• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.282-293
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• 2020

This study investigated a long-term variation trend of water quality, fish compositions, and ecological health conditions in the Gwanpyeong stream located in the nearby Daejeon metropolitan city to understand the impact of urban development projects on the aquatic ecosystem. The sampling was made in four surveys (2009, 2010, 2016, 2019) before and after urbanization. The urban development was conducted in 2008, resulting in the stream's ecological disturbance, and the stream restoration was conducted in 2012. Thus, stream monitoring was conducted to analyze the ecological trends before and after the restoration. The multi-metric models for Fish Assessment Index(FAI) and necropsy-based Health Assessment Index(HAI) were applied in the fish community and organ-level, respectively, to assess the ecological health of the stream. Minimum turbidity and chlorophyll-a(Chl-a) occurred in the mid-stream(St. 2), and this was probably due to rapid current velocity in the riffle zone. We collected 18 fish species, and the dominant species was Zacco platypus (40.6%). In 2016 immediately after the stream restoration, the relative proportions of sensitive species and insectivore species were the highest along with highest values in the species diversity and species richness index, resulting in the best condition in the ecological health, based on FAI model values. However, the ecological health, based on the FAI, became worse in the latest survey conducted in 2019. The analysis of the HAI model based on the organ-level approach showed skin erosion in the fish of upper stream, kidney defects in downstream, and the liver and gill defects observed in all sites, indicating that the anatomical health was also affected.

• Journal of Korean Public Health Nursing
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• v.3 no.1
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• pp.18-37
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• 1989

This study was done in order to analyze the factors which influenced the performance level of community health practitioners' task. Interview survey was done during the period from August to October, 1986. Interviewee were 166 CHPs among total of 217 CHPs in Kyonggi province area. Multiple stepwise regression and canonical correlation analysis were used to identify major factors influenced to perform community health practitioners' task. The results of this study were summarized as follows: 1. General characteristics of CHPs 1) Personal characteristics The average age of CHPs was 37.8 years and their marital status was $77.6\%$ of married, educational back-ground was $65.3\%$ of junior college graduation. Their job career was $38.6\%$ of between 1-3 years, $33.3\%$ of between 3-5 years, $22.2\%$ of less than 1 years. Most of CHPs$(62.8\%)$ were fully satisfied with their job, $33.3\%$ were moderately, and $3.8\%$ were not satisfied. 2) Working environmental condition Only $31.7%$ of CHPs were satisfied with their working condition of primary health post, $26.6\%$ were not satisfied. Half of CHPs$(52.5\%)$ replied having good cooperation with health center, $10.1\%$ replied bad. Cooperation with health subcenter was good in $32.9\%$, and bad in $21.9%$. Cooperation with private health institutions was good in $34.2\%$, bad in $21.6%$. 2. Performance level of community health practitioners' task Among a total of 52 contents of their functions medical history taking. physical examination, referral of diagnostic laboratory work-up($(86.4\%)$, health assessment of pregnant women$(82.1\%)$, development of health information system$(79.4\%)$, supervision of health workers $(78.4\%)$, follow-up of family planning acceptors$(77.3\%)$, and follow-up of family planning acceptors' side effects$(77.3\%)$ were actively performed. Diagnosis of pregnancy$(62.1\%)$, sampling of drinking water for quality test$(52.5\%)$, making list of equipment' & supplies $(51.5\%)$, evaluation of primary health post activities $(37.6\%)$, organization of village health workers$(32.4\%)$ and management of village health workers $(30.1\%)$ were poorly performed. 3. Stepwise multiple regression analysis of job function The factors which influenced the performance level of community health practitioners' function were age, marital status, educational level, job career, job satisfaction, satisfaction of working environment of primary health post, cooperation of health center, cooperation of health center, cooperation of private health instiutions in orders. These 9 variables were able to explain job function from $25.7\%$ of program planning to $6.7\%$ of management of common disease. 4. Canonical correlation analysis between the performance of function and general characteristics of CHPs. Cooperation of private health institutions was found to be the factor influencing task performance of community organization, management of primary health post, technical supervision of health personnels. Job satisfaction of CHPs was also found to be the factor influencing task performance of family planning, management of common disease and maintenance of health information system.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.165-196
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• 2008

This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.83-90
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• 2010

This study was conducted to investigate the residue amount of harmful materials on the 153 commercial medical herbs in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD, LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 7 samples, and were over MRLs (Maximum Risk Levels) in 2 samples (1.3%). The mean values of heavy metal contents (mg/kg) were Pb, 0.570; Cd, 0.081; As, 0.082; Hg, 0.0093. The measured values of Pb, As, Hg showed within MRLs. The excess samples of MRLs were 3 samples (changchul 2, cheongung 1) on Cd. The sulfur dioxides were over MRLs in 7 samples (4.6%), hwanggi and gugija. These results will be used to establish on the regulation of commercial medical herbs in Gwangju area.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.1
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• pp.77-94
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• 2012

The purpose of this study is to analyze the process of vertical fragmentation of regional industries in Korea using Revealed Comparative Advantage index (RCA) and Average Propagation Length (APL). First of all, the competitiveness in regional export and substitution of regional imports were strong in the Electricity, Gas, and Water supply sector in Gyeongnam, and consumer-oriented Manufacturing sector in Incheon, Gyeongnam, and Gwangju. The high values of the APL were also found in the regions with common similarity with respect to the industrial structure and the sectors with indirect effects. In addition, the industrial sectors with high quality of infrastructure, and endowed services tended to be located in the beginning of the production chain. FInally, since manufacturing and service sectors in Seoul has higher APL, they could lead the growth of other related industries as key sectors, in the production fragmentation.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.452-460
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• 2000

This study was to investigate the growth characteristics, physiological adaptation of Pinus densiflora(Japanese Red Pine) seedlings at the artificial canopy gap in the Quercus acutissima plantation and to analyze its natural regeneration mechanism. Photosynthetic and transpiration rates were analyzed by different levels of photosynthetically active radiation and by seedling growth. Comparing to seedlings at the open area, those at the canopy gap showed more growth in height than in diameter with different levels of light quality and low light intensity, and the increase rate of dry weight was higher in the aboveground than in the underground, maintaining relatively high T/R rate. The C/F(the ratio of non-photosynthetic organs to photosynthetic organs in dry weight) of the aboveground at the canopy gap was higher than that at the open area by 0.1~0.2, while light saturation and light compensation points at the canopy gap were lower than that at the open area by $300{\mu}mol\;m^{-2}s^{-1}$ and 40%, respectively. The seedlings appeared to have shade tolerance to a certain extent at the young growth stage despite Pinus densiflora is typically classified shade-intolerant species. With light intensity lower than $400{\sim}450{\mu}mol\;m^{-2}s^{-1}$, photosynthetic rate and water use efficiency relatively increased by effective use of light energy.

• Fire Science and Engineering
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• v.34 no.3
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• pp.43-48
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• 2020

The purpose of this study is to develop an earth leakage alarm circuit breaker, equipped with a leakage alarming function (JER-E2S, ETECKOREA Co., Korea), and to analyze its characteristics. The developed mechanism is exclusively used for single-phase and 220 V circuits, with a rated current of 32 A, 20 A, 20 A (for restrooms), 16 A, etc. It satisfies all characteristics of existing earth leakage circuit breakers (ELB). If a fire current, which is a resistive leakage current (Igr), flows through an electric line, the device detects the leakage current in real time and warns against the leakage through a blinking LED lamp. Since the developed device displays a tolerance to a capacitative leakage current (Igc) that inevitably occurs in LED lamps, communication devices, etc., it ensures a stable power supply. In addition, the earth leakage alarm circuit breaker protects against power failure due to a momentary ground fault. Therefore, it can supply power without the risk of the circuit breaker malfunctioning due to a momentary ground fault caused by water droplets, leaves, etc. Moreover, with a standby power of less than 0.1 W, the developed earth leakage alarm circuit breaker exhibits a power saving performance that is 3~8 times greater than that of other ELBs. Installation of approximately 10 earth leakage alarm circuit breakers in one apartment household, with an area of 120 ㎡, can save 2~5 kWh per month. Therefore, the developed earth leakage alarm breaker not only satisfies the characteristics of existing earth leakage breakers, but also exhibits outstanding power supply quality since it has the functions of electric fire prevention and malfunction prevention. Therefore, this device can innovatively contribute to electric fire prevention.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.172-182
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• 2009

This study was to analyze characteristics based on tolerance and trophic guilds and to determine the level of total mercury in tissues of sentinel species, Zacco platypus at 3 sampling sites of the Mangyeong River in 2007. Total sampled fishes were 26 species and the most dominant species was Zacco temminckii (47%). Fish community analysis was resulted that eveness index and diversity index showed low value at S1. However, diversity index and richness index at other sites showed high. According to various guilds analysis, relative abundance of sensitive species was 70% and 42% at S1 and S2, respectively. While sensitive species were decreased (1%) and tolerant species were increased (60%) at S3. It was mainly carried to the impacts of wastewater treatment plants near the location. Relative abundance of insectivore species was decreased from up (S1) to midstream area (S3). In addition, chemical water quality, based on analyses of BOD, COD, TP, TN, EC, MPN and SS concentration showed similar trends. Qualitative Habitat Evaluation Index (QHEI) was averaged 164, judged as "good" habitat condition. Average concentrations of total [Hg] was 146.9 ${\mu}g$ $kg^{-1}$. In the muscles of total [Hg] was the highest, and then followed by kidney, vertebrae, liver, and gills. According to FDA standards (500 ${\mu}g$ $kg^{-1}$) of Korea, total [Hg] has not affected to the individual fish health.

• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1193-1202
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• 2018

It is important to quantitatively analyze the energy budget for understanding of long-term climate change in Arctic. High-quality and long-term radiative parameters are needed to understand the energy budget. Since most of radiative flux components based on satellite are provide for a short period, several data must be used together. It is important to acquaint differences between data to link for conjunction with several data. In this study, we investigated the comparative analysis of Arctic radiative flux product such as CERES and GEWEX to provide basic information for data linkage and analysis of changes in Arctic climate. As a result, GEWEX was underestimated the radiative variables, and it difference between the two data was about $3{\sim}25W/m^2$. In addition, the difference in high-latitude and sea ice regions have increased. In case of comparing with monthly means, the other variables except for longwave downward flux represent high difference of $9.26{\sim}26.71W/m^2$ in spring-summer season. The results of this study can be used standard data for blending and selecting GEWEX and CERES radiative flux data due to recognition of characteristics according to ice-ocean area, season, and regions.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.1
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• pp.57-63
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• 2019

This study was conducted to find out the effect that ${\kappa}-Carrageenan$ has on the properties of dog sperm when it was added to the cryoprotectant. Extender basically was contained 1.21 g Trizma base, 0.67 g citric acid, 0.4 g glucose, 0.03 g penicillin G, 0.05 g streptomycin sulfate. Extender1 was added with 0.1%, 0.2%, 0.3%, and 0.5% carrageenan, while extender2 was supplemented with glycerol. After freezing-thawing, the motility, viability, acrosome integrity, apoptosis, and ROS (reactive oxygen specifications) of sperm were measured to analyze the effects of the supplementation of carrageenan. Total Motile (TM), Rapid Progressive Motile (RPM), Medium Progressive Motile (MPM), and Immotile were measured through the CASA system after thawing in 37 degree water. Extender with 0.2% ${\kappa}-carrageenan$ ($64.26{\pm}0.49$) was significantly higher than control ($40.24{\pm}8.27$) (p < 0.05). RPMs of extender with 0.1%, 0.2% ${\kappa}-carrageenan$ ($57.64{\pm}6.34$, $56.47{\pm}1.35$) were significantly higher than the other groups (p < 0.05). Acrosome integrity was measured by dyeing to PSA-FITC with an epifluorescence microscope. Normal acrosome ratio of extender with 0.5% ${\kappa}-carrageenan$ ($61{\pm}8.03$) was higher than the other groups (p < 0.05). Apoptosis was measured with a FACSCalibur flow cytometer using FITC (FITC Annexin V Apoptosis Detection Kit). Treated groups of ${\kappa}-carrageenan$ of 0.1% ($0.81{\pm}0.05$), 0.2% ($0.85{\pm}0.05$) were significantly higer (p < 0.05) than control. Modified SYBR/PI staining was used for determination of viability and DCF staining was used for evaluation of ROS. Viability and ROS were not significantly different from other groups. In conclusion, adding a certain concentration of carrageenan to the extender of cryopreservation, carrageenan contributes to the improvement of the sperm motility, acrosome integrity and prevention of apoptosis.