• Journal of Photoscience
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• 제9권2호
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• pp.9-12
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• 2002

Circadian rhythms can be seen in a variety of physiological functions in insects. Light is a powerful zeitgeber not only synchronizing but also modulating the rhythm to adjust insect's temporal structure to seasonal changes in the environmental cycle. There are two general effects of the length of light phase within 24 hr light cycles on the circadian rhythms, i.e., the modulation of free-running period and the waveform. Since the photoperiodic modulation of the free-running period is induced even in the clock mutant flies, per$\^$s/, the free-running period is not fully determined genetically. In crickets, the ratio of activity (a) and rest phase (p) under the constant darkness (DD) is clearly dependent on the photoperiod under which they have been kept. When experienced the longer photoperiod it becomes smaller. The magnitude of change in a/p-ratio is dependent on the number of cycles they experienced. The neuronal activity of the optic lobe in DD shows the a/p-ratio changing with the preceding photoperiod. These data suggest that a single circadian pacemaker stores and maintains the photoperiodic information and that there is a system that accumulates the effects of single photoperiod to cause greater effects.

• 한국수소및신에너지학회논문집
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• 제16권3호
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• pp.269-276
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• 2005

Zn, Bi 와 V 금속이온 전구체를 사용하여 모노클리닉 결정구조를 갖는 신규 ZnBiVO4 광촉매를 손쉽게 합성 할 수 있는 방법을 개발하였다. 합성된 $ZnBiVO_4$ 광촉매는 XRD 과 FESEM등을 이용하여 미세구조를 분석하였으며, 분석결과 본 삼성분계 금속산화물 반도체 광촉매는 모노클리닉 결정구조를 갖는 것을 알 수 있었다. 저온 수용액방법에 의해 손쉽게 나노 구조를 갖는 $ZnBiVO_4$가 제조되었으며, 그 광촉매의 최소 입자크기는 20-30 nm 이다. $ZnBiVO_4$ 광촉매는 UV-visible DRS (diffuse reflectance spectroscopy)로 그 띠간격(band gap)을 측정하였으며, FT-IR을 사용하여 구조 및 물질 상의 순도를 확인하였다. 그리고 $H_2S$를 광분해하여 수소를 발생하는($122ml/hr{\cdot}g$) 우수한 광촉매 활성을 보여 주었다.

• 전자공학회논문지A
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• 제32A권11호
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• pp.35-43
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• 1995

To obtain high quality of $Ta_{2}O_{5}$ film, two dielectric layers of $Si_{3}N_{4}$ and $Ta_{2}O_{5}$ were subsequently formed on Si wafer. Silicon nitride films were thermally grown in 10 Torr ammonia ambient by R.F induced heating system. The thickness of thermally grown $Si_{3}N_{4}$ film was able to be controlled in the range of tens $\AA$ due to the self-limited growth property. $Ta_{2}O_{5}$ film of 200$\AA$ thickness was then deposited on the as-grown $Si_{3}N_{4}$ film about 25$\AA$ thickness by sputtering method and annealed at $900^{\circ}C$in $O_{2}$ ambient for 1hr. Stoichiometry film was prepared by the annealing in oxygen ambient. Despite the high temperature anneal process, silicon oxide layer was not grown at the interface of the layered films because of the oxidation barrier effect of Si$_{3}$N$_{4}$ film. The fabricated $Ta_{2}O_{5}$/$Si_{3}N_{4}$ film showed low leakage current less than several nA and high dielectric breakdown strength.

• 한국환경과학회지
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• 제3권4호
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• pp.393-402
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• 1994

It is necessary to examine the source contributions and the relationship between a receptor and sources for the resonable controlling of air pollution level of suspended particulate matters. Therefore, in this study, profiles of sources contributing to the concentration of suspended particulate matters, were developed and CMB model was applied to obtain information of source contributions and feasibility of CMB model application. According to the propose of this study, twenty-seven chemical species such as the elements, anions, and total carbon of thirty-six PMl0 and TSP data sets sampled at the Pomch'on receptor site in Pusan for a 24-hr period from May to Aug. 1992, were analyzed and three (transportation, soil, marine) different source profiles were developed through the field measurement. Applying CMB model to transportation, soil, marine, the results of source contribution by CMB model showed that the case with TSP was more suitable for CMB model than that with PMl0. And the average contribution of transportation source to TSP and PMlo concentration at Pomch'on receptor was calculated as 90.66 ㎍/m3(64%) and 23.27 ㎍/m3(39%), resfiectively, which showed that the contribution by transportation was dominant. The validation of CMB model was performed by means of the results of contributions from marine source for the wind direction sectors.

• 대한지역사회영양학회지
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• 제10권1호
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• pp.79-90
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• 2005

This study was performed to estimate serum 25-hydroxyvitamin D level and to evaluate the relationship between serum 2S-hydroxyvitamin D level and associated factors. The subjects were 61 premenopausal working women aged 30 - 49 y in Busan. The serum 25-hydroxyvitamin D level was measured by radioimmunoassay. Data for physiological characteristics, lifestyle factors, physical activity and nutrient intake were assessed by questionnaire including information about outdoor activity time, daily activity diary and 24 hr recall method. The mean vitamin D intake was 3.12 ug, which corresponded to $62.5\%$ of the Korean RDA. The mean level of serum 25-hydroxyvitamin D was 31.0 ng/mL. Low 25-hydroxyvitamin D (<25 nmol/L) was not found in the subjects. The serum 2S-hydroxyvitamin D level showed positive significant correlations with exercise hours, daily energy expenditure, hours of outdoor activity per weekdays (p < 0.001, P < 0.05, P < 0.05). Exercise hours were found to be the most important determinant of serum 25-hydroxyvitamin D level. Therefore nutritional education for increasing hours of physical activity including indoor and outdoor exercise, is needed for premenopausal working women to increase vitamin D status.

• International Journal of Vascular Biomedical Engineering
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• 제2권2호
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• pp.16-26
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• 2004

The object of this study is to develop a mathematical model of the hemodialysis system including the mechanism of solute kinetics, water exchange and also cardiovascular dynamics. The cardiovascular system model used in this study simulates the short-term transient and steady-state hemodynamic responses such as hypotension and disequilibrium syndrome (which are main complications to hemodialysis patients) during hemodialysis. It consists of a 12 lumped-parameter representation of the cardiovascular circulation connected to set-point models of the arterial baroreflexes, a kinetic model (hemodialysis system model) with 3 compartmental body fluids and 2 compartmental solutes. We formulate mathematically this model in terms of an electric analog model. All resistors and most capacitors are assumed to be linear. The control mechanisms are mediated by the information detected from arterial pressoreceptors, and they work on systemic arterial resistance, heart rate, and systemic venous unstressed volume. The hemodialysis model includes the dynamics of urea, creatinine, sodium and potassium in the intracellular and extracellular pools as well as fluid balance equations for the intracellular, interstitial, and plasma volumes. Model parameters are largely based on literature values. We have presented the results on the simulations performed by changing some model parameters with respect to their basal values. In each case, the percentage changes of each compartmental pressure, heart rate (HR), total systemic resistance (TSR), ventricular compliance, zero pressure filling volume and solute concentration profiles are represented during hemodialysis.

• 대한간호학회지
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• 제41권4호
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• pp.471-480
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• 2011

Purpose: The purpose of this study was to evaluate the effectiveness of the Permission, Limited Information, Specific Suggestions, Intensive Therapy (PLISSIT) model sexual program on female sexual function for women with gynecologic cancer. Methods: The integrative 6-hr (two hours per session) program reflecting physical and psychosocial aspects of women's sexuality was developed based on Annon's PLISSIT model. Participants were 61 women with cervical, ovarian, or endometrial cancer. Of them, 29 were assigned to the experimental group and 32 to the control group. The women completed the Female Sexual Function Index (FSFI) including sexual desire, arousal, lubrication, orgasm, satisfaction, and pain. Independent t-test and repeated measured ANOVA were used to test the effectiveness of the program. Results: Significant group differences were found on FSFI sub-domain scores including sexual desire, arousal, lubrication, orgasm, and satisfaction but not pain. Significant time differences were found on all domains except for pain in the experimental group repeated measured ANOVA. Conclusion: The results indicate that the three-week PLISSIT model sexual program is effective in increasing sexual function for women with gynecologic cancer. Nurses may contribute to improving women's sexual function by utilizing the program. Strategies to relieve sexual pain need to be considered for greater effectiveness of the program.

• Journal of Nutrition and Health
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• 제32권6호
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• pp.713-725
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• 1999

Women have a greater incidence of coronary heart disease(CHD) after menopause. It relates to hormone imbalance-induced changes in known CHD risk factors, especially hyperlipidemia. Accordingly, once women are diagnosed, the rate of morbidity and mortality is greater than for men. Thus, preventive strategies are critical to improve the quality oflife in the later years for women. The purpose of ths study was to explore the difference of anthropometric, environmental factors and food behaviors between normocholesterolemia and hypercholesterolemia within postmenopausal women. The subjects were classified as normocholesterolemia and hypercholesterolemia based on the Guideline for Korean Hyperlipidemia. The results obtained are summarized as follows. The distributions of general characteristics such as age, family income, occupation status, age at menarche, and menopausal period were not significantly different between the normocholesterolemia group and hypercholesterolemia group. The anthropometric factors such as body mass index(BMI) and waist hip ratio(WHR) were not significantly different between the normocholesteroemia group and the hypercholesterolemia group but odds ratio of hypercholesterolemia group was higher than that of normocholesterolemia but not significant. Aerobic activity more than 1hours/day was significantly related to low serum cholesterol concentration. Eating behaviors related to regular meal time, regular breakfast habit, and slow meal speed were related to low serum cholesterol concentration. Eating the chicken without skin was significantly related to low serum cholesterol concentration. Our data indicate that desirable eating habit, aerobic activity more than 1hr/day are important factors of serum cholesterol concentrations in postmenopausal women. The result of this study provide information that is important in designing appropriate dietary guidelines for hypercholesterolemia in postmenopausal women.

• 한국분말재료학회지
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• 제16권4호
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• pp.268-274
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• 2009

For the purpose of obtaining basic information on the development of lead-free materials, a high density composites (a) W-Cu, (b) W-Sn (c)W-Cu-Sn and (d) W-Cu-Ni were fabricated by the P/M method. The particle size of used metal powders were under 325 mesh, inner size of compaction mould was $\phi8$ mm, and compaction pressure was 400 MPa. A High density composite samples were sintered at a temperature between $140^{\circ}C$ and $1050^{\circ}C$ for 1 hour under Ar atmosphere. The microstructure, phase transformation and physical properties of the sintered samples were investigated. As the results, the highest relative density of 95.86% (10.87 g/$cm^3$) was obtained particularly in the sintered W-Cu-Sn ternary system sample sintered at 450 for 1hr. And, Rockwell hardness (HRB) of 70.0 was obtained in this system.

• Asian Journal of Business Environment
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• 제4권1호
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• pp.5-13
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• 2014

Purpose - This study examines the relationship between organizational justice and employee job satisfaction and the extent of its moderation by perceived alternative job opportunities. Research design, data, and methodology - This is a cross-sectional study utilizing survey questionnaire data from 220 bank employees, which included scales measuring organizational justice, job satisfaction, and perceived alternative job opportunities. Results - The data is analyzed using correlation and hierarchical regression. Results demonstrated that organizational justice has a direct positive impact on employee job satisfaction further, distributive justice explains more variance in job satisfaction, followed by procedural justice and interactive justice. Perceived alternative job opportunities moderate the relationship between organizational justice and job satisfaction. Conclusions - Generally, organizational justice increases bank employees' job satisfaction; however, when they perceived more job opportunities, their job dissatisfaction increased notwithstanding fairness. Therefore, perceived job opportunities moderate the relationship between organizational justice and job satisfaction. Retaining skilled employees has become difficult, especially when there is market demand for skilled workers. Human resource (HR) managers should consider market situations before formulating policies; otherwise, they may lose the competitive advantage of skilled employees and workers.