• 상하수도학회지
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• 제29권2호
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• pp.223-231
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• 2015

District Metered Area (DMA) construction is one of the most cost effective alternatives for management of water loss (i.e., water leakage) and energy consumption (i.e., water pressure) in water distribution systems. Therefore, it's being implemented to numerous new and existing water distribution systems worldwide. However, due to the complexity of water distribution systems, especially large-scale and highly looped systems, it is still very difficult to define the optimal boundary of DMAs considering all the aspects of water distribution system management requirements. In this study, a DMA design methodology (or a DMA design model) was developed with Geographic Information Systems (GIS) and hydraulic distribution system model to determine the optimal DMA boundary.

• 산업기술연구
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• 제14권
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• pp.29-38
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• 1994

Neighborhood living boundary plan is offerd amenity living environment to inhabitants. This plan is contained that district unit division, appropriate living facilities disposition, and that one of the urban elementary plan in city political activities. The theme is on the primary School attendanced area in chun-cheon city, and analysis school attendanced area as an administrative district.

• 한국환경과학회지
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• 제2권2호
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• pp.103-113
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• 1993

The land and sea breeze over the Pusan coastal area is studied by three dimensional mesoscale numerical model. According to the results of the simulation experiments, both Pusan areas and Kimhae areas, the sea breeze began at 0800LST and the strongest at 1500LST and then at 1800LST. After midnight, the sea breeze changed about the land breeze and become weaker than that of the sea breeze in the daytime. Comparisons between calculations and observations showed that the characteristics of diurnal variation and v-component of the wind velocity relatively is similar to the Pusan areas. On the Kimhae areas, however, observations showed time lag which compared to the results of simulation experiments in the velocity of sea breeze and diurnal variation. From the above results, comparisons between calculations and observations is much more similar to the coastal areas than on the inland area.

• International Journal of Korean Welding Society
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• 제3권1호
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• pp.8-16
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• 2003

A major concern in Gas Metal Arc (GMA) welding process is the determination of welding process variables such as wire diameter, gas flow rate, welding speed, arc current and welding voltage and their effects on the desired weld bead dimensions and shape. To successfully accomplish this objective, 81 welded samples from mild steel AS 1204 flats adopting the bead-on-plate technique were employed in the experiment. The experimental results were used to develop a mathematical model to predict the magnitude of bead geometry as follows; weld bead width, weld bead height, weld bead penetration depth, weld penetration shape factor, weld reinforcement shape factor, weld bead total area, weld bead penetration area, weld bead reinforcement area, weld bead dilution, length of weld bead penetration boundary and length of weld bead reinforcement boundary, and to establish the relationships between weld process parameters and bead geomery. Multiple regression analysis was employed for investigating and modeling the GMA process and significance test techniques were applied for the interpretation of the experimental data.

• Ocean and Polar Research
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• 제28권2호
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• pp.175-186
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• 2006

There are disputes for oil and gas development between China and Japan in the East China Sea. These involve the area where China is already carrying out activities of oil and gas development and where Japan is proclaiming its EEZ. China insists that the Chinese activities on oil and gas development area are being carried out within the Chinese jurisdictional waters even if the median line principle of Japanese proclamation is applied in delimitation. Indeed, the permit for Japanese development is causing disputes between China and Japan because its permit allows development in the waters adjacent to Chinese development area. h the event, the core of this dispute around the oil and gas field in the East China Sea relates to issues of maritime boundary delimitation and issues of resources acquisition with both states. Chinese policy on oil and gas development is to first consider development issues in accordance with a median line principle where waters toward to China from the median line should be developed by China and the area toward Japan from the median line within the Chinese continental shelf should be jointly developed. However, the Japanese position is that the East China Sea should be jointly developed, and Japan hopes to eventually convince China to accept its median line delimitation. With on-going development of such issues, Korea should establish a strategy of negotiation based on analyses of resource distributional conditions and other strategic factors in the Korean delimitation area. In particular, Korea should prepare and make the best use of joint development zone established in an agreement between the ROK and Japan concerning the development of the southern part of continental shelf adjacent to both states.

• 한국습지학회지
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• 제12권1호
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• pp.83-94
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• 2010

본 연구의 목적은 부산광역시 서부산권의 낙동강하구역 일원을 대상으로 낙동강하구를 잘 이해하고 있는 각계각층 이해당사자 및 전문가들의 의견을 조사하여 이를 근거로 낙동강하구를 핵심보전지역, 완충지역, 전이지역으로 구분된 보전지역을 설정하고 각 보전지역별 현명한 이용 방안을 모색해 보고자 하는데 있다. 보전지역 설정은 이해당사자 및 전문가 설문조사 결과를 통해 설정된 보전지역 범위에 문화재보호지역과 습지보호지역 등의 법정보호지역과 비오톱보전가치평가도를 중첩시키고 보전지역 세부범위 설정에 관한 워크숍 및 브레인스토밍 등을 통한 전문가 의견을 반영한 세부조정과정을 거쳐 최종적인 보전지역을 설정하였다. 이 후 설정된 핵심보전지역, 완충지역, 전이지역 별로 현명한 이용방안에 대하여 모색하였다. 이 연구를 통해 낙동강하구에서의 보전과 개발에 관한 이해당사자간의 갈등을 조율하면서 지속가능한 발전을 도모할 수 있는 토대가 될 수 있을 것으로 기대한다.

• 대한조선학회지
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• 제21권1호
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• pp.21-34
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• 1984

This paper is concerned with the experimental investigation of transverse vibration characteristics in water of rectangular plates having an inner free cutout. Systematic experiments are carried out to investigate effects of the surrounding water on the added mass and the natural frequency of the plates due to the changes of the aspect ratio, hole size and eccentricity. The main subject is the clamped rectangular plate with a circular hole. For the purpose of comparative evaluations, some other common-type boundary conditions and hole shapes such as ellipses and rectangles are also investigated. Some of the results obtain are as follows; 1) For each given aspect ratio of the plate, there is a hole area ratio which gives a minimum value of the nondimensional frequency parameter for each mode. The hole area ratio increases as the order number of the mode increases. 2) The nondimensinal mass-increment parameter decreases as the aspect ration or the order number of the mode increases. For each given aspect ratio, the parameter the fundamental mode decreases monotonically as the hole area ratio increase. In cases of the second and higher order modes, however, each mode has a hole area ratio which gives a maximum value of the parameter for each aspect ratio more then 2/3. 3) Comparing elliptic holes with rectangular ones with same hole area ratio, nondimensional frequency parameters are almost same for each given ratio of the shorter axises to the longer one. 4) The influences of difference in boundary condion on nondimensional frequency parameters in water are similar to those in air.

• The Korean Journal of Ecology
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• 제21권5_2호
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• pp.501-518
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• 1998

Mt. Paektu(2,749.6m)m the biggest mountain in Northeast Asia, located on the border line of Korea and China is characterized as an aspite with broad gentle mountain area and rich biota. however, it seems that the study of forest vegetational feature or vegetation zones in the whole area of this mountain is not yet sufficient in spite of contribution by many investigators. in this paper thermal climatic approach was carried out for the determination of vegetation zones of the mountain with the meteorological data of four stations including Cheonjj and various vegetational data. the application of Warmth Index and/or coldness Index(Kira 1977) for the determination of forest vegetation boundary was useful also here, and their boundaries largely coincided with those of thermal indicies obtained in the Korean Peninsula(Yim and Kira, 1975), including the lapse rate of air temperature along increasing elevation. However, in the mountain the boundary of vegetation zones in not clear like those of mountains in Korea. It may be due so the topographic differences between this area and the Korean Peninsula. Besides, the broad ecotones between different vegetations in this area support the vegetation continum concept rather than the unit concept, and the limit of timber line or tree line reflects various hypothesis(Steven and fox 1991). Therefore, for the explantion of vegetation zone of this area should be considered topography or soil condition, for example, as known the hierachy of ecological units (zonobiomes, orobiomes and pedobiomes, Walter, 1973).

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 하계학술발표회
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• pp.86-87
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• 2001

• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.11-16
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• 2007

Since public awareness on the importance of sea is increasing, a number of states have ratified the United Nations Convention on the Law of the Sea. However several problems on marine boundary making are raising due to the ambiguity of law and importance of sea area. The purpose of this study is to find a logical principal through overall consideration on decision of baseline points which is a criteria of maritime boundary delimitation. Accordingly, this paper considers the current status, problems and measures for marine boundary making and then presents an alternative on it.