• 노동경제논집
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• 제40권1호
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• pp.37-68
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• 2017

본 연구에서는 재정패널 자료를 이용하여 가계부채와 기혼여성의 노동공급 사이의 관계를 분석하였다. 이를 위해 가구의 이자비용 납부액 대비 가구금융부채 금액을 이용하여 가구의 유효이자율을 구축하였다. 금융부채가 없는 가구의 경우 Heckman Selection 모형을 적용하여 가구의 이자율을 추정하였다. 실증 분석결과 가구에서 부담하는 유효이자율이 상승하게 될 경우 기혼여성의 노동시장 참여가 확대된다는 것을 발견하였다. 이로부터 기준금리가 인상되는 상황에서 예상할 수 있는 부정적인 시나리오를 가구 노동공급 증가와 근로소득의 상승효과를 통해 일정 부분 상쇄할 수 있는 긍정적인 효과를 제시하고 있다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.27-30
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• 2003

서비스기반 경쟁효과를 호주 사례로 검토결과, 시내전화 시장은 재판매 도입으로 인해 Telstra의 시장점유율은 후발사업자들에 의해 약 13%를 정도 잠식되었고 시장평균 통화료는 인하되었다. 그러나 Telstra는 통화료 인하에 따른 수익보전을 위해 기본료를 14.5% 인상 조정 하였다. 사업자사전선택제의 장거리전화 및 국제시장 도입에 따라 장거리전화요금은 23.5%, 국제전화요금은 53%가 인하되었고 천이(Churn)자 수도 증가하였다. 이와 같이 서비스기반 경쟁은 장거리전화 및 국제전화 시장에서의 효율적 결과를 가져왔다. 그러나 LM통화 시장은 사업자사전선택 실시는 13.4%의 통화료인하를 가져왔으나 과금구조의 복잡성, 효율적 경쟁극대를 위한 과대비용 전망, 기술적 장벽, 소비자의 왜면으로 인해 효과가 미미한 것으로 나타났다.

• 한국유체기계학회 논문집
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• 제4권4호
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• pp.22-27
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• 2001

The pump/motor selection program for optimized selection of regional water supply facilities was developed based on a flowchart compiled from basic operational data, total head requirement, initial pump/motor specification selection etc. This program was developed in Visual Basic. The program accepts, as in the flowchart, operational requirements of pumps and other system requirements, and calculates specific speed based on flow rate, total head and rotational speed. Then the calculated specific speed is used to select pump types and speed prior to determining likelihood of cavitation occurring at the calculated NPSH. Power requirement is then calculated for safe operation of pump to assist final pump selection. Test results of the program match very closely to the design values of Paldang intake pump station(3rd stage) proving that the program can be used as an effective and practical aid for designing new regional water supply systems.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.171-176
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• 2001

The Pump/Motor Selection Program for optimized selection of regional water supply facilities was developed based on a flowchart compiled from basic operational data, total head requirement, initial pump/motor specification selection etc.. This program was developed in Visual Basic. The program accepts, as in the flowchart, operational requirements of pumps and other system requirements and calculates specific speed based on flow rate, total head and na Then the calculated specific speed is used to select pump types and rpm Prior to determining likelihood of cavitation occurring at the calculated NPSH. Power requirement is then calculated for safe operation of pump to assist final pump selection. Test results of the program matches very closely to the design values of Paldang intake pump station(3rd stage) proving that the program can be used as an effective and practical aid for designing new regional water supply systems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권3호
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• pp.1111-1130
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• 2016

Cooperative communications can significantly improve the wireless transmission performance with the help of relay nodes. In cooperative communication networks, relay selection and power allocation are two key issues. In this paper, we propose a relay selection and power allocation scheme RS-PA-PSACO (Relay Selection-Power Allocation-Particle Swarm Ant Colony Optimization) based on PSACO (Particle Swarm Ant Colony Optimization) algorithm. This scheme can effectively reduce the computational complexity and select the optimal relay nodes. As one of the swarm intelligence algorithms, PSACO which combined both PSO (Particle Swarm Optimization) and ACO (Ant Colony Optimization) algorithms is effective to solve non-linear optimization problems through a fast global search at a low cost. The proposed RS-PA-PSACO algorithm can simultaneously obtain the optimal solutions of relay selection and power allocation to minimize the SER (Symbol Error Rate) with a fixed total power constraint both in AF (Amplify and Forward) and DF (Decode and Forward) modes. Simulation results show that the proposed scheme improves the system performance significantly both in reliability and power efficiency at a low complexity.

• 한국멀티미디어학회논문지
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• 제9권12호
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• pp.1560-1571
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• 2006

In order to transmit multimedia streams over the network with a timely changing channel bandwidth such as Internet, scalable video coding schemes have been studied to represent video in flexible bitstream. Much research has been made on how to represent encoded media(such as video) bitstream in scalable ways. In this paper, rte propose an optimal selection of the objects for MPEG-4 bitstream adaptation to meet a given constraint. We adopt a multiple choice knapsack problem with multi-step selection for the MPEG-4 objects with different bit-rate scaling levels in the MPEG-4 bitstream. The bitstream adaptation based on the optimal selection result is then to fetch the necessary parts of the MPEG-4 bitstream to constitute an adapted version of the original MPEG-4 binary resource. The experiment results show that the optimal selection of MPEG-4 objects for a given constraint can promisingly be made which meets the given constraint.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권10호
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• pp.5079-5099
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• 2018

Regarding to the huge number of connections and the large flow of data on the Internet, Intrusion Detection System (IDS) has a difficulty to detect attacks. Moreover, irrelevant and redundant features influence on the quality of IDS precisely on the detection rate and processing cost. Feature Selection (FS) is the important technique, which gives the issue for enhancing the performance of detection. There are different works have been proposed, but a map for understanding and constructing a state of the FS in IDS is still need more investigation. In this paper, we introduce a survey of feature selection algorithms for intrusion detection system. We describe the well-known approaches that have been proposed in FS for IDS. Furthermore, we provide a classification with a comparative study between different contribution according to their techniques and results. We identify a new taxonomy for future trends and existing challenges.

• 대한산업공학회지
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• 제36권3호
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• pp.164-175
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• 2010

In this study, we developed a genetic algorithm to find a near optimal solution of concurrent spare parts selection for the operational time period with limited information of weapon systems purchased from overseas. Through the analysis of time profiles related with system operations, we first define the optimization goal which maintains the expected system operating rate under the budget restrictions, and the number of failures and the lead time for each spare part are used to calculate the estimated total down time of the system. The genetic algorithm for CSP selection shows that the objective function minimizes the estimated total down time of systems with satisfying the restrictions. The method provided by this study can be applied to the generalized model of CSP selection for the systems purchased from overseas without provision of their full structure and adequate information.

• Journal of information and communication convergence engineering
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• 제10권3호
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• pp.215-219
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• 2012

This paper applies transmit antenna selection algorithms to spatial-temporal combining-based spatial multiplexing (SM) ultra-wideband (UWB) systems. The employed criterion is based on the largest minimum output signal-to-noise ratio of the multiplexed streams. It is shown via simulations that the bit error rate (BER) performance of the SM UWB systems based on the two-dimensional Rake receiver is significantly improved by antenna diversity through transmit antenna selection on a log-normal multipath fading channel. When the transmit antenna diversity through antenna selection is exploited in the SM UWB systems, the BER performance of the spatial-temporal combining-based zero-forcing (ZF) receiver is also compared with that of the ZF detector followed by the Rake receiver.

• 한국정보통신학회논문지
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• 제15권3호
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• pp.561-566
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• 2011

EPCglocal Class-1 Gen-2 RFID 시스템에서는 응답 슬롯의 상태에 따라 다음 질의 라운드의 슬롯 카운트 크기를 결정하는 슬롯 카운트 선택 알고리즘을 제안하였다. Gen-2 RFID 시스템의 슬롯 카운트 선택 알고리즘에서는 슬롯 카운트의 크기를 일정한 값을 가진 가중치 C만큼 증가 또는 감소시킨다. 슬롯의 상태와 무관하게 가중치 C의 값을 동일하게 적용함으로 인하여 알고리즘이 단순한 장점이 있는 반면, 최적의 슬롯 카운트 크기를 유지하기 어려운 단점이 있다. 따라서 본 논문에서는 태그의 응답 결과에 따라 가중치 C의 값을 서로 다르게 적용한 적응적 슬롯 카운트 선택 알고리즘을 제안하고, 이에 대한 성능을 분석한다. 시뮬레이션을 통한 성능분석의 결과, 제안한 알고리즘은 충돌률이 Wang이 제안한 기법과 Gen-2 기법에 비하여 각각 42% 및 65% 정도 낮으므로 태그 식별 시간이 짧음을 알 수 있었다.