• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.5-12
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• 2008

Biot proposed the frequency dependent formulation for the propagation of elastic waves in saturated media based on the coupled theory mixtures. Based on Biot theory, a special frequency called 'the characteristic frequency' contains unique information of the permeability of soils. The characteristic frequency is measured from I/Q (inverse quality factor) versus frequency curve by an acoustic sweep test, and the permeability of soils is computed from Biot equation. In this paper, laboratory tests are performed at The University of Mississippi using a large test box. The measured characteristic frequency is consistently obtained at 3500 Hz for mortar sands. The computed permeability of mortar sands based on Biot equation turned out 2.01 $10^{-4}m/sec$, while the permeability from the laboratory constant head test turned out 1.49 $10^{-4}m/sec$. This paper addresses the theoretical background and experimental procedure of this technique.

• Journal of the Korean Home Economics Association
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• v.40 no.8
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• pp.49-60
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• 2002

The purpose of this study was to analyze effects of child's age, language ability, social competence, parenting style, and socioeconomic status on preschoolers' theory of mind. The subjects were selected randomly from kindergartens and composed of three hundred 3-, 4-, and 5-year-olds and their parents and teachers. The data was analyzed by analysis of covariance and t-test. The major findings of this study were summarized as follows: it was found that language ability, parenting style, SES, and social competence had a positive effect upon preschoolers' theory of mind. This relation remained significant with children's age controlled. Children's theory of mind was more strongly related when their parents were highly affectionate with their children, children's language ability was greater, parents held higher socioeconomic status than those who had less prominent one, or children with higher social competence.

• Journal of The Korean Association For Science Education
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• v.12 no.3
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• pp.91-107
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• 1992

The Purpose of this study was to present the procedures and methods of ordering theory,and to search for a learning hierarchy among science process skills in each Piagetian cognitive reasoning level. One of the purpose of this is not to determine the clear and exact hierarchy but rather to demonstrate how ordering theoretic methods and procedures can be used to determine the hierarchy of logical relationships among a set of test items or the testing of a hypothesized hierarchy. Ordering theory was used to analyze five science process skills collected from 509 high school students. Ordering Theory has as its primary intent either the testing of hypothesized hierarchies among items at the determination of hierchies among items. Hierarchical relationships were identified within five science process skills. The results will be helpful in giving useful inform at ions to classroom teachers and science curriculum developer.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.2
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• pp.63-70
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• 2011

Despite the high historical and topological values, closed schools are rarely reutilized. The reason can be likely explained by integrity of the building structure and unawareness of the operation and maintenance for closed schools. The purpose of this study is finding a possibility of reusing closed schools by deploying SI (Skeleton and Infill) theory. SI theory is separating the "skeleton" like structure from "infill" such as interior furnishings to extend building life without complete demolishing of the building. It will allow satisfying various local community demands by alternating infill without demolishing of historical and topological value of the building. The experimental test was undertaken with closed school for this study. The local community's demands or opinions were reflected to develop a strategy for deploying infill system especially movable storage furniture to closed school. The study finds possibilities that SI theory can assist local community to 1) construct potential demand for utilizing closed school and 2) suggest strategy for operating and maintaining closed school.

• Journal of Power System Engineering
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• v.3 no.2
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• pp.89-97
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• 1999

In this paper the forming simulations of ellipse bulge have been researched by using $PAM-STAMP_{TM}$ to estimate the sheet metal forming and the plastic deformation characteristic of ellipse bulge. Thin elliptical diaphragms of brass, copper, aluminum, and mild steel are bulged in elliptical dies having aspect ratios of 1.33 and 2. In order to compare the simulation results with the experiment and ellipse bulge's theory derived by using Johnson and Duncan's theory, the relations of hydraulic pressure and polar height, polar thickness strain and polar height, were compared. According to this study, the results of simulation and ellipse bulge's theory derived by using Johnson and Duncan's theory, and the bursting pressure and the bursting polar height are good agreement to the experiment. So, the results of simulation by using $PAM-STAMP_{TM}$ and the ellipse bulge's theory will give engineers good information to make assessment the formability and plastic deformation characteristic of hydraulic ellipse bulge test.

• Transactions of Materials Processing
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• v.26 no.5
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• pp.293-299
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• 2017

In this paper, finite element stamping analysis was carried out for the front lower arm to examine the applicability of solid element with damage theory to predict shear fracture phenomena induced by sheared edge as well as deformation mechanisms. Mechanical properties related to deformation and damage theory were determined from tensile test. Shear fracture was predicted by normalized Cockcroft-Latham model with initial imposition of the damage value along the sheared edge. Simulation results illustrated that the analysis with solid element and damage theory predicted edge profile, strain distribution, and forming load more accurately than the analysis with shell element. Simulation with solid element can also predict the shear fracture more exactly comparing to analysis with shell element and forming limit curve.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.337-339
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• 2005

본 논문에서는 임베디드 시스템의 제어를 위해 동기화 언어인 에스테렐로 개발된 소프트웨어가 소프트웨어 요구사항을 만족하는지 확인하기 위한 Model-based Test(MBT) 프레임 워크를 제안한다. 제안된 프레임 워크를 기반으로 작성한 프로토 타입의 테스트 도구는 요구사항 모델을 창조하여 On-the-fly 방법을 통해 테스트 케이스를 랜덤하게 자동으로 생성하여 소프트웨어에 대하 테스트를 자동으로 수행한다. 간단한 case study로 레고 마인드스톰 로봇 제어 소프트웨어에 MBT를 수행하고 그 결과를 확인한다.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.1
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• pp.135-142
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• 1997

The objectives of this study was to test applicability of the theory of planned behavior by Ajzen & Driver(1992), to predicting summer vacation activity participation. Vacations to vist Sock-Cho City in summer were asked to complete a questionaire to measure attitudes, subjective norms, perceived behavioral control, and intentions in relation to participating in three vacation activities, at the beach, at the valley, and at the pool. After summer vacation, respondents were called to answer whether or not they had participated in those activities. The results showed that attitudes toward vocation consist of affective and instrumental component Consistent with the theory, attitudes, subjective norms and perceived behavioral control were significant variables in predicting intentions to participate in vacation activites. In addition, intentions and perceived control were influential in predicting vacation activities partication. Althouh the objectives of the study were achived, this application of the theory of planned behavior to Koreans summer vacation participations did not show the same power as the Ajzen & Driver's study(1992) in predicting recreation activties participation. It would be desirable for future research to apply the theory of planned behavior to various recreational settings.

• Journal of the HCI Society of Korea
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• v.6 no.1
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• pp.17-20
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• 2011

The contingency theory of leadership was proposed by F. Fiedler. In his theory, he divided the group into Task oriented and Relationship-oriented people based on work-style by LPC(Least Preffered Co-workers) test. This survey searches significance of interaction usage depending on which group has more aggressive interaction on the address list with mobile phones focusing on the differences between mainfunctions (name, cell phone, group name) and sub-functions (birthday, Photo, E-mail). Itis the hypothesis that the relationship-oriented group has more interaction than the task-oriented group which was identified through the analyzed usage of the address list. Results show that the contingency theory was not appropriately related with the research. Interaction usage by the following task based on Fiedler's contingency theory of leadership isn't related much. However, by discovering the interesting patterns by the test, this research is able to guide human-centered address design directions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.1
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• pp.41-48
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• 1992

Various soil behaviors usually occurring in the geotechnical problems, such as, cutting and embankments, stability of slope, seepage, consolidations, shearing failures and liquefaction, should be predicted and analyzed in any way. An approach of these predictions may be followed by the development of the constitutive equations as first and subsequently solved by numerical methods. The purpose of this paper is develop the constitutive equation of sands uder monotonic or cyclic loadings. The constitutive equation which is based on elasto-plastic theory, modified anisotropic consolidated stress parameter by Sekiguchi et al and Pender's theory is derived. And the equation is included a new stress parameter, hardening function, Bauschinger's effects and Pender's theory. The model is later evaluated and confirmed the validity by the test data of Ottawa sand, Banwol sand Hongseong sand. The following conclustions may be drawn: 1. The consititutive equation which is based on elasto-plastic theory, modified anisotropic consolidated stress parpameter by Sekiguchi et al and Pender's theory is derived. The equation in included a new stress parameter, hardening function, Bauschinger's effect and Pender's theory. 2. For Ottawa sand, the result of the constitutive equation shows a better agreement than that of Oka et al. The result of axial strain agrees well with the tested data. However, the result of horizontal strain is little bit off for the cyclic loadings or large stress. It is thought that the deviation may be improved by considering Poisson's ratio and precise measurement of shear modulus. 3. Banwol sand is used for the strain and stress tests with different relative densitites and confining pressures. The predeicted result shows a good agreement with the tested data because the required material parameters were directly measurd and determined form this laboratory. 4. For Hongseong sand, the tests under same amplitude of cyclic deviatoric stress shows a similar result with the tested data in absolute strain. It shows the acute shape of turning point because the sine wave of input is used in the test but the serrated wave in prediction.