• Journal of The Korean Association For Science Education
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• v.33 no.3
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• pp.679-693
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• 2013

The purpose of this study is to develop an inventory to classify task commitment types of science learning and to classify highschool students' task commitment types. Firstly, inventory questions were designed following the literature analysis on the task commitment components which involve self confidence, high goal setting, and focused attention. Prototype inventory underwent the content validity test, pilot test, and reliability test. Through these steps, final inventory was input to 462 high school students and underwent the factor analysis and cluster analysis. Factor analysis confirmed three components of task commitment as the three factors of inventory questions. In order to find how many clusters exist, factors of developed inventory became new variables. Each factor's factor mean was calculated and served as the new variable of the cluster analysis. Cluster analysis extracted five clusters as task commitment types. The 5 clusters were suggested by the agglomarative schedule and dendrogram gained from a hierarchical cluster analysis with the setting of the Ward algorithm and Squared Euclidean distance. Based on the factor mean score, traits of each cluster could be drawn out. Inventory developed by this study is expected to be used to identify student commitment types and assess the effectiveness of task commitment enhancement programs.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.21-21
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• 2003

To increase the light-emission efficiency of LED, we increased the internal and external quantum efficiency by suppressing the defect formation in the quantum well and by increasing the light extraction efficiency in LED, respectively. First, the internal quantum efficiency was improved by investigating the effect of a low temperature (LT) grown p-GaN layer on the In$\sub$0.25/GaN/GaN MQW in green LED. The properties of p-GaN was optimized at a low growth temperature of 900oC. A green LED using the optimized LT p-type GaN clearly showed the elimination of blue-shift which is originated by the MQW damage due to the high temperature growth process. This result was attributed to the suppression of indium inter-diffusion in MQW layer as evidenced by XRD and HR-TEM analysis. Secondly, we improved the light-extraction efficiency of LED. In spite of high internal quantum efficiency of GaN-based LED, the external quantum efficiency is still low due to the total internal reflection of the light at the semiconductor-air interface. To improve the probability of escaping the photons outside from the LED structure, we fabricated nano-sized cavities on a p-GaN surface utilizing Pt self-assembled metal clusters as an etch mask. Electroluminescence measurement showed that the relative optical output power was increased up to 80% compared to that of LED without nano-sized cavities. I-V measurement also showed that the electrical performance was improved. The enhanced LED performance was attributed to the enhancement of light escaping probability and the decrease of resistance due to the increase in contact area.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.474-483
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• 2011

Solid-state fault current limiters (SSFCL) in power systems are alternative devices to limit prospective short circuit currents from reaching lower levels. Fault current limiters (FCL) can be classified into two categories: R-type (resistive) FCLs and L-type (inductive) FCLs. L-type FCL uses an inductor to limit fault level and is more efficient in suppressing voltage drop during a fault. In contrast, R-type FCL is constructed with a resistance and is more effective in consuming the acceleration energy of generators during a fault. Both functions enhance the transient stability of the power system. In the present paper, a novel SSFCL is proposed to enhance power system transient stability and power quality. The proposed SSFCL uses both functions of an L-type and R-type FCL. SSFCL consists of four diodes, one self-turn-off IGCT, a current-limiting by-pass inductor (L), and a variable resistance parallel with an inductor for improvement of power system stability and prevention of over-voltage across SSFCL. The main advantages of the proposed SSFCL are the simplicity of its structure and control, low steady-state impedance, fast response, and the existence of R-type and Ltype impedances during the fault, all of which improve power system stability and power quality. Simulations are accomplished in PSCAD/EMTDC.

• Korean Journal of Human Ecology
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• v.17 no.3
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• pp.469-483
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• 2008

Body image is important as it is related to self-esteem and can be enhanced by clothing and the degree of enhancement is related to clothing fit. The purpose of the paper is to find the adequate ease distribution of jacket pattern for the obese women who want to slenderize their shape by optical illusion. Subjective evaluation of the visual appearance we collected and, at the same time, 3D clothing air volume was observed for the nine types of experimental jackets with different ease distribution. As results it was found that jacket pattern for the obese women is that the front width of pattern is wider than what of back width in waist and abdomen. It was also noted that there was distance between clothing and skin in the girth around hip of jacket. 3D scanner clearly demonstrated the distribution of ease is useful to find the pattern variables responsible for the slender appearance of the obese women. The ready-to-made clothes for the obese women's clothing should be manufactured systematically in due consideration of the diversity and scarcity of the obese women's body shape.

• The Korean Journal of Health Service Management
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• v.10 no.2
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• pp.133-144
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• 2016

Objectives : This study sought to identify the predisposing factors which influence the adolescent oral health enhancement behavior by analyzing controlling effects depending on the parents' oral health care behaviors in the relationship between the predisposing factors and adolescent behavior improvements which enhance oral health. Methods : A structured, self-administered questionnaire was given from July 6 through July 24, 2016. The collected data were analyzed with the SPSS 18.0 program. Results : Parents' oral health behaviors in terms of discipline and guidance showed a controlling effect in terms of importance (${\beta}$=.116) and benefits (${\beta}$=.133). In addition, the analysis showed that the parents' oral health care behavior had a controlling effect in terms of benefits (${\beta}$=.164) and susceptibility (${\beta}$=-.116). Conclusions : From the results of this study, the development of materials and education courses to lead to behavior changes are thought to be necessary in order to enhance the importance and benefits of the factors of oral health beliefs and to reduce psychological discomfort. Moreover, the role of parents with regard to desirable habits and beliefs to maintain oral health in their children is essential.

• Korean Journal of Human Ecology
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• v.17 no.4
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• pp.623-630
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• 2008

An educational program through therapeutic recreation was developed in order to analyze the effect of enhancement of ego integrity of the elderly. First of all, this study was designed to summarize the concepts of ego integrity and the effects of therapeutic recreation on the elderly and to identify elderly's educational needs of both educational methods and contents from the literature review. The above identified knowledge and information were applied to developing the educational program. The program was composed of 6 sessions with 17 old men and women focused on developing self acceptance using reminiscence on ego integrity through their whole life span and developing positive and active attitudes towards life. And enforcing and evaluation methods were also suggested. The results were as follows. This program showed the significant differences between post-test and pre-test scores in the scale of ego integrity of the elderly. In conclusion, educational program through therapeutic recreation employed for this study has significant effects of increasing ego integrity of the elderly.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.589-598
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• 2003

In the conventional fractal image compression in the DWT(discrete wavelet transform), the domain and range blocks were classified as B${\times}$B block size first before all domain block for each range block was searched. The conventional method has a disadvantages that the encoding time takes too long, since the domain block for entire image was searched. As an enhancement to such inefficiencies and image quality, this paper proposes wavelet-based fractal image compression with multiscale factors. Thus, this proposed method uses multiscale factor along each level and band to enhance an overall image quality. In encoding process of this method, the range blocks are not searched for all the domain blocks; however, using the self affine system the range blocks are selected from the blocks in the upper level. The image qualify of the conventional method is 32.30[dB], and the proposed method is 35.97[dB]. The image quality is increased by 3.67[dB].

• Wind and Structures
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• v.7 no.4
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• pp.251-264
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• 2004

The effects of a class of nonlinear Tuned Mass Dampers on the aeroelastic behavior of SDOF systems are investigated. Unlike classical linear TMDs, nonlinear constitutive laws of the internal damping acting between the primary oscillator and the TMD are considered, while the elastic properties are keept linear. The perturbative Multiple Scale Method is applied to derive a set of bifurcation equations in the amplitude and phase and a parametric analysis is performed to describe the postcritical scenario of the system. Both cubic- and van der Pol-type dampings are considered and the dependence of the limit-cycle amplitudes on the system parameters is studied. These new results, compared with the previously obtained bifurcation scenario of a SDOF aeroelastic oscillator equipped with a linear TMD, show a detrimental effect on the maximum limit-cycle amplitude reduction of the nonlinear TMD. However, the analyses evidence that in the parameter region away from the perfect tuning condition the nonlinear connection can be used to tune the system with an enhancement of the limit-cycle amplitude reduction.

• Korean Journal of Human Ecology
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• v.12 no.5
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• pp.605-618
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• 2003

The purpose of this study was to develop the household analysis and diagnosis program for the enhancement of family welfare focusing on the household of middle-aged full-time housewives. From the review of related literatures, the following areas of total family life were selected ; household management, time use, housing, household materials, finance, communication and decision making. Considering that the program subjects were middle-aged full-time housewives, the preparation for elderly life and the identity as housewife, one of the healthy family members, are appended. The progresses for the development of household analysis and diagnosis program were as follows: 1. to select the useful area of family life, 2. to make the indicators which explain the status of family life, and 3. to decide the scales for the diagnosis. This program has various uses such as the development of self-evaluation program, program for various family life course. Through this program the strength and weakness of family life can be found and the planning for the enforcement of family life can be practiced.

• The Journal of the Korea Contents Association
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• v.7 no.8
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• pp.191-198
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• 2007

Due to the growth of female movement after 1970s' and the resultant interest in female activity changed the type and degree of female crime and thus led to considerable interest and research. As a result, the relative difference between crime rates of sexes has been reduced, but the crime of male and female has been considerably decreased owing to sex role and concept of self-ego, more generally specking, the result of female movement. As countermeasure for the recently increasing frmale crime, this research presents first, enhancement of social education; second, arrangement of relevant institutions; third, activation of the system of female investigator; fourth, the necessity of victimology approach.