{ "paper_id": "P87-1005", "header": { "generated_with": "S2ORC 1.0.0", "date_generated": "2023-01-19T09:13:30.724455Z" }, "title": "AN ENVIRONMENT FOR ACQUIRING SEMANTIC INFORMATION", "authors": [ { "first": "Damaris", "middle": [ "M" ], "last": "Ayuso", "suffix": "", "affiliation": { "laboratory": "", "institution": "BBN Laboratories Inc", "location": { "addrLine": "10 Moulton St", "postCode": "02238", "settlement": "Cambridge", "region": "MA" } }, "email": "" }, { "first": "Varda", "middle": [], "last": "Shaked", "suffix": "", "affiliation": { "laboratory": "", "institution": "BBN Laboratories Inc", "location": { "addrLine": "10 Moulton St", "postCode": "02238", "settlement": "Cambridge", "region": "MA" } }, "email": "" }, { "first": "Ralph", "middle": [ "M" ], "last": "Weischedel", "suffix": "", "affiliation": { "laboratory": "", "institution": "BBN Laboratories Inc", "location": { "addrLine": "10 Moulton St", "postCode": "02238", "settlement": "Cambridge", "region": "MA" } }, "email": "" } ], "year": "", "venue": null, "identifiers": {}, "abstract": "An improved version of IRACQ (for Interpretation Rule ACQuisition) is presented. I Our approach to semantic knowledge acquisition: 1) is in the context of a general purpose NL interface rather than one that accesses only databases, 2) employs a knowledge representation formalism with limited inferencing capabilities, 3) assumes a trained person but not an AI expert, and 4) provides a complete environment for not only acquiring semantic knowledge, but also maintaining and editing it in a consistent knowledge base. IRACQ is currently in use at the Naval Ocean Systems Center.", "pdf_parse": { "paper_id": "P87-1005", "_pdf_hash": "", "abstract": [ { "text": "An improved version of IRACQ (for Interpretation Rule ACQuisition) is presented. I Our approach to semantic knowledge acquisition: 1) is in the context of a general purpose NL interface rather than one that accesses only databases, 2) employs a knowledge representation formalism with limited inferencing capabilities, 3) assumes a trained person but not an AI expert, and 4) provides a complete environment for not only acquiring semantic knowledge, but also maintaining and editing it in a consistent knowledge base. IRACQ is currently in use at the Naval Ocean Systems Center.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Abstract", "sec_num": null } ], "body_text": [ { "text": "The existence of commercial natural language interfaces (NLI's), such as INTELLECT from Artificial Intelligence Corporation and Q&A from Symantec, shows that NLI technology provides utility as an interface to computer systems. The success of all NLI technology is predicated upon the availability of substantial knowledge bases containing information about the syntax and semantics of words, phrases, and idioms, as well as knowledge of the domain and of discourse context. A number of systems demonstrate a high degree of transportability, in the sense that software modules do not have to be changed when moving the technology to a new domain area; only the declarative, domain specific knowledge need be changed. However, creating the knowledge bases requires substantial effort, and therefore substantial cost. It is this assessment of the state of the art that causes us to conclude that know~edge acquisition is one of the most fundamenta/ prob/ems to widespread applicability of NLI techno/ogy. This paper describes our contribution to the acquisition of semantic knowledge as evidenced in IRACQ (for Interpretation Rule ACQuisition), within the context of our overall approach to representation of domain knowledge and its use in the IRUS natural language system [5, 6,271. An initial version of IRACQ was reported in [19] . Using IRACQ, mappings 1The work presented here was supported under DARPA contract #N00014-85-C-0016. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessenly representing the officual policies, either expressed or implied, of the Defense Advanced Research Projects Agency or of the United States Government. between valid English constructs and predicates of the domain may be defined by entering sample phrases.", "cite_spans": [ { "start": 1271, "end": 1281, "text": "[5, 6,271.", "ref_id": null }, { "start": 1326, "end": 1330, "text": "[19]", "ref_id": "BIBREF16" } ], "ref_spans": [], "eq_spans": [], "section": "Introduction", "sec_num": "1" }, { "text": "The mappings, or interpretation rules (IRules), may be defined for nouns, verbs, adjectives, and prepositions. IRules are used by the semantic interpreter in enforcing selectional restrictions and producing a logical form as the meaning representation of the input sentence.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Introduction", "sec_num": "1" }, { "text": "IRACQ makes extensive use of information present in a model of the domain, which is represented using NIKL [18, 21] , the terminological reasoning component of KL-TWO [26] . Information from the domain model is used in guiding the IRACQ/user interaction, assuring that acquisition and editing yield IRules consistent with the model. Further support exists for the IRule developer through a flexible editing and debugging environment. IRACQ has been in use by non-AI experts at the Naval Ocean Systems Center for the expansion of the database of semantic rules in use by IRUS. This paper first surveys the kinds of domain specific knowledge necessary for an NLI as well as approaches to their acquisition (section 2). Section 3 discusses dimensions in the design of a semantic acquisition facility, describing our approach. In section 4 we describe IRules and how they are used. An example of a clause IRule definition using IRACQ is presented. Section 5 describes initial work on an IRule paraphraser. Conclusions are in section 6.", "cite_spans": [ { "start": 107, "end": 111, "text": "[18,", "ref_id": "BIBREF15" }, { "start": 112, "end": 115, "text": "21]", "ref_id": "BIBREF18" }, { "start": 167, "end": 171, "text": "[26]", "ref_id": "BIBREF22" } ], "ref_spans": [], "eq_spans": [], "section": "Introduction", "sec_num": "1" }, { "text": "One kind of knowledge that must be acquired is lexical information. This includes morphological information, syntactic categories, complement structure (if any), and pointers to semantic information associated with individual words. Acquiring lexical information may proceed by prompting a user, as in TEAM [13] , IRUS [7] , and JANUS [9] . Alternatively, efforts are underway to acquire the information directly from on-line dictionaries [3, 16] .", "cite_spans": [ { "start": 307, "end": 311, "text": "[13]", "ref_id": "BIBREF11" }, { "start": 319, "end": 322, "text": "[7]", "ref_id": "BIBREF5" }, { "start": 335, "end": 338, "text": "[9]", "ref_id": "BIBREF7" }, { "start": 439, "end": 442, "text": "[3,", "ref_id": "BIBREF2" }, { "start": 443, "end": 446, "text": "16]", "ref_id": "BIBREF14" } ], "ref_spans": [], "eq_spans": [], "section": "Kinds of Knowledge", "sec_num": "2" }, { "text": "Semantic knowledge includes at least two kinds of information: selectional restrictions or case frame constraints which can serve as a filter on what makes sense semantically, and rules for translating the word senses present in an input into an underlying semantic representation. Acquiring such selectional restriction information has been studied in TEAM, the Linguistic String Parser [12] , and our system. Acquiring the meaning of the word senses has been studied by several individuals, including [11, 17] . This paper focuses on acquiring such semantic knowledge using IRACQ.", "cite_spans": [ { "start": 388, "end": 392, "text": "[12]", "ref_id": "BIBREF10" }, { "start": 503, "end": 507, "text": "[11,", "ref_id": "BIBREF9" }, { "start": 508, "end": 511, "text": "17]", "ref_id": null } ], "ref_spans": [], "eq_spans": [], "section": "Kinds of Knowledge", "sec_num": "2" }, { "text": "Basic facts about the domain must be acquired as well. This includes at least taxonomic information about the semantic categories in the domain and binary relationships holding between semantic categories. For instance, in the domain of Navy decision-making at a US Reet Command Center, such basic domain facts include:", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Kinds of Knowledge", "sec_num": "2" }, { "text": "All submarines are vessels.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Kinds of Knowledge", "sec_num": "2" }, { "text": "All vessels are units.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Kinds of Knowledge", "sec_num": "2" }, { "text": "Such information, though not linguistic in nature, is clearly necessary to understand natural language, since, for instance, \"Enterprise's overall rating\" presumes that there is such a readiness rating, which can be verified in the axioms mentioned above about the domain. However, this is cleady not a class of knowledge peculiar to language comprehension or generation, but is in fact essential in any intelligent system. General tools for acquiring such knowledge are emerging; we are employing KREME [1] for acquiring and maintaining the domain knowledge.", "cite_spans": [ { "start": 504, "end": 507, "text": "[1]", "ref_id": "BIBREF0" } ], "ref_spans": [], "eq_spans": [], "section": "All units are organizational entities. All vessels have a major weapon system. All units have an overall combat readiness rating.", "sec_num": null }, { "text": "Knowledge that relates the predicates in the domain to their representation and access in the underlying systems is certainly necessary. For instance, we may have the unary predicates vessel and harpoon.capable; nevertheless, the concept (i.e., unary predicate) corresponding to the logical expression ( X x) [vessel(x) & harpoon.capable(x)] may correspond to the existence of a \"y* in the \"harp* field of the \"uchar\" relation of a data base. TEAM allows for acquisition of this mapping by building predicates \"bottom-up\" starting from database fields. We know of no general acquisition approach that will work with different kinds of underlying systems (not just databases). However, maintaining a distinction between the concepts of the domain, as the user would think of those concepts, separate from the organization of the database structure or of some other underlying system, is a key characteristic of the design and transportability of IRUS.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "All units are organizational entities. All vessels have a major weapon system. All units have an overall combat readiness rating.", "sec_num": null }, { "text": "Finally, a fifth kind of knowledge is a set of domain plans. Though no extensive set of such plans has been developed yet, there is growing agreement that such a library of plans is critical for understanding narrative [20] , a user's needs [22] , ellipsis [8, 2] . and ill-formed input [28] , as well as for following the structure of discourse [14, 15] . Tools for acquiring a large collection of domain plans from a domain expert, rather than an AI expert, have not yet appeared. However, inferring plans from textual examples is under way [17].", "cite_spans": [ { "start": 219, "end": 223, "text": "[20]", "ref_id": "BIBREF17" }, { "start": 241, "end": 245, "text": "[22]", "ref_id": null }, { "start": 257, "end": 260, "text": "[8,", "ref_id": "BIBREF6" }, { "start": 261, "end": 263, "text": "2]", "ref_id": "BIBREF1" }, { "start": 287, "end": 291, "text": "[28]", "ref_id": "BIBREF24" }, { "start": 346, "end": 350, "text": "[14,", "ref_id": "BIBREF12" }, { "start": 351, "end": 354, "text": "15]", "ref_id": "BIBREF13" } ], "ref_spans": [], "eq_spans": [], "section": "All units are organizational entities. All vessels have a major weapon system. All units have an overall combat readiness rating.", "sec_num": null }, { "text": "We discuss in this section several dimensions available in designing a tool for acquiring semantic knowledge within the overall context of an NLI. In presenting a partial description of the space of possible semantic acquisition tools, we describe where our work and the work of several other significant, recently reported systems fall in that space of possibilities.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Knowledge", "sec_num": null }, { "text": "One could design tools for a specific subclass of underlying systems, such as database management systems, as in TEAM [13] and TELl [4] . The special nature of the class of underlying systems may allow for a more tailored acquisition environment, by having special-purpose, stereotypical sequences of questions for the user, and more powerful special-purpose inferences. For example, in order to acquire the variety of lexical items that can refer to a symbolic field in a database (such as one stating whether a mountain is a volcano), TEAM asks a series of questions, such as \"Adjectives referencing the positive value?\" (e.g., volcanic), and \"Abstract nouns referencing the positive value?\" (e.g., volcano). The fact that the field is binary allows for few and specific questions to be asked.", "cite_spans": [ { "start": 118, "end": 122, "text": "[13]", "ref_id": "BIBREF11" }, { "start": 132, "end": 135, "text": "[4]", "ref_id": null } ], "ref_spans": [], "eq_spans": [], "section": "Class of underlying systems.", "sec_num": "3.1" }, { "text": "The design of IRACQ is intended to be general purpose so that any underlying system, whether a data base, an expert system, a planning system, etc., is a possibility for the NLI. This is achieved by having a level of representation for the concepts, actions, and capabilities of the domain, the domain model, separate from the model of the entities in the underlying system. The meaning representation for an input, a logical form, is given in terms of predicates which correspond to domain model concepts and roles (and are hence referred to as domain mode/ predicates). IRules define the mappings from English to these domain model predicates. In our NLI, a separate component then translates from the meaning representation to the specific representation of the underlying system [24, 25] . IRACQ has been used to acquire semantic knowledge for access to both a relational database management system and an ad hoc application system for drawing maps, providing calculations, and preparing summaries; both systems may be accessed from the NLI without the user being particularly aware that there are two systems rather than one underneath the NLI.", "cite_spans": [ { "start": 783, "end": 787, "text": "[24,", "ref_id": "BIBREF20" }, { "start": 788, "end": 791, "text": "25]", "ref_id": "BIBREF21" } ], "ref_spans": [], "eq_spans": [], "section": "Class of underlying systems.", "sec_num": "3.1" }, { "text": "Another dimension in the design of a semantic knowledge acquisition tool is the style of the underlying semantic representation for natural language input. One could postulate a unique predicate for almost every word sense of the language. TEAM seems to represent this approach. At some later level of processing than the initial semantic acquisition, a level of inference or question/answering must be provided so that the commonalities of very similar word senses are captured and appropriate inferences made. A second approach seems to be represented in TELl, where the meaning of a word sense is translated into a boolean composition of more primitive predicates. IRACQ represents a related approach, but we allow a many-to-one mapping between word senses and predicates of the domain, and use a more constraining representation for the meaning of word senses. Following the analysis of Davidson [10] we represent the meaning of events (and also of states of affairs) as a conjunction of a single unary predicate and arbitrarily many binary predicates. Objects are represented by unary predicates and are related through binary relations. Using such a representation limits the kind and numbers of questions that have to be asked of the user by the semantic acquisition component. The representation dovetails well with using NIKL [18, 21] , a taxonomic knowledge representation system with a formal semantics, for stating axioms about the domain.", "cite_spans": [ { "start": 900, "end": 904, "text": "[10]", "ref_id": "BIBREF8" }, { "start": 1335, "end": 1339, "text": "[18,", "ref_id": "BIBREF15" }, { "start": 1340, "end": 1343, "text": "21]", "ref_id": "BIBREF18" } ], "ref_spans": [], "eq_spans": [], "section": "Meaning representation.", "sec_num": "3.2" }, { "text": "One may choose to have an explicit, separate representation for concepts of the domain, along with axioms relating them. Both IRUS and TEAM have explicit models. Such a representation may be useful to several components of a system needing to do some reasoning about the domain. The availability of such information is a dimension in the design of semantic acquisition systems, since domain knowledge can streamline the acquisition process. For example, knowing what relations are allowable between concepts in the domain, aids in determing what predicates can hold between concepts mentioned in an English expression, and therefore, what are valid semantic mappings (IRules, in our case).", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Model of the domain", "sec_num": "3.3" }, { "text": "Our NIKL representation of the domain knowledge, the domain model, forms the semantic backbone of our system. Meaning is represented in terms of domain model predicates; its hierarchy is used for enforcing selectional restrictions and for IRule inheritance; and some limited inferencing is done based on the model. After semantic interpretation is complete, the NIKL classification algorithm is used in simplifying and transforming high level meaning expressions to obtain the underlying systems' commands [25] . Due to its importance, the domain model is developed carefully in consultation with domain experts, using tools to assure its correctness. This approach of developing a domain model independently of linguistic considerations or of the type of underlying system is to be distinguished from other approaches where the domain knowledge is shaped mostly as a side effect of other processes such as lexical acquisition or database field specification.", "cite_spans": [ { "start": 506, "end": 510, "text": "[25]", "ref_id": "BIBREF21" } ], "ref_spans": [], "eq_spans": [], "section": "Model of the domain", "sec_num": "3.3" }, { "text": "3.4 Assumptions about the user of the acquisition tool. If one assumes a human in the semantic acquisition process, as opposed to an automatic approach, then expectations regarding the training and background of that user are yet another dimension in the space of possible designs. The acquisition component of TELl is designed for users with minimal training. In TEAM, database administrators or those capable of designing and structuring their own database use the acquisition tools. Our approach has been to assume that the user of the acquisition tool is sophisticated enough to be a member of the support staff of the underlying system(s) involved, and is familiar with the way the domain is conceived by the end users of the NLI. More particularly, we assume that the individual can become comfortable with logic so that he/she may recognize the correctness of logical expressions output by the semantic interpreter, but need not be trained in AI techniques. A total environment is provided for that class of user so that the necessary knowledge may be acquired, maintained, and updated over the life cycle of the NLI. We have trained such a class of users at the Naval Ocean Systems Center (NOSC) who have been using the acquisition tools for approximately a year and a half.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Model of the domain", "sec_num": "3.3" }, { "text": "It would appear that most acquisition systems have focused on the inference problem of acquiring knowledge initially and have paid relatively little attention to explaining to the user what knowledge has been acquired, providing sophisticated editing facilities above the level of the internal data structures themselves, or providing consistency checks on the database of knowledge acquired. Providing such a complete facility is a goal of our effort; feedback from non-AI staff using the tool has already yielded significant direction along those lines. The tool currently has a very sophisticated, flexible debugging environment for testing the semantic knowledge acquired independently of the other components of the NLI, can present the knowledge acquired in tables, and uses the set of domain facts as a way of checking the consistency of what the user has proposed and suggesting alternatives that are consistent with what the system already knows. Work is also underway on an intelligent editing tool guaranteeing consistency with the model when editing, and on an English paraphraser to express the content of a semantic rule.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "Scope of utilities provided.", "sec_num": "3.5" }, { "text": "The original version of IRACQ was conceived by R. Bobrow and developed by M. Moser [19] . From sample noun phrases or clauses supplied by the user, it inferred possible selectional restrictions and let the user choose the correct one. The user then had to supply the predicates that should be used in the interpretation of the sample phrase, for inclusion in the IRule.", "cite_spans": [ { "start": 83, "end": 87, "text": "[19]", "ref_id": "BIBREF16" } ], "ref_spans": [], "eq_spans": [], "section": "IRACQ", "sec_num": "4" }, { "text": "From that original foundation, as IRUS evolved to use NIKL. IRACQ was modified to take advantage of the NIKL knowledge representation language and the form we have adopted for representing events and states of affairs. For example, now IRACQ is able to suggest to the user the predicates to be used in the interpretation, assuring consistency with the model. Following a more compositional approach, IRules can now be defined for prepositional phrases and adjectives that have a meaning of their own, as opposed to just appearing in noun IRules as modifiers of the head noun. Thus possible modifiers of a head noun (or nominal semantic class) include its complements (if any), and only prepositional phrases or other modifiers that do not have an independent meaning (as in the case of idioms). Analogously, modifiers of a head verb (or event class) include its complements. Adjective and prepositional phrase IRules specify the semantic class of the nouns they can modify.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRACQ", "sec_num": "4" }, { "text": "Also, maintenance facilities were added, as discussed in sections 4.3, 4.4, and 5.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRACQ", "sec_num": "4" }, { "text": "An IRule defines, for a particular word or (semantic) class of words, the semantically acceptable English phrases that can occur having that word as head of the phrase, and in addition defines the semantic interpretation of an accepted phrase. Since semantic processing is integrated with syntactic processing in IRUS, the IRules serve to block a semantically anomalous phrase as soon as it is proposed by the parser. Thus, selectional restrictions (or case frame constraints) are continuously applied. However, the semantic representation of a phrase is constructed only when the phrase is believed complete.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRules", "sec_num": "4.1" }, { "text": "There are IRules for four kinds of heads: verbs, nouns, adjectives, and prepositions. The left hand side of the. IRule states the selectional restrictions on the modifiers of the head. The right hand side specifies the predicates that should be used in constructing a logical form corresponding to the phrase which fired the IRule.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRules", "sec_num": "4.1" }, { "text": "When a head word of a phrase is proposed by the parser to the semantic interpreter, all IRules that can apply to the head word for the given phrase type are gathered as follows: for each semantic property that is associated with the word, the IRules associated with the given domain model term are retrieved, along with any inherited IRules. A word can also have IRules fired directly by it, without involving the model. Since the IRules corresponding to the different word senses may give rise to separate interpretations, they are carried along in parallel as the processing continues. If no IRules are retrieved, the interpreter rejects the word.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRules", "sec_num": "4.1" }, { "text": "One use of the domain model is that of IRule inheritance. When an IRule is defined, the user decides whether the new IRule (the base IRule) should inherit from IRules attached to higher domain model terms (the inherited IRules), or possibly inherit from other IRules specified by the user. When a modifier of a head word gets transmitted and no pattern for it exists in a base IRule for the head word, higher IRules are searched for the pattern. If a pattern does exist for the modifier in a given IRule, no higher ones are tried even if it does not pass the semantic test. That is, inheritance does not relax semantic constraints.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "IRules", "sec_num": "4.1" }, { "text": "In this section we step through the definition of a clause IRule for the word \"send *, and assume that lexical information about \"send ~ has already been entered. The sense of \"sending\" we will define, when used as the main verb of a clause, specifies an event type whose representation is as follows:", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "An IRACQ session", "sec_num": "4.2" }, { "text": "( Z x) [deployment(x) & agent(x, a) & object(x, o) & destination(x, d)],", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "An IRACQ session", "sec_num": "4.2" }, { "text": "where the agent a must be a commanding officer, the object o must be a unit and the destination d must be a region.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "An IRACQ session", "sec_num": "4.2" }, { "text": "From the example clauses presented by the t~ser IRACQ must learn which unary and binary predicate:. are to be used to obtain the representation above Furthermore, IRACQ must acquire the most geP.e'~ semantic class to which the variables a, o, and d ,~,=~ belong.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "An IRACQ session", "sec_num": "4.2" }, { "text": "Output from the system is shown in bold face input from the user in regular face, and comments at,.. inserted in italics.", "cite_spans": [], "ref_spans": [], "eq_spans": [], "section": "An IRACQ session", "sec_num": "4.2" }, { "text": "Word that should trigger this IRule: send Domain model term to connect IRule to (select-K to view the network): deployment This concludes our sample IRACQ session." }, "TABREF0": { "content": "
a picture of<B: If the user did not specify the concept
the network around DEPLOYMENT.>DEPLOYMENT (or some other concept) at
point A above as the central concept in this
lew ConceptNew Hoh Edit Robsense of \"sending', then IRACQ would compute those unary concepts c such that
there are binary predicates relating c to
eachcase'sconstraint,e.g.,to
u~COMMANDING.OFFICER, REGION, and UNIT. The user would be presented with a
menu of such concepts c. IRACQ would
now proceed in the same way for A or B.>
<IRACQ then looks in the NIKL domain
model for binary predicates relating the
event class (e.g., DEPLOYMENT) to one of
the cases' semantic class (e.g. REGION),
and presents the user with a menu of those
binary predicates (figure 3). Mouse options
allow the user to retrieve an explanation of
how a predicate was found, or to look at the
Figure 1: Network centered on DEPLOYMENTnetwork around it. DESTINA T/ON.OF.>The user picks
Enter an example sentence using \"send\": An admiral sent Enterprise to the Indian Ocean.Which of the following predicates should relate DEPLOYMENT to REGION in the MRL?:
LOCATION.OF
<IRACQ uses the furl power of the IRUSDESTINATION.OF
parser and interpreter to interpret this sen-tence. A temporary IRule for \"send\" is used which accepts any modifier (it is assumedFigure 3: and REGION Relations between DEPLOYMENT
that the other words in the sentence can
aJready be understood by the system.)<IRACQ presents a menu of binary predi.
IRACQ recognizes that an admiral is of thecatasrelatingDEPLOYMENTand
type COMMANDING.OFFICER, and dis-COMMANDING.OFFICER, and one relating
plays a menu of the ancestors ofDEPLOYMENT and UNIT. The user picks
COMMANDING.OFFICER in the NIKLAGENT and OBJECT, raspective/y.>
taxonomy (figure 2).>
Choose a generalization for
COMMANDING.OFFICER<The user may provide more examples.
COMMANDING.OFFICER PERSON CONSCIOUS.BEINGRedundant information would be recognized automatically.> Should this IRule inherit from higher IRules? yes
ACTIVE.ENTITY
OBJECT THING<A popup window allowing the user to enter comments appears. The default com-
Figure 2: Generalizations ofment has the creation date and the user's
COMMANDING.OFFICERname.>
<The user's selection specifies the case
frame constraint on the logical subject of \"send'. The user picks COMMANDING.OFFICER. IRACQ will per-form similar inferences and present a menuhead * object (is-a UNIT) pp ((pp)
for the other cases in the example phrase
as well, asking each time whether the
modifier is required or optional Assume
that the user selects UNIT as the logical
object and REGION as the object of the
preposition \"to\".>
", "num": null, "html": null, "text": "", "type_str": "table" } } } }