• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.97-101
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• 2003

Mn-Zn ferrite microwave absorbers mixed with silicon for mobile phone were prepared and the effect of preparation temperature of specimens on absorption ability was studied. A sample with the thickness of 1 mm prepared at 70 $^{\circ}C$ showed excellent absorption ability of 3.4 ㏈ at 1.8 GHz which is a frequency band for mobile phone. A loss factor of tan $\delta$ > 1 is shifted toward lower frequency as increasing preparation temperature of specimens.

• Journal of Technologic Dentistry
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• v.26 no.1
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• pp.89-96
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• 2004

Hydroxyapatite powder were synthesized by precipitation method, varying pH, and reaction temperature. The powders were heated at 1,200$^{\circ}{\cdots}$ and 1,300$^{\circ}{\cdots}$ for fabrication of dental prosthesis. The results are as follows: Synthesized powder showed the smallest particle in size, under the conditions of pH 11 and reaction temperature 37$^{\circ}{\cdots}$. The hydroxyapatite was partially converted to $\alpha,\;\beta$-TCP at 1,200$^{\circ}{\cdots}$ and 1,300$^{\circ}{\cdots}$. Mechanical strength of sample was affected by such powder preparation conditions as pH and reaction temperature and sintering temperature. The mechanical strength of sample prepared under the same conditions was increased with increasing pH, reaction temperature and sintering temperature.

• Journal of Plant Biology
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• v.25 no.1
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• pp.21-36
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• 1982

The activity of photosystem II in isolated chloroplast form the leaves of Sedum sarmentosum was measured. The photoreduction rate of DCPIP by photosystem II showed the circadian rhythm with a peak at near midday sample for a continuing fine day and at near afternoon between nidday and sunset sample for a continuing cloudy day in summer. The optimum light intensity of photoreduction by photosystem II in the chloroplast preparation was about 5~9$\times$$10^4$ lux. The saturated light intensity was over 9$\times$$10^1$lux. Photosystem II activity was inhibited by even the lowest concentration of lead. When Pi and ATP of the same concentration as Pb were added to the reaction mixture containing Tris buffer lacking of Pi prior to Pb incubation, photosystem II activity was protected from Pb-inhibiting effect by the pretreament of Pi and ATP. It was assumed that Pb inhibiiton was probably due to one, P-depriving by the precipitates of $Pb_3$ $($Pb_4$)_2$ in the reaction mixture and the other, partially Pb-combing with Pi groups of the active site of photosystem II.

• YAKHAK HOEJI
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• v.21 no.2
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• pp.87-94
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• 1977

The rheological properties of some honey-ginseng powder mixturs, used as pharmaceutical pills, were studied extensively by employing five kinds of honey, acacia, chestnut, buckwheat, green perilla and bush clover. Relation between the viscosity of the sample mixtures and the concentrations of ginseng powder and the temperature effect on the internal change of the structure were studied. The results obtained are as follows: 1) A complete gel formation of honey-ginseng mixtures was observed when about 50 days have passed after the sample preparation. 2) The viscosity of honey-ginseng powder mixtures was related with the concentration of ginseng powder, the temperature and the period of time required in gel formation as shown in the following equation. n=noexp$[{\kappa}_{1}c^{n1}+{\kappa}_{2}(T-273)^{-n2}+{\kappa}_{3} t^{n3}]$

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.2
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• pp.177-192
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• 2018

The mission of the university is to grow young people who will be responsible for the next generation nation to mature society. In particular, the role of universities in the 4th Industrial Revolution era is to foster creative talents. Therefore, innovative changes are required for existing infusion education and employment-oriented college education contents and teaching methodology. In the high youth unemployment rate, entrepreneurship education is spreading to universities to innovate existing organizations and create new jobs. Until now, however, the effects of university entrepreneurship education have been studied mainly in the field of start-up. Therefore, it is very difficult to study various effects on entrepreneurship education. In this study, empirical analysis of the effect of entrepreneurship training on career preparation behaviors of university students who are about to enter the society is verified. The sample of this study was surveyed from August, 2016, and the questionnaire was applied to 393 university students who selected 5 universities and entrepreneurship education. As a result of the analysis, the ability of communicative communication and creative problem solving cultivated through entrepreneurship education had a positive effect on entrepreneurship and self - efficacy, Entrepreneurship and self - efficacy had a positive (+) positive effect on career preparation behavior. However, cooperative communication ability, creative problem solving ability, and effective work behavior ability by entrepreneurship education were not directly related to career preparation behavior. On the other hand, in verifying the mediating effect of entrepreneurship and self - efficacy, it proved that mediating role of positive communication between collaborative communication ability, creative problem solving ability and career preparation behavior. The implications of this study are as follows This study examines the effects of university entrepreneurship education on career preparedness behaviors.In other words, the university proved the direct effect and the mediating effect that affects positively (+) effect on career preparation behaviors by encouraging entrepreneurship and self - efficacy, rather than quantitative extension based on competency. Also, the implication of the parameters (entrepreneurship, self - efficacy) as a key variable for the effect and performance of career preparation behavior was derived.It also suggests that it is necessary to improve the creativity ability of entrepreneurship education so that it can have a direct and meaningful influence on career preparation behavior. First of all, it is urgent to develop a qualitative evaluation index for entrepreneurship education in order to measure these effects. Therefore, further study is required to verify the various implications for future entrepreneurship education, as well as the implications that entrepreneurship education is indispensable for the preparation of university students' careers.

• Korean Journal of Pharmacognosy
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• v.13 no.1
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• pp.33-38
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• 1982

In order to investigate the pharmacological action of the combined preparation of crude drugs, 'Saengkankunbi-Tang' were studied. These studies were conducted in an attempt to investigate the effect of 'Saengkankunbi-Tang' on activities of the liver enzyme, protein contents and the excretory action of bile juice in the serum of $CCl_4-intoxicated$ rabbits. The results of this investigate were summarized as follows; GOT, GPT activities and total cholesterol contents in the serum of rabbits induced by $CCl_4$ were shown to the remarkable decrease with the passage of the time in the oral administration of the sample. Albumin contents in the serum of rabbits induce by $CCl_4$ were noted to the significant increase with the passage of the time. Serum total protein contents were noted to the significant increase only the 4th and 6th day. BSP accumulation contents in the serum of rabbits induced by $CCl_4$ showed the remarkable decrease with the passage of the time.

• Analytical Science and Technology
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• v.10 no.2
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• pp.146-152
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• 1997

A rapid BOD measurement system using a microbial membrane electrode has been developed. Culture of microorganism and the preparation of microbial membrane, the effect of sample flow rate on the BOD measurement, the effect of solution pH and response characteristics of the microbial membrane electrode were investigated. The rapid BOD measurement system developed by us was connected to a personal computer and the whole BOD measurement procedures were carried out automatically. The best results were obtained when the solution flow rate was 7.8mL/min and the data were obtained 5 minutes after sample injection.

• Journal of Welding and Joining
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• v.21 no.2
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• pp.97-101
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• 2003

The change of microstructures in the base metal during transient liquid phase bonding process of directionally Ni base superalloy, GID-111 was investigated. Bonds were fabricated using a series of holding times(0~7.2ks) at three different temperatures. The flip chip bonding utilizing self-aligning characteristic of solder becomes mandatory to meet tolerances for the optical device. In this paper, a parametric study of aging condition and pad size of samples was evaluated. A TiW/Cu/electroplated Cu UBM structure was selected and the samples were aging treated to analyze the effect of intermetallic compounds with the time variations. An FIB technique was applied to the preparation of samples for TEM observations. An FIB technique is very useful to prepare TEM thin foil specimens from the solder joint interface. After aging treatment, the tendency to decrease in shear strength was measured and the structure of the solder and the UBM was observed by using SEM, TEM and EDS. As a result, the shear strength was decreased of about 21% in the 100${\mu}{\textrm}{m}$ sample at 17$0^{\circ}C$ aging compared with the maximum shear strength of the sample with the same pad size. In the case of the 12$0^{\circ}C$ aging treatment, 18% of decrease in shear strength was measured at the 100${\mu}{\textrm}{m}$ pad size sample. An intermetallic compound of Cu6Sn5 and Cu3Sn were also observed through the TEM measurement by using.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.577-583
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• 2020

This study analyzed the effect of career preparation behavior of female college graduates on their job satisfaction. The results of this study are as follows: First, the relationship between job satisfaction and career preparation behavior and a regression analysis of job satisfaction were all examined. This study used the original data from the Korea Employment Information Service for '2012 College Graduates' Occupation Route Survey'. The subjects of this study were 1,569 women in the science and engineering fields (649 engineering graduates, and 920 science graduates). The data was analyzed by frequency analysis, independent sample t tests, correlation analysis, and hierarchical multiple regression analysis using SPSS WIN 19.0. As a result, women with 4 years of college have higher job stability and job satisfaction than college students, but the reasons for major selection, university type, college location, and department. The results of this study are as follows. First, the effect of the variables on career satisfaction and job satisfaction was not statistically significant. This suggests that the type of college does not have a significant effect on job satisfaction if the university systematically prepares people for a career and the university suits a person's aptitude.

• Macromolecular Research
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• v.10 no.2
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• pp.127-134
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• 2002

Microporous polypropylene hollow fiber membrane was fabricated from isotactic polypropylene-soybean oil system by melt spinning process. Addition of nucleating agent accelerated the crystallization rate and elevated the crystallization temperature. Nucleating agent increased the number of nuclei and spherulites, which offered more inter-spherulitic amorphous sites for stretching. Benzoic acid, adipic acid, and dibenzylidene sorbitol were selected as nucleating agents, and their characteristics and effects were investigated by thermal and optical analyses. Spherulite growth and micropore formation characteristics were correlated with the kind of nucleating agent. Benzoic acid and adipic acid showed the remarkable nucleating effect, while dibenzylidene sorbitol was less effective than those. Nucleating agents also helped the sample have uniform microporous structure. Increase of nucleating agent composition enhanced the nucleation effect to some extent. Nucleating agents played very important roles in enhancing the membrane porosity and water flux.