• The KIPS Transactions:PartC
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• v.8C no.2
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• pp.113-121
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• 2001

접근제어의 목적은 컴퓨팅 자원 및 통신 정보자원 등을 부당한 사용자로부터 사용되거나, 수정, 노출, 파괴와 같은 비합법적인 행위로부터 보호하는데 있다. 대표적인 보안 정책 중에서 Biba 모델은 정보의 무결성을 보장하지만 상업적인 환경에 적용되기는 다소 미흡하며, 역할기반 접근제어 정책은 상업적인 측면의 보안정책에 적용이 가능하지만 접근되는 객체의 중요도에 따른 보안등급이 고려되지 않았다. 본 논문에서는 Biba 모델의 보안등급을 역할기반접근제어 모델에 적용함으로써 주체가 해당 객체를 부당하게 변경하는 것을 방지함과 동시에 수많은 접근권한을 관리하는데 융통성을 제공한다. 그리고 제안한 접근제어 모델의 제약조건들을 정형 명세 언어인 Z언어를 통해 명확히 표현함으로써 정책 입안자나 프로그래머가 접근제어정책을 설계하고 구현하고자 할 때 프로그램 개발에 소요되는 시간을 단축할 수 있다. 또한, 제안한 모델을 망관리 객체의 연산과 등급을 갖는 역할과 제약조건을 사용하여 실제 운영되는 통신망 관리에 적용하여 봄으로써 정보의 무결성이 보장됨을 보였다.

• Journal of KIISE:Software and Applications
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• v.31 no.5
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• pp.677-696
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• 2004

Component-based software engineering (CBSE) composes reusable components and develops applications with the components. CBSE is admitted to be a new paradigm that reduces the costs and times to develop software systems. The high quality of component designs can be assured if the consistency and correctness among the elements of a component are verified with formal specifications. Current formal languages for components include only some parts of contracts between interfaces, structural aspects and behavioral aspects of component, component-based system, component composition and variability. Therefore, it is not adequate to use current formal languages in all steps of a component design process. In this paper, we suggest a formal language to specify component designs Component-Z. Component-Z extends Object-Z, adds new notations to specify components. It can be possible to specify interfaces, the inner structure of a component, inner workflows, and workflows among interfaces with Component-Z. In addition, Component-Z provides the notations and semantics to specify variability with variation points, variants and required interfaces. The relation between interfaces and components is defined with mapping schemas. Parallel operator is used to specify component composition. It can be possible to describe deployed components with the specifications of component-based systems. Therefore, the formal specification language proposed in this paper can represent all elements to design components. In the case study, we specify an account management system in a bank so that we show that Component-Z can be used in all steps of component design.

• 전기의세계
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• v.29 no.7
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• pp.460-470
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• 1980

The design of a control unit for a playback-type industrial robot is studied. Implemented for the cylindrical-coordinate type industrial robot with 5 degrees of freedom, the control unit constructed for the study consists of (i) z-80 .mu.p-based .mu.-computer control system (ii) Teach-Box for work command, and (iii) various softwares for generating signals for servo driving unit and operating the robot as playback-type. Softwares are developed by using high level Basic Language and low level z-80 Assembly Language for ease of programming and speed of program execution. To show the effectiveness, and example is included.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04a
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• pp.439-442
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• 2002

컴포넌트 명세는 컴포넌트와 클라이언트 사이의 계약으로 볼 수 있다. 하지만 현재의 컴포넌트 명세는 인터페이스 명세 언어(Interface Definition Language)와 정확성이 결여된 자연어로 작성된 명세에 의존하고 있다. 이러한 명세는 모호성, 불완전성, 모순등을 포함할 수 있다. 따라서 컴포넌트 명세는 이러한 점을 충분히 고려하여 진행되어야 하는데 본 연구에서는 EJB 컴포넌트의 코드 템플릿을 반영하여 요구사항을 Object-Z로 명세하고 이러한 명세로부터 컴포넌트를 구현하는 단계를 제시하였다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.7 no.3
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• pp.79-94
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• 1997

OMG (Object Management Group) published a security service specification, called CORBA (Common Object Request Broker Architecture) security reference model because the integration of security and object-oriented techniques was critical for successful deployment of distributed object systems. The CORBA security reference model treats access control as an implementation independent semantic concept but has incomplete semantics of the access control function. Because of such imcompleteness it is difficult for the system administrator and the CORBA security implementor to have the same understanding for the meaning of access control in the CORBA security. We propose a formal model for access control the CORBA security using the formal description language, which is called Z language based on typed set theory. The proposed model provides concrete semantics of the access control function to both the system administrator and the implementor.

• English Language & Literature Teaching
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• v.11 no.4
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• pp.97-120
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• 2005

Production and perception of second language sounds are typically influenced by second language learners' native language sounds. In this study we investigate how the Korean language influences Korean speakers' production of English alphabets. In the experiment conducted to prepare for this study 16 native speakers of Korean pronounced English alphabets. Then three native speakers of English evaluated the Korean subjects' pronunciation of them. The results show that the Korean subjects' native language (i.e., Korean) influences their production of the English alphabets. When Korean has sounds corresponding to English alphabets, the English subjects rate the Korean subjects' production of them good. For instance, Korean has voiceless stop phonemes, hence their production of English alphabets was rated good by the English subjects. The Korean subjects' production of English alphabets containing the sounds that do not exist in Korean was rated poor by the English subjects. For instance, Korean does not have voiced fricative phonemes, hence their production of English alphabets was rated poor.

• Journal of Appropriate Technology
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• v.7 no.2
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• pp.172-187
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• 2021

In remote villages without access to modern IT technology, simple devices such as smartcards can be used to carry out business transactions. These devices typically store multiple business applications from multiple vendors. Although devices must prevent malicious or accidental security breaches among the applications, a secure communication channel between two applications from different vendors is often required. In this paper, first, we propose a method of establishing secure communication channels between applications in embedded operating systems that run on multi-applet smart cards. Second, we enforce the high assurance using an intransitive noninterference security policy. Thirdly, we formalize the method through the Z language and create the formal specification of the proposed secure system. Finally, we verify its correctness using Rushby's unwinding theorem.

• Journal of the Korea Society of Computer and Information
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• v.18 no.1
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• pp.123-136
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• 2013

The Feature model can not be guaranteed the syntactic accuracy of its model and be difficult the validation using automatic tool for its syntax, because this model is expressed by a graphical and informal structure in itself. Therefore, there is a need to formalize and check for the feature model, to precisely define syntax for construct of the model. This paper presents a Z formal specification and a model checking mechanism of the feature model to guarantee the correctness of the model. It first defines the translation rules between feature model and Z, and then converts the syntax of the feature model into the Z schema specification by applying these rules. Finally, the Z schema specification is checked syntax, type, and domain errors using the Z/Eves validation tool to assure the correctness of its specification, With the use of the proposed method, we may express more precisely the construct of the feature model. Moreover the domain analyst are able to usefully verify the errors of the generated feature model.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.457-466
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• 2021

This study sought to identify the effectiveness of training programs by developing mobile app-based training programs to enhance memory, attention, and language function, which is known to be vulnerable to menopause women. It was conducted on 40 Climacteric woman between 40 to 60 years complaining about cognitive function decline. The mobile app-based cognitive training was an 8 week program. There were a total of 24 sessions and each session took 20-30 minutes, three times per week. The survey was carried out including a baseline study pre and post intervention study. The research variables were objective cognitive function (overall cognitive function, memory, attention, and language function), subjective cognitive function and quality of life. The cognitive training program showed a significant increase in overall cognitive function(t=-8.688, p<.001), memory(t=-4.765, p<.001), attention : number of correct answers(t=-7.293, p<.001), language high frequency response speed(Z=-2.179, p=.036), language low frequency response speed(Z=-2.737, p=.009) and quality of life (t=-3.358, p=.002). However, there was no significant difference in the scores for subjective cognitive function. The cognitive training program was found to be an effective intervention for improving the cognitive function of Climacteric women. It could be used as a cognitive intervention tool that is accessible at home without expert help.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.275-278
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• 1987

In this paper, a programming system for SCARA-type robots is designed, consisting of robot language, computational facilities and programming tools for handling interconnection environments. In designing the robot language, CLRC(C Library for Robot Control) is introduced, using the general-purpose language 'C' as base programming language. Also the motion primitives for Continuous Path control as well as Point-To-Point motion arc included. By means of frame and homogeneous transformations the system is capable of applying the SCARA-type robot efficiently and easily for any given task.