• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.447-454
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• 2014

Organic solar cells (OSCs) have intensively studied in recent years due to their advantages such as cost effectiveness and possibility of applications in flexible devices. In spite of the high power conversion efficiency (PCE) of 10 %, the OSCs still have a draw back of their low environmental stability due to the oxidization of aluminum cathode and etching of transparent conducting oxide as electrode. To solve these problems, the inverted structured OSCs (I-OSCs) having greatest potential for achieving an improvement of device performances are suggested. Therefore, there are a lot of studies to develope of interface layer based on organic/inorganic materials for the electron transport layer (ETL) and passivation layer, significant advancements in I-OSCs have driven the development of interface functional materials including electron transport layer. Recent efforts to employing 2D/3D zinc oxide (ZnO) based ETL into I-OSCs have produced OSCs with a power conversion efficiency level that matches the efficiency of ~9 %. In this review, the technical issues and recent progress of ZnO based ETL in I-OSCs to enhancement of device efficiency and stability in terms of materials, process and characterization have summarized.

• Korea Journal of Hospital Management
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• v.8 no.3
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• pp.72-91
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• 2003

The purpose of this study is to investigate the recognition of health information managers, and to analyze the level of job satisfaction and organizational commitment of medical record technicians. The data for this study were collected through a self-administered survey with a structured questionnaire to 172 subjects from medical record technicians working in hospitals in Seoul and Gyeonggi Province as well as the faculty of medical schools across South Korea. In this analysis frequency, t-test, ANOVA, factor analysis and structural equation model were used. The main findings of this study are as follows: 1. As for recognition of the seven dimensions in the role of health information managers, the role as clinical data specialist received the most positive feedback, followed by document & repository managers, patient information coordinators, health information managers, data quality managers, security officers and research & decision support analyst. 2. The level of job satisfaction among medical information handlers and managers averaged 3.14. In terms of the factors in the work environment concerned with job satisfaction, being able to work independently and as team players reached the top among 6 factors with the average of 3.39, followed by professional position, salary & rewards, expectations for job performance and administration. 3. The average rate of organizational commitment stood at 3.09. Respondents tend to be focused on present tasks rather than future-oriented tasks. 4. The result of the analysis based on the relationship between recognition as health information managers, job satisfaction and organizational commitment found that all analysis are statistically meaningful. The more the respondents were aware of their roles as health information managers, the more they tended to be committed to their work and satisfied with their work. The more the respondents were committed to their work, the more satisfaction was seen. The effects of recognition as health information managers on organizational commitment measured 0.27 and for job satisfaction it was 0.17. The effects of organizational commitment on job satisfaction stood at 0.71. The feasibility of the model meets the standard at Chi-square value of 66.755 and the P value of 0.057. The Normed Fit Index (NFI) of 0.930 was in compliance with the standard for model feasibility and the squared multiple correlation coefficient of this model was 8% in organizational commitment and 60% in job satisfaction.

• Food Science and Preservation
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• v.16 no.6
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• pp.985-990
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• 2009

Fatty acid composition, protein content, and shape change of Listeria monocytogenes treated with ethanol extracts from Schizandra chinensis were examined. Transmission electron micrography of cells treated with ethanolic S. chinensis extracts showed development of morphological changes. Cell surfaces were irregular, swollen, or even disrupted after treatment with ethanol extracts, compared with the smooth surfaces of normal cells. Interestingly, cell protein content was decreased by ethanol extract treatment. Cell fatty acid composition was also changed after treatment with ethanol extracts. The levels of 13-methylpentadecanoic acid (i-15:0), 12-methylpentadecanoic acid (a-15:0) and 15-methylpentadecanoic acid (i-17:0) of L. monocytogenes Scott A and L. monocytogenes ATCC 19111 were decreased, but the concentrations of Cis-9,12 octadecanoic acid ($18:2^{9,12}$) and cis-9-octadecanoic acid ($18:1^9$) were increased. 13-methylpentadecanoic acid (i-15:0) and 12-methylpentadecanoic acid (a-15:0) levels in L. monocytogenes Brie I were decreased but the concentrations of Cis-9,12 octadecanoic acid ($18:2^{9,12}$) and cis-9-octadecanoic acid ($18:1^9$) were increased after treatment with ethanolic extracts. Notably, the levels of 12-methylpentadecanoic acid (a-15:0) significantly were decreased but those of cis-9,12 octadecanoic acid ($18:2^{9,12}$) significantly were increased in all tested microorganisms.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.360-369
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• 2012

Parent material, climate, topography, biological factors, and time are considered five soil forming factors. This study was conducted to elucidate the effects of several environment factors on soil distribution using quantitative analysis method, called soil series estimation algorithm in the soils of Jeju Island. We selected environment factors including mean temperature, annual precipitation, surface geology, altitude, slope, aspect, altitude difference within 1 $km^2$ area, topographic wetness index, distance from the shore, distance from the mountain peak, and landuse for a quantitative analysis. We analyzed the ranges of environment factors for each soil series and calculated probabilities of possible-soil series for certain locations using estimation algorithm. The algorithm can predicted exact soil series on the soil map with correctness of 33% on $1^{st}$ ranking, 62% within $2^{nd}$ ranking, 74% within $5^{th}$ ranking after estimating using randomly extracted environment factors. In predicted soil map, soil sequences of Entisols-Alfisols-Andisols on northern area and Alfisols-Ultisols-Andisols on western area can be suggested along increasing altitude. More modeling studies will be needed for the genesis process of soils in Jeju Island.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.171-177
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• 2013

The aim of the present study was to determine the evidence of post-parturient disorders and backfat loss during lactation in sows raised in tropical areas in relation to their backfat thickness before farrowing and postpartum intravenous supportive treatment. Backfat thickness was measured using A-mode ultrasonography at farrowing and weaning ($25.5{\pm}1.4$ d) in 70 sows. The sows were divided into three groups according to backfat thickness before farrowing, i.e., 15.0 to 20.0 mm (n = 21), 20.5 to 25.0 mm (n = 35), >25.0 mm (n = 14) and were categorized into two groups according to the postpartum supportive treatment, i.e., control (n = 31) and treatment (n = 39). After farrowing, the sows in treatment group received the same medications as in control sows. Furthermore an intravenous supportive treatment with amino acids and vitamins was administered in treatment groups. Rectal temperature and clinical signs of the sows including vaginal discharge, udder problems and appetite were determined at d 0, 1, 2 and 3 of parturition. It was found that, on average, the backfat thickness was $22.4{\pm}3.9$ mm at farrowing and $19.9{\pm}2.9$ mm at weaning. The backfat loss and the relative backfat loss during the lactation period were 2.6 mm and 10.6%, respectively. The sows with a backfat of 15.0 to 20.0 mm before farrowing lost less backfat than those with a backfat of 20.5 to 25.0 mm and >25.0 mm (p<0.05). Sows with a backfat of 15.0 to 20.0 mm had a better appetite on d 1 postpartum than sows with a backfat of 20.5 to 25.0 mm (p = 0.020). The percentage of sows losing backfat >10% during lactation were higher in sows with a backfat of >25.0 mm before farrowing (85.7%) than sows with a backfat of 15.0 to 20.0 mm before farrowing (35.0%) (p = 0.008). The percentage of sows with a reduced appetite on d 1 (90.3% vs 71.8%, p = 0.018) and d 2 (61.3% versus 33.3%, p = 0.005) postpartum in the treatment group was lower than the control group. In conclusion, the backfat thickness of sows at farrowing influenced backfat loss during lactation under hot and humid climates. The intravenous supportive treatment of sows with amino acid and vitamins significantly improved the appetite of postpartum sows.

• Asian Journal of Atmospheric Environment
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• v.7 no.2
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• pp.120-128
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• 2013

The concentration and composition of particulate matter (PM) in the atmosphere can directly reflect the environmental pollution. The atmospheric pollution in some Cameroonian cities is increasing with the industrial development and urbanization. Air pollution is inherently complex, containing PM of varied size and composition. This PM exists as a dynamic cloud interacting with sunlight and is modified by the meteorology. The reflectometer and the EDXRF spectrometry are applied to determine the concentration of some specific elements at four sites in the city of Yaound$\acute{e}$. The particular aim of the present work is to put in place data base on air pollution in urban area and elaborate regulations on the emissions issued to industrial and vehicle activities. This study provides an overview of the concentration of black carbon and some specific elements in the air, which have impacts on human health. The measurement was done by distinguishing the size of particle. So that, the particle with aerodynamic diameter between $2.5-10{\mu}m$ (so-called coarse particle) and aerodynamic diameter < $2.5{\mu}m$ (so-called fine particle) were considered to obtain more information about levels of the inhalable fraction of the location. The results obtained in four locations of the city of Yaound$\acute{e}$ show that the black carbon concentration is very considerable, the element sulfur is a major pollutant and the concentration of fine particle is very greater. The results obtained of fine and coarse filters range from $5-17{\mu}g/m^3$ and $10-18{\mu}g/m^3$ for the black carbon. S, Cu, Zn, Pb, Cd, As, Se and Hg are the specific findings of this work. The pollutants with a greater concentration are S, Pb, and Zn. These later seem to be non-uniformly, non-regular in some location and high compared to other countries. This work allows us to make a potential relation between pollutants and emission sources. In this framework, some suggestions have been proposed to reduce emissions for an improvement of the air quality in the environment and thus, the one of the city of Yaound$\acute{e}$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.155-163
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• 2013

The ancient sailing routes between Silla Korea and Tang China have been a hot issue among the researchers. Some assert that the Korean seafarers under Chang Po-go sailed the East China Sea directly from China to the Korean Peninsula with the assistance of mariner's compass on boarding V-shaped vessels in the 9th century. As we all know, Chinese used the mariner's compass in the 11th century and Europeans in the 12th century. In this paper, the author analyzed the maritime meteorological condition for sailing ships to navigate in the East China Sea and retraced the rafting route by Yun in 1997. As the results of analysis, the author confirmed that the maritime meteorological condition might be favorable for the seafarers to be capable of navigating in the East China Sea from China to Korea in June and July. But even the sea condition might be favorable, it must be God's will for the ancient seafarers to reach the Korean Peninsula. On Yun's rafting account, the author found out that there is a difference between the sailing route drawn by Yun himself and the actual drifted route and the raft drifted at 1.7~2.0 knots. This was quite an extraordinary speed considering the unfavorable sea condition and raft itself without keel. In conclusion, the author reaffirms that it was after the year 1068 for the seafarers to navigate in the East China Sea directly from China to Korea without any historical proofs or evidences.

• Reproductive and Developmental Biology
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• v.37 no.3
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• pp.135-141
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• 2013

This study aimed to improve the reproductive efficiency of dairy herds by comparison and analyzing estrous appearance rate, conception and non-conception rate according to the stage of lactation using the lactation and reproductive records of average (less than 10,000 liters milk in 305 days) and high yielding (more than 10,000 liters milk in 305 days) Holstein cows (n=102). Milk production and reproduction data were collected between January 2010 and December 2012 from Holstein cows kept in the commercial dairy farms. Average (n=32) and high yielding (n=24) Holstein cows used to analyze the relationship between milk yield and reproductive performance. Our results showed that estrous appearance rate according to the stage of lactation was 25.0% (30~59d), 40.6% (60~89d), 25% (90~110d) and 9.4% (>111d) in average yielding cows and 16.7% (30~59d), 20.8% (60~89d), 12.5% (90~110d) and 50.0% (>111d) in high yielding cows, respectively. Conception rate according to the stage of lactation was 87.5% (30~59d), 61.5% (60~89d), 75.0% (90~110d) and 66.7% (>111d) in average yielding cows and 25.0% (30~59d), 0% (60~89d), 33.3% (90~110d) and 50.0% (>111d) in high yielding cows, respectively. Days between parturition and conception was 23.7% (<149d), 0% (150~209d) and 0% (>210 d) in average yielding cows and 69.0% (<149 d), 77.8% (150~209d) and 38.9% (>210d) in high yielding cows, respectively. Conception rate from 110 days postpartum in high yielding cows was 41.7% (110~150d), 50.0% (151~180d) and 50.0% (>181d). Body condition score (BCS) in 120 days postpartum was $2.64{\pm}0.1$ in average yielding cows and $2.28{\pm}0.1$ in high yielding cows, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.4
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• pp.315-326
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• 2015

Temporal and spatial variations of surface water temperature in Jinju Bay for the period of 2010~2011 were studied using the data from temperature monitoring buoys deployed at 17 stations in the south coast of Korea. Water temperature shows the maximum late in January and the minimum early in August. Seasonal variation of water temperatures at the north part of the bay is smaller than the middle and the south. In summer, the lowest and the highest of maximum water temperature are distributed around Jijok Channel which is located at the south of the bay. The fluctuations of water temperatures at Noryang and Daebang Channel are smaller than others because of vertical mixing caused by passage of strong tidal currents. Wind and strong currents affect on the stratification of the surface water layer near Daebang Channel. High temperatures come in frequently around the north area when eastward constant flows appear at neap tide as blowing westerly in the springtime at Noryang Channel. Spectral analyses of temperature records show significant peaks at 7~20 day periods at Noryang Channel, 7~20 day and semidiurnal at the west coast of Changsun Island and Jijok Channel and 7~20 day and diurnal at the middle of the bay. Temperature fluctuation at Noryang Channel shows high coherence and has leading phase with those at other stations in the bay. However, the phase of temperature fluctuation at Noryang Channel falls behind that at Daebang Channel. Daebang Channel has an influence on the temperature fluctuation only at the west and middle part of the bay. Cross-correlation analyses for the temperature fluctuation show that Jinju Bay could be classified into six areas; Noryang Channel, the area of convergence and divergence at the north, Daebang Channel, the west coast of Changsun Island, the mixing area at the middle of the bay and the south inside of the bay, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5206-5210
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• 2012

We studied the effect of food concentration on grazing, growth and fecundity of cyclopoid copepod Paracyclopina nana. Marine phytoplankton Tetraselmis suecica was used as a livefood for the copepod. Six stage compositions were used and food concentrations for the experiment were 0.5, 1, 2, 5, 10, 20, 40, 60 and $80{\times}10^4$ cells/mL. Range of food concentrations with 0.2, 0.5, 1, 2, 3 and $4{\times}10^4$ cells/mL were used for nauplii production experiment. Grazing rates of P. nana in all developmental stages on the different concentrations were increased with increasing diet concentration. While the growth of nauplius was not affected by increase of food concentration, food concentration outside of $1{\times}10^4$ to $5{\times}10^4$ cells/mL range negatively affected that of copepodite. Daily nauplii production was increased with increasing food concentration but $3{\times}10^4$ and $4{\times}10^4$ cells/mL treatments were not significantly different with $2{\times}10^4$ cells/mL treatment. As a result, optimum concentration of T. suecica for mass culture of P. nana was considered to be 5,000 cells/mL for nauplius stage, 10,000 cells/mL for copepodite stage and adult male, 20,000 cells/mL for adult female, respectively.