• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.1
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• pp.1-10
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• 2016

Currently available surface seawater partial pressure carbon dioxide ($pCO_2$) data sets in the East Sea are not enough to quantify statistically the carbon dioxide flux through the air-sea interface. To complement the scarcity of the $pCO_2$ measurements, we construct a neural network (NN) model based on satellite data to map $pCO_2$ for the areas, which were not observed. The NN model is constructed for the Ulleung Basin, where $pCO_2$ data are best available, to map and estimate the variability of $pCO_2$ based on in situ $pCO_2$ for the years from 2003 to 2012, and the sea surface temperature (SST) and chlorophyll data from the MODIS (Moderate-resolution Imaging Spectroradiometer) sensor of the Aqua satellite along with geographic information. The NN model was trained to achieve higher than 95% of a correlation between in situ and predicted $pCO_2$ values. The RMSE (root mean square error) of the NN model output was $19.2{\mu}atm$ and much less than the variability of in situ $pCO_2$. The variability of $pCO_2$ with respect to SST and chlorophyll shows a strong negative correlation with SST than chlorophyll. As SST decreases the variability of $pCO_2$ increases. When SST is lower than $15^{\circ}C$, $pCO_2$ variability is clearly affected by both SST and chlorophyll. In contrast when SST is higher than $15^{\circ}C$, the variability of $pCO_2$ is less sensitive to changes in SST and chlorophyll. The mean rate of the annual $pCO_2$ increase estimated by the NN model output in the Ulleung Basin is $0.8{\mu}atm\;yr^{-1}$ from 2003 to 2014. As NN model can successfully map $pCO_2$ data for the whole study area with a higher resolution and less RMSE compared to the previous studies, the NN model can be a potentially useful tool for the understanding of the carbon cycle in the East Sea, where accessibility is limited by the international affairs.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.69-79
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• 2018

The Korean government attempts to reduce $CO_2$ emissions by 37% to 314.7 Mt $CO_2$, down from the estimated 850.6 Mt $CO_2$ until 2030 in order to confront green house effect. In this context, in 2014, Korean government launched $CO_2$ Storage Environmental Management Research (K-COSEM) Center for carrying out pilot-scale research on $CO_2$ leakage from underground $CO_2$ storage facilities. For the detection of $CO_2$ leakage, it is necessary to identify hydrologeological and geophysical characteristics of the subject area. In the study site of Naesan-ri, Daeso-myeon, Eumseong-gun, Chungbuk Province, two times injection tests (June 28-July 24, 2017 and August 07-September 11, 2017) of $CO_2$ and $SF_6$ dissolved waters, respectively, was conducted to understand the leakage behavior of $CO_2$ from underground. The injection well was drilled to a depth of 24 m with a 21-m casing and screen interval of 21~24 m depth. Two times resistivity surveys on August 18, 2017 and September 1, 2017, were conducted for revealing the flow of the injected water as well as the electrical properties of the study site. The study results have shown that the high-resistivity zone and the low-resistivity zone are clearly contrasted with each other and the flow direction of the injected water is similar to natural groundwater flow. Besides, the low resistivity zone is widely formed from the depth of injection to the shallow topsoil, indicating that the weathered zone of high permeability has high $CO_2$ leakage potential.

• Journal of the Korean Society of Food Culture
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• v.6 no.4
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• pp.393-401
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• 1991

In order to compare the food consumption pattern of college girls on weekday and Sunday, the food intake of college girls in a district of Pusan city was analyzed through the factor analysis method. The principal results are as follows. 1. The amount of food intake on Sunday was generally larger than the average values of the food intake on weekday except for soybean & products, meats and beverage. 2. As for correlation coefficients among the intake of each food group, on weekday, positive correlation was noted among rice, potatoes, soybean & products and sea-weeds, fish & shells and fat & oil. And confectionery & sugar showed also a positive correlation to bread, while, on Sunday, vegetables, sea-weeds and meats showed a positive correlation to rice, and other cereals and eggs showed a positive correlation to bread & noodles, too. As for the relationship among rice and bread & noodles, a negative correlation was noted both on weekday and Sunday. 3. As for the factor analysis of the food intake on weekday through the correlation matrix, in the first factor, soybean & products, fat & oil, sea-weeds, rice and fish & shells showed comparatively large factor load, and in the second factor, meats, kimchi, vegetables, soybean & products, fruits and fish & shells showed large factor load. Here the first factor showed the Korean dietary life and the second factor showed subsidiary food (control nutrient) factor. In case of the food intake on Sunday, in the first factor, rice, meats, sea-weeds, soybean & products and vegetables showed large factor load, and in the second factor, fish & shells, vegetables, fat & oil, fruits and rice showed large factor load. Accordingly, the first factor and the second factor were considered to show Korean dietary pattern. 4. Nutrient intake on weekday and Sunday was substantially sufficient to RDA except for energy and iron.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.404-412
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• 1994

Radium isotopes were measured together with oceanographical parameters in the southern coastal region of the Korean East Sea during the period of September $2{\sim}8$, 1991. In September, there were various water masses vertically distributed in this region due to formation of strongly seasonal thermoclines. These water masses were characterized by activity of radium isotopes as well as water temperature and dissolved oxygen. Among the water masses, Japan Sea Proper Water(JSPW) below $1^{\circ}C$ had the highest Ra-226 activities but the lowest Ra-228 concentrations. However, Tsushima Surface Water (TSW) above $20^{\circ}C$ in water temperature had the highest Ra-228 which decreased sharply with depth. In TSW, Ra-228 activities were in the range of $194{\sim}270$ dpm/kl, which were approximately 10 times higher than JSPW. Activity ratios(A.R's) of Ra-228/Ra-226 were $1.9{\sim}2.6$ for TSW, $0.7{\sim}1.1$ for Tsushima Middle Water(TMW) of $12{\sim}17^{\circ}C\;to\;0.4{\sim}0.7$ for North Korea Cold Water(NKCW) with $1{\sim}7^{\circ}C$ and below 0.2 for JSPW. The Ra-228/Ra-226 ranged from 0.6 to 0.9 in the cold waters of $2{\sim}6^{\circ}C$, which were observed at depth of $65{\sim}120\;m$ in this study area. Radium isotopes provided a useful means of identifying origins of the cold water which occurred annually at intermediate or bottom layers in the southern coastal zone of the Korean East Sea. By plotting radium isotopes against water temperature, it could be observed clearly that the cold waters between $2{\sim}6^{\circ}C$ did not originate from the mixed water of JSPW and TMW but from NKCW.

• Korean Journal of Remote Sensing
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• v.36 no.2_2
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• pp.351-363
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• 2020

It is well known that alluvial sediment located in coastal region has been easily affected by geohazard like ground subsidence, marine or meteorological disasters which threaten invaluable lives and properties. The subsidence is a sinking of the ground due to underground material movement that mostly related to soil compaction by water extraction. Thus, continuous monitoring is essential to protect possible damage from the ground subsidence in the coastal region. Radar interferometric application has been widely used to estimate surface displacement from phase information of synthetic aperture radar (SAR). Thanks to advanced SAR technique like the Small BAseline Subset (SBAS), a time-series of surface displacement could be successfully calculated with a large amount of SAR observations (>20). Because the ALOS-2 PALSAR-2 L-band observations maintain higher coherence compared with other shorter wavelength like X- or C-band, it has been regarded as one of the best resources for Earth science. However, the number of ALOS-2 PALSAR-2 observations might be not enough for the SBAS application due to its global monitoring observation scenario. Unfortunately, the number of the ALOS-2 PALSAR-2 Stripmap images in area of our interest, Busan which located in the Southeastern Korea, is only 11 which is insufficient to apply the SBAS time-series analysis. Although it is common that the radar interferometry utilizes multiple SAR images collected from same acquisition mode, it has been reported that the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application could be possible under specific acquisition mode. In case that we can apply the Stripmap-ScanSAR interferometry with the other 18 ScanSAR observations over Busan, an enhanced time-series surface displacement with better temporal resolution could be estimated. In this study, we evaluated feasibility of the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application using Gamma software considering differences of chirp bandwidth and pulse repetition frequency (PRF) between two acquisition modes. In addition, we analyzed the interferograms with respect to spectral shift of radar carrier frequency and common band filtering. Even though it shows similar level of coherence regardless of spectral shift in the radar carrier frequency, we found periodic spectral noises in azimuth direction and significant degradation of coherence in azimuth direction after common band filtering. Therefore, the characteristics of spectral bandwidth in the range and azimuth direction should be considered cautiously for the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometry.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.15-26
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• 2015

The purpose of this study was to examine the area, theme and method of domestic articles on the successful establishment of venture companies, which were presented between 1998 and 2014, according to related basic classification criteria in an effort to shed light on the characteristics of these studies. It's basically meant to make a contribution to the development of research on the success of venture business and to be of practical use for the success of venture companies in our country. After related earlier studies were analyzed, 164 articles were collected, and 64 articles were selected from among them. The articles that were overlapped, not presented or not registered were excluded. The related studies had been conducted by different learned societies that were interested in the same research themes, and the studies were primarily led by the Korean Society of Business Venturing as of 2014, especially by Asia-Pacific Journal of Business Venturing and Entrepreneurship that was a journal published by this society. This society seemed to have taken the initiative in this field. There was a tendency that the related studies increased in number due to the shifts of modern industrial society and the changing policies of the government, as the number of the studies has been on the steady rise since 2012. In terms of method, quantitative research methods, especially descriptive studies, were prevailing. To step up the development of research into this field, a wide variety of research methods should be utilized in the future. As for the sphere of research, the characteristics of founders, strategic characteristics and environmental characteristics were mainly covered as the success factors of venture business. More diverse variables should be explored as well to make more advanced, extended research in the years to come. The findings of the study are expected to provide both theoretical and practical information on the establishment and success of venture business to make a contribution to the development of research.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.1
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• pp.30-35
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• 2010

Purpose: Infectious ileocecitis is an infection confined to the ileocecal area and one of the most common causes of pediatric abdominal pain. This study was performed to demonstrate the clinical features of infectious ileocecitis in children. Methods: The medical records and radiologic findings of 37 patients with ileocecitis diagnosed by ultrasonography and/or computed tomography, who were admitted to Pusan National University Hospital from January 2004 and July 2008, were reviewed retrospectively. Viral gastroenteritis and secondary ileocecitis were excluded. Results: The mean age of the patients was 4.8${\pm}$3.4 years. One-half of the patients were preschool children. The chief complaint was abdominal pain (75.7%), diarrhea (10.8%), and vomiting (8.1%). Accompanying symptoms were fever (56.8%), vomiting (21.6%), and diarrhea (16.2%). The mean duration of abdominal pain, fever, diarrhea, and vomiting was 3.8${\pm}$2.1, 3.0${\pm}$1.9, 3.4${\pm}$1.9, and 2.4${\pm}$2.3 days, respectively. The frequency of diarrhea and vomiting was 5.8${\pm}$2.2 and 4.0${\pm}$2.8 per day, respectively. Diagnosis was made by abdominal ultrasonography in 22 patients (59.5%), abdominal CT in 2 patients (5.4%), and both modalities in 13 patients (35.1%). Besides the radiologic finding of thickening of the bowel wall, mesenteric lymphadenitis (59.5%), ascites (5.4%), and both mesenteric lymphadenitis and ascites (16.2%) were revealed. The mean duration of illness was 7.5${\pm}$5.0 days. There were no specific laboratory findings, and culture studies with stool or blood were negative. All of the patients recovered completely without specific treatment. Conclusion: Infectious ileocecitis has acute appendicitis-mimicking symptoms, but is self-limited within a few days, thus unnecessary treatment and work-up is avoided. However, distinguishing infectious ileocecitis from appendicitis, inflammatory bowel disease, and mesenteric lymphadenitis is important.

• The Journal of the Petrological Society of Korea
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• v.24 no.1
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• pp.25-54
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• 2015

Syenite is not a common rock, unlike granitic rocks formed the major component of the continental crust. The aim of this study is to decipher the occurrences and detailed descriptive characteristics of the syenite distributed in Sancheong area, and to investigate the petrogenesis of the syenitic magma based on geochemical study. The dominant minerals in syenite are alkali feldspar (usually orthoclase and rarely microcline), plagioclase, amphibole, biotite, and quartz. Syenites are found in a wide variety of colors. The anhedral hornblende and biotite filling the boundary of feldspar and quartz indicate that the hydrous minerals were crystallized lately, and that water was insufficient at the beginning of crystallization in magma. According to the analysis of mineral composition, amphibole in syenite is mostly ferro-edenite, and the pressure is calculated as 3.3~4.9 kb with 11.9~17.3 km of emplacement depth. Biotite and pyroxene are plotted in the region of annite and hedenbergite, respectively. Based on petrochemical studies of major elements, syenite belongs to alkaline series, metaluminous, and I-type. On the other hand, the variation patterns of trace and rare earth elements of syenite differ from the patterns of diorite and granite. In the geochemical characteristics, syenite is different from gabbro-diorite spatially adjacent to syenite, as well as granite. These results suggest that each rock has been generated from the different sources of magma. Additionally, based on the experimental data, the syenitic magma can be formed (1) by the partial melting at a high pressure and dry system, (2) when the initial crystallization minerals to be residue with migration of the residual melts separated from the ascending cotectic magma (3) when fluorine compositions to be plentiful in the protolith and/or at depth of the magma. Based on the petrographic characteristics of the syenite, Sancheong syenitic magma may have been formed by partial melting in a dry system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.563-574
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• 1986

The structure of gonads, gametogenesis and reproductive cycle of the jackknife clams, Solen strictus and Solen gordonis were investigated mainly by histological observation. The first species used were monthly sampled at the coastal area of Dadaepo, Pusan, Korea and Naechodo, Kunsan, Korea for one year from February 1982 to January 1983. The second species were monthly sampled at the sand beach of Dadaepo, Pusan, Korea, from February 1982 to January 1983. Sexualities of Solen strictus and Solen gordonis are dioecious, and these species are oviparous. The gonads are irregularly arranged from the subregion of mid-intestinal gland in visceral cavity to reticular connective tissue of foot. The ovary was composed of a number of small ovarian sacs and the testis was composed of several testicular lobuli which from the tubular structure. Early multiplicating oogonium was about $10{\mu}m$ in diamater. Nucleus and nucleolus, at that time, were distinct in appearance. Each of the early growing oocytes made an egg-stalk, connected to the germinal epithelium of the ovarian sac. A great number of undifferentiated mesenchymal tissue and eosinophilic granular cells are abundantly distributed in the ovarian sacs in the early development stages. With the further development of gonad, these tissue and cells gradually disappeared. Then the undifferentiated mesenchymal tissue and eosinophilic granular cells function as nutritive cells in the formation and development of the early stage germ cells. Mature oocytes were free in the lumen of ovarian sacs and gradually become round or oval. Ripe oocyte was about 80 to $90{\mu}m$ in diameter. With the further development of testis, each of the testicular lobuli formed stratified layers composed of spermatogonia, spermatocytes, spermatids and spermatozoa in groups on the germinal epithelium. After spawning, the gonad gradually degenerated, and disorganized completely. Then new differentiated tissues were rearranged next year. The annual reproductive cycle of those species could be classified into five stages; multiplicative, growing, mature, spent, degenerative and resting stage. It seems that the spawning season is closely related to the water temperature, and the spawning of Solen strictus occurs from June to July at above $20^{\circ}C$ in water temperature. The peak spawning season appeared in June at Dadaepo and in July at Kunsan, The spawning of Solen gordonis occurs from May to June with the peak spawning season in June. Percentages of the first maturity in female of Solen strictus ranging from 5.1-6.0 cm and 7.1-8.0 cm in shell length were $50\%$ and $100\%$, respectively.

• Journal of Life Science
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• v.17 no.11
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• pp.1576-1581
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• 2007

Dopamine reward pathway projecting from ventral tegmental area to nucleus accumbens is well known as playing an important role in alcohol dependence. It is supposed that this dopamine pathway is modulated by $5-HT_3$ nervous system, and it was reported that ondansetron (OND), $5-HT_3$ receptor antagonist, reduced drinking amount and increased abstinence rate in alcohol-dependent patients. The purpose of this study is to investigate the effect of combination of OND and naltrexone (NTX), non-specific opioid receptor antagonist, on alcohol intake in C57BL/6 mice. In 40 C57BL/6 mice in the state of alcohol dependence, vehicle, while OND 0.01 mg/kg, or NTX 1.0 mg/kg administrated respectively, or OND 0.01 mg/kg and NTX 1.0 mg/kg administrated simultaneously for ten days, medication effects on 2-hr alcohol, 22-hr water, 24-hr food intake and body weight were studied. When vehicle group was compared with 3 medication groups respectively, using a repeated measure ANOVA, NTX alone and vehicle groups showed a significant medication by time interaction (p=0.042) in 2-hr alcohol intake, but in the other 2 groups, OND and NTX combination group and OND alone group, there was no significant interaction with vehicle group in 2-hr alcohol intake. From these results, it is suggested that there is no effect on alcohol intake in mice treating with OND, and naltrexone#s suppression effect on alcohol intake in mice is attenuated when treating with OND and NTX simultaneously. It is supposed that a further study looking at the interactions of serotonin, dopamine and opioid nerves systems will be needed.