• Ocean Systems Engineering
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• 제3권1호
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• pp.71-77
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• 2013

The effective tracking area of ultra short baseline (USBL) systems strongly relates to the safety of autonomous underwater vehicles (AUVs). This problem has not been studied previously. A method for determining the effective tracking area using acoustic theory is proposed. Ray acoustic equations are used to draw rays which ascertain the effective space. The sonar equation is established in order to discover the available range of the USBL system and the background noise level using sonar characteristics. The available range defines a hemisphere like enclosure. The overlap of the effective space with the hemisphere is the effective area for USBL systems tracking AUVs. Lake and sea trials show the proposed method's validity.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.56-57
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• 2017

In recent years, new construction methods have been required to reduce the construction cost and increase the available area in an environment where construction work is frequently performed in a narrow urban area like Korea. As a result of these studies, slim floor composite beam has been suggested. Slim floor composite beam can reduce required depth because web of steel beam is embedded in the slab, so it is effective to reduce floor height and increase the available area. The purpose of this study is the floor height reduction evaluation by comparing system consisting of reinforced concrete, steel, and slim floor using square-shape steel pipe. After doing structural design for a typical plan, checked effectiveness by comparing each design plan. It is proven that slim floor composite beam can reduce required depth effectively comparing required materials of other system.

• 한국시뮬레이션학회논문지
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• 제10권4호
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• pp.11-20
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• 2001

In the IMT-2000 networks, the model of micro/pico cell is suggested for transmission of multimedia service. Hence, the efficient method is required for processing of mobile calls in micro/pico cell. In the central urban area, mobile calls may be dynamically increased because of many mobile users. And microcel]/picocell size has small size, handover calls will be more increased. Therefore, many of mobile calls is occurred at a cell in the central urban area, so channel requests for these calls will be increased in the call. In this paper, we propose a scheme, FTC(Fault Tolerant Channel allocation) which is the channel management method for hard handover and new call in a mobile cell of central urban area. When available channels in the cell are consumed, the FTC investigates channel states of neighbor cells in the RNC(Radio Network Controller) or BSC (Base Station Center), and provide available channel for mobile call. The ]no scheme is analyzed and compared with existing channel management method by simulation.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.23-33
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• 2015

This study was conducted to provide the preliminary data on preparation for policy decisions regarding the groundwater supply scheme for N. Korea vulnerable to drought. Agricultural activities oriented to upland field due to the mountainous terrain more than 79% as well as the diversity of rainfall distribution over the country make more vulnerable to structural problems in the drought in N. Korea. Therefore, in anticipation of the expansion of exchange policies in agricultural sector, the available amount of groundwater needed for sustainable water resources supply was estimated for each administrative district after analyzing alluvium and hydrogeology distribution in N. Korea. Overall, the available amount of groundwater was estimated to 22.3 billion m³ (0.18 million m³/km²). The available amount of groundwater per unit area in Ryanggangdo and Gaesungsi was appeared very high in each of 0.56 and 0.39 million m³/km², respectively, and it would be interpreted that two districts have relatively wide area of volcanic rocks and alluvium with highly permeable characteristics, respectively. Finally, to maximize the utilization of this study result, the available amount of groundwater distribution map was developed on the basis of the 1 × 1 km grid network over the entire N. Korea.

• 한국터널지하공간학회 논문집
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• 제14권2호
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• pp.141-157
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• 2012

TBM 공법 적용을 위한 도로터널 단면의 국내 외 설계사례와 시공사례 및 터널단면 설계기준을 조사 분석하였다. 교통량에 따라 차로수의 규모 및 내부형상(단층 혹은 복층)이 상이하였고, 상 하부의 여유공간은 환기, 방재시설 및 유지관리 공간 등으로 다양하게 활용하고 있음을 확인하였다. TBM도로터널의 구성요소별 면적비를 확인하기 위하여 2차로 규모의 표준단면을 가정하고, 길어깨 폭원변화에 따른 내공단면 구성요소(시설한계 수용공간, 상부여유공간, 하부여유공간)의 단면적비를 분석하였다. 아울러 도로터널에 필수적으로 설치되는 차도 슬래브의 지지형식별 소요두께를 구조해석을 통하여 산정하였고, 산정된 벽체 및 슬래브 두께와 하부 여유공간의 상관관계를 분석하여 유효단면적 범위를 제시하였다.

• KIEAE Journal
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• 제5권3호
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• pp.17-24
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• 2005

Until today, rainwater management was processed without disposing the peak discharge, which was due to rainfall, to provide stability against flood damage. In this process, the natural hydrologic cycle changed quickly, and because of this, some problems that could harm human beings and the environment arose. These problems need to be addressed accordingly. One of the proposals was to carry out decentralized rainwater management through a natural hydrologic cycle on site, including utilization, infiltration, detention, and retention of rainwater. This study aims to set the direction of applicable decentralized rainwater management to housing complex in Korea. Therefore, spacial properties in urban housing complexes were analysed such as the impervious area-to-land ratio, the green area-to-land ratio, artificial land-to-land ratio etc. As the result of this study, when a housing complex was small and developed by reconstruction, the impervious area, artificial land, the green area in the artificial land-to-land ratio were high. So, direction of decentralized rainwater management of these housing complexes is available to utilize and detain rainwater. On the other hand, those of big housing complexes in land development district were low relatively. So, direction of decentralized rainwater management of these housing complexes is available to infiltrate and evaporate rainwater.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.153-153
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• 2018

Water-Energy-Food (WEF) nexus is a new holistic resources management concept that considers the interconnections among resources for sustainable resources planning and management. The current challenge is to fulfill the required demand in the lack of available resources. A traditional way to provide more available resource is by increase in production, but it caused increment of indirect demand of other interlinked resources. Importing resources from other area (where local supply is redundant) is another option to secure local resources with additional economic expenditure. The WEF nexus-trading model adapts the previously developed nationwide nexus simulation model with additional input parameters and functions to simulate trading scenarios. In general, the analysis starts with the quantification of local resources deficit (potential importing amount) and redundancy (potential exporting amount) of each area. Then, a trade module is initiated by determining possible donor area and importation amount. Finally, the nexus simulation for all area is re-run to determine final resources supply-demand results including the trading amount. The trade option provides an opportunity to meet local demands without draining local resources. However, the production capability of donor area may limit the importation amount. The newly developed trade option allows more alternatives for stakeholders to determine resources management plans.

• Journal of Astronomy and Space Sciences
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• 제15권1호
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• pp.229-234
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• 1998

We study on a terrain contour matching algorithm using Radial Basis Functions(RBFs) for aided inertial navigation system for position fixing aircraft, cruise missiles or re-entry vehicles. The parameter optimization technique is used for updating the parameters describing the characteristics of an area with modified Gaussian least square differential correction algorithm and the step size limitation filter according to the amount of updates. We have applied the algorithm for matching a sampled area with a target area supposed that the area data are available from Radar Terrain Sensor(RTS) and Reference Altitude Sensor(RAS)

• 한국식생활문화학회지
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• 제5권2호
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• pp.207-215
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• 1990

In this study, the types and characteristics of rice cake, cookies were investicated in the rice grown area-Korea, Japan (Tokyo, Osaka), China (Hongkong), Thai (Bangkok, ChiengMai), Indonesia (Bali, Jakarta), and Philippine (Manila). 1. Rice cakes and cookies were made from rice powder and rice granule. Specially, there were two kinds of basic rice powder one was rice powder in dry and the other was rice juice grinded with water on the millstone. Rice juices were named in China, MeeChang, in Manila, Galapong, in Bangkok, rice powder. 2. The kinds and numbers of steamed rice cakes were the most available in all investicated area. In Hongkong, Bangkok, ChiengMai, and Manila, beatened or kneaded rice cakes could not be seen almost. Only in Hongkong and Bangkok, fried rice cakes were available, while in Japan, boiled rice cakes were not seen almost, and also baked rice cakes were not seen in Korea, Hongkong, Bali, Jakarta. 3. In the east-south Asian area, except rice and glutinous rice, coconut and palm fruits and banana were using in recipies of rice cakes and cookies. They gave soft and tender mouth feeling, white color, and good emulsifying status. 4. The kinds and numbers of rice cookies were the most available in Bangkok, but in Bali and Jakarta, the least. The cookies of Japan had similar texture and shape to rice cake while most of cookies in Hongkong were fried in oils. In Korea, the kinds and numbers of rice cookies were less than those of rice cakes.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.61-66
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• 2004

In this paper an effort is made to develop an innovative spatial arrangement concept pertaining to ship building industry. The spatial scheduling is the problem that concentrates on effective planning of available space and arrangements of blocks and in a priority manner. In order to create an effective spatial scheduling. a database providing the priority has to be available to make the erection sequence. Such a system works hand in hand with erection sequence generator program The erection sequence program works on the conventional network analysis method which uses a typical parent-children idea for the calculation of the ENT(possible earliest network start time) and LNT(possible latest network start time). This program works in a cyclic manner taking turns by calculating the ENT in upward trace and LNT on the return trace thereby generating the entire erection sequence diagram for the requisite problem The generated database serves as an input data for spatial scheduling problem. When the system works it takes into consideration the entire system based on heuristic concepts as mentioned. There system uses the spatial aspects such as the available area of the P. E area and plan area of the corresponding blocks and its priority of erection from the erection sequence generator program develops the spatial scheduling arrangement. In this paper using all these concepts an innovative spatial schedule development system developed.