• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.3
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• pp.19-27
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• 2001

Accordingly it is very important to not only develop the stack of protocol, but also try an international standardization regarding the standard protocol of VoIP. Has compared to the advanced countries having already some success in commercialization, Korea is relatively much less involved in relation to this technology and endeavors. In this regards, this paper is focused on developing a protocol stack made with encoder/decoder, the generator or the header file, syntax analyzer etc. based on the protocol grammars of Session Description Protocol supported by IETF RFC2327. For the sake of it, first describe the SDP BNF grammar based on IETF RFC2327 Augmented BNF. And then we produce the Abstract Syntax Tree, header file generator for encoding/decoding as applying the method of syntax directed to SDP protocol grammar.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.149-158
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• 2005

The object of this paper is to develop the shortest path algorithm. The existing shortest path algorithm models are developed while considering travel time and travel distance. A few problems occur in these shortest path algorithm models, which have paid no regard to cognition of users, such as when user who doesn't have complete information about the trip meets a strange road or when the route searched from the shortest path algorithm model is not commonly used by users in real network. This paper develops a shortest path algorithm model to provide ideal route that many people actually prefer. In order to provide the ideal shortest path with the consideration of travel time, travel distance and road cognition, travel time is predicted by using Kalman filtering and travel distance is predicted by using GIS attributions. The road cognition is considered by using space data of GIS. Optimal routes provided from this paper are shortest distance path, shortest time path, shortest path considering distance and cognition and shortest path considering time and cognition.

• Journal of KIISE:Software and Applications
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• v.30 no.3_4
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• pp.268-277
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• 2003

A document type definition(DTD) which defines tags for a document is a XML document grammar that defines syntactic structure of a document. An XML document keeps the rules and must be parsed to check validation. To parse XML document, the deterministic parsing method of programming language is irrelevant because it does not satisfy the definition of deterministic content model in element declaration. In this paper, we consider editing of a valid XML document in syntax-directed editing environment, and we suggest the internal storage representations of syntax in DTD and theirs algorithms. The consequence is that a syntactic structure of textual DTD is transformed into graph and table structures. The table structure of DTD is interpreted the context free grammar which has attribute values and is used in syntax-directed editor for XML. We called this the XML abstract grammar and showed generated results and examples.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.6
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• pp.11-23
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• 2002

Computational models up to now for Korean morphology have been linear in that it deal with only segmentation of morphemes rather than formation of the internal structure of a word. When integrating a linear computational model with syntax analysis, it requires an additional interface component between this model and the syntax to bind morphemes into sentence constituents. Furthermore the linear model is not semantically intuitive. In this paper, based on word-syntactical viewpoint, we propose an integrated computational model that deals with morpheme segmentation, formation of syntactic element (sentence constituent), and even internal structure of word. Formalism of two-level morphology is employed to cope with morpheme segmentation and alternation problems, and functional diacritics are proposed to incorporate categorial context into the two-level formalism. A modified GLR-based algorithm is also proposed to check syntactical constraint of morphemes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.44-48
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• 2004

This paper proposes a phrase-based indexing system based on the phrase. the larger syntax unit than a single keyword. Early information retrieval systems with indexing system matching single keyword is simple and popular. But with single keyword matching it is very hard to represent the exact meaning of documents and the set of documents from retrieval is very large, therefore it can't satisfy the user of the information retrieval systems. Web documents include lots of syntactic errors, the natural language parser with high quality cannot be expected in Web. Partial trees, even not a full tree, from fully bottom-up parsing is still useful for extracting phrases, and they are much more discriminative than single keyword for index. It helps the information retrieval system enhance the efficiency and reduce the processing overhead, too.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.475-478
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• 2019

웹어플리케이션의 발전에 따라 자바스크립트 런타임 플랫폼인 Node.js 의 사용도 증가하고 있다. 개발자들은 Node.js 의 다양한 모듈을 활용하여 프로그래밍을 하게 되는데, Node.js 모듈 보안의 중요성에 비하여 모듈 취약점 분석은 충분히 이루어지지 않고 있다. 본 논문에서는 소스코드의 구조를 트리 형태로 표현하는 Abstract Syntax Tree 와 소스코드의 실행 흐름 및 변수의 흐름을 그래프로 나타내는 Control Flow Graph/Data Flow Graph 가 Node.js 모듈 취약점 분석에 효율적으로 활용될 수 있음을 서술하고자 한다. Node.js 모듈은 여러 스크립트 파일로 나누어져 있다는 점과 사용자의 입력이 분명하다는 특징이 있다. 또한 자바스크립트 언어를 사용하므로 선언된 변수들의 타입에 따라 적용되는 범위인 scope 가 다르게 적용된다는 특징이 있다. 본 논문에서는 이러한 Node.js 모듈의 특징을 고려하여 Abstract Syntax Tree 및 Control Flow Graph/Data Flow Graph 을 어떻게 생성하고 취약점 분석에 활용할 것인지에 대한 방법론을 제안하고, 실제 분석에 활용할 수 있는 코드 구현을 통하여 구체화시키고자 한다.

• Proceedings of the CALSEC Conference
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• 2004.02a
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• pp.332-335
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• 2004

Issues ·Bottom-up v.s. Top-down Development ＆ Evaluation ·Syntax-Directed v.s. Conceptual Modeling -Reusing and Easy understanding -User friendliness and Concrete Rules ·No Aligned Rules and Guidelines for Developing Document Structures from Conceptual Information Models(omitted)

• Proceedings of the Korean Society for Information Management Conference
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• 2001.08a
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• pp.189-192
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• 2001

모아쓰기식 어휘사전은 풀어쓰기에 비해 용언어간의 크기가 늘어나고 용언어미도 많이 증대된다. 본 논문에서는 초등학생을 위한 홈페이지에서 사용되는 어휘가 상대적으로 적기 때문에 용언어간과 어미, 명사와 조사를 조화시켜 간단한 모아쓰기식 기계사전을 제시하였다.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.2
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• pp.53-68
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• 2011

A selection of viewpoint is a first priority for landscape evaluation. However, it has been artificially carried out by a subjective method without of criterion. Therefore, this study proposed the objective and quantitative viewpoint selection methods using space syntax and GIS. For this, the study area on samduk3 residential improvement district located at Daegu city was divided into 24 sectors of visibility zone by distance and direction. After that, the preliminary viewpoints equally distributed in space were selected by axial map analysis of space syntax and viewshed-frequency analysis of GIS. According to the result of selection of the final viewpoints using the VEI(Viewpoint Evaluation Index), all the final viewpoints were placed in the National Debt Repayment Movement; VEI value of VP-2 was 112.63 in the foreground, VP-10 was 18.31 in the middleground and VP-18 was 5.55 in the background. Selected viewpoints were verified as a big changing of landscape variation and high chance of view such as the public area, the park and the high-density residential area. Thus, VEI will be used as a quantitative method of selecting viewpoints and it is expected to be able to use as the objective indicator.

• Journal of KIISE:Software and Applications
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• v.32 no.4
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• pp.290-299
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• 2005

Stealing the source code of a program is a serious problem not only in a moral sense but also in a legal sense. However, it is not clear whether the code of a program is copied from another or not. There was a program similarity checker detecting code-copy by comparing the syntax trees of programs. However this method has a limitation that it cannot detect the code-copy attacks when the attacker modifies the syntax of the program on purpose. We propose a program similarity check by program control graph, which reveals not only syntax information but also control dependancy. Our method can detect the code-copy attacks that do not change control dependancy Moreover, we define what code-copy means and establish the connection between code-copy and similarity of program control graph: we prove that two programs are related by copy congruence if and only if the program control graphs of these programs are equivalent. We implemented our method on a functional programming language, nML. The experimental results show us that the suggested method can detect code similarity that is not detected by the existing method.