• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.12
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• pp.1032-1039
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• 2012

The present paper deals with precise relative positioning of formation satellites with long baseline in low Earth orbit making use of L1/L2 dual frequency GPS carrier phase measurements. Kinematic approach means to describe the motion of objects without taking its mass/dynamics model into consideration. The advantage of the kinematic approach is that information about dynamics of the system is not applied, which gives more flexibility and could improve the scientific interest of the observations made by the mission. The ionosphere terms, which are not canceled by double differenced measurement equation in the case of the long baseline, are explicitly estimated as unknown parameters by extended Kalman filter. The estimated float ambiguities by EKF are solved by existing efficient integer vector search strategy under integer least square condition. For the integer vector search, we employ well known MLAMBDA. Finally, The feasibility and accuracy of processing scheme are demonstrated using the GPS measurements for two satellites in low Earth orbit separated by baselines of 100 km.

• Journal of Intelligence and Information Systems
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• v.14 no.1
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• pp.1-17
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• 2008

Data mining is defined as the process of discovering meaningful and useful pattern in large volumes of data. In particular, finding associations rules between items in a database of customer transactions has become an important thing. Some data structures and algorithms had been proposed for storing meaningful information compressed from an original database to find frequent itemsets since Apriori algorithm. Though existing method find all association rules, we must have a lot of process to analyze association rules because there are too many rules. In this paper, we propose a new data structure, called a Frequent Pattern Network (FPN), which represents items as vertices and 2-itemsets as edges of the network. In order to utilize FPN, We constitute FPN using item's frequency. And then we use a clustering method to group the vertices on the network into clusters so that the intracluster similarity is maximized and the intercluster similarity is minimized. We generate association rules based on clusters. Our experiments showed accuracy of clustering items on the network using confidence, correlation and edge weight similarity methods. And We generated association rules using clusters and compare traditional and our method. From the results, the confidence similarity had a strong influence than others on the frequent pattern network. And FPN had a flexibility to minimum support value.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.5
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• pp.540-550
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• 2002

Electronic Book(eBook) is a publication that stored and processed the contents of a book using digital mechanisms and has advantages such as easiness in saving and searching and the possibility of carrying. To activate Electronic Book which has the advantages mentioned above, studies on related techniques are required and a development of an editor exclusive for eBooks which is appropriate for eBook structure is still not adequate. In this paper, we design and implement Electronic Book editor providing form-based interface for eBook genre-based structure so that it would be easier for users to write. Especially because Electronic Book has genre-based structure due to the characteristic of literature, it is necessary to provide forms for each different genres. Therefore, compared to the problem of having to study XML grammar when writing Electronic Book using the existing XML editor, the proposed system can solve this problem by providing form-based interface. Additionally, with regard to the characteristic of eBook which have structures according to the intention of users, we provided the flexibility of adding dynamic forms to the form provided in default so that it will be more effective in writing Electronic Books. Therefore by providing form-based interface according to the genre and dynamic structure according to the intention of users, Electronic Book can be wrote more easily.

• Proceedings of the Technology Innovation Conference
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• 2002.02a
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• pp.205-221
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• 2002

본 연구의 목적은 정부출연연구소에서 연구개발된 기술이 민간부문에서 충분히 활용되지 못하고 있다는 문제의식으로부터 출발하여, 원천, 핵심기술의 확보가 국가경쟁력을 좌우하는 첨단기술경제시대에 막대한 국가자금으로 연구개발된 우수한 기술의 사장을 방지하고 궁극적으로 국가경제발전을 위한 전략적 기술이전 촉진 방안을 모색하는 것이다. 현재 국무총리산하 기초, 산업, 공공기술 연구회로 분류 조직되어 있는 3개 연구회 총 1개 정부출연연구소의 지난 10년간(1992-2001)의 연구예산규모, 보유특허수, 기술이전건수, 기술징수액, 기술실시계약서를 방문 조사하고 각 연구소의 기술이전전담조직의 실무자를 대상으로 설문 조사하여 설문 및 통계분석 결과를 토대로 기술이전관련 문제점 파악 및 기술이전 촉진을 위한 전략적 개선방안을 모색해 보았다. 먼저 기술이전 현황을 살펴보면 기술이전건수는 보유특허수의 3%미만, 기술료 징수액은 연구예산규모의 2%미만으로 기술이전 및 기술상업화율이 상당히 저조하다. 설문 및 통계분석 결과로부터 TLO 조직의 비효율적인 운영, 비전문성, 열악한 운영인력, 적극적인 기술이전을 위한 동기부족, 정부의 제도적인 지원부족, 기술실시계약서 조항들의 경직성 등을 기술이전 관련 문제점으로 도출해 낼 수 있었다. 이러한 문제점을 극복하고 기술이전 촉진을 위한 개선방안으로는 첫째, TLO 조직을 전략으로 개편해야 한다. 즉 기술이전 전담인력을 변리사, 전문 협상가, 연구원 둥 전문가들로 구성하여 지적재산권 관리, 기술평가, 시장조사, 기술마케팅, 사후관리 등을 효율적으로 수행해야 한다. 둘째, 정부의 정책적인 지원이 필요하다. 기술이전 전담조직에 대한 인센티브 시스템 기술이전을 위한 특별예산 편성 등을 정책적, 제도적으로 도입하는 등의 적극적인 지원이 요구된다. 셋째, 기술실시계약서 조항들을 기술실시자의 실질적인 기술 상업화에 도움이 되고 기술 유출 및 기술사장화를 방지하는 방향으로 개선하여야 한다. 특히, 전용실시권과 실시대가, 기술실시 및 지적재산권 관리와 관련된 제반 비용의 부담비율 등을 보다 유연하게 개선하여야 한다. 본 연구는 정부출연연구소에서 민간부문으로의 기술이전만을 고려하여 기술이전의 중요한 요소인 민간부문에 대한 고려가 전혀 없다. 따라서 보다 실질적이고 체계적인 결과를 도출하기 위해 민간부문을 고려한 연구가 진행되어야 한다고 생각한다.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.8
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• pp.547-565
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• 2009

Simulation is the imitation of some real thing, state of affairs, or process. The act of simulating something generally entails identifying certain key characteristics or behaviors of a selected physical or abstract system. And a simulator is the software or hardware tool that performs simulation tasks. When developing a simulator, the non-functional requirements such as modifiability, interoperability, and extendability should be required. However, existing studies about the simulator development focus not on such non-functional requirements but on the methodologies to build the simulation model. In this paper, we suggest the new architectural pattern for the software based simulator in consideration of such non-functional requirements. In order to define the architectural pattern, we identify the essential elements of the simulators, define relationships between them, and design the architectural structure with the elements to accommodate such non-functional requirements. According to the proposed pattern we can solve the simulation problems to combine the various simulation model components. The pattern guarantees modifiability by reconstructing the simulation model, also guarantees interoperability and extendability by adding various interfaces to the simulation model and by keeping the consistent interfacing mechanism between the simulation model components. The suggested architectural pattern can be used as the reference architecture of the simulator systems that will be developed in future.

• Korean Journal of Construction Engineering and Management
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• v.19 no.5
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• pp.70-80
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• 2018

Recently, the construction industry has lively utilized system forms to improve the work productivity and safety of form work, and the beam table form is one of them. However, the beam table form is used limitedly for the construction of buildings where the same beam size is applied to every floor. To make it possible to apply the beam table form to a building where different beam sizes are designed according to the uses of floors, it was analyzed that among the components of the beam table form, the beam bracket, should be able to flexible adjust the size of the beam form only with simple operation. Therefore, the purpose of this study is to propose the conceptual design of "an adjustable beam bracket for beam table form" that allows the adjustment of beam form size with simple operation and has excellent applicability to construction sites as well. In case this study's conceptual design of adjustable beam bracket for beam table form is fabricated into a real thing, it is expected that the beam table form will be applicable to even buildings where different beam sizes are designed according to the uses of floors, thereby contributing to the improvement in the work productivity and safety of form work.

• Journal of the Korea Society of Computer and Information
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• v.7 no.1
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• pp.129-136
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• 2002

Mass production system of most manufacturing companies has been supplying us with various useful needs in life for many years. It leads our life to live in comfortable and prosperous circumstances. And we can consider that the contributions of the mass production system to the reduction of different stratification in community remarkable . However, The needs of many clients in these days are various, different, and segmented. It is undesirable to consider every Product on the same basis anymore. So these new requirements of the customers let manufacturing companies be ready for the new production systems which are able to satisfy all the customers, but differently. In this aspects, the customization system could meet new needs of the customers. As we know, cost increase and flexibility matter for the production are main difficulties for the introduction to mass customization. However, to make arrangements for the mass customization systems of the firms is an indispensible factor for maintaining competitiveness and coping with new needs in the future market. We should remember that customers' needs in market will be changing, segmenting, and diversifying, continuously. For this purpose this thesis is tried for studying strategical approach methods of the mass customization.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.466-476
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• 2019

This study suggested a way to compose a flexible environment capable of meeting the needs of various users from the aged people to challenged people, and ordinary people by applying the concept of universal design. The purpose of this study was to develop a more convenient environment by deriving the best size and color for each subject and constructing a detailed design platform for each module. For this, the concept of universal design as well as the current bathroom designs were examined and various users were analyzed prior to developing the design. A virtual environment was prepared based on the results and its usability was evaluated in two phases with various users including the aged people, challenged people, and ordinary people. As a result, it received quite a favorable evaluation from users, over 90 out of 100 in average, which can be regarded as a proof that it is differentiated from existing bathrooms. This study may lead to the change in the paradigm of bathroom in residential space, development of safer and comfortable domestic environment, and the enhancement of the quality of healthy life through the development of a design platform for each module that provides new experiences to various users. It is hoped that these modular systems are continuously studied not only for bathrooms but also for various residential spaces where people can stay.

• Korean Journal of Ornithology
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• v.25 no.2
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• pp.117-125
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• 2018

The Grey-capped greenfinch (Chloris sinica) is a polytypic species that exhibits complicated geographical variation in morphology. This study provides an intraspecific phylogeographic variability of C. sinica populations in Korea with their morphometric data. The observed morphometric variations were that Ulleung island population was morphologically distinct in bill length and depths as compared to the mainland populations. Phylogenetic relationships among mitochondrial COX1 regions provided evidence for genetic differentiation between Ulleung and mainland populations. However, their genetic distances and nucleotide diversities were very low, highlighting their recent divergence. The needs for additional research is heightened to substantiate if the genetic clines in different localities may arise in C. sinica subspecies, each of which could have different breeding and wintering habitats, distribution patterns, and migration pathways.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.237-243
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• 2019

Floating platforms made of PE (PolyEthylene) are often located in shallows of seas, rivers or lakes. They are widely used for marine pensions, marine pontoons, marine bridges, etc. These products are characterized by good flexibility, recyclability, chemical resistance and weatherability with corrosion resistance. Existing PE floating platforms have a simple structure in which one pipe is fastened to one bracket, but this has limited application, even if a user modifies the arrangement. Therefore, we developed a structure that allows buoyancy pipes of various sizes to be fastened to one bracket and verified the structural safety of the product using the finite element method. From the results of structural analysis for buoyancy pipes of different diameters, the maximum stress ratio was 0.78 compared with allowable criteria of 1.0, which represented sufficient safety for a model with 500 mm diameter pipes. Based on the results of this study, further research to evaluate the structural safety of various floating platforms can be carried out in the further; it will also be necessary to establish related evaluation criteria.