• 품질경영학회지
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• 제10권2호
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• pp.18-24
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• 1982

This paper estimates the reliability & mean time to failure (MTIF) of a cyclic or acyclic network system by the Monte-Carlo simulation method. Estimates of MTTF and Reliability become difficult as the complexity of a system increases. The method in this paper finds all simple paths from the given network, and then simulates the reliability of the required time and MTFF by using these paths. Life-times of the components in a network follow some probability distributions (Exponential, Weibull, Normal, Lognormal, etc.). The method, written in Level II. Basic Language, is validated for some simple examples and then estimates the reliability and MTFF of some cyclic network system.

• 한국산림과학회지
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• 제86권1호
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• pp.25-34
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• 1997

지구상의 잠재삼림면적을 추정하기 위한 일련의 단계로서, 적정한 식생도제작(Global Natural Vegetation Mapping, GNVM) 시스템을 선발하기 위해, Light Climatic Dataset(LCD)에 지형을 고려하지 않은 단순 시스템, LCD에 지형을 고려한 시스템, Heavy Climatic Dataset(HCD)에 지형을 고려한 시스템을 구축하고 상호 비교하였다. 3종류의 GNVM시스템은, 세계에서 관찰된 기후데이타를 구면보간법에 의해 지구면 전체의 $1^{\circ}{\times}1^{\circ}$의 격자점에 대하여 이것을 추정하고, 그 추정치로부터 식생을 구분하며, 구분의 결과를 가지고 잠재자연식생도의 출력 및 잠재자연식생의 면적을 산출한다. 3종류의 GNVM시스템을 비교한 결과, LCD에 지형을 고려한 GNVM 시스템이 잠재자연식생의 분포를 가장 잘 표현하였으며, 단순 시스템은 지형을 고려한 시스템들에 비해 온난한 지역을 과대평가하고 한랭지 및 사막지역을 과소평가하는 경향을 나타냈다. 한편, 측후소의 수에 따른 시스템간에 있어서는 HCD에 지형을 고려한 시스템이 측후소의 과밀분포로 인해 LCD에 지형을 고려한 시스템보다 습윤지역의 과대평가와 건조지역의 과소평가를 나타냈다.

• BMB Reports
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• 제40권3호
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• pp.444-447
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• 2007

Polymerase chain reaction (PCR) is a powerful technique in molecular biology and is widely used in various fields. By amplifying DNA fragments, PCR has facilitated gene cloning procedures, as well as molecular genotyping. However, the extraction of DNA from samples often acts as a limiting step of these reactions. In particular, the extraction of PCR-compatible genomic DNA from higher plants requires complicated processes and tedious work because plant cells have rigid cell walls and contain various endogenous PCR inhibitors, including polyphenolic compounds. We recently developed a novel solution, referred to as AnyDirect, which can amplify target DNA fragments directly from whole blood without the need for DNA extraction. Here, we developed a simple lysis system that could produce an appropriate template for direct PCR with AnyDirect PCR buffer, making possible the direct amplification of DNA fragments from plant leaves. Thus, our experimental procedure provides a simple, convenient, non-hazardous, inexpensive, and rapid process for the amplification of DNA from plant tissue.

• 한국산업정보학회논문지
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• 제6권4호
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• pp.12-21
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• 2001

최근 들어 작업강도가 심화, 노동환경의 변화 등으로 단순반복작업자의 누적외상장애가 많이 발생하고 있다. 따라서, 본 연구는 단순반복작업자의 근피로도를 분석하기 위하여 수작업과 Air Balance 시스템 설계장치를 이용할 때 각 근육의 피로도의 차이를 밝히고 단순반복작업의 기계에 의한 시스템설계제안을 목적하였다. 연구 결과, 내화벽돌 적재작업시에 수작업과 Air Balance 시스템을 이용한 근피로도 비교에서 Air Balance를 이용한 적재작업에서는 수작업 대비 근육별 AEMG 64.1%, MF 65.3%, MPF 64.3%, ZCR 63.6%로 근피로도가 낮게 나타났다. 근육의 동원정도는 전체적으로 비슷한 천이를 보였다. 즉, Aire Balance시스템을 사용하는 것이 수작업보다 근피로도 값은 낮게 나타났으며, 누적외상성 질환에 대한 노출도 작은 것으로 나타났다.

• 한국의류학회지
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• 제32권5호
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• pp.788-799
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• 2008

Since the late 20C, a lot of fashion designers have considered about new construction system in fashion. Many arguments about architectural form and construction system have being supported on enlargement of range of functionalism fashion through the consideration about new shape and combination among various any other spheres. Modular concept, which is able to divide complex construction of integration into separated basic unit and use various and liberal arrangements, is regarded alternative idea of economic construction that creates new shape and constructive beauty through the simple operation and changing combination continuously. Specially, fashion designs of Yoehlee Teng, John Ribber, and Galya Rosenfeld are estimated that they are effectively utilized architectural modular system pursuing multi-function and multi-change in fashion. Modular system utilized in fashion construction will be classified as follows: 1) layering system of Yoehlee Teng, 2) combine system of john Ribber, and 3) lego system of Galya Rosenfeld. This thesis will presents beneficial guide for simple and practical functionalism fashion design development in 21C.

• Structural Engineering and Mechanics
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• 제44권4호
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• pp.521-538
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• 2012

In this study, the transverse vibrations of an axially moving flexible beams resting on multiple supports are investigated. The time-dependent velocity is assumed to vary harmonically about a constant mean velocity. Simple-simple, fixed-fixed, simple-simple-simple and fixed-simple-fixed boundary conditions are considered. The equation of motion becomes independent from geometry and material properties and boundary conditions, since equation is expressed in terms of dimensionless quantities. Then the equation is obtained by assuming small flexural rigidity. For this case, the fourth order spatial derivative multiplies a small parameter; the mathematical model converts to a boundary layer type of problem. Perturbation techniques (The Method of Multiple Scales and The Method of Matched Asymptotic Expansions) are applied to the equation of motion to obtain approximate analytical solutions. Outer expansion solution is obtained by using MMS (The Method of Multiple Scales) and it is observed that this solution does not satisfy the boundary conditions for moment and incline. In order to eliminate this problem, inner solutions are obtained by employing a second expansion near the both ends of the flexible beam. Then the outer and the inner expansion solutions are combined to obtain composite solution which approximately satisfying all the boundary conditions. Effects of axial speed and flexural rigidity on first and second natural frequency of system are investigated. And obtained results are compared with older studies.

• 한국환경보건학회지
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• 제9권1호
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• pp.77-84
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• 1983

A study was carried out to find drinking water qualities of 56 simple piped water supply systems and 37 water pumps in Chun Sung Conutry, Kang Won Province from 1st July to 30th August 1981. 1. The results of all kinds of water test are found to be safe at only one out of fifty six samples of simple piped water supply system at two out of thirty-seven samples of water pump and unsafe at the others. 2. In general Count of Bacteria test, twelve (21.4%) out of fifty six samples of the simple piped water are found to be safe for the legitimate standard of safty water, and five (13.5%) out of thirty=seven samples of pump water. 3. Escherichia coli group is negative at seven (12.5%) out of fifty-six samples of simple piped water, and eight (21.6%) out of thirty-seven samples of pump water. 4. The results of the physical and chemical examination of drinking water specimen are found to be safe at twelve out of fifty-six samples of simple piped water and at twenty-eight out of thirty-seven samples of pump water.

• 대한기계학회논문집A
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• 제26권8호
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• pp.1552-1564
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• 2002

Meter-in, meter-out and bleed-off circuits are widely utilized in order to adjust the speed of a hydraulic actuator by using a flow control valve and in order to regulate the pressure of a hydraulic volume by using a simple on-off valve. In these circuits, a relief valve serves either to maintain constant system pressure or to protect the system from over-pressure loading. The relief valve of a bleed-off circuit is the second case frequently undergoing on-off action during operation. It makes the analysis of the pressure control characteristics of the circuit highly difficult. In this paper, steady-state flow rate, pressure, heat loss and efficiency of the three circuits are reexamined and basic experiments far obtaining the characteristics of a pump and relief valve are conducted. Finally, simple empirical first-order dynamic models of decreasing and increasing pressure were separately proposed and verified by comparison with experiment. As the result, the basis for the theoretical analysis of the pressure control characteristics of a bleed-off circuit using a simple on-off valve is established.

• 한국도서관정보학회지
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• 제44권3호
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• pp.489-512
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• 2013

본 연구는 뉴스 정보의 효율적인 색인 작성과 검색을 위한 뉴스 코어 시소러스를 구축하고 활용 방안을 제시한다. 뉴스 코어 시소러스는 뉴스의 모든 주제를 커버할 수 있는 매크로시소러스로 구축하여, 향후 정치, 경제사회, 문화 등의 마이크로시소러스를 부분집합으로 가질 수 있도록 하였다. 뉴스 코어 시소러스는 디스크립터 2,012어, 비디스크립터 74어를 SKOS(Simple Knowledge Organization System)로 구현하였다. 일간신문이 아닌 주간이나 격주간 등의 정보량이 적고, 특수한 주제를 다루는 신문은 특수 주제영역만 상세히 다루고, 대형의 뉴스 아카이브나 포털 사이트에서는 각각의 마이크로시소러스를 병합 또는 통합하여 활용할 수 있는 방안을 제시한다.

• 한국정밀공학회지
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• 제30권11호
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• pp.1161-1169
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• 2013

In this paper an omni-directional mobile robot is suggested for educational robot platform. Comparing to other robots, a mobile robot can be easily designed and manufactured due to its simple geometric structure. Moreover, since it is required to have low DOF motion on planar space, fabrication of control system is also simple. In this research, omni-directional wheels were adopted to remove the non-holonomic characteristic of conventional wheels and facilitate control system design. Firstly, geometric structure of a Mecanum wheel which is a most frequently used omni-directional wheel was demonstrated. Then, the organization of the mobile platform was suggested in aspects of mechanism manufacturing and electronic hardware design. Finally, a methodology of control system development was introduced for educational purpose. Due to an intuitive motion generating ability, simple hardware composition, and convenient control algorithm applicability, the omni-directional mobile robot suggested in this research is expected to be a promising educational platform.