• 제목/요약/키워드: Carry-out

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다중프로세서 시스템 환경에서 병렬 루프 스케쥴링 알고리즘 (A Parallel Loop Scheduling Algorithm on Multiprocessor System Environments)

  • 이영규;박두순
    • 한국멀티미디어학회논문지
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    • 제3권3호
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    • pp.309-319
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    • 2000
  • 병렬 스케줄링의 목적은 다중프로세서 시스템 환경에서 병렬성을 가진 응용프로그램에 대해 최소의 동기화 오버헤드와 부하균등(load balance)을 달성하도록 스케줄링을 수행하는데 있다. 프로세서들이 병렬 반복(iteration)을 실행하기 위해서는 메모리로부터 반복들에 대한 chunk를 계산하고 할당받게 된다. 이때, 전역 메모리의 상호 배타적인 빈번한 접근으로 많은 스케쥴링 오버헤드 및 병목현상이 발생된다. 또한, 프로세서에게 할당된 chunk내 병렬 반복들의 분포가 서로 상이한 경우,각 chunk의 실행시간이 서로 달라 부하불균등의 원인이 되어 결과적으로 전체 스케쥴링 성능에 나쁜 영향을 준다. 따라서, 최소의 스케줄링 오버 헤드와 부하균등을 달성하기 위해 본 논문에 서는 기존의 방법들에서 문제점들을 도출하고, 자료의 국부성과 프로세서 동족성(affinity)을 고려한 병렬 루프 스케줄링 알고리즘을 제안한다.

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불규칙성 박판제품의 프로그래시브 다이설계를 위한 자동화된 CAD시스템 (An automated process planning 8 die design using expert system for blanking or piercing of irregular shaped sheet metal products)

  • 김재훈;김철;최재찬;김병민
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.214-218
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    • 1995
  • Much labor, an exceedingly long lead time, and the skills of experienced engineers are required for press tool design. To reduce such problems, several CAD systems for blanking or piercing have been developed. This paper describes a computer-aided design for blanking or piercing of irregularly shaped sheet metal products. An approach to the system is based on knowledge base rules. The process planning & die design system is designed by considering several factors, such as complexity of blank geometry, punch profile, and availability of press equipment and standard parts. Therefore, after checking a production feasibility for irregular shaped sheet metal products, this system which is implemented strip layout module can carry out a process planning and generate the strip layout in graphic forms. Also this system implemented die layout module can carry out a die design for each process which is obtained form the result of an automated process planning and generate parts and assembly drawing of a die set.

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차체구조의 구조기인 내구 설계 (Structure Borne Durability Design of a Vehicle Body Structure)

  • 김효식;임홍재
    • 한국자동차공학회논문집
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    • 제12권3호
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    • pp.109-121
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    • 2004
  • This paper presents an optimal design method for structure-borne durability of a vehicle body structure. Structure-borne durability design requires a new design that can increase fatigue lives of critical areas in a structure and must prohibit transition phenomenon of critical areas that results from modification of the structure at the same time. Therefore, the optimization problem fur structure-borne durability design are consists of an objective function and design constraints of 2 types; type 1-constraint that increases fatigue lives of the critical areas to the required design limits and type 2-constraint that prohibits transition phenomenon of critical areas. The durability design problem is generally dynamic because a designer must consider the dynamic behavior such as fatigue analyses according to the structure modification during the optimal design process. This design scheme, however, requires such high computational cost that the design method cannot be applicable. For the purpose of efficiency of the durability design, we presents a method which carry out the equivalent static design problem instead of the dynamic one. In the proposed method, dynamic design constraints for fatigue life, are replaced to the equivalent static design constraints for stress/strain coefficients. The equivalent static design constraints are computed from static or eigen-value analyses. We carry out an optimal design for structure-borne durability of the newly developed bus and verify the effectiveness of the proposed method by examination of the result.

안경업 진입규제 완화의 문제점들 (The Problems of Relaxed Entry Regulation for an Optical Shop)

  • 김상현;김대현
    • 한국안광학회지
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    • 제15권1호
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    • pp.31-38
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    • 2010
  • 목적: 본 논문에서는 안경원의 진입 규제 완화에 대한 공정거래위원회 보고서의 문제점과 개선방안들을 다루었다. 방법: 안경업 진입규제완화를 주장하는 공정거래위원회 보고서 각각의 내용을 분석하였다. 결과: 안경사와 안경원의 공급은 현재도 과포화 상태이며, 외국사례의 경우는 우리의 현실과 맞지 않는다. 정책을 실행하기 위해서는 무엇보다도 제도 개선이 선행되어야 한다. 그리고 안경사들과 정부를 다 만족시키기 위해서는 신중을 요하는 균형이 잡힌 조치가 필요하다. 결론: 현 시점에서 규제완화정책을 실행하기에는 시기상조이며, 장기적인 관점에서 보아야 한다.

바인더 첨가에 따른 $Al_{18}B_4O_{33}/AC4CH$의 파괴인성에 관한 연구 (A Study on Fracture Toughness Properties of $Al_{18}B_4O_{33}/AC4CH$ by Binder Additives)

  • 신동인;정재욱;박원조;허선철;김형진
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.61-66
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    • 2003
  • In this paper, the effect of binder additive on the fracture toughness was metal matrix composite produced by squeeze casting method. In this study using the matrix is AC4CH and reinforcement used Aluminum borate whisker. Each MMC was produced by add inanimate binder ($SiO_2,\;Al2O_3,\;TiO_2$) to whiskers for increase the binding together of whiskers. Fracture toughness test were carry out in accordance with the ASTM E-399 standard test method, W=25mm, b=12.5mm CT(half size) specimen. However Base metal AC4CH was not meet the qualification of $P_m/P_Q<1.1$, so that test were performed $J_{IC}$ test. $K_{J_{IC}}$ value was measuring by $J_{IC}$ value change into $K_{IC}$. $J_{IC}$ test was carry out in accordance with the ASTM 1820.

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Green and Healthy Living in a High-rise, High Density Urban Environment: The Hong Kong Housing Authority's Experience

  • Fung, Ada Y.S.
    • 토지주택연구
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    • 제5권3호
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    • pp.131-136
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    • 2014
  • The Hong Kong Housing Authority (HKHA) develops and implements a public housing programme to meet the housing needs of people who cannot afford private rental housing. The HKHA has an existing stock of about 740,000 public rental flats (PRH). According to the 2014 Policy Address, the Government aims to provide an average of about 20,000 PRH units and about 8,000 Home Ownership Scheme (HOS) units per year. We care for the environment. In developing new housing estates, we conduct thorough environmental studies such as microclimate studies and air ventilation assessment, and use passive design to harness the natural characteristics of our sites. We employ environment-friendly design and construction methods, using modular flat design, pre-cast and pre-fabricated construction techniques as well as recycled, green construction materials. We conduct Carbon Emission Estimation for all our projects, conserve the use of natural resources and reduce wastes throughout the life cycle of buildings. We care for people. We adopt the principles of Universal Design and Barrier Free Access for the convenience and welfare of people of all ages and abilities. We carry out Community Engagement to collect stakeholders' views and aspirations, and incorporate them in the design of our projects. We also carry out surveys of residents' views after the occupation of new estates to gauge our success and identify areas for improvement.

소규모 시스템의 요건에 의한 설계 (A Requirements Driven System Design Process for a Small System)

  • 김의중;신근하;최재성
    • 한국정밀공학회지
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    • 제18권10호
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    • pp.69-75
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    • 2001
  • Systems engineering has been utilized in system development primarily for large-scale projects or commercial large-scale systems during the last several decades. We can understand why it would be useful to apply systems engineering to the development of a relatively small system. However, it is difficult to effectively carry out a project due to the complexity in applying the methods of systems engineering. To apply systems engineering to the development of a small system, the system engineering processes should be tailored. We established a requirements driven system design process(RDSDP) that can effectively carry out the system design far a small system. RDSDP is a system design process that treats all the requirements thoroughly and effectively. This is applied by the designer according to a standardized and systematized process during the first phase in design, in which system specifications are made. By using RDSDP, we can affect a reduction of the number of redesign phases in the process of the system design, shorten the period for to make specification, which will then cause the system to succeed in the actual application.

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치과병원 치과위생사의 환자안전문화에 대한 인식 분석 (An Analysis on the Dental Hygienists' Perception of Patient Safety Culture at Dental Clinics)

  • 정지은;황다혜;윤현경
    • 보건의료산업학회지
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    • 제7권4호
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    • pp.81-92
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    • 2013
  • This research was conducted to analyze the perception of the dental hygienists who work in ordinary dental clinics regading patient safety culture and to analyze the related elements. As for the research subjects and methods, 233 dental hygienists who work at the dental clinics located in Daegu, Gyeongbuk and Jeonnam were targeted from February 6, 2012 to March 5, 2012 to administer survey by utilizing patient safety culture recognition tool. Collected data was subjected to the SPSS 18.0 program to calculate average and standard deviation, and to carry out t-test, ANOVA and multiple regression analysis. Dental hygienists' level of perception towards patient safety culture was mid level, and it was demonstrated that there is a correlation with age, work experience at department, title and type of department that affect level of perception towards patient safety culture. In conclusion, Since this research targeted only a limited number of dental hygienists, it is necessary to be cautious about over-interpreting the results. Above anything, it is necessary to carry out repetitive research by targeting medical professionals of diverse jobs.

Region Classification and Image Based on Region-Based Prediction (RBP) Model

  • Cassio-M.Yorozuya;Yu-Liu;Masayuki-Nakajima
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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    • pp.165-170
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    • 1998
  • This paper presents a new prediction method RBP region-based prediction model where the context used for prediction contains regions instead of individual pixels. There is a meaningful property that RBP can partition a cartoon image into two distinctive types of regions, one containing full-color backgrounds and the other containing boundaries, edges and home-chromatic areas. With the development of computer techniques, synthetic images created with CG (computer graphics) becomes attactive. Like the demand on data compression, it is imperative to efficiently compress synthetic images such as cartoon animation generated with CG for storage of finite capacity and transmission of narrow bandwidth. This paper a lossy compression method to full-color regions and a lossless compression method to homo-chromatic and boundaries regions. Two criteria for partitioning are described, constant criterion and variable criterion. The latter criterion, in form of a linear function, gives the different threshold for classification in terms of contents of the image of interest. We carry out experiments by applying our method to a sequence of cartoon animation. We carry out experiments by applying our method to a sequence of cartoon animation. Compared with the available image compression standard MPEG-1, our method gives the superior results in both compression ratio and complexity.

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A Study on Transmission System Expansion Planning using Fuzzy Branch and Bound Method

  • Park, Jaeseok;Sungrok Kang;Kim, Hongsik;Seungpil Moon;Lee, Soonyoung;Roy Billinton
    • KIEE International Transactions on Power Engineering
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    • 제2A권3호
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    • pp.121-128
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    • 2002
  • This study proposes a new method for transmission system expansion planning using fuzzy integer programming. It presents stepwise cost characteristics analysis which is a practical condition of an actual system. A branch and bound method which includes the network flow method and the maximum flow - minimum cut set theorem has been used in order to carry out the stepwise cost characteristics analysis. Uncertainties of the permissibility of the construction cost and the lenient reserve rate and load forecasting of expansion planning have been included and also processed using the fuzzy set theory in this study. In order to carry out the latter analysis, the solving procedure is illustrated in detail by the branch and bound method which includes the network flow method and maximum flow-minimum cut set theorem. Finally, case studies on the 21- bus test system show that the algorithm proposed is efficiently applicable to the practical expansion planning of transmission systems in the future.