• 제목/요약/키워드: Formal Methods

검색결과 521건 처리시간 0.029초

정형기법을 이용한 PLC RTOS 검증 (PLC Real Time OS Verification & Validation in Formal Methods)

  • 최창호;송승환;윤동화;황성재
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2489-2491
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    • 2005
  • Currently, Programmable Logic Contorller(PLC) uses Real Time Operation System(RTOS) as basic OS. RTOS executes defined results as to defined time. General features of RTOS emphasize the priority in each task, high-speed process of external interrupt, task scheduling, synchronization in task, the limitation of memory capacity. For safety critical placement, PLC software needs Verification and Validation(V&V). For example, nuclear power plant. In this paper, PLC RTOS is verified by formal methods. Particularly, formal method V&V uses verification tool called 'STATEMATE', and shows the results.

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보안기능 정형화 설계방법 연구 (Formal Specification for Secure Functions)

  • 유희준;최진영;김우곤
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2000년도 제13회 춘계학술대회 및 임시총회 학술발표 논문집
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    • pp.349-355
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    • 2000
  • 본 논문에서는 정형 명세 언어 Z를 이용하여 사용자 인증에 사용되어지는 MD5 Message Digest 알고리즘을 정형 명세 방법론에 따라서 명세 한 경험을 기술한다. 인터넷 기술의 발달로 인하여 통신상에서의 전자 상거래가 활성화되면서 서비스를 이용하는 사용자들에 대한 사용자 정보 보안과 보안 시스템에 접근하는 사용자에 대한 사용자 인증에 관한 문제가 매우 중요하게 부상되고 있다. 이 문제를 해결하기 위해서 보안에 관련된 많은 암호화 기법과 알고리즘이 개발되고 있고, 전세계적으로 이런 알고리즘으로 구현된 보안 시스템의 등급을 나누고 있다. 이런 보안 등급에서 일반적으로 정형기법을 사용하여 구현된 보안 상품이 최상의 평가를 받고 있다. 하지만, 국내에서는 이러한 분야에 대한 연구가 전무한 상태여서 어떠한 기준을 적용하는 것이 좋은 지를 판단하기가 매우 어려운 실정이다. 따라서, 본 논문에서는 이러한 문제에 대한 연구로 정형 명세 언어를 이용해서 인증 알고리즘을 명세하고 검토하는 작업을 수행한 경험을 기술한다.

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ForTIA: LOTOS 기반의 정형기법 지원도구 (ForTIA : A Tool Supporting Formal Method based on LOTOS)

  • 조수선;천윤식;오영배;정연대
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제6권2호
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    • pp.161-172
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    • 2000
  • 본 논문에서는 ForTIA라 불리는 LOTOS 지원도구의 개발을 소개한다. ISO 표준 정형 명세 언어인 LOTOS는 사용자의 요구사항이나 시스템 모형을 추상화하여 정형적으로 작성할 수 있도록 함으로써 구현에 이르기 전에 명세 상에서 시스템을 확인 및 검증할 수 있게 한다. ForTIA는 LOTOS 정형기법이 산업계에 적용될 수 있도록 확인 위주의 경량 정형기법 기능을 제공한다. ForTIA의 핵심적인 기능은 명세 시뮬레이션과 C++ 코드 생성이다. 시뮬레이션은 편리하고 직관적인 상호작용을 위한 트리 기반의 시각적 명세확인 메카니즘을 제공하고 C++코드생성은 LOTOS로부터 완전한 C++ 코드를 생성하여 시스템의 실제 구현에 이용될 수 있도록 한다.

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실내이미지 유형별 모델 개발에 관한 연구 (A Study on the Models Corresponding to Interior Image Types)

  • 방희조;박영순
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 1999년도 춘계학술발표대회 논문집
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    • pp.94-97
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    • 1999
  • The purpose of this study was to prepare the visual communication tool, which would be used for the interior design consulation to reduce the communication gap between an interior designer and a client. To achieve the study purpose, review of literature, questionnaire survey, qualitative analysis and design research methods were used. The major results of this study were as follows: 1) "Image Cube" was designed as a comprehensive rule to classify interior image types. By this, eight interior image types were classified: SFU(Simple-Formal-Urbane), SFN(Simple-Formal-Natural), SCU(Simple-Casual-Urbane), SCN(Simple-Casual-Natural), DFU(Decorative-Formal-Urbane), DFN(Decorative-Formal-Natural), DCU(Decorative-Casual-Urbane), DCN(Decorative-Casual-Natural). 2) The Interior image collages were composed to present the overall feeling of each interior image type. 3) The Interior image models which would be used as the standard to be modified to various sub-types through the interior design consultation were produced corresponding to interior image types.age types.

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Formal Analysis of Automatic Train Protection and Block System for Regional Line Using VDM++

  • Xie, Guo;Hei, Xinhong;Mochizuki, Hiroshi;Takahashi, Sei;Nakamura, Hideo
    • International Journal of Railway
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    • 제5권2호
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    • pp.65-70
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    • 2012
  • This paper introduced a novel railway system, Automatic Train Protection and Block (ATPB) briefly, which is proposed to improve the efficiency of existing regional train lines with low cost in Japan. The biggest superiority of ATPB system is a great use of universal and mature technologies, such as GPS and regular mobile telephone networks, so that there is nearly no increment of trackside equipments in the reconstruction. Then in order to guarantee the system safety, a formal model of ATPB is established and analyzed by formal method VDM++. Firstly, the specification is specified by VDM++ formally without ambiguity. Secondly, its internal consistency is proved by discharging the proof obligations. And finally, its satisfiability is checked by systematic testing, which executes specification and checks the outputs against corresponding inputs.

조현병에서 형식적 사고장애의 임상적 특성 (Clinical Characteristics of Formal Thought Disorder in Schizophrenia)

  • 양채영;김한성;김은경;김일빈;박선철;최준호
    • 생물정신의학
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    • 제28권2호
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    • pp.70-77
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    • 2021
  • Objectives Our study aimed to present the distinctive correlates of formal thought disorder in patients with schizophrenia, using the Clinical Language Disorder Rating Scale (CLANG). Methods We compared clinical characteristics between schizophrenia patients with (n = 84) and without (n = 82) formal thought disorder. Psychometric scales including the CLANG, the Brief Psychiatric Rating Scale (BPRS), the Young Mania Rating Scale (YMRS), the Calgery Depression Scale for Schizophrenia (CDSS) and the Word Fluency Test (WFT) were used. Results After adjusting the effects of age, sex and total scores on the BPRS, YMRS and WFT, the subjects with disorganized speech presented significantly higher score on the abnormal syntax (p = 0.009), lack of semantic association (p = 0.005), discourse failure (p < 0.0001), pragmatics disorder (p = 0.001), dysarthria (p < 0.0001), and paraphasic error (p = 0.005) items than those without formal thought disorder. With defining the mentioned item scores as covariates, binary logistic regression model predicted that discourse failure (adjusted odds ratio [aOR] = 5.88, p < 0.0001) and pragmatics disorder (aOR = 2.17, p = 0.04) were distinctive correlates of formal thought disorder in patients with schizophrenia. Conclusions This study conducted Clinician Rated Dimensions of Psychosis Symptom Severity (CRDPSS) and CLANG scales on 166 hospitalized schizophrenia patients to explore the sub-items of the CLANG scale independently related to formal thought disorders in schizophrenia patients. Discourse failure and pragmatics disorder might be used as the distinctive indexes for formal thought disorder in patients with schizophrenia.

공간 프로세스 대수를 이용한 정형 명세와 분석에서의 시간속성의 시각화 (Visual Representation of Temporal Properties in Formal Specification and Analysis using a Spatial Process Algebra)

  • 온진호;최정란;이문근
    • 정보처리학회논문지D
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    • 제16D권3호
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    • pp.339-352
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    • 2009
  • 유비쿼터스 컴퓨팅 환경에서 분산된 실시간 시스템의 행위와 공간, 시간 속성을 분석하고, 검증하기 위한 다양한 정형기법들이 존재한다. 그러나 대부분의 경우 공간과 행위를 같이 표현하는 구조적, 근본적 한계가 존재한다. 게다가 시간 속성이 포함되는 경우는 더욱 복잡해지게 된다. 이러한 한계를 해결하기 위하여 본 논문은 Timed Calculus of Abstract Real-Time Distribution, Mobility and Interaction(t-CARDMI)라는 새로운 정형기법을 제안한다. t-CARDMI는 행위의 표현으로부터 공간정보의 표현을 분리시켜 복잡도를 단순화 시키며, 시간 속성에 대해서 오직 행위적 표현에서만 허용하여 복잡한 명세를 덜 복잡하게 표현한다. t-CARDMI는 대기기간, 실행시작 만족시간, 실행시간, 실행완료 만족시간 등의 특유의 시간속성을 이동과 통신의 행위에서 모두 포함하는 특징을 갖는다. 새롭게 제안된 Timed Action Graph(TAG)는 공간과 시간을 포함하는 시스템의 명세를 분석하고 검증하기 위해서 공간과 시간속성을 2차원의 다이어그램으로 표현하며 그 안에서 이동과 통신의 정보를 분산된 그림정보로 표현하는 그래프로 t-CARDMI를 좀더 효율적으로 명세하고 분석할 수 있는 방법을 제공한다. t-CARDMI는 유비쿼터스 컴퓨팅에서의 분산된 실시간 시스템의 공간적, 행위적, 시간적 속성에 대한 명세, 분석 및 검증에 매우 효율적이고 효과적인 혁신적인 정형기법의 하나로 고려될 수 있다. 본 논문은 t-CARDMI의 문법과 의미, TAG 그리고 Specification, Analysis, Verification, and Evaluation (SAVE)로 명명된 툴을 제안하고 유비쿼터스 헬스케어 시스템 예제를 통해 효율성을 분석한다.

남성정장 상.하의 그레이딩에 관한 연구 (A Study on the Pattern Grading for Men's Formal Wear)

  • 백경자;유경진;이정란
    • 한국의류학회지
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    • 제26권6호
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    • pp.843-852
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    • 2002
  • The purpose of this study was to propose a computer-based grading method for men's formal wear according to the sizing systems based on the size and dimension whereby manufactured men's formal wear can be classified. The following procedures were as follows : 1) We surveyed the sizing systems and the computer-grading methods that have been used and presently practiced by the domestic garment industry of the ready-made men's wear. 2) Using the survey data of the domestic men's ready-made clothing industry and that of the National Anthropometric Survey of Korea in 1997, we proposed the new sizing and grading systems of men's formal wear within the framework of the Korean Garment Industry's directions and the data of the domestic men's ready-made clothing industry. 3) The suitability of the new grading systems to the domestic garment industry were put to a wearing teat. The findings were as follows : 1) Survey of the domestic ready-made garment industry showed that each company classified its own manufactured goods according to its own sizing and grading systems. 2) The superiority of the grading system was been demonstrated by a high approval rate of the subjects who participated in the testing.

한국의 현대 실내공간에 나타난 한국적 조형의식에 관한 연구 (The Study on the Korean Plastic Consciousness of the Contemporary Interior Space in Korea)

  • 오인욱
    • 한국실내디자인학회논문집
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    • 제13권5호
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    • pp.74-81
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    • 2004
  • The three basic elements of human life -clothing, food and shelter- had been evolved through different periods and cultural realms, as their spatial applications show distinct characteristics that are manifested through sensibilities only inherent to its specific culture. Especially in the interior spaces, possibilities to approach them in three-dimensional aspects allow formal characteristics to be expressed that are distinct to the country. Formal sensibilities embedded in interior space In Korea also follows such pattern, developed through various contemporary interpretations of Korean traditional formal sensibilities, including harmony with nature, simplicity, lightness, real and fake, and principle of harmony are being redefined by spatially expressed in contemporary language. That is, traditional formal sensibilitiesare filtered through various application methods such as composition, negotiation and modification, accommodating spatial manifestations to be not simply preserved nor replicated, but rather reconstructed through metaphor, symbol, abstraction and contrast. From this perspective, the Korean traditional formal sensibilitiesis not a notion fixed in the past, but a distinct perspectives evolving throughout periods of time that are constantly reconsidered and reinterpreted in our interior space. By examining Korean sensibilities manifested in interior space in the both diachronic aspects of tradition vs. contemporary, as well as synchronic aspects among various disciplines simultaneously, we would be able to generate a linkage to the dichotomous categories of tradition and contemporary.

Formal Validation Method and Tools for French Computerized Railway Interlocking Systems

  • Antoni, Marc
    • International Journal of Railway
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    • 제2권3호
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    • pp.99-106
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    • 2009
  • Checks and tests before putting safety facilities into service as well as the results of these tests are essential, time consuming and may show great variations between each other. Economic constraints and the increasing complexity associated with the development of computerized tools tend to limit the capacity of the classic approval process (manual or automatic). A reduction of the validation cover rate could result in practice. This is not compatible with the French national plan to renew the interlocking systems of the national network. The method and the tool presented in this paper makes it possible to formally validate new computerized systems or evolutions of existing French interlocking systems with real-time functional interpreted Petri nets. The aim of our project is to provide SNCF with a method for the formal validation of French interlocking systems. A formal proof method by assertion, which is applicable to industrial automation equipment such as interlocking systems, and which covers equally the specification and its real software implementation, is presented in this paper. With the proposed method we completely verify that the system follows all safety properties at all times and does not show superfluous conditions: it replaces all the indoor checks (not the outdoor checks). The advantages expected are a significant reduction of testing time and of the related costs, an increase of the test coverage rate, an answer to the new demand of railway infrastructure maintenance engineering to modify and validate computerized interlocking systems. Formal methods mastery by infrastructure engineers are surely a key to prove that more safety is not necessarily more expensive.

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