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Assessment of Pollutant Loads for Water Enhancement in the Mankyeong River (만경강 유역 오염부하량 평가)

  • Lee, Kyeong-Bo;Kim, Jong-Cheon;Kim, Jong-Gu;Lee, Deog-Bae;Park, Chan-Won;Kim, Jae-Duk
    • Korean Journal of Environmental Agriculture
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    • v.24 no.2
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    • pp.83-90
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    • 2005
  • This study was conducted to evaluate the influence of pollutant loads on the water quality in the Mankyeong River from January 2002 to December 2004. The BOD level in upstream ranged from 0.58 to 1.57 mg $L^{-1}$, which would be in I grade according to water quality criteria by Ministry of Environment but BOD level in midstream and downstream was III grade. T-N contents were high in midstream and the average T-P level ranged from 0.06 to 2.70 mg $L^{-1}$. The point raw loads of BOD was high in Iksancheon, Mokcheonpo and Cheongha basin. The point raw loads of T-N and T-P were high in Iksancheon and Cheongha watershed. The non-point low loads of BOD were 3,931 kg $day^{-1}$, 2,870 kg $day^{-1}$ and 2,827 kg $day^{-1}$ in Mokcheonpo, Top and Jeonju watershed, respectively. The major source of BOD effluent load was population, that of T-N and T-P effluent loads was livestock. The delivered load of T-N were high in Jeonju, Mokcheonpo, Gosan, Iksancheon watershed in order. The delivered load of T-N was high in Jeonju watershed and that of T-P was high in Jeonju and Iksancheon watershed. The delivery ratio of BOD and T-N at dry season were below 100% except Mokcheonpo watershed. The delivery ratio of BOD and T-N at raining season were high in Gosan watershed.

Assessment of Pollutant Loads in the Dongjin River (동진강 유역의 오염부하량 평가)

  • Lee, Kyeong-Bo;Kim, Jong-Cheon;Kim, Jong-Gu;Lee, Deog-Bae;Park, Chan-Won;Kim, Jae-Duk
    • Korean Journal of Environmental Agriculture
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    • v.24 no.2
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    • pp.91-97
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    • 2005
  • This study was conducted to evaluate the influence of pollutant loads on the water quality in the Dongjin River area from January 2003 to December 2004. The average value of BOD and T-N showed the highest peak in Yongho, Dukcheon watershed among Dongjin River. Concentrations of BOD, T-N and T-P in Jeongeup watershed were 2.29 mg $L^{-1}$, 4.40 mg $L^{-1}$ and 0.27 mg $L^{-1}$, respectively. Concentration of BOD in Chilbo was 1.19 mg $L^{-1}$ which would be in the grade I according to water quality criteria by Ministry of Environment. The BOD level in Wonpeung and Sinpeung watershed ranged from 4.06 to 7.35 mg $L^{-1}$. The T-N effluent loads of non-point pollutants were high in Wonpeung, Gobu, Yongho Dukcheon, Jeongeup and Sinpeung watershed in order. The major sources of BOD, T-N and T-P effluent loads were Livestock. The T-P effluent load of non-point pollutant was 68 kg $day^{-1}$ in Wonpeung, 58 kg $day^{-1}$ in Yongho Dukcheon and 45 kg $day^{-1}$ Jeongeup watershed. The delivered loads of BOD was high in Gobucheon, while both T-N and T-P were high in Yongho Dukcheon. The delivery ratio of BOD and T-N at dry season was below 100% in all watershed of Dongjin River. The delivery ratio of T-N at raining season was high in Yongho Dukcheon and Chilbo watershed

Numerical Simulation of Residual Currents and tow Salinity Dispersions by Changjiang Discharge in the Yellow Sea and the East China Sea (황해 및 동중국해에서 양쯔강의 담수유입량 변동에 따른 잔차류 및 저염분 확산 수치모의)

  • Lee, Dae-In;Kim, Jong-Kyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.2
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    • pp.67-85
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    • 2007
  • A three-dimensional hydrodynamic model with the fine grid is applied to simulate the barotropic tides, tidal currents, residual currents and salinity dispersions in the Yellow Sea and the East China Sea. Data inputs include seasonal hydrography, mean wind and river input, and oceanic tides. Computed tidal distributions of four major tides($M_2,\;S_2,\;K_1$ and $O_1$) are presented and results are in good agreement with the observations in the domain. The model reproduces well the tidal charts. The tidal residual current is relatively strong around west coast of Korea including the Cheju Island and southern coast of China. The current by $M_2$ has a maximum speed of 10 cm/s in the vicinity of Cheju Island with a anti-clockwise circulation in the Yellow Sea. General tendency of the current, however, is to flow eastward in the South Sea. Surface residual current simulated with $M_2$ and with $M_2+S_2+K_1+O_1$ tidal forcing shows slightly different patterns in the East China Sea. The model shows that the southerly wind reduces the southward current created by freshwater discharge. In summer during high runoff(mean discharge about $50,000\;m^3/s$ of Yangtze), low salinity plume-like structure(with S < 30.0 psu) extending some 160 km toward the northeast and Changjiang Diluted Water(CDW), below salinity 26 psu, was found within about 95 km. The offshore dispersion of the Changjiang outflow water is enhanced by the prevailing southerly wind. It is estimated that the inertia of the river discharge cannot exclusively reach the around sea of Cheju Island. It is noted that spatial and temporal distribution of salinity and the other materials are controlled by mixture of Changjiang discharge, prevailing wind, advection by flowing warm current and tidal current.

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Analysis on the actual state and plan for improvement for vocational courses are operated consignment in General high school (일반고등학교 직업과정 위탁 운영의 실태 분석 및 개선 방안)

  • Yoon, Kyoung-Suk;Yi, Sang-Bong
    • 대한공업교육학회지
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    • v.36 no.2
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    • pp.131-150
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    • 2011
  • The purpose of this study vocational courses in general high schools in each city in order to operate efficiently. Provinces operating status and the general high school vocational courses through the regular high school vocational courses siltae analysis to identify operational problems, and that is to derive ways to improve. Operating in the desired direction, the typical high school vocational courses ilbango select students that meet the purpose of operating as one that students admit you need the correct promotion and career guidance and vocational courses ilbango teachers of vocational courses is operating correctly recognize the purpose and students with career guidance and vocational courses so that you can operate effectively at: Provincial Office-wide need to conduct a systematic study. Vocational courses also target students ilbango sosokgyo (wonjeokgyo) to be completed in the course stated in the plan for the school and the need to practice, and professional students ilbango by configuring a separate class is most preferable to operate. If the person is prime target, with each region run by creating a class needs to definitely consider. Entrusted to the agency's key performance improvements in order to improve the employment rate in the direction of promotional materials for the students selected to take advantage of college enrollment than the employment data for the students and their parents ilbango vocational courses for the purpose and intent is necessary to provide accurate information In addition, the employment rate is relatively low industrial (information) to install the school department employment, and employment representatives (industry-academia co-coordinator), and by placing career paths and industries to ensure the needs of industry, including working conditions and students who wish adjusting to the role, and industrial college (2 years), industrial (information) through the school's agreement to the aggressive promotional schemes seonchwieop hujinhak. Getting the need to encourage. Vocational courses ilbango in the new and the abolition, rather than the case of some popular course when you are away from work and there, so if the course-changing industry, new or repealed to reflect the demands of social work and careful review of how to connect carefully to decide by. Commissioned a systematic quality management in education, in terms of industry (information) schools and public vocational training institutions or private vocational school is better than school. However, 16 cities across the country. Also only five of the major cities around the school has industry information. Ilbango vocational courses at the expected continued demand. Degrees, the operation in terms of comparative advantage in many ways the school's new industry information is necessary to consider.

The Effects of Mean Grain Size and Organic Matter Contents in Sediments on the Nutrients and Heavy Metals Concentrations (퇴적물 내 입도와 유기물 함량이 영양염류 및 중금속 농도에 미치는 영향)

  • Kim, Seog-Ku;Lee, Mi-Kyung;Ahn, Jae-Hwan;Kang, Sung-Won;Jeon, Sang-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.9
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    • pp.923-931
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    • 2005
  • A study was carried out to identify the major causes of sediments pollution in the Paldang Lake in the vicinity of Gyeongan river. Samples from 40 sites were collected and analyzed to characterize the regional distributions of grain size, organic matter contents, and concentrations of T-N, T-P and heavy metals. contaminations. The mean grain size(Mz) ranged from sand type(Mz, $1{\sim}3\;{\phi}$) where Bukhan River and Namhan River converges at a high flow rate to silt type(Mz, $5{\sim}10\;{\phi}$) at the downstream of Gyeongancheon and Paldang lake, reflecting the water circulation in the area. Except sampling point St. 36 near the wetland, the determination coefficient($r^2$) of Mz and organic matter(LOI) was 0.88, showing that more organic matters are concentrated inside finer sediments. The concentrations of T-N and T-P in sediments were higher in the area at which Mz and organic matters are also higher. High concentrations of T-P analyzed in the sediments, ranging from $216{\sim}1,623\;{\mu}g/g$ (Avg. $769\;{\mu}g/g$) could be considered as a critical level. Adsorbed-P and NAI-P, which are easily released to the surrounding environments when physico-chemical characteristics of sediments are changed, was found to be around 20%, which was showed by the result of fractionated-P. Moreover, Principle Component Analysis(PCA), showed that high concentrations of T-N, T-P, organophilic metals (Cd, Cu, Pb, Zn) are distributed in the areas where high organic matter contents and fine grain-sized sediments are found. However, results of $I'_{geo}$ (Geoaccumulation Index) that considers the grain size of sediments showed that heavy metal concentrations in the lake was low enough to be considered as Class 1 indicating the relative degree of pollution was less than zero.

Biodiversity Conservation and the Yellow Sea Large Marine Ecosystem Project (생물다양성 보전과 황해 광역 해양생태계 관리계획)

  • Walton, Mark
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.4
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    • pp.335-340
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    • 2010
  • The paper describes the objectives of Yellow Sea Large Marine Ecosystem (YSLME) project, focusing on procedural and practical aspects. YSLME is a highly productive sea yet possibly one of the most impacted large marine ecosystems, in terms of anthropogenic stressors, due the enormous coastal population. The aim of the YSLME project is the reduction of ecosystem stress through identification of the environmental problems in the Transboundary Diagnostic Analysis (TDA) that are then addressed in the Strategic Action Programme (SAP). One of the major problems found to be affecting biological diversity is habitat modification through wetland reclamation, conversion and degradation. Since the early 1900's more than 40% of intertidal wetlands have been reclaimed in Korea, and 60% of Chinese coastal wetlands have been converted or reclaimed. Damaging fishing practices, pollution and coastal eutrophication have further degraded the coastal environment reducing the biological diversity. To combat this loss, the YSLME project has mounted a public awareness campaign to raise environmental consciousness targeted at all different levels of society, from politicians at parliamentary workshops, local government officer training events, scientific conferences and involvement of scientists in the project research and reporting, to university and high school students in our visiting internship programmes and environmental camps. We have also built networks through the Yellow Sea Partnership and by liaising and working with other environmental organizations and NGOs. NGO's are recognised as important partners in the environmental conservation as they already have extensive local networks that can be lacking in international organisations. Effective links have been built with many of these NGOs through the small grants programme. Working with WWF's YSESP project and other academic and research institutions we have conducted our own biodiversity assessments that have contributed to the science-based development of the SAP for the YSLME. Our regional targets for biodiversity outlined in the SAP include: Improvements in the densities, distributions and genetic diversity of current populations of all living organisms including endangered and endemic species; Maintenance of habitats according to standards and regulations of 2007; and a reduction in the risk of introduced species. Endorsement of the SAP and its successful implementation, during the proposed second phase of the YSLEM project, will ensure that biological diversity is here to benefit future generations.

Growth Efficiency, Carcass Quality Characteristics and Profitability of Finishing Pigs Slaughtered at 130 vs. 110Kg (110kg 대비 130kg에 도축된 비육돈의 성장효율, 도체 품질 특성 및 수익성)

  • 이철영;권오천;하덕민;신호원;이제룡;하영주;이진희;하승호;김원기;김광위;김두환
    • Journal of Animal Science and Technology
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    • v.48 no.4
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    • pp.493-502
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    • 2006
  • The slaughter weight (wt) is a most important economic factor in swine roduction. The present study was undertaken to determine if it is feasible to increase the slaughter wt of finishing pigs to 130kg without significantly affecting the growth efficiency and carcass quality. One hundred and sixty gilts and 160 barrows born from lean-type Yorkshire×Landrace (YL)-dam and Duroc (D)-sire lines, which are most widely used for terminal breeding for pork production in Gyeongsangnam-do, were randomly allocated into 16 pens under a 2 (sex)×2 (slaughter wt; 110 vs. 130kg) factorial arrangement of treatments. The animals were fed ad libitum a diet containing 3,200kcal DE/kg and 15.5% crude protein. After slaughter at the predetermined wt, yields of trimmed primal cuts and physicochemical characteristics of the longissimus dorsi muscle (LD) were measured or analyzed. Average daily gain was greater (P<0.01) in barrows than in gilts (0.86 vs. 0.79kg), but it was not different between the 110- and 130-kg slaughter wt groups (P>0.05). Backfat thickness was greater in the 130- vs. 110-kg group in both sexes (gilts: 21.6 vs. 17.6 mm, barrows: 25.1 vs. 20.8 mm). The yield percentage of belly was greater in barrows than in gilts (21.2 vs. 20.5%) and also in the 130-kg vs. 110-kg group (21.4 vs. 20.2%). Major physicochemical characteristics of LD including the color, percentage of 48-h drip loss, 24-h pH and percentages of crude protein and fat were not influenced by slaughter wt. Marginal profit of the 130-kg vs. 110-kg market pig was approximately 󰠏20,000 won/head, which resulted primarily from the heavy carcass weight of the former exceeding the upper limit of the A- or B-grade. However, if it had not been for the carcass weight limit of the current grading system, a 130-kg market pig would have had a potential marginal profit greater than 20,000 won. Results suggest that slaughter wt of lean-line finishing pigs can be increased to 130kg without significantly compromising the growth efficiency and carcass quality and accordingly, the upper weight limit of the ‘good-grade’ carcass needs to be increased or abolished to accommodate the larger market pigs.

Study on the correlation between nutrition knowledge, dietary attitudes of guardians, and nutritional status of infants and toddlers - Nutrition-Plus program in Jeonju (보호자의 영양지식 및 식생활태도와 영유아의 영양상태와의 관계연구 - 전주지역 영양플러스 참여자를 중심으로)

  • Song, Eun Young;Rho, Jeong Ok
    • Journal of Nutrition and Health
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    • v.51 no.3
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    • pp.242-253
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    • 2018
  • Purpose: The purpose of the study was to identify the nutrition knowledge, dietary attitudes of guardians, and nutritional status of infants and toddlers as well as the relationships between these variables. Methods: The participants were selected among applicants for low-income family financing provided by the government and included 115 infants and toddlers as well as their guardians. Demographic data, nutrition knowledge, dietary attitudes, and nutrition intakes were assessed using a self-administered questionnaire, biochemical examination, and 24 Hour-Recall method. Results: The score for guardians' nutrition knowledge was 12.97 points of a possible 15, and the score for dietary attitudes was 53.38 points of a possible 75. The nutrition knowledge and dietary attitudes showed significant differences by education level (p < 0.05) and family structure (p < 0.05). Energy intakes of subjects aged 6 ~ 24 months and over 25 months were lower than the DRI for Koreans. The intakes of carbohydrates, protein, and fat of subjects aged 6 ~ 24 months and over 25 months showed no significant differences by level of nutrition knowledge or dietary attitudes. The intake of Ca of subjects aged over 12 months showed significant differences by level of nutrition knowledge (p < 0.05). The intakes of Thiamin of subjects aged 6 ~ 11 months and P of subjects aged over 12 months showed significant differences by level of dietary attitudes (p < 0.05). There was a small positive correlation between education level and nutrition knowledge as well as between dietary attitudes. Nutrition knowledge showed a positive correlation with dietary attitudes. There was a positive correlation between nutrition knowledge and Ca, Riboflavin, as well as Vit C levels. Conclusion: Therefore, it is necessary to consider an educational program for increasing the practical application of knowledge to nutrition management for improvement of nutrition intake in infants and toddlers.

Studies on the Insect Pests of Barley in Korea (한국(韓國)의 보리해충(害虫)에 관(關)한 연구(硏究))

  • Kwon, Yong Jung;An, Seung Lak
    • Current Research on Agriculture and Life Sciences
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    • v.3
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    • pp.129-150
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    • 1985
  • The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

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Effects of Estradiol and Pituitary Hormones on in vitro Vitellogenin Synthesis in the Eel, Anguilla japonica (뱀장어의 in vitro Vitellogenin 합성에 대한 Estradiol과 뇌하수체 호르몬의 영향)

  • KWON Hyuk-Chu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.2
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    • pp.282-290
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    • 1997
  • Hepatocytes of Anguilla japonica have been prepared using a collagenase perfusion technique. The isolated cells attached efficiently to fibronectin-coated culture dishes and subsequently formed monolayers in serum-free medium. These cultures maintained in appropriate medium at least for 10 days with minimal cell loss. The effects of estradiol and pituitary hormones on vitellogenin (Vg) synthesis were examined in primary hepatocyte culture of the immature eels. In fish, as in other oviparous vertebrates, estrogen is a major inducer of Vg synthesis. However, $estradiol-17\beta(E_2)$ alone was insufficient to induce Vg synthesis in cultures of eel hepatocytes. Combination of $E_2$ with growth hormone (GH) and/or prolactin (PRL) markedly stimulated Vg synthesis. Even in cultures exposed to $E_2$ or precultured without hormones for 8 days, $E_2$ alone could not fully induce Vg synthesis. The synthesis of Vg was dramatically increased when hepatocytes were cultured in medium supplemented with $E_{2}+GH+PRL$ for 6 days. At this point, even though GH and/or PRL were eliminated from the medium, Vg synthesis was not influenced by these factors during culture of further 3 days. These results indicate that pituitary hormones, in particular GH and PRL, play important roles in the regulation of Vg synthesis in primary cultures of eel hepatocytes.

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