• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.40-57
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• 1993

This paper aims to show the various aspects of migration in Kwangju merropolitan area, southwestern Korea, for a period of years 1980-1985. Migratory patterns are spatially extensive in countryside around Kwanfju, and due to high accessibility to the metropolitan area urban implosion emerges in the city. In Chonnam province where Kwangju is loca-ted, all cities and counties except for such in-dustrial areas as Yochon, and Kwangyang are experiencing population losses in terms of net migration by survival rate methods. Kwangju is the exceptionally one of in-migration areas in Chonnam, though its central part(Dong-Gu) is also an out-migrated area. Predominantly in-migration urban areas have high proportions of a student age group between 15-19 years, and that reflects the importance of the educational factor in migration analysis. The municipal authorities of Kwangju are planning to block the way of the middle sxhool students who live in the outskirts of Kwangju to entrance to high school in the city. Thant may stir up migrations into Kwangju for the elementary and middle school students, because the city id expected to provide educational opportunities higher and better than remaining Chonnam areas. Population of Kwangju would, therefore, grow as the students migrate into the city. The findings on the residential intra-city movement in selected 5 Dongs indicate that implications of a short-distance movement re noteworthy; neighbour to neighbour, and the nearest stop in the way from the outer Kwangju as well. Trends in a short-distance movement are in accord with Ravensteins's "law of migra-tion". But in casw of the inter-provincial migra-tion to Kwangju, the number of in-migrants from remoter Seoul is more than that from nearer Chonbuk province. Therefore it supports the fact that the movement between capital region and far off local cities overcomes a distance barrier. The temporary mobility for a day has been increased as the standard of living has improved and it reaches a peak on weekend or on con-secutive holidays. The number of temporal movers to Kwangju from capital region and Yongnam area, southeastern Korea has a greatincrease in terms of the frequency of the passengers' mobility, in particular on Myongjol(the ethnic and traditional festival day) in com-parison with on weekdays. By comparison with two largest Myongjols, the number of movers is more on Chusok(The Full Moon festival on lunar August) than on Sol (lunar new year's day). Annual peak point of weekday movers appears in August because of summer vacation. But the lowest one appears in June, which is related to the busy farming season. A patients' move for medical services in on the increase with a change of living conditions. It is especially true in the industrial counties such as Kwangyang and Yochon. By way of conclusion, it should be pointed out that one of the problems we face in survey of migration volume by the survival rate method is that the survival rate somtimes exceeds the value 1.0, in normal states of which should be under 1.0. it may be due to the shortcoming from the census statistics. We should not give therefore too much stress on the importance of migrations or moves as an element of changes in spatial pattern. In cinclusion, the results of the study show some geographic facts as the followings: 1. One of the outstanding phenomena in all types of movement is the seletivity of ages. The most important factors are related to education and employment. 2. Short-distance movement is carried out in accordance with Ravenstein's law, but in case long-distance movement, in-migration from capital region is prominent in spite of remoten-ces. The gravity between large cities such as Kwangju and Seoul, which has a frequent human movenent, causes urban implosion of small cities between those cities. 3. The temporary mobility for a day, in con-trast to that of permanent movement, is more related to transportation, and its volumes and annual variations are a large-scale. 4. Passengers' mobility is high in industrial cities. And the scope of patients' mobility is narrower than passengers'.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.8
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• pp.870-876
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• 2005

The multiple regression models which have two factors(population and commercial area) have been used to forecast the water demand in the future. But, the coefficient of population had a negative value because proper regional classification wasn't performed, and it is not reasonable because the population must be a positive factor. So, the regional classification was performed by principal component and cluster analysis to solve the problem. 6 regional characters were transformed into 4 principal components, and the areas were divided into two groups according to cluster analysis which had 4 principal components. The new regression models were made by each group, and the problem was solved. And, the future water demands were estimated by three scenarios(Active, moderate, and passive one). The increase of water demand ore $89.034\;m^3/day$ in active plat $49,077\;m^3/day$ in moderate plan, and $19,996\;m^3/day$ in passive plan. The water supply ability as scenarios is enough in water treatment plant, however, 2 reservoirs among 4 reservoirs don't have enough retention time in all scenarios.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.2
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• pp.94-101
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• 2015

To mitigate the greenhouse gas emission, many carbon capture and storage projects are underway all over the world. In Korea, many studies focus on the storage of $CO_2$ in the offshore sediment. Assurance of safety is one of the most important issues in the geological storage of $CO_2$. Especially, the assessment of possibility of leakage and amount of leaked $CO_2$ is very crucial to analyze the safety of marine geological storage of $CO_2$. In this study, the leakage of injected $CO_2$ through fault was numerically studied. TOUGH2-MP ECO2N was used to simulate the subsurface behavior of injected $CO_2$. The storage site was 150 m thick saline aquifer located 825 m under the continental shelf. It was assumed that $CO_2$ leak was happened through the fault located 1,000 m away from the injection well. The injected $CO_2$ could migrate through the aquifer by both pressure difference driven by injection and buoyancy force. The enough pressure differences made it possible the $CO_2$ to migrate to the bottom of the fault. The $CO_2$ could be leaked to seabed through the fault due to the buoyancy force. Prior to leakage of the injected $CO_2$, the formation water leaked to seabed. When $CO_2$ reached the seabed, leakage of formation water stopped but the same amount of sea water starts to flow into the underground as the amount of leaked $CO_2$. To analyze the effect of injection rate on the leakage behavior, the injection rate of $CO_2$ was varied as 0.5, 0.75, and $1MtCO_2/year$. The starting times of leakage at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 11.3, 15.6 and 23.2 years after the injection, respectively. The leakage of $CO_2$ to the seabed continued for a period time after the end of $CO_2$ injection. The ratios of total leaked $CO_2$ to total injected $CO_2$ at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 19.5%, 11.5% and 2.8%, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.183-192
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• 1998

The long-term observation of temperature in the coastal waters adjacent to the Wolsung Nuclear Power Plant has been carried out from November 10, 1996 to August 22, 1997, for approximately 280 days using a real-time temperature measurement buoy system. The sea-surface temperature was measured at every 10 minute using 10 buoys. The vertical structure of temperature was investigated near the outlet of the plant with two thermistor chains equipped with 10 sensors at 1 m interval The monthly averaged temperature was the lowest with spatial average of $12.8^{\circ}C$ in February and was the highest in August with spatial average of $19.6^{\circ}C$. The extremely low temperature was frequently observed between June and August, which seems to be the consequence of the intrusion of cold water near the southeastern coast of Korea. Distributions of the daily and hourly averaged temperature show that the highest temperature always occurred near the outlet of the plant and the warm-water patch moved along the north-south direction with the semidiurnal period. The semidiurnal fluctuation of temperature was also observed near the surface of the vertical profiles. The spectral analysis of temperature between February and April 1997 shows that the semidiurnal components prevailed near the outlet. It is likely that the semidiurnal components were due to the prevailing semidiurnal tide in this region. In August 1997, the diurnal components were dominant at the surface water of all stations except Station 12, which suggests that the warm water from the outlet of the plant has less effects in summer on the surrounding waters than the strong solar radiation.

• 대한예방의학회:학술대회논문집
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• 2002.07b
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• pp.3-17
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• 2002

국민건강은 국가발전의 기본조건이다. 국민건강은 건강한 어린이의 출산에서 비롯되고, 건강한 어린이의 출산을 위하여 여성이 건강해야 한다 따라서 여성과 어린이 건강보호와 증진을 위한 모자보건사업은 국가보건사업 중 최우선 사업으로 추진되어야 한다. 우리나라의 모자보건사업은 1960대부터 보건소를 통하여 가족계획, 산전관리, 안전분만유도, 예방접종을 중심으로 하였다. 1980년대에 들어와 전국민의료보험의 실현과 국민생활수준의 향상 등으로 산전관리 수진율과 시설분만율이 급격히 증가하여 1990년대 후반에는 거의 100%에 도달하였고, 가족계획실천율도 1991년에 79.4%까지 증가하여 합계출산율이 1.6으로 감소하였고, 어린이 기본예방접종률도 90%이상이 되어 전염병 발생률이 현저히 감소하였다. 전통적인 모자보건사업 관련 지표들이 이렇게 향상되자 일선 보건요원에서부터 중앙정부의 정책결정권자에 이러기까지 모자보건사업에 대한 관심도가 떨어져 중앙부처의 모자보건업무 담당 부서도 축소되고, 모자보건 사업도 쇠퇴하였다. 그러나 어린이와 여성의 건강실태를 자세히 들여다보면 심각한 문제들이 대두되고 있다. 시설 분만율의 증가에 따라 제왕절개분만율이 40%대까지 급증하였고, 모유수유률은 10%대로 떨어졌다. 어린이의 체격은 커지고 있으나 체력은 떨어지고, 비만한 어린이가 급증하여 당뇨병과 같은 성인병 유병률이 어린이들에게 증가하고, 사고에 의한 어린이 사망과 장애가 늘고 있다. 또한 청소년들의 흡연율과 음주률이 증가하고, 성적 성숙이 빨라지고 사회의 개방풍조로 성(性)활동 연령이 낮아지고 성활동이 증가하여 혼전임신과 성폭력이 증가하고 있다. 여성들은 일찍 단산하고, 폐경 연령은 높아지고, 평균수명은 길어져 중년기와 장년기 그리고 노년기가 길어져 각종 만성질환에 이환될 기회가 늘어났다. 이러한 시기의 중요 건강문제들은 뇌혈관질환, 폐암, 유방암, 골다공증, 뇨실금 등과 같이 해결하기 어려운 것들이다. 이렇게 어린이와 여성들에게 새로운 건강문제들이 대두되고 있으나 이에 대한 대응정책이 없었고, 따라서 새로운 모자보건사업이 개발되지 않았으며 일선 보건요원의 훈련도 없었다. 그리고 이러한 건강실태를 파악하여 대책을 마련하고, 보건사업을 평가할 수 있는 보건정보체계가 없는 실정이다. 1990년대 중반에 소수의 학자들이 어린이와 여성건강문제의 심각성을 제기하고, 모자보건사업 활성화의 필요성을 주장하여 보건복지부가 '모자보건선도보건사업'이라는 이름으로 1999년부터 2001년까지 3년간 23개 보건소에서 시범사업을 시행하였다. 이 시범사업에서는 한정된 자원으로 여성과 어린이 보건문제를 효과적으로 해결하기 위해 새로운 보건사업의 개발과 효율적으로 수행하는 방법의 개발에 역점을 두어 많은 성과를 거두었다. 시범사업의 경험을 바탕으로 2002년에는 전국의 45개 보건소로 확대해나가고 있다. 모자보건선도보건사업에서는 임산부가 대상이었던 기존의 모자보건사업과는 달리 신생아, 영유아, 학동기 어린이, 청소년, 그리고 신혼부부에서부터 장년기 여성에 이르기까지 사업대상을 확대하고 생애주기에 따라 지역사회 건강문제해결을 목표로 한 보건사업을 수행하도록 하였다. 사업수행 과정에서 보건소는 지역내 대학과 협력체계를 구축하여 기술적 지원을 받고, 보건요원의 교육 훈련을 통해 사업기획 능력과 전문지식과 기술을 향상시켰고, 보건교육에 필요한 시설과 장비를 구입하였고, 민간의료기관과 연계하여 보건서비스의 질을 향상시켰다. 모자보건 선도보건소에서 제공하는 서비스는 취약계층 중심의 보건교육, 상담 및 지도, 고위험대상자 조기발견 및 민간기관 의뢰 및 주구관리, 질병 조기발견을 위한 검진 의뢰, 지역 보건통계 생산과 관리, 그리고 지역내 가용자원 안내 등이며, 저소득층에 대해서는 민간의료기관에 의뢰 또는 검진비용을 지원하였다. 이와 같이 지역사회 민간기관과 협력체계를 구축함에 따라 대상자를 지속적으로 관리할 수 있는 정보를 공유하게 되었고, 건강증진 및 질병예방, 치료, 사후관리를 포함한 지속적이고 포괄적인 서비스를 제공할 수 있게 되었다. 특히 고위험 및 건강의심 대상, 임부와 장년기 여성에 대해서는 건강검진서비스를 과감히 민간기관에 의뢰, 위탁하친 보건소는 상담자, 정보관리자로서의 역할로 전환할 수 있었다. 그러나 사업관리자의 양적 평가에 대한 고정관념과 질적 평가에 대한 인식부족, 기본 생정통계와 정보체계의 미비로 인한 부정확한 통계생산, 사업요원의 전문지식과 기술 부족, 그리고 인력부족 등이 문제점으로 대두되었다. 효율적인 사업확산과 조기 정착을 위해 중앙정부의 일관성 있는 정책과 재정적 지원이 필수적이며, 보건정보체계확립, 그리고 공공보건기관과 민간의료기관간의 공식적인 협력체계확립이 필요하다. 사업추진 모니터링 및 평가, 조정을 위하여 중앙에 '모자보건 선도사업 기술지원단'을 구성하여 운영하고, 프로그램 운영이 잘되는 보건소를 특성화 보건소로 지원 육성하고, 사업요원의 업무 적정화를 위한 보건소 조직과 기존 보건사업체계의 평가와 재편이 필요하다. 보건사업요원의 자질 향상을 위한 지속적인 교육 훈련 시스템과 보건통계생산 관리를 위한 정보체계의 구축이 요구된다. 모자보건사업관련 보건교육자료를 수집하고 개발하여 전국 보건소에 공급하는 중앙 보건교육자료 및 정보센터가 필요하다.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.294-307
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• 2011

This experiment carried out to confirm characteristics of macrogranule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, application methods, and application times of formulation types. Particle of 500 g GG having average diameter of 2.5~3 mm was over 85 percent, the bulk density of the particle was $0.2\sim0.4g\;mL^{-1}$ and the particle was water floating granule. Active ingredients and external form of halosulfuronmethyl+mefenacet GG remained stable under condition of storage stability test. The disintegration time of the GG was faster as the water temperature was increased. But disintegration time was not affected by pH on the water conditions. By using hand, spoon and power applicator, drift distances of GG were 4~5m, 7 m and 10~12 m, respectively. GG showed good herbicidal efficacy and plant safety in all of the application methods such as, using hand, spoon, power applicator and RCAA. Application times of GG, GR, SC and TB by hand in $4,000m^2$ were 38 min. 4 sec, 42 min. 20 sec, 38 min. 10 sec and 21 min. 4 sec, respectively, but application time of GG by using RCAA was 1 min 32 sec. According to appearance and characteristics of formulation types, suspension concentrate (SC) and GG were possible formulation types for RCAA.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.106-116
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• 2001

A serious of studies on the fishing gear and system of the East Sea trawl fishery was carried out to improve the fishing efficiency and the working conditions. As the first step of these studies, the fishing gear and system of the traditional East Sea trawl were checked in order to solve the some problems, such as the poor sheering efficiency of net mouth, the inconvenient fishing system of the side trawl and etc. And then the fishing system was reorganized from the side trawl into the stern trawl by setting up the net drum system on the stern deck, and introduction of two types of new designed nets, one for mainly the midwater trawl and the other for the bottom trawl. The results of the field experiment on the modified system and nets can be summarized as follows : 1. the modified system was well worked and could save the man-labour by about 80%. 2. The sheering efficiency of the improved net, A type was improved to 20 m height and 30 m width in the net mouth, and that of B type net, to 10 m height and 33 m width, compared with 1.5 m height and 15 m width in the traditional net. 3. Catch efficiency of pink shrimp in A or B type net was better about 3 or 5 times than that of traditional net, and in B net, for herring and other bottom fishes is better about 2 times than that of the traditional net.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.53-60
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• 2006

Single well injection withdrawal tracer tests with bromide were carried out at two wells developed in a horizontally heterogeneous fractured rock. The hydraulic conductivity of TW-1 well was 5 times larger than TW-2 well, and the average linear velocity of TW-2 well was 1.8 times faster than TW-1 well. The difference of hydrodynamic dispersions of two wells in the fractured rock was studied with the analysis of concentration breakthrough curves and cumulative mass recovery curves of bromide with withdrawal time, and the estimation of average travel distance, pore velocity, longitudinal dispersivity and longitudinal dispersion coefficient. The average travel distances of bromide were estimated to be 3.00 m in TW-1 well and 5.62 m in TW-2 well. The average pore velocities for the injection/withdrawal phase were estimated to be $4.31\;{\times}\;10^{-4}\;m/sec$ in TW-1 well and $8.08\;{\times}\;10^{-4}\;m/sec$ in TW-2 well. Average travel distance and pore velocity were higher in TW-2 well because of small effective porosity. Longitudinal dispersivities were estimated to be 28.73 cm in TW-1 well and 18.49 cm in TW-2 well, and bromide transport was 1.55 times faster in TW-1 well. Longitudinal dispersion coefficients were estimated to be $5.14\;{\times}\;10^{-6}\;m^2/sec$ in TW-1 well and $6.06\;{\times}\;10^{-6}\;m^2/sec$ in TW-2 well, and diffusion area was 1.18 times larger in TW-2 well.

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.171-187
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• 2006

The status of heavy metal contamination was investigated using chemical analyses of stream waters and sediments obtained from Samsanjeil and Sambong Cu mining area in Goseong-gun, Gyeongsangnam-do. In addition, the degree and the environmental risk of heavy metal contamination in stream sediments was assessed through pollution index (Pl) and danger index (DI) based on total digestion by aqua regia and fractionation of heavy metal contaminants by sequential extraction, respectively. Not only the degree of heavy metal contamination was significantly higher in Samsanjeil area than in Sambong area, but its environmental risk was also revealed much more serious in Samsanjeil area than in Sambong area. The differences in status and level of contamination and environmental risk between both two mining areas may be attributed to existence of contamination source and geology. Acid mine drainage is continuously discharged and flows into the stream in Samsanjeil mining area, and it makes the heavy metal contamination in the stream more deteriorated than in Sambong mining area in which acid mine drainage is not produced. In addition, the geology of Samsanjeil mining area is mainly comprised of andesitic rocks including a small amount of calcite and having lower pH buffering capacity fer acid mine drainage, and it is likely that the heavy metal contamination cannot be naturally attenuated in streams. On the contrary, the main geology of Sambong mining area consists of pyroclastic sedimentary Goseong formation containing a high content of carbonates, particularly calcite, and it seems that these carbonates of high pH buffering capacity prevent the heavy metal contamination from proceeding downstream in stream within that area.

• Applied Biological Chemistry
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• v.45 no.2
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• pp.92-96
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• 2002

Present contamination levels of soils along the major roadsides of Seoul, Korea were investigated, and base-line data were accumulated for future use. Topsoil $(1{\sim}5$ cm) and subsoil $(20{\sim}50$ cm) from five districts (Gangdong-, Gwangjin-, Nowon-, Seodaemun- and Seongdong-gu) were sampled. The collected samples were airdried, passed through 2-mm sieves, and analyzed to determine the physicochemical properties including pH, EC, CEC, exchangeable cations (Ca, Mg, K, and Na), and heavy metal contents (Cd, Cu, Pb, and Zn). Soil textures of topsoils and subsoils were mainly loamy sand and sandy loam, respectively. The range of pH was $4.5{\sim}10$.0 with an average of 7.5 for both topsoil and subsoil, which is much higher than that of the forest soils in Seoul. The ranges of 0.1 N HCI extractable Cd, Cu, Pb, and Zn contents for both topsoils and subsoils were $0.0l{\sim}l.19$, N.D. (not $detected){\sim}228$.99, $N.D.{\sim}352$.54, and $2.97{\sim}332$.96 mg $kg^{-1}$, respectively. Most of the average heavy metal contents were lower than the concern level of the Soil Environment Conservation Act of Korea, but were much higher than those of the , forest soils in Seoul. Some sites were higher in heavy metal contents than the concern levels; in particular, the average Cu content in Seongdong-gu was much higher than the concern level, 50 mg $kg^{-1}$. Careful management of the soil to prevent the aggravation of the present contamination level and the dissemination of contamination is highly recommended.