• Earthquakes and Structures
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• 제9권1호
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• pp.127-143
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• 2015

In conventional seismic design, structures are assumed to be fixed at the base. To reduce the impact of earthquake loading, while at the same time providing an economically feasible structure, minor damage is tolerated in the form of controlled plastic hinging at predefined locations in the structure. Uplift is traditionally not permitted because of concerns that it would lead to collapse. However, observations of damage to structures that have been through major earthquakes reveal that partial and temporary uplift of structures can be beneficial in many cases. Allowing a structure to move as a rigid body is in fact one way to limit activated seismic forces that could lead to severe inelastic deformations. To further reduce the induced seismic energy, slip-friction connectors could be installed to act both as hold-downs resisting overturning and as contributors to structural damping. This paper reviews recent research on the concept, with a focus on timber shear walls. A novel approach used to achieve the desired sliding threshold in the slip-friction connectors is described. The wall uplifts when this threshold is reached, thereby imparting ductility to the structure. To resist base shear an innovative shear key was developed. Recent research confirms that the proposed system of timber wall, shear key, and slip-friction connectors, are feasible as a ductile and low-damage structural solution. Additional numerical studies explore the interaction between vertical load and slip-friction connector strength, and how this influences both the energy dissipation and self-centring capabilities of the rocking structure.

• Asian-Australasian Journal of Animal Sciences
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• 제25권5호
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• pp.701-707
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• 2012

Immune stress is the loss of immune homeostasis caused by external forces. The purpose of this experiment was to investigate the effects of immune stress on the growth performance, small intestinal enzymes and peristalsis rate, and mRNA expression of nutrient transporters in broiler chickens. Four hundred and thirty-two 1-d-old broilers (Cobb500) were randomly assigned to four groups for treatment; each group included nine cages with 12 birds per cage. Group 1 = no vaccine (NV); Group 2 = conventional vaccine (CV); group 3 = lipopolysaccharide (LPS)+conventional vaccine (LPS); group 4 = cyclophosphamide (CYP)+conventional vaccine (CYP). The results demonstrated that immune stress by LPS and CYP reduced body weight gain (BWG), feed intake (FI), small intestine peristalsis rate and sIgA content in small intestinal digesta (p<0.05). However, the feed conversion ratio (FCR) remained unchanged during the feeding period. LPS and CYP increased intestinal enzyme activity, relative expression of SGLT-1, CaBP-D28k and L-FABP mRNAs (p<0.05). LPS and CYP injection had a negative effect on the growth performance of healthy broiler chickens. The present study demonstrated that NV and CV could improve growth performance while enzyme activity in small intestine and relative expression of nutrient transporter mRNA of NV and CV were decreased in the conditions of a controlled rational feeding environment. It is generally recommended that broilers only need to be vaccinated for the diseases to which they might be exposed.

• 대한조선학회지
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• 제22권3호
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• pp.9-18
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• 1985

The numerical calculation for solving boundary-value problem related to potential flows with a free surface is carried out by application of the localized finite element method. Only forced motion of 2-D body in infinitely deep fluid is considered, although this schemes is equally applicable to any first order time-harmonic problems of similar nature. The infinite domain of the fluid is separated into the inner flow field and the outer flow field with common inter-surface boundary. The finite element method is applied to obtain the solution in the inner flow field and the Green functions are utilized to represent the solution in the outer flow field. At the inter-surface boundary, the continuity of the value of potential and the normal derivative of the potential(i.e. matching condition) is conserved. The present method has better computational efficiency than the previous LFEM and the integral equation method of Frank. This enhanced computational efficiency is presumably due to the fact that the present method gives a symmetric coefficient matrix and requires less computational time in calculating the influence coefficient matrix of Green function than the integral equation method. And the irregular frequency desen't exist because the uniqueness of the solution is assured by the such that the exact free surface condition is satisfied on the boundary of the localized finite element region(i.e. inner region). As an example of the above method, the hydrodynamic forces for the circular cylinder and the rectangular cylinders are calculated. In the computed results, the small number of singularity distribution segments($3{\sim}6$) give good result relative to Ursell's and Vugts'.

• Journal of Ship and Ocean Technology
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• 제1권1호
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• pp.35-47
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• 1997

The consequences associated with ships running aground depend very much on the soil characteristics of the sea bed and the geometrical shape of the ship bow. The penetration into the sea bed depends on these factors and the penetration is an important factor for the ship motion because it influences the ship heave and pitch motions as well as the friction between the ship and the soil. In this paper a rational calculation model is presented for the sea bed soil reaction forces on the ship bottom. The model is based on the assumption that the penetration of the ship bow generates a flow of pore water through the grain skeleton of the soil. The flow is governed by Darcy\`s law and it is driven by the pressure of the pore water at the bow. In addition to this pore water pressure, the bow is subjected to the effective stresses in the grain skeleton at the bow surface. These stresses are determined by the theory of frictional soils in rupture. Frictional stresses on the bow surface are assumed to be related to the normal pressure by a simple Coulomb relation. The total soil reaction as a function of velocity and penetration is found by integration of normal pressure and frictional stresses over the surface of the bow. The analysis procedure is implemented in a computer program for time domain rigid body analysis of ships running aground and it is verified in the paper through a comparison of calculated stopping lengths, effective coefficients of friction, and sea bed penetrations with corresponding experimental results obtained by model tests as well as large, scale tests.

• Wind and Structures
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• 제20권2호
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• pp.213-236
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• 2015

For high-speed railways (HSR) in wind prone regions, wind barriers are often installed on bridges to ensure the running safety of trains. This paper analyzes the effect of wind barriers on the running safety of a high-speed train to cross winds when it passes on a bridge. Two simply-supported (S-S) PC bridges in China, one with 32 m box beams and the other with 16 m trough beams, are selected to perform the dynamic analyses. The bridges are modeled by 3-D finite elements and each vehicle in a train by a multi-rigid-body system connected with suspension springs and dashpots. The wind excitations on the train vehicles and the bridges are numerically simulated, using the static tri-component coefficients obtained from a wind tunnel test, taking into account the effects of wind barriers, train speed and the spatial correlation with wind forces on the deck. The whole histories of a train passing over the two bridges under strong cross winds are simulated and compared, considering variations of wind velocities, train speeds and without or with wind barriers. The threshold curves of wind velocity for train running safety on the two bridges are compared, from which the windbreak effect of the wind barrier are evaluated, based on which a beam structure with better performance is recommended.

• 복식
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• 제65권8호
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• pp.64-76
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• 2015

Gilles Deleuze highly evaluated Baroque as the expression body that implements the fold theory, a philosophical thinking about the nature of beings. This can be seen as a meaning that Baroque implements the essence of the world, or the power constituting that essence. In addition, the beauty of Baroque focuses on 'New Harmony' the sum of partial forms caused by each element, and not Platonic harmony. he evaluated the aesthetic of Baroque costume as 'acquisition of liberation and autonomy', 'derived force from infinite spiritual forces'. This study analyzed the contents of the Aesthetic of Baroque costume based on the reviewed Deleuze's folding theory, Baroque aesthetics, and views of Baroque costume. As a result, it inferred the aesthetic of Baroque costume into four types, which are as follows: open structural openness, overlapping structural dynamics, integrated structural diversity, and relationship structural integrity. This study analyzed the aesthetic of Baroque costume based on Deleuze's philosophical thinking. The analysis showed that its aesthetics, which focused on "New Harmony", created energy of life and a venue for expression of power, as the aesthetics eliminated the prejudice of complexity and excessive decoration. In addition, Baroque costume is not the simple historical costume of the past. Instead, it is one of power and spirit, still existing in modern fashion. Baroque costume's formativeness and Paradigm can be said to provide the creative principle important for modern fashion because the aesthetics implemented in Baroque costume accepts free spirit, new challenge, difference and diversity, and is similar to the spirit pursued by modern art and fashion.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.499-504
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• 2001

A validation of a 3D CFD model for predicting local subcooling of moderator in the vicinity of calandria tubes in a CANDU reactor is performed. The small scale moderator experiments performed at Sheridan Park Experimental Laboratory(SPEL) in Ontario, Canada[1] is used for the validation. Also a comparison is made between previous CFD analyses based on 2DMOTH and PHOENICS, and the current model analysis for the same SPEL experiment. For the current model, a set of grid structures for the same geometry as the experimental test section is generated and the momentum, heat and continuity equations are solved by CFX-4.3, a CFD code developed by AEA technology. The matrix of calandria tubes is simplified by the porous media approach. The standard $k-\varepsilon$ turbulence model associated with logarithmic wall treatment and SIMPLEC algorithm on the body fitted grid are used and buoyancy effects are accounted for by the Boussinesq approximation. For the test conditions simulated in this study, the flow pattern identified is a buoyancy-dominated flow, which is generated by the interaction between the dominant buoyancy force by heating and inertial momentum forces by the inlet jets. As a result, the current CFD moderator analysis model predicts the moderator temperature reasonably, and the maximum error against the experimental data is kept at less than $2.0^{\circ}C$ over the whole domain. The simulated velocity field matches with the visualization of SPEL experiments quite well.

• 한국문헌정보학회지
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• 제42권1호
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• pp.335-358
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• 2008

Dewey가 1873년에 제안한 'Three Genetic Paper'은 '시스템(문헌분류법)의 이점(The Merits of the system)' '도서관 분류법시스템, 즉 구조와 사용법(Library Classification system)' 그리고 '우리 도서관에서의 특별적용(Its Special Adaptation to our Library)'이다. 3개의 기원논문은 전체가 1.800여개의 단어로 구성되어 있는데, 그중 절반이 '시스템(문헌분류법)의 이점'이며, 520개 단어가 '도서관 분류법시스템, 즉 구조와 사용법'이며, 그 다음으로 '우리 도서관에서의 특별적용(Its Special Adaptation to our Library)'에 관한 것이 가장 짧아서, 350개 정도로 정리되었다. 'Three Genetic Papers'의 내용은 1876년에 발행된 DDC초판의 서문을 형성하는데 그대로 반영되어 분류법 이론의 근간이 되었다.

• 국제물리치료학회지
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• 제2권1호
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• pp.244-250
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• 2011

The purpose of this study is to investigate whether there are differences in physique characteristics between the excellent domestic player groups in each sport player's, to prevent epidemiologic damage of musculoskeletal system and to provide fundamental data to improve performances for players. This study has performed for total 60 student players from Y University in Yongin, Gyeonggi-do, consists of 20 Kendo players, 20 Judo players and 20 Taekwondo players. We measured the length and circumference of arm, leg, body using Martin anthropometer to collect the data for 3 groups. There was significant difference in lower left arm length between player groups(p<.01), and Kendo players' right side femoral were longer than other 2 groups for leg length measurement(p<.01). Judo players' circumference for right/left stretched arm/bent upper arm were thicker than other 2 groups(p<.01). Taekwondo players' chest circumference were smaller than other 2 groups(p<.01), and Taekwondo players' right/left femoral circumference were thinner than other 2 groups(p<.05). From this study, it was found that there are physique characteristics differences between the Kendo, Judo and Taekwondo player groups. This indicates that repeated exercise for each sport player causes physique change, and it may cause epidemiologic damage of musculoskeletal system. It is recommended to perform balancing exercise prior to main exercise.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.311-314
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• 2006

This paper concerns about total dynamic analysis of integrated mining system. This system consists of vertical steel pipe, intermediate buffer station, flexible pipe and self-propelled miner. The self-propelled miner and buffer are assumed as rigid-body of 6-dof. Discrete models of vertical steel pipe and flexible pipe are adopted, which are obtained by means of lumped-parameter method. The motion of mining vessel is not considered. Instead, the motion of mining vessel is taken into account in form of various boundary conditions (e.g. forced excitation in slow motion and/or fast oscillation and so on). A terramechanics model of extremely soft cohesive soil is applied to the self-propelled miner. The hydrodynamic forces and moments are included in the dynamic models of vehicle and lifting pipe system. Hinged and fixed constraints are used to define the connections between sub-systems (vertical steel pipe, buffer, flexible pipe, miner). Equations of motion of the coupled model are derived with respect to the each local coordinates system. Four Euler parameters are used to express the orientations of the sub-systems. To solve the equations of motion of the total dynamic model, an incremental-iterative formulation is employed. Newmark-b method is used for time-domain integration. The total dynamic responses of integrated mining system are investigated.