• Steel and Composite Structures
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• v.25 no.6
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• pp.693-704
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• 2017

In this research, a simple hyperbolic shear deformation theory is developed and applied for the bending, vibration and buckling of powerly graded material (PGM) sandwich plate with various boundary conditions. The displacement field of the present model is selected based on a hyperbolic variation in the in-plane displacements across the plate's thickness. By splitting the deflection into the bending and shear parts, the number of unknowns and equations of motion of the present formulation is reduced and hence makes them simple to use. Equations of motion are obtained from Hamilton's principle. Numerical results for the natural frequencies, deflections and critical buckling loads of several types of powerly graded sandwich plates under various boundary conditions are presented. The accuracy of the present formulation is demonstrated by comparing the computed results with those available in the literature. As conclusion, this theory is as accurate as other theories available in the literature and so it becomes more attractive due to smaller number of unknowns.

• Journal of the Korean Institute of Educational Facilities
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• v.14 no.4
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• pp.114-119
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• 2007

• Journal of the korean Society of Automotive Engineers
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• v.24 no.3
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• pp.8-13
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• 2002

• The monthly packaging world
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• s.294
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• pp.82-89
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• 2017

• Journal of the Korean Society of Marine Environment & Safety
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• v.4 no.2
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• pp.43-52
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• 1998

Generally, the navigational safety of a ship under various loading conditions is evaluated by a loading manual. However, the loading manual handles only statical factors such as weight and buoyancy of ship without including any wave conditions. Practically ship's safety is much concerned with the occurrences on the rough sea as propeller racing, rolling, deck wetness, vertical acceleration, lateral acceleration, slamming and so on. The purpose of this paper is to present a synthetic and practical evaluation method of navigational safety using the integrated seakeeping performance index(ISPI) under loading conditions of ship in seaways. The method is calculated by means of the ISPI by measuring only vertical acceleration. Judgement of dangerousness is carried out for four lading conditions : homogeneous full loaded, half loaded, heavy ballast loaded, and normal ballast loaded conditions. In developing the practical evaluation system of navigational safety, it is useful to solve the difficulties in measuring factors by sensors. And by applying the evaluation diagrames, navigators are able to avoid dangerousness by keeping away of the danger encountering angle of wave direction which the diagram shows.

• Structural Engineering and Mechanics
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• v.74 no.5
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• pp.577-588
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• 2020

A unified solution is presented for the buckling analysis of rectangular laminated composite plates with elastically restrained edges. The plate is subjected to biaxial in-plane compression, and the boundary conditions are simulated by employing uniform distribution of linear and rotational springs at all edges. The critical values of buckling loads and corresponding modes are calculated based on classical lamination theory and using the Ritz method. The deflection function is defined based on simple polynomials without any auxiliary function. The verifications of the current study are carried out with available combinations of classic boundary conditions in the literature. Through parametric study with a wide range of spring factors with some classical as well as some not classical boundary conditions, competency of the present model of boundary conditions is proved.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.75-80
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• 2009

The present paper focuses on the analysis of aero-acoustics characteristic by several boundary conditions. In this simulation, a high-order and high-resolution numerical schemes are used for the accurate computation of compressible flow with several boundary conditions including characteristic boundary conditions as well as extrapolation and zonal characteristic boundary condition. These boundary conditions are applied to the computation of two dimensional circular cylinder flows with Mach number of 0.3 and Reynolds number of 400. The computation results are validated with measurement datum and other computation results for the Strouhal frequency of vortex shedding, the mean drag coefficient and root-mean-square lift for the unsteady periodic flow regime. Secondary frequency is predicted by three kinds of boundary conditions characteristic.

• Journal of Biosystems Engineering
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• v.26 no.6
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• pp.579-588
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• 2001

• Archives of design research
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• v.17 no.2
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• pp.231-240
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• 2004

The present study approached conceptually the various problems which occurred in the living conditions during the modernization under the rapid growth drive and their solutions. It seems that the basis of the various problems which occurred in the highly informational and aged society lies in the discord of usability in the living conditions including the tools. It can be said that the secured social equity through the usability plays and important role in enhancing the quality of life of the prosumer, especially the elderly, by providing the self-confidence and the pleasure, and helping the smooth formation of the community The purpose of the present study was to find out the role of the design, as a professional field, on the various social pathological situation and the problems of the living conditions, and, especially, the role of the Universal Design on the desirable reorganization of the living conditions(the change of the living conditions through the community activation) which put the importance on the tool condition.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.83-105
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• 2007

The present study investigated counseling services and work conditions perceived by counselors in Healthy Family Support Centers. Questionnaire survey by mail was used to collect data from 32 counselors in Healthy Family Support Centers. Major findings of this study were as follows. First, many counselors in Healthy Family Support Centers perceived work load of counseling services heavily though they thought counseling work attractive and they would keep on working. Second, many counselors had a positive view of work conditions as a workplace but not a few of them complained about physical work conditions including poor facilities like lack of counseling room space in Centers. In addition to this, many suggestions were proposed to improve the counseling services and work conditions perceived by counselors in Healthy Family Support Centers.