• Journal of the Korea Society for Simulation
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• v.18 no.2
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• pp.65-75
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• 2009

The semiconductor manufacturing process normally includes a great number of complex sequential steps those are related with various types of equipment. Such equipments are installed with the mixed patterns of serial or parallel structures while considering a number of engineering or environmental factors at the same time. It is thus extremely difficult to change the layout after installation due to expensive costs and other related factors. Because of these reasons, a new investment or layout change, which is usually caused by the production policy such as product mix or production quantity, must be carefully considered. This case study introduces a simulation conducted in a semiconductor parts production company which produces the Board on Chip (BOC)-type of packaging substrate and has plans to change the facility layout. For this study, we used $QUEST^{(R)}$ for simulation modeling and evaluated various strategies which may cause layout changes. Further, the Analytic Hierarchy Process (AHP) is applied to select the best strategy from several alternatives with multiple decision criteria.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.145-145
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• 2015

처음 유기물의 인광 발견 이후 Host-dopant 시스템을 이용하여 Emission layer(EML)을 Co-deopsition 하는 방법으로 주로 인광 유기 발광 다이오드를 제작 하였다. [1] co-deposition을 이용해 만든 유기 발광 다이오드에 많은 장점이 있지만, 반대로 소자를 제작하는데 있어서는 많은 문제점을 가지고 있다. [2-4] 이러한 문제점을 개선하기 위하여 co-deposition 대신 non-doped Multi Quantum Well(MQW) 구조를 사용하여 doping 하지 않는 방법을 이용하는 논문들이 보고 되고 있다. Hole, electron, exciton이 MQW 구조를 지나면서, dopant well 안에 갇히게 되고, 그 안에서 다른 layer 간에 energy transfer와, hole-electron leakage가 줄어 들어, 더 효율적인 유기 발광 다이오드를 만들 수 있게 된다. [5-7] 이 연구에서는 CBP를 Potential Barrier로 사용하고, Ir(ppy)3 (Green dopant), Ir(btp)2 (Red dopant) 를 각각 Potential Well로 사용하였고, 두께는 CBP 9nm, dopant 1nm로 하였다. 이러한 소자를 만들고 dopant를 3개의 well에 적당히 배치하여, 각 well에서의 실험적인 발광 량 과, EML 안에서의 발광 mechanism 그리고 각 potential barrier를 줄여가며 dexter, forster에 의한 energy transfer에 대하여 알 수 있었다.

• Journal of the Daesoon Academy of Sciences
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• v.16
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• pp.265-304
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• 2003

장례의식은 불교에서 가장 중요한 정기적인 의식들 중에 하나이다. 이러한 의식은 수도자나 죽은 사람들을 위해서 행해지고 있다. 그렇다고 장례의식의 목적이 죽은 사람들만을 위한 것이 아니라 근원적으로는 'saṃsāra'의 윤회로부터 완전한 해방을 구하는 모습을 의미한다. 티벳불교에서의 죽음은 두 가지를 의미를 인식한다. 하나는 열반으로 입적하는 것으로 다섯 가지에 완전히 융해되는 것을 뜻한다. 이러한 죽음은 더 이상의 '태어남'이 없다. 열반의 경지는 카르마 안에서 융해 되거나 평화를 얻은 경지인 것이다. 또 하나의 죽음은 카르마의 법칙에 의해서 통제 되거나 하나의 영혼이 열반 안으로 들어가기 전까지 순환적인 주기 안에서 지속적으로 반복되는 것이다. 카르마는 불교의 관례를 통해서 카르마의 힘은 없어질 수 있다고 할지라도 근본적으로 외부적인 간섭을 수행하지는 않는다. 즉 불교의 이념들은 각자의 노력을 통해 해방을 얻는 것을 가르치고 있다. 하지만 카르마의 경로가 식별하기 어려워 제의식의 효과나 수행의식을 통해 알아 볼 수밖에 없다. 여기서는 티벳불교에서 죽은 후의 몸을 적절히 배치하는 방법을 얻는 제의식이나 축제에 관심을 갖는 것이 아니라 이를 통한 실질적이고 복합적인 힘, 그리고 카르마적 흐름을 바꾸거나 심지어 없애버릴 수 있는 의식에 관심을 갖고자 한다.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.167-172
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• 2016

Commercial analysis has been used for a lot of reasons such as improving the distribution structure, operational cost savings. However, existing commercial assay system is mostly flow through the analysis of the population and the environment around the store. Therefore, in this paper, we design a path weighted data analysis system for efficient product arrangement. It is not applying the analysis method of the existing commercial sales center but the data analysis system applying the weight to the form of customers' paths in a store. In conjunction with the existing POS system, it provides effective product placement in department stores, such as supermarkets, convenience stores. To this end, a system that maximizes efficiency of product placement in stores, receiving path data, converting them into statistics data that apply the weight, and printing out them into a visualized monitering system for the manager to see was designed.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.11
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• pp.1296-1304
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• 1999

본 논문은 다수의 고객들에게 실시간 재생 서비스를 제공하는 주문형 비디오 서버에서 데이타 검색의 효율을 높이기 위한 저장 시스템의 구조와 그에 따른 배치 정책을 제안한다. 주문형 비디오 저장 서버에서 동시에 보다 많은 고객들에게 그들이 원하는 서비스를 제공하기 위해서는 여러 분야에서의 다양한 정책들이 고려될 수 있으나, 특히 저장 매체들을 어떤 구조로 구성하고 여기에 비디오 객체들을 어떻게 배치할 것인가는 검색 효율과 직접 관계되는 중요한 문제이다. 본 논문에서는 디스크 배열 형태로 구성된 저장 시스템을 디스크 성능을 고려하여 재구성하고, 비디오 객체들을 저장할 때 저장하고자 하는 데이타의 특성들과 저장 구조를 함께 고려하여 검색 효율을 극대화할 수 있는 배치 방법을 제안한다. 마지막으로 제안된 정책의 검색 효율을 검증하기 위해 다양한 실험을 통하여 기존의 배치 정책들과 비교하고 성능을 평가한다.Abstract In this paper, we propose the structure of storage system and a placement policy to provide many clients with real-time playback services efficiently in VOD(video-on-demand) server. Though policies in various areas being considered to provide more clients with services of degree requested by them simultaneously in VOD storage server, it is important how to construct storage media and to place video objects on it for retrieval efficiency. In this paper, we reorganize a large disk array with disks performance and place video objects using the placement policy considering both characteristics of video data and the structure of storage system for maximizing retrieval efficiency. Lastly, we simulate the proposed policy and conventional policies through various environments, compare our policy with others n evaluate the performance of our policy.

• Education of Primary School Mathematics
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• v.20 no.4
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• pp.305-319
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• 2017

In the process of finding the triangle height, 26 students in the 6th grade were surveyed to understand the students' triangle height through the eye movement data and to investigate the cognitive load of the students. As a result, the correctness rate of the pre-test was significantly increased in the post-test, and the frequency and retention of gaze data were smaller in the post-test than in the AOI of each question. The Participants's subjective cognitive load indicated that it was more difficult to understand the concept of rotated triangles compared with upright triangles that were parallel to the ground. More frequent and more retentions in the eye-tracking data were detected in the right triangles and acute triangles by rotating configuration. Eye movement data show that eye tracking technology can provide an objective measure of students' cognitive load for feedback on instructional design.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1B
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• pp.106-116
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• 2010

Sensor deployment makes an effect on not only covering of the interesting area but also reliable data acquisition and efficient resource management of sensor, so that sensors must be deployed at their better place. In traditional static wireless sensor networks, however, it is impossible to deploy the sensors manually when they are distributed in unexploited, hostile, or disaster areas. Therefore, if each sensor has locomotion capability, it can re-deploy itself using the location information of neighbor sensors. In our previous study, we showed that moving sensors to the centroids of their Voronoi polygon is efficient for extending the coverage area. In this paper, we present an improved potential-field-based sensor self-deployment scheme by combining the centroid of Voronoi polygon with the traditional potential-field scheme. Simulation results show that our scheme can achieve higher coverage in shorter time and less movement than the traditional potential-field scheme.

• Journal of Digital Contents Society
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• v.19 no.9
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• pp.1631-1639
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• 2018

VR 360 video contents requires new visual language research in that the viewer inevitably makes partial appreciation unlike traditional video contents. In this study, we paid attention to the fact that arrangement of events and background elements in the 360-degree extended background of VR 360 video contents will play a major role in guiding the audience. Therefore, this study focuses on the arrangement of events and background elements from a narrative point of view, and analyzed the aspects of VR 360 video contents cases.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.413-420
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• 2004

The Busan New harbor will be opened by 2011, after which it is expected that the marine traffic volume around this area would Increase significantly and that very large ships such as 12,000 TEU container ships would come into the port. Therefore, it is necessary to build a new ships' routeing by considering these factors. In this paper, environmental circumstances, marine traffics, and the preceding studies have been reviewed and ships' routeing is proposed through experts' opinions and Delphi technique. For the purpose of validation, the proposed ships' routeings are reviewed by several guidelines on the ships' routeing and through simulation studies.

• Journal of the Korea Society for Simulation
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• v.15 no.4
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• pp.137-142
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• 2006

D/In modern production industries, computer aided systems have been improving the efficiency and convenience of the various stages of work. However. as the complexity of computerized production systems increases, various techniques are still necessary. The problem we addressed occurs in computer systems that automatically make manufacturing process plans in the metal grating manufacturing industry. In the grating layout design, the key to saving the manufacturing cost is to find a design with the minimal number of cutting operations. The proposed genetic algorithm explores the feasible alternatives within the space until an optimal solution is obtained.