• Agricultural and Biosystems Engineering
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• 제1권1호
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• pp.49-53
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• 2000

A magnet assembly is a critical element of a nuclear magnetic resonance(NMR) based sensor. Magnetic flux density and homogeneity are essential to its optimum performance. Geometry and magnet material properties determine the magnetic flux density and homogeneity of the assembly. This study was carried out to develop the design for a magnet assembly. A 2-D finite element model for the magnetic assembly was developed using ANSYS and evaluated the effects of adding shimming frames and steel bars in the corners of the rectangular steel cover which surrounded the magnet. The assembly was manufactured and evaluated. According to the ANSYS model, modified pole frames increased magnetic flux density by 8.3% and increased homogeneity by 83%. Addition of steel bars in the corners increased the magnetic flux density by 1%, and improved homogeneity up to three times. The difference between simulated and measured magnetic flux densities at the center point of the air gap was within 2.4%.

• 산업공학
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• 제17권2호
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• pp.208-217
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• 2004

This paper deals with a process planning problem in the flexible assembly system (FAS). The problem is to assign assembly tasks to stations with limited working space and to determine assembly routing with the objective of minimizing transfer time of the products among stations, while satisfying precedence relations among the tasks and upper-bound workload constraints for each station. In the process planning of FAS, the optimality of assembly routing depends on tasks loading. The integration of tasks loading and assembly routing is therefore important for an efficient utilization of FAS. To solve the integrated problem at the same time, in this paper we propose a new method using an artificial intelligent search technique, named 2-leveled symbiotic evolutionary algorithm. Through computational experiments, the performance of the proposed algorithm is compared with those of a traditional evolutionary algorithm and a symbiotic evolutionary algorithm. The experimental results show that the proposed algorithm outperforms the algorithms compared.

• 한국전산구조공학회논문집
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• 제35권5호
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• pp.259-266
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• 2022

본 논문에서는 프리팹 구조물의 품질관리를 위한 딥러닝 및 비전센서 기반의 조립 성능 평가 모델을 개발하였다. 조립부 검출을 위해 인코더-디코더 형식의 네트워크와 수용 영역 블록 합성곱 모듈을 적용한 딥러닝 모델을 사용하였다. 검출된 조립부 영역 내의 볼트홀을 검출하고, 볼트홀의 위치 값을 산정하여 k-근접 이웃 기반 모델을 사용하여 조립 품질을 평가하였다. 제안된 기법의 성능을 검증하기 위해 조립부 모형을 3D 프린팅을 이용하여 제작하여 조립부 검출 및 조립 성능 예측 모델의 성능을 검증하였다. 성능 검증 결과 높은 정밀도로 조립부를 검출하였으며, 검출된 조립부내의 볼트홀의 위치를 바탕으로 프리팹 구조물의 조립 성능을 5% 이하의 판별 오차로 평가할 수 있음을 확인하였다.

• International Journal of Control, Automation, and Systems
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• 제5권2호
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• pp.192-199
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• 2007

This paper proposes a new printed circuit board (PCB) assembly planning method for multi-head surface mounters. We present an integer programming formulation for the optimization problem, and propose a heuristic method to solve the large NP-complete problem within a reasonable time. A dynamic programming technique is then applied to the feeder arrangement optimization and placement sequence optimization to reduce the overall assembly time. Comparative simulation results are finally presented to verify the usefulness of the proposed method.

• 한국문헌정보학회지
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• 제47권4호
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• pp.25-48
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• 2013

본 연구는 국회기록정보 온라인 서비스의 발전 방안을 제시하는 데 목적을 둔다. 이를 위해 기록정보서비스 관련 선행연구를 분석하고, 국회기록정보서비스의 현황을 파악한다. 이를 통해, '포괄적 기록정보서비스의 부재', '대국민 서비스 창구의 부재', '콘텐츠의 부재' 등 국회기록정보서비스의 문제점을 파악한다. 사례 연구로서 미국과 영국 입법기록관리기관의 온라인 서비스를 분석하고, 그 유형을 검색지원 서비스, 부가 콘텐츠 서비스, 확장 서비스로 구분하여 각각의 구체적 사례를 살펴본다. 해외사례 분석에서 도출한 시사점을 바탕으로, 결론에 갈음하여, 국회기록 포털의 구성, 포괄적 검색지원 서비스의 제공, 맞춤형 부가 콘텐츠의 개발, 웹 아카이브 서비스 제공, 조직적 확장 서비스의 제공 등 5가지 영역에서의 국회기록정보서비스 발전 방안을 제시한다.

• 대한한의학회지
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• 제31권1호
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• pp.112-121
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• 2010

Objectives: The aim of this study was to reflect upon the process of the legislation of the National Medical Services Law for traditional Korean medicine practitioners (TKM practitioners), especially at the Assembly plenary session of 1951. Methods: Various primary sources related to the legislation were examined, especially those in National Assembly Records and newspapers. Results: In 1950, the National Assembly wanted to establish the National Medical Services Law (國民醫療法) replacing the colonial medical services law (朝鮮醫療令), but it ended in failure. So in 1951, the National Assembly tried again. First, legislator Han Gukwon (韓國源), with 83 other legislators, introduced a bill for the new national health care system. The Society and Health (社會保健委員會) and the Legislation and Judiciary subcommittees (法制司法委員會) deliberated on this bill, and each proposed an amendment to the National Assembly. In the process of careful deliberation of these three proposals, the Ministry of Health and legislator Kim Ikgi (金翼基) each came up with a further amendment. Ultimately, Kim Ikgi's amendment was accepted by the National Assembly. According to his proposal, TKM practitioners were titled 'Hanuisa (漢醫師)', and the medical office name of TKM practitioners became 'Hanuiwon (漢醫院)'. Conclusions: The National Medical Services Law passed in 1951 was the beginning of the unique dual national medical license system of Korea. It recognized Western medicine and TKM practitioners equally under the national license system.

• 품질경영학회지
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• 제45권4호
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• pp.829-846
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• 2017

Purpose: This paper compares the effectiveness of typical selective assembly criteria and suggests the most promising one. Based on the result of a computer simulation, the key issues of selective assembly are examined and the best criterion is recommended from the effectiveness perspective. Methods: Using JAVA program, production of ten thousand units for each pair of components are simulated for selective assembly of the two types. And the number of mismatching and the fraction nonconforming for each criterion are determined. Results: The best match criterion appeared to be most promising from the perspectives of both mismatching and nonconforming problems. Its effectiveness appears to be also good even when the precision of one component is different from that of the other. Conclusion: For designing an optimal method for selective assembly, the best match criterion is recommendable as the base criterion.

• Macromolecular Research
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• 제16권4호
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• pp.267-292
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• 2008

Block copolymers that two or more polymer chains are covalently linked have drawn much attention due to self-assembly into nanometer-sized morphology such as lamellae, cylinders, spheres, and gyroids. In this article, we first summarize the phase behavior of block copolymers in bulk and thin films and some applications for new functional nanomaterials. Then, future perspectives on block copolymers are described.

• Current Optics and Photonics
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• 제3권5호
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• pp.429-437
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• 2019

Temperature adaptability is an important metric for evaluating the performance of an optical system. The temperature characteristics of the optical system are closely related to the material and shape of its lens. In this paper, we establish a mathematical model relating the temperature characteristics to the shape and material of the lens. Then a novel assembly structure that can solve the lens constraint and positioning problem is proposed. From those basics, the correctness of the theoretical model and the effectiveness of the assembly structure are verified through simulated analysis of the imaging quality of the optical system, whose operating temperature range is $-60{\sim}100^{\circ}C$.

• 품질경영학회지
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• 제49권1호
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• pp.17-29
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• 2021

Purpose: During 2015-2019, the average amount of political donation to the national assembly members in Korea was 1,000 won per person. Despite its benefits such as receiving tax credits, the donation system has not been actively practiced. This paper aims to promote political donations by suggesting a recommendation system of national assembly members by analysing the bills they proposed. Methods: In this paper, we propose a recommendation system based on two aspects: how similar the newly proposed or ammended bills are to the sponsors' interest (similarity index) and how much effort national assembly members put into those bills (intensity index). More than 25,000 bills were used to measure the recommendation quality index consisted with both the similarity and the intensity indices. Word2vec was used to calculate the similarity index of the bills proposed by the national assembly member to the sponsor's interest. The intensity index is calculated by diving the number of newly proposed or entirely revised bills with the number of senators who took part in those bills. Subsequently, we multiply the similarity index by the intensity index to obtain the recommendation quality index that can assist sponsors to identify potential assembly members for their donation. Results: We apply the proposed recommendation system to personas for illustration. The recommendation system showed an average f1 score about 0.69. The analysis results provide insights in recommendation for donation. Conclusion: n this study, the recommendation system was proposed to promote a political donation for national assembly members by creating the recommendation quality index based on the similarity and the intensity indices. We expect that the system presented in this paper will lower user barriers to political information, thereby boosting political sponsorship and increasing political participation.