• Elastomers and Composites
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• 제53권3호
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• pp.150-157
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• 2018

Fatigue properties of rubber are one of the most important characteristics in the rubber industry. In this study, the fatigue properties of MREs (magneto-rheological elastomers) based on NR (natural rubber), EPDM (ethylene-propylene diene monomer), and AEM (ethylene/acrylic elastomer) were investigated. For comparison, MREs with a Shore hardness of 60A were prepared. According to the relative results, the fatigue properties of EPDM MRE were the worst. Thus, we investigated methods to improve the fatigue properties of EPDM MRE by varying the carbon black content and curing systems of EPDM as the matrix of the MRE. Dynamic properties were measured using a fatigue tester and an RPA (rubber process analyzer), and the XPS (X-ray photoelectron spectroscopy) was used to analyze the curing system of the EPDM matrix. According to the results, the Payne effect increased and the fatigue resistance decreased as the carbon black content increased. In case of the curing system, the CV (conventional vulcanization) system was superior to the EV (efficient vulcanization) system in terms of the fatigue resistance. This was because the number of flexible bonds in the case of the CV system was higher than that in the case of the EV system. However, the EV system showed excellent mechanical properties because it had many monosulfidic bonds with strong binding energy.

• 한국정밀공학회지
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• 제26권6호
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• pp.68-73
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• 2009

One of the traditional optical methods to monitor a tool is a CCD sensor-based vision system which captures an aspect of the tool in real time. In the case using the CCD sensor, specific lens-modules are necessary to monitor the tool with higher resolution than its pixel size, and a microprocessor is required to attain desired data from captured images. Thus theses additional devices make the entire measurement system complex. Another method is to use a pair of an optical source and a detector per measuring axis. Since the method is based on the intensity modulation, the structure of the measurement system is simper than the CCD sensor-based vision system. However, in the case measuring the three dimensional position of the tool, it is difficult to apply to micro machine-tools because there may not be space to integrate three pairs of an optical source and a detector. In this paper, in order to develop a tool-origin measurement system which is employed in micro machine-tools, the improved method to measure a tool origin in x, y and z axes is introduced. The method is based on the intensity modulation and employs one pair of an optical source radiating divergent beams and a quadrant photodiode to detect a three dimensional position of the tool. This paper presents the measurement models of the proposed tool-origin sensor. The models were verified experimentally The verification results show that the proposed method is possible and the induced models are available for design.

• 공학교육연구
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• 제8권4호
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• pp.5-19
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• 2005

컴퓨터를 활용한 다양한 교육 훈련의 형태는 교육방법과 학습효과에 폭넓은 영향을 미치고 있으며, 산업 및 직업 구조의 변화에 따른 다양한 교육 훈련 형태가 출현하여 학습자 중심의 교육을 가능하게 하고 있다. 인터넷을 활용한 원격교육 및 학습자료 제공 등은 학습자의 수준에 맞는 개별화 교육을 가능하게 하고 있다. 온라인 교육의 경우, 학습자에게 다양한 정보를 즉시, 또는 지속적으로 제공하는 것이 용이하지만, 오프라인 학습의 경우, 출석, 과제, 시험 성적 등의 학업 상태와 관련된 정보를 학습자에 제공하는데 있어서 온라인 방식에 비해 비효율적인 것이 사실이다. 특히, 실습이 많은 전문대학의 공학교육에 있어서 실습결과의 평가에 대한 정보를 제공하는 것이 학업에 많은 영향을 미친다. 본 연구에서는 학업상태에 대한 다양한 정보들을 학습자 및 교수자, 지도교수 등에게 다양한 형태로 제공하는 시스템을 구현하고자 한다. 또한 다른 학습자와 비교하여 본인의 학업 상태를 비교하여 모니터할 수 있도록 하여 학습자의 학습의욕을 높이고 교수자 또는 지도교수가 학생의 학사지도나 진로지도에 활용할 수 있는 정보를 제공할 수 있도록 한다. 과목 담당 교수자의 경우 해당 과목의 전체적인 학업상태 및 개별 학습자의 학업상태 정보를 제공하여 수업의 효율을 높이도록 하고 학습자의 상담 또는 지도교수에게는 학습자가 학습한 모든 정보를 모니터할 수 있도록 하여 학사 지도 및 졸업 후 취업을 위한 기초자료로 활용할 수 있도록 하는 것을 목표로 한다.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2006년도 춘계학술대회
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• pp.294-300
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• 2006

This case study shows constructing the knowledge-based system using a rule-based approach for detecting transactions regarding money laundering in the Korea Financial Intelligence Unit (KoFIU). To better manage the explosive increment of low risk suspicious transactions reporting from financial institutions and to conjugate data converged into the KoFIU from various organizations, the adoption of a knowledge-based system is definitely required. We designed and constructed the knowledge-based system for anti-money laundering by committing experts of each specific financial industry co-worked with a knowledge engineer. The outcome of the knowledge base implementation shows that the knowledge-based system is filtering STRs in the primary analysis step efficiently and so has made great contribution to improve efficiency and effectiveness of the analysis process. It can be said that establishing the foundation of the knowledge base under the entire framework of the knowledge-based system for consideration of knowledge creation and management is indeed valuable.

• Industrial Engineering and Management Systems
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• 제8권1호
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• pp.22-28
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• 2009

We consider facility layout problems, where mn facility units are assigned into mn cells. These cells are arranged into a rectangular pattern with m rows and n columns. In order to solve this cell type facility layout problem, many approximation algorithms with improved local search methods were studied because it was quite difficult to find exact optimum of such problem in case of large size problem. In this paper, new algorithms based on Simulated Annealing (SA) method with two neighborhood generation methods are proposed. The new neighborhood generation method adopts the exchanging operation of facility units in accordance with adjacent preference. For evaluating the performance of the neighborhood generation method, three algorithms, previous SA algorithm with random 2-opt neighborhood generation method, the SA-based algorithm with the new neighborhood generation method (SA1) and the SA-based algorithm with probabilistic selection of random 2-opt and the new neighborhood generation method (SA2), are developed and compared by experiment of solving same example problem. In case of numeric examples with problem type 1 (the optimum layout is given), SA1 algorithm could find excellent layout than other algorithms. However, in case of problem type 2 (random-prepared and optimum-unknown problem), SA2 was excellent more than other algorithms.

• KIEAE Journal
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• 제2권1호
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• pp.11-19
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• 2002

This Study aims to find out the planning aspects and detailed techniques in terms of concept of the Ecological Industrial Parks. It consists of the three parts : Firstly, according to theoretical review, this study gives a definition of the concept of ecological industrial parks. Secondly, it institutes planning aspects of ecological industrial parks based on the main concept. Thirdly, 8 case studies show us analysis of detailed techniques used each planning aspects. Ecological industrial parks mean industrial systems which make energy and substance circulated in order to reduce environmental pollutions inside and outside of park like natural ecosystem. To actualize ecological industrial parks, we have to adopt 3 planning aspects which are energy and substance recycling system, environmentally-friendly site planning based on ecology concept, constructing of ecological production and management. In case study, detailed techniques from each planning aspects are shown in table 8. As a result of case study, detailed techniques about planning of energy and substance recycling system is accommodated most. On the other hand, environmentally-friendly site planning techniques based on ecological concept is used passively. And detailed techniques about constructing of ecological production and management are very various as each cases. Finally, in terms of analysis, this study shows us appliable planning when we develop domestic Ecological industrial parks.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.149-152
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• 2001

In general, the wireless services based on markup language and provided with wired network requires dedicated gateway system. But in this case, the serious problems such as security vulnerabilities, damage of contents are occurred to the application. In this paper, to improve above problems, we designed and implemented the new application named "Interacted Wired St Wireless Student Information System" using J2ME(Java 2 Micro Edition) platform and XML(eXtensible Markup Language) to transmit user data safely and support the system extendibility maintaining data format consistency respectively.pectively.

• 산업경영시스템학회지
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• 제22권52호
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• pp.355-363
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• 1999

As the indirect cost is increasing, ABC(Activity-Based Costing) Method that can distribute the indirect cost to each products is more effectively used. Especially for a Hospital to provide better medical service with patients, It's necessary that build ABC System to provide a regular cost information. This study proposed methodology enabling accurate cost analysis from importing concepts of ABC in a Hospital and presented a Cost Information Table for Work-Time Table and Output Services to calculate ABC.

• 대한한의학원전학회지
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• 제23권2호
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• pp.89-105
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• 2010

Research methodology on Traditional Medicine in East Asia refers to logical thinking system, empirical positivism system and methodology of developing these knowledge systems. Logical thinking system of abstract concepts such as analogy or abduction and positivism system of reasonable explanation such as the five elements and their characteristic theory have been used in various ways empirically or in the form of humanities and knowledge system was developed through parallel structure of empirical positivism and exegetical studies. After the 16th century, evidence was required along with the tradition of putting emphasis on rationality, logicality and empirical positivism and characteristics of medical humanities can be found in emphasizing on medical ethics. Data that can be considered as structural review paper or meta analysis from original data of research on Traditional East Asian Medicine should be evaluated as historical evidence which is equivalent to specialist opinion, descriptive disease research, single case report or case series. Historical evidence based medicine is a research method using Historical evidence to selectively support data that are faithful to traditional theory with higher possibility to be used in future traditional east Asian medicine that links between traditional knowledge and scientific research methodology. Moreover, historical evidence based medicine tries to re-evaluate the value of traditional knowledge and ultimately, guides the direction of development of traditional medicine through scientific rationality based on history and culture.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권10호
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• pp.985-989
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• 2010

미래의 스마트 유비쿼터스 컴퓨팅 기반 시스템은 사용자들과 상호작용을 통해 적절한 서비스를 제공할 것 이다. 사용자 요구(Needs)에 맞는 서비스를 제공하기 위해서는 기존의 개발자 중심의 개발보다 사용자의 요구를 반영하는 사용자 중심의 시스템 개발이 필요하다. 이를 위해 이전 논문에서는 사용자 행위 분석 기반 요구 추출방법(User Behavior Analysis Based Needs Extraction Method)을 제안하였다[1]. 본 논문에서는 추출된 사용자의 요구사항을 Fillmore의 Case Grammar을 이용하여 객체 추출 및 모델링 방법을 제안한다.