• 한국농림기상학회지
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• 제8권3호
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• pp.183-189
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• 2006

건물 생산 및 수량 관련 특성들을 비교 검토하고자, 시대별로 보급 면적이 넓었던 Japonica 6품종과 통일형 3품종에 대하여 건물 생산 특성인 광소멸계수(K), 광이용효율(RUE), 누적엽면적지수(LAD) 등과 수량 및 수량구성요소를 조사하였고, 각 특성들을 비교 검토하였다. 벼 군락의 K는 70년대 이전에 보급된 품종은 0.5이상으로 높은 값을 보였으나, 그 이후에 나온 Japonica 품종과 통일형 품종은 0.5보다 낮은 값을 보였다. 출수전 RUE는 japonica 품종 중에서는 팔달벼가 가장 낮았고, 조동지와 낙동벼가 높았으며, 통일형 품종 중에서는 밀양23호가 유의하게 낮았으나 품종육성연대에 따른 일정한 변화경향은 없었다. 한편 등숙기 RUE는 품종간에 유의적인 차이가 없었다. LAD는 품종간에 유의적인 차이가 있었는데, 최근에 육성된 품종일수록 LAD가 큰 경향이었다. 출수기까지의 LAD는 출수기 건물중과 유의한 상관이 인정되지 않았으나, 출수 후 LAD 및 전 생육기간의 LAD는 등숙기 건물생산량 및 수확기 건물중과 각각 유의한 정의 상관이 있었다. 출수기 및 수확기 건물중은 품종간에 유의적인 차이는 없었으나 통일계 품종의 경우는 최근에 육성된 품종일수록 높은 경향이었다. 수량은 자포니카 품종의 경우 1900년대 이전 품종인 조동지만이 유의하게 수량이 낮았으며, 그 이후에 육성된 japonica 품종 간에는 수량의 차이는 없었다. 통일형 품종은 최근에 육성된 품종일수록 수량이 높은 경향이었다, 수량은 단위면적당 영화수와 유의한 정의 상관관계가 있었는데 통일계 품종은 최근에 육성된 품종일수록 단위면적당 영화수가 많았다. 이상의 결과를 요약하면 japonica 품종의 경우 육성보급 연대에 따른 건물생산 특성인 K, RUE 및 LAD의 일정한 변화 경향이 없었으나, 통일계 품종의 경우는 최근에 육성된 품종일수록 수량이 증가하였는데, 이는 영화수 증대에 따른 sink size 증대와 더불어 LAD증대에 따른 건물생산성 증대에 기인하는 것이었다.

• 패션비즈니스
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• 제17권6호
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• pp.60-75
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• 2013

This study examined the categories and contents of technology that is recently influencing the fashion design. For this, the cases of global companies integrating fashion design and technology were examined, and the types of technology integration studies within the field of fashion design were analyzed through the trend of fashion-technology integration in domestic academic circles released since 2000. According to the case of global companies integrating fashion design and technology, various companies and fashion brands have released fashion products that are integrated with technology, and such integrations are developing up to the field of fashion shows and displays in addition to fashion products. The analysis of studies related with fashion and technology in the design field showed that domestic studies on fashion-technology integration were manifested as the types that applied various technologies to the fashion design. Such types were categorized into the studies that applied light-emitting technology, studies that focused on the integration of interaction and textile design, studies that applied response-perception, studies that used attached electronic devices, and studies that used autogenic bacteria. The fashion has less negative impact on body and environment compared with other areas, and therefore, is the best area for the experiments in IT, bio, and electronics areas and for the integration of fashion and technology. Moreover, studies on fashion that suggest the capability in developing and industrializing cases through the collaboration with other fields such as IT, bio, and electronics shall continue.

• 한국농공학회논문집
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• 제55권3호
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• pp.51-62
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• 2013

The importance of environmental water has been risen in terms of river ecosystem soundness with preventing stream flow depletion in rural area, while enlarging agricultural reservoir project is conducted under the 4 main river restoration project for supplying more water to 4 main rivers. The aim of this study was to estimate the amount of environmental water release and analyze the release pattern during non-irrigation season in enlarged agricultural reservoirs. The 4 reservoirs (Dansan, Samga, Geumbong, Changpyeong) located on the upper region of Nakdong river were simulated applying the operation rule which was determined by release criteria curves. The simulated results indicated that the more environmental water could be released than the spillway release and continuous release was achieved with smaller range of fluctuation. In case of Changpyeong reservoir, average 506.0 thousand $m^3$ environmental water could be released on Feb., and it was about twice as much as the spillway release before the enlargement, and also, the 18 thousand $m^3$/day environmental water could be supplied to a stream consistently after enlargement. From the results, it was expected that the additional environmental water release will improve stream water flow during dry season in terms of quantity and quality of water.

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.1939-1950
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• 2019

The MELCOR code useful for a plant-specific hydrogen risk analysis has inevitable limitations in prediction of a turbulent flow of a hydrogen mixture. To investigate the accuracy of the hydrogen risk analysis by the MELCOR code, results for the turbulent gas behavior at pipe rupture accident were compared with CFX results which were verified by the American National Standard Institute (ANSI) model. The postulated accident scenario was selected to be surge line failure induced by station blackout of an Optimized Power Reactor 1000 MWe (OPR1000). When the surge line failure occurred, the flow out of the surgeline was strongly turbulent, from which the MELCOR code predicted that a substantial amount of hydrogen could be released. Nevertheless, the results indicated nonflammable mixtures owing to the high steam concentration released before the failure. On the other hand, the CFX code solving the three-dimensional fluid dynamics by incorporating the turbulence closure model predicted that the flammable area continuously existed at the jet interface even in the rising hydrogen mixtures. In conclusion, this study confirmed that the MELCOR code, which has limitations in turbulence analysis, could underestimate the existence of local combustible gas at pipe rupture accident. This clear comparison between two codes can contribute to establishing a guideline for computational hydrogen risk analysis.

• 대한조선학회논문집
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• 제43권2호
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• pp.236-245
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• 2006

The ventilation performance for the various venting duct arrays has been experimentally compared in the scaled model of the container hold. Most container ships have the ventilation duct system to remove effectively the condensing heat released from container refrigerator. The existing duct system is vertically installed and basically has the number of duct as many as the columns of reefer container stack. In this study, to make up for the weak points having stagnantly hot legions in the centered area of container hold for the present system, the horizontal upward jotting duct system was proposed and proved by temperature rising tests on the scaled model. In this paper, the expected flow regimes and the thermal and hydrodynamic analogies as well as the measured temperature distributions in a hold for various duct types and heat released rates are deeply discussed.

• 수산해양교육연구
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• 제18권3호
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• pp.261-271
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• 2006

The present study is aimed at evaluating the economic effectiveness of Abalone, haliotis discus hanai Releasing Project(ARP) conducted in the fishing ground owned by a fishing village in Ulsan, Korea. The results were summarized as follows: First, an average ratio of released abalones in the total landing after releasing is shown to be 85.0%. Second, the recapture rate of released abalones is 46.8%, exceeding the recapture rate of BEP(Break-Even-Point), 22.9%. Third, it is evaluated that total economic effectiveness of the ARP is 6.7-6.8 times, net effectiveness is 2.2-2.3 times, and the NPV(Net Present Value) discounted by a 8% interest rate is 474, 635 thousand wons, indicating the project is profitable. Considerable parts of the positive results on the ARP are based on some beneficial conditions, including the selection of favorable releasing sites, best self-regulation system of a fishing village for preservation of seaweed facilities and continued activities for protecting small abalones and their rearing. These results imply that the success of the ARP would be primarily dependent upon the selection of releasing site and effective management system after releasing.

• 한국통신학회논문지
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• 제22권5호
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• pp.1075-1082
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• 1997

In this paper, we propose a channel assignment scheme for reducing call blocking rate in a base station(BS) of DS-CDMA cellular systems. The proposed scheme can e applied to the case where the capacity of reverse radio link is enough, but not are the available traffic channels performing the digital modulation and demodulation functions between a mobile station and the base station. The proposed scheme takes advantage of the feature of soft handoff in which a mobile station keeps its communication link even if one of the two communication links is released. The scheme estimates the mean and variance of the received power level measured at the base station before assigning a traffic channel for a new call request. The BS makes decision based on the estimated balues whether the new call request will be accepted or not. If it is decided that the capacity of reverse radio link is enough, but all traffic channels are not available, then the BS increases the soft handoff parameter T_DROP to release the traffic channels of mobile stations loactedin soft handoff area. The BS assigns the released traffic channel to anew call or a handoff call. The performance of the proposed channel assignment scheme is evaluated by computer simulation. The results show that the call blocking rate for new calls and handoff calls is reduced.

• 방사선산업학회지
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• 제6권1호
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• pp.41-47
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• 2012

A field tracer experiment using a radioisotope was conducted to analyze the transport and dispersion characteristics of pollutants in the coastal area near a Wolsung. A rod float including GPS was released to track the paths of radioisotope. NaI detector was installed to measure the released radioisotope from the boat, and measurements were performed with the real time. The measured tracer data by a field experiment can be used as the basic data for understanding the transport characteristics of pollutants and verifying numerical models near the offshore.

• 한국패류학회지
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• 제26권1호
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• pp.97-105
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• 2010

제주 항 내에 서식하는 대수리 Thais clavigera를 조직학적 방법을 이용하여 1998년 3월부터 1999년 2월까지 생식소 발달과 생식주기 그리고 imposex 현상에 대해 조사하였다. 조직학적 관찰 결과, 배우자형성은 암,수 모두 10월에 처음 시작 되었고, 성숙한 알들은 주로 5월에서부터 7월 사이에 관찰되었다. 생식소단면적 지수 역시 알이 성숙하는 5월과 7월 사이 급격히 증가하였으며, 8월에 급격히 낮아져, 7월과 8월 사이에 집중적인 산란이 있었던 것으로 사료되었다. 유기주석화합물에 의한 imposex 현상의 진행 정도를 나타내는 RPSI는 월 평균 59.5-173.4%로 다른 지역에 비하여 비교적 높게 나타났으며, 이는 제주 항 내의 유기주석화합물에 의한 것으로 추정되었다.

• 한국통신학회논문지
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• 제30권9B호
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• pp.581-590
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• 2005

근거리망의 이더넷 기술과 도시망에 적합한 링 토폴로지를 결합하여 성능이 뛰어나고 고장에 강하며 근거리망과의 호환성을 유지하는 RPR(Resilient Packet Ring)이 도시망의 핵심기술로 뜨오르고 있다. IEEE 802.11에서 RPR에 대한 표준화가 완성중인데, 공평한 대역폭의 사용을 보장하기 위해 설계된 RPR의 공정성 제어기법이 비대칭 과부하 트래픽 환경에서 성능저하를 초래하는 문제점을 안고 있다. 본 논문에서는 이러한 성능저하 문제를 해결하기 위해 체증해제 통보 기반의 공정성 제어방식을 제안하고 이의 성능을 분석한다. 제안된 방식에서는 체증 발생노드가 자신의 체증해제 여부를 판단하여 상단노드로 통보하면 상단노드는 하단노드의 체증을 해소하기 위해 제한하였던 자신의 트래픽 전송속도를 즉시 원래의 속도로 복구한다. 제안된 방식은 종래의 공정성 제어방식과 호환성을 가지며 체증해제 임계값의 선택에 의해 성능저하의 정도를 임의대로 조정할 수 있다.