• Title/Summary/Keyword: storage ratio

Search Result 1,448, Processing Time 0.029 seconds

Numerical Analysis of Fluid and Thermal Characteristics on Live Fishing Tank of Small Fishing Boat (소형어선용 어창내의 열 유동특성 해석)

  • 한인근;문춘근;김재돌;윤정인
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.25 no.6
    • /
    • pp.1324-1329
    • /
    • 2001
  • The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

  • PDF

Feasibility Study on Installing a Multi-functional Storage Facility (하수저류시설 타당성 분석 연구)

  • Ryu, Jae-Na;Oh, Jei-ll;Lee, Kyoung-Yong
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.25 no.6
    • /
    • pp.935-947
    • /
    • 2011
  • In the era of climate change, the feasibility of a 'multi-functional storage facility' was evaluated in terms of various key performance indices such as flooding prevention effects, urban pollution reduction effects, and rainwater harvesting effects. As a result, the Korea Ministry of Environment introduced a new concept of 'multi-functional storage facility' for sewer flooding prevention and urban non-point pollution reduction. Prior to introducing these infrastructure (a large underground storage facility), the more details were needed to be examined carefully in all of technical aspects of construction and management. It was also well known that the validity of installation of 'multi-functional storage facility' was sometimes weakened because of a low B/C ratio.

Analysis and Optimization of a 2-Class-based Dedicated Storage System (2지역/지정위치 저장시스템의 분석과 최적화)

  • Yang, Moonhee
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.29 no.3
    • /
    • pp.222-229
    • /
    • 2003
  • In this paper, we address a layout design problem, PTN[2], for determining an appropriate 2-class-based dedicated storage layout in a class of unit load storage systems. Our strong conjecture is that PTNI2] is NP-hard. Restricting PTN[2], we provide three solvable cases of PTN[2] in which an optimal solution to the solvable cases is one of the partitions based on the PAI(product activity index)-nonincreasing ordering. However, we show with a counterexample that a solution based on the PAI-non increasing ordering does not always give an optimal solution to PTN[2]. Utilizing the derived properties, we construct an effective heuristic algorithm for solving PTN[2] based on a PAI-non increasing ordering with performance ratio bound. Our algorithm with O($n^2$) is effective in the sense that it guarantees a better class-based storage layout than a randomized storage layout in terms of the expected single command travel time.

Relationship between Contrast Ratio of Conductive Particle and Contact Resistance on COG Bonding using ACF (ACF를 이용한 COG 접합 공정에서 도전볼의 음영비와 접촉 저항과의 관계)

  • Jin, Songwan;Jeong, Young Hun;Choi, Eun Soo;Kim, Bosun;Yun, Won-Soo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.31 no.9
    • /
    • pp.831-838
    • /
    • 2014
  • Chip on glass (COG) bonding using anisotropic conductive film (ACF) is a key technology to assemble a driver IC onto a LCD glass panel. In this paper, an experimental investigation was conducted to investigate the correlation between contact resistance and characteristics of image taken by machine vision based inspection system. The results show that the contact resistance was strongly influenced by the contrast ratio of conductive particle rather than the number of conductive particles. Also, number of conductive particles whose contrast ratio is below 0.75 is crucial for determining the quality of the assembled samples. On the other hand, in the result of high temperature high humidity storage test, the contrast ratio of samples was increased. However, in the case of open-circuit samples after temperature humidity storage test, the number of conductive particles whose contrast ratio is above 0.75 was more than that of the closed-circuit samples.

A Study on the Typology of Agricultural Reservoir for Effective Safety Inspection Systems (효율적인 안전진단 체계 수립을 위한 농업용 저수지 유형화 연구)

  • Lee, Chang Beom;Jung, Nam Su;Park, Seong Ki;Jeon, Sang Ok
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.57 no.5
    • /
    • pp.89-99
    • /
    • 2015
  • In this research, 1,032 data of precise safety inspection from 2004 to 2013 are gathered and constructed for finding effective safety inspection systems. Items are extracted from constructed data and factors for typology are decided with statistical method such as principle component analysis and cluster analysis. For factor decision, we extruded independent characteristics such as morphological and geographical characteristic, and deleted items which can be expressed by combination of independent characteristics. Four factors such as total storage, watershed ratio, levee length ratio, and spillway length ratio are extracted in this process. In cluster analysis, levee length ratio is excluded because it is not separated as cluster. Finally nine types of agricultural reservoir are extruded by total storage, watershed ratio, and spillway length ratio with frequency analysis.

Regeneration of Ectomycorrhizal Fungal Isolates Following Deep Freezer Storage

  • Obase, Keisuke;Lee, Sang-Yong;Chun, Kun-Woo;Lee, Jong-Kyu
    • Mycobiology
    • /
    • v.39 no.2
    • /
    • pp.133-136
    • /
    • 2011
  • Mycelial growth and survival ratio of ectomycorrhizal fungi were determined after storage at $-70^{\circ}C$ for 1, 3, or 6 mon. Seventeen of 23 ectomycorrhizal fungi did not survive after storage for more than 6 mon, whereas Cenococcum geophilum, Lepista nuda, and some species of Rhizopogon and Suillus did survive.

CA Storage for Ginger Depending on CO2 Concentrations (탄산가스 농도에 따른 생강의 CA 저장효과)

  • 정문철;이세은
    • Food Science and Preservation
    • /
    • v.5 no.2
    • /
    • pp.133-137
    • /
    • 1998
  • In order to establish effectiveness of CA storage and adequate CO2 concentration, it was investigated the quality chanties of Singer during CA storage for 150 days at different CO2 concentrations ranging from 3% to 12% and 3% fixed oxygen concentration. Weight loss tend to decrease with increase of CO2 concentrations. Sprouting ratio and the loss of gingerol was shown to be less as CO2 concentration increase but to be more than control stored at 12$^{\circ}C$, 95% RH within the concentration less than 6% CO2.

  • PDF

An experimental study on the factors to improve the formation performance of gas hydrate (가스하이드레이트 제조성능 향상을 위한 영향인자 검토 연구)

  • Shin, Chang-Hoon;Kim, Yu-Na;Kwon, Ok-Bae;Park, Seung-Su;Han, Jeong-Min;Lee, Jeong-Hwan
    • Proceedings of the KSME Conference
    • /
    • 2007.05b
    • /
    • pp.2989-2994
    • /
    • 2007
  • Gas hydrates are ice-like crystalline compounds that form under low temperature and elevated pressure conditions. Although hydrate formation can pose serious flow-assurance problems in the gas pipelines or facilities, gas hydrates present a novel means for natural gas storage and transportation with potential applications in a wide variety of areas. An important property of hydrates that makes them attractive for use in gas storage and transportation is their very high gas-to-solid ratio. In addition to the high gas content, gas hydrates are remarkably stable. The main barrier to development of gas hydrate technology is the lack of an effective method to mass produce gas hydrate in solid form. The first objective of this study is investigating the characteristics of gas hydrate formation related to several factors such as pressure, temperature, water-to-storage volume ratio, concentration of SDS, heat transfer and whether stirred or not respectively. And the second objective is clarifying the relation between the formation efficiency and each factor in order to find the proper way or direction to improve the formation performance.

  • PDF

A Study on the Battery Storage Volume Optimization in case of DR Participation for the Minimization of the Customer's Investment Cost (BESS의 DR(Demand Response) 적용 시 수용가의 투자비 최소화를 위한 적정용량산출방법)

  • Yang, Seung-Kwon;Kim, Dae-Young
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.27 no.1
    • /
    • pp.17-23
    • /
    • 2013
  • The BESS(Battery Energy Storage System) is an useful device for load leveling, but the high cost, installation space and safety issues are the main barriers for supplying it widely. The important factor in supplying BESS to customers successfully is the payback period. As most of the H/W cost factors are uncontrollable, the optimization of storage volume can be useful factor in improving payback period. In order to obtain optimized BESS volume, the load factor, demand ratio, peak shaving ratio, electric rates and benefits from DR participation of customer should be analyzed. In this paper, we could verify the peak cutting capability and cost effectiveness under the some proposed conditions and changing value of PCS and battery based on the customers data after volume optimization process was applied, and we can identified the saturation point of load factor and shortening of customer's payback period.

Estimation of irrigation supply from agricultural reservoirs based on reservoir storage data

  • Kang, Hansol;An, Hyunuk;Lee, Kwangya
    • Korean Journal of Agricultural Science
    • /
    • v.46 no.4
    • /
    • pp.999-1006
    • /
    • 2019
  • Recently, the quantitative management of agricultural water supply, which is the main source for water consumption in Korea, has become more important due to the effective water management organization of the Korean government. In this study, the estimation method for irrigation supply based on agricultural reservoir storage data was improved compared to previous research, in which drought year selection was unclear, and the outlier data for the rainfall-irrigation supply were not eliminated in the regression analysis. In this study, the drought year was selected by the ratio of annual precipitation to mean annual precipitation and the storage rate observed before the start of irrigation. The outlier data for the rainfall-irrigation supply were eliminated by the Grubbs & Beck test. The proposed method was applied to nine agricultural reservoirs for validation. As a result, the ratio of annual precipitation to mean annual precipitation is less than 53% and the storage rate observed before the start of irrigation is less than 55% it was judged to be the drought year. In addition, the drought supply factor, K, was found to be 0.70 on average, showing closer results to the observed reservoir rates. This shows that water management at the real is appling drought year practice. It was shown that the performance of the proposed method was satisfactory with NSE (Nash-Sutcliffe model efficiency coefficient) and R2 (coefficient of determiniation) except for a few cases.