• Structural Engineering and Mechanics
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• v.22 no.6
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• pp.665-683
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• 2006

The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatly influenced by the properties of constitutive materials, the laminate structures, and load conditions etc, accompanied by many uncertainty factors. So the reliability study on FRP is an important subject of research. Many achievements have been made in reliability studies based on the probability theory, but little has been done on the roles played by fuzzy variables. In this paper, a fuzzy reliability model for FRP laminates is established first, in which the loads are considered as random variables and the strengths as fuzzy variables. Then a numerical model is developed to assess the fuzzy reliability. The Monte Carlo simulation method is utilized to compute the reliability of laminas under the maximum stress criterion. In the second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of the fact that there may exist a series of states between the failure state and the function state, a fuzzy assumption for the structure state together with the probabilistic assumption for strength parameters is adopted to construct the GFRM of composite materials. By defining a generalized limit state function, the problem is converted to the conventional reliability formula that enables the first-order reliability method (FORM) applicable in calculating the reliability index. Several examples are worked out to show the validity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivity analysis shows that some of the mean values of the strength parameters have great influence on the laminated composites' reliability. The differences resulting from the application of different failure criteria and different fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, and can provide an effective and synthetic method to evaluate the reliability of a system with different types of uncertainty factors.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.229-234
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• 2008

XBRL is fundamentally defined as a structure that enterprises expand based on KGAAP 2.1 developed by the Korea branch of XBRL. Each enterprise selects its type of business and must check and choose the tag suitable to each enterprise. Since a complicated part such as expanding tag exists, there is a difficulty to prepare document through the step of tag expansion and data input. Although the expressive way of style provides the standards using the presentation structure and label structure provided fundamentally by XBRL, there is a complicated problem of using XBRL Processor. The electronic public disclosure system of the Financial Supervisory Service (DART) and Korea Exchange (KIND, KEDIS) use the Markup Language of SGML, XML and XBRL as format language. The procedure of defining document and process method vary in accordance with the characteristics of each language. This study analyzes the effect by step in accordance with format language of each electronic disclosure system and studies a direction of format language.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.528-538
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• 2011

In this study, we investigated the thinking processes of 7th grade science-gifted students in designing application experiments and analyzed their performance levels in the categorized processes. The analyses of the results revealed that they considered 'setting a problem situation,' 'deciding a strategy,' 'identifying the assumptions,' 'defining the measurements,' and 'validating the assumptions' in the processes of designing experiments. However, their performance levels of the categorized processes were found to be rather low. It was especially insufficient in setting the situations concretely appropriated to solve the problems and checking their own thinking critically by proper criteria. Therefore, we suggested a potential learning strategy for designing experiments such as replacing difficult and abstract situations to concrete and familiar situations. These results may offer some implications in developing an education program for science-gifted students to foster creativity by emphasizing scientific thinking skills such as experiment design ability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.11
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• pp.955-962
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• 2016

In recent years, there have been emerging needs for standardized software-based motion application development for better scalability and support for multiple operation modes for small quantity batch production. Although a software-based motion system provides a basis for constructing multiple operation modes on a machine, it is not easy to construct such systems without tools for defining multiple motion operation modes and standardized mode-change protocols. This paper proposes a motion recipe concept to overcome this problem; the concept includes the authoring of multiple motion operation modes using the PLCopen-compliant motion function blocks and communication protocols to trigger operation mode changes from an external interface. The motion recipe was implemented by extending an IEC 61131-3 compliant IDE called Beremiz, and the correctness of the motion recipe-based application behavior was verified on a real testbed.

• Journal of KIISE:Software and Applications
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• v.36 no.7
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• pp.531-538
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• 2009

Domestic software market is struggling with product's low quality and low return-on-investment. The cause for the problems is due to unclear requirements at the early stage of software project. Studies show that, to lessen the problem, the requirements specification must reflect the right project scope and quantifiable quality goal. To achieve such features, this paper describes a standard guideline for SRS (Software Requirements Specification), which helps in defining the scope of project, measuring and quantifying quality, linking and tracing of requirements, and improving usability. The proposed SRS enables separating the requirements analysis activity from implementation activity and thus can improve subcontract management process in software project.

• The KIPS Transactions:PartD
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• v.12D no.7 s.103
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• pp.1007-1016
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• 2005

A key issue for process language design is balancing the need for semantic richness with the need for ease of use. Most process modeling languages fail to satisfy above two conflicting aspects, which is an impediment to the widespread adoption of process modeling languages in the software industry despite of a variety of software process language studies. This paper describes a process modeling language RAiSE attempting to resolve such problem and presents the result of applying RAiSE to a well-known benchmark process, ISPW-6 software process example. RAiSE provides rigorous, yet clear semantics through combing essential features in various modeling paradigms and defining them in a well-structured graphical notation. Process models represented in RAiSE are interpreted and enacted by process engine implemented using CLiPS, a rule based expert system tool.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.7
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• pp.90-97
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• 2002

Wall slip models are essential to the study of nonequilibrium gas transport in rarefied and microscale condition that can be found in gas flows associated with aerospace vehicle, propulsion system, and MEMS. The Maxwell slip model has been used for this type of problem, but it has difficulty in defining the so-called accommodation coefficient and has not been very effective in numerical implementation. In the present study, on the basis of Langmuir's theory of the adsorption of gases on metals, a physical slip model is developed. The concept of the accommodation coefficient and the difference of gas particles are clearly explained in the new model. It turned out that the Langmuir model recovers the Maxwell model in the first-order approximation. The new models are also applied to various situations including internal flow in a microchannel. Issues of validation of models are treated by comparing analytic results with experiment.

• Journal of Internet Computing and Services
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• v.4 no.1
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• pp.39-52
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• 2003

As software is developed for many applications and software defects have caused serious problem sin those applications, the concern of software quality evaluation increases rapidly. Although there has been many efforts for establishing standards for software evaluation, such as ISO/IEC 9126, they provide only a framework for defining quality characteristics and evaluation process. They, however, do not provide practical guidances for deriving resonable weight value criteria for software evaluation. This paper presents a method to draw quantitative weight values from evaluator's subjective data in the process of software evaluation as observing the ISO/IEC 9126 standard. To eliminate the evaluators' subjectiveness and the uncertainty of weight value during evaluation, the Dempster-Shafer (D-S) theory is adopted and utilized. In this paper, the D-S theory is supplemented with an improved merge rule to reduce the bias of weight value when they are merged with other evaluator's weight value. The proposed merge rule has been tested and proved with actual evaluation data.

• Journal of KIISE:Software and Applications
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• v.26 no.12
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• pp.1531-1541
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• 1999

프로그래밍 언어의 의미를 정형적으로 표기하는 기법인 액션의미론을 기반으로 한 컴파일러 생성기는 프로그래밍언어의 액션의미구조가 주어지면 그 언어의 컴파일러를 자동으로 생성한다. 생성된 컴파일러는 먼저 원시 프로그램을 그에 상응하는 액션 프로그램으로 확장한 후, 목적 프로그램으로 컴파일 한다. 여기서 액션 프로그램은 일종의 중간코드로 쓰이므로, 효율적인 목적코드를 생성하기 위해서 중간코드의 성능향상이 필요하다. 본 논문에서는 액션 프로그램을 부분계산을 통해 효율적인 코드로 자동 변환해 주는 온라인 액션 부분계산기를 설계하고 구현한다. 선행 연구된 오프라인 방식에서 전역분석을 하지 않고는 불가능했던 요약캡슐의 몸통, 펼치기의 몸통에 대한 부분계산이 온라인 방법을 사용하면 가능함을 보이고, 명령형 액션의 부분계산도 추가적으로 수행할 수 있도록 확장한다. Abstract Action Semantics is a framework for formally defining the semantics of programming languages. Action semantics-directed compiler generators take an action semantics definition of a programming language and automatically generate a compiler of the language. The generated compiler first expands a source program into an action denotation of the program, and then compiles it to a target code. In these compiler-generation systems, it is important to statically process the expanded action denotation - used as an intermediate code - as much as possible so that the generated compiler can produce better target code. In this paper, we develop an automatic action-transformation method based on online partial evaluation. The previous off-line method was rather weak because it could not partially evaluate actions inside the body of abstraction and unfolding-action without performing separate global analysis. The proposed online method remedies the problem, thus naturally improves the quality of residual actions. Moreover, we also extend the method to partially evaluate imperative actions.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.3 s.21
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• pp.115-122
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• 2002

The mainly used technique to rectify satellite images with distortion is to develop a mathematical relationship between the pixel coordinates on the image and the corresponding points on the ground. By defining the relationship between two coordinate systems, a polynomial model is designed and various linear transformations are used. These GCP based geometric correction has performed overall plane to plane mapping. In the overall plane mapping, overall structure of a scene is considered, but local variation is discarded. The highly variant height of region is resampled with distortion in the rectified image. To solve this problem, this paper proposed the TIN-based rectification on a satellite image. The TIN based rectification is good to correct local distortion, but insufficient to reflect overall structure of one scene. So, this paper shows the experimental result and the analysis of each rectification model. It also describes the relationship GCP distribution and rectification model. We can choose a geometric correction model as the structural characteristic of a satellite image and the acquired GCP distribution.