• 제목/요약/키워드: internal relation

검색결과 785건 처리시간 0.027초

반복 축하중을 받아 국부좌굴을 수반하는 원형강관 부재의 복원력 특성 (The Behavior of Local Buckling for Steel Circular Tubes Subject to Cyclic Axial Loads)

  • 이상주;이동우;한상을
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.347-354
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    • 2006
  • In this paper, we work with steel circular tubes and propose analysis model which can consider local buckling that it has an effect on failure of steel structures and induce the relation between loading and deformation. First of all, in respect to axial symmetry local buckling, which is simplest case, elasto-plastic behavior acting only axial loads is object Therefore, it suggests analysis model for axial symmetry local buckling. And that is explainable the process from increasing internal force to decreasing passing maximum internal force. Besides, we induce the relation between the axial force and axial deformation.

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국부좌굴을 동반하는 원형강관 부재의 복원력 특성 (The Analysis of Local Buckling Behavior for Steel Circular Tubes)

  • 이상주;이동우;한상을
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2006년도 춘계 학술발표회 논문집 제3권1호(통권3호)
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    • pp.73-80
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    • 2006
  • In this paper, we work with steel circular tubes and propose analysis model which can consider local buckling that it has an effect on failure of steel structures and induce the relation between loading and deformation. First of all, in respect to axial symmetry local buckling, which is simplest case, elasto-plastic behavior acting only axial loads is object. Therefore, it suggests analysis model for axial symmetry local buckling. And that is explainable the process from increasing internal force to decreasing passing maximum internal force. Besides, we induce the relation between the axial force and axial deformation.

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국제물류에서 해운기업의 물류통합과 물류성과에 관한 연구 (A Study on Logistics Integration and Logistics Performance of Shipping Firms in International Logistics)

  • 윤광운;하명신;배희성
    • 무역상무연구
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    • 제26권
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    • pp.143-172
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    • 2005
  • The biggest exchange of international environment of shipping logistics in 21 century should appear ultra-mega container ships on the shipping market. The competitive trend of large size container ship was based on economics of scale among the international shipping business. In the environment, shipping firms consider the integration of freight forwarder and shipper in the international logistics process. The aims of this research analyse a relation between the environment uncertainty and logistics information system(LIS) and the integration and resolve the integration and its impact on logistics performance. The research methodology of this research analyse structural equation modeling on the relation of variables. The results of research are as follows. First, Environmental uncertainty significantly influences the internal integration and the external integration. Second, LIS has an influence on the logistics integration by providing the foundation for LIS utilization in international logistics process. Third, the internal integration significantly influences a logistics performance, which implies that firms should promote interaction and collaboration through internal process integration to achieve logistics performance as the logistical cost and service. But the external integration is not significantly a logistics performance.

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CT105로 유도된 인간신경아세포종 세포주에서 전매단의 항치매 효과 (Effect of Anti-Alzheimer's disease by Jeonmaedan in CT105-overexpressed SK-N-SH cell lines)

  • 송호상;박치상;박창국
    • 대한한의학방제학회지
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    • 제11권2호
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    • pp.95-110
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    • 2003
  • Alzheimer's disease(AD) is a geriatric dementia that is widespread in old age. In the near future AD will be the biggest problem in public health service. Although a variety of oriental prescriptions in study Jeonmaedan have been traditionally utilized for the treatment of AD, their pharmacological effects and action mechanisms have not yet fully elucidated. It has been widely believed that A${\beta}$ peptide devided from APP causes apoptotic neurotoxicity in AD brain. However, recent evidence suggests that CTl05(carboxy terminal 105 amino acid peptide fragment of APP) may be an important factor causing neurotoxicity in AD. In addition, AD is one of brain degeneration disease. So we studied on herbal medicine that have a relation of brain degeneration. In Oriental Medicine, Jeonmaedan has been used for disease in relation to brain degeneration. As the result of this study, in Jeonmaedan the apoptosis in the nervous system is inhibited, the repair against the degerneration of SK-N-SH cell lines by CT105 expression is promoted. So Jeonmaedan may be beneficial for the treatment of AD.

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Direct kinematic method for exactly constructing influence lines of forces of statically indeterminate structures

  • Yang, Dixiong;Chen, Guohai;Du, Zongliang
    • Structural Engineering and Mechanics
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    • 제54권4호
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    • pp.793-807
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    • 2015
  • Constructing the influence lines of forces of statically indeterminate structures is a traditional issue in structural engineering and mechanics. However, the existing kinematic method for establishing these force influence lines is an indirect or mixed approach by combining the force method with the theorem of reciprocal displacements, which is yet inconsistent with the kinematic method for statically determinate structure. This paper proposes the direct kinematic method in conjunction with the load-displacement differential relation for exactly constructing influence lines of reaction and internal forces of indeterminate structures. Firstly, through applying the principle of virtual displacement, the formula for influence lines of reaction and internal forces of indeterminate structure via direct kinematic method is derived based on the released structure. Then, a computational approach with a clear concept and unified procedure as well as wide applicability based on the load-displacement differential relation of beam is suggested to achieve conveniently the closed-form expression of force influence lines, and exactly draw them. Finally, three representative examples for constructing force influence lines of statically indeterminate beams and frame illustrate the superiority of the proposed method.

Musculoskeletal Model for Assessing Firefighters' Internal Forces and Occupational Musculoskeletal Disorders During Self-Contained Breathing Apparatus Carriage

  • Wang, Shitan;Wang, Yunyi
    • Safety and Health at Work
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    • 제13권3호
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    • pp.315-325
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    • 2022
  • Background: Firefighters are required to carry self-contained breathing apparatus (SCBA), which increases the risk of musculoskeletal disorders. This study assessed the newly recruited firefighters' internal forces and potential musculoskeletal disorders when carrying SCBA. The effects of SCBA strap lengths were also evaluated. Methods: Kinematic parameters of twelve male subjects running in a control condition with no SCBA equipped and three varying-strapped SCBAs were measured using 3D inertial motion capture. Subsequently, motion data and predicted ground reaction force were inputted for subject-specific musculoskeletal modeling to estimate joint and muscle forces. Results: The knee was exposed to the highest internal force when carrying SCBA, followed by the rectus femoris and hip, while the shoulder had the lowest force compared to the no-SCBA condition. Our model also revealed that adjusting SCBA straps length was an efficient strategy to influence the force that occurred at the lumbar spine, hip, and knee regions. Grey relation analysis indicated that the deviation of the center of mass, step length, and knee flexion-extension angle could be used as the predictor of musculoskeletal disorders. Conclusion: The finding suggested that the training of the newly recruits focuses on the coordinated movement of muscle and joints in the lower limb. The strap lengths around 98-105 cm were also recommended. The findings are expected to provide injury interventions to enhance the occupational health and safety of the newly recruited firefighters.

중공축 내접 스플라인 성형을 위한 설계변수의 영향 (Effect of the Design Parameter for Internal Spline Forming Using the Tube)

  • 왕창범;임성주;박용복
    • 소성∙가공
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    • 제15권7호
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    • pp.512-517
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    • 2006
  • In this paper, the cold extrusion process for internal spline forming using a thin and long tube has been analyzed by using a rigid plastic finite element code. The internal spline consists of 10 tooths. The cold extrusion process has been focused on the comparisions of load-stroke relation and filling states of the teeth according to design parameters. The design parameters involve extrusion ratio, extrusion angle and friction factor. The internal spline forming can cause the buckling and folding during the cold extrusion process because of using a thin and long tube. The optimum design parameters have been obtained through rigid-plastic finite elements analysis. The extrusion ratio and extrusion angle have great effects on the deformation characteristics of the cold extrusion process.

폐(肺)와 피부(皮膚)의 관계(關係)에 대(對)한 문헌적(文獻的) 고찰(考察) (The investigation of literature about relation of lung and skin)

  • 이한구;정승기;이형구
    • 대한한방내과학회지
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    • 제11권1호
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    • pp.141-146
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    • 1990
  • The skin is related the lung as follows ; 1. The lung control skin and give a nutrition to skin. The skin and hair 'hab' (合) the lung. 2. As a damage of lung is a damage of skin, skin and hair 'chi-lag' (聚落) 3. A defensive energy of lung give a nutrition to skin, and strengthen the body surface. 4. Dryness damage the lung, and so damage the skin. According to the above findings, we know the body surface are closely related to the lung functionally.

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內部廻轉存在時의 多原子分子에서의 스핀-廻轉相互作用 (Spin-Rotation Interaction in Polyatomic Molecules in the Presence of Internal Rotation)

  • 이조웅
    • 대한화학회지
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    • 제20권5호
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    • pp.364-373
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    • 1976
  • 多原子分子內의 內部廻轉子上에 있는 磁氣核은 分子의 全體廻轉으로 因하여 생기는 磁氣場뿐만 아니라 內部廻轉에 基因하는 磁氣場과도 相互作用할 수 있다. 이 論文에서는 多原子分子內의 內部廻轉子上에 있는 核스핀에 對한 스핀-廻轉相互作用 Hamiltonian을 誘導하였다. 誘導된 Hamiltonian은 스핀과 全體廻轉間의 相互作用을 나타내는 部分 및 스핀과 內部廻轉間의 相互作用을 나타내는 部分과의 合으로 이루어져 있음을 밝혔다. 스핀-廻轉相互作用 tensor와 磁氣的 가리움效果 間의 關係도 또한 調査하였다.

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Two-domain 경계 요소법을 이용한 해양 내부파의 수치적 재현 (Numerical Analysis of Internal Waves in Two-layer Fluids by a Two-domain Boundary Element Method)

  • 구원철;김미근
    • 한국해양공학회지
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    • 제23권4호
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    • pp.6-11
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    • 2009
  • In this study, the internal waves in two-density layered fluids were analyzed using the Numerical Wave Tank (NWT) technique in the frequency domain. The NWT is based on a two-domain Boundary Element Method with the potential fluids using the whole-domain matrix scheme. From the mathematical solution of the two-domain boundary integral equation, two different wave modes could be classified: a surface wave mode and an internal wave mode, and each mode were shown to have a wave number determined by a respective dispersion relation. The magnitudes of the internal waves against surface waves were investigated for various fluid densities and water depths. The calculated results are compared with available theoretical data.