• Title/Summary/Keyword: internal relation

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

  • Lee Sang-Ju;Lee Dong-Woo;Han Sang-Eul
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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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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The Analysis of Local Buckling Behavior for Steel Circular Tubes (국부좌굴을 동반하는 원형강관 부재의 복원력 특성)

  • Lee, Sang-Ju;Lee, Dong-Woo;Han, Sang-Eul
    • Proceeding of KASS Symposium
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    • 2006.05a
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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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A Study on Logistics Integration and Logistics Performance of Shipping Firms in International Logistics (국제물류에서 해운기업의 물류통합과 물류성과에 관한 연구)

  • Yun, Kwang-Woon;Ha, Myung-Shin;Bae, Hee-Sung
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.26
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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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Effect of Anti-Alzheimer's disease by Jeonmaedan in CT105-overexpressed SK-N-SH cell lines (CT105로 유도된 인간신경아세포종 세포주에서 전매단의 항치매 효과)

  • Song Ho-Sang;Park Chi-Sang;Park Chang-Gook
    • Herbal Formula Science
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    • v.11 no.2
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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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    • v.54 no.4
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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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    • v.13 no.3
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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.

Analysis of Deformation Localization of Void Material using Nolocal Constitutive Relation (I) (비국소형 구성식을 이용한 보이드 재료의 변형 국소화 거동의 해석(I))

  • 김영석;최홍석;임성언
    • Transactions of Materials Processing
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    • v.9 no.1
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    • pp.59-65
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    • 2000
  • Most studies of failure analysis in ductile metals have been based on the classical plasticity theory using the local constitutive relations. These frequently yields a physically unrealistic solution, in which a numerical prediction of the onset of a deformation localization shows an inherent mesh-size sensitivity. A one way to remedy the spurious mesh sensitivity resulted in the unreasonable results is to incorporate the non-local plasticity into the simulation model, which introduce an internal (material) length-scale parameter into the classical constitutive relations. In this paper, a non-local version of the modified Gurson constitutive relation has been introduced into the finite element formulation of the simulation for plane strain compression of the visco elastic-plastic void material. By introducing the non-local constitutive relations we could successfully removed the inherent mesh-size sensitivity for the prediction of the deformation localization. The effects of non-local constitutive relation are discussed in terms of the load-stroke curve and the strain distributions accross the shear band.

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

  • Wang, C.B.;Lim, S.J.;Park, Y.B.
    • Transactions of Materials Processing
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    • v.15 no.7 s.88
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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.

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

  • Lee, Han-Gu;Jung, Sung-Gi;Lee, Hyung-Koo
    • The Journal of Internal Korean Medicine
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    • v.11 no.1
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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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Spin-Rotation Interaction in Polyatomic Molecules in the Presence of Internal Rotation (內部廻轉存在時의 多原子分子에서의 스핀-廻轉相互作用)

  • Lee Jo W.
    • Journal of the Korean Chemical Society
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    • v.20 no.5
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    • pp.364-373
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    • 1976
  • A magnetic nucleus located on an internal rotor in a polyatomic molecule can interact with the magnetic fields arising from internal rotation as well as end-over-end molecular rotation. In this paper the spin-rotation coupling Hamiltonian for a nuclear spin on a symmetrical internal rotor in a polyatomic molecule is derived. The derived spin-rotation Hamiltonian turns out to be composed of the two parts: the spin-over-all-rotation interaction and the spin-internal-rotation interaction. The relation between the spin-rotation coupling tensor and the magnetic shielding effect is also investigated.

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