• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.73-82
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• 1990

The experiment was carried out to study the influence of planting space and fertilizer application levels on some agronomic characters and yield in newly released semi-dwarf soybeans, Paldalbong and Dankyungkong. The number of branches per plant was not reduced by planting space from 60${\times}$10cm 30${\times}$15cm. These Semi-dwarf soybeans had good adaptability on high planting density. The number of pods per node on the main stem was different according to the planting space in Dankyungkong, but it was similar in Paldalkong except planting space 20${\times}$10cm. Regardless of planting densities and varieties, the number of grains per pod on upper node of the main stem was large. Coefficient of variation of pods and grains per node in the middle part of the main stem was small. The number of grains per plant was decreased in high planting density compared to low planting density, but the number of harvested plant per unit area was increased. Optimum planting space was 25${\times}$10cm in both varieties. The ability of nodulation was bigger in Dankyungkong than in Paldalkong.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.160-170
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• 2020

Railroads and roads are typical linear projects, and their networks are expanding nationwide. To minimize the impact of their development on the environment, ecological disconnection due to the parallel lines of railroads and roads is to be avoided as much as possible. In this study, to examine the environmental impact of railroad and road development, the characteristics of railroads and roads and the differences between them were examined through a comparative analysis of key evaluation items. Based on the result, the road development, unlike the railroad project, suggests items for establishing an efficient land use plan and soil protection as the key evaluation items. There are no specific evaluation items and criteria that can be used to examine the environmental impact of railroad lines located adjacent to roads. In this study, eight evaluation items were suggested by reviewing the relevant literature. In particular, in the strategic environmental impact assessment stage, which examines the adequacy and location feasibility of the plan, the minimum separation distance criteria were proposed to examine in advance the environmental impact of railroads located adjacent to the existing roads. The distances were examined for the previously operated routes, and a distance of less than 200 m was suggested to minimize the environmental impact. The results were compared with those in other studies and analyzed. The results of this study can be used as a basis for examining alternative routes that can minimize the environmental impact of adjacent railroads and roads.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.4
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• pp.287-298
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• 2000

The charge of distance and the change of tack between paired boats were measured by ship's distance measuring system fixed MCS in the main boat and MS in the following boat. The operating depth of the anchovy boat seine was recorded and analysed by self memory temperature/depth sensor in order to compare the relationship between the distance between towing boats and geometry of the anchovy boat seine net. The results are as follow, (1) When distance between paired boat was 5m, the fishing net was spreaded down deeply and unstably in accordance with bag net and flapper may be help to pass out anchovy school. (2) When distance between paired boat was 100m, vertical opening of the net was gradually increased with higher slope of towing depth in the square, bosom and flapper. Therefore, fishing efficiency could be decreased by preventing the entering of anchovy due to unstable shape of the bag net. (3) When distance between paired boat was 200m, the geometry of the anchovy seine was stable condition with the end of bag net was up while flapper was down and it may cause bad effect in fishing efficiency. (4) When distance between paired boat was 300m, the shape from wing net to bag net was gradually slow down and stable enough as well as good shape in bag net and flapper. (5) The ship's distance measuring system could be used for measurement and accurate control of distance between paired boat in accordance of anchovy recordings by fish finder in order to get higher fishing efficiency in anchory boat seine operation.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.4
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• pp.218-221
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• 2005

The present study was investigated in the Chittagong hill forest of Bangladesh to assess the feasibility of ginger cultivation under multipurpose forest and fruit tree species. There were three treatments such as i) ginger grown under open field condition, ie. full sunlight (T1), ii) ginger grown under Gamar tree (spacing of $90{\times}90cm$ (T2) and iii) ginger grown under guava tree (spacing $180{\times}180cm$) tree (T3). The experiment was laid out in randomized block design (RBD) and each treatment was replicated three times. From data it was observed that some morphological parameters of ginger such as plant height, number of leaves per plant, leaf length and leaf breadth were higher in the treatments T2 and T3 as compared to the treatment T1. A positive and linear relationship was observed between the weight of rhizome and yield of ginger which caused the highest yield of ginger ($23.63Mg\;ha^{-1}$) under guava tree species at partial shaded condition in the T3 treatment ($180{\times}180cm$), whereas the lowest yield ($15.64Mg\;ha^{-1}$) was recorded in the T2 treatment when ginger was cultivated under Gamar tree species at closer spacing ($90{\times}90cm$). Therefore, it was revealed that partial shaded condition favoured the optimum growth and yield of ginger, whereas the dense shade from intensively planted tree species badly affected the dry matter production and yield of ginger.

• Journal of the Korean Geotechnical Society
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• v.24 no.7
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• pp.5-16
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• 2008

Most of roadway tunnels have been constructed in the form of parallel twin tunnel in Korea. If parallel twin tunnel does not have a sufficient separation distance between tunnels, the problem of tunnel stability can occur. Generally, it is reported that tunnels are not influenced by each other when a center distance between tunnels is two times longer than tunnel diameter under the complete elastic ground and five times under the soft ground. In this study, the scaled model tests of closely-spaced parallel twin tunnel using homogeneous material are performed and induced displacements are measured around the tunnel openings during excavation. The influence of separation distance between tunnels on the behavior of closely-spaced tunnel is investigated. The experimental results are expressed by the induced displacement vector and progress of crack during construction and at failure. The results show that based on the analysis of induced displacement at the crown during construction, the additional displacement of the preceding tunnel induced by the excavation of following tunnel decreases as the separation distance between twin tunnel increases until the center to center distance is two times of tunnel diameter. Beyond this point, however, the additional displacement has become stabilized.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.31 no.1
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• pp.9-14
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• 2002

산업의 발전에 따른 도시화의 영향으로 대도시에서는 가용공간을 확보하기 위하여 건물의 고층화와 지하공간의 개발이 활발하게 이루어지고 있다. 최근 증가추세에 있는 초고층주상복합건물, 초고층아파트는 건물의 높이가 증가함으로 인하여 건축공사비의 증가는 물론 설비적인 측면에서는 저층부의 수압이 상승 하여 높은 수압과 수격작용(water hammer)에 대한 배관 및 기기의 내압강도와 안전대책이 요구된다. 또한 건물의 초고층화로 인하여 열원에서 공조기까지, 공조기에서 실내기기까지의 수직거리 (vertical distance)가 길어지게 되어 연장된 공조덕트 및 배관 의 길이로 인해 반송동력비의 상승에도 큰 영향을 미치게된다. 이러한 문제점을 해결하기 위하여 기기 및 재료의 선정시 내압을 고려하거나 기기의 적정배치와 조닝(zoning)을 통해 상기의 문제점을 해결하는 방법을 적극 채용하고 있다. 하지만 보다 근본적인 문제해결 방법으로 건물의 층고저감에 의한 건축공사비 및 연 간운전비의 절감을 통한 건물에서의 소비에너지량 감소로 부존자원이 부족한 우리나라의 에너지수급정책에 기여하여야 할 것이다. 본 고에서는 건축물의 층고저감 효과를 얻을 수 있는 공조시스템에 대해 전반적으로 기술하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.21-23
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• 2015

해상물류는 대형 선박일수록 톤당 수송비가 절감되므로 선박의 대형화 트렌드는 불가피한 반면 기존 항구의 항로와 부두의 확장은 현실적으로 어려울 뿐만 아니라 출입항 선박의 수가 증가하여 항로와 항내 조종구역이 상대적으로 좁아지는 효과가 빠르게 진행되고 있다. 선박의 항내조종 안전을 위한 연구가 필요한 바 선박조종의 현장경험을 정리한 비교지침을 가지는 것이 합리적이다. 항행중인 전후 선박간의 합리적인 안전거리, 부두 설계기준 초과선박의 접안시 운동량의 안전범위와 감소방안, 적정예선과 예선의 효과적인 사용방안, 부두앞 조종박지에서 선회권의 축소방안, 극저속에서의 조종성 확보방안, 안전한 자연감속의 범위와 급감속 방안, 비상시의 안전대책을 정리하고 다른 현장조선의 실무에 비교지침이 되고자 함이 본 연구의 목적이다.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.323-325
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• 2005

경제성장에 따른 인구의 집중화 및 도시기능의 고도화에 따라 전력기술분야의 많은 변화를 요구하게 되었다. 좁은 지역에 대용량의 전력을 안정적으로 공급하면서 환경과의 조화를 이루기 위하여 SF6개스를 이용한 개스절연개폐기(GIS)의 이용이 증가하였다. 이 논문에서는 중동국가에서 많이 건설되고있는 400kV 개스절연 변전소의 절연협조를 위하여 일반적으로 변전소 뇌과전압에 영향을 미치는 요소인 모선형태 및 구성, 피뢰기의 위치와 설치대수, 피뢰기의 제한 전압-전류특성, 모선의 길이, 피뢰기와 피보호기간의 이격거리 등을 고려하여 뇌침입시 변전소의 뇌과전압을 EMTP로 모의하여 개스절연변전소의 기기 절연강도를 결정하였다. 결정된 절연강도는 위의 모의결과로 얻어지는 발생예상 전압에 적정한 여유를 두고 IEC규격을 따라 선정하였다.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.6
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• pp.52-63
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• 1997

Non-circular gear has a good velocity ratio in high speed and heavy load without any slip, moreover, it can transmit various motion, using simpler structure than link and cam, automation mechainism. In case of designing and manufacturing non-circular gear. I suggest one of references in applying non-circular gear to industrial plant, and suitable range of application by pressure angle curvature and angle ratio

• Proceedings of the KOR-KST Conference
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• 1998.10a
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• pp.93-101
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• 1998

오늘날 사회가 더욱더 복잡해지고 도시규모가 확대됨으로서 사람들의 의식과 행태로 사회, 경제적 여건의 변화에 따라 다양하게 변모하고 있다. 이에 따라 교통계획의 대상이 다양화되어 지역적인 시각에서 국부적이고 단기적인 교통정책에 관심이 높아지고 있다. 이에 따라 본 연구에서는 토지이용지표의 하나인 접근성을 고려하여 이에 대한 통행거리에 따른 통행자의 교통수단선택이 어떻게 나타나고 분석되는 가를 도출, 장래 교통수요를 예측하여 교통계획을 수립하는데 있어서 교통수단에 대한 공급결정 및 교통시설에 대한 설치를 하는데 이들 수단이나 시설의 적정성 여부를 판단하는 지표가 되는 것이다. 이에 대한 근거로는 전통적인 4단계 수요예측방법을 사용하여 왔으나, 이러한 방법을 사용하는데에는 한계가 도출되어 최근에 사용되고 있는 개별행태모형 중에서 로짓모형을 이용한 방법을 선택하고 적용 가능한 가를 문헌적으로 접근하여 기본이론을 파악하였다.