• Transactions of Materials Processing
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• v.13 no.8
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• pp.731-737
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• 2004

Mechanical properties such as Young's modulus and hardness of thin film in coated steel are difficult to determine by nano-indentation from the conventional analysis using the load-displacement curve. Therefore, an analysis of the nano-indentation loading-unloading curve was used to determine the Young's modulus, hardness. A new method is recently being developed for elastic-plastic properties of materials from nano-indentation. Elastic modulus of the thin films shows relatively small influence whereas yield strength is found to have significant effect on measured data. The load-displacement curves of material tested with a Berkovich indenter and nano-indentation continuous stiffness method is used to measure the modulus and hardness through thin films, and then these are computed using the analysis procedure. The developed neural networks apply also to obtain reliable mechanical properties.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.410-414
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• 2004

Under longitudinal loading continuous fiber reinforced metal matrix composite(MMC) have interpreted an outstanding performance. However, the applicability of continuous fiber reinforced MMCs is somewhat limited due to their relatively poor transverse properties. Therefore, the transverse properties of MMCs are significantly influenced by the properties of the fiber/matrix interface. In this study, elastic-plastic behavior of transversely loaded unidirectional fiber reinforced metal matrix composites investigated by using elastic-plastic finite element analysis. Different fiber placement(square and hexagon) and fiber volume fractions were studied numerically. The interface was treated as three thin layer (with different properties) with a finite thickness between the fiber and the matrix. The analyses were based on a two-dimensional generalized plane strain model of a cross-section of an unidirectional composite by the ANSYS finite element analysis code.

• Journal of the Korean Institute of Educational Facilities
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• v.20 no.6
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• pp.31-40
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• 2013

The purpose of this study is to understand the meaning of architectural history of designated cultural properties of modern educational facilities through the analysis of its status. This study considerate acceptance and evolution of modern educational facilities during the about seventy years from 1895 to 1965. Also, this study analyzes items that is distribution of construction and designation year, regional groups, and status of main structure material, status of conservation and utilization of facilities, its characteristics of architectural style. In this study, the result of analysis show that most analysis items of investment buildings are tend to biased and concentration to one direction. Accordingly, designated cultural properties of modern educational facilities are weakly express architectural representation and symbolism in the period of modern educational acceptance.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.111-118
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• 1997

Granulation procedure was carried out in a 0.109m I. D., 1.8m height fluidized bed coal combustor of the multi-sized particles. The domestic anthracite with heating value 3240kcal/kg was used. Granulation of fine coal particles and fluidizing characteristics were investigated by the pressure fluctuation properties such as mean pressure, standard deviation of pressure fluctuation and power spectrum distribution. Defluidization state and granulation mechanism were also studied by the various analysis. It was found that the conversion efficiency in the elutriated stream was increased by the coalescence of fine coal particles. Defluidization and pressure fluctuation properties were interrelated and this result was indication of the capabilities of pressure fluctuation properties analysis in the diagnostics of fluidizing state.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.103-108
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• 2013

This paper describes basic properties tests and non-rotating dynamic test for rotor blade, flexbeam, and torque tube of which bearingless rotor in helicopter consists. A basic properties test are bending and twist test to find the flap stiffness, lag stiffness, and twist stiffness of specimens. The purpose of dynamic test is to find natural frequencies and modes in non-rotating state. The test results are used to update the analysis model. The updated analysis results using rotorcraft comprehensive code match the tests quite well. The updated model input based on the tests will be utilized to analysis the conditions of rotating whirl tower test before the whirl test and will be compared with the whirl tower test results.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.1
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• pp.8-17
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• 2019

Perforated plates are used for the steam generator tube-sheet and the Reactor Vessel Closure Head in the Nuclear Power Plant. The ASME code, Section III Appendix A-8000, addresses the analysis of perforated plates, however, this analysis is only limited to the flat plate with a triangular perforation pattern. Based on the concept of the effective elastic constants, simulation of flat and spherical perforated plates and their equivalent solid plates were carried out using Finite Element Analysis (FEA). The isotropic material properties of the perforated plate were replaced with anisotropic material properties of the equivalent solid plate and subjected to the same loading conditions. The generated curves of effective elastic constants vs ligament efficiency for the flat perforated plate were in agreement with the design curve provided by ASME code. With this result, a plate with spherical curvature having perforations can be conveniently analyzed with equivalent elastic modulus and equivalent Poisson's ratio.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.87-98
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• 2020

This study analyzed milk consumption behavior of college students. According to the results of the analysis, the respondents mainly purchase milk with a capacity of 900 to 1,000 ml at the hypermarket. However, it was found that convenience stores mainly purchase 200 ml capacity. According to the results of factor analysis on milk purchase factors, milk purchase factors were classified into nutritional and cosmetic attributes. Nutritional properties include nutritional ingredients, sterilization method, bio-origin, quality, HACCP labeling, milk fat ratio, etc., and external properties include brand, manufacturer, packaging/package design, and manufacturing date. In order to expand the milk consumption of the young generation, I think it is necessary to strengthen marketing strategies.

• Transactions of Materials Processing
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• v.31 no.2
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• pp.81-88
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• 2022

Numerical analysis and dynamic material properties are required to analyze the behavior of workpiece during an electrohydraulic forming (EHF) process. In this study, EHF experiments were conducted under three conditions (6, 7, 8 kV). Dynamic material properties of Al 5052-H34 were inversely estimated through an ANN (Artificial Neural Network) model constructed based on LS-Dyna analysis results. Parameters of Cowper-Symonds constitutive equation, C and p, were used to implement dynamic material properties. By comparing experimental results of three conditions with ANN model results, optimized parameters were obtained. To determine the reliability of the derived parameters, experimental results, LS-Dyna analysis results, and ANN results of three conditions were compared using MSE and SMAPE. Valid parameters were obtained because values of indicators were within confidence intervals.

• Korean Journal of Community Nutrition
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• v.15 no.1
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• pp.83-93
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• 2010

The purpose of this study is to investigate consumer perception and importance of food tourism properties and performance of the properties in Sangju province of Gyeongsangbuk-do. The study has found that persons who have food tourism experiences (75 persons, 50.7%) had slightly more than not experience persons (72 persons, 48.6%). Additionally, most of the respondents were usually satisfied with the local foods. Also, it was found that food tourism had been taken 1-2 times per 6 months (48 persons, 64.0%) on average, and 135 persons (91.2%) had intention of experiencing food tourism. According to the result of Importance-Performance Analysis (IPA) on consumers' food tourism properties, high importance was on 'There are attractive landscapes.' ($4.52\;{\pm}\;0.56$), 'Accommodations with reasonable price.' ($4.18\;{\pm}\;0.80$), and 'The food of the area is famous.' ($4.15\;{\pm}\;0.73$); and the properties such as 'There are local specialty shops or markets selling local produce.' ($3.03\;{\pm}\;0.83$), 'The climate is temperate.' ($3.03\;{\pm}\;0.87$), and 'There are attractive landscapes.' ($3.02\;{\pm}\;0.98$) showed average performance. A factor analysis about consumers' importances to the food tourism properties shows that the factors were divided into four kinds and each of the factors were named as 'convenience-stable propensity', 'valued-oriented propensity', 'adventurous-aggressive propensity' and 'traditional-active propensity'. Variance ratios of each factor were 22.319%, 10.286%, 8.723% and 6.239%, respectively. According to the result of a reliability analysis, Cronbach's alpha value was 0.8621, implying that reliability of each item was very high. Therefore, it is considered that development of food tourism products and promotion strategies therefore should be designed based on the importance of food tourism properties hereafter.

• Analytical Science and Technology
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• v.8 no.3
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• pp.341-350
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• 1995

$Nd_{14}Fe_{80}B_6$ ribbon alloy was manufactured with using melt-spinning method and analyzed the magnetic properties according to the manufacturing conditions. The microstructure and magnetic properties of melt-spun ribbons are sensitively dependent on the quench rate and annealing conditions. As-quenched $Nd_{14}Fe_{80}B_6$ ribbons with optimum magnetic properties are obtained at wheel speed($v_s$) of about 20m/sec and over quenched ribbons show optimum magnetic properties at $v_s$=22m/see when annealed for 30 minutes at $600^{\circ}C$ under vacuum. The crystallization temperature($T_k$) of $Nd_2Fe_{14}B$ phase is about $595^{\circ}C$ in the DTA analysis.