• Korean Journal of Computational Design and Engineering
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• v.11 no.2
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• pp.148-155
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• 2006

This paper presents a new method for assessing the efficiency of production process plans using tolerance chart to lower production cost. The tolerance chart is used to predict the accuracy of a part that is to be produced following the process plan, and to carry out the quantitative measurement on the efficiency of the process plan. By comparing the values of design tolerances and their corresponding resultant tolerances calculated using the tolerance chart, the process plan that is incapable of satisfying the design requirements and the faulty production operations can be identified. Similarly, the process plan that imposes unnecessarily high accuracy and wasteful production operations can also be identified. For the latter, a quantitative measure on the efficiency of the process plan is introduced. The higher the unnecessary cost of the production, the poor is the efficiency of the process plan. A coefficient is introduced for measuring the process plan efficiency. The coefficient also incorporates two weighting factors to reflect the difficulty of manufacturing operations and number of dimensional tolerances involved. To facilitate the identification of the machining operations and the machined surfaces, which are related to the unnecessarily tight resultant tolerances caused by the process plan, a rooted tree representation of the tolerance chart is introduced, and its use is demonstrated. An example is presented to illustrate the new method. This research introduces a new quantitative process plan evaluation method that may lead to the optimization of process plans.

• Journal of KIISE:Software and Applications
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• v.31 no.10
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• pp.1400-1411
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• 2004

There are many cases that many XML documents have different DTDs in spite of having a similar structure and being logically same kind of document. For this reason, It occurs a problem that these XML documents have different database schema and are stored in different databases. So, in this paper, we propose an algorithm that unifies DTDs of these XML documents using the finite automata and the tree structure. The finite automata is suitable for representing repetition operators and connectors of DTD, and is a simple representation method for DTD. By using the finite automata, we are able to reduce the complexity of algorithm. And we apply a proposed algorithm to unify DTDs of science journals.

• Survey Research
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• v.5 no.1
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• pp.1-26
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• 2004

The aim of this study lies in answering the question "How to form weighting cells to enhance sample representativeness in telephone, Internet and mobile surveys\ulcorner". For this, we explored 2% raw data of Year 2000 Population and Housing Census of Korea looking for meaningful patterns for ownership of telephones, the usage of Internet and/or mobile phones. We found that telephone coverage rates vary significantly by household size; 84.6% for one member households, contrasting 98.5% for two-or-more member households. Thus, telephone survey samples need to be weighted differently in sub-groups by household size for proportional representation of target population. Searching socio-demographic factors influencing the use of Internet by C5.0 tree models, we found that education levels and the occupation (or housing type, the automobile ownership) are two most important factors in addition to gender and age. Thus, surveyor might form weighting cells by such factors at the stage of post-stratification or set quotas, a priori, proportional to size of the cells by such factors. For mobile surveys, we approached similarly and found that education levels and the occupation (or the automobile ownership, marriage status) are two additional factors that may be used in forming weighing cells or in setting quotas for cells.

• The Journal of the Korea Contents Association
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• v.6 no.6
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• pp.42-49
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• 2006

XML used rapid method of meta language representation in internet for information transmission. In addition to XML Schema used frequency specification to variety data type. This thesis designed to Simple Type meta model of XML schema using UML. But because structure of XML schema complicate and suppose variety data type we can recognize many difficult matter to user's apprehension and application of model properties that appeared UML. To way out of this matter this study could specified clearly to structured expression in XML schema meta model that is applied OCL specification and together, come up with method of detailed design to parse tree and token generation for lexical and symmentics analysis in compile step on this study foundation.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.485-491
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• 2012

This paper proposes 'Coding Unit Tree' based on quadtree efficiently with motion vector to represent splitting information of a Coding Unit (CU) in HEVC. The new international video coding, High Efficiency Video Coding (HEVC), adopts various techniques and new unit concept: CU, Prediction Unit (PU), and Transform Unit (TU). The basic coding unit, CU is larger than macroblock of H.264/AVC and it splits to process image-based quadtree with a hierarchical structure. However, in case that there are complex motions in CU, the more signaling bits with motion information need to be transmitted. This structure provides a flexibility and a base for a optimization, but there are overhead about splitting information. This paper analyzes those signals and proposes a new algorithm which removes those redundancy. The proposed algorithm utilizes a type code, a dominant value, and residue values at a node in quadtree to remove the addition bits. Type code represents a structure of an image tree and the two values represent a node value. The results show that the proposed algorithm gains 13.6% bit-rate reduction over the HM-1.0.

• Journal of Korea Society of Industrial Information Systems
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• v.4 no.4
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• pp.71-78
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• 1999

In this paper, we implemented an authoring system in which it's easy and flexible for user to author multimedia documents. It can be characterized by the following properties. First, it provides a visual interface for easy multimedia authorings and presentations and defines a causal relation that can manage changes of media duration. Second, it provides an internal representation using tree and thus supports an effective document parsing. It also supports a presentation engine for effective presentations and user interactions in run-time.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.3
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• pp.681-687
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• 2000

Ideograph is a truly unifies data and procedural dependencies, Ideograph can be used to assist various program optimization, such as common expression elimination, code motion, constant folding etc. In this paper, we design and implementation of the optimized abstract syntax tree using Ideograph. Ideograph has control flow information and data flow information for source program. So we use a Ideograph in order to produce a optimized Ideograph with control flow information and data flow information.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06c
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• pp.252-257
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• 2007

MusicXML은 다양한 전자악보 형식들이 음악을 악보로 표현하는데 있어 지니는 한계를 잘 극복하면서 응용성, 확장성 및 공개성 등의 장점으로 인해 현재 전자악보의 표준으로 가장 적합한 것으로 평가되고 있는 악보 형식이다. 그러나 MusicXML은 XML을 기반으로 한 텍스트 데이터이기 때문에 이러한 악보 형식을 실제 악보로 변환하거나 연주하는 것은 물론 실제 악보 내용을 기반으로 한 악보 검색이 용이하도록 적절한 데이터 구조로 표현하는 것이 필요하다. 본 논문에서는 MusicXML 악보에 대하여 다차원 속성 정보를 가진 데이터의 표현에 용이한 k-d 트리 기반 데이터 구조로 표현하는 방법을 제안한다. 논문은 또한 악보에 대한 k-d 트리 구조를 보다 다양한 응용에 활용할 수 있도록 k-d 트리를 확장하여 구조화하는 방법을 제시한다. 본 논문에서 제안한 방법은 특히 내용을 기반으로 한 악보 정보 검색에 유용하게 이용될 수 있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.873-876
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• 2003

Z-map model is the most widely used model for NC simulation and verification. But it has several limitations to get a high precision, to apply 5 axis machining simulation. In this paper, we tried to use quadtree for searching cutting region. Quadtree representation of two dimensional objects is performed with a tree that describes the recursive subdivision. By using these quadtree model. storage requirements were reduced. And also, recursive subdivision was processed in the boundries, so, useless computation could be reduced, too. To get more high Accuracy, we applied the supersampling method in the boundaries. The Supersampling method is the most common form of the antialiasing and usually used with polygon mesh rendering in computer graphics To verify quadtree model we compared simulated results with z-map model and enhanced z-map model

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.27-30
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• 2005

XML(Extensible Markup Language)이 데이터 표현(data representation)과 문서 교환(data exchange)의 표준으로 지정됨에 따라 데이터베이스(database, DB)에 XML 문서를 저장하고 질의하기 위한 연구가 활발히 진행되고 있다. 특히, 현재 주류를 이루고 있는 관계형 DB 에 저장하기 위한 XML 인덱싱(indexing) 기법에 대한 연구도 다양하게 진행되고 있다. 본 논문에서는 XML 문서를 관계형 DB 에 효율적으로 저장하고 질의하기 위한 방법으로서 기존의 트리(tree) 구조의 데이터를 관계형 DB 에 Nested Interval 인덱싱 기법을 적용하여 XML 문서를 저장하는 방법에 대해 연구한다. 기존의 저장 기법들의 경우 XML 문서를 효율적으로 질의하기 위한 인덱싱을 수행하기 때문에 입력 후 추가되는 노드(node), 혹은 노드 집합의 입력 시에는 전체 혹은 일부분의 XML 문서를 재-인덱싱 해야 하는 비효율이 있다. 그러나, Nested Interval 의 경우에는 재-인덱싱이 불필요하다. 본 논문에서는 기존의 트리 구조 데이터의 인덱싱 기법들에 대한 비교와 함께 Nested Interval 을 이용한 XML 문서의 인덱싱 기법에 대해 기술한다.