• 산업공학
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• 제11권2호
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• pp.199-209
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• 1998

In manufacturing industries, one of the critical issues is to synchronize the sequence of production operations with materials needed at each operation to improve productivity. In order to solve this synchronization problem. We develop a code system entitled 'Work-Order-Number' for automated storage/retrieval systems(AS/RS) in this paper. The Work-Order-Number is designed for the purpose of integrating the engineering information. material handling, production and operations scheduling, point of production, and AS/RS systems. This paper implemented the Work-Order-Number in the electric motor manufacturing. The results of the implementation showed the reduction of the number of workers in material handling and cost-loss due lo a late delivery.

• 설비공학논문집
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• 제21권9호
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• pp.496-504
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• 2009

In order to investigate the feasibility of a direct ice slurry transporting system for the purpose of district cooling, a case study of field application is performed. The research aims include the field measurement of ice packing factor, the performance of coldness delivery, and the branching characteristics of ice slurry. Two representative types of pipe branch are dealt with in this work. For the slurry flow with ice volume fraction of 0.16 or less, the pipe blocking due to aggregation is not observed. Based on the time-wise variation of temperature in the storage tank, a calculating method of ice packing factor is newly developed, which seems to be useful when the brine concentration is unknown. It is confirmed that the mass flow rate of ice slurry per unit cooling load is markedly reduced with increasing the ice content. The pumping power also decreases, but remains unchanged for high ice fractions. The distribution of ice particle before and after branching shows a good uniformity within the range of 5% difference, but yields a unique trend depending on the flow rate.

• 한국농공학회지
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• 제16권1호
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• pp.3263-3291
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• 1974

Experimental work of grain bin was carried out to develop the methods of natural air in-bin drying and storage. The method is considered to be more economical, labour saving, and an effective countermeasure to grain loss. To examine the possibility of farm use of the grain bin and to analyze the related factors concerned with in-bin grain drying and storage, ambient air conditions (especially the change of air temperature and relative humidity) and grain quality during drying and storage periods were investigated. A laboratory model bin was constructed to investigate the effect of different forced air conditions on the drying characteristics of rice. In addition, a grain bin with 2.2m diameter and 1.8m height, considered to be the optimum size for the average Korean farm, was constructed and tested to examine the drying and storing characteristics of rice. The weather data analyzed in this study was the nine-year (from 1964 to 1972) record of air temperature and relative humidity in the Suweon area, and the thirty-year (from 1931 to 1960) record of pentad normal relative humidity and air temperature in the Seoul area. From the results of the weather data analyses, the adequate air delivery hours (which was arbitrary defined as the condition to give less than 75% relative humidity) to dry the rice during October were about nine hours (from approximately 10 A.M. to 7 P.M, ) a day, in which the average air temperature was about 15.9$^{\circ}C$ and average relative humidity was 66%. The occurence of days having three hours of such conditions was 1, 2, and 1-day within the 1st, 2nd add last 10-day periods for the month of October, respectively. Therefore, it may be considered that the weather condition in October was satisfactory for the forced natural air drying. The results of the laboratory model bin test were analyzed to obtain the drying curve and drying rate for different drying stages and grain layers in the bin corresponding to various conditions of forced natural air. A drying experiment with a prototype grain bin showed that an approximate 5 percent grain moisture gradient through a 1.6 meter grain deposit was observed after 80 hours of intermittent drying, giving an over dried zone in the lower grain layers and an extremely high grain moisture zone in the upper layers. This indicates that an effective measure should be taken to reduce this high moisture gradient. In order to investigate the drying characteristics of bulk grain in a layerturning operation a grain bin test was performed. This showed a significant improvement of uniform drying. In this test, approximate 107 hours were required to dry a depth of 1.6 meter of grain from an initial moisture content of 22.2 percent to a moisture content of 16.7 percent using an air delivery rate of 2.8 cubic meter per a minute per every cubic meter of grain. This resulted in a 2 percent moisture gradient from the top to the bottom of the bin. During storage period, till the end of June the average temperature of grain was 2~3$^{\circ}C$ higher than ambient air temperature. But during July when the grain moisture content went up slightly (less than 1 percent), the average temperature of the grain also increased to 3~5$^{\circ}C$ higher than ambient air temperature. It is therefore recommended that for safe grain storage, grain should not be stored in sheet metal bins after mid May. From the above results, in-bin rice drying and storage can be used effectively on Korean farms. It is strongly recommended that the use of grain-bin system should be implemented for farm use to improve farm drying and storage of rice.

• 산업경영시스템학회지
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• 제22권52호
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• pp.155-170
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• 1999

I think that there are few domestic enterprises that recognize standardization of logistics equipments is necessary, which causes a lot of waste in costs and also reduces their business competitiveness. The purpose of this paper is to make the companies be aware of this situation, to exactly analyze where the Korean logistics equipments status are, and further to provide practical directions of methods and activities for effective standardization. Through analysis in the study, there were some findings, as listed below. First, the standardization level of each company varies depending on its own corporate characteristics. Second, if a company adopted standardization process in logistics equipments, it would accelerate process of work efficiency or productivity. Third, when logistics equipment are standardized, it would boost efficiency in storage utilization. Fourth, the delivery services through this standardized logistics would be implemented at a higher speed than before due to the accelerated flow of materials. According to the above findings, it is confirmed that logistics standardization would greatly affect on business performance positively. For the domestic manufactures to facilitate logistics system more easily, as an easiest way, it is required to build logistics standardization teams and surveys. Then afterwards, to achieve it earlier than expected, the company-wide education and training for workers have to be followed to let them be aware of necessity and inevitability about standardized logistics.

• 조명전기설비학회논문지
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• 제22권5호
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• pp.53-57
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• 2008

일반적으로 비상시 전원으로 디젤발전기를 가장 많이 사용하고 있으며, 하이브리드 전원소스(상용전원, 축전지, 연료전지, 태양전지 등)를 사용하여 부하에 안정적인 전력을 공급하기 위한 방법들이 연구되어지고 있다. 최근 비상시 전원으로 가장 많이 사용하고 있는 디젤발전기의 역할이 아주 중요하게 여겨지며, 운영부하에 따라서도 유연하게 동작되어야 하고, 신뢰성도 확보되어야 한다. 따라서 본 연구에서 부하 변동에 따른 최대전력 추종제어 기능이 가능하고, 고조파 억제 기능 및 안정주파수 유지기능이 가능하도록 부하 변동에 따른 디젤발전기의 제어기에 대하여 논하고자 한다.

• 한국항만학회지
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• 제6권1호
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• pp.93-110
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• 1992

The most change in this century is supposed to be declination of ideology, and block of world economy. Addition to down full of cold war atmosphere around Northeast Asia, not only economic and social mood in this region is dramatically changed, but also it gave birth to the block of Northeast economy that accerlated new hub of world economy. According to dramatic change of economic surroundings the dynamic potential of growth in this region will be guided to enlarge inter-regional trade and increase volume of trade, thus suggests to grow steadily transportation. cargos in this region will have to arrange the system of delivery and inner transportation, accessary facilities, inter-regional harbors if North America and EC has connected easily. As have accerlated GATT and UR represented multilateralism and regionalism, it has regulated to increase trades of region due to relief of the trade barrier through specific areas has agreed with separately. The flow of regionalism of world economy has appeared to realize EC and NAFTA centered U.S.A, and also has presented to free trade region or one-size market agreement in Asia as APEC, EAEG in Malaysia, and etc. In defense to this block and internationalism of world economy, Pusan has to come forward to the hub of Northeast others has proposed a project to dominate the Northeast, Economy Association Agreement as Far East comprehensive development project in USSR, Hunchun development project in NK, and East Sea development project in PRC, Niigate regional development in Japan, Duman River development project in NK, and East Sea development project in Korea. As this exercise has proceed, Pusan also have arranged development strategy definitely and prepared provisions systematically. Engaging to participate center of delivery system is meant to be completed complex functions, namely the transfer storage processing & assembly function of international commodity. Pusan has ability to be terminal point of TSR. it had been connected to EC as the biggest economy block and TKR as complex transportation root to Far East, it would be the center of inground and seabase delivery terminal to Rotterdom as the biggest container pier and major piers to North-East and South East Asia. In order to provide a Role of 21 century's internationalization, Pusan has appealed to participate in management information research and development connected to Pohang-Ulsan-Changwon-Masan, and has utilized efficiently the resources such as man, material, money and information.

• 한국정보통신학회논문지
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• 제24권7호
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• pp.879-884
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• 2020

기존의 비디오 파일 시스템에서는 비디오 파일들이 대용량의 하드디스크 혹은 디스크 어레이를 보유한 고성능 서버에 저장되어 있다. 3D 인터넷 방송을 위해서는 비디오 파일을 다수의 클라이언트들에게 전송하는 과정에서 실시간 처리가 요구된다. 본 논문에서는 5G 환경에서 많은 사용자에게 실시간으로 서비스를 제공할 수 있는 3D 인터넷 방송 시스템의 설계를 보여준다. IP 멀티캐스트 기술은 라우터 환경의 제약으로 인하여 실제 대부분의 인터넷을 통한 동영상 콘텐츠 전송은 유니캐스트 기반의 서비스가 대부분이다. 또한 VOD와 같은 On-Demand 환경의 멀티미디어 방송 서비스 등은 서비스 제공자에게 막대한 시스템과 네트워크 자원을 요구하므로 3D 인터넷 방송 환경에 적용하기 어렵다. 사용자 시스템 자원을 통한 전송 방법으로서 활발히 연구가 진행되고 있는 오버레이 멀티캐스트 기법은 라이브 방송, 화상회의 등의 다수의 사용자 그룹 전송에 적합한 응용을 위해 최적화 되어 있어 IP 멀티캐스트 대안으로서 각광 받고 있다. 본 연구에서는 호스트 기반 멀티캐스트에서 발생하는 성능 저하 요인들을 최소화하여 효율적인 데이터 전송을 제공하는 3D 인터넷 방송 시스템을 구성한다.

• Journal of Dairy Science and Biotechnology
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• 제39권1호
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• pp.27-35
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• 2021

본 연구에서는 CPP와 CSO를 사용하여 제조한 나노 복합체의 유식품 적용성 및 포집된 생리활성물질인 비타민 D의 in vitro release를 평가하였다. 그 결과, CPP/CSO 나노 복합체는 model milk 및 model yogurt 적용 후 12일간의 저장기간 동안 높은 물리적 안정성을 지녀 식품 적용성이 뛰어남을 규명하였다. 또한 제조 공정 요인인 CPP 농도와 pH 조절을 통해 비타민 D를 90% 이상 포집할 수 있었으며, in vitro release 평가를 통해 비타민 D를 위에서 보호하고, 장에서 release 하는 나노 복합체의 특성을 규명하였다. 결론적으로 본 연구에서 제조된 CPP/CSO 나노 복합체는 뛰어난 유식품 적용성을 지닐 뿐만 아니라, 칼슘흡수 증진을 위한 비타민 D를 효과적으로 포집할 수 있으며, 포집된 비타민 D를 소장까지 안전하게 전달할 수 있는 효과적인 나노 전달체로 활용될 수 있을 것으로 기대된다.

• 한국농촌간호학회지
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• 제3권2호
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• pp.96-103
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• 2008

Purpose: The Study of vaccination for infants and children business in Primary Health Care Posts from 1980 to 2009. Method: look for national essential vaccination look for the change of vaccination by the times in Primary Health Care Posts and the rate of vaccination for infants and children by a administrative report statistics survey of a vaccine delivery system of Public health care institutions investigation about assistance details of vaccination cost in order to raise the rate of vaccination for infants and children. Results: In 1980s, there are many infants and children management object, but now there are rapidly decreasing infants and children management subject of a Primary Health Care Post because of rural exodus phenomenon of 1990's and a low birthrate of 2000's. Currently, the infants and children that registed, and managed to a Primary Health Care Post is most multi-cultural families. A multi-cultural family assistance program is provided these infants and children to the objects. Conclusions: Infant vaccination execution in Primary Health Care Posts showed to high vaccination rate because the prevention of vaccination delay or omission of the interior child who raised geographical accessibility to object sons nowadays it difficult to management of transportation of vaccine and storage management for a little shroud objects limited and management of inoculation business in quality. A main problem is as follows. There are a little vaccine transportation, trouble of proper temperature maintenance of a storage process, and having a lot of vaccine abolition as a little objects, educational training shortage of health care practitioner regarding to execute an inoculation. Therefore, vaccination business needs measures for management in quality in Primary Health Care Posts.

• 한국수소및신에너지학회논문집
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• 제26권2호
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• pp.114-119
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• 2015

Nowdays, fossil fuels have been used as an important resource in development of industry. But it is limited and caused climate change such as pollution and global warming. So nuclear fusion research is being issued with tritium to develop eco-friendly and sustainable energy. Republic of Korea is in charge of Storage and Delivery System (SDS) in the International Thermonuclear Experimental Reactor (ITER), weld present in the SDS bottles are easily exposed to the hydrogen embrittlement of special characteristics of the hydrogen in hydrogen atmosphere, When the hydrogen embrittlement is rapidly progresses, the cracking is generated in the weld zone. Due to this cracking, the risk of leakage of tritium into the atmosphere occurs. In this study, hydrogen heat treatment was processed through the Pressure-Composition-Temperature (PCT) device according to the time variation. Also mechanical properties such as rupture strength test, three point bend test and hardness test in accordance with the respective time have been conducted and the fracture was observed by scanning electron microscopy(SEM) after the mechanical properties evaluation.