CA2090883C - Apparatus and methods for providing design advice - Google Patents

Abstract

A knowledge-based artificial intelligence system which provides design advice. The artificial intelligence system includes a knowledge base of design information.
Users of the system indicate an area about which they require design advice. Thesystem provides the relevant advice. Included in the advice is an indication of the "owner" of the advice. The advice and the relationship between the design made by the user are part of a trace of the users' session with the system. The trace becomes pan of a design document for the design. When the design is reviewed, the trace is reviewed as well. The system includes an interface for updating the knowledge base, and if the design review indicates a need to correct the knowledge base, the corrections are made using the interface for updating. A preferred embodiment of the system is used to provide advice to designers of a large software system concerning the use of an error reporting and handling system in the system beingdesigned.

Description

209088~

~pparatus and Methods for Providing Design Advice Background of the Inven~on Field of the Invention This invention relates to information systems that produce advice about a design5 domain in order to help someQne de-cigning in the dom~in Such systems produce advice by using a "knowledge base" in which information ,~lc~ to dçsi~ning in the domain is stored. Typical domains include the design of software, integratedcircuits, mech~nir~l devices, and buil~in&~c Description of the PriorArt Knowledge-based technology is central to the field of Artificial Intelligence and various application areas that evolved from it (Readings in Knowledge Representation, edited by Ronald J. Brachman and Hector J.
Levesque, Morgan-R~l~ffm~nn 1985). This te~hnQlogy has three facet~s. First are techni~lues for rep~senting knowledge about the domain (such as configuring 15 co."l.uter components) in a co.,ll,u~r. Issues of succinctness and completeness arise in the ~p.e~ent~tion of domain knowledge. The second &cet is access, techniques for presenting and making accescible approp,iate knowledge at app,.,l"iate times. The third facet can be called update, mainten~nce~ or evolution;
it involves the ability to change the knowledge in response to new or unanticipated 20 conditions in the domain. Note that how the knowledge is ,~p~sellted can greatly impact the second and third facets of knowledge-based t~hnology.
An i"~ t~lt appli~ tion area for knowledge-based technology is the area of dcsign (Report on DARPA-Sponsored Workshop on Design, edited by Saul Amarel, Terhnic~l Report no. LCSR-TR-160, Department of Computer Science, 25 Rutgers U~ ersity, April, 1991). Design is an important eng;.~ g activity where objects and artifacts are either decig~d from scratch or modified (re-design); these objects and artifacts can be physical objects (integrated circuits, bridges), non-physical objects (software, soîl~ale systems), or even processes (for chemical en&i~ g, man~f~ ing). The process of design usually involves or results in 30 e~tern~l ~p~sent~tions of the objects and artifacts, such as blueprints, scale models, or block diagrams. Design is very knowledge-intensive: it requires knowledge of the engineering domain, relevant problem-solving knowledge.

22o90~83 common sense knowledge, and knowledge of the tools and techniques for external representation. It is very often the case that a large part of the required body of knowledge is only available in the heads of experts in the area and is not written down in any comprehensive fashion. This makes it difficult for novices in the area, 5 or experts unfamili~r with a sub-domain, to locate, understand, and apply design knowledge relevant to a particular design situation.
New technology has resulted in automation of some parts of engineering design, in particular, computer-based graphics workstations for accessing and manipulating the artifacts of design. However, very little work has 10 been done in actually a~icting the design process by providing access to design knowledge. Such knowledge remains as org~ni7~tional "folklore", or ~p.~sen~d in voluminous documents which only provide a primitive indexing ability. An alternative approach, the subject of this patent, is to codify design knowledge in a knowledge base and, equally important, provide mPch~nicms for a user to access 15 that knowledge at relevant portions of the design process and provide mech~nicm~
for the m~inten~nre of the knowledge in the knowledge base.
~ csllming the viability of such an approach, a number of important benefits will result. First of all, the availability of appropriate design knowledge will improve the design process and produce superior designs. Second, the 20 codification of design knowledge will allow that knowledge to be efficiently dicsemin~tPd and re-used, again improving the overall design process within an org~ni7~tion. Third, if a mP~h~nicm of updating the design knowledge, also called knowledge m~ n~nce~ can be integrated in an org~ni7~tion~ this knowledge will remain culTent and relevant as design citn~tionC change.
This latter issue of knowledge m~inten~nce is particularly critical in design. Unlike me-lir~ gnocic or computer configuration dom~inc, the body of relevant design knowledge is both harder to "get right" initially and will change because of changing engineering standards and practices and organizational changes. In addition, the çnginpering design process is often a process of re-design of exicting design objects, and thus is very dependent on the ch~nging state of those objects. This further increases the importance of knowledge m~intPn~nce One recent org~ni7~tiQnal development that can ease the m~inten~nce problem is the so-called "quality revolution" in commerce and industry. This ~n 9 ~8-83 ~1 movement emphasizes a variety of org~ni7~tional changes resulting in the notion of an org~ni7~tionalprocess. Each organi7~tional process can be viewed as discreet unit with a number of inputs (customer requests), outputs (organizational products), and various feedback loops which can be used to evaluate the effectiveness of the process. A process S can be further divided, in a hierarchical fashion, into sub-processes. One of the many benefits of this viewpoint is that a process or sub-process can have an owner designated, providing a single point of contact for evaluating and modifying the process. The idea of organi7~tional process can be used to address the problem of maintenance of a design knowledge base if the maintenance problem can be integrated into a new or existing 10 organizational process.

Summary of the Invention The above object is achieved by apparatus for producing advice about a design and for annotating designs with the advice produced. Advice is information about the design domain relevant and useful to the design.

In accordance with one aspect of the present invention there is provided appaldl~ls for providing advice about a design, the apparatus comprising: a design document; a knowledge base from which information about a domain relevant to thedesign is obtainable in response to a query; and design assistant means for providing an annotation including the advice for the design document, the design assistant means 20 including query providing means for producing the query in response to a specification of an advice area received from a user and providing the query to the design assistant means for execution on the knowledge base and advice providing means responsive to the information produced in response to the execution of the query for employing the information to provide the annotation.

It is an object of the invention to provide designers with improved access to information.

It is a further object of the invention to support the ongoing evolution of the information in the knowledge base, as new knowledge is generated and as the - information already in the knowledge base is found inadequate.

I

209~883 It is an additional object of the invention to suppon and focus ~ommunication among design~rs, both decreasing the need for communication, and, when cornmuni~tion still is required, ensuring that it occurs directly between a d~signer who needs help and a de.cign~.r who can give the help.
s These and other objects and advantages of the invention will be al-parent to those of ordinary skill in the art after perusing the Detailed l~x~ ;ption and Drawing, wherein:

Brief Description of the Drawing Figure 1 illustrates the overall structure of the invention; it includes 1(~ thc principal components of each of the mech~ni.cm.c in the embodiment and how he mech~ni.cm.c are employed in the design process;
Figure 2 illustrates the ~LI u~ of the knowledge base in a p.efel.ed embodimpnt Figures 3 and 4 illustrate two methods of interacting with a designer to obtain input required to access relevant information in the knowledge base;
Figure S illustrates the process of computing advice in a preferred embo~liment; and Figure 6 illustrates a partial trace of an int~.~;lion with an application of the app~alus and methods applied to the domain of software design.

Detailed Description The following Detailed Description begins with an overview of the invention and then proceeds to a det~iled description of a preferred embodiment thereof.

Overview of the Invention: Figure 1 Figure 1 shows an artificial intelligence system 102 embedded in a larger design process 101. The artificial intelligence system includes a knowledge base of design information and is implemented using the present invention. The major components are the following:

2o~0883 ~ Design Knowledge Base (DKB) 104 contains the information about decigning in a particular domain used to produce design advice;
~ Design Assistant 103 is a computer program that interacts with a design~r to give the decign~r access to relevant information from DKB
104. Design ~ccict~nt 103 consists of two parts, a Query Provider QP
and an Advice Provider AP.
. ~;..ten~n.~e ,~ccict~nt 105 is a computer program that interacts with a knowledge base m~int~in~r to add new information to DKB 104;
~ The Annotated Design Document 106 consists of three parts:
~ Design 107 - a specification of the product to be built;
~ Trace of inlel~lions with the Design ~csict~nt 108 - shows the advice given by Design Assistant 103, in particular, the features of the Design 107 due to advice produced from DKB
104;
~ Suggested updates to Design Knowledge Base 109 -information that a clecign~:r believes should be added to DKB
104.
The operation of system 102 within the org~ni7~tional process 101 is as follows. While constructing a Design 107, a decign~r interacts with the Query Provider QP part of Design .Accict~nt 103 by providing user input UI 117. On thebasis of this intG,a.,lion, Design Accict~nt 103 queries DKB 104 with Query 119 to access design information relevant to the decigner. The DKB 104 provides Design Information DI 123 to the Design Assict~ntlO3. The Advice Provider AP part of the Design .Acsict~nt pl~l~ the relevant information as Design Advice DA 121 to the dçsig~r as advice. Each item in the advice is labeled with the "owner" of the advice. This advice b~collles an annotation 108 to the Annotated Design Document106. In addition, de-cigners may suggest additions to or modi~lcations of DKB 104 where they believe it to be incomplete or incorrect. These suggestions 109 also becorne part of the Annotated Design Document 106.
The Annotated Design Document 106 is then subject to a Review 111. The Review 111 is a meeting in which a group of experienced designers in the relevant domain examine the Annotated Design Document 106 to look for problems with the design. The presence of the trace of design advice 108 and suggested updates to the knowledge base 109 is crucial in supporting the evolution of DKB 104. The trace 108 makes problems in the design due to advice based on incorrect information in DKB 104 apparent. The suggested updates 109 also are 2~90~3 judged to see if they are concictent with the reviewers' knowledge and may be extended or modified based on the reviewers' exqminqtion of the Annotated DesignDocument 106.
After the Review 111, the Annotated Design Document 106 is given 5 to a human knowledge base mqintqiner The process of KB Maintenqnce 112 involves the knowledge base mqintqiner interacting with a 1~5qintenqnce ~cc;ctq-nt program 105 to update DKB 104 based on the mo~ificqtions and additions discovered to be n~esc~ during Design 110 and Review 111 and ,~cG, ied on the Annotated Design Document 106. For each update of the knowledge base, the 10 person who suggested that update (the "owner") is associated with the new item in the knowledge base.

Detailed Description of the Structure and Operation of the Invention We first describe the org~ni7~tion of information in the Design Knowledge Base (DKB) 104. The DKB 104 must contain information that is 15 relevant to the task of designing in a particular domain. The combination of the org~ni7~tion of information in DKB 104 and the working of the Design Assistant 103 must allow de.cignPr.c easy access to relevant design inform~tiQn In a plerelled embodiment, the DKB 104 contains the following major components (see Figure 2):
20 ~ A hierarchy of Design Descriptions 201; in the area of software design, for ey~mple~ Design Descriptions might include "Designs that consume too many resources" and "Designs that send too many m~S~ges"; the second Description would be a specialization of the first;
~ A set of Design Decisions 202, indeYed by Design Description; in the area of software design, for example, a Design Description might be "Should I define a new process or use an existing process?"; and ~ A set of Advice Items 203, index~d by Design Description and Design Decision.
The m~ning of these components is as follows:
IF a Description DesC~ is determined to be true of a design D, AND DesCr indexes the Decisions Dl,...,DN, 2 0 ~ 3 AND each <DeSCr ~ Di> pair (1 < i < N) indexes the Advice Items Ai, ...Ai~M
THEN the advice items Al,l,...,A~,M,...,AN,l,...,AN,M are relevant to the design D.
S There are three additional aspects to the representation of design infonn~tion-~ Advice items are labeled as eitherprimary or secondary;
~ Advice items may be labeled as overrid~ng; and ~ Design Descriptions have an associated establishing question.
The use of this information is discussed below.
In a pn_r~lncd embodiment, we use CLASSIC (L.A. Resnick, 'Y'he CLASSIC User's Manual", AT&TBell Laboratories Technical Report, 1991; R.J.
Brachman, A. Borgida, D.L. McGuinness, P.F. Patel-Schneider, and L.A.
Resnick, "Living with Classic: How and When to Use a KL-One-like Language", in J.Sowa, ed., Principles of Semantic Networks: Explorations in the Representation of Knowledge; Morgan-R~Ilffm~nn, 1991, pp. 401-456.) as the language for replesPI~ting the design inforrnation described above. The abstract, pictorial presentations of design inforrnation shown in Figure 2 are realized inCLASSIC as follows:
~ each Design Description 201 is a CLASSIC concept; the CLASSIC
rel~tionshirs parent and child are used to represent the hit;l~ hy;
~ each Design Decision 202 also is a CLASSIC concept;
~ each Advice Item 203 is a CLASSIC individual;
~ the index relationships among Design Descriptions, Design Decisions, and Advice Items are represented by CLASSIC roles, which simply are a means for stating a rel~tionshir) between two objects; and ~ roles also are used to represent the additional features of the representation identified above: primary vs. secondary, overriding, and establishing questions.
Figure 2 also contains an example showing more precisely how Design Desclil)tions 201, Design Decisions 202, and Advice Items 203 are related.
In the example, the nodes in the tree 205 in~lir~tp Design Descriptions 207, ovals 209 intlir~te Design Decisions, and text of the form "A-~' 211 in~1icatps an Advice 2n~0883 Item. The indexing relationship is shown informally, by the position of Descriptions, Decisions, and Advice Items. Relationships shown in the example include ~ Descr-1 indexes Decision 1;

~ <Descr-1, Decision 1> indexesA-1;

~ Descr-6 indexes Decision 3; and ~ <Descr-6, Decision 3> indexes A-15 and A-16.

We next discuss the interaction of the Design Assistant 103 with a designer, illustrating ~ how the interaction gives the Design Assistant 103 sufficient information to access relevant information in the Design Knowledge Base 104; and ~ how the Design Assistant 103 computes advice based on the interaction with the designer.

The goal of the interaction is to get the designer to classify his or her designunder the most specific relevant Design Description; this results in the most specific possible advice. We describe two preferred embodiments for engaging n such an interaction with the designer. The first embodiment, given in FIG. 3, is preferable for very small description hierarchies; the second embodiment, given in FIG. 4, is preferable for all larger hierarchies. We call the algorithm GET-DESIGNER-TO-CLASSIFY-DESIGN. Note that the hierarchical representation of Design Descriptions allows for an economical representation of advice; advice common to a number of Descriptions can be represented at a common parent Description. Exceptions to this general advice can be labeled as being overriding. Overriding advice cancels out or overrides more general advice and replaces the general advice when the advice is presented. For example, in FIG. 2, Advice Item A-13 overrides Advice Item A-9, and Advice Item A-18 overrides Advice Item A-12. If Description Desc-6 is found to be relevant, Advice Item A-13 would be presented to the user and Advice Item A-9, which relates to the save Design Decision, would not be presented. Likewise, if Description D7 was found to be relevant, Advice Item A-18 would be presented to the user and Advice Item A-12 would not be.

9 ~ 3 After obtaining this information from the designer, the Design A.ssistant 103, uses algorithm COMPUTE-ADVICE (shown in Figure 5) to compute the advice that is relevant to the design being constructed. In addition to rres~nting the advice to the designer, the Design Assistant also produces a trace of th~ advisory interaction, including the advice produced. This trace 108 then ~comes part of the Annotated Design Docl-m~nt 106.
The Annotated Design Document 106 then is e~mine~ in the Review 111. In particular, the parts of the design due to the advice gel~.ated from the DKB 104 will be e~mined Any modifications of or additions to the 1() information in the DKB 104 detected during the Design 110 and Review 111 processes will be ex~mined by a knowledge base m~int~in~r. During the process ofKB Maintenance 112, the knowledge base m~int~iner will use the l~in~en~nce ci.~t~nt program 105 to integrate these modifications and additions into the DKB
I ()4.

15 Application of the Techniques to Software Design The described apparatus and methods for providing design advice have been applied to the domain of software design. The specific domain is the use and a particular error reporting and h~n~ling mech~nicm that is used in a software program.
A hierarchy of design descriptions relevant to this error reporting mechanism has been l~,?resented in a knowledge base. A set of design decisions relevant to the above mentioned error mechanism have been represented and indexed by design desc~ ion. Finally, a set of advice items relevant to the use of the error mechanism has been represented and indexed by design description and design decision. These advice items are labelled as either primary or secondary;some are labelled as overridrng; and owners of the advice items are stored.
A design assistant was created which uses the algorithm shown in figure 3 to obtain information from the designer. The design ~ccict~nt then uses the algorithm shown in figure 5 to compute the advice relevant to the design being constructed. The advice is presented to the designer and a trace of the interaction of the designer with the design assistant is produced. This trace becomes part of the design document as described in this application. Figure 6 illustrates a Partial Trace lo ~ 3 601 of this system. DKT problem question 603 is presented to the user. If the user response is "yes", then Design Advice 605 is presented to the user, consisting of Primary Advice 607 and secondary advice 609.

Conclusion The foregoing Detailed Description has disclosed to those skilled in the arts towhich the invention pertains how one may make and use a system for delivering design advice and evolving the knowledge base from which the advice is generated. Othertechniques that those disclosed herein for practicing the invention and other areas in which the invention may be applied will be apparent to those skilled in the artsconcerned after reading the foregoing disclosure. For example, CLASSIC could be replaced by other representation languages.

In addition, while the interaction of the Design Assistant and the designer described here is based on the Design Assistant asking a question, getting the designer's answer, then acting on the basis of the answer, other methods of interaction would be even more appropriate in other circumstances. For example, if the Design being produced is a formal object, the Design Assistant could apply rules of inference directly to the design in order to classify it, rather than querying the designer. Further, advice could be delivered in many different ways, for example, combinations of text, graphics, video, etc.

Because of the wealth of the possible embodiments of the invention, the foregoing Detailed Description is to be understood as being in every respect illustrate and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the Detailed Specification, but rather from the claims as interpreted in light of the Detailed Description and in accordance with the doctrine of equivalences.

.

Claims (9)

1. Apparatus for providing advice about a design, the apparatus comprising:
a design document;
a knowledge base from which information about a domain relevant to the design is obtainable in response to a query; and design assistant means for providing an annotation including the advice for the design document, the design assistant means including query providing means for producing the query in response to a specification of an advice area received from a user and providing the query to the design assistant means for execution on the knowledge base and advice providing means responsive to the information produced in response to the execution of the query for employing the information to provide the annotation.

2. The apparatus set forth in claim 1 wherein:
the information has an owner, and the annotation includes data indicating the owner of the information employed in providing the advice.

3. The apparatus set forth in claim 1 wherein:
the advice providing means further includes means for permitting the user to indicate that the user has not accepted the advice; and the advice providing means further includes an indication that the user has not accepted the advice in the annotation.

4. The apparatus set forth in claim 1 further comprising:
means for updating the knowledge base with additional information based on a review of the annotation by a party interested in the design.

5. The apparatus set forth in claim 1 wherein:
the knowledge base includes a hierarchy of design descriptions, a set of design decisions indexed by design descriptions, and a set of advice items indexed by design decision and design description;
and the design assistant means executes the query by locating a design description corresponding to the advice area, locating a design decision indexed by the design description, locating an advice item indexed by the located design description and the located design decision, and obtaining the located advice item.

6. The apparatus set forth in claim 5 wherein:
at least one of the design descriptions has an establishing question associated therewith; and the query providing means provides the establishing question to the user;
and the user provides the specification of the advice area by providing an answer tothe establishing question to the query providing means.

7. The apparatus set forth in claim 5 wherein:
the advice items include an overriding advice item; and when the design assistant means locates both an overriding advice item and another advice item which is not an overriding advice item, in executing the query, the design assistant means responds to the overriding advice item by obtaining the overriding advice item as the located advice item.

8. The apparatus set forth in claim 7 wherein:
the apparatus further includes means for updating the knowledge base; and the means for updating the knowledge base updates the knowledge base with additional information based on a review of the annotation which includes an indication of whether an advice item is overriding.

9. The apparatus set forth in claim 5 wherein:
the advice items include primary advice items and secondary advice items and the knowledge base further includes labels which indicate whether a located advice item is a primary advice item or a secondary advice item;
and the advice providing means responds to a label by indicating whether the provided advice is primary or secondary advice.