• 천문학회보
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• 제45권1호
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• pp.57.3-57.3
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• 2020

The chemical and kinematic properties of stars in the Galactic halo provide crucial information on the origin of the Galactic halo as well as the assembly history of the Milky Way. In this study, we present metallicity distribution functions (MDFs) in different regions of the Galactic halo as well as the kinematic characteristics in each region. The different MDFs and kinematic properties of stars in investigated regions allow us to associate them with the possible progenitor dwarf galaxies discovered to date; hence the assembly history of the Galactic halo.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권4호
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• pp.450-457
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• 2018

The determination of assembly sequence in general mechanical assemblies plays an important role in terms of manufacturing cost, duration and quality. In the production of ships and offshore plants, the consideration of productivity factors and welding deformation is crucial in determining the optimal assembly sequence. In shipbuilding and offshore industries, most assembly sequence planning has been done according to engineers' decisions based on extensive experience. This may result in error-prone planning and sub-optimal sequence, especially when dealing with unfamiliar block assemblies composed of dozens of parts. This paper presents an assembly sequence planning method for block assemblies. The proposed method basically considers geometric characteristics of blocks to determine feasible assembly sequences, as well as assembly process and productivity factors. Then the assembly sequence with minimal welding deformation is selected based on simplified welding distortion analysis. The method is validated using an asymmetric assembly model and the results indicate that it is capable of generating an optimal assembly sequence.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.106-113
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• 2008

The goal of crashworthiness is an optimized vehicle structure that can absorb the crash energy by controlled vehicle deformations while maintaining adequate space so that the residual crash energy can be managed by the restraint systems to minimize crash loads transfer to the vehicle occupants. Front side assembly is one of the most important energy absorbing components in relating to the crashworthiness design of vehicle. The structure and shape of the front side assemblies are different depending on auto-makers and size of vehicles. Thus, it is not easy to grab an insight on designer's intention when you glance at a new front side member without experiences. In this paper, we have performed the explicit nonlinear dynamic finite element analysis on the front side assembly of a passenger car to investigate the effect of thickness distribution of the front side assembly on the collapse shape, which is important in the aspect of controlling deformation to maintain adequate space, from the viewpoint of reverse engineering. To do this, we have performed crash FE analysis for the assembly by varying the thickness distribution of the assembly.

• 시큐리티연구
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• 제50호
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• pp.61-87
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• 2017

국회는 민의에 제일 먼저 귀 기울이는 헌법기관으로서 국민의 고객만족도를 보다 높이기 위하여 국회의 주차서비스를 향상해야 함과 동시에 국회주차장을 이용하는 시민과 자동차에 대하여 보안성을 보다 높일 수 있도록 해야 한다. 이러한 인식 하에 본 연구는 첫째, 현재 관리위탁 중인 국회둔치주차장을 범죄예방디자인(CPTED) 관점에서 검토하고, '영역성'의 확보를 위한 울타리 설치 및 보강작업이 필요함과 동시에 '접근통제'를 위해 출입구에 사면촬영카메라 운영과 출입금지 경고판의 설치를 제시하였다. 둘째, 국회둔치주차장 CCTV 보안시스템의 운영을 국회안전상황실과의 통합(접속)하도록 권고하고, CCTV 카메라의 성능을 2M 이상으로 성능을 높이도록 하였다. 또한 녹화방식도 NVR 방식으로 전환하여 향후 IP카메라 등의 적용에 대비하도록 하였으며, 현장의 실사결과를 토대로 3곳의 CCTV 신규 설치장소를 적시하였다. 셋째, 주차장 관리 및 운영에 있어서 무인화장비 도입을 통한 주차요금징수 및 관리체제 도입을 권고하였다. 이로써 주차장 관리방식을 24시간 운영방식으로 전환하여 보다 전문화된 주차서비스를 제공할 수 있도록 해법을 제시하였다.

• 대한산업공학회지
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• 제27권1호
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• pp.103-110
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• 2001

The aim of this paper is the implementation of high assembly productivity through product redesign. The product and process are analyzed by influencing factors for based data of the product redesign. And then, the weak assembly processes are analyzed by weak influencing factors. By this information about product and process, the score of weakness of influencing factors extracts the redesign rules and principles. The sequences of processes are changed according to the product redesign, and they are evaluated using the line efficiency and smoothness index.

• 한국염색가공학회지
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• 제18권1호
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• pp.28-32
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• 2006

A multi-layer of the dye, natural colorant Berberine, was successfully developed by the self-assembly deposition from water-soluble cationic dye(Berberine chloride) and anionic polyelectrolyte PSS(Polysodium 4-styrenesulfonate) in aqueous solution via electrostatic attraction. The corresponding results on multi-layer were characterized by UV-Vis absorbance measurements. The growth of multi-layer formed by the sequential interaction was also determined. The findings measured by UV-Vis spectrophotometer showed that the bilayer deposition characteristic was linear and highly reproducible from layer to layer.

• Nuclear Engineering and Technology
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• 제40권6호
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• pp.439-450
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• 2008

The KSTAR device succeeded in first plasma generation on $13^{th}$ June of 2008 through comprehensive system test and commissioning. Among various kinds of the key factors that decisively affected the project, success in the construction and assembly of the major tokamak structure was most important one. Every engineering aspects of each structure were finally confirmed in the integrated commissioning period, and there were no severe troubles and failures prevented the KSTAR device from operating during the commissioning and the first plasma experiments. As a result, all of the experiences and technologies achieved through the KSTAR construction process are expected to be important fundamentals for future construction projects of superconducting fusion devices. This paper summarizes key engineering features of the major structures and of the machine assembly.

• 동의생리병리학회지
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• 제26권5호
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• pp.588-598
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• 2012

The aim of this study is to reflect on the issues of the National Medical Services Law for Korean medicine practitioners (KM practitioners) in Korea, especially those discussed at the Assembly plenary session in 1951. In 1951, 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). Consequently the National Assembly passed the law establishing the license level of KM practitioners equal to that of Western practitioners. But the progress of establishing the law was not easy. There was much dispute over the KM practitioners system amongst the legislators at the Assembly plenary session in 1951. One of the main dispute was about setting the license level of KM practitioners. There were two main positions. One insisted that the license level of KM practitioners should be equal to that of Western practitioners. They had many reasons to support their contended point. From a historical, social, economical, medical and institutional point of view, they argued that the people had needed the KM and thus the new founded Korea had to reflect this situation. The other insisted that the license level of KM practitioners should be below that of Western practitioners. The reason was mainly that the KM was not scientific. This study concludes that the argument of the former was superior to the latter in quantity and quality.

• 대한지리학회지
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• 제48권3호
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• pp.387-401
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• 2013

우리나라 선거구 획정은 인구의 증감이나 행정구역의 변경뿐만 아니라 지극히 정치적인 의도와 목적을 가지고 이루어져 선거결과에 중대한 영향을 미친다. 이 논문은 선거구 구획의 실행 측면에 초점을 맞추어 선거구 구획을 위한 대안적 방법을 제시하는 데 초점을 맞추고 있다. 즉 과정에서 자의성이 개입될 수 있는 부분에 절차적이고 객관적인 선거구 획정 방법론을 제시하고자 한다. 이를 위하여 선거구 획정기준(인구등가성, 연속성, 공간적 조밀성)을 준수하는 공간 최적화 모델을 고안하고 제19대 선거구 획정결과에서 논란이 되었던 용인시에 적용하여 그 가능성을 평가한다. 모델의 분석 결과는 정치적 고려나 임의적 개입 없이 기저의 데이터만으로 기준을 만족하는 선거구를 확정할 수 있음을 보여주었다. 특히, 모델에 의해서 도출된 선거구는 기존 선거구에 비하여 인구등가성을 향상시켰다.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.799-804
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• 2008

An amphiphilic diacetylene compound was deposited on the surface of nano sized magnetite particles ($Fe_3O_4$) using a self-assembly method. The diacetylene molecular assembly formed on the surface of nanoparticle was subjected to photopolymerization. This resulted in the formation of a polymeric assembly on the surface of the nanoparticles in which the adjacent diacetylene molecules were connected through conjugated covalent networks. The presence of immobilized polymer species on the surface of nanoparticles is expected to protect them from agglomeration and ripening, thereby stabilizing their physical properties. In this work, $Fe_3O_4$ nanoparticles were prepared by chemical coprecipitation method and the diacetylene molecule 10,12- pentacosadiynoic acid (PCDA) was anchored to the surface of $Fe_3O_4$ nanoparticles through its carboxylate head group. Irradiation of UV light on the nanoparticles containing immobilized diacetylenes resulted in the formation of a polymeric assembly. Presence of diacetylene molecules on the surface of nanoparticles was confirmed by X-ray photoelectron spectroscopy and FT-IR measurements. Photopolymerization of the diacetylene assembly was detected by UV-Visible spectroscopy. Magnetic properties of the nanoparticles coated with polymeric assembly were investigated with SQUID and magnetic hysteresis showed superparamagnetic behaviors. The results put forward a simple and effective method for achieving polymer coating on the surface of magnetic nanoparticle.