• Title/Summary/Keyword: Holding capacity

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Effects of Thermal Properties and Water Retention Characteristics of Permeable Concrete Pavement on Surface Temperature (투.보수성 시멘트 콘크리트 포장의 열물성 및 수분보유특성이 표면온도에 미치는 영향)

  • Ryu Nam-Hyang;Yoo Byung-Rim
    • Journal of the Korean Institute of Landscape Architecture
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    • v.34 no.1 s.114
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    • pp.21-36
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    • 2006
  • This study was undertaken to analyze the effects of pavement thermal properties and water retention characteristics on the surface temperature of the gray permeable cement concrete pavement during the summer. Following is a summary of major results. 1) The hourly surface temperature of pavement could be well predicted with a heat transfer model program that incorporated the input data of major meteorological variables including solar radiation, atmospheric temperature, dew point, wind velocity, cloudiness and the evaporation rate of the pavements predicted by the time domain reflectometry (TDR) method. 2) When the albedo was changed to 0.5 from an arbitrary starting condition of 0.3, holding other variables constant, the peak surface temperature of the pavement dropped by 11.5%. When heat capacity was changed to $2.5\;kJm^{-3}K^{-1}\;from\;1.5\;kJm^{-3}K^{-1}$, surface temperature dropped by 8.0%. When daily evaporation was changed to 1 mm from 2 mm, temperature dropped by 5.7%. When heat conductivity was changed to $2.5\;Wm^{-1}K^{-1}\;from\;1.5\;Wm^{-1}K^{-1}$, the peak surface temperature of the pavement fell by 1.2%. The peak pavement surface temperature under the arbitrary basic condition was $24.46^{\circ}C$ (12 a.m.). 3) It accordingly became evident that the pavement surface temperature can be most effectively lowered by using materials with a high albedo, a high heat capacity or a high evaporation at the pavement surface. The glare situation, however, is intensified by raising of the albedo, moreover if reflected light is absorbed into surrounding physical masses, it is changed into heat. It accordingly became evident that raising the heat capacity and the evaporative capacity may be the moot acceptable measures to improve the thermal characteristics of the pavement. 4) The sensitivity of the surface temperature to major meteorological variables was as follows. When the daily average temperature changed to $0^{\circ}C\;from\;15^{\circ}C$, holding all other variables constant, the peak surface temperature of the pavement decreased by 56.1 %. When the global solar radiation changed to $200\;Wm^{-2}\;from\;600\;Wm^{-2}$, the temperature of the pavement decreased by 23.4%. When the wind velocity changed to $8\;ms^{-1}\;from\;4\;ms^{-1}$, the temperature decreased by 1.4%. When the cloudiness level changed to 1.0 from 0.5, the peak surface temperature decreased by 0.7%. The peak pavement surface temperature under the arbitrary basic conditions was $24.46^{\circ}C$ (12 a.m.)

Distribution Planning for Capacitated Supply Chains Using Tabu Search Approach (타부 탐색을 이용한 생산능력 제한하의 공급망 분배계획)

  • Kwon, Ick-Hyun;Baek, Jong-Kwan;Kim, Sung-Shick
    • IE interfaces
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    • v.18 no.1
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    • pp.63-72
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    • 2005
  • In this paper, we present a distribution planning method for a supply chain. Like a typical distribution network of manufacturing firms, we have the form of arborescence. To consider more realistic situation, we investigated that an outside supplier has limited capacity. The customer demands are given in deterministic form in finite number of discrete time periods. In this environment, we attempt to minimize the total costs, which is the sum of inventory holding and backorder costs over the distribution network during the planning horizon. To make the best of the restricted capacity, we propose the look-ahead feature. For looking ahead, we convert this problem into a single machine scheduling problem and utilize tabu search approach to solve it. Numerous simulation tests have shown that the proposed algorithm performs quite well.

A Study of Micro-piles Method combined with the Resisting Fixture interacting the power of frictional resistance in a contrary direction (양방향 저항체를 결합한 마이크로파일공법 연구)

  • Baik, Dong-Ho;Lee, Sang-Moo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.74-75
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    • 2014
  • In remodeling business or construction of both new strucures and existing structures, Case that pile foundation was set is often. Micro pile, holding compressive force and tensile force by spherical friction, is supported by skin friction rather than end bearing capacity. but, This is weak in tension. Active area of micro pile's skin friction is narrow and micro pile don't do unification behavior hence. So bearing capacity was not fully mobilized in existing researching. In this study, in order to compensate for this method, micro pile to install Resisting Fixture is proposed.

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Effects of Electron Beam Irradiation on Functional and Other Associated Properties of Pork Myofibrillar Salt-Soluble Proteins

  • Koh, Kwang-Hwan;Lee, Sam-Pin;Whang, Key
    • Preventive Nutrition and Food Science
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    • v.11 no.1
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    • pp.73-77
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    • 2006
  • Ground pork was irradiated with an electron beam (e-beam) at a dose of 0, 1.5, 3, 5 and 10 kGy and the changes in various functional and other associated properties of salt-soluble proteins extracted from the pork were evaluated. Irradiation did not affect turbidity and the disulfide content of pork salt-soluble protein, but the content of sulfhydryls and the hydrophobocity of salt-soluble protein increased. This indicates that protein degradation occurred when the pork was e-beam irradiated and that the sulfhydryls and hydrophobic moieties buried inside the proteins were exposed to the outside environment. However, these degraded protein molecules did not form large protein aggregates through disulfide bridges. The emulsifying capacity of the pork increased with irradiation, which could be the result from increased hydrophobicity of pork salt-soluble protein. Water holding capacity of pork was not affected bye-beam irradiation.

Look-ahead Based Distribution Planning for Capacitated Multi-stage Supply Chains (생산 능력 제한이 존재하는 다단계 공급망을 위한 Look-ahead 기반의 분배계획)

  • Roh, Joo-Suk;Kwon, Ick-Hyun;Kim, Sung-Shick
    • Journal of the Korea Safety Management & Science
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    • v.8 no.5
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    • pp.139-150
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    • 2006
  • The aim of this study is to establish an efficient distribution planning for a capacitated multi-stage supply chain. We assume that the demand information during planning horizon is given a deterministic form using a certain forecasting method. Under such a condition, we present a cost effective heuristic method for minimizing chain-wide supply chain inventory cost that is the sum of holding and backorder costs by using look-ahead technique. We cope with the capacity restriction constraints through look-ahead technique that considers not only the current demand information but also future demand information. To evaluate performance of the proposed heuristic method, we compared it with the extant research that utilizes echelon stock concept, under various supply chain settings.

Generalized Proxy-Assisted Periodic Broadcasting (G-ProB) for Heterogeneous Clients in Video-on-Demand Service

  • Febiansyah, Hidayat;Kwon, Jin-Baek
    • Journal of Information Processing Systems
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    • v.6 no.4
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    • pp.575-596
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    • 2010
  • Video-on-Demand services are increasing rapidly nowadays. The load on servers can be very high, even exceeding their capacity. For popular contents, we can use a Periodic Broadcast (PB) strategy using multicast to serve all clients. Recent development of PB uses multiple channels broadcasting for segments of movies in certain patterns, so that users only need to wait for a small segment to start the service. However, users need higher download capacity to download multiple segments at a time. In order to compensate for this, a proxy server can help to reduce download bandwidth requirements by holding some segments for a certain time. This research will focus on more recent PB schemes that couldn't be covered by previous Proxy-Assisted Periodic Broadcast strategies.

Evaluation of Storage Policies with Production Lot-Sizing Consideration in an AS/RS

  • Lee, Moon-Kyu
    • Journal of Korean Institute of Industrial Engineers
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    • v.18 no.1
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    • pp.11-24
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    • 1992
  • The performance of Storage assignment policies is traditionally evaluated with the storage capacity of and AS/RS taken as given. However, the storage capacity is closely related to the inventory model used in real situations. This paper presents a model of evaluating the performance of three storage policies(random storage, class-based storage, and full turnover-based storage) considering production lot-sizing simultaneously with storage assignment of inventory items. The objective of the model is to achieve a balance of warehouse throughput and space requirements such that a total of material handling cost, production ordering cost, and inventory holding cost is minimized. The effects of the parameters involved in the model are investigated on the performance of each storage policy through example problems.

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A Study on Filtration System Model and Comparative Performance Tests of Automotive (여과시스템 모델과 자동차 연료필터의 비교성능시험 연구)

  • 이재천
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.3
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    • pp.194-201
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    • 2003
  • This study presents the comparative filtration performance evaluation of automotive fuel filters based on the theory of Beta ratio. For the experiments, the fuel component's test stand incorporating the multi-pass filtration test circuit was developed. A mathematical description of filtration process in general was derived. And the theoretical basis of multi-pass test and the test procedure were described in detail. Experimental results revealed that domestic fuel filter tested could not maintain consistent Beta ratio, that is filtration efficiency, although it had the holding capacity of contaminants close to the specification at maximum pressure drop across the filter assembly. The results of experiments and simulations also showed that filtration system model could be refined including desorption ratio to estimate the variable Beta ratio in service life.

Physicochemical Characteristic of Ultrafine Sparassis crispa(cauliflower mushroom) Powder

  • Sun-Sun Hur
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.5
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    • pp.945-954
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    • 2023
  • In this study, Sparassis crispa(cauliflower mushroom), which is rich in beta-glucan, was pulverized using ultrafine grinding technology for its potential utilization as a diverse food ingredient. The physical and antioxidant properties of cauliflower mushroom powder were evaluated at various grinding times. The results showed that as the grinding time of cauliflower mushroom increased, the average particle size significantly decreased (p<0.05). Additionally, the water-holding capacity, swelling capacity, and water solubility index of cauliflower mushroom increased significantly(p<0.05). Based on the analysis mentioned above, cauliflower mushroom prepared as a superfine powder for 5 minutes exhibited superior physical and chemical properties as well as antioxidant characteristics and is expected to be widely used in various foods.