• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1303-1313
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• 2013

In this study, the reference values for the internal forces of the rail supports caused by a wheel load, a unit vertical displacement, a unit end rotation in examination of the serviceability of concrete slab track bridge were obtained. In analysis, the analysis models of which the rail was continuously and discretely supported by elastic springs were used. The internal forces of the rail supports from the analysis were compared with the results provided in the DS 804 regulations and agreed with well. In addition, the effects of the space between the rail supports and the stiffness of fastener on the internal forces of the rail supports were investigated.

• Asia pacific journal of information systems
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• v.5 no.2
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• pp.199-226
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• 1995

This study is an empirical research in order to clarify whether or not the correlation between the satisfaction of users that is the performance measurement factor and the following three:(1) the attitude of users as an individual characteristic, (2) the supports of organization as an organizational characteristic, (3) the routine degree of jobs as an job characteristic, is the same as the previous study results. In addition, another empirical research was done to make clear how organizational supports and routine degree change the attitude and satisfaction of users. This study put a particular emphasis on the moderating effect because the study of this issue has not been done in any previous research. 38 corporations, whose computerization has already been made to some extent and who are listed on the stock exchange market as a leader group, was selected for research, given some hypotheses on the basis of theoretical studies. As results of this empirical study, first, the supports of organization and the routine degree of jobs changed the attitude of users, which was the same as the previous studies. Moreover, the supports of organization, the routine degree of jobs and the attitude of users had an influence on the satisfaction of users. Second, in respect of the correlation between the attitude of users and the satisfaction of users, the routine degree of jobs showed a moderating effect, but the organization supports did not show any moderating effect.

• Advances in concrete construction
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• v.9 no.6
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• pp.557-568
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• 2020

In this study, the impact of ring supports around the shell circumferential has been examined for their various positions along the shell axial length using Rayleigh-Ritz formulation. These shells are stiffened by rings in the tangential direction. For isotropic materials, the physical properties are same everywhere where the laminated and functionally graded materials, they vary from point to point. Here the shell material has been taken as functionally graded material. The influence of the ring supports is investigated at various positions. These variations have been plotted against the locations of ring supports for three values of length-to-diameter ratios. Effect of ring supports with middle layer thickness is presented using the Rayleigh-Ritz procedure with three different conditions. The influence of the positions of ring supports for clamped-clamped is more visible than simply supported and clamped-free end conditions. The frequency first increases and gain maximum value in the midway of the shell length and then lowers down. The Lagrangian functional is created by adding the energy expressions for the shell and rings. The axial modal deformations are approximated by making use of the beam functions. The comparisons of frequencies have been made for efficiency and robustness for the present numerical procedure. Throughout the computation, it is observed that the frequency behavior for the boundary conditions follow as; clamped-clamped, simply supported-simply supported frequency curves are higher than that of clamped-simply curves. To generate the fundamental natural frequencies and for better accuracy and effectiveness, the computer software MATLAB is used.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.45-55
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• 2012

The road luminaires have been treated as subsidiary electric apparatuses in the road although they are indispensable facilities which people use the road safely. Because of this misunderstanding, there are not many researches on luminaire supports against the wind loads. Therefore, a typhoon has overturned or damaged many luminaire supports without having sufficient structural safeties. The purpose of this study is to review the current design criteria and to suggest the improvement of design methods based on the structural safety and compatible with the site conditions of luminaire supports. The stress concentration around the inspection hole, which causes the collapse of luminaire supports, is analyzed and stress reduction method is suggested with the improved design methods.

• Nuclear Engineering and Technology
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• v.43 no.5
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• pp.447-458
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• 2011

This paper proposes an approximated contact force model to identify the nonlinear behavior of a fuel rod with gap supports; also, the numerical prediction of interfacial forces in the mechanical contact of fuel rods with gap supports is studied. The Newmark integration method requires the current status of the contact force, but the contact force is not given a priori. Taylor's expansion can be used to predict the unknown contact force; therefore, it should be guaranteed that the first derivative of the contact force is continuous. This work proposes a continuous and differentiable contact force model with the ability to estimate the current state of the contact force. An approximated convex and differentiable potential function for the contact force is described, and a variational formulation is also provided. A numerical example that considers the particularly stiff supports has been studied, and a fuel rod with hardening supports was also examined for a realistic simulation. An approximated proper solution can be obtained using the results, and abrupt changes from the contacting state to non-contacting state, or vice versa, can be relieved. It can also be seen that not only the external force but also the developed contact force affects the response.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.382-390
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• 2015

Poly(methyl methacrylate) (PMMA) supports and amine additives were investigated to adsorb $CO_2$. PMMA supports were fabricated by using different ratio of pore forming agents (porogen) to control the BET specific surface area, pore volume and distribution. Toluene and xylene are used for porogens. Supported amine sorbents were prepared by wet impregnation of tetraethylenepentamine (TEPA) on PMMA supports. So we could identify the effect of the pore structure of supports and the quantity of impregnated TEPA on the adsorption capacity. The increased amount of toluene as pore foaming agent resulted in the decreased average pore diameter and the increased BET surface area. Polymer supports with huge different pore distribution could be fabricated by controlling the ratio of porogen. After impregnation, the support with micropore structure is supposed the pore blocking and filling effect so that it has low $CO_2$ capacity and kinetics due to the difficulty of diffusing. Macropore structure indicates fast adsorption capacity and low influence of amine loading. In case of support with mesopore, it has high performance of adsorption capacity and kinetics. So high surface area and meso-/macro- pore structure is suitable for $CO_2$ capture.

• Structural Engineering and Mechanics
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• v.52 no.5
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• pp.997-1017
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• 2014

According to the structure characteristics of the non-uniform beam bridge, a practical model for calculating the vibration equation of the non-uniform beam bridge is given and the application scope of the model includes not only the beam bridge structure but also the non-uniform beam with added masses and elastic supports. Based on the Bernoulli-Euler beam theory, extending the application of the modal perturbation method and establishment of a semi-analytical method for solving the vibration equation of the non-uniform beam with added masses and elastic supports based is able to be made. In the modal subspace of the uniform beam with the elastic supports, the variable coefficient differential equation that describes the dynamic behavior of the non-uniform beam is converted to nonlinear algebraic equations. Extending the application of the modal perturbation method is suitable for solving the vibration equation of the simply supported and continuous non-uniform beam with its arbitrary added masses and elastic supports. The examples, that are analyzed, demonstrate the high precision and fast convergence speed of the method. Further study of the timesaving method for the dynamic characteristics of symmetrical beam and the symmetry of mode shape should be developed. Eventually, the effects of elastic supports and added masses on dynamic characteristics of the three-span non-uniform beam bridge are reported.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4557-4563
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• 2012

The purpose of this study is to suggest the criteria to public welfare service support for improving life quality of the haenyeo (female divers) through analyzing public welfare services and desires of the haenyeo in Jeju, Busan, and Tongyeong. Accordingly, research period was set from May 11 to June 21, 2010. The haenyeo in each region of Jeju, Yeongdo-gu (Busan), Tongyeong-si were selected as subjects. Recording of interviewing methods was used to recognize current status of public welfare. We analyzed by comparing desires of the haenyeo to public welfare services by dividing them economically, medically, educationally, and culturally. As a result of researching public welfare services to the haenyeo in each region, supports for protection of diving, growing area, public welfare service for aged diving haenyeo, and medical service were conducted. Tewak protecting net, Seonjinji visiting, and welfare facilities are supported in Busan-si but there is no support in Tongyeong-si. Therefore, desires of the haenyeo to such public welfare services are as followings: First, the desires of the haenyeo in Jeju to economic supports are indicated as supports for haenyeo experience spot, diving suit, and overseas visiting. To educational supports, it is indicated as supports for identity education, diving disease prevention education, and foreign language education. To cultural supports, it is indicated as supports for installation of welfare hall and exchange visit to foreign haenyeo culture. Second, in Busan, there were desires to establish changing room and fishery sales lot and to support diving suit as for economic supports, desires to support diving disease and medical benefits as for medical supports, desires to education of diving skill as for educational supports, and desires to establish welfare hall and haenyeo museum as for cultural supports. Third, in Tongyeong where public welfare services to the haenyeo are very poor, there were desires to support diving suit and to support changing room as for economic supports, as same as in Busan, desires to support diving disease and medical benefits as for medical supports.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.125-130
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• 2002

This paper investigates the dynamic characteristics of a beam axially moving over multiple elastic supports. The spectral element matrix is derived first for the axially moving beam element and then it is used to formulate the spectral element matrix for the moving beam element with an interim elastic support. The moving speed dependance of the eigenvalues is numerically investigated by varying the applied axial tension and the stiffness of the elastic supports. Numerical results show that the fundamental eigenvalue vanishes first at the critical moving speed to generate the static instability.

• Journal of the Korean Ceramic Society
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• v.31 no.4
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• pp.359-366
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• 1994

Tow types of supports were made using $\alpha$-Al2O3 powder and optimum conditions to prepare for supports were provided. Sol solution for coating was synthesized by sol-gel method with aluminum isopropoxide. Supports were coated and heat-treatemented, where the thickness of coating layer was controlled by dipping time. Flux and permeability of alumina membrane were measured by liquid and gas filtration apparatus and these were compared with the provided model. It was confirmed that the coating was done very well without micro~crack and defect.