• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.190-193
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• 2005

The purpose of the present study is to design a 500W-class micro scale composite wind turbine blade. The blade airfoil of FFA-W3-211 was selected to meet Korean weather condition. The skin-spar-f Dam sandwich type structure was adopted for improving buckling and vibration damping characteristics. The design loads were determined at wind speed of 25m/s. and the structural analysis was performed to confirm safety and stability from strength. buckling and natural frequency using the finite element code. NISA II [6]. The prototype was manufactured using the hand-lay up method and it was experimently tested using the sand bag loading method. In order to evaluate the design results. it was compared with experimental results. According to comparison results. the estimated results such as compressible stress. max tip deflection natural frequency and buckling load factor were well agreed with the experimental results.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.3
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• pp.77-83
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• 1985

This paper considers the problem of stabilizing a class of continuous-time large scale linear systems when the system parameters are uncertain. The proposed local adaptive controls are a combination of a new adaptive feedback control and the conventional linear feedback control. A condition of stability is derived , under which the overall closed-loop system is assured to be globally stable. Also, a numerical example is illustrated via computer simulation.

• Journal of Korean Home Economics Education Association
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• v.10 no.1
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• pp.153-169
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• 1998

The purposes or this study were to develop the scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scales for the Home Economics Textiles class in high school. First, through review of literature concerned, scientific experimental model was defined, and the usefulness of this model on the teaching situation testified on other subjects such as Physics and Bilolgy, was reviewed. Secondly, scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scale were developer on the bases on APU evaluation model, experimental guidelines for teachers, experiment planning & report form for students, evaluation scale applicable to the teaching situation ere established by analysing the significant differences scientifically.

• Journal of the Korean Statistical Society
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• v.19 no.1
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• pp.24-44
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• 1990

The purpose of this paper is to extend the idea of Tamhane and Bechhofer (1977, 1979) concerning the normal means problem to some general class of distributions. The key idea in Tamhane and Bechhofer is the derivation of the computable lower bounds on the probability of a correct selection. To derive such lower bounds, they used the specific covariance structure of a multivariate normal distribution. It is shown that such lower bounds can be obtained for a class of stochastically increasing distributions under certain conditions, which is sufficiently general so as to include the normal means problem as a special application. As an application of the general theory to the scale parameters problem, a two-stage elimination type procedure for selecting the population associated with the smallest variance from among several normal populations is proposed. The design constants are tabulated and the relative efficiencies are computed.

• Journal of the Korean Institute of Educational Facilities
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• v.1 no.2
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• pp.33-46
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• 1994

This paper inquires into the most desirable measures which can diversify instruction-learning methodsand take advantage of educational facilities in order to carry out both education for the whole man and individualized instruction in a smallscale class primary school. For this purpose, this paper makes investigation into thirty primary schools at Pochon district(including one branch school) and analyzes the contents of investigation into as follows: 1) the general present status of primary schools at Pochon district educational facilities, 2) the educational environment and educational facilities, 3) the instructional systems design and instructional media, 4) the educational facilities for the scale of applying instructional media. And then, on the side of educational facilities, This paper makes proposal for eight accessible alternatives which diversify instruction learning methods and enforce individualized instruction (=open education) without expanding or reconstructing on alarge scale a building of the existing small-scaleprimary schools.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.3
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• pp.89-96
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• 1985

This paper presents a decentralized adaptive scheme to stabilize a class of large-scale discrete-time linear systems subject to system parameter uncertainties. The scheme combines an adaptive nonlinear feedback control for compensating some effects by unknown system parameters and the exact model-based linear feedback control for overriding the unfavorable effects by interconnections. A condition of stability is derived, under which the overall adaptive system is assured to be globally stable. Also, a numerical example is provided to illustrate the feasibility of the scheme.

• Progress in Superconductivity and Cryogenics
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• v.15 no.3
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• pp.29-34
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• 2013

This paper introduces design processes of 10 MW class superconducting generator for wind Turbine. Superconducting generator can produce 5 times stronger magnetic field than permanent magnet at least, which enables large scale wind turbine to function as a lighter, smaller and more highly efficient system. These processes are targeted for higher efficiency and shorter high temperature superconductor (HTS) wires to fabricate 10 MW class superconducting generator. Three different approaches will be described in these design processes. First design process focuses on the number of rotor poles. Secondly, 270 and 360 A operating current of superconducting field coil can be adapted as a design parameter in this process. Lastly, 3 and 6 kV line to line voltage of stator coil will be used to design 10 MW class superconducting generator.

• Journal of Information Technology Services
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• v.12 no.4
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• pp.307-318
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• 2013

This study developed the prevention education program of smartphone overuse for adolescents in middle school and testified its outcome. Finally the 4-session prevention education program for smartphone overuse was developed. 1st session was composed of psychoeducation about smartphone overuse and its side effect by quiz question. 2nd session smartphone addiction and brain change, 3rd session motivational enhancement program for smartphone overuse, 4th session cognitive behavioral program for it. The outcome was testified by internet addiction scale, smartphone addiction scale, and school adaptation scale for 2 classes of middle school students(experimental and control class). 2 Main results were as follows; First, the smartphone addiction total score and cyberworld orientation of the students participating in it were statistically significantly reduced. The difficulty of daily living and abstinence symptom due to smartphone overuse of them tended to reduce. Second, internet addiction total and all subscores of them were not changed. Third, class adaptation of them was statistically significantly increased and school adaptation total score and teacher adaptation of them tended to increase. Its meaning, implication and limitation were discussed.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.11-24
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• 1976

This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.286-298
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• 2006

Purpose: This study was to develop an online 'alternative therapy and health promotion' class for university students and to evaluate its changes. Method: The online class was developed based on the Instructional Systems Development(ISD) model and model of Web-Based Instruction(WBI) developmental process. This was a quasi-experimental, one group pretest-posttest design. The subjects of this study were 130 students in 3 universities, and they were provided the cyber class for 16 weeks. Data was analyzed by descriptive and plural answer statistics, and paired t-test. Results: The cyber class was developed in five steps : analysis, design, data collection and reconstruction, programing and publishing, and evaluation. The results of program evaluation were positive, which included learning 3.47. system 3.57, and learning satisfaction 3.64 on the scale of 5. The posttest scores of cognition and reliability of alternative therapy were higher than pretest scores. The posttest score of health promoting lifestyle(t=-5.051, p=.000) and perceived health status(t=2.979, p=.003) were significantly higher than those of the pretest. Conclusion: These results suggest that the cyber class is a positive method in increasing a cognition, reliability of alternative therapy, and is effective to improve a health promotion lifestyle and perceived health status for the university students.