• Earthquakes and Structures
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• 제8권6호
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• pp.1453-1461
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• 2015

In this article the non-linear behavior of the shear wall with low yield stress retrofitted with Glass Fiber Reinforced Polymer (GFRP) is investigated under pushover loading. The models used in this study are in ${\frac{1}{2}}$ scale of one story frame and simple steel plates with low yield stress filled the frame span. The models used were simulated and analyzed using finite elements method based on experimental data. After verification of the experimental model, various parameters of the model including the number of GFRP layers, fibers positioning in one or two sides of the wall, GFRP angles in respect to the wall and thickness of the steel plate were studied. The results have shown that adding the GFRP layers, the ultimate shear capacity is increased and the amount of energy absorbed is decreased. Besides, the results showed that using these fibers in low-thickness plates is effective and if the positioning angle of the fibers on the wall is diagonal, its behavior will improve.

• 아시안잔디학회지
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• 제13권4호
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• pp.201-212
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• 1999

In use of pesticides in golf courses has been increased steadily. Environmental concern as well as decrease in efficiency led the turfgrass management into an alternate approach of using beneficial microorganism to deal with turfgrass pests. This study was focused on the use of such microorganisms for improving cultural environment and minimizing the use of pesticides. Microorganisms antagonistic to turfgrass diseases were applied to zoysiagrass fairways and creeping bentgrass greens in Yusung country club. Tharch accumulation, disease occurrence, and other cultural environments were compared among the combinations of microorganisms and suppliemental N applications. The application of microorganisms antagonistic to turfgrass diseases improved turf resiliency. Thatch thickness was 3.03cm in the control plot but it was 2.11cm in plots treated by microorganisms, indicating significant effects of microorganism application on reduction of thatch accumulation. Number of microorganism that can decompose of cellulose was higher at the plots treated with useful microbial products and it was considered that existence of higher population of microorganisms resulted in reduction of thatch accumulation. In the evaluation of relationship between thatch accumulation and disease occurrence, greater thatch accumulation was observed at the golf courses which have been frequently infested by large patch. However, the rate of thatch accumulation varied among surveyed golf courses regardless of the year of turf establishment. Therefore, management practice which can be effective for reduction of thatch could result in large patch suppression. The application of microorganisms on the established turfgrasses reduced the occurrence rate of pythium blight and yellow path diseases, whereas occurrence of brown patch and dollar spot increased.

• Computers and Concrete
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• 제20권4호
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• pp.429-437
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• 2017

In this study, the effect of the tensile strength and ratio of disc spacing to penetration depth on the efficiency of tunnel boring machine (TBM) is investigated using Particle flow code (PFC) in two dimensions. Models with dimensions of $150{\times}70mm$ made of rocks with four different tensile strength values of 5 MPa, 10 MPa, 15 MPa and 20 MPa were separately analyzed and two "U" shape cutters with width of 10 mm were penetrated into the rock model by velocity rate of 0.1 mm/s. The spacing between cutters was also varied in this study. Failure patterns for 5 different penetration depths of 3 mm, 4 mm, 5 mm, 6 mm, and 7 mm were registered. Totally 100 indentation test were performed to study the optimal tool-rock interaction. An equation relating mechanical rock properties with geometric characteristics for the optimal TBM performance is proposed. The results of numerical simulations show that the effective rock-cutting condition corresponding to the minimum specific energy can be estimated by an optimized disc spacing to penetration depth, which, in fact, is found to be proportional to the rock's tensile strength.

• Toxicological Research
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• 제12권2호
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• pp.223-230
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• 1996

The increased embryotoxicity of the antifolate drug pyrimethamine (PYM) with concomitant dietary dosing of folic acid (FA) was examined in mice. The preventive effects of folinic acid (FNA) on PYM embryotoxicity were also examined. Six groups were constructed: PYM I (pyrimethamine 80 ppm), PYM II (pyrimethamine 150 ppm), PYM II+FNA (pyrimethamine 150 ppm and folinic acid 12 mg/kg/day), PYM II+FA (pyrimethamine 150 ppm and folic acid 350 ppm), FA (folic acid 350 ppm) and a control group. The agents were administered for 7 days from day 6 throughout 12 of gestation. PYM and FA were administered with mashed feed and FNA was intraperitoneally injected. The high incidence of fetal realformations was observed in the PYM II group; these included kinky tail, open eyelids, club foot, cleft palate, absence of the pulmonary lobe, diaphragmatic hernia, fused sternebrae, fused cervical or thoracic vertebral arch, among others. All embryos of the PYM II+FA group were resorbed. No realformed fetuses were observed in the PYM II+FNA group. These results show that the concomitant dosing of FA augments PYM embryotoxicity. The preventive effects of FNA were also observed.

• 한국조경학회지
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• 제38권4호
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• pp.25-34
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• 2010

본 연구는 골프장의 경기력과 운영관리 향상을 위한 평가지표들을 개발하고자 수행되었으며, 연구결과를 요약하면 다음과 같다. 이론연구 및 전문가 예비설문을 통해 가정된 골프장 조성 및 운영관리 15개 중간평가지표, 55개 하위평가지표 체계가 성립되지 않고 최종적으로 환경친화성, 회원서비스 수준, 진행원의 인적서비스 수준, 코스의 난이도, 코스관리수준, 운영관리 공정성, 접근성 및 입지성, 클럽의 전통성 및 클럽의 분위기, 코스의 우수성, 코스레이아웃 등 10개의 중가 평가지표 및 52개 하위평가지표로 재구성되었다. 골프장 이용자 선호도 평가지표의 중요도 결정요인을 분석한 결과, 코스의 관리수준, 포스의 우수성, 진행원의 인적서비스 수준, 코스레이아웃, 환경친화성 순으로 기여도가 높게 나타났다. 골프장 평가지표의 경로계수를 파악한 결과, 코스레이아웃 부문에서는 홀의 굴곡과 코스길이의 순으로 인과효과의 크기가 나타났다. 코스의 우수성에는 토너멘트 진행시설, 다양한 샷 밸류(shot value)의 순으로, 운영관리 공정성에는 대기의 편리성, 예약의 공정한 배정 등의 순으로 인과관계가 높게 나타났다. 클럽의 전통성 부분은 골프코스의 역사 및 환경적 특성, 지역의 역사문화가, 접근성 및 입지성과 관련해서는 지리적 조건이, 환경친화성에서는 농약 및 비료유출량, 수질오염 등이, 회원서비스 수준에서는 회원혜택과 직원의 친절한 응대 등이 상대적으로 인과효과의 크기가 높은 지표로 나타났다. 경기진행원의 인적서비스 수준 분야에서는 경기진행원의 친절한 응대, 경기진행원의 전문지식 정도가, 코스의 난이도 부분은 티잉 에어리어(Terming area)의 위치, 오비(Out of Bounds: OB) 및 해저드(Hazard) 말뚝 위치의 순으로 코스의 관리수준에는 러프상태 및 장애물 관리상태 등이 상대적으로 인과효과가 높았던 지표들로 나타났다. 향후 보다 세부적인 평가지표들을 도출하는 후속연구를 통해 골프장 이용자 선호도 평가지표 체계 모델을 완성하고, 국내외 골프장을 대상으로 평가지표들을 현장 적용하고 검증해 보는 과정이 뒷받침될 필요가 있다.

• 환경영향평가
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• 제26권6호
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• pp.524-537
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• 2017

사후환경영향조사 결과의 신뢰도 제고에 대한 문제가 대두되어 왔으나 조사결과에 대한 객관적인 검증을 수행한 연구가 미흡한 실정이다. 본 연구에서는 개발 사업에 의한 수질영향을 조사하였고 그 결과를 바탕으로 사후환경영향조사 시 수질분야에 결과와 비교 분석을 수행하였다. 토석채취사업장 내 오수처리시설 최종방류수에 Biochemical oxygen demand(BOD), Suspended solid(SS), Total nitrogen(T-N), Total phosphorus(T-P) 농도가 높게 나타났다. 사후환경영향조사 결과와 비교한 결과, 오수처리시설 최종방류수의 BOD, SS, T-N, T-P 농도가 사후환경영향조사 시 분기별 농도의 사분범위(Interquartile range, IQR)와 최소값과 최대값의 농도범위보다 높게 나타났다(p<0.05). 체육시설(훈련원) 조성사업의 경우에는 오수처리시설 최종방류수에 BOD, SS, T-N, T-P가 높은 농도로 검출되었고 BOD와 SS 농도는 협의기준을 초과하였다. BOD와 SS 농도는 사후환경영향조사 시 오수처리시설 최종방류수의 농도와 유의한 차이를 나타냈다(p<0.05). 이러한 연구결과, 개발 사업 시 오수처리시설 최종방류수에 대한 체계적인 수질 모니터링과 적절한 수질관리가 수행되어야 할 것이다. 또한 사후환경영향조사결과의 신뢰도 제고를 위한 방안이 모색되어야 할 것이다.

• 한국응용곤충학회지
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• 제45권1호
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• pp.67-74
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• 2006

본 연구는 골프장 잔디 해충의 종합적 관리를 위하여 잔디의 관리 과정 중에 곤충병원성 선충을 투입함으로서 굼벵이 방제의 효율을 향상시키고, 작업 공정을 축소시킴으로서 노동력과 경비를 절감시키며, 환경친화적 방제를 통해 골프장 잔디의 관리자나 이용자들에게 쾌적한 환경을 제공하기 위한 목적으로 수행하였다. 잔디의 예고는 곤충병원성선충의 병원성에 영향을 미쳤는데 꿀벌부채 명나방 유충을 이용한 pot 실험과 등얼룩풍뎅이와 주황긴다리풍뎅이를 이용한 야외실험 모두에서 잔디의 예고가 짧을수록 선충의 방제 효과가 높았다. 통기작업은 곤충병원성 선충의 종에 따라 굼벵이에 대한 병원성에 차이를 보였다. 굼벵이에 대한 병원성이 낮은 곤충병원성 선충은 통기작업과 병행하여 처리하면 병원성이 높아졌으나 병원성이 높은 선충은 큰 차이를 보이지 않았다. 통기작업의 수행시기도 곤충병원성 선충의 병원성에 영향을 미쳤는데 곤충병원성 선충의 처리 전에 잔디에 대한 통기작업을 하는 것이 굼벵이의 방제효과를 높였다. Steinernema carpocapsae 포천 계통 처리 시 등얼룩풍뎅이 유충 밀도 감소율은 선충 처리 전 통기와 선충 처리 후 통기 처리에서 각각 80.4%와 66%를 보여 무통기 처리의 35.4%에 비하여 높았다.

• 아시안잔디학회지
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• 제19권1호
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• pp.39-46
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• 2005

골프장의 문제해충들 중 등얼룩풍뎅이(Exonala orientalis) 3령충의 방제를 위하여 21계통의 한국산 곤충병원성 선충{Heterorhabditis bacteriophora 함양 계통과 Heterorhabditis sp. 202, 206, 217, Heterorhabditis sp. KCTC 0991BP 계 통, Steinernema carpocapsae 포천, S. longicaudum 공주, S. longicaudum 논산, Steinernema sp. 7, 24, 62, 55, 60, 64, 206, 207, 209, 210, 219, 227 계통}을 이용하여 실험을 수행하였다. 등얼룩풍뎅이 유충 한 마리당 200마리의 선충을 처리하였을 때, 14일 후 치사율은 Heterorhabditis sp. 202 계통이 $55\%$, Heterorhahditis sp. 205 계통과 H. bacteriophora 함양 계통이 각각 $50\%$의 치사율을 나타내어 Heterorhabditis속 선충들의 병원성이 $32.5\%$이하의 치사율을 나타낸 Steinernema속 선충에 비하여 높았다. 등얼룩풍뎅이 3령충 내에서 증식된 선충수는 Heterorhabditis sp. 202 계통이 273,064마리, S. carpocapasae 포천 계통이 273,043마리, Heterorhabditis sp. 217 계통이 248,887마리로 이들 선충들의 증식수가 일반적으로 많았다.

• 한국환경복원기술학회지
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• 제12권1호
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• pp.1-12
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• 2009

The purpose of this study is to discovered assessment items for improving athletic efficiency and management of golf courses. Through this, the study intended to provide basic data for creating competitive golf courses and management. Important assessment items were selected by inducing preliminary assessment items and conducting a preliminary survey and a main survey for specialists through a theoretical study. For the survey results studied, reliability and average value for importance were calculated using SPSS/PC Window Release 12.0. As assessment of importance by assessment area, in athletic efficiency assessment, course management level was the highest, followed by fairness of games and operation of games. In management assessment, importance of service level, information management, facility management, management of game assistants, etc. were high. As assessment of importance by assessment item, it was found that 'variety of golf shot' and 'the length of a course' were important in course layout. Also 'start interval among teams' and 'disturbance of play' were assessed as important items in game operation, while 'fair reservation' and 'rounding rotation time' were important in fairness of games. In addition, in information management, 'kind service of golf course staffs' and 'prompt reservation and notification' were found to be important assessment items. In facility management, all assessment indexes were over 4.0, which means all of them are important for quality of golf course and competitiveness. In membership service, 'appropriate price of goods for sale' and 'service for members' were relatively important assessment items. Further, in management of game assistants, 'qualifications and skillfulness of game assistants' was assessed as a very important index. Although the current study only selected important items to assess excellent golf courses, it is necessary to apply the study results to the actual sites and verify them for golf course both at domestic and abroad.

• 한국환경교육학회지:환경교육
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• 제24권1호
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• pp.88-101
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• 2011

This study aims to address the current status of ESD(Education for Sustainable Development) in Korean universities since UN DESD was launched in 2005, and to explore the possibilities and challenges in them. For this purpose we conducted questionnaire surveys and case studies on members of university communities which were engaged in green campus activities or interested in SD and ESD. Results of questionnaire surveys showed that most of those who answered the questionnaire were well aware of SD, but had comparatively low understanding of ESD. The highest number of respondents answered that since 2005 they had newly opened courses on SD or ESD, or added contents on SD or ESD to existing ones. Ratio of network participation among ESD-related universities was over 30%, and they appeared to have the highest partnership ratio with NGOs. Not many universities had policies for sustainable school management, and 'green space conservation and ecosystem protection' and 'energy and resource saving campaign and monitoring' were most common sustainable environment protection activities. Through case studies on eight universities, it was discovered that ESD programs in universities took various forms such as whole-university approaches, participatory courses and club activities. We suggest that it is needed to make efforts to find out good examples of ESD in Korean universities and share the results with university leaders, professors and staffs for further development of ESD.