• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.12
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• pp.844-861
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• 2008

The papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during the year of 2007 have been reviewed. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro nano fluid, micropump and fuel cell. Traditional CFD was still popular and widely used in research and development. Studies about fans and pumps were performed in the field of fluid machinery. Characteristics of flow and fin shape optimization are studied in the field of piping system. (2) The research works on heat transfer have been reviewed in the field of heat transfer characteristics, heat exchangers, and desiccant cooling systems. The research on heat transfer characteristics includes thermal transport in pulse tubes, high temperature superconductors, ground heat exchangers, fuel cell stacks and ice slurry systems. For the heat 'exchangers, the research on pin-tube heat exchanger, plate heat exchanger, condensers and gas coolers has been cordially implemented. The research works on heat transfer augmenting tubes have been also reported. For the desiccant cooling systems, the studies on the design and operating conditions for desiccant rotors as well as performance index are noticeable. (3) In the field of refrigeration, many papers were presented on the air conditioning system using CO2 as a refrigerant. The issues on the two-stage compression, the oil selection, and the appropriate oil charge were treated. The subjects of alternative refrigerants were also studied steadily. Hydrocarbons, DME and their mixtures were considered and various heat transfer correlations were proposed. (4) Research papers have been reviewed in the field of building facilities by grouping into the researches on heat and cold sources, air conditioning and air cleaning, ventilation and fire research including tunnel ventilation, flow control of piping system, and sound research with drain system. Main focuses have been addressed to the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies were mostly focused on analyzing the indoor environment in various spaces like cars, old tombs, machine rooms, and etc. in an architectural environmental field. Moreover, subjects of various fields such as the evaluation of noise, thermal environment, indoor air quality and development of energy analysis program were researched by various methods of survey, simulation, and field experiment.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.55-65
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• 1999

There have been many reports to date regarding the role of GnRH as a local regulatory factor of ovarian function as studies of human and rat ovaries revealed GnRH and its receptor. In recent studies it has been shown that GnRH directly causes apoptosis in the granulosa cells of the rat ovary, and such results leads to the suggestion that the use of GnRH agonist for more stable long term ovarian hyperstimulation in human IVF-ET programs causes granulosa cell apoptosis which may lead to follicular atresia. Therefore this study attempts to determine if granulosa-luteal cell apoptosis occurs in patients during IVF-ET programs in which GnRH agonist is employed for ovarian hyperstimulation. The quality of oocyte-cumulus complexes obtained during ovum pickup procedures were assessed morphologically and then the fertilization rate and developmental rate was determined. Apoptotic cells among the granulosa-luteal cells obtained during the same procedure were observed after staining with Hematoxylin-eosin. The fragmentation degree of DNA extracted from granulosa-luteal cells was determined and comparatively analyzed. There was no difference in the average age of the patients, the number of oocytes retrieved, and fertilization and developmental rates between the FSH/hMG group and GnRH-long group. There was also no difference in the apoptosis rate and pyknosis rate in the granulosa-luteal cells between the two groups. However, when the oocyte-cumulus complexes were morphoogically divided into the healthy group and atretic group without regard for the method of hyperstimulation, the results showed that the number of oocytes obtained averaged $11.09{\pm}8.75\;and\;10.33{\pm}4.53$ per cycle, respectively, showing no significant difference, but the fertilization rate (77.05%, 56.99%, respectively, p<0.01) and developmental rate (65.96%, 41.51%, respectively, p<0.01) was significantly increased in the healthy group when compared to the atretic group. The degree of apoptosis in the granulosa-luteal cells showed that in the healthy group it was 2.25% which was not significantly different from the atretic group (2.77%), but the pyknosis rate in the atretic group (27.81%) was significantly higher compared to the healthy group (11.35%, p<0.01). The quantity of DNA fragmentation in the FSH/hMG group was 32.22%, while in the GnRH-long group it was 34.27%, showing no significant difference. On the other hand the degree of DNA fragmentation was 39.05% and 11.83% in the healthy group and atretic group, respectively, showing significantly higher increase in the atretic group (p<0.01). The above results suggest that death of granulosa-luteal cells according to the state of the oocyte-cumulus complex is more related to pyknosis rather than apoptosis. Also, the GnRH agonist used in ovarian hyperstimulation does not seem to directly affect the apoptosis of retrieved oocytes and granulosa-luteal cells, and which is thought to be due to the suppression of the apoptogenic effect of GnRH agonist as a result of the high doses of FSH administered.

• The Journal of Natural Sciences
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• v.4
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• pp.143-159
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• 1991

In order to investigate the micropropagation of Pelargonium, 2 cultivars of P. peltatum 'Pouletta' and P. zonale 'Pinto Red' were cultured in vitro on the MS basal medium supplemented with various concentrations of growth regulators. It attempted to study the induction of callus and the differentiation of organs from leaf disc, petiole segments, stem segments. hypocotyle segments and flower stalk segments. The results are summarized as follows; A. As for the initiation of callus, stem explant was proved to be the most suitable one among various explants of P. zonale 'Pinto Red'. The medium was supplemented with 1.0mg/1 BAP and 1.0mg/1 NAA. As NAA concentration increased, callus formation was enhanced, but higher concentration of NAA inhibited callus fromation. Leaf and hypocotyle explants showed less callus formation than stem and petiole explants. B. In P. zonale 'Pinto Red' petiole culture, the condition of cullus culture such as hormone concentration resulted in affecting shoots differentiation. The best result of shoots formation from the callus reculture were obtained from the combination of 0.5-1.0mg/1 BAP and 0.1-1.0mg/1 NAA when the callus was cultured in 1.0mg/1 BAP and 0.05mg/1 NAA. When the callus was cultured in medium without BAP, the shoot was not differentiated in subculture regardless to BAP and NAA concentration. and only callus was formed. C. Poly-phenol substance was observed in MS medium supplemented without PVP, in which callus was not formed from the leaf of P. peltatum 'Rouletta'. Polyphenol substance was not observed in MS medium supplemented with PVP, in which callus formation was increased. D. The callus formation of P. peltatum 'Rouletta' showed the stem explant being best result. The best result particularly in the stem explant among others. The optimal hormonal concentration was 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot formation was observed at 0.05mg/1 NAA and 1.0mg/1 BAP, 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot was malformed and the tissue recultured turned necrotic.

• Food Science and Preservation
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• v.15 no.3
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• pp.450-455
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• 2008

Previously, we have shown that green tea extract lowers the intestinal absorption of cholesterol, fat, and other fat-soluble compounds. We conducted this study to determine whether green tea extract affects the rate of $^{14}C$-oleic acid esterification into various lipids in the intestinal mucosa of rats. Male Sprague-Dawley ruts were had free access to a nutritionally adequate AIN-93G diet and deionized water. Initially, the rat's mucosal content of total lipids was measured following 1 mL olive oil administration with (green tea group) or without (control group) 100 mg green tea extract powder. At 1 h and 5 h, intestinal segments were extracted for total lipid analysis. Secondly, to measure mucosal esterification rates of lipids, an abdominal incision was made along the midline, and a 10-cm long jejunal segment of the small intestine was ligated in situ. Then, micellar solutions with or without green tea extract were injected into the ligated jejunal segments and incubated for 10 mill. The micellar solution contained $200.0\;{\mu}$ Ci $^{14}C$-oleic acid, $200.1\;{\mu}mol$ unlabelled oleic acid, $66.7\;{\mu}mol$ 2-monooleoylglycerol, $66.7\;{\mu}mol$ palmitoyl-sn-glycero-3-phosphocholine, 2.2 mmol glucose, $50.0\;{\mu}mol$ albumin, and 16.5 mmol Na-taurocholate per L of phosphate buffered saline (pH, 6.3) with or without 8.87 g green tea extract powder. At 10 min, each rat was sacrificed by cervical dislocation under anesthesia and the segment was removed for lipid analysis. Significant differences were observed in mucosal triglyceride content at 1 h and 5 h in ruts given green tea extract. Significant differences in the rate of $^{14}C$-oleic acid esterification into triglycerides and phospholipids fractions were observed between control and green tea groups. However, There were no significant differences in other lipid fractions. These results indicate that the lowered esterification rates of $^{14}C$-oleic acid into triglycerides and phospholipids fractions is attributable to presence of green tea extract. This may be associated with an inhibitory effect of green tea catechin on the mucosal processes of lipids, leading to the inhibition of intestinal absorption of lipids.

• International Commerce and Information Review
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• v.13 no.4
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• pp.51-79
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• 2011

Korea has accomplished the establishment of the National Single Window for Paperless Trade. Since 1991, it has developed Trade Automation Service System based on EDI technology. In 2003, Korean government and private sectors jointly began to set up National Paperless Trade Service( e-Trade Service) as one of the e-government projects. In 2008, they commenced the uTradeHub Service which was equipped with Internet based e-B/L and e-Nego service systems for the first time in the world To facilitate the service Korea amended its e-Trade facilitation Act and Law by 2007. At the end of 2011, Korea historically recorded its trade volume of 1 trillion US dollars and joined '$1 trillion trade club' as the 9the member country since the country had started international trade less than five decades ago. A rolling out of the e-B/L and e-Nego service will 'ally reduce the transaction costs of trading businesses and accelerate the activation e-trade services. The purposes of the study are to examine 'e-B/L Korea' service and its facilitation strategies as well as identify obstacles to utilize the 'e-B/L Korea' service. The paper reviewed and analyzed Korea's Paperless trade system and distinctive characteristics of the 'e-B/L Korea Service. Parts of the fOWld distinctive characteristics of the Korea's e-B/L service are as follows; It is well equiped with IT and legal system. It also has more that 30,000 potential users who are already uTradeHub service users. The paper indicated several weaknesses of the current system such as global KPI issues, circulation of the electronic documents not only in the domestic market but also among economies, development of the electronic Bill of Exchange. As resolution measures, the paper recommended the introduction of mutual recognition system of PKI among trade partner counties, setting up e-trade solution for small and medium companies, and special attention to raise users' awareness of the e-B/L service.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.593-603
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• 2012

This study was carried out to investigate the ecological succession sere and conservative value, and to provide the basic data for the planning of the Provincial Park Management in Seonamsagol(Valley), Jogyesan(Mt.) Provincial Park(altitude 884m), Suncheon City, Korea by analysing the structure of the plant community. Twenty plots(size is $20m{\times}20m$) were set up at an altitude of range from 315m to 480m. As a result of analysis of TWINSPAN which is one of the ordination technique, the plant communities were divided into four groups which are community I(Quercus variabilis community), community II(Q. serrata community), community III(Decideous broad-leaved plant community), and community IV(Carpinus tschonoskii community). The warmth index is $104^{\circ}C{\cdot}month$ based on the data of monthly mean temperature during the past thirty years(1981~2010), so we found out that the vegetation of the study site located in the South Temperate Climate Zone. We supposed that the ecological succession sere of the study site is in the early stage of developing from Q. serrata community to Carpinus tshonoskii community, however we should do a long-term monitoring to investigate the changes of the ecological succession each plant community, meanwhile Sasa borealis was dominant species in the shrub layer. The diameter at breast height of specimen tree is range from 20 to 55cm(average 36cm) and the height of that is range from 14 to 35m(average 23cm). The age of community I was 64 years old, that of community II was from 59 to 64 years old, that of community III was from 51 to 62 years old, and that of community IV was from 41 to 68 years old, thus the age of the study site is about from 38 to 72 years old. According to the index of Shnnon's diversity(unit: $400m^2$), community IV was ranged from 0.8452 to 1.2312, community III was ranged from 0.8044 to 1.1404, community II was ranged from 0.8221 to 0.9971, and community I was 0.8324.

• Korean Journal of Ichthyology
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• v.6 no.2
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• pp.132-159
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• 1994

The taxonomic revision of the family Congridae was made based on the specimens collected from the south-western coasts of the Korea from June 1988 to Oct. 1993. The family Congridae was classified into 8 species belonging to 6 genera. based on the external and internal morphological characters : Anago anago, Ariosoma anagodies, Ariosoma shiroanago shiroanago, Conger myriaster, Conger japonicus, Gnathophis nystromi nystromi, Rhechias retrotincta and Uroconger lepturus. Among the species reported as the congrid eels from Korea until now, four species were transferred into different generic or specific name Conger flavirostris into Ariosoma anagoides ; Astroconger myriaster into Conger myriaster ; Congrina retrotincta into Rhechias retrotincta and Rhynchocymba nystromi into Gnathophis nystromi nystromi. A Korean congrid eel, Ariosoma shiroanago shiroanago, was reported for first time in Korea. Intergeneric characters of the family Congridae were the form of the lateralline scales, the state of the tip of tail, the segmented state of the dorsal and anal fin rays, the existance of the supraoccipital bone and of lateral ethmoid process of the skull, the origin of dorsal fin and the forms of upper labial flange. The interspecific classification was made according to the characters such as the numbers of sensory pores of head part and in front of vent, teeth rows and numbers of upper and lower jaw, the numbers of vertebrae, the body color, the shapes of the head part, the color of intestine, the size of eye, the structure of air bladder and the number of branchiostegal rays. A new key on the taxonomical characteristics to the genera and species of the family Congridae has been estabilished and their distribution in Korea is described.

• Journal of agricultural medicine and community health
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• v.26 no.1
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• pp.1-17
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• 2001

This study was conducted to investigate the role of drinking pattern in the relationship of alcohol consumption by face-to-face interview in rural elderly(n=994) aged 60~64 in Dalsung County, April to September in 1996. Pattern of alcohol drinking included drinking status, alcohol drinking at the morning without breakfast, average drinks per day, frequency of drinks per month, quantity of alcohol drinking, kind of preferred alcoholic beverage and duration of alcohol drinking. Blood pressure was measured once in each subject using a portable automatic sphygmomanometer. Difference in means of systolic blood pressure, alcohol drinking status, alcohol drinking at the morning without breakfast, and kind of alcoholic beverage were statistically significant before adjusting covariates, but alcohol drinking status and alcohol drinking at the morning without breakfast were statistically significant after adjusting covariates. And difference in means of diastolic blood pressure, kinds of alcoholic beverage was statistically significant before adjusting covariates, but no variables was significant after adjusting covariates. Model I multiple regression for systolic blood pressure that included average drinks per day as the variable of drink pattern, age, educational attainment and, previous history of cardiovascular disease were statistically significant, and multiple regression for diastolic blood pressure, educational attainment, BMI, and previous history of cardiovascular disease were statistically significant. Model II multiple regression for systolic blood pressure that included drinking patterns variables except average drinks per day, previous history of cardiovascular disease were statistically significant. However, multiple regression for diastolic blood pressure, no variables were significant. So, inconsistent with prior research, a positive relationship was not found between average drinks per day and diastolic and systolic blood pressure. The effect of alcohol drinking patterns on blood pressure has public health as well as clinical relevance. The study should be replicated to determine the reliability of our findings.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.1
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• pp.23-31
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• 2013

Microwave remote sensing can help monitor the land surface water cycle and crop growth. This type of remote sensing has great potential over conventional remote sensing using the visible and infrared regions due to its all-weather day-and-night imaging capabilities. In this paper, a ground-based multi-frequency (L-, C-, and X-band) polarimetric scatterometer system capable of making observations every 10 min was developed. This system was used to monitor the wheat over an entire growth cycle. The polarimetric scatterometer components were installed inside an air-conditioned shelter to maintain constant temperature and humidity during the data acquisition period. Backscattering coefficients for the crop growing season were compared with biophysical measurements. Backscattering coefficients for all frequencies and polarizations increased until dat of year 137 and then decreased along with fresh weight, dry weight, plant height, and vegetation water content (VWC). The range of backscatter for X-band was lower than for L- and C-band. We examined the relationship between the backscattering coefficients of each band (frequency/polarization) and the various wheat growth parameters. The correlation between the different vegetation parameters and backscatter decreased with increasing frequency. L-band HH-polarization (L-HH) is best suited for the monitoring of fresh weight (r=0.98), dry weight (r=0.96), VWC (r=0.98), and plant height (r=0.96). The correlation coefficients were highest for L-band observations and lowest for X-band. Also, HH-polarization had the highest correlations among the polarization channels (HH, VV and HV). Based on the correlation analysis between backscattering coefficients in each band and wheat growth parameters, we developed prediction equations using the L-HH based on the observed relationships between L-HH and fresh weight, dry weight, VWC and plant height. The results of these analyses will be useful in determining the optimum microwave frequency and polarizations necessary for estimating vegetation parameters in the wheat.

• Management & Information Systems Review
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• v.31 no.4
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• pp.237-260
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• 2012

Purposes of this paper are focused on researching that employees in small and medium-sized construction company embraced green growth policy by Korean government's strong will and they have try to improve it to take advantage of strengths. Specifically, the purpose of this study includes: Firstly, to examine the effects of employee's cognition of green growth policy and their organizational commitment. Secondly, to examine the mediating and moderating effect of the policy trust and company trust between employee's cognition of green growth policy and organizational commitment. In addition, th examine the facilitating effect of employee's self-efficacy between company trust and organizational commitment. In order to verify the relationship, moderating and mediating effects, data were collected from 168 individuals in 19 small and medium sized company to test theoretical model and its hypotheses. Findings are as followed: first, the relationship between the cognition of green growth policy and organizational commitment is positively related. Second, the employee's company trust played as a partial mediator and moderator on the relationship between cognition of green growth policy and organizational commitment. Finally, employee's self-efficacy also played as a partial mediator on the relationship between company trust and organizational commitment. This study contributes to deepen our understanding of employee's organizational commitment by suggesting an alternative theoretical model regarding how the cognition of green growth policy and organizational commitment work to relate employee's company trust, and how the company trust and organizational commitment work to facilitate employee's self-efficacy. These results reveal that the study contributed to combining variables of employee's cognition of green growth policy, company trust, self-efficacy and organizational commitment, and expanded it.