• 제목/요약/키워드: selection efficiency

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On-demand Allocation of Multiple Mutual-compensating Resources in Wireless Downlinks: a Multi-server Case

  • Han, Han;Xu, Yuhua;Huang, Qinfei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권3호
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    • pp.921-940
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    • 2015
  • In this paper, we investigate the multi-resource allocation problem, a unique feature of which is that the multiple resources can compensate each other while achieving the desired system performance. In particular, power and time allocations are jointly optimized with the target of energy efficiency under the resource-limited constraints. Different from previous studies on the power-time tradeoff, we consider a multi-server case where the concurrent serving users are quantitatively restricted. Therefore user selection is investigated accompanying the resource allocation, making the power-time tradeoff occur not only between the users in the same server but also in different servers. The complex multivariate optimization problem can be modeled as a variant of 2-Dimension Bin Packing Problem (V2D-BPP), which is a joint non-linear and integer programming problem. Though we use state decomposition model to transform it into a convex optimization problem, the variables are still coupled. Therefore, we propose an Iterative Dual Optimization (IDO) algorithm to obtain its optimal solution. Simulations show that the joint multi-resource allocation algorithm outperforms two existing non-joint algorithms from the perspective of energy efficiency.

원위치 토양세척 공정의 효율향상을 위한 세제선정과 운전기법 (Selection of Surfactant and Operation Scheme for Improved Efficiency of In-situ Soil Flushing Process)

  • 손봉호;임봉수;어성욱;이병호
    • 한국물환경학회지
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    • 제22권5호
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    • pp.824-830
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    • 2006
  • Several tests were conducted to optimize the design parameters of ln-situ soil flushing processes for diesel contaminated soil. According to the batch extraction test for three anionic surfactants evaluation, Calgonit limiting bubble occurrence was selected for its higher oil cleaning efficiency. After optimum surfactant selection, there were many sets of column flushing test. Over 70% of BTEX was removed in this surfactant dose with 400% of soil volume. In the case of no surfactant addition flushing in column, so called "blank flushing test", BTEX removal rate was 64%. But when we reused the effluent for the cleaning solution, the removal rate was decreased to 46.9%. This result showed reabsorption of oil occurred on the soil. With the addition of Calgonit solution to the diesel contaminated column, BTEX was removed up to 98.9% during the first flushing and 99.4% for the second recirculation flushing. In microcosm tests, diesel contaminated soils were cleaned by both surfactant flushing and biological activities. In anoxic condition, nitrate was used as an electron acceptor while the surfactant and the oil were used an electron donor. BTEX removal efficiency could be achieved up to 80% by biological degradation.

기능저하 저수지 선정을 위한 다기준 의사결정기법 적용성 연구 (Study on Applicability of Multi-Criteria Decision Making Technique for Malfunctioning Reservoir Selection)

  • 심현철;최경숙
    • 한국농공학회논문집
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    • 제59권3호
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    • pp.11-19
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    • 2017
  • The decision-making process is the act of finding the best solution among various alternatives through comparison between various criteria based on objectives of the project, evaluation standard, and conditions. However, in practice it is not easy to simply decide the optimum decision, especially for selecting malfunctioning reservoirs because no systematic evaluation criteria or standard assessment process are available. Therefore, this study adopted AHP method, which is a MCDM (multi-criteria decision making technique) to identify the malfunctioning reservoirs for efficient management of reservoirs. Important criteria of the selection of malfunctioning reservoirs and priority weights of each criteria were determined based on results of expert's survey under a stepwise hierarchical approach. The most important factor for the decision of malfunctioning reservoirs was obtained as Reservoir efficiency among the selected criteria including Reservoir efficiency decrease, Disaster Risk, Reservoir efficiency, Available water storage, Future water demand, Resident Needs. The AHP technique was applied on 11 reservoirs in Andong region to verify its applicability. Scoring method was applied for the comparison with the results of AHP method.

도서관의 공간사용 특성에 따른 냉난방설비 리모델링의 경제성 평가 (Energy Efficiency Evaluation of Heating and Cooling Systems as Space Program in Renovated Library)

  • 박강현;차정훈;김수민;박경원
    • 설비공학논문집
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    • 제24권3호
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    • pp.205-211
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    • 2012
  • Unlike the previous approaches, we analyzed for economic efficiency of renewed heating and cooling systems as the characteristics of space. The purpose of this study is to analysis the energy consumption and economical efficiency of absorption chillers and EHP systems in renovated library. It is important that equipment selection should be considering energy cost as well as space program. In recently, many EHP systems were installed in the building for reducing the energy cost and for seeking the convenience of individual control. In contrast, though absorption chillers have the disadvantage of a central control, absorption chillers are appropriate for the conditions of the library that needs simultaneous operation. The results by payback period method, show that selection of heating and cooling systems should be consider for space program and the characteristics of space.

피조개 항망의 어획선택성에 관한 연구 (A Study on the Catching Selectivity of the Ark Shell(Scapharca Broughtonii)Dredge)

  • 조봉곤
    • 수산해양기술연구
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    • 제35권4호
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    • pp.366-376
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    • 1999
  • In order to examine the catching selectivity of the ark shell(Scapharca broughtonii) dredge, the various factors affecting the selective action of the dredge are analyzed, and the probabilities of the ark shell not shifting through the gaps between the teeth, and the mesh of the netting bag, are calculated for the various shell lengths, using the relation between the posture and the length when the shell passes through these parts.Considering that the probability of making catch is the product of the both probabilities described above, and that this probability is proportional to the relative catching efficiency, the selectivity curves for the ark shell dredge were estimated for various gaps between the teeth and for the various mesh sizes of the netting bag. The obtained results are summarized as follows :1. The ratios of the shell length of ark shell to the distance between teeth indicating the relative catching efficiency of 0%, 50, 100% respectively were 1.0, 1.26~1.28, 1.47~1.44, and that the selection ranges of selective shell length by the distance between teeth were 0.47~0.44, where the distances between teeth were 3.2cm, 3.6cm, 4.0cm, 4.4cm and 4.8cm. 2. The ratios of the shell length of ark shell to the mesh size indicating the relative catching efficiency of 0%, 50%, 100% respectively were 0.67, 0.84, 0.97 and that the selection range of shell length for catching, that in the range of selective shell length by the mesh size was 0.31, where the distance of 4.0cm between teeth, mesh size of 6.0 cm and the smaller mesh angle of $60^{\circ}$3. Where the distance between teeth is 4.0 cm and the smaller mesh angle is $60^{\circ}$, the selection range of shell length for catching of the ark shell dredge is decreased according to the mesh size, and it is minimized by 0.20 in the mesh size of 9.0~10.0 cm, but increased in the mesh size of over 11.0 cm. 4. Where the distance between teeth is 4.0 cm, the selective action by the mesh size of netting bag is begun with the mesh size of over 10.0 cm.

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위상차 클럭 기반 NoC 용 동기회로 설계 (Mesochronous Clock Based Synchronizer Design for NoC)

  • 김강철
    • 한국전자통신학회논문지
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    • 제10권10호
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    • pp.1123-1130
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    • 2015
  • NoC는 SoC의 IP 코어들 사이에서 통신하는 시스템으로 기존의 버스 시스템이나 크로스바 상호연결 시스템보다 월등히 향상된 성능을 제공한다. 그러나 NoC의 송신부와 수신부 사이에서 데이터 이동 시에 송신부와 수신부 사이에 발생하는 불안정 상태(metastability)는 극복하기 위하여 동기회로가 필요하다. 본 논문에서는 신호 영역 발생기, 선택 신호 발생기와 데이터 버퍼로 구성된 새로운 위상차 동기회로를 설계하였다. 불안정 상태가 없는 선택구간을 구하기 위하여 전송된 클럭을 지연하는 회로가 사용되며, 전송클럭과 지역 클럭을 비교하여 선택신호를 발생한다. 제안된 위상차 동기회로는 선택신호 값에 의하여 지역클럭의 상승 또는 하강 모서리 중의 하나를 선택하여 불안정 상태를 제거한다. 모의실험 결과는 제안된 위상차 동기회로가 전송된 클럭과 지역 클럭의 어떤 위상차에서도 잘 동작하는 것을 보여 주었다.

자질 선정 기준과 가중치 할당 방식간의 관계를 고려한 문서 자동분류의 개선에 대한 연구 (An Empirical Study on Improving the Performance of Text Categorization Considering the Relationships between Feature Selection Criteria and Weighting Methods)

  • 이재윤
    • 한국문헌정보학회지
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    • 제39권2호
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    • pp.123-146
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    • 2005
  • 이 연구에서는 문서 자동분류에서 분류자질 선정과 가중치 할당을 위해서 일관된 전략을 채택하여 kNN 분류기의 성능을 향상시킬 수 있는 방안을 모색하였다. 문서 자동 분류에서 분류자질 선정 방식과 자질 가중치 할당 방식은 자동분류 알고리즘과 함께 분류성능을 좌우하는 중요한 요소이다. 기존 연구에서는 이 두 방식을 결정할 때 상반된 전략을 사용해왔다. 이 연구에서는 색인파일 저장공간과 실행시간에 따른 분류성능을 기준으로 분류자질 선정 결과를 평가해서 기존 연구와 다른 결과를 얻었다. 상호정보량과 같은 저빈도 자질 선호 기준이나 심지어는 역문헌빈도를 이용해서 분류 자질을 선정하는 것이 kNN 분류기의 분류 효과와 효율 면에서 바람직한 것으로 나타났다. 자질 선정기준으로 저빈도 자질 선호 척도를 자질 선정 및 자질 가중치 할당에 일관되게 이용한 결과 분류성능의 저하 없이 kNN 분류기의 처리 속도를 약 3배에서 5배정도 향상시킬 수 있었다.

핵심역량에 기초한 A 통신사의 선발시스템 사례연구 (Telecommunication Company A's Selection System Case Based on the Core Competencies)

  • 구정호;이광희;이병진
    • 산업경영시스템학회지
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    • 제37권1호
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    • pp.9-25
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    • 2014
  • It is very important to select the best employees who are suitable for their jobs and duties as considering the efficiency and productivity of the firms' performance. As a result, many kinds of selection methodologies and systems have been developed. Among them is the selection system based on the core competencies which is known as the superior selection systems that can increase the predictive validity who is the right people, compared to the traditional selection system based on the job analysis. Hence, the former has been focused in the complex business situation in recent years. In this case study, we examine the selection system case based on the core competencies of OSS team in Company A, which is one of the largest telecommunication firms and we suggest the implications. According to the results of this case study, defining the core competencies of the job and selecting the right people who had the related competencies not only decreased the turnover rate of OSS team in Company A, but also increased the employees' loyalty and satisfaction for the organizations. This study will be a benchmark to other departments that don't use competency selection system of Company A as well as the firms that want to adapt the selection system based on the core competencies. Also, this case study has a contribution that shows us an alternative model how can the firms identify and select the best right employees.

Validation of selection accuracy for the total number of piglets born in Landrace pigs using genomic selection

  • Oh, Jae-Don;Na, Chong-Sam;Park, Kyung-Do
    • Asian-Australasian Journal of Animal Sciences
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    • 제30권2호
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    • pp.149-153
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    • 2017
  • Objective: This study was to determine the relationship between estimated breeding value and phenotype information after farrowing when juvenile selection was made in candidate pigs without phenotype information. Methods: After collecting phenotypic and genomic information for the total number of piglets born by Landrace pigs, selection accuracy between genomic breeding value estimates using genomic information and breeding value estimates of best linear unbiased prediction (BLUP) using conventional pedigree information were compared. Results: Genetic standard deviation (${\sigma}_a$) for the total number of piglets born was 0.91. Since the total number of piglets born for candidate pigs was unknown, the accuracy of the breeding value estimated from pedigree information was 0.080. When genomic information was used, the accuracy of the breeding value was 0.216. Assuming that the replacement rate of sows per year is 100% and generation interval is 1 year, genetic gain per year is 0.346 head when genomic information is used. It is 0.128 when BLUP is used. Conclusion: Genetic gain estimated from single step best linear unbiased prediction (ssBLUP) method is by 2.7 times higher than that the one estimated from BLUP method, i.e., 270% more improvement in efficiency.