• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.209-218
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• 2011

The present study proposes a new estimation relationship for the transmission rate of the steel breakwater which is expected to make up for the weakness points in existing hard solution for shore protection. The steel breakwater consists of the wave dissipator of the dual horizontal plates, the supporting columns and their foundations, and thus its respective designs should also be conducted one by one. Furthermore, the breakwater has to ensure both functions of shore protection and structure stabilization. The study produced experimental data for the stability and safety investigation of the steel breakwater. The forces acting on the steel breakwater were classified into two categories, one is vertical up and down loads for the pile resistance and the other was maximum difference of the vertical load acting on horizontally different position for the torsion. The study applied the stability force produced by the summation of maximum pressure at each point and the safety force acting on each point simultaneously. The regular wave corresponding to the significant wave was utilized for measuring wave pressure and force. The study showed the method for the proper position of submerged upper plate by considering occurrence frequency of tide level. The design process finally determined by trial and error is proposed in the present study.

• Korean Journal of Environment and Ecology
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• v.20 no.3
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• pp.331-339
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• 2006

Inhabitant patterns of the legally protected species and the characteristics of fish fauna in the Pyeongchang River, Korea, were studied from April to July 2004 by selecting 6 sites. The number of fish samples in this period were 2,448 in 35 species of 9 families. A total of nineteen endemic species (54.29%) were presented and those were Hemibarbus mylodon and Acheilognathus signifer. The highest frequency was shown in Zacco korean us (34.84%) and Pungtungia herzi (10.25%) and Coreoleuciscus splendidus (6.86%) were the next. In addition, The highest biomass was found in Z. koreanus (5,580.2g) and Coreoperca. herzi (1.241.2g) and C. splendidus (1,207.0g) were the next. When comparing the distribution of the legally protected species in within the Han River system, the highesting distributions were determined in the Pyeongchang and Dong River (6 species). The ratio of individuals in the Pyeongchang River was shown to be higher (10.62%) than that of other lakes and streams. In conclusion, more precise protection and protective plans were needed in order to maintain the lake ecology in good status because the Pyeongchang River is relatively well protected from the anthropogenic disturbance in the legally protected species including the endemic species.

• Korean Journal of Environment and Ecology
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• v.25 no.6
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• pp.893-902
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• 2011

The purpose of this study was to survey structures and growth conditions of Pinus densiflora village groves, and to establish management strategies for their desirable growth and conservation. Twelve village groves were selected in western Gangwon province for the study. The age of the study groves ranged from 50 to 200 years. Average dbh (diameter at breast height) and density of trees for each study grove were 27~52cm and 0.5~9.3 trees/$100m^2$, respectively. Soil environments were favorable to Pinus densiflora growth in the majority of the study groves, but 2 study groves with sandy soils showed considerably poor nutrient contents. Low tree vitality was found in some of the study groves due to poor conditions of root growth from soil fill and trampling. There were detachment of cambial tissue and damage of stem cavity at 6 study groves, which were caused by artificial injury, careless pruning, and frost damage. Light disease damage by Rhizosphaera kalkhoffii and phomopsis blight were found at 6 study groves. Light pest damage by Thecodiplosis japonensis was also found at 6 study groves, but the pest damage at 2 study groves was relatively considerable. Thus, major factors limiting normal growth of Pinus densiflora village groves were infertility, soil fill and trampling, stem damage, and disease and pest. Desirable management strategies were explored to solve growth-related problems and to conserve the study groves. The management strategies included fertilization of organic matter and lime, removal of soil fill, soil plowing and graveling, wood-trail installation or woodchip mulching, supply of wood fences and protective frames, surgical operation for damaged stems, vitality enhancement, and trunk injection to improve growth environments or control stem damage and disease/pest.

• Particle and aerosol research
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• v.11 no.3
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• pp.63-75
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• 2015

Atmospheric environment in Korea is influenced by outside, especially China. The concentrations of air pollutants in China have showed decreasing trends since 2000. However, these concentration levels in China are still higher than other developed countries. The Chinese Government has tried several measures to control the air pollution. In this study, the details of the amendments and smog reduction strategies in China, especially for Beijing are reviewed and the strategies for Korean side to promote cooperation in Northeast Asia are suggested and discussed. The Chinese State Council amended the Environmental Protection Provisions and Clean Air Act and announced The Action Plan for Air Pollution Control (2013-2017), focusing on three key regions, Beijing-Tianjin-Hebei area (Jing-Jin-Ji), Yangtze River Delta (YRD) and Pearl River Delta (PRD). These policy actions and plan are mainly for the reducing coal usage and emissions from vehicles. It is suggested that, Korea should actively promote multi-national cooperation in the region to take an initiative role in environmental areas.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.498-511
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• 2012

Mountainous wetland have many species such as II grade endangered species of wild flora and fauna(Drosera rotundifolia) and environmental indicator species(Utricularia racemosa, Habenaria linearifolia, Parnassia palustris, Molinia japonica, etc.). Accordingly, the mountainous wetlands is very important. However, most mountainous wetlands will disappear by natural or artificial aridness processes. Thus, it needs to manage mountainous wetland for protecting from aridness. This study has found out the wetland status of the environmental ecology and aridness processes moreover, it has suggested ways of improving wetland conservation plan and wetland aridness management plan. According to the results of topography structure survey, Hwaeom wetland's altitude is ranged within 750~810m(87.4%), and slope is less than $10^{\circ}$. There was ideally suited mountainous wetland. However, the water supply(1.6 meters depth and 0.8 meters wide) was built on under the wetland. For that reason, there was concerned about the aridness processes by sweeping away peat layer and dropping the water level. The distribution area of hygrophyte was narrowed to 6.7% whereas, woody plants and xerophytic plants was achieved a dominant position. If it leaves the situation as it is, the mountainous wetland will be developed next succession as forest ecosystem. Therefore, in order to sustain the mountainous wetland from aridness, it is set to the base direction of conservation and management as main schemes. Moreover, we have suggested that setting the vegetation conservation and management area which considering a ecological vegetation characteristics, managing the ecotone vegetation, setting the buffer zone for protection of ecological core areas, protecting the mountainous wetland indicator species and designating the management vegetation. In conclusion, in order to sustain and maintain a soundly wetland ecosystem, it needs to several management of wetlands damage factors. 1) suppression of the excessive groundwater to basin, 2) stabilization of wetland via hydrologic storage, 3) suppression of changing and transforming wetland into forest by succession via management of xerophytic plants.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.314-325
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• 2014

We studied fish fauna at 10 study sites in Ungcheon stream for 4 times from April to October, 2011 to investigate the influence of artificial structures such as dam (with fish-way) and weir (without fish-way), and abandoned mine on fish community. A total of 12 families, 36 species of fishes were collected. Dominant species was Zacco platypus (23.4%) and subdominant species was Zacco koreanus (20.5%). Ten species (27.8%) of Korean endemic species and Micropterus salmoides, exotic species, were observed during the study period. Endangered species of Korea such as Pseudopungtungia nigra and Liobagrus obesus, and Korean endemic species, Coreoperca herzi, which are vulnurable for water quality and had been observed in previous study, were not identified in this study. According to the cluster analysis, Ungcheon stream were divided into three groups consisting upstream (St.1, St.2, St.3), midstream (St.4, St.5, St.6, St.7), downstream (St.8, St.9, St.10). Community structure similarity between upper and lower site of Boryeong dam with fish-way (St.6-St.7) was high, whereas that of weir, lack of fish-way (St.7-St.8) showed little similarity indicating that fish-way was required. According to the canonical correlation analysis, high level of conductivity and salinity at upstream was detected and Misgurnus mizolepis, and endemic species of Korea such as Silurus microdorsalis, Coreoleuciscus splendidus and Iksookimia koreensis were observed at this part of the stream. Since Korean endemic species, Squalidus gracilis majimae cohabit with exotic species, M. Salmoides at downstream whose width is wide and water velocity is low, protection was needed for these endemic species.

• Journal of the Korea Convergence Society
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• v.2 no.1
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• pp.31-36
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• 2011

This study was performed to investigate the problems of using asbestos for dental technicians. Samples for analysing were sampled by personal sampler in 40 sampling points of 10 dental laboratories in Daegu city from December 2010 to January 2011 and counted with phase contrast microscopy. The results were as follows: 1. Asbestos concentration(geometric mean) of 40 sampling points in 10 dental laboratories was 0.0061 f/cc and it was under recommended industrial and indoor air standard, but the concentration of asbestos in only two dental laboratories was over indoor recommended standard. 2. The concentration of asbestos in processing room and burnout room was 0.0099 f/cc and 0.0037 f/cc, respectively. 3. The mean concentration(GM) of asbestos by kinds of casting ring liners was 0.0159 f/cc in dental laboratories using industrial asbestos, 0.0104 f/cc in them using asbestos containing ring liners, and 0.0026 f/cc in them using non-asbestos ring liners. Casting ring liners using in dental laboratories should be substituted with non-asbestos liners, because most of dental laboratories were using asbestos containing ring liners and a few of them showed higher concentration than recommended standard.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.71-84
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• 1997

유기농산물은 질 좋은 농산물이며 그 생산농법이 환경친화적인 것으로 이해하고 있어 참여농가수도 증가일로에 있고 소비자들에 의한 유기농산물 구입 역시 점차 증가 추세에 있으나, 한국유기농업은 국제적 유기농업에 다르게 잘못 정의된 채 확산되고 있어, 그 핵심기술의 환경영향평가의 과학화에 대한 시대적 요청과 유기농업 기본규약 제정 필요성이 학계 일부에서 제기 되고 있는 등 한국유기농업은 최근 발전을 위한 진통을 겪고 있다. 이에 본 논문은 한국유기농업이 태동된 배경과 70년대 말로부터 80년대 초에 걸쳐 태생된 한국유기농업이 국민적 관심을 얻게된 배경과 정농회, 한국유기농업협회, 한국자연농업협회, 한 살림 등의 유기농업단체와 한국유기농업학회, 환경보전형농업생산소비단체협의회, 흙살림연구소 등의 발전과정 및 활동을 소개하고 있다. 또한 서울에서 개최된 IFOAM Asia대회, 한국자연농업협회의“자연농업연구소”, 한국유기농업협회의“건강과 자연농업”등에 관해서 뿐만 아니라 우리 정부의 21세기를 향한 농림환경정책중 유기농업부문에 대한 각종 장기지원책, 즉 중소농대책의 일환의 유기-자연농업 지원책, 유기농산물에 대한 품질인증제 및 팔당상수원보호구역내 유기농업지원 등이 소개되고 있다. 한편 한국유기농업기술의 핵심내용이었던 유기질비료 과다시용 문제가“유기농산물 채소의 고 질산염 함량”으로 촉발된 식품안정성 논쟁 후에 유기질비료의 추천시용량이 다다익선적 개념에서 80t/㏊으로 낮아졌다가 다시 50t/㏊으로 낮아졌으며 1996년 6월부터는 20t/㏊로 크게 낮추어 졌음을 보고하고 있다. 또한 일부 선도적 유기독농가의 경험적 기술이 토대가 되어 성립된 현 유기농업기술은 과학적 기술검증을 거쳐야 함과 퇴비사용 만으로 실시하는 현 유기농업 기술에 의해 야기되는 근권내 질산 미치 인산염 집적을 회피하기 위해서는 윤작, 녹비작물 및 두과작물의 재배로 토양비옥도 향상을 통한 유기농업 기술 개발이 필요하며 IFOAM 기본규약과 FAO/WHO Codex의 핵심 내용을 수용하는 한국유기농업 기본규약 제정이 제정이 절실히 요구됨을 강조하고 있다. 마지막으로 한국유기농업의 핵심기술에 대한 환경영향평가와 기본규약제정 필요성을 역설하고 한국유기농업의 과학화와 질 좋은 유기농산물 생산을 위해 노력하고 있는 소비자 문제를 연구하는 시민의 모임 등 몇몇 단체들의 최근 활동이 언급되고 유기농업에 대한 농과대학내 연구와 강의 등이 소개되었다.

• Journal of forensic and investigative science
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• v.2 no.1
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• pp.23-31
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• 2007

Apartments are built in small countries to accommodate densely populated cities and maximize urbanization. Many apartment complexes have been built in recent reconstruction or redevelopment projects. An increase in crime has resulted due to residents living in a narrow space. Larceny is the most commonly reported crime in apartment complexes. Apartments can be classified as stairway, hallway, or plane surface. This study compares and analyzes the frequency of theft by apartment type to assist in creating a safer residential space. In America and England, scholars studied to make a safer residential space, and have applied the theory of 'the Defensible Space' and 'Crime Prevention Through Environmental Design(CPTED)' since 1970s. Korean apartment design now reflects CPTED in new apartment construction. In this study, 12 apartment complexes were selected in Changwon city to conduct analysis of theft in selected complexes. The study will cover housing invasion theft, motorcycle and car theft and snatching. The most frequency larceny is motorcycle and car theft, the second is housing invasion theft, and the least frequent is snatching. More residents' motorcycles and cars are damaged in a hallway style apartment. More frequently inhabitants have their possessions snatched on a stairway form. 1) When we build new apartment complexes, we must plan to improve territoriality and enhance a natural surveillance by reinforcing dwellers' relationship. Through planning we can prevention the larceny in apartments.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.86-106
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• 2019

We investigated the environmental conditions of natural habitats of T. nuda. The species was found on rocky northern hills ($60{\sim}90^{\circ}$) near the stream where the sea level ranges 95~145m. The average annual temperature of the habitats was lower than other places of South Korea. The differences of the lowest and the highest of the year was significantly huge than any other places. Plants were growing at the edge of stream that water reached but not submerged. Most of plants were found in North, Northeast or Northwest. It is suggested that these species require moist and low sunlight for growth. The common vegetation along with the T. nuda includes Mukdenia rossii, Selaginella rossii, Calamagrostis epigeios, and Rhododendron yedoense f. poukhanense. The dominance values and sociability of T. nuda were below 3 in all studied habitats and the variance of the number of individuals among the habitats was very high. As the optimum habitats for the T. nuda are decreasing due to the extreme precipitation patterns. It is also expected that the number of T. nuda will be decreased in the future. Therefore restoration activity in situ or ex situ must be conducted to conserve this valuable plant species.