• Land and Housing Review
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• v.1 no.1
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• pp.1-7
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• 2010

Case-based reasoning (CBR) method can make estimators understand the estimation process more clearly. Thus, CBR is widely used as a methodology for cost estimation. In CBR, the quality of case retrieval affects the relevance of retrieved cases and hence the overall quality of the reminding capability of CBR system. Thus, it is essential to retrieve relevant past cases for establishing a robust CBR system. Case retrieval needs the following tasks to obtain appropriate case(s); indexing, search, and matching (Aamodt and Plaza 1994). However, the previous CBR researches mostly deal with matching process that has limits such as accuracy and efficiency of case retrieval. In order to address this issue, this research presents a CBR cost model for building projects that has two-step retrieval process: decision tree and nearest neighbor methods. Specifically, the proposed cost model has indexing, search and matching modules. Features in the model are divided into shape-based and scale-based attributes. Based on these, decision tree is established for facilitating the search task and nearest neighbor method was utilized for matching task. In regard to applying nearest neighbor method, attribute weights are assigned using GA optimization and similarity is calculated using the principle of distance measuring. Thereafter, the proposed CBR cost model is developed using 174 cases and validated using 12 test cases.

• Journal of KIISE
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• v.42 no.11
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• pp.1339-1348
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• 2015

In a distributed system environment based on a service-oriented architecture, separate systems collaborate to achieve the goals of the entire system by using services provided other systems. A service quality violation from using one service can cause runtime system failure in the environment. The existing self-adaptation methods follow fault tolerance mechanism that responds to a failure after a service quality violation. In other words, these methods are limited to responsive action. Therefore, a service-dependability-case based self-adaptation mechanism is necessary to preserve the dependability of the self-adaptive system. This paper demonstrates that the service-dependability-case based self-adaptation mechanism is better than QoS(quality of service)-based self-adaptation with fault tolerance to preserve the dependability of the self-adaptive system. Additionally, this paper suggests a method to present and analyze service dependability by using GSN(Goal Structuring Notation) which is the existing modeling method for the presentation of assurance cases, an action mechanism adapted using an analysis result of service-dependability-cases, a methods of leveraging the service-dependability-case based self-adaptation mechanism by following the service's life cycle, and the framework architecture including the major components and the interactions between the components in the control loop of the self-adaptation process.

• IE interfaces
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• v.23 no.1
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• pp.48-57
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• 2010

A tryout is one of the most important process in development and production of dies. For automotive press dies, it takes 3 to 4 months during the vehicle development process. Moreover, useful information and knowledge from tryout process is very important to design and production planning of dies. In this paper, we developed a new supporting system for making and managing tryout reports of an automotive press die. The CBDTS(Case-Based reasoning for Die Tryout report System) was developed and applied using case-based reasoning method in order to reduce time and manage knowledge of tryout. It consists of "Class Retrieval Wizard", "Case Cleansing Module", and "Case Viewer." Also, this CBDTS could be a channel to integrate field information with enterprise-wide information management systems as well. The CBDTS was applied to a Korean automotive press die shop, and the results were very satisfied in both quantitative and qualitative manners.

• KIISE Transactions on Computing Practices
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• v.21 no.2
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• pp.132-137
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• 2015

A real-time system is a system wherein the behavior of the system depends not only on the input but also on the timing of the input. Timed automata is a widely used model for real-time system modeling and analysis. Model-based testing is employed to check whether the system under test (SUT) works according to the model specifications by using test cases generated from models that represent software requirements. In this paper, a case study was performed applying the timed automata based testing tools, UPPAAL-TRON, UPPAAL-COVER and SYMBOLRT, to the same system. Comparison of the testing approaches and tools is then made based on the results of the case study.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.1
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• pp.48-53
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• 2010

In this paper, we develop the intelligent remote dust chamber bag control system which is combination of the advanced IT and traditional dust chamber based on event. At first, the message format is defined for the efficient dust chamber bag information transmission using power line communication. Also, we define the data types to logically model the dust chamber and the dust chamber bag, and they are logically modeled using XML and object-oriented modeling method. In addition to, we apply the case-based reasoning for showing the dust chamber bag exchange time intelligently to user at real-time using casebase, that is collected by case or case-based reasoning result, and that is described using XML.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.10a
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• pp.237-240
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• 2005

This paper describer a design expert system which determines the design values of shadow mask using Case-Based Reasoning. In Case-Based Reasoning, it is important to both retrieve similar cases and adapt the cases to meet the design specifications exactly. Especially, the difficulty in automating the adaptation process will prevent the designers from using the design expert systems efficiently and easily. This paper explains knowledge-based design support systems for shadow mask through neural network-based case adaptation. Specifically, we developed 1) representing design knowledge and 2) adaptive case-based reasoning method using RBFN (Radial Basis Function Network).

• Journal of Intelligence and Information Systems
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• v.9 no.2
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• pp.171-184
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• 2003

A project planning is one of the most important processes that determines success and failure of the project. A pre-project planning is also essential job for information system implementations at the early stage of project planning, especially for management information system like ERP. However, pre-project planning is very difficult, because lots of factors and their relationships should be considered. Pre-project planning of ERP implementation has been done by project manager's own knowledge and experiences. In this article, we propose a system that help project manager to make a pre-project plan of ERP project with case-based reasoning(CBR) framework. The proposed CBR system saves previous cases of ERP pre-project planning in the case base. Then, the system finds the most similar case with the current pre-project planning problem. Project manager can make a pre-project plan by adjusting the most similar case. From the interview with project managers, we collect some field cases of ERP implementation. We organized these cases by using XML(Extensible Markup Language), which is good for representing hierarchical information. XML gives us some flexibilities to correct and maintain cases. We make a prototype system, PPSS(Project Planning Support System) that help project manager to make a pre-project plan of ERP implementations. The object of the system is to support project manager to make a pre-project plan of ERP. We hope the result of the study can be applied to other information systems. Our research would be extended to cover other stages of project planning.

• Journal of Information Technology Application
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• v.1
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• pp.99-127
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• 1999

Under the concept of global economy, the enterprises are assigning design and production environments around the world in different areas. A serious problem of information exchange emerges as companies use traditional hardware and very distinct softwares appropriate to their field of expertise. To overcome the decreased productivity due to the interruption of information, the concept of simultaneous engineering and concurrent design becomes very significant. In this article, an agent-based ship design system is developed in order to support a cooperation in distributed ship design environments. Above all, the conflicts that occur in the middle of knowledge sharing in the system must be resolved. An approach to do this is the case-based conflict resolution strategy formulated to resolve current conflict on the basis of previous resolved similar cases in agent-based collaborative design system environments. To do this conflict cases that occur in initial ship design stage are extracted. On the basis of the extracted cases, case-base is constructed. In addition conflict resolution handler located in the facilitator is developed to treat conflict problems effectively by reasoning of the case-base and thus presenting an appropriate solution. The validation of developed case-based conflict resolution strategy is evaluated by applying to collaborative design process in initial ship design stage, especially the machinery outfitting design, the preliminary design, the hullform design, and the structural design. Through the help of the cooperation of the design agents, the facilitator, the conflict resolution handler, and the case-based system, a designer can be supported effectively in his/her decision-making based on the previous cases resolved similarly.

• Journal of the Korean Society of Safety
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• v.18 no.1
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• pp.50-55
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• 2003

This paper presents an intelligent computer system, which can easily diagnose electrical fire causes, without the help of human experts of electrical fires diagnosis. For this system, a database is built with facts and rules driven from real electrical fires, and an intellectual database system which even a beginner can diagnose fire causes has been developed, named as an Electrical Fire Causes Diagnosis System : EFCDS. The database system has adopted, as an inference engine, a mixed reasoning approach which is constituted with the rule-based reasoning and the case-based reasoning. The system for a reasoning model was implemented using Delphi 3, one of program development tools, and Paradox is used as a database building tool. To verify effectiveness and performance of this newly developed diagnosis system, several simulated fire examples were tested and the causes of fire examples were detected effectively by this system. Additional researches will be needed to decide the minimal significant level of the solution and the weighting level of important factors.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.81-86
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• 2002

In current CBR(Case-Based Reasoning) systems, the case adaptation is usually performed by rule-based method that use rules hand-coded by the system developer. So, CBR system designer faces knowledge acquisition bottleneck similar to those found in traditional expert system design. In this thesis, 1 present a model for learning method of case adaptation knowledge using case base. The feature difference of each pair of cases are noted and become the antecedent part of an adaptation rule, the differences between the solutions in the compared cases become the consequent part of the rule. However, the number of rules that can possibly be discovered using a learning algorithm is enormous. The first method for finding cases to compare uses a syntactic measure of the distance between cases. The threshold fur identification of candidates for comparison is fixed th the maximum number of differences between the target and retrived case from all retrievals. The second method is to use similarity metric since the threshold method may not be an accurate measure. I suggest the elimination method of duplicate rules. In the elimination process, a confidence value is assigned to each rule based on its frequency. The learned adaptation rules is applied in riven target Problem. The basic. process involves search for all rules that handle at least one difference followed by a combination process in which complete solutions are built.