , and intelligent monitoring and control system to enable a smarter operation .the transformation to the smart grid is expected to facilitate the deep integration of renewable energy , improve... | aggregation of a large number of responsive loads presents great power flexibility for demand response . an effective control and coordination scheme of flexible loads requires an accurate and tractable model that captures their aggregate flexibility . this paper proposes a novel approach to extract the aggregate flexi... |
atlas will be a particle physics experiment at the future large hadron collider ( lhc ) , which is being built at cern and is expected to start operation in 2007 .the pixel detector is the innermost component of the atlas inner tracker . in the barrelthe detector modules are mounted on staves , while the modules in the... | the barrel part of the atlas pixel detector will consist of 112 carbon - carbon structures called `` staves '' with 13 hybrid detector modules being glued on each stave . the demands on the glue joints are high , both in terms of mechanical precision and thermal contact . to achieve this precision a custom - made semi ... |
the tumor suppressor p53 plays a central role in cellular responses to various stress , including oxidative stress , hypoxia , telomere erosion and dna damage . in unstressed cells ,p53 is kept at low level via its negative regulator mdm2 . under stressed conditions , such as dna damage, p53 is stabilized and activated... | dynamics of p53 is known to play important roles in the regulation of cell fate decisions in response to various stresses , and pdcd5 functions as a co - activator of p53 to modulate the p53 dynamics . in the present paper , we investigate how p53 dynamics are modulated by pdcd5 during the dna damage response using met... |
in his seminal work , luneburg derived a spherical optical lens with radially varying refractive index that focused a beam of parallel rays to a point at the opposite side of the lens ; a two dimensional variant is straightforward to deduce .of course this relies upon the governing equation being the helmholtz equation... | metamaterials are artificially structured media that can focus ( lensing ) or reroute ( cloaking ) waves , and typically this is developed for electromagnetic waves at millimetric down to nanometric scales or for acoustics or thin elastic plates at centimeter scales . extending the concepts of we show that the underlyi... |
if borrowers have only assets that when liquidated generate cash in a local currency different from the currency in which their debt is due , their default risk will be higher than in the one currency case , as a consequence of the additional exchange rate risk .the increase in default risk is reflected both in higher ... | intuitively , the default risk of a single borrower is higher when her or his assets and debt are denominated in different currencies . additionally , the default dependence of borrowers with assets and debt in different currencies should be stronger than in the one - currency case . by combining well - known models by... |
the _ heat kernel approach _ ( hka for short ) , which will be presented and discussed in this paper , is a systematic method to construct state price densities which are analytically tractable . to be precise on analytic tractability , we mean with this notion that bond prices can be calculated explicitly , and that c... | we construct default - free interest rate models in the spirit of the well - known markov funcional models : our focus is analytic tractability of the models and generality of the approach . we work in the setting of state price densities and construct models by means of the so called propagation property . the propaga... |
the problem of determining the angle at which a point mass launched from ground level with a given speed will reach a maximum distance is a standard exercise in mechanics .there are many possible ways of solving this problem , leading to the well - known answer of , producing a maximum range of , with being the free - ... | the problem of determining the angle at which a point mass launched from ground level with a given speed is a standard exercise in mechanics . similar , yet conceptually and calculationally more difficult problems have been suggested to improve student proficiency in projectile motion . the problem of determining the m... |
recently , a great deal of attention has been payed to wireless sensor networks whose nodes sample a physical phenomenon ( hereinafter referred to as field ) , i.e. , air temperature , light intensity , pollution levels or rain falls , and send their measurements to a central processing unit ( or _ sink _ node ) .the s... | environmental monitoring is often performed through a wireless sensor network , whose nodes are randomly deployed over the geographical region of interest . sensors sample a physical phenomenon ( the so - called field ) and send their measurements to a _ sink _ node , which is in charge of reconstructing the field from... |
the core object of our investigation is an _e. coli _ network representation of its combined gene regulation and metabolism , which can be thought of as functionally divided into three _ domains _ : the representation captures both gene regulatory and metabolic processes , with these processes being connected by an int... | the major biochemical networks of the living cell , the network of interacting genes and the network of biochemical reactions , are highly interdependent , however , they have been studied mostly as separate systems so far . in the last years an appropriate theoretical framework for studying interdependent networks has... |
in signal processing , a classical uncertainty principle limits the time - bandwidth product of a signal , where is the measure of the support of the signal , and is the measure of the support of its fourier transform ( cf ., e.g. , ) .a very elementary formulation of that principle is whenever and . in the inverse so... | starting with far field data of time - harmonic acoustic or electromagnetic waves radiated by a collection of compactly supported sources in two - dimensional free space , we develop criteria and algorithms for the recovery of the far field components radiated by each of the individual sources , and the simultaneous re... |
a substantial part of the energy carried by the solar wind can be transfered into the terrestrial magnetosphere and it is associated with the passage of southward directed interplanetary magnetic fields , bs , by the earth for sufficiently long intervals of time . discussed the energy transfer process as a conversion o... | this paper describes a methodology ( or treatment ) to establish a representative signal of the global magnetic diurnal variation based on a spatial distribution in both longitude and latitude of a set of magnetic stations as well as their magnetic behavior on a time basis . for that , we apply the principal component ... |
mathematical models are used throughout infectious disease epidemiology to understand the dynamical processes that shape patterns of disease . while early models did not include complex population structure , modeling approaches now frequently let the epidemic spread take place on a network , which enables greater rea... | networks of contacts capable of spreading infectious diseases are often observed to be highly heterogeneous , with the majority of individuals having fewer contacts than the mean , and a significant minority having relatively very many contacts . we derive a two - dimensional diffusion model for the full temporal behav... |
three models which study the stochastic behaviour of the prices of commodities that take into account several aspects of possible influences on the prices were proposed by e schwartz in the late nineties . in the simplest model ( the so - called one - factor model )schwartz assumed that the logarithm of the spot price ... | we consider the one - factor model of commodities for which the parameters of the model depend upon the stock price or on the time . for that model we study the existence of group - invariant transformations . when the parameters are constant , the one - factor model is maximally symmetric . that also holds for the tim... |
lifetime distribution represents an attempt to describe , mathematically , the length of the life of a system or a device .lifetime distributions are most frequently used in the fields like medicine , engineering etc .many parametric models such as exponential , gamma , weibull have been frequently used in statistical ... | in this paper , we introduce a new distribution generated by lindley random variable which offers a more flexible model for modelling lifetime data . various statistical properties like distribution function , survival function , moments , entropy , and limiting distribution of extreme order statistics are established ... |
with the growth of internet the relationship between online information and financial markets has become a subject of ever increasing interest .online information offers with respect to its origin and purpose and reflects either interest of some profile of users in the form of query or knowledge about certain topic in ... | motivated by recent financial crises significant research efforts have been put into studying contagion effects and herding behaviour in financial markets . much less has been said about influence of financial news on financial markets . we propose a novel measure of collective behaviour in financial news on the web , ... |
space time explorer & quantum equivalence space test ( ste - quest ) is a medium - sized mission candidate for launch in 2022/2024 in the cosmic vision programme of the european space agency .after recommendation by the space science advisory committee , it was selected to be first studied by esa , followed by two para... | ste - quest is a fundamental science mission which is considered for launch within the cosmic vision programme of the european space agency ( esa ) . its main scientific objectives relate to probing various aspects of einstein s theory of general relativity by measuring the gravitational red - shift of the earth , the ... |
the paper is concerned with the spectral and computational analysis of effective preconditioners for linear systems arising from finite element approximations to the elliptic convection - diffusion problem with domain of .we consider a model setting in which the structured finite element partition is made by equi - lat... | the paper is devoted to the spectral analysis of effective preconditioners for linear systems obtained via a finite element approximation to diffusion - dominated convection - diffusion equations . we consider a model setting in which the structured finite element partition is made by equi - lateral triangles . under s... |
the design and characterization of strategies for controlling quantum dynamics is vital to a broad spectrum of applications within contemporary physics and engineering .these range from traditional coherent - control settings like high - resolution nuclear and molecular spectroscopy , to a variety of tasks motivated ... | we revisit the problem of switching off unwanted phase evolution and decoherence in a single two - state quantum system in the light of recent results on random dynamical decoupling methods [ l. viola and e. knill , phys . rev . lett . * 94 * , 060502 ( 2005 ) ] . a systematic comparison with standard cyclic decoupling... |
evolutionary algorithms are a type of general problem solvers that can be applied to many difficult optimization problems . because of their generality , these algorithms act similarly like swiss army knife that is a handy set of tools that can be used to address a variety of tasks . in general ,a definite task can be ... | evolutionary algorithms are good general problem solver but suffer from a lack of domain specific knowledge . however , the problem specific knowledge can be added to evolutionary algorithms by hybridizing . interestingly , all the elements of the evolutionary algorithms can be hybridized . in this chapter , the hybrid... |
signal reconstruction is usually formulated as a linear inverse problem where is the true signal , is an real matrix , is the observed data and represents the random noise . over the last decade, sparse reconstruction has received great attentions . in general ,the task of sparse reconstruction is to find a sparse from... | the constrained regularization plays an important role in sparse reconstruction . a widely used approach for solving this problem is the penalty method , of which the least square penalty problem is a special case . however , the connections between global minimizers of the constrained problem and its penalty problem h... |
in many applications such as complex system design or hyperparameter calibration for learning systems , the goal is to optimize some output value of a non - explicit function with as few evaluations as possible .indeed , in such contexts , one has access to the function values only through numerical evaluations by simu... | in this paper , we consider the problem of maximizing an _ unknown _ function over a compact and convex set using as few observations as possible . we observe that the optimization of the function essentially relies on learning the induced bipartite ranking rule of . based on this idea , we relate global optimization t... |
of agent and the cooperation between agents in multi - agent system ( mas ) , a framework , named distributed constraint optimization problem ( dcop ) in terms of constraints that are known and enforced by distinct agents comes into being with it .in last decade , the research effort of dcop has been dedicated on the f... | multi - agent systems ( mas ) is able to characterize the behavior of individual agent and the interaction between agents . thus , it motivates us to leverage the distributed constraint optimization problem ( dcop ) , a framework of modeling mas , to solve the user association problem in heterogeneous networks ( hetnet... |
the accumulated experience in helioseismology of inverting mode frequency data provides a good starting point for asteroseismic inversion . in some rather superficial waysthe circumstances of the two may seem very different : helioseismologists can use many more mode frequencies than will ever be possible for a more di... | some issues of inverting asteroseismic frequency data are discussed , including the use of model calibration and linearized inversion . an illustrative inversion of artificial data for solar - type stars , using least - squares fitting of a small set of basis functions , is presented . a few details of kernel construct... |
homodyne detection is an experimental method that is used to reconstruct quantum states of coherent light by repeatedly measuring a discrete set of field quadratures .usually , a very high detection efficiency and ad - hoc designed apparatuses with low electronic noise are required .new methods capable of discriminatin... | standard quantum state reconstruction techniques indicate that a detection efficiency of is an absolute threshold below which quantum interferences can not be measured . however , alternative statistical techniques suggest that this threshold can be overcome at the price of increasing the statistics used for the recons... |
the term ` stochastic resonance ' was introduced in the early 80s ( see and ) in the study of periodic advance of glaciers on earth .the stochastic resonance is the effect of nonmonotone dependence of the response of a system on the noise when this noise ( for instance the temperature ) is added to a periodic input sig... | a subthreshold signal is transmitted through a channel and may be detected when some noise with known structure and proportional to some level is added to the data . there is an optimal noise level , called stochastic resonance , that corresponds to the highest fisher information in the problem of estimation of the sig... |
while most readers will be familiar with the notion of _ feedback control _, for completeness we begin by defining this term .feedback control is the process of monitoring a physical system , and using this information as it is being obtained ( in real time ) to apply forces to the system so as to control its dynamics ... | we give an introduction to feedback control in quantum systems , as well as an overview of the variety of applications which have been explored to date . this introductory review is aimed primarily at control theorists unfamiliar with quantum mechanics , but should also be useful to quantum physicists interested in app... |
graphical representations of complex multivariate systems are increasingly prevalent within systems biology . in general a graph or _ network _ is characterised by a set of vertices ( typically associated with molecular species ) and a set of edges , whose interpretation will be context - specific .in many situations t... | graphical models are widely used to study complex multivariate biological systems . network inference algorithms aim to reverse - engineer such models from noisy experimental data . it is common to assess such algorithms using techniques from classifier analysis . these metrics , based on ability to correctly infer ind... |
fifty years after the pioneering discoveries of fermi , pasta and ulam , the paradigm of coherent structures has proven itself one of the most fruitful ones of nonlinear science .fronts , solitons , solitary waves , breathers , or vortices are instances of such coherent structures of relevance in a plethora of applicat... | we study the phenomenon of length scale competition , an instability of solitons and other coherent structures that takes place when their size is of the same order of some characteristic scale of the system in which they propagate . working on the framework of nonlinear klein - gordon models as a paradigmatic example ... |
nowadays , the application of information technology is a vital part of our daily life .people around the globe use billions of mobile devices daily and spend more times on using these digital devices than ever . sharing our opinions in social networks , searching the web , twitting , purchasing online products , parti... | the increasing application of social and human - enabled systems in people s daily life from one side and from the other side the fast growth of mobile and smart phones technologies have resulted in generating tremendous amount of data , also referred to as big data , and a need for analyzing these data , i.e. , big da... |
one of the key challenges in neuroscience is how the human brain activities can be mapped to the different brain tasks . as a conjunction between neuroscience and computer science , multi - voxel pattern analysis ( mvpa ) addresses this question by applying machine learning methods on task - based functional magnetic r... | a universal unanswered question in neuroscience and machine learning is whether computers can decode the patterns of the human brain . multi - voxels pattern analysis ( mvpa ) is a critical tool for addressing this question . however , there are two challenges in the previous mvpa methods , which include decreasing spa... |
cellular automata with complex behavior exhibit dynamical patterns that can be interpreted as the movement of particles through a physical medium .these particles are interpretable as loci for information storage , and their movement through space is interpretable as information transfer .the collisions of these partic... | we propose the characterization of binary cellular automata using a set of behavioral metrics that are applied to the minimal boolean form of a cellular automaton s transition function . these behavioral metrics are formulated to satisfy heuristic criteria derived from elementary cellular automata . behaviors character... |
a growing literature has presented empirical findings of the persistent impact of trade activities on economic growth and poverty reduction ( portugal - perez,,, , ackah , ) . besides discussing on the relation between trade and development , they also report on the growth by destination hypothesis , accordingto which ... | this paper is a contribution to interweaving two lines of research that have progressed in separate ways : network analyses of international trade and the literature on african trade and development . gathering empirical data on african countries has important limitations and so does the space occupied by african count... |
as the amount of available sequence data from genomes or proteoms rapidly grows , one is confronted with the problem that , for a given set of taxa , tree topologies relating homologous sequences of these taxa can ( and in practice often will ) differ from the each other , depending on which locus in the genome or whic... | in this article we propose a new method , which we name ` quartet neighbor joining ' , or ` quartet - nj ' , to infer an unrooted species tree on a given set of taxa from empirical distributions of unrooted quartet gene trees on all four - taxon subsets of . in particular , quartet - nj can be used to estimate a specie... |
the convection - diffusion model can be expressed mathematically , which is a semi linear parabolic partial differential equation .specially , we consider an initial value system of _ convection - diffusion _ equation in dimension as : ,\ ] ] together with the dirichlet boundary conditions : ,\ ] ] or neumann boundary ... | this paper deals with the numerical computations of two space dimensional time dependent _ parabolic partial differential equations _ by adopting adopting an optimal five stage fourth - order strong stability preserving runge - kutta ( ssp - rk54 ) scheme for time discretization , and three methods of differential quad... |
robot design deals with complexity in a manner similar to personal computers .robots have input / output devices that either provide output by acting in the environment or sensors that provide input . like pcs ,robot peripherals contain firmware ( device controllers ) to predictably and efficiently manage resources in ... | there is no dearth of new robots that provide both generalized and customized platforms for learning and research . unfortunately as we attempt to adapt existing software components , we are faced with an explosion of device drivers that interface each hardware platform with existing frameworks . we certainly gain the ... |
numerous techniques for forecasting electric energy consumption have been proposed in the last few decades . for operators , energy consumption ( load )forecast is useful in effectively managing power systems .consumers can also benefit from the forecasted information in order to yield maximum satisfaction .in addition... | due to imprecision and uncertainties in predicting real world problems , artificial neural network ( ann ) techniques have become increasingly useful for modeling and optimization . this paper presents an artificial neural network approach for forecasting electric energy consumption . for effective planning and operati... |
forecasting of seasonal rainfall , especially the summer monsoon , is important to the indian economy ( ) .seasonal forecasts of rainfall are made at the national - scale ( ) because monsoons are large scale phenomena and there is an association between all - india summer monsoon rainfall and aggregate impacts ( ) .how... | forecasts of monsoon rainfall for india are made at national scale . but there is spatial coherence and heterogeneity that is relevant to forecasting . this paper considers year - to - year rainfall change and annual extremes at sub - national scales . we use data mining techniques to gridded rain - gauge data for 1901... |
lease take a look at the images in the top row of fig .[ fig : fig1 ] .which object stands out the most ( i.e. , is the most salient one ) in each of these scenes ?the answer is trivial .there is only one object , thus it is the most salient one .now , look at the images in the third row .these scenes are much more com... | salient object detection or salient region detection models , diverging from fixation prediction models , have traditionally been dealing with locating and segmenting the most salient object or region in a scene . while the notion of most salient object is sensible when multiple objects exist in a scene , current datas... |
the prediction of microstructural evolution in response to thermo - mechanical loading is important for materials design , processing or thermomechanical fatigue phenomena .computational modeling of evolving texture in response to large plastic deformation and recrystallization has been studied extensively but less so... | a hybrid monte carlo ( hmc ) approach is employed to quantify the influence of inelastic deformation on the microstructural evolution of polycrystalline materials . this approach couples a time explicit material point method ( mpm ) for deformation with a calibrated monte carlo model for grain boundary motion . a rate ... |
since introduced by howard , the concept of the expected value of information has long been studied in the context of decision analysis and applied to various areas , such as medical decision making , environmental science and petroleum engineering .the expected value of information is defined as the expected increase ... | the expected value of partial perfect information ( evppi ) denotes the value of eliminating uncertainty on a subset of unknown parameters involved in a decision model . the evppi can be regarded as a decision - theoretic sensitivity index , and has been widely used for identifying relatively important unknown paramete... |
in many applications , the input and output of the controller are quantized signals .this is due to the physical properties of the actuators / sensors and the data - rate limitation of links connected to the controller .quantized control for linear time - invariant systems actively studied from various point of view , ... | this paper studies quantized control for discrete - time piecewise affine systems . for given stabilizing feedback controllers , we propose an encoding strategy for local stability . if the quantized state is near the boundaries of quantization regions , then the controller can recompute a better quantization value . f... |
in classical statistics , it is often assumed that the outcome of an experiment is precise and the uncertainty of observations is solely due to randomness . under this assumption ,numerical data are represented as collections of real numbers . in recent years , however , there has been increased interest in situations ... | many statistical data are imprecise due to factors such as measurement errors , computation errors , and lack of information . in such cases , data are better represented by intervals rather than by single numbers . existing methods for analyzing interval - valued data include regressions in the metric space of interva... |
estimation is a crucial application in the energy management system ( ems ) .the well - known static state estimation ( sse ) methods assume that the power system is operating in quasi - steady state , based on which the static states the voltage magnitude and phase angles of the buses are estimated by using scada and/... | kalman filters and observers are two main classes of dynamic state estimation ( dse ) routines . power system dse has been implemented by various kalman filters , such as the extended kalman filter ( ekf ) and the unscented kalman filter ( ukf ) . in this paper , we discuss two challenges for an effective power system ... |
synchronization describes the adjustment of rhythms of self - sustained oscillators due to their interaction .such collective behavior has important ramifications in myriad natural and laboratory systems ranging from conservation and pathogen control in ecology to applications throughout physics , chemistry , and engin... | we study ensembles of globally coupled , nonidentical phase oscillators subject to correlated noise , and we identify several important factors that cause noise and coupling to synchronize or desychronize a system . by introducing noise in various ways , we find a novel estimate for the onset of synchrony of a system i... |
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