• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.87.1-87.1
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• 2011

The residential Fuel Cell system has high efficiency of 85% with transferring natural gas to electrical power and heat, directly and it is a friendly environmental new technology in that $CO_2$ emission can reduce 40% compared with conventional power generator and boiler. The residential fuel cell system consists of two main parts which have electrical and hot storage units. The electrical unit contains a fuel processor, a stack, an inverter, a control unit and balance of plant(BOP), and the cogeneration unit has heat exchanger, hot water tank, and auxiliaries. 5kW class fuel process was developed and tested from 2009, it was evaluated for long-term durability and reliability test including with improvement in optimal operation logic. Stack development was crried out through improvement of design and evaluation protocol. Development of system controller was successfully accomplished through strenuous efforts and original control logic was optimized in 5kW class PEMFC system. In addition, we have been focused on development of system process and assembly technology, which bring about excellent improvement of reliability of system. The 5kW class PEMFC system was operated under dynamic conditions for 1,000 hours and it showed a good performance of total efficiency and durability.

• 가정과삶의질연구
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• 제28권3호
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• pp.179-187
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• 2010

Since the late 20th century, construction companies have developed different brands of apartments while keeping the LOHAS, well-being, ubiquitous, and one-stop-living concepts in mind. From this point of view, this study intends to define the diverse space planning needs of apartment residents. The purpose of this study is to suggest optimum guidelines regarding the subject of space requirements and planning by conducting in-depth interviews of residents whose apartment floor size is between $66m^2$ (20 Pyong) and $165m^2$ (50 Pyong) and whose apartment is less than 5 years old. The major findings were as follows: (1) The shortage of storage space in different types of apartment housing units was found to be a chronic problem. Thus, closet sizes mustbe increased. (2) The size of the master bedroom needs to be decreased, whereas the size of the kitchen and dining room as well as the size of the second and/or third bedroom must be increased. More space is required in common areas occupied by the family and larger closets are needed. Less space is required for the master bedroom.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.904-907
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• 2003

We synthesized dendrimers containing light switchable units, azobenzene group. To apply to the molecular level devices or data storage system using Langmuir-Blodgett(LB) film, we firstly investigated the monolayer behavior using the surface pressure-area(${\pi}-A$) isotherms at air-water interface. And then the surface pressure shift of monolayer by light irradiation was also measured to the dendrimer with azobezene group. As a result, the monolayer of dendrimer with azobenzene group showed the reversible photo-switching behavior by the isomerization of azobenzene group in their periphery. This results suggest that the dendrimers with azobenzene group can be applied to high efficient nano-device of molecular level. And we measured the electrical properties by MIM and STM. The dendrimer with azobenzene group compared trans form and cis form at electrical properties.

• 한국기계가공학회지
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• 제6권3호
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• pp.85-91
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• 2007

This study was carried out to minimize the lifting force of a two hinge type stand mechanism. This unit is designed for the display devices in order to enhance the ergonomics for effective height adjustment and maintenance at any preferred position. The unit will be very useful for the mechanism fabricated with a coil spring and disc springs as a torque generator. The maximum and the minimum torque value should be calculated initially for the smooth lift. And the reasonable torque distribution is necessary to prevent any auto lift and auto dropping at any position because the torque generated by coil spring is more sensitive than disc spring in tilting the position. Therefore, the analysis of the coil spring is requisite to issue the specific torque value depending on the distorted angle with securing reliability of a long time storage condition. After the theoretical torque value was calculated, the evaluation was carried out by making a proto-type sample, then distorted angle was updated by experiment. The result of this study can readily be applied to various units for the optimization of the smooth lift.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1454-1457
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• 2003

This study was carried out to minimize the lifting force of a two hinge type stand mechanism. This unit is designed for the display devices in order to enhance the ergonomics for effective height adjustment and maintenance at any preferred position. The unit will be very useful for the mechanism fabricated with a coil spring and disc springs as a torque generator. The maximum and the minimum torque value should be calculated initially for the smooth lift. And the reasonable torque distribution is necessary to prevent any AUTO LIFT and AUTO Drooping at any position because the torque generated by coil spring is more sensitive than disc spring in tilting the position. Therefore, the analysis of the coil spring is requisite to issue the specific torque value depending on the distorted angle with securing reliability of a long time storage condition. After the theoretical torque value was calculated, the evaluation was carried out by making a proto-type sample, then distorted angle was updated by experiment. The result of this study can readily be applied to various units for the optimization of the smooth lift.

• The Plant Pathology Journal
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• 제34권3호
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• pp.241-249
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• 2018

Commercial biocontrol of microbial plant diseases and plant pests, such as nematodes, requires field-effective formulations. The isolate Pseudomonas chlororaphis O6 is a Gram-negative bacterium that controls microbial plant pathogens both directly and indirectly. This bacterium also has nematocidal activity. In this study, we report on the efficacy of a wettable powder-type formulation of P. chlororaphis O6. Culturable bacteria in the formulated product were retained at above $1{\times}10^8$ colony forming units/g after storage of the powder at $25^{\circ}C$ for six months. Foliar application of the diluted formulated product controlled leaf blight and gray mold in tomato. The product also displayed preventative and curative controls for root-knot nematode (Meloidogyne spp.) in tomato. Under laboratory conditions and for commercially grown melon, the control was at levels comparable to that of a standard commercial chemical nematicide. The results indicated that the wettable powder formulation product of P. chlororaphis O6 can be used for control of plant microbial pathogens and root-knot nematodes.

• 한국식품조리과학회지
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• 제22권3호통권93호
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• pp.386-395
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• 2006

The purpose of this study was to examine the perceptions and attitudes held by dietitians on seasoned processed meats. The questionnaires were distributed to x (Ed- give the sample size) dietitians at business foodservice operations in Kyungnam province. According to survey, 37.5% of the dietitians answered that it is 'very necessary' to develop seasoned processed meat products. Regarding desired product characteristics, the dietitians were asked about reduced additive use, good hygienic quality, nutritious and healthy quality, low salt content and adequate supply of nutritional information. Over half of the dietitians (59.2%) preferred Korean style seasoned processed meats. The cooking types of Korean seasoned processed meats chosen as new developments were steamed (21.3%), roasted (20.6%) and pilled (18.1%), while the expected frequencies of product usage were in the order of grilled (18.8%), roasted (15.6%), and fried (14.4%). The dietitians wanted no or only little increase in the price compared to current commercial products, units packed in 1 or 3kg sizes and a shelf life under refrigerated or frozen storage of 3-7 days. A minority of the dietitians (40.6%) responded positively to buy the seasoned processed meats if the products meet their needs.

• 대한산업공학회지
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• 제37권4호
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• pp.289-296
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• 2011

In most distribution centers, products are received from the suppliers in units of pallet, stored in a rack, moved to the picking area for replenishment, picked according to customer orders, and shipped to customers. In some distribution centers, however, replenishment is made in not a whole pallet but only a portion of a pallet load, mainly due to the limited space in the order-picking area; as a result, partially loaded pallets occupy cells in the rack. As the number of slow-moving items increases, more cells are occupied by partially loaded pallets so that fewer empty cells are available for storing full, incoming pallets. This will necessitate the construction or leasing of additional storage space, which will entail significant cost. As an alternative, we propose pallet consolidation, which involves moving a partial load to another partially-loaded pallet in order to create one empty cell in the rack. In this paper, we define three pallet consolidation problems; formulate each problem as a binary integer programming model; and present heuristic algorithms for the problems. The average performance of each of the proposed heuristics is evaluated using simulation.

• 한국산림과학회지
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• 제88권2호
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• pp.273-281
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• 1999

이 연구에서는 춘천국유림관리소 관할인 가리산 일대의 산림을 대상으로 다목적 산림경영을 추구하기 위하여 최적수확계획의 수립에 선형계획법을 적용하였다. 지리적 특성에 따라 연구대상지역을 4개의 경영단위 또는 유역으로 구분하였으며, 비감소수확, 현존 임분의 갱신시기, % 수확면적, 토사유출량, 목재생산량, 탄소저장량을 조절하기 위한 제약조건을 포함하였으며, 계획기간말의 임상구조 및 임분 갱신을 위한 수종선택 조건을 경영단위별로 적용하였다. 선형계획문제의 수식화에는 모델 I과 모델 II를 적용하였으며, 수식모형과 경영대안에 따라 최적해들을 비교검토하였다.

• 한국소음진동공학회논문집
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• 제26권3호
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• pp.298-307
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• 2016

In the building process of FPSOs(floating production, storage and offloading units) is the increasing demand of high performance piping joints that can be installed on its turret system and maintain smooth and long-term flow of ultra-high pressure crude oil, being subjected to external excitations such as wind and wave on the sea. Following such a trend, in this paper, a new-type piping joint of four effective degrees of freedom has been designed, and its dynamic characteristics predicted through mathematical modeling and computer simulations. Moreover, via an example it was shown how the yaw motion in particular can be independently controlled for future durability test despite strong kinetic couplings.