• 연구논문집
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• s.22
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• pp.65-74
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• 1992

This paper aims at calculating optimum design dimensions to minimize the weight satisfied strain and stress intensity of the frame while loading maximum weight into a mechanical press in the static condition. Analysis of the frame was carried out by using the FEM, then the optimum condition was obtained by using these data. As modeling in the finite element analysis has great impact on the reliablity of analysis results, the analyzed object was selected a 150-ton mechanical press of J Company, the part little affected to structural rigidity was simplified, the load condition was considered in the only maximum load, the boundary condition was used by giving symmetric displacement due to symmetric boundary condition, the finite element was applied a linear membrane element. An intermediate processor program applied the normal ANSYS to analyze finite elements was developed, and the design sensitivity was calculated. This program was applied to the optimum design.

• Wind and Structures
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• v.1 no.1
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• pp.77-109
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• 1998

An evaluation and comparison of seven of the world's major building codes and standards is conducted in this study, with specific discussion of their estimations of the alongwind, acrosswind, and torsional response, where applicable, for a given building. The codes and standards highlighted by this study are those of the United States, Japan, Australia, the United Kingdom, Canada, China and Europe. In addition, the responses predicted by using the measured power spectra of the alongwind, acrosswind and torsional responses for several building shapes tested in a wind tunnel are presented and a comparison between the response predicted by wind tunnel data and that estimated by some of the standards is conducted. This study serves not only as a comparison of the response estimates by international codes and standards, but also introduces a new set of wind tunnel data for validation of wind tunnel-based empirical expressions.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.94-100
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• 1999

In this paper, we are implemented the courseware targets to the integrated a digital system analysis, a design theory, and a hardware description language training and a logic analysis. This paper consists of two subjects. One is that the learning of a digital system analysis, that of a design theory, and the training of a hardware description language is simultaneously performed. The other is that the experiment of courseware. To learn the hardware description language, the explanation using sound or moving images, setting-up of a simulation or a synthesis program, and simulating are executed on a courseware. And also, we proposed an integrated systems for the hardware description language and a logic synthesis. Also, The reliablity of the tool was verified to be preyed an efficient operation of an implemented digital system courseware tool by korea computer research association.

• Journal of The Korean Association For Science Education
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• v.15 no.4
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• pp.394-403
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• 1995

The purpose of this study was to find out and analyze the science teacher's teaching methods. A total of 35 teaching methods were abstracted from the previous studies and the relating literatures. An instrument to measure the frequencies of using methods was developed and then tested to middle school science teachers. The Results of two factor analysis methods were compared. The results are as follows: The instruments's reliablity coefficient(Cronbach ${\alpha}$) was 0.7707. The teaching methods which middle school science teachers have used frequently were represented as the proposing of the learning objectives, the deductive teaching, the experimental activities by teacher's guide, the summarization after explanation, the reading text etc. Also, it was revealed that they have not use the diagnostic evaluation, the formative evaluation, the experimental activities by student's design, the instructional medium. By confirmatory factor analysis, the 1st factor included 13 teaching methods and 2nd and 3rd factor included 9 and 7 methods respectedly. The meaning of 1st factor was interpreted to stimulate student's learning motives. And the other's were about the development of instruction. In exploratory factor analysis factors were overlapped or more fined. These were due to the structure of factors.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.12
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• pp.69-76
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• 1998

This paper proposes a matrix which represents the confidence in the rotation components of the Iterative Closest Point (ICP) algorithm is image registratiion, The reliability of the ICP algorithm depends on the shape of the object. For example, an object with more complex features shows higher reliablility than the one with rotation symmetry such as a cylinder. We show that the reliablity of the ICP algorithm can be estimated when the input range data has additive noise. Finally, we demonstrate that the proposed reliability formula is in good agreement with the computer simulation.

• The Journal of Korean Association of Computer Education
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• v.4 no.2
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• pp.115-123
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• 2001

In the early stage of Web-based Instruction, it didn't gain preference in spite of it's benefit of convenience. The main reason is, I think, the lack of generality at the education system which eventually results in unsatisfactory facilities compared with the requirement of teachers and students. And the early systems don't make good use of the plenty data in distributed environment, and don't show so good reliablity due to lack of systematic design and development. In this paper, we suggest WBI developing technology using the concept of WBSE. WBI developing is consist of component of pre-developed education software, integration of component using its reusability, and production of more requirement-satisfactory education software.

• Journal of The Korean Association For Science Education
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• v.13 no.1
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• pp.80-91
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• 1993

The purpose of this study is to develop an reliable instrument for evaluating science inquiry skills through an R&D procedure. A total of ten seience inquiry skills were selected for the development of the instrument, ie, observation, classifying, recognizing problems, measuring, inferring, formulating hypothesis, controlling variables, experimenting, interpreting and drowing a conclusion. And three items were developed for each sceince inquiry skill, totaling up to thirty items. The content areas of developed items are divided into three categories, material and energy, life and environment, and the earth and the space. There are 10 items for each category. The content validity and the objectivity of developed items were checked, verified in the two field trials and revised according to the analysis of items by seven experienced specialists with the degree of doctors in science education and five teachers who were studying for their master's degree in science education. According to the results of the second field trial. the content validity of the instrument was 91.1%, reliablity(K-R 20) 0.78, defficulty index 49.13%, discrimination index 0.42, mean achivement 61.85%, standard deviation 5.11, and standard error 2.40. Considering the above results, the developed instrument in this study is regarded as a appropriate instrument for evaluating science inquiry skills of elementary school students.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.251-260
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• 2009

Objectives : To investigate reliability and validity of Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index. Methods : The reliablity, construct validity of the Korean WOMAC Index in the patient of knee osteoarthritis was investigated. Test-retest reliability was quantified with pearson's correlation coefficient and intraclass correlation coefficient. Internal consistency was quantified with Cronbach's ${\alpha}$. and construct validity with pearson's correlation coefficient by correlating of the Visual Analog Scale(VAS). Results : Test-retest reliability of Korean WOMAC Index for pain was 0.76 to 0.95, stiffness was 0.89 to 0.94, and physical function was 0.71 to 0.95. Intraclass correlation coefficient for pain was 0.76 to 0.94, stiffness was 0.54 to 0.89, and physical function was 0.70 to 0.95. Internal consistency were 0.94 and 0.94 for the first and second time, respectively. Construct validity for pain was 0.79, for stiffness was 0.66, and physical function was 0.67. Conclusions : The Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index is reliable, valid assessment tool in knee osteoarthritis.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.5
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• pp.431-437
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• 2015

Recently, a miniaturized measurement cell of effective thermal conductivity was developed to evaulate the heat transfer characteristics of hydrogen stroage material in the initial step of its development. In this work, the realiablity issues which can occur from this miniaturization of measurement cell were studied in detail by both experiments and numerical simulation of heat transfer. $LaNi_5$ as a reference was used for the reliability evaluation of the miniaturized measurement cell. Numerical simulations of heat transfer for this measurement system were verified through comparison with the experimental data. Under these reliablity studies, we discuss how to overcome the inherent drawbacks of this miniaturized system in order to achieve the high reliability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.96-99
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• 2005

As the demand of internet networks using backbone communication systems recently increased, the researches on the high-speed wideband optical communication systems are required. For high-speed optical communication systems, asymmetric sampled grating distributed feedback laser diodes (DFB-LDs) are developed and the reliability of DFB-LDs is examined. The reliability of DFB-LDs is performed by monitoring I-V and L-I characteristics and two degradation phenomena related to the electrical characteristics of LDs are observed during the life tests. The first degradation phenomenon by increasing the reverse current is considered as a formation of leakage current path enough to prevent lasing operation in lateral blocking layer near active region of lasers. The second degradation phenomenon by decreasing the forward current is considered as activation of non-radiative Auger recombination process by thermal energy and the second degradation phenomenon is recovered after the off-test period at room temperature Eventually, evaluating the reliability of DFB LDs can allow us to improved the manufacturability in high-volume manufacturing.