• Title/Summary/Keyword: formal approach

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The Effectiveness of Learning Cycle Approach to Change the Concept of Density (밀도의 개념 변화에 미치는 순환학습의 효과)

  • Hong, Soon-Kyung;Choi, Byung-Soon
    • Journal of The Korean Association For Science Education
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    • v.11 no.1
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    • pp.15-24
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    • 1991
  • The purpose of this study was to investigate the effectiveness of Learning Cycle approach to change the concept of density. The results of the study were as follows : 1) Students already had various types of preconception related to density before formal learning. These preconceptions mostly differ from scientific concepts. 2) Male students were much better than female ones in the development of scientific concepts before formal learning. These differences were found statistically significant(P<0.01). 3) The higher the cognitive level of the students, the better the development of scientific concepts. 4) In the change of preconceptions to scientific concepts by treatment, there was significant difference between control group and experimental group at the 0.05 level. It was found that Learning Cycle approaches were more effective than traditional approaches in acquiring the concept of density. 5) It was found that there was no significant difference On the retention level of the concept of density between control group and experimental group.

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On the Balanced Blending of Formally Structured and Simplified Approaches for Utilizing Judgments of Experts in the Assessment of Uncertain Issues

  • Ahn Kwang-Il;Yang Joon-Eon;Ha Jae-Joo
    • Nuclear Engineering and Technology
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    • v.35 no.4
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    • pp.318-335
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    • 2003
  • Expert judgment is frequently employed in the search for the solution to various engineering and decision-making problems where relevant data is not sufficient or where there is little consensus as to the correct models to apply. When expert judgments are required to solve the underlying problem, our main concern is how to formally derive their technical expertise and their personal degree of familiarity about the related questions. Formal methods for gathering judgments from experts and assessing the effects of the judgments on the results of the analysis have been developed in a variety of ways. The most important interest of such methods is to establish the robustness of an expert's knowledge upon which the elicitation of judgments is made and an effective trace of the elicitation process as possible as one can. While the resultant expert judgments can remain to a large extent substantiated with formal elicitation methods, their applicability however is often limited due to restriction of available resources (e.g., time, budget, and number of qualified experts, etc) as well as a scope of the analysis. For this reason, many engineering and decision-making problems have not always performed with a formal/structured pattern, but rather relied on a pertinent transition of the formal process to the simplified approach. The purpose of this paper is (a) to address some insights into the balanced use of formally structured and simplified approaches for the explicit use of expert judgments under resource constraints and (b) to discuss related decision-theoretic issues.

A Process Algebra Approach for Object Interactions in UML (UML에서 객체 상호작용에 대한 프로세스 대수 접근)

  • 최성운;이영환
    • Journal of KIISE:Software and Applications
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    • v.30 no.3_4
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    • pp.202-211
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    • 2003
  • Abstract Formal definitions of syntax and semantics for the static and dynamic models in Object Oriented methods are already defined. But the behavior of interacting objects is not formalized. In this paper, we defined the common behavior of interacting objects in terms of process algebra using sequence diagram in UML and regularized properties of interacting objects. Based on the results, we can develop a formal specification by. using of the object interaction instead of the existence dependency suggested by M. Snoeck and G. Dedene[9].

Modeling and Validation of Semantic Constraints for ebXML Business Process Specifications (ebXML 비즈니스 프로세스 명세를 위한 의미 제약의 모델링과 검증)

  • Kim, Jong-Woo;Kim, Hyoung-Do
    • Asia pacific journal of information systems
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    • v.14 no.1
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    • pp.79-100
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    • 2004
  • As a part of ebXML(Electronic Business using eXtensible Markup Language) framework, BPSS(Business Process Specification Schema) has been provided to support the direct specification of the set of elements required to configure a runtime system in order to execute a set of ebXML business transactions. The BPS,' is available in two stand-alone representations, a UML version and an XML version. Due to the limitations of UML notations and XML syntax, however, current ebXML BPSS specification fails to specify formal semantic constraints completely. In this study, we propose a constraint classification scheme for the BPSS specification and describe how to formally represent those semantic constraints using OCL(Object Constraint Language). As a way to validate p Business Process Specification(BPS) with the formal semantic constraints, we suggest a rule-based approach to represent the formal constraints and demonstrate its detailed mechanism for applying the rule-based constraints to the BPS with a prototype implementation.

Verification Test of Communication Protocol for Interface between EIS and LDTS (철도신호설비 상호간 정보전송을 위한 통신 프로토콜 검증시험)

  • 황종규;이재호;윤용기;신덕호
    • Journal of the Korean Society for Railway
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    • v.7 no.2
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    • pp.114-119
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    • 2004
  • According to the computerization of railway signalling systems. the communication protocol for interface between these systems are required. Therefore the new communication protocol for railway signaling system is required. Generally, there are two verification method for new designed protocol in the industrial and academic fields. One is the laboratory testing method which is very popular and general technique. In our research the comparison between existing and new designed protocol for signaling is described and the verification test results are also represented. From these laboratory test, we are verified the conformance of new designed protocol. Another method is verified by formal method. The format verification method is widely used at safety-critical system design but this approach is nor popular at verification communication protocol. However it is very important to verify the safety of new designed protocol for railway signaling system because signaling systems are very safety-critical systems. So, the methodology for formal verification of designed protocol is also reviews in this paper.

Analyzing RDF Data in Linked Open Data Cloud using Formal Concept Analysis

  • Hwang, Suk-Hyung;Cho, Dong-Heon
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.6
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    • pp.57-68
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    • 2017
  • The Linked Open Data(LOD) cloud is quickly becoming one of the largest collections of interlinked datasets and the de facto standard for publishing, sharing and connecting pieces of data on the Web. Data publishers from diverse domains publish their data using Resource Description Framework(RDF) data model and provide SPARQL endpoints to enable querying their data, which enables creating a global, distributed and interconnected dataspace on the LOD cloud. Although it is possible to extract structured data as query results by using SPARQL, users have very poor in analysis and visualization of RDF data from SPARQL query results. Therefore, to tackle this issue, based on Formal Concept Analysis, we propose a novel approach for analyzing and visualizing useful information from the LOD cloud. The RDF data analysis and visualization technique proposed in this paper can be utilized in the field of semantic web data mining by extracting and analyzing the information and knowledge inherent in LOD and supporting classification and visualization.

Frame Analysis of Newspaper's Coverage Related to Leisure of Older Adults (노인여가관련 신문보도의 프레임 분석)

  • Oh, Sae-Sook;Kim, Jong-Soon;Shin, Kyu-Lee
    • Journal of Wellness
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    • v.7 no.2
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    • pp.25-37
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    • 2012
  • The purpose of this study was to analyze the mass media's news framing on the elderly leisure. For this, researchers collected news articles from daily newspapers such as Chosun Ilbo, Hankyoreh, Kyunghyang Shinmun, and analysed the news framing of them through text-analytic approach. Total of 153 news the about elderly leisure between 1990 and 2010 were used for frame analysis. The Frame analyses were divided by formal frame and content frame. The formal frame was formed by deduction based on the classification method of Iyergar(1991) and the content frame was formed by induction according to the analysis of overall themes and titles of news. The main result could be summarized as follows: First, the analysis of formal frame showed that the episodic frame was predominantly high which focused on specific event or occurrences about elderly leisure. Second, it was found by content frame analysis that elderly leisure's facilities, health, serious leisure, policy frame were main subjects of news framing.

A Formal Guidance for Handling Different Uncertainty Sources Employed in the Level 2 PSA

  • Ahn Kwang-Il;Yang Joon-Eon;Ha Jae-Joo
    • Nuclear Engineering and Technology
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    • v.36 no.1
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    • pp.83-103
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    • 2004
  • The methodological framework of the Level 2 PSA appears to be currently standardized in a formalized fashion, but there have been different opinions on the way the sources of uncertainty are characterized and treated. This is primarily because the Level 2 PSA deals with complex phenomenological processes that are deterministic in nature rather than random processes, and there are no probabilistic models characterizing them clearly. As a result, the probabilistic quantification of the Level 2 PSA CET / APET is often subjected to two sources of uncertainty: (a) incomplete modeling of accident pathways or different predictions for the behavior of phenomenological events and (b) expert-to-expert variation in estimating the occurrence probability of phenomenological events. While a clear definition of the two sources of uncertainty involved in the Level 2 PSA makes it possible to treat an uncertainty in a consistent manner, careless application of these different sources of uncertainty may produce different conclusions in the decision-making process. The primary purpose of this paper is to characterize typical sources of uncertainty that would often be addressed in the Level 2 PSA and to provide a formal guidance for quantifying their impacts on the PSA Level 2 risk results. An additional purpose of this paper is to give a formal approach on how to combine random uncertainties addressed in the Level 1 PSA with subjectivistic uncertainties addressed in the Level 2 PSA.

Generating LOTOS Specifications from UML Static Structure Diagrams (UML 정적구조 다이아그램으로부터 LOTOS 명세 생성)

  • Kim, Cheol-Hong;Ahn, Yu-Whoan;Lee, Won-Chun
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.12
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    • pp.3500-3513
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    • 1999
  • It is recognized that object-oriented methods and formal methods are two different main streams that will influence on the future direction of software engineering. A merging effort on these two technologies, named "a formal approach on system specifications using object-oriented methods" emerges rapidly and produces remarkable research results LOTOS is well-suited to an object-based approach. However, to provide a full object-oriented approach, we need to model generalization (i.e. inheritance and polymorphism). Most authors who have examined this topic have proposed extensions to LOTOS. As an extension of such an effort, this paper proposes a method that generates LOTOS specification from static structure diagrams in UML.

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A Qualitative Formal Method for Requirements Specification and Safety Analysis of Hybrid Real-Time Systems (복합 실시간 계통의 요구사항 명세와 안전성 분석을 위한 정성적 정형기법)

  • Lee, Jang-Soo;Cha, Sung-Deok
    • Journal of KIISE:Software and Applications
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    • v.27 no.2
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    • pp.120-133
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    • 2000
  • Major obstruction of using formal methods for hybrid real-time systems in industry is the difficulty that engineers have in understanding and applying the quantitative methods in an abstract requirements phase. While formal methods technology in safety-critical systems can help increase confidence of software, difficulty and complexity in using them can cause another hazard. In order to overcome this obstruction, we propose a framework for qualitative requirements engineering of the hybrid real-time systems. It consists of a qualitative method for requirements specification, called QFM (Qualitative Formal Method), and a safety analysis method for the requirements based on a causality information, called CRSA (Causal Requirements Safety Analysis). QFM emphasizes the idea of a causal and qualitative reasoning in formal methods to reduce the cognitive burden of designers when specifying and validating the software requirements of hybrid safety systems. CRSA can evaluate the logical contribution of the software elements to the physical hazard of systems by utilizing the causality information that is kept during specification by QFM. Using the Shutdown System 2 of Wolsong nuclear power plants as a realistic example, we demonstrate the effectiveness of our approach.

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