• Korean Journal of Animal Reproduction
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• v.18 no.1
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• pp.15-23
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• 1994

This study was carried out to investigate the effects of concentration, kinds of cryoprotectants, equilibration time, optimum thawing temperature on the survival rate of rapidly frozen porcine embryos. The porcine embryos following dehydration by cryoprotectants containing sucrose were directly plunged into liquid nitrogen and thawed in 30, 35 or 37$^{\circ}C$ water bath, Survival rate was defined as development rate on in vitro culture or FDA-test. The results are summarized as follows : 1. The high survival rate of porcine frozen embryos after rapidly thawed in freezing medium was attained 2.0M DMSO, 2.0M glycerol, 2.0M propanediol, 1.5M ethyleneglycol. 2. The high survival rate of porcine frozen embryos after rapidly thawed in freezing medium was obtained using single cryoprotectant(16.6~40.0%) than mixed cryoprotectants(12.5~33.3%). 3. The eqilibration time on the survival rate of rapidly thawed porcine frozen embryos was attained after short period of time(15.0~33.3%) in the freezing medium higher than long period of time(9.10~30.0%). 4. The thawing temperature on the survival rate of rapidly thawed porcine frozen embryos was attained at 3$0^{\circ}C$ of thawing temperature(33.3~40.6%) in the freezing medium higher than 25 or 37$^{\circ}C$ of thawing temperature.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.392-396
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• 2009

Protocorms were newly formed from the culture of axillary buds, obtained in the seedlings of Dendrobium moniliforme in vitro. Its formation ratio was calculated to 43.7% on MS medium containing 1.0 mg/L BA. To test their survival ratio, we gradually increased the inoculation of transplant populations from single to more than three, and then found that the ratio in three populations went up as high as 95.2% rather than those of one or two. In bioreactor, explant obtained from the axillary bud grew well in lower concentration as 1/4 MS medium, while clearly grew slow in a little bit high concentration as 1/2 MS medium. We found that the explant of axillary bud, obtained from the Dendrobium moniliforme seedlings, would grow five times after culturing in a bioreactor for six weeks in 1/4 MS medium.

• Korean Journal of Occupational Health Nursing
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• v.4
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• pp.30-38
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• 1995

The purpose of this study was to evaluate the effect of health services on workers with hypertension in small and medium sized enterprises (20-300 employees). One hundred seventy three workers among 296 workers with hypertension were responded to the questionnaire on general and occupational characteristics, health habits and anti-hypertensive medications. Blood pressure was obtained while seated using a calibrated standard manometer before and after 4 months health services. Statistical analysis was performed using $X^2$-test and logistic regression analysis. The results were as follows ; 1. No significant differences were noted in variables of smoking, glucose intake and sleeping time, while significant differences were showed in variables of exercise time, frequency and amount of drinking and intake of salt, protain, lipid, calcium, vegetable and fruits between groups which was provided and not provided health services. 2. The rate of anti-hypertensive medication was increased and the blood pressure was decreased significantly in group which was provided health services compared with those of group which was not provided. 3. With the logistic regression analysis, significant variables affecting blood pressure change were smoking and anti-hypertensive medication. The results of this study suggested that health services on workers with hypertension in small and medium sized enterprises was effective, and the role of health professionals for health promotion movement in enterprises was important.

• Journal of Biomedical Engineering Research
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• v.34 no.1
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• pp.34-39
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• 2013

For the biocompatibility test of implantable devices or for the sensitivity evaluation of biomedical sensors, it is required to understand the mechanism of the protein adsorption and the interaction between the adsorbed proteins and cells. In this study, the adsorption of proteins in a cell culture medium with fetal bovine serum onto an indium tin-oxide electrode was characterized by using linear sweep voltammetry and impedance spectroscopy. We immersed the fabricated ITO electrodes in the culture medium for 30, 60, or 90 min, and then measured the electrochemical properties of electrodes with 10 mM $Fe(CN){_6}^{3-/4-}$ and 0.1 M KCl electrolyte. With an increase of contacting time, the anodic peak current was decreased and the charge transfer resistance was increased. However, both parameters were recovered to the values before contact with the medium after the treatment of Trypsin/Ethylenediaminetetraacetic acid hydrolyzing proteins.

• Journal of Korean Academy of Nursing Administration
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• v.22 no.2
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• pp.158-166
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• 2016

Purpose: This study was done to investigate the influence of organization and community job embeddedness on turnover intention of nurses in small and medium sized general hospitals. Methods: The participants, 333 nurses, were recruited from small and medium sized general hospitals in Korea. Data were collected by self-report questionnaires on job-embeddedness and turnover intention and were analyzed using descriptive statistics, Independent t-test, One-way ANOVA and $Scheff{\acute{e}}^{\prime}$, Pearson correlation coefficient, and multiple linear regression analysis with the SPSS 18.0 program. Results: The score for job embeddedness and it's 6 factors, and turnover intention were above 3 on a 5 point scale with the exception of organizational sacrifice. There was a significant difference in turnover intention according to age, marital status, salary, and position. There were significant negative correlations between the 6 factors of job embeddedness and turnover intention. Variables entered in multiple regression showed that organizational sacrifice, organizational fit and age were significant contributing factors to turnover intention. Conclusion: The findings suggest that there is a need for strategies to enhance job embeddedness, especially organization sacrifice and organization fit. These factors should be developed and used to decrease turnover intention of nurses in small and medium sized general hospitals.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.6
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• pp.409-416
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• 2005

For broadband high-data-rate power line communication with the allocated frequency bandwidth from 2 to 30 MHz on medium voltage (MV) distribution power lines, a signal coupling unit is developed. The coupling unit is composed of a coupling capacitor for coupling communication signal, a drain coil, and an impedance matching part. The coupling capacitor made of ceramic capacitor is designed for transmission property of better than 1 dB in the frequency range. The drain coil is used for preventing low frequency high voltage from junction of medium voltage power line in case that a coupling capacitor is not working properly any more. Also, using ferrite core, a novel broadband impedance matching transformer is developed. A complete coupling unit with a coupling capacitor, a drain coil, and a matching transformer is housed by polymer for good isolation and distinguishing from high voltage electric facilities. Each is fabricated and its frequency behavior is tested. Finally, complete signal couplers are equipped in a MV PLC test bed and their performance are measured. The measurement shows that the coupling capacitor works excellently.

• Journal of the Korean Home Economics Association
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• v.34 no.3
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• pp.47-57
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• 1996

Ther purpose of this study was to investigate the perceptual differences in brand images of national medium-low price casual clothing according to purchase volume and brand loyalty. Additionally, differences between Seoul and County of Chungnam in purchase volume of each brand of medium-low priced casual, information source and companion in purchasing the brands were analyzed. The questionnaires were administered to 540 college student living in Seoul and County of Chungnam, and the method used to analyze the data were frequency, factor analysis, and t-test. The results were as follows: 1) Perceptual mapping showed that preference ranks among the six brands were same regardless of purchase volume and brand loyalty, but heavy users and loyal consumers to medium-low priced casual brands had more favorite brand image than light users and non loyal consumers. 2) Those who live in County of Chungnam purchased all six brands more than those who love in Seoul with the exception of Hunt. Information sources such as catalogs and celebrity were more used in County of Chungnam. Most accompanied shopping alone both in Seoul and County of Chyngnam, however family members were more influential in Seoul, whereas the same sex friends were in County of Chyngnam.

• Journal of Power Electronics
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• v.10 no.2
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• pp.155-164
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• 2010

This paper presents a voltage control algorithm for a hybrid multilevel inverter based on a staged-perception of the inverter voltage vector diagram. The algorithm is applied to control a three-stage eighteen-level hybrid inverter, which has been designed with a maximum number of symmetrical levels. The inverter has a two-level main stage built using a conventional six-switch inverter and medium- and low- voltage three-level stages constructed using cascaded H-bridge cells. The distinctive feature of the proposed algorithm is its ability to avoid the undesirable high switching frequency for high- and medium- voltage stages despite the fact that the inverter's dc sources voltages are selected to maximize the number of levels by state redundancy elimination. The high- and medium- voltage stages switching algorithms have been developed to assure fundamental switching frequency operation of the high voltage stage and not more than few times this frequency for the medium voltage stage. The low voltage stage is controlled using a SVPWM to achieve the reference voltage vector exactly and to set the order of the dominant harmonics. The inverter has been constructed and the control algorithm has been implemented. Test results show that the proposed algorithm achieves the desired features and all of the major hypotheses have been verified.

• The Korean Journal of Health Service Management
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• v.13 no.2
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• pp.27-38
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• 2019

Objectives: The purpose of this study was to investigate the relationship between medical service quality, emotional attachment, customer satisfaction, and customer behavioral intention of small and medium hospitals. Methods: 228 patients who have used small and medium hospitals' medical services were selected. The analysis methods used were confirmatory factor analysis, validation of discrimination, path analysis, and bootstrapping using SPSS 23 and AMOS 23. Results: As a result of the hypothesis test, reliability, responsiveness, and assurance were found to have a positive (+) influence on emotional attachment and customer satisfaction, while empathy had a positive (+) influence on emotional attachment only. Emotional attachment had a positive (+) influence on customer satisfaction and behavioral intention, and customer satisfaction had a positive (+) influence on behavioral intention. Conclusions: Medical service providers in small and medium hospitals should recognize that increasing customer satisfaction based on emotional attachment is a pathway to customer acquisition and, ultimately, a way to promote effective management.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.5
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• pp.273-286
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• 2010

The main purpose of this study was to demonstrate the most common characteristics of the small and medium system integration companies in performing IT projects. In this study, 388 auditing reports on the 194 IT projects which were carried out by the small and medium size manufacturers from 2006 to 2009 were employed and surveyed. This survey revealed that the schedule management was the most neglected item in the project management area, the test planning and action was the most neglected item in the development and coding area, and the manual preparation for users and operators was the most neglected item in the operation and maintenance area. Consequently these three most neglected items were considered as the most common characteristics of the small and medium system integration companies in performing IT projects.