• Title/Summary/Keyword: load limits

Search Result 315, Processing Time 0.029 seconds

Water Quality Impact Assessment in Korea - Comparing with the Integrated Control of Pollutant-Discharging Facilities - (수질분야 환경영향평가의 개선방안 - 환경오염시설의 통합관리와 대비하여 -)

  • Lee, Jong Ho;Cho, Jae Heon
    • Journal of Environmental Impact Assessment
    • /
    • v.26 no.5
    • /
    • pp.331-343
    • /
    • 2017
  • The important changes in water environment management in Korea can be summarized as the enactment of Act on the Integrated Control of Pollutant-Discharging Facilities. Therefore water quality impact assessment should be reexamined and be revised. This study examines the present water quality impact assessment items (permissible discharge limits, standards for effluent water quality including Total Pollutant Load Management System) and considers the land use regulation for water quality conservation and NVZs(Nitrate Vulnerable Zones of EU and England). It also considers lately adopted standards(maximum discharge standards, permissible discharge standards, and marginal discharge standards etc) based on Act on the Integrated Control of Pollutant-Discharging Facilities and then compares Korean BAT and its counterpart control technology of U.S.A. And it also compares the items of water quality impact assessment with those of Integrated Control of Pollutant-Discharging Facilities, based on EIS reporting items. This study suggests five improvement measures for water quality impact assessment. First reflection of discharge impact analysis on impact prediction and assessment, second reflection of permissible discharge standards on agreed standards in the EIA procedure, third, reflection of diversified BAT on mitigation measures in the EIA procedure, forth introduction of land use regulation such as NVZs, finally strengthening linkage between water quality items and land use items etc.

Cloud P2P OLAP: Query Processing Method and Index structure for Peer-to-Peer OLAP on Cloud Computing (Cloud P2P OLAP: 클라우드 컴퓨팅 환경에서의 Peer-to-Peer OLAP 질의처리기법 및 인덱스 구조)

  • Joo, Kil-Hong;Kim, Hun-Dong;Lee, Won-Suk
    • Journal of Internet Computing and Services
    • /
    • v.12 no.4
    • /
    • pp.157-172
    • /
    • 2011
  • The latest active studies on distributed OLAP to adopt a distributed environment are mainly focused on DHT P2P OLAP and Grid OLAP. However, these approaches have its weak points, the P2P OLAP has limitations to multidimensional range queries in the cloud computing environment due to the nature of structured P2P. On the other hand, the Grid OLAP has no regard for adjacency and time series. It focused on its own sub set lookup algorithm. To overcome the above limits, this paper proposes an efficient central managed P2P approach for a cloud computing environment. When a multi-level hybrid P2P method is combined with an index load distribution scheme, the performance of a multi-dimensional range query is enhanced. The proposed scheme makes the OLAP query results of a user to be able to reused by other users' volatile cube search. For this purpose, this paper examines the combination of an aggregation cube hierarchy tree, a quad-tree, and an interval-tree as an efficient index structure. As a result, the proposed cloud P2P OLAP scheme can manage the adjacency and time series factor of an OLAP query. The performance of the proposed scheme is analyzed by a series of experiments to identify its various characteristics.

A Study on the Libraries' Competitiveness Reinforcement Measures through SWOT Analysis : Based on the Case Study of University A's Library (SWOT 분석을 통한 도서관의 경쟁력 제고 방안에 관한 연구 - A대학교 도서관의 사례를 중심으로 -)

  • Noh, Dong-Jo
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.40 no.1
    • /
    • pp.335-351
    • /
    • 2006
  • For a library to be run more efficiently, its internal strengths and weaknesses, external opportunities and threats must be determined for forecasting on the basis of the diagnosis of the internal and external environment and situations, and optimum strategies and measures responsively deducted and utilized. Therefore, I had analyzed the strategic competition of university A's library using SWOT analysis, which has recently been spotlighted as an effective strategic competition analysis method. The conclusions thus obtained are as explained below. Firstly. the strengths of university A's library are the professional qualifications of the employees. work efficiency based on systematic operative plans and division of work load, and provision of high quality service following the establishment of the digital library. Secondly, its weaknesses are the insufficiency and limits of the usable resources, the lack of progressive future operation plans and systems, and the deficiency of a positive service mind. Thirdly, the opportunities are the possibility for new developments in accordance with the digital information environment. reinforcement of the operative efficiency throughout expanding its cooperation with external organizations and other libraries, and its transformation as the local library hub by opening up to the public. Fourthly, the threats are the lack of the school authorities' acknowledgement. and the degradation of the library's status in accordance, the users' various requests for information and advanced professional service according to the rapidly changing information environment. and the restriction of the library service based on the copyright law. Fifthly, as a result of analyzing the strategic competition of university A's library, measures such as the reinforcement of digital service by acquiring digital specialists. provision of extended service through active cooperation with external institutes and libraries. development and provision of differentiated service in accordance with the reinforced copyright law were proposed to improve the library's future competitiveness.

Transverse Reinforcement for Circular Internally Confined Hollow RC column (원형 내부 구속 중공 RC 기둥의 심부 구속 횡방향 철근 연구)

  • Won, Deok Hee;Han, Taek Hee;Park, Woo Sun;Park, Jong Sub;Kang, Young Jong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.2
    • /
    • pp.927-935
    • /
    • 2013
  • Recently, bridge structures has progressed the researches about seismic performance by occurrence of earthquake increased compared with the past. In the substructure of bridge, confining transverse reinforcement has arranged in plastic hinge region to resist the lateral load which increased the lateral confining effect. Columns are increased the seismic performance through secure of the stiffness and ductility The design specification for arrangement of confining transverse reinforcement same specification of domestic and international that suggested to solid reinforced concrete column(RC). This design specification have limits for Internally Confined Hollow RC(ICH RC) column because of different the component and performance characteristics of column. In this paper suggested the modified equation for economics and rational design through investigation of displacement ductility when applied the existing specification at the steel composite hollow RC column.

Assessment of a Pre-conceptual Design of a Spent PWR Fuel Disposal Container (가압경수로형 사용후핵연료 처분용기의 예비 개념설계 평가)

  • Choi, Jong-Won;Cho, Dong-Keun;Lee, Yang;Choi, Heui-Joo;Lee, Jong-Youl
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.4 no.1
    • /
    • pp.41-50
    • /
    • 2006
  • In this paper, sets of engineering analyses were conducted to renew the overall dimensions and configurations of a disposal container proposed as a prototype in the previous study. Such efforts and calculation results can provide new design variables such as the inner basket array type and thickness of the outer shell and the lid & bottom of a spent nuclear fuel disposal container. These efforts include radiation shielding and nuclear criticality analyses to check to see whether the dimensions of the container proposed from the mechanical structural analyses can provide a nuclear safety or not. According to the results of the structural analysis of a PWR disposal container by varying the diameter of the container insert, the Maximum Von Mises stress from the 102 cm-container meets the safety factor of 2.0 for both extreme and normal load conditions. This container also satisfies the nuclear criticality and radiation safety limits. This decrease in the diameter results in a weight loss of a container by $\sim20$ tons.

  • PDF

Pre-conceptual Design of a Spent PWR Fuel Disposal Container (가압경수로형 사용후핵연료 처분용기의 예비 개념설계 평가)

  • CHO Dong-Keun;CHOI Jongwon;Lee Yang;CHOI Heui-Joo;LEE Jong-Youl
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2005.11a
    • /
    • pp.153-162
    • /
    • 2005
  • In this Paper, sets of engineering analyses were conducted to renew the overall dimensions and configurations of a disposal container proposed as a prototype in the previous study. Such efforts and calculation results can provide new design variables such as the inner basket array type and thickness of the outer shell and the lid & bottom of a spent nuclear fuel disposal container. These efforts include radiation shielding and nuclear criticality analyses to check to see whether the dimensions of the container proposed from the mechanical structural analyses can provide a nuclear safety or not. According to the results of the structural analysis of a PWR disposal container by varying the diameter of the container insert, the Maximum Von Mises stress from the 102 cm container meets the safety factor of 2.0 for both extreme and normal load conditions. This container also satisfies the nuclear criticality and radiation safety limits. This decrease in the diameter results in a weight loss of a container by ${\~}$20 tons.

  • PDF

Fair Queuing for Mobile Sink (FQMS) : Scheduling Scheme for Fair Data Collection in Wireless Sensor Networks with Mobile Sink (모바일 싱크를 위한 균등 큐잉(FQMS) : 모바일 싱크 기반 무선 센서 네트워크에서 균등한 데이터 수집을 위한 스케줄링 기법)

  • Jo, Young-Tae;Park, Chong-Myung;Lee, Joa-Hyoung;Seo, Dong-Mahn;Lim, Dong-Sun;Jung, In-Bum
    • Journal of KIISE:Information Networking
    • /
    • v.37 no.3
    • /
    • pp.204-216
    • /
    • 2010
  • Since Sensor nodes around a fixed sink have huge concentrated network traffic, the battery consumption of them is increased extremely. Therefore the lifetime of sensor networks is limited because of huge battery consumption. To address this problem, a mobile sink has been studied for load distribution among sensor nodes. Since a mobile sink changes its location in sensor networks continuously, the mobile sink has time limits to communicate with each sensor node and unstable signal strength from each sensor node. Therefore, a fair and stable data collection method between a mobile sink and sensor nodes is necessary in this environment. When some sensor nodes are not able to send data to the mobile sink, a real-time application in sensor networks cannot be provided. In this paper, the new scheduling method, FQMS (Fair Queuing for Mobile Sink), is proposed for fair and stable data collection for mobile sinks in sensor networks. The FQMS guarantees balanced data collecting between sensor nodes for a mobile sink. In out experiments, the FQMS receives more packets from sensor nodes than legacy scheduling methods and provides fair data collection, because moving speed of a mobile sink, distance between a mobile sink and sensor nodes and the number of sensor nodes are considered.

Shape Optimum Design of Pultruded FRP Bridge Decks (인발성형된 FRP 바닥판의 형상 최적설계)

  • 조효남;최영민;김희성;김형열;이종순
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.17 no.3
    • /
    • pp.319-332
    • /
    • 2004
  • Due to their high strength to weight ratios and excellent durability, fiber reinforced polymer(FRP) is widely used in construction industries. In this paper, a shape optimum design of FRP bridge decks haying pultruded cellular cross-section is presented. In the problem formulation, an objective function is selected to minimize the volumes. The cross-sectional dimensions and material properties of the deck of FRP bridges are used as the design variables. On the other hand, deflection limits in the design code, material failure criteria, buckling load, minimum height, and stress are selected as the design constraints to enhance the structural performance of FRP decks. In order to efficiently treat the optimization process, the cross-sectional shape of bridge decks is assumed to be a tube shape. The optimization process utilizes an improved Genetic Algorithms incorporating indexing technique. For the structural analysis using a three-dimensional finite element, a commercial package(ABAQUS) is used. Using a computer program coded for this study, an example problem is solved and the results are presented with sensitivity analysis. The bridge consists of a deck width of 12.14m and is supported by five 40m long steel girders spaced at 2.5m. The bridge is designed to carry a standard DB-24 truck loading according to the Standard Specifications for Highway Bridges in Korea. Based on the optimum design, viable cross-sectional dimensions for FRP decks, suitable for pultrusion process are proposed.

Behavior of FRP-Concrete Composite Decks with the Mechanical Connection (기계적 합성이 적용된 FRP-콘크리트 합성 바닥판의 거동 분석)

  • Kim, Sung-Tae;Park, Sung-Yong;Cho, Jeong-Rae;Kim, Byung-Suk;Cho, Keun-Hee
    • Journal of the Korea Concrete Institute
    • /
    • v.22 no.5
    • /
    • pp.609-616
    • /
    • 2010
  • FRP-concrete composite deck, an innovative system, is composed of concrete in the top and FRP panel in the bottom. Bottom FRP panel can reduce self weight and improve workability. This system requires strong connection between FRP and concrete. Therefore coarse sand coating was previously applied on FRP to improve the bonding. In this study, concrete wedge method is newly introduced to enhance both vertical bond and fatigue performance. Three FRP-concrete composite deck specimens with the concrete wedges were manufactured, and static and fatigue tests were carried out. The results showed that the new FRP-concrete composite deck satisfied deflection and crack width limits set by the design codes. And the fatigue test showed that the composite deck was capable of two million load cycles under 50% of its static strength. Based on the results, it can be concluded that that this new system has outstanding mechanical and durability performance, and therefore, satisfactorily be used in designing FRP-concrete composite deck.

Determination of Rare Earth Elements by Inductively Coupled Plasma Mass Spectrometry with Introduction of Organic Phase Using Ultrasonic Nebulizer (초음파 분무기를 이용한 유기상의 주입에 의한 희토류 원소의 유도결합 플라스마 질량분석법적 정량)

  • Lee, Sang Hak;Son, Bum Mok
    • Analytical Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.127-134
    • /
    • 2002
  • Analytical method to determine rare earth elements which were extracted to organic phase by inductively coupled plasma mass spectrometry(ICP-MS) was investigated. Organic phase which had extracted rare earth elements was directly aspirated into ICP-MS by ultrasonic nebulizer(USN) in order to reduce solvent load to the plasma. Then, the count rate increased when MIBK(methyl isobutyl ketone) was added to EtOH(ethanol) but decreased when 0.03 M HEH(2-ethylhexyl-2-ethylhexyl phosphonic acid, $P_{507}$, PC88A) was added to solvent which mixed MIBK with EtOH. The optimal temperatures of desolvation system were -10 $^{\circ}C$ for the condenser and 150 $^{\circ}C$ for the heating tube. The optimal nebulizer flow rate which gave maximum count rate and minimum reflect power was 0.7 L/min. The optimal pH and extraction time were 4.3 and 10 min for MIBK-0.03 M HEH system. Detection limits which were obtained through calibration curves at the range of 0.2 ${\sim}$ 20 ng/mL were 0.02 ${\sim}$ 0.05 ng/mL under the optimal experimental conditions.