• Membrane and Water Treatment
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• 제8권5호
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• pp.411-421
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• 2017

Forward osmosis (FO) is an emerging technology which can possibly make the desalination process more cost and energy efficient. One of the major factors impeding its growth is the lack of an appropriate draw solute. The present study deals with the identification of potential draw solutes, and rank them. The comparison was carried out among ten draw solutes on the basis of four main parameters namely; water flux, reverse salt diffusion, flux recovery and cost. Each draw solute was given three 24 hour runs; corresponding to three different concentrations; and their flux and reverse salt diffusion values were calculated. A fresh membrane was used every time except for the fourth time which was the flux recovery experiment conducted for the lowest concentration and the change of flux and reverse salt diffusion values from the initial run was noted. The organic solutes inspected were urea and tartaric acid which showed appreciable values in other parameters viz. reverse salt diffusion, flux recovery and cost although they generated a lower flux. They ranked 5th and 8th respectively. All the experimented draw solutes were ranked based on their values corresponding to each of the four main parameters chosen for comparison and Ammonium sulfate was found to be the best draw solute.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.510-514
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• 2002

Power Quality and reliability are becoming important issues for critical and sensitive loads. The recent growth in the use of impactive and nonlinear loads has caused many power quality problems such as voltage flicks, harmonics and unbalances, which may cause the modem automatic devices to fail, misoperate, or shut down. This paper deals with 7-Level H-Bridge Line-Interactive Dynamic Voltage Restorer (LIDVR) system. It has the power factor near to unity under normal source voltage, can compensate the harmonic current of the load and instant interruption, and has the fast response. Currently, most of the DVR design studies are based on the assumption of the balanced three-phase system. But, actually line fault occurred $1{\phi}\;{sag}\;or\;2{\phi}$ sag. Hence, proposed new control scheme compensate asymmetry input voltage. Finally, simulation results verify the proposed 7-Level H-Bridge LIDVR system.

• 한국산림과학회지
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• 제94권5호통권162호
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• pp.291-301
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• 2005

Robinia pseudoacacia is one of most widely cultivated exotic species in Bulgaria. The total area of black locust plantations amounts to 2.9% of the total forest area of the country. 15.34% of the plantations are of management afforestations category, where the priority is given to timber production. They have been created on rich and moisture soils, which are the most appropriate for the species in order to achieve its biological potentials of high productivity. The rest of the available plantations in the country are planted on poorer and drier soils up to 600~800 m altitude. The high adaptive ability of the species to unsuitable environmental conditions as well as the high sprout potential was used for their creation. These stands are mainly done with the aim to protect and ameliorate damaged environments and production of small-size timber and fire woods. They are cultivated until 15-20 years and are revived by sprouts. Therefore the management goals searched, 45.69% of those forests are low productive and 38.97% with average productiveness. The present report deals with growth and productivity capacity of black locust plantations; production of sowing materials; production of reproductive and vegetative saplings for afforestation; the technological aspects of afforestation works; the management and use of black locust plantations as well as some more important diseases and pests affecting the species. The report is entirely based on Bulgarian scientific research works and experience with the Robinia preudoacacia. Recommendations for optimizing the use of species are given.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권7호
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• pp.400-405
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• 2000

In order to improve the reliability of XLPE cables, it is necessary to understand the mechanism of electrical and water tree degradation. Especially, electrical tree initiation and propagation are important in XLPE cable insulation. This paper deals with the changes of electrical properties of XLPE cable insulation with electrical tree degradation. To understand the electrical properties of XLPE insulation, specimens were prepared by 22.9kV distribution cable and made in a type of block. Ogura needles having tip radius of 10${\mu}{\textrm}{m}$ were inserted into each block pieces. AC voltages of 8kV, 10kV and 12kV at 60Hz were applied to needle. We investigated the relationship between electrical properties(PD quantity, tan$\delta$ and DC current) and the growth of electrical tree. The electrical properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed.

• 대한가정학회지
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• 제44권8호
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• pp.143-150
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• 2006

Life Science or Home Economics has its own history of scholarship. In South Korea, the School of Home Economics was regarded as the best school of 'producing best brides' in the early stage of its academic history. Since the 1980s when South Korean society went through a speedy economic growth with development of culture and service industry, the school was transformed to educating highly professional career women in the field of industry which deals with everyday lives. As an applied science in nature, the school of Home Economics has had a heavy emphasis on engineering the familial and social life. It also has heavily depended on imported theories and statistical researches. In the crisis of familial and social disintergration, the role of School of Home Economics needs to be redefined. Reexamination of the premises of Home Economics and methodology is necessary. Decolonializaton of the scholarship in the changed condition of global capitalism is particularly urgent in the late modern era of reflexion.

• 한국게임학회 논문지
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• 제17권4호
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• pp.101-108
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• 2017

본 연구는 현재 크게 성장하고 있는 AI(인공지능)이 어떻게 게임에서 적용되고 발전되고 있는지에 대해서 탐구한다. 오늘 날 대중들이 가장 즐겨하고 있는 게임 중 하나인 포커(Poker)에서의 인공지능의 현실을 분석하고 논리적인 발전방향을 제시한다. 구체적으로, 본 연구는 다양한 포커 게임들 중 전 세계적으로 인기가 있는 종류인 텍사스 홀덤(Texas Hold'em)을 중심으로, 이 게임에 적용 되었던 2가지 AI인 Libratus와 DeepStack을 다루도록 한다. 여러 뉴스 기사 인공지능의 성장을 보고 하였으나, 본 연구는 정확히 어떻게 그리고 왜 인공 지능이 포커 게임에서 적용이 되는지, 또한 무엇이 진짜 문제이고 발전 방향인지에 대해서 입체적으로 논의한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권5호
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• pp.204-212
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• 2002

In order to improve the reliability of high voltage rotating machines, it is necessary to understand the breakdown mechanism of stator windings. Especially partial discharge(PD) inception and growth are important in stator winding insulation. Recently, many research on the diagnosis of stator winding insulation for large rotating machines have been developed since the 1970s. Capacitive couplers have been the most widely used sensor for on-line partial discharge detection in rotating machines. This paper deals with the electrical on-line monitor characteristics of ceramic coupler(CC) which has been developed to continuously measure the PD activity in operating high voltage motor stator windings on site. We investigated the electrical characteristics(PD quantity, breakdown voltage and frequency response) to develop CC. This paper presents frequency characteristics and laboratory test result to compare conventional 80([F] epoxy-mica coupler(EMC) and 105[pF] CC for PD measurement with 6.6㎸ model stator windings.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.141-148
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• 2009

The purpose of this paper is to propose a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. Green roof system is considered to be an important subject in construction industry for green growth project. At the same time, we have to consider the counterplan for protection the damage of waterproofing layer and concrete substrate from the penetration of plant root. But many kinds of materials for protection from root penetration are using in construction field. But the performance of those materials is not clear, and there is not test methods for the evaluation of performance. So in this paper, based on the research results of 4 institutes during four years and foreign cases, we made a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. This test method deals with about environmental condition of laboratory, experimental facilities, kinds of plant, specimen of test, management methods, evaluation duration and documents, etc.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2005년도 추계학술대회 논문집
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• pp.205-209
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• 2005

A traditional settlement, in a long history establishment, is appeared to be configured of the people and their life in the areas. This is, a positive aspects, compared to most of the city in these day which is monotonous aspects. The purpose of this research deals what is the formation process and spatial character in urban settlement of Naju city, and how to applicate in a modern city context. For the research goals, it analyse an old Naju Castle area, transformation of the land use through the cadastral survey, and spatial character through step by step in chronical approach. The process of change can be seen in the devide pattern in a lot, formation and extension of a private road, and formation and change of the road; This shows how to changes traditional settlement in a old urban areas of Naju city. A now road system in old area, as a conflict, push the change of the spatial organization, and the balance of the identity of a traditional settlement and a new change as a convenient needs, it is a key point to get ideal settlement.

• 한국산학기술학회논문지
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• 제9권3호
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• pp.831-839
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• 2008

전 세계적으로 철강산업의 중요성은 높아지고 있으며, 철강수요 역시 증가하고 있는 추세이다. 한국 철강산업의 철강생산량은 전 세계에서 5위를 차지하고 있어 국내에서는 철강산업에 대한 관심이 커져가고 있다. 또한 철강산업은 국내에서 경제성장을 이끌어 온 국가기간산업중의 하나이다. 이에 본 연구에서는 산업연관분석을 이용하여 철강산업이 국민경제에 미치는 파급효과들을 시계열로 분석하여 보고자 한다. 먼저 수요유도형 모형을 이용하여 생산유발효과, 부가가치 유발효과 그리고 취업유발효과를 살펴 볼 것이며, 아울러 공급유도형 모형 및 레온티에프 가격모형을 적용하여 철강산업의 공급지장효과와 물가파급효과에 대하여 살펴보고자 한다.