• 제목/요약/키워드: Take a Reasonable

검색결과 272건 처리시간 0.027초

토목섬유 interface의 변형율 연화 모델 개발 (Development of Strain-softening Modeling for Interfaces between Geosynthetics)

  • 서민우;박준범;박인준;조남준
    • 한국지반신소재학회논문집
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    • 제2권1호
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    • pp.57-68
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    • 2003
  • Strain-softening model is developed to characterize the interface behavior of geomembrane with geotextile and geosynthetic clay liner(GCL). The model proposed in this research is calibrated by using data from direct shear tests conducted on smooth and textured geomembrane. The research is divided into two regions, pre-peak and post-peak, to take into account of strain-softening effect. Although slight difference between measured and back calculated data is observed under high normal stress, good agreements, in general, are found from back calculations. Especially, good consistency is observed in the case of low normal stress. Based on the results, it can be concluded that the proposed model can be a reasonable constitutive law to figure out the behavior of strain-softening between interfaces of geomembrane. In addition, DSC(Disturbed State Concept) model is also presented for further application in geosynthetic interfaces.

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수직 이착륙기의 고온 고속 배기열에 의한 함정 갑판의 열유속 계산을 위한 수치모델 (Numerical Estimation of Heat flux on the Deck Exposed to the High Temperature Impinging Jet of VTOL Vehicle)

  • 장호상;황세윤;최원준;이장현
    • 한국군사과학기술학회지
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    • 제21권1호
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    • pp.74-85
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    • 2018
  • This study has analyzed the convective heat transfer on the deck exposed to the high-temperature impingement exhausting from a VTOL vehicle. The heat flow of the impingement on the deck is modeled by the convection heat transfer. The convective heat flux generated by the hot impinging jet is investigated by using both convective heat transfer formulation and conjugate heat transfer formulation. Computational fluid dynamics(CFD) code was used to compute the heat flux distribution. The RANS equation and the k-e turbulence model were used to analyze the thermal flow of the impinging jet. The heat flux distribution near the stagnation zone obtained by the conjugate heat transfer analysis shows more reasonable than the convective heat transfer analysis.

베이스플레이트식 체결장치의 앵커볼트 설계 (Design of anchor-bolt for the rail fastening system with baseplate)

  • 김은;장승엽;조용진
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.508-513
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    • 2006
  • Anchor bolt in baseplate fastenings on the slab track is an important component to conform placing and safety of fastenings. Due to the way of load transmission control of fastenings, sometimes anchor bolt has to be applied lateral load. So we have to take care for it when we design. Especially, in the case of anchor bolt which is applied loads repeatedly, we have to consider fatigue failure. If parts of machine are damaged in static loads, stress will exceed the yield strength. So parts could be transformed largely. Therefore because they are visible to the naked eyes, we can replace parts before failure. However, because fatigue failure that are invisible to the naked eyes happen unexpectedly, it's very dangerous. To make a reasonable design of anchor bolts, we will analyze them by changing diameters of anchor bolt, quality of insert, initial gap between anchor bolt and insert, the presence of insert, etc. which affect the stresses of anchor bolts. We can get the maximum and minimum amplitude of stress through the modified Goodman diagram or Smith diagram which represents limit of all strengths and stress components to the average stress. We also tried to show the way of examining the expected th life of anchor bolt briefly through considering above.

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수산·해운계 고등학교 교과의 해양환경 내용분석 (The Contents Analysis of Ocean Environment of Textbooks for Fisheries and Marine High School students)

  • 김삼곤;김종화
    • 수산해양교육연구
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    • 제16권2호
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    • pp.143-155
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    • 2004
  • The aims of this study are to analysis about the contents associated with the ocean environment compared 17 special-subject textbooks to 2 common-subject textbooks, and to make some proposals for construction of contents. The results of it are as follows; 1. Only 17 books among 36 textbooks taught by the fisheries and marine high schools are contained to some contents related with ocean environment. The contents associated with the ocean environment take possession of 90%, 62% each of total pages in the textbooks, 'ocean pollution' and 'ocean environment'. 2. Of compulsory texts, namely, 'general fisheries', 'general ocean' and 'information treatment of fisheries-marine', the former 2 books are composed of 4.5%, 36.2% each relating with ocean environment. But the last one is nothing. 3. Therefore, even a little contents of ocean environment and its conservation, it is necessary to add as the reasonable rate to the characteristics of each book in 36 special-subject textbooks. 4. And also it is shown that the common-subject textbooks,'ocean science', ' earth science I' and 'earth science II', are composed of 35.7%, 10%, 16.7% each. So we'd like to recommend that the contents of ocean pollution and environmental conservation have to add more.

품(品)과 질(質)의 연원(淵源)을 통해 살펴본 현대품질경영의 의미 (A Study on the Meaning of Modern Quality Management from the Etymological Perspective of the word PumJil (品質))

  • 서진영;성시훈;유한주;송오현
    • 품질경영학회지
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    • 제44권1호
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    • pp.61-76
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    • 2016
  • Purpose: In order to use a word as academic terminology, we must first take a look at the meaning of that word as it is commonly used and then consider whether or not the connotation of that word is suitable to be used as academic terminology. Presently, the word Pumjil(品質) is being used as academic terminology occupying an important position in the field of business administration in Korea and is usually translated into English as 'quality'. The same is true in Japan. However, as is the case with many Korean words, the meaning that the word implies has a tendency to change gradually over time. This tendency can account for the changes or additions to the meaning a word connotes. Methods: This dissertation aims to escape from such biased ideas and study the meaning of 'Pum-Jil品質' from the view of humanities and exegetics. Then the natural definition of the word as far as business administration is concerned can be considered. Results: 'Pum-Jil品質' has been used amid changes in modern times(historic texts in both Korea and China. In Korea particularly, the word was used in the royal court until comparatively modern times.), and now it is also widely used in the field of business administration. In this process of change, a notable point is that 'Pum-Jil品質', which was originally used to mean 'nature or character of a man', took on a new meaning, 'a certain quality of a thing or a good'. Conclusion: 'Pum-Jil品質' should require basic functional 'quality' of goods or services as a prerequisite. And the functional quality should meet consumers' needs, as the pledge (trust; 信賴) for quality is between suppliers and consumers. Without consumer's trust for goods, the relationship between suppliers and consumers cannot be maintained. So goods must exchange with trust, not expenses. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics.

모듈러 지중아치 구조 안전성 검토를 위한 간략 해석 및 평가방법에 관한 연구 (A Study on Simplified Analysis and Estimation Method for Evaluation of Structural Safety in Modular Underground Arch Structure)

  • 권태윤;조광일;이원홍;안진희
    • 한국구조물진단유지관리공학회 논문집
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    • 제26권3호
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    • pp.55-63
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    • 2022
  • 모듈러 지중아치 구조는 시공과정이 단순하며 강재와 콘크리트를 이용하여 시공 및 공용 중에 발생하는 단면력에 대하여 효과적으로 저항할 수 있는 구조로 제안되어 15m 이하의 지간에 대하여 3차원 구조해석 및 실험을 통하여 구조적 거동이 평가되었다. 일반적으로 지중아치와 터널 등의 구조해석의 경우 2차원이나 3차원 구조해석 방법이 적용될 수 있다. 하지만, 모듈러 지중아치 구조의 구조적 안전성 평가를 위하여 2차원이나 3차원 구조해석 방법을 적용할 경우 구조해석을 위한 모형화가 어렵고, 해석시간이 과도하게 오래 걸릴 수 있으므로, 모듈러 지중아치 구조의 설계과정에서 필요한 구조 안전성 및 토압 등을 고려한 구조해석 방법으로는 합리적이지 않을 수 있다. 또한, 사전에 결정된 단면이 적용가능한 지간에 대하여 모듈러 지중아치 구조를 구성하는 경우 지간과 하중조건에 따른 단면과 구조적 안전성만을 평가하는 것이 합리적일 수 있다. 따라서, 본 연구에서는 효율적인 구조 안전성 평가를 위하여 프레임 요소를 이용한 구조해석 모델을 제안하고, 2차원 구조해석모델과 프레임 요소를 이용한 간략해석모델의 구조해석 결과를 비교하였으며, 간략해석 방법을 이용하여 20m지간의 모듈러 지중아치구조의 구조적 안전성을 평가하였다.

모듈개념을 적용한 가변형 실내조명 디자인개발 (Design Development of Variable Interior Lighting Applying the Concept of Module)

  • 이승헌;김기수
    • 한국콘텐츠학회논문지
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    • 제18권7호
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    • pp.28-37
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    • 2018
  • 본 논문에서는 실내 인테리어에 적용 가능한 조명 디자인을 기본으로 생각하고 연구하였으며 나아가 근린공원에 설치될 공익시설물을 대상으로 공공디자인의 목적도 함께 연구하여 합리적 사용을 추구하는 모듈형 가변식 실내조명 제품디자인을 연구하고자 한다. 이러한 연구를 위하여 모듈의 기본적인 개념을 알 수 있는 선행연구 고찰과 실내디자인에 적용 가능한 조명과 실내에 대한 선행사례를 분석하였다. 이러한 분석을 토대로 본 연구에서는 모듈개념을 적용한 조명디자인의 새로운 컨셉을 도출을 위해 제품실무 개발을 위한 디자인 방향과 프로세스, 제품보관, 조립, 관리가 편리한 모듈 조립형 디자인을 제시하여 향후 조명디자인 개발에 관련된 합리적 유지관리 방향을 살펴보고 새로운 제품디자인개발에 반영할 수 있는 디자인 개발사례를 제시하였다. 또한 인지전략 프로세스를 통해 디자인을 진행하였으며 이러한 프로세스는 개념적 전략으로 실내환경 분석단계, 조명유지 보수단계, 가변형 메커니즘단계, 감성활성화 단계를 적용하여 연구를 진행하였다. 이러한 단계적특성은 디자인적인 조형적 아름다운과 접목시켜 MLD(Module Lamp Design) 전략을 제시하여 인간이 느낄 수 있는 공간에 대한 자유로운 적용을 모듈제품과 접목시키고 인간의 시각적접근과 바라보며 자유롭게 생각하는 개념적 가치를 담아 MLD인지전략 디자인 프로세스에 적용시켜 개발 하고자 하였다.

링크표지갱신 다수경로탐색 알고리즘 (K-th Path Search Algorithms with the Link Label Correcting)

  • 이미영;백남철;최대순;신성일
    • 대한교통학회지
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    • 제22권2호
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    • pp.131-143
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    • 2004
  • 최적경로 알고리즘에서 링크표지를 활용하면 도시가로망 상에 나타나는 유턴이나 피턴과 같은 주행했던 교차로를 다시 주행하는 통행에 대한 설명이 가능하다. 본 연구에서는 링크표지기법을 표지갱신기반 다수경로탐색알고리즘으로 확대하는 것이 목적이다. 이를 위해 도시가로망에서 발생하는 운전자의 합리적 통행행태를 링크기반으로 개념화하고, 이들 행태가 반영되도록 링크표지갱신 다경로 알고리즘을 제안하였다. 소규모 네트워크 테스트를 통하여 알고리즘의 수행과정과 결과의 적정성을 확인하였다. 대규모 네트워크 컴퓨터 수행을 통해 해의 퇴화현상을 파악하고 소수의 대안경로 정보제공에 활용 가능한 (K-1)차원 알고리즘을 제안하였다. 결론적으로 제안된 다수경로 알고리즘으로 링크표지기법이 제공하는 합리적 통행행태의 고려가 다수의 경로에도 가능해졌을 뿐만 아니라, 효율적인 대안경로 제공의 활용단계를 위해 한단계 전진되었다.

중국의 동북아 물류중심화 현황과 발전전략에 관한 연구 (A Study of China's Condition as the Logistics Hub of Northeast Asia and a Development Strategy)

  • 오문갑
    • 유통과학연구
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    • 제12권2호
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    • pp.95-103
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    • 2014
  • Purpose - Korea has a better geographical location than other nations in the Northeast Asian region. This means that Korea has an opportunity to become the center of international physical distribution in Northeast Asia. Korea should take advantage of this opportunity by exploring appropriate strategies to achieve this goal, assuming government willingness, with a view to capitalizing on the geographical advantage of the Korean peninsula and constructing a comprehensive physical distribution network system. If we prepare for this scenario, Korea could become the center of international physical distribution in Northeast Asia. Research design, data, and methodology - This study has the purpose of determining how shipping companies form partnerships with third-party logistics providers, and the relevant implications. The survey methods used were personal interview and a questionnaire distributed through e-mail, fax, mail, and telephone. A total of 600 questionnaires were distributed, out of which 285 were returned. Of the collected questionnaires, 10 were excluded because of insufficient content, leaving 275 to be used in the study as available valid samples. The data that was collected from these samples was analyzed using the data coating process and by employing a statistical package program. Results - Flexible policies, administration, and systems will be needed to create better business practices. In this dissertation, first and foremost, the results reveal that in order to become the center of Northeast Asian logistics, Korea must transition into a new paradigm based on the current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. Flexible policies, administration, and systems will be required to create better business practices. Domestic logistics corporations need to occupy a strategic logistics hub, create a logistics network, and activate value-added logistics business strategies by ensuring significant manpower and by building a logistics information system to strengthen their competitive edge, creating an improved system. Conclusions - In this dissertation, first and foremost, we point out that in order to become a center of North East Logistics, Korea should change to a new paradigm from the old one based on current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. More reasonable business laws, systems, and policies based on market-driven flexibility and transparency should be created. Moreover, social norms and rules should be reasonably established, to accomplish political and social security. Korea has to cultivate a culture of tolerance for foreign companies. This involves a change of paradigm for the development of the capital city and satellite cities. It will take a powerful task force or organization to plan and execute the vision that aims to meet these needs, accomplish the necessary goals, use the appropriate system effectively, and make Korea a key country in the field of Northeast Asian logistics.

비선형 연약지반을 고려한 약진에 의한 비탄성 응답스펙트럼 (Inelastic Response Spectra Due to the Weak Earthquakes Considering the Nonlinear Soft Soil Layer)

  • Kim, Yong-Seok
    • 한국지진공학회논문집
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    • 제7권4호
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    • pp.15-22
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    • 2003
  • 강진을 고려한 지진설계 규준은 약진지역에서는 불필요한 경제적 손실을 가져을 수 있고, 지반-구조물 상호작용을 고려한 성능기준 설계가 합리적인 지진설계를 위해서 중요하다는 것이 인식되었다. 이 연구에서는 연약지반 위에 놓인 단자유도계의 탄성, 비탄성 지진응답 해석을 지반의 비선형성을 고려하여 최대지진가속도를 0.07g와 0.11g로 조정한 11개 약진에 대해 수행하였다. 지진응답해석은 지반-구조물체계에 대해 유사 3차원 동적해석 프로그램으로 암반에 지진기록을 입력하여 한 단계에 일괄적으로 수행하였다. 연구 결과에 의하면 고정지반이나 선형지반을 가정한 지진응답 스펙트럼은 구조물-지반체계의 실제적인 거동을 보여주지 못하는 것으로 나타났으며, 합리적인 지진설계를 위해서는 지진규준에 정해진 일상적인 설계절차에 다라서 수행하는 것보다 다른 성질을 가진 여러 지반에 대해서 성능기준 지진설계를 수행하는 것이 필요하다. 약진을 받는 연약지반의 비선형성도 입력지진동을 증폭시켜 탄성, 비탄성 지진응답 스펙트럼에 심하게 영향을 미쳤으며, 그 현상은 특히 탄성 응답스펙트럼에서 두드러졌다.