• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.212-234
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• 1999

Dental restorative materials must have the physical properties to withstand wear and corrosion. Base metal alloys possess better mechanical properties and lower price than the gold alloys. For these reasons such alloys have largely replaced the precious metal alloys. One aspect to con-sider is the release of metal substances to oral environment. The release of elements from dental alloys is a continuing concern because the elements may have the potentially harmful biological effects on local tissues. The purpose of this study was to minimize metal release on the nonprecious metal surfaces by ion beam assisted deposition(IBAD) of titanium nitride (TiN) Ni-Cr-Be alloys with and without TiN coatings were secured in an wear test machine opposing ruby ball to determine their relative resistance to wear with loom, 200m, 300m and 400m sliding distance. And the corrosion behavior of the Ni-Cr-Be alloys with and without TiN coatings and 3 dental noble alloys have been studied. Potentiodynamic curves were used to analyse the corrosion characteristics of the alloys. The measurement of the released Ni and Cr ions was conducted by analysis of the electrolyte solution with atomic absorption spectroscopy. The results were as follows : 1. The critical sliding distance that wore down TiN coatings of $2.5{\mu}m$ thickness in this study condition was 300m. 2. Ion beam assisted deposition of TiN showed a good surface modification with respect to the properties of wear and corrosion resistance. 3. X-ray diffraction showed that the strongest peak of TiN is TiN(111) in the coatings. 4. The release of Ni and Cr ions from alloys measured by means of atomic absorption spectroscopy was reduced by ion beam assisted deposition of TiN.

• Particle and aerosol research
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• v.13 no.2
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• pp.79-85
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• 2017

This study identified the loss of minimum fluidization velocity and pressure in accordance with the superficial velocity of $NiO/MoO_3/MoS_2$, a rare metallic oxide and high value-added material in the lab-scale fluidized bed reactor (L=0.25 m, D=0.05 m). The average pressure loss in L/D 1, 2, and 3 of $NiO/MoO_3/MoS_2$ within the scope of superficial gas velocity between 0.07 and 0.45 m/s based on the L/D 1, 2, and 3 of the specimen was shown to be 290~1952 Pa at decreasing flux and 253~1925 Pa at increasing flux. The comparison between the theoretical value proposed by Wen and the test data showed a difference between 0.021~0.36 magnification. Based on these results, this study was able to determine the operation conditions where rare metallic oxides could be applied in real phenomena.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.143-158
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• 2015

The purpose of this research is to examine how emotional intelligence has a moderating effect on the relationship between emotional dissonance and job burnout and to investigate a mediating relationship between emotional dissonance and turnover intention through job burnout. To test the hypotheses, moderation analysis, mediation analysis and moderated mediation analysis were performed. Of the 300 self-report questionnaires distributed to hotel employees, 233 usable responses were received and utilized in the final analyses. The results show that emotional dissonance significantly affected job burnout, and job burnout completely mediated the effect of emotional dissonance on turnover intention. Additionally, emotional intelligence moderated the relationship between emotional dissonance and job burnout, suggesting that the emotional dissonance-job burnout relationship was stronger in the low emotional intelligence group than in the high emotional intelligence group. Particularly, emotional intelligence moderated the mediating relationship between emotional dissonance and life style intention via job burnout(moderated mediation effect), indicating that the mediation effect was stronger in the low emotional intelligence group. Therefore, hotel managers should efficiently implement strategies and programs to reduce emotional dissonance and job burnout and enhance emotional intelligence, which lead to lower turnover intention.

• Child Health Nursing Research
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• v.21 no.1
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• pp.55-63
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• 2015

Purpose: The purpose of this study was to identify cell phone addiction in school-age children and factors influencing addiction. Methods: The participants were 163 parents of elementary school students in the 1st to 4th grades. Data were collected through self-report questionnaires completed by the parents, and analyzed using the SPSS/WIN 19.0 IBM program. Results: Of the children, 86.5% were reported as being average users, 9.2%, at risk users, and 4.3%, at high risk users. Cell phone addiction in the children was significantly different according to games played by the children and parents' monthly income. Significant factors influencing cell phone addiction in the children were children's self-control, games played by the children, parents' cell phone addiction and parental control for children's cell phone use, explaining 24% of variance in cell phone addiction. Conclusion: The findings indicate that cell phone addiction in school-age children is influenced by parent-related factors as well as personal factors. Therefore approaches to education programs on cell phone use in school-age children should include parent-related factors as well as personal factors of the children.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.228-234
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• 1984

A partial hydrolysis of soybean protein isolate was carried out by using pepsin and trypsin. The degree of hydrolysis was evaluated by chemical analysis, viscometric measurements and gel electrophoresis. The functional properties of the hydrolyzates such as flow behavior, emulsion properties and foaming properties were evaluated. A selective hydrolysis of 11S protein fraction by pepsin was observed from the SDS-PAG electrophoresis. The changes in the molecular weight distribution by different conditions of enzyme hydrolysis were evaluated. The changes in the intrinsic viscosity of the protein hydrolylate by reaction time were highly correlated to the contents of TCA soluble protein and 0.03 M $CaCl_2$ soluble nitrogen. The degree of hydrolysis ($DH_{TCA}$, $DH_{Ca}$) were used to evaluate the effect of enzyme treatment on the functional properties of the hydrolyzate. The apparent viscosity and emulsion capacity and stability of the protein solution decreased as DH increased, while the foaming capacity increased linearly with the increasing DH.

• Journal of muscle and joint health
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• v.4 no.1
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• pp.48-60
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• 1997

This study was undertaken to identify the musculotendinous problems and contributing factors to those problems In students majoring in musical instruments in Korea. The data were collected from March 2, 1996 to March 31, 1996 from 261 music students in various geographical areas. The data were analyzed for descriptive statistics, t-test, chi-square using SPSS $PC^+$ program. The results of this study were as follows : 1. In a questionnaire survey of 261 music students, one hundred twenty five(47.9%) reported having had various musculotendinous symptoms. Twenty seven students among the those who had previous symptoms(21.9%) reported the present symptoms. 2. The experience rates of musculotendinous problems in keyboard players, string players and woodwind players were 50.3%, 48.2%, 33.3% respectively. 3. Most of the students practiced most intensively during their high school years and the musculotendinous symptoms began at the same period. 4. Pain, tenderness and stiffness were the most common symptoms, while paresthesia and motor dysfunction were rare. This indicates that most players had muscle tendinous overuse, while small number had nerve entrapment and motor dysfunction. 5. In past and present symptoms, string players experienced musculotendinous symptoms mainly in both sides of shoulders, lumbar area, left finger, and left wrist, while keyboard players experienced more symptoms in the right wrist, shoulder, fingers than left side. 6. The major contributing factors to the symptoms were weight of instrument, types of instruments, types of daily activities, duration of practice, and playing technique. 7 The most frequent treatment modalities for the symptoms were acupuncture or moxibustion, other alternative therapy such as heat compress and massage. Through this study it was found that the musculotendinous problems might be increased along with their career, due to lack of knowledge about preventive measures and patterns of health behavior seeking alternative modalities rather than professional consultation. Therefore, preventive measures that focus on playing habits such as duration of practice, frequency of rest and position while playing should be developed and taught to the students, their parents, and music educators. Doctors who are interested in this area should attempt to correct the position and posture while playing of the posture. And measures for reduction of loading of instrument weight should also be developed.

• Journal of Hydrogen and New Energy
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• v.24 no.1
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• pp.44-49
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• 2013

Hydrogen penetration into a metal leads to damages and mechanical degradations and its content measurement is of importance. For a precise measurement, a sample preparation procedure must be optimized through a series of studies on sample washing and drying. In this study, two-step washing with organic solvents and thermal soaking in inert gas were tried with a rod-shaped, API X65 steel sample. The samples were machined from a steel plate and then washed in acetone and etyl-alcohol for 5 minute each and dried with compressed air. After then, the samples were thermally soaked in a home-made nitrogen gas chamber during 10 minute at different heat gun temperatures from 100 to $400^{\circ}C$ and corresponding temperature range in the soaking chamber was from 77 to $266^{\circ}C$ according to the temperature calibration. Hydrogen residue in the samples was measured with a hot extraction system after each soaking step; hydrogen residue of $0.70{\pm}0.12$ wppm after the thermal soaking at $77^{\circ}C$ decayed with increase of the soaking temperature. By adopting the heat transfer model, decay behavior of the hydrogen residue was fitted into an exponential decay function of the soaking temperature. Saturated value or lower bound of the hydrogen residue was 0.36 wppm and chamber temperature required to lower the hydrogen residue about 95% of the lower bound was $360^{\circ}C$. Furthermore, a thermal desorption spectroscopy was done for the fully soaked samples at $360^{\circ}C$. Weak hydrogen peak was observed for whole temperature range and it means that hydrogen-related contaminants of the sample surface are steadily removed by heating. In addition, a broad peak found around $400^{\circ}C$ means that parts of the hydrogen residue are irreversibly trapped in the steel microstructure.

• Research in Community and Public Health Nursing
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• v.12 no.3
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• pp.732-745
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• 2001

This study attempted to identify obese students' stress and coping method in middle and high schools. The data were collected from the total of 600 obese students from middle and high schools in Pusan. The author used a convenience sampling method. The data collection was done from March 2 to April 30. 2001. The analysis of the data was done with SPSS Win(10.0) for descriptive statistics. t-test. and ANOVA. The instrument used for the obese students' stress and coping method was a questionnaire developed by Kim. Yi-Soon and Kim. Young-Hae(200l). The tool was composed of 65 items (33stress items: 32coping method items) with the five-point Likert scale. The results were as follow: 1. The average score of stress was 2.49 (SD = .86) points in the male students. and 2.83(SD= .86) points in the female students. The subcategories were: (outward appearance), (boyfriend/girlfriend), (occurrence of an outbreak of a disease), (relationship within the family), (an obese appearance), (difficulty in exercise). The highest degree of stress came from 'an obese appearance' for the male students (mean=2.64. SD=0.87) and (mean=2.64. SD=0.87) for the female students. 2. The subcategories of the coping method were: (be concerned about other matters), (recreation activities), (self-violence), (relaxation), (hobby activities), (avoid a situation), (communication), (music), (negative behavior), (positive thinking). The highest degree of coping method were (recreation activities) in the male students (mean=3.07. SD=0.86) and (music) in the female students (mean=3.47. SD=1.01). 3. The results comparing stress with demographic variables were significant for gender (t=7.010. p=0.000). grades at school (F=2.918. p=0.02l), degree of obesity (F=5.205. p=0.006). grades (F=2.550. p=0.027). standard of living(F=8.277. p=0.000). the state of health (F=2.882, p=0.022), relationship with the father (F=4.790, p=0.001), relationship with the mother (F=6.080, p=0.000), and the educational level of the father (F=3.192, p=0.013). 4. The results comparing the coping method with demographic variables were significant for gender (t=4.597. p=0.000). These findings contribute to the understanding of the degree of stress and the type of coping methods of obese students in middle and high schools. Therefore, the result of this study aids in an effective nursing intervention to improve the mental health program for the obese.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.333-346
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• 2000

The purpose of this study was designed to test and develope the structural model that explains health promoting behaviors among college students in Korea. The hypothetical model was constructed on the Pender's Health promotion Model(l996) and the inclusion of some influential factors for life satisfaction. The conceptual framework was built around eight constructs. Exogenous variables included in the model were self-esteem, perceived health status, self-efficacy, internal locus of control, chance locus of control. powerful other locus of control. Endogenous variables were health promotion behaviors and life satisfaction. The results are as follows; 1. The overall fit of the hypothetical model to the data was moderate <$x^2$=4.18(df=11. p=0.041), GFI= 0.99, AGFI= 0.76, RMR= 0.019, CFI= 0.99, CN= 248.50> 2. Path and variable of the model were modified by considering both its theoretical implication and statistical significance of parameter estimates. Compared to the hypothetical model. the revised model has become parsimonious and had a better fit to the data expected in a chi-square value <$x^2$=8.43( df= 16, p=0.21), GFI= 0.99, AGFI= 0.92., RMR= 0.024, CFI= 0.99, CN= 312.01> 3. Some of the predictive factors. especially self efficacy. self esteem. powerful others locus of control. perceived health status revealed the direct effects on health promoting behaviors. Of these variables. self-efficacy was the most signigicant factor. These predictive variables of health promoting behaviors explained 59% of total variances in the model. 4. Health promoting behaviors, self-esteem. and perceived health status revealed direct effect on the life satisfaction. Self-efficacy was identified as an important variable that contributed indirectly to improve life satisfaction by enhancing health promoting behaviors. These predictive variables of life satisfaction explained 42% of total variances in the model. In conclusion. the derived model in this study is considered appropriate in explaining and predicting health promoting models and life satisfaction among college students in Korea and could effectively be used as a reference model for further studies by suggesting a direction in health promoting nursing practices.

• The Korean Journal of Elementary Counseling
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• v.4 no.1
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• pp.263-284
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• 2005

The purpose of this study was to examine the effect of game-centered empathy training on the prosocial behaviors of elementary schoolers in a bid to suggest how their prosocial behaviors could be boosted. The research questions were posed as below: 1. Does game-based empathy training improve the overall empathy of school children? 2. Does game-based empathy training have a better effect on the cognitive empathy of school children or their emotional empathy? 3. Does game-based empathy training enhance the prosocial behaviors of school children? The subjects in this study were 62 children in their fourth year of D elementary school in Eumseong-gun, north Chungcheong province. They were divided into an experimental group and a control group, and a survey was conducted before and after the experimental group under-went empathy training for about six weeks. The instrument used in this study was David(1980)'s Interpersonal Reactivity Index adopted by Park Sung-hee(1996) to suit school children. Another instrument was Park Sung-hee (1997)'s inventory to assess the prosocial behaviors of children. The collected data were analyzed by SPSS 10.0 for Windows program, and reliability analysis and t-test were employed. The findings of the study were as follows: First, as for the effects of the game-based empathy training on the overall empathy of the elementary school youngsters that included both emotional and cognitive empathy, both groups got lower scores in posttest than in pretest. The experiment produced unexpected results, as the experimental group got significantly lower scores. This fact indicated that the game-based empathy training was ineffective. Second, the game-centered empathy training didn't exercise any influences on their cognitive and emotional empathy. The experiment had a reverse impact on the cognitive and emotional empathy of the experimental group, which implied that the training served as a factor to deteriorate the two types of empathy, and the hypothesis posed in this study was rejected. Therefore, which type of empathy could make a better progress by being exposed to the training couldn't definitely be determined. Third, the game-based empathy training didn't serve to Improve the prosocial behaviors of the elementary schoolers. There was no change in the experimental group, and this fact signified that there's something wrong with the attempt to develop school children's empathy to step up their prosocial behaviors. Based on the above-mentioned findings, the following conclusion was reached: First, the game-centered empathy training had no effects on boosting the overall empathy of the school children. Second, the game-centered empathy training couldn't be said to be effective in improving either cognitive empathy or emotional one. From a viewpoint of relativity, that could be said to affect emotional empathy more than cognitive one. Third, the game-based empathy training wasn't effective in improving prosocial behaviors. Rather, that resulted in interrupting the promotion of prosocial behaviors.