• Journal of Biosystems Engineering
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• 제12권1호
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• pp.31-38
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• 1987

In order to improve the traditional post harvest system in Korea, a model for mechanized rice drying and storage system was developed and introduced as the first part of the study(Park, 1986). As the second part of the study, capital requirement and cost of the model system was analyzed. Also, optimum size of the model system was estimated by comparing with the traditional harvest system. From the study, the following results can be concluded: 1. The capital requirement of the model system decreases as the model size increases. For example, a model system having 500 ton storage capacity requires 439,000 Won/ton. However it requires 313,200 Won/ton only, if the model size increases to 1000 ton. 2. Also, total cost of the model system decreases as the model size increases. For example, total costs of the model system having 500 ton and 1000 ton storage capacity are 101,208 Won/ton and 69,320 Won/ton, respectively. 3. The breakeven point (optimum size) of the model can be estimated around 630 ton storage capacity if the operation rate is assumed as 100%. However, the optimum size of the model is 710 ton, if the operation rate it assumed 80%.

• 방송공학회논문지
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• 제8권4호
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• pp.365-380
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• 2003

MPEG-21 IPMP(Intellectual Property Management and Protection)가 DRM(Digital Rights Management)의 한 종류로서 1997년 표준화 활동이 추진된 이래로, 지금까지 몇 차례나 걸쳐서 표준작업 중단과 추진이 반복되었으며, 다시 2003년 이래로 새롭게 MPEG-21 IPMP 및 Reference Model에 대한 표준활동이 추진 중에 있다. 특히나 지난 2003년 10월 회의를 거쳐 수정된 CfP(Call for Requirement)이 보완 작성되었으며 아직 확정되지는 않았다 최종적인 CfP(Call for Proposal)는 12월 회의에서 발표되었고, 완성된 CfR은 2004년 3월 회의에서 최종 기술제안 요구사양서를 완성하여 6월까지 AHG 회의에서 최종적인 기술 제안을 받을 예정이다. 제안된 기술들은 7월 회의에서 W(Working Draft)로 완성될 예정이다 본 고에서는 이러한 표준 요구사항에 맞추어서 방송용 환경 아래 MPEG-21 IPMP과 Reference Model을 구성하고 실행하는 사례를 보여준다. 멀티미디어 스트림이 실시간으로 전달되는 방송환경에서 복합적으로 구성된 디지틀 아이템을 통하여 MPEG-21 각 요소별 기능들과 DIP(Digital Item Processing)에 실시간으로 사용자가 요구하는 동작을 보여준다. 이러한 방송용 적용 사례는 하나의 MPEG-21 part 기술을 적용하는 것이 아니라, 모든 part 기술들이 전체 MPEG-21 multimedia framework으로 구성되어 지적재산 보호 및 유통시스템이 매우 효율적으로 지원됨을 보여준다.

• 소성∙가공
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• 제33권4호
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• pp.277-284
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• 2024

Interest in remanufacturing of part has significantly increased to reduce used material and energy together. The directed energy deposition (DED) process has widely applied to remanufacturing of the part. An excessive residual stress takes place in the vicinity of the deposited region by the DED process due to rapid heating and rapid cooling (RHRC) phenomenon. The excessive residual stress decreases the reliability of the remanufactured part. Therefore, thermo-mechanical analysis for the remanufacturing of the part is needed to investigate heat transfer and residual stress characteristics in the vicinity of the deposited region. The thermo-mechanical analysis of a large volume deposition is significantly difficult to perform due to the requirement of a long computation time and a large computer memory. The goal of this paper is to investigate thermo-mechanical characteristics for remanufacturing of the ATC part using a DED process. The methodology of the thermo-mechanical analysis for a large volume deposition is proposed. From the results of analysis, heat transfer and residual stress characteristics during deposition and cooling stages are investigated. In addition, the proper deposition strategy from the viewpoint of the residual stress is discussed.

• 한국식생활문화학회지
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• 제20권1호
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• pp.21-34
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• 2005

The purpose of the study to examine the requirement of food service statistical account. the questionnaire was composed of two part: the traits of food service statistical accounts by USA and Japan and demographic characteristics. 325 questionnaires were distributed by mail to the member of Korean Food service Management Society and Korea university and college Culinary Management Faculty Association and 92 questionnaires were returned. the data was completed using the SPSS for frequency, mean, t-test, and ANOVA test. As a result of the follows. the 23 traits showed a high priority placed. Seeing the category, Number of customer, unit volume, solid waste, and information technology and application were higher than employee information. Comparing company members to academic members, both of them thought that dimension of unit, sales result, and number of customer. However, company member group indicated that employee information was important.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.622-626
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• 2001

Every design activity has a goal of satisfying a set of functional requirement. The commencement of a design, therefore, must have its foundation upon the identification of the functional requirements. Many of the design practices of the industrial examples can be categorized as design of small systems that are defined to have limited and fixed sets of functional requirements to be satisfied at all times. In the case of small systems it facilitates the construction of a knowledge-based system for a specific purpose to decompose the functional requirement and map ones in the lowest level into specific design features. When the number of design features is large, they need to be managed by groups. This paper suggests a grouping method for design process can be regarded as a series of selections of the predefined functional primitives according to the requirements and the preceding selections. An intelligent product design system for automatic transmission lever design is developed as an example.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.287-294
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• 1999

Vitamin and mineral deletion from swine diets can result in reduced growth if done during the period wher muscle and bone development is occurring. Several of the vitamins and minerals decline in the serum during the starter period, suggesting a higher dietary inclusion may be necessary postweaning. Vitamin research with grower-finisher pigs is limited, but results suggest that rapidly growing lean pigs may have a higher dietary requirement for the B vitamins. Several studies have suggested that early weaning and pigs of a lean genotype may have a dietary requirement for vitamin C, CI and Cr. High dietary vitamin E levels are fortified in the diet and seems to be effective in preventing mulberry heart problems in weanling and grower pigs. Organic Se is more effectively retained in muscle tissue than inorganic Se, approximately 20% less is excreted, but the bioavailability of organic Se for glutathione peroxidase activity is only 80 to 90% to that of sodium selenite. The active form of thyroxine (T4) is dependent upon a Se containing enzyme. Withdrawal of vitamins and minerals during the latter part of the finisher period has not affected pig performance responses, but studies with poultry suggest that the vitamin content of the meat may be reduced if the vitamins are withdrawn prior to marketing. High levels of vitamin E have been shown to improve pork quality, by reducing drip loss. Studies with vitamin C and Se have suggested that they may also be involved in pork quality.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권2호
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• pp.99-106
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• 2004

Train control system in LRT (Light Rail Transit) is developed as a part of "Light Rail Transit System Development Project". But there was no specific requirement representing the system safety. Because system safety must be ensured before the customization, we applied the system to a officially recognized specific procedure, such as "A Guideline to Ensure the Safety of Train Control System in Korea" that was officially announced by KNR (Korea National Railroad) in 2001. We should draw system safely requirement to guarantee system safety for the first time. In this paper, the hazard identification and analysis to derive the safety requirement on LRT train control system are carried out following the KNR guideline. To analyze hazard, we have to deduce system functions, identify related hazards, derive the effects of the hazards, analyze current risk, define the target risk of the system, and deduce the alternative plans to reduce the effects of the hazards. After the hazard analysis following the upper procedure, 30 hazards are identified and analysed. Especially detailed analysis on train collision that is a main hazard of the train control of system is specially carried out.

• 한국기계가공학회지
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• 제19권8호
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• pp.50-55
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• 2020

This study investigates the injection molding of a plastic rack gear and focuses on deflections in the part. The causes of deflections were found and resolved through a trade-off study by injection molding analysis. Based on a warpage analysis, the fiber orientation was found to be a dominant factor in the occurrence of deflections. Changes in the part design and various injection conditions were analyzed for their effects in reducing deflections. Based on the trade-off study, a new part bottom design, injection time, and melt temperature were recommended. A trial injection was done for the new plastic rack gear, and measurements showed that its flatness surpassed that of the original part and met the specified requirement. The short injection time, low melt temperature, and symmetric similar configuration of the part contributed to the reduction in deflections. Therefore, optimized gate design and injection conditions as well as a new part design were validated through injection molding analysis in this study.

• 정보처리학회논문지D
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• 제13D권7호
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• pp.909-922
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• 2006

프로덕트 라인 공학(Product Line Engineering)에서 핵심자산은 제품계열에 속하는 패밀리 멤버들이 어플리케이션을 만드는데 기초가 되는 모든 자산을 포함한다. 핵심자산 가운데 하나인 요구사항은 전통적인 시스템 개발에서와 마찬가지로 모든 핵심자산의 기초가 되는 부분이며, 다른 핵심자산의 공통성과 가변성(Commonality and Variability : C&V)을 결정하는 중요한 요소가 된다. 하지만 요구사항은 도메인 전문가 혹은 개발자가 경험에 기반하여 정형적인 프로세스 없이 분석하고 있으며, 동일한 도메인 요구사항임에도 불구하고 요구사항이 재사용 되지 않고 있다. 따라서 도메인 요구사항은 객관적인 방법을 통해 공통성과 가변성을 도출하고 이를 재사용 할 수 있는 프로세스가 정립되어야 할 필요가 있다. 이에 본 논문에서는 도메인 요구사항을 객관적인 근거에 따라 분석할 수 있는 4가지 활동 즉 도메인 범위 결정, 도메인 요구사항 추출 및 일반화, 도메인 요구사항 분석 및 모델링, 도메인 요구사항 변경 관리 활동 및 그에 따른 세부적인 활동을 제시하였다. 이를 요구사항 관리에 적용할 경우 분석한 도메인 요구사항과 관련된 아키텍처 혹은 컴포넌트의 재사용성 증대를 통하여 제품 개발기간과 비용을 줄이며 생산성을 향상시키는 등의 장점을 가져올 수 있을 것으로 기대한다. 또한 프로덕트 라인 공학에서 핵심자산의 기초가 되는 요구사항을 체계적으로 분석하고 관리함으로써, 요구사항을 기반으로 산출되는 다양한 산출물의 품질을 높일 수 있을 것으로 기대한다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.42-47
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• 2004

This paper describes basic structural design for the large floating crane barge of fixed undulation type. Structural analysis is performed to divide two parts because crane barge is composed two parts, crane part of jib boom back stay and back tower and barge part to support crane part. The structural strength for jib boom structure members are in compliance with JIS B 8821 and scantling of all barge structural members are in compliance with the requirement of KR (Korean Register of Shipping) Steel Barges and Rules for Classification of Steel Ships. For the structural analysis of large floating crane, MSC/NASTRAN & MSC/PATRAN software is used.