• 대한공간정보학회지
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• 제20권1호
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• pp.13-20
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• 2012

본 연구의 목적은 유역 하천망의 발달에 따른 수문응답함수의 변화양상 분석에 있다. 이를 위한 대상유역은 보청천의 탄부수위표를 출구로 하는 소유역을 선정하였다. 적용된 하천망은 Strhler 차수분류법에 의해 구성된 하천망과 유역 내 모든 격자가 하천 또는 지표면으로 구성된 경우로 총 10가지로 구성하였다. 각각의 경우에 대해 대상유역 내 모든 격자의 지표면과 하천 배수경로 길이를 산정하였으며 Nash 모형을 이용하여 수문응답함수를 결정하였다. 분석결과 하천망이 발달함에 따라 수문응답함수의 첨두유량은 크게 나타나며, 첨두시간은 작아지는 양상을 보였다. 또한 응답함수의 통계적 특성을 살펴 본 결과 하천망의 발달에 따라 유하시간의 평균(지체시간)과 분산이 지수적으로 감소함을 알 수 있었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.213-216
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• 2000

In this paper, we propose a new scheme which improves the IP address lookup time. The new scheme is composed of two core technologies, named the prefix alignment and the prefix distance ordering. Now, as the Internet is being used commonly by improving the data transmission capacity, the need for enlarging the bandwidth of the Internet is on the rise. IP address lookup performance problem is an important obstacle in the router executing high speed packet forwarding. This results from the fact that the prefixes routing table is composed of and the traffic being processed in unit time are largely on the increase. The proposed lookup scheme is divided into two parts in technology, the one is the algorithm forming a routing database(routing table), the other is the lookup procedure in the actual packet processing.

• 디지털융복합연구
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• 제4권2호
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• pp.97-108
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• 2006

The purpose of this study is to generate a proper regulation improvement direction of the public If project contract law through the current four contract methods and three methods of the awarding party of a contract method. The research method for this paper is derived from the written materials of the present public IT project contract law. Two problems have been processed in order to produce the results: the current contract methods and the awarding party of a contract method. The current contract methods consist of a competition contract, a private contract, and a supply methodology contract, The methods of the awarding party of a contract display a qualified evaluation regulation, the 2nd step competition bid, a standard cost separation tender, and a contract by a negotiation. The results exhibit that the general competition contract consists of four improvement items. The contract by a negotiation contains five improvement items. The group private contract has one improvement item. And the private contract includes one improvement item. These results implicate that the current public IT project contract law demands better improvement work for the ubiquitous Korea.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2006년도 춘계학술대회
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• pp.319-353
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• 2006

The purpose of this study is to generate a proper regulation improvement direction of the public IT project contract law through the current four contract methods and three methods of the awarding party of a contract method. The research method for this paper is derived from the written materials of the present public IT project contract law. Two problems have been processed in order to produce the results: the current contract methods and the awarding party of a contract method. The current contract methods consist of a competition contract, a private contract, and a supply methodology contract. The methods of the awarding party of a contract display a qualified evaluation regulation, the 2nd step competition bid, a standard cost separation tender, and a contract by a negotiation. The results exhibit that the general competition contract consists of four improvement items. The contract by a negotiation contains five improvement items. The group private contract has one improvement item. And the private contract includes one improvement item. These results implicate that the current public IT project contract law demands better improvement work for the ubiquitous Korea.

• 전자공학회논문지
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• 제50권8호
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• pp.61-66
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• 2013

본 논문에서는 채널부호화 다중 안테나 시스템에서 공간다중화 전송된 신호들을 효과적으로 복조하기 위한 저연산 연판정 복조 다중 안테나 반복검출 기법을 제시한다. 반복 검출기법의 경우 우수한 성능에도 불구하고 연산량의 복잡성으로 수신단에 높은 복잡도를 요청하게 된다. 이러한 복잡도 감소를 위해 차원감소 소프트 검출 기법 (DRSD)과 모든 순서 순차적 간섭 제거(AOSIC) 기법을 사용한다. 이 기법의 경우 기존 기법들에 비해 반복검출 기법의 연산량의 복잡성을 줄일 수 있으며 향상된 성능을 얻을 수 있다.

• 대한전자공학회논문지TC
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• 제44권2호
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• pp.6-14
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• 2007

본 논문에서는 V-BLAST (Vertical-Bell-lab Layered Space Time) 복호 알고리즘의 ordering과 slicing 과정에 MAP(Maximum A Posteriori) 디코더의 외부 정보 (extrinsic information)를 이용한 최적의 터보 부호화된 (Optimal Turbo Coded) V-BLAST 적응 변조 시스템을 제안 후 성능을 관찰한다. 외부정보는 ordering과 slicing에 사전 확률 (a priori probability) 로서 사용되며 시스템 복호 과정은 주 반복 (Main Iteration) 및 부 반복 (Sub Iteration) 과정으로 이루어진다. 채널 상태에 따라 변조 방식을 달리하는 적응 변조 시스템을 기존의 터보 부호화 (Turbo Coding) 된 V-BLAST 시스템과 최적의 터보 부호화된 V-BLAST 시스템에 각각 적용하고 전송률 (throughput) 을 비교하여 제안된 시스템을 적용할 경우 어느 정도의 성능 개선이 있는가를 살펴본다. 또한, 제안된 시스템에 선택적 전송 다이버시티 (STD : Selection Transmit Diversity) 기법을 적용한 후 성능의 향상을 관찰한다. 모의 실험결과, 적응 변조 시스템에서 최적의 터보 부호화된 V-BLAST 기법을 적용한 경우가 기존의 터보 부호화된 V-BLAST 기법을 적용한 경우에 비하여 11 dB의 SNR (Signal to Noise Ratio) 영역에서 최대 약 350 kbps의 전송률 향상이 나타났다. 특히, 제안된 시스템에 선택적 전송 다이버시티가 적용된 경우에는 송수신 안테나가 각각 2개인 기존의 터보 부호화된 V-BLAST 기법을 적용한 시스템의 경우에 비하여 같은 SNR 영역에서 최대 약 1.77 Mbps의 전송률이 개선됨을 보였다.

• 한국국방경영분석학회지
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• 제23권2호
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• pp.72-84
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• 1997

In this paper, we consider an economic order quantity(EOQ) and an optimal discount pricing policy for the monopsony related to the weapon system acquisition. In the monopsony case, a buyer wishes to maximize the profit. However, a seller wants to minimize the total inventory related cost since a buyer can determine the purchase price for the product. We develop a generalized version of EOQ model for the monopsony, including one seller-one buyer model and two seller-one buyer model. A model of buyer reaction to any given pricing scheme is developed to show that there exits a unified pricing policy which motivates the buyer to increase its ordering quantity per order, thereby reducing the joint(buyer and seller) ordering and holding costs in the system.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.609-612
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• 2000

Job-shop scheduling problem(JSSP) is one of the best-known machine scheduling problems and essentially an ordering problem. A new encoding scheme which always give a feasible schedule is presented, by which a schedule directly corresponds to an assigned-operation ordering string. It is initialized with G&T algorithm and improved using the developed genetic operator; APMX or BPMX crossover operator and mutation operator. and the problem of infeasibility in genetic generation is naturally overcome. Within the framework of the newly designed genetic algorithm, the NP-hard classical job-shop scheduling problem can be efficiently solved with high quality. Moreover the optimal solutions of the famous benchmarks, the Fisher and Thompson's 10${\times}$10 and 20${\times}$5 problems, are found.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.238-239
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• 2013

A system to efficiently utilize construction information has been in demand as a result of the changing society where information and knowledge leads to added value. Consequently, the government established a comprehensive information network system for construction industries to manage and utilize construction information which is the currently in use. However, this system is oriented toward management and business performance estimation for engineering and does not integrate a management system for design, construction technology, and construction engineering services. Therefore, this study proposes to develop object technology and management system of construction services and its evaluation to provide such information in real time.

• 한국멀티미디어학회논문지
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• 제11권6호
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• pp.796-806
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• 2008

This paper presents a blind video watermarking algorithm that has the robustness against spatial, temporal, and SNR scalability and transcoding for the copyright protection of video contents in heterogeneous multimedia service. The proposed process of watermark embedding and detecting is accomplished on base layer for considering spatial scalability. The watermark consists of the string and the ordering number of string for considering temporal scalability. Thus, each of frames has the bitstream of one character and a ordering number of its character. To robust against FGS, the proposed algorithm quantizes low and middle frequency coefficients in ROI region of each of frames and embeds its watermark bitstream into the specific bits of the quantized coefficients. Experimental results verified that the proposed algorithm satisfies the invisibility of watermark and also has the robustness against spatial scalability, temporal scalability and FGS.