• 제목/요약/키워드: Large-Scale Problem

검색결과 951건 처리시간 0.027초

양돈 농장 규모에 따른 HACCP 적용 목적, 효과, 문제점 분석 (Analysis of Purpose, Effectiveness and Problem of HACCP System Implementation according to Scales of Swine Farm)

  • 남인식
    • 한국유기농업학회지
    • /
    • 제25권3호
    • /
    • pp.643-651
    • /
    • 2017
  • 본 연구는 HACCP 제도를 적용하고 있는 소규모, 중규모, 대규모 양돈농장의 HACCP 제도 도입 목적, 효과, 그리고 문제점 등을 비교분석하기 위한 목적으로 실시하였다. 소규모와 중규모 양돈농장은 HACCP 도입 목적의 1순위를 정부의 예산을 지원받기 위함이라고 하였으나 대규모 농장은 농장의 경쟁력 향상이라고 답하였다. HACCP 적용 효과는 소규모 농장의 경우 체계적인 농장관리를 1순위로 응답하였으나 중규모와 대규모 농장은 농장의 위생관리 수준 향상이라고 답하였다. 아울러 HACCP 적용에 따라 발생되는 가장 큰 문제점으로는 직원의 의식향상의 어려움(소규모 농장)과 HACCP 도입에 따른 기록관리(중규모, 대규모 농장)인 것으로 조사되었다. 이러한 문제점을 개선하기 위해서는 양돈농장 HACCP 평가항목 수의 조정과 종업원을 대상으로 HACCP 교육을 실시할 필요성이 있을 것으로 판단된다.

공종별 특성을 고려한 대·소규모 공사의 실적공사비 비교 및 보정방안 (A Compensation Method and Comparative Analysis of Historical Unit Price Considering Work Types for Large and Small-Scale Projects)

  • 홍성호;이동욱
    • 대한토목학회논문집
    • /
    • 제34권1호
    • /
    • pp.293-303
    • /
    • 2014
  • 현재 실적공사비 단가는 한국건설기술연구원에 의해 발표되고 있으며, 대규모 공사에서 수집된 공사비 자료를 분석하여 작성되고 있다. 따라서 소규모 공사의 경우 현행 실적공사비 단가를 적용함에 있어 불합리한 문제점이 발생하고 있다. 이러한 문제점을 분석하기 위해, 본 연구에서는 대 소규모 토목, 건축, 기계설비공사에 대한 실적공사비를 상호 비교하였다. 그 결과, 소규모 공사의 실적공사비는 대규모 공사에 비해 평균적으로 26.6%가 높음을 확인할 수 있었다. 한편, 노무비에 의한 대 소규모 공사의 실적공사비 차이는 18.4%이고, 재료비 경비에 의한 차이는 8.18%인 것으로 분석되었다. 또한 본 연구에서는 이를 시정하기 위한 소규모 공사의 실적공사비 보정방안을 제안하였다.

Efficient Lambda Logic Based Optimisation Procedure to Solve the Large Scale Generator Constrained Economic Dispatch Problem

  • Adhinarayanan, T.;Sydulu, M.
    • Journal of Electrical Engineering and Technology
    • /
    • 제4권3호
    • /
    • pp.301-309
    • /
    • 2009
  • A simple and efficient Lambda logic (${\lambda}-logic$) based algorithm is proposed for the solution of the generator constrained economic dispatch problem when the generating units having prohibited zones. The proposed method solves the economic dispatch (ED) problem that takes into account ramprate limits, transmission losses and prohibited operating zones in the power system operation. The proposed method uses a simple heuristic rule based on average power of prohibited operating zones which produces the feasibility of solution for the restricted operating units. The effectiveness of the algorithm is tested on five different test systems and the performance compared with other relevant methods reported in the literature. In all the cases, the proposed algorithm performs better than the previous existing algorithms with a less computational burden.

피더부하 균등화지수를 이용한 배전계통의 긴급정전복구 및 부하균등화 (Emergency Service Restoration and Load Balancing in Distribution Networks Using Feeder Loadings Balance Index)

  • 최상열;정호성;신명철
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제51권5호
    • /
    • pp.217-224
    • /
    • 2002
  • This paper presents an algorithm to obtain an approximate optimal solution for the service restoration and load balancing of large scale radial distribution system in a real-time operation environment. Since the problem is formulated as a combinatorial optimization problem, it is difficult to solve a large-scale combinatorial optimization problem accurately within the reasonable computation time. Therefore, in order to find an approximate optimal solution quickly, the authors proposed an algorithm which combines optimization technique called cyclic best-first search with heuristic based feeder loadings balance index for computational efficiency and robust performance. To demonstrate the validity of the proposed algorithm, numerical calculations are carried out the KEPCO's 108 bus distribution system.

Generation of the Orthoimage with the Correction of Building Occlusion

  • Yoo, Hwan-Hee;Sohn, Duk-Jae;Park, Hong-Gi
    • Korean Journal of Geomatics
    • /
    • 제1권1호
    • /
    • pp.7-13
    • /
    • 2001
  • Geospatial Information Systems (GIS) have been employed to systematically manage and design land use in urban areas. This has increased the need for more accurate vector and raster data. In Korea, l/l,000-scale digital maps are used as vector data for the facility management in urban areas. This has increased the need for large scale orthoimages. Orthoimages generated from aerial imagery can provide accurate information, making possible the more effective city management. However, there is a large problem in using the orthoimages, i.e., currently available conventional orthoimages have not been generated based on Digital Elevation Model (DEM) that takes into account the building heights. So this causes the displacements of building image in large scale orthoimages. The present study is an attempt to generate the large scale orthoimages based on building DEM. The semiautomatic building extraction method can detect building outlines by mouse clicking on either building roofs or corners. Building DEM, based on the outline and calculated building height, was used to produce the large scale orthoimages with the corrected building occlusion.

  • PDF

대규모 무선 센서 네트워크에서 종단 간 전송 성공률 향상을 위한 기회적 라우팅 기반 다중 경로 전송 방안 (Multipath Routing Based on Opportunistic Routing for Improving End-to-end Reliability in Large-scale Wireless Sensor Networks)

  • 김상대;김경훈;김기일
    • 대한임베디드공학회논문지
    • /
    • 제14권4호
    • /
    • pp.177-186
    • /
    • 2019
  • In wireless sensor networks, the transmission success ratio would be decreased when the scale of the WSNs increased. To defeat this problem, we propose a multipath routing based on opportunistic routing for improving end-to-end reliability in large-scale wireless sensor networks. The proposed scheme exploits the advantages of existing opportunistic routing and achieves high end-to-end success ratio by branching like a multipath routing through local decision without information of the whole network. As a result of the simulation result, the proposed scheme shows a similar or higher end-to-end transmission success ratio and less energy consumption rather than the existing scheme.

Large-scale 3D fast Fourier transform computation on a GPU

  • Jaehong Lee;Duksu Kim
    • ETRI Journal
    • /
    • 제45권6호
    • /
    • pp.1035-1045
    • /
    • 2023
  • We propose a novel graphics processing unit (GPU) algorithm that can handle a large-scale 3D fast Fourier transform (i.e., 3D-FFT) problem whose data size is larger than the GPU's memory. A 1D FFT-based 3D-FFT computational approach is used to solve the limited device memory issue. Moreover, to reduce the communication overhead between the CPU and GPU, we propose a 3D data-transposition method that converts the target 1D vector into a contiguous memory layout and improves data transfer efficiency. The transposed data are communicated between the host and device memories efficiently through the pinned buffer and multiple streams. We apply our method to various large-scale benchmarks and compare its performance with the state-of-the-art multicore CPU FFT library (i.e., fastest Fourier transform in the West [FFTW]) and a prior GPU-based 3D-FFT algorithm. Our method achieves a higher performance (up to 2.89 times) than FFTW; it yields more performance gaps as the data size increases. The performance of the prior GPU algorithm decreases considerably in massive-scale problems, whereas our method's performance is stable.

슬라이딩 모드를 이용한 대규모 계통의 제어 (The Control of Large Scale System by Sliding Mode)

  • 천희영;박귀태;곽군평;김동식;임형용
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
    • /
    • pp.190-194
    • /
    • 1987
  • This paper describes a new method for control of large-scale system by sliding mode. The concepts of control to large-scale system on the basis of VSS(Variable Structure System) control theory are used to decompose a large control problem into a two-level algorithm such that each subsystem is stabilized with local discontinuous controllers and higher level corrective control is designed to take into account the effect of interaction among the subsystems. In this paper, we show that each subsystem is controlled with repect to local continuous and higher level corrective control. This algorithm can be easily applied to multi-variable control system and obtained a continuous control in comparison With variable structure control systems. Two numerical examples are discussed as illustrations.

  • PDF

실대형화재평가장치의 개발 및 안정화에 관한 연구 (The Study of Development and Calibration for the Real Scale Fire Test Facility)

  • 유용호;김흥열;신현준
    • 한국화재소방학회논문지
    • /
    • 제22권1호
    • /
    • pp.37-44
    • /
    • 2008
  • 최근 화재와 관련된 연구가 활발해지면서 축소모형실험 등을 통한 연구가 진행되어 왔다. 그러나 실물화재 실험과의 직접적인 상관관계를 설명하기에는 충분하지 못하기 때문에 실물화재에 대한 관심이 증가되어 왔다. 따라서 본 연구에서는 산소소모율법을 적용한 10 MW급 라지스케일로리미터를 개발하였으며, 헵탄 풀 화재를 이용한 발열량 보정을 수행하였다. 그 결과 신뢰성 높은 보정결과를 얻었으며, 보다 진보적인 실물화재연구에 적용할 수 있음을 확인할 수 있었다.

Performance Analysis of Gas Turbine for Large-Scale IGCC Power Plant

  • Joo, Yong-Jin;Kim, Mi-Yeong;Park, Se-Ik;Seo, Dong-Kyun
    • KEPCO Journal on Electric Power and Energy
    • /
    • 제2권3호
    • /
    • pp.415-419
    • /
    • 2016
  • As the need for clean coal technology has grown, so has the global research and development efforts into integrated gasification combined cycle (IGCC) plants. An IGCC plant couples a gas turbine to a gasification block. Various technical and economic problems exist in designing such a system. One such problem is the difficulty in realizing economies of scale because the single-train flow capacity of commercial IGCC synthetic gas turbine plants is limited; the capacity does not exceed a net power rating of 300 MW. To address this problem, this study modeled and simulated a synthetic gas turbine with the goal of evaluating the feasibility of a 500 MW or larger IGCC plant. First, a gas turbine with the best output and efficiency was chosen for use with natural gas. The turbine was modeled using GateCycle (a simulation tool), and the integrity of the model validated by comparing the result to the design value. Next, off-design modeling was carried out for a gas turbine with synthetic gas based on its on-design model, and the result was compared with the study result of the gas turbine manufacturer. The simulation confirmed that it is possible to create a large capacity IGCC plant by undertaking the remodeling of a gas turbine designed to use natural gas into one suitable for synthetic gas.