• Title/Summary/Keyword: storages

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A study on the classification of storages in urban area (도시지역 저류시설 분류체계 연구)

  • Ryu, Jaena;Oh, Jeill;Lee, Ho Ryeong
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.5
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    • pp.637-647
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    • 2012
  • Recent series of flooding events in urban area has brought a growing concern on storage facilities as a major stormwater management method. The Korean Ministry of Environment has announced diverse plans to tackle the problem, including plans for multi-purpose storages which deal both the stormwater and wastewater. Even though storages can be categorized for different perspectives, classification of possible storages in urban area has not been throughly studied so far. This study investigated diverse references of urban storages and suggested systematic classifications on structural, functional and some other basis. Structural classification mainly concerns structural shape of facilities and includes (1)Cisterns & Rain barrels, (2)Forebays, (3)Dry basins, (4)Wet basins and (5)Constructed wetland. Those functions can be (1)flood prevention (2)water quality control and (3)reuse of stored water. Other criteria that categorize storages depend on (1)height, (2)location, (3)configuration, (4)depth, (5)site of the installation and (6)shape.

A Hydrologic Analysis for the Infiltration Storages Planned on Jeju-do (제주도에 계획된 침투저류지의 수문학적 분석 사례)

  • Lee, Sangho;Lee, Jungmin;Kang, Taeuk;Kang, Shinuk
    • Journal of Korean Society on Water Environment
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    • v.26 no.6
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    • pp.1040-1048
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    • 2010
  • An infiltration storage can be installed as a method of reducing runoff from catchment and increasing stream flow during the dry period by recharging groundwater. However, there is no proper model and method that can be used to design storage capacity of an infiltration storage in Korea. The purpose of the study is to evaluate capacities of infiltration storages planned on Jeju-do in Korea by modifying Storm Water Management Model (SWMM). The basic equations for the infiltration storage are same as those of the infiltration trench used in MIDUSS. Infiltration rates of the infiltration storages were first measured by double ring infiltrometers, and then the modified model was applied to evaluate adequacy for the capacities of three infiltration storages planned on Jeju-do in Korea. The application results show that the two infiltration storages with higher infiltration rates have adequate capacities to infiltrate the total water inflow to the storages. However, the other infiltration storage with lower infiltration rates has not sufficient capacity to infiltrate the total water inflow to the storage and release occurs to the downstream region. The simulation model and method applied can be used for capacity evaluation of future infiltration storages on highly pervious areas in Jeju-do.

A Study on Efficient RAID Storages using Flash Memory (플래시 메모리를 사용하는 효과적인 RAID 스토리지에 대한 연구)

  • Byun, Si-Woo;Hur, Moon-Haeng
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.240-242
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    • 2009
  • Flash memories are one of best media to support future computer's storages. However, we need to improve traditional data management scheme due to the relatively slow characteristics of flash operation of SSD. Due to the unique characteristics of flash media and hard disk, the efficiency of I/O processing is severely reduced without special treatment, especially in the presence of heavy workload or bulk data copy. In this respect, we need to design and develop efficient hybrid-RAID storage system.

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Optimal scheduling for multi-product batch processes under consideration of non-zero transfer times and set-up times

  • Jung, Jae-Hak;Lee, In-Beum;Yang, Dae-Ryook;Chang, Kun-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10b
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    • pp.30-35
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    • 1993
  • Simple recurrence relations for calculating completion times of various storage polices (unlimited, intermediate storages(FIS), finite intermediate storages(FIS), no intermediate storage(NIS), zero wait(ZW) for serial multi-product multi-unit processes are suggested. Not only processing times but also transfer times, set-up (clean-up) times of units and set-up times of storages are considered. Optimal scheduling strategies with zero transfer times and zero set-up times had been developed as a mixed integer linear programniing(MILP) formulation for several intermediate storage policies. In this paper those with non-zero transfer times, non-zero set-up times of units and set-up times of storages are newly proposed as a mixed integer nonlinear programming(MINLP) formulation for various storage polices (UIS, NIS, FIS, and ZW). Several examples are tested to evaluate the robustness of this strategy and reasonable computation times.

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Optimal Design of Batch-Storage Network (회분식 공정-저장조 그물망 구조의 최적설계)

  • 이경범;이의수
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.6
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    • pp.802-810
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    • 1998
  • The purpose of this study is to find the analytic solution of determining the optimal capacity of processes and storages to meet the product demand. Recent trend to reduce product delivery time and to provide high quality product to customer requires the increasing capacity of storage facilities. However, the cost of constructing and operating storage facilities is becoming substantial because of increasing land value, environmental and safety concern. Therefore, reasonable decision making about the capacity of processes and storages is important subject for industries. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ(Economic Order Quantity) model, trimmed with practical experience but the unrealistic assumption of EOQ model is not suitable for the chemical plant design with highly interlinked processes and storages. This study, a first systematic attempt for this subject, clearly overcomes the limitation of classical lot sizing method. The superstructure of the plant consists of the network of serially and/or parallelly interlinked processes and storages. A novel production and inventory analysis method, PSW(Periodic Square Wave) model, is applied. The objective function of optimization is minimizing the total cost composed of setup and inventory holding cost. The advantage of PSW model comes from the fact that the model provide a set of simple analytic solution in spite of realistic description of material flow between process and storage. The resulting simple analytic solution can greatly enhance the proper and quick investment decision for the preliminary plant design confronting diverse economic situation.

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Performance Evaluation of Flash Memory-Based File Storages: NAND vs. NOR (플래시 메모리 기반의 파일 저장 장치에 대한 성능분석)

  • Sung, Min-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.3
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    • pp.710-716
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    • 2008
  • This paper covers the performance evaluation of two flash memory-based file storages, NAND and NOR, which are the major flash types. To evaluate their performances, we set up separate file storages for the two types of flash memories on a PocketPC-based experimental platform. Using the platform, we measured and compared the I/O throughputs in terms of buffer size, amount of used space, and kernel-level write caching. According to the results from our experiments, the overall performance of the NAND-based storage is higher than that of NOR by up to 4.8 and 5.7 times in write and read throughputs, respectively. The experimental results show the relative strengths and weaknesses of the two schemes and provide insights which we believe assist in the design of flash memory-based file storages.

A Study on Calculating Relevant Length of Left Turn Storages Using UAV Spatial Images Considering Arrival Distribution Characteristics at Signalized Intersections in Urban Commercial Areas

  • Yang, Jaeho;Kim, Eungcheol;Na, Young-Woo;Choi, Byoung-Gil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.3
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    • pp.153-164
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    • 2018
  • Calculating the relevant length of left turn storages in urban intersections is very crucial in road designs. A left turn lane consists of deceleration lanes and left turn storages. In this study, we developed methods for calculating relevant lengths of left turn storages that vary at each intersection using UAV (Unmanned Aerial Vehicle) spatial images. Problems of conventional design techniques are applying the same number of left turn vehicles (N) using Poisson distribution without considering land use types, using a vehicle length that may not be measurable when applying the length of waiting vehicles (S), and using same storage length coefficient (${\alpha}$), 1.5, for every intersections. In order to solve these problems, we estimated the number of left turn vehicles (N) using an empirical distribution, suggested to use headways of vehicles for (S) to calculate the length of waiting vehicles (S) with a help of using UAV spatial images, and defined ranges of storage length coefficient (${\alpha}$) from 1.0 to 1.5 for flexible design. For more convenient design, it is suitable to classify two cases when possible to know and impossible to know about ratio of large trucks among vehicles when planning an intersection. We developed formula for each case to calculate left turn storage lengths of a minimum and a maximum. By applying developed methods and values, more efficient signalized intersection operation can be accomplished.

Sigma Hub for Efficiently Integrating USB Storages (USB 저장장치의 효율적인 통합을 위한 시그마 허브)

  • Choi, O-Hoon;Lim, Jung-Eun;Na, Hong-Seok;Baik, Doo-Kwon
    • Journal of KIISE:Databases
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    • v.35 no.6
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    • pp.533-543
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    • 2008
  • With technological advances for storage volume size of a semiconductor memory, USB storage is made as products to support a high capacity storage. Hereby, consumers discard pint-sized USB storages which they already had, or do not use them efficiently. To integrate and unify these pint-sized USB storages as one big USB storage, we proposed Sigma Hub. It can be grouping multiple USB storages, which have each different volume size of memory storage, as logical unity Storage through USB Hub. The proposed Sigma Hub includes Sigma Controller as a core management module to unify the multiple USB storages in transaction level layer. Sigma controller can efficiently control transaction packet in Sigma Hub through a USB Storage-Integration algorithms which ensure an integrity for data read and write processes. Consequently, Sigma Hub enables the use of USB storage that is logical unity.

A Study on Socio-economic Investment Effects of Ginger Storage in Artificial Caves (In the Case of Seochun Districts in Chungnam Province) (토굴을 이용한 생강저장의 사회 경제적 투자효과 분석 - 서산지역을 중심으로 -)

  • Lee, Mu Won;Lim, Jae Hwan
    • Korean Journal of Agricultural Science
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    • v.25 no.2
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    • pp.310-320
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    • 1998
  • This study is aimed at identifying the socio-economic effects of storage of ginger in artificial caves. The gingers stored in artificial caves in Seochun, 12 sampled areas, were surveyed to get information on the socio-economic effects. The surveyed data were processed by TSP, Qbasic and B/C Ratio computer programs and analyzed the decision making criteria such as B/C ratio, NPV and IRR. The socio-economic effects of the storages of the gingers are as follows. 1. The storage benefits per ton was showed as 184,050won. 2. Considering 10% of the opportunity cost of capital, the uper limits of investments for the cave storages was analyzed as 6,784 thousand won for ginger. 3. The investment of the natural cave storages was revealed economically feasible considering the decision making criteria as B/C ratio = 1.33, NPV = 35.059 thousand won and IRR = more than 100%. The other socio-economic effects of the ginger storages was expected as ; 1. The cave storages will contribute to increase consumer's and producer's welfare through the control of supply and demand and price stability. 2. Long-term storage of ginger without damaging quality and grades will be made on account of the storage conditions as relatively low temperature, high humidity and indifferent affects from the outside climate. 3. Utilization of the underground space, the caves, for storage will maximize the land use and the sustainable environment considering the mountainous area, two third of the total national land area. 4. Construction costs of the underground storage facilities as caves are cheaper than the ground storage facilities by 15 to 20% in general. In conclusion, the underground space like natural and artificial caves are considered the most suitable for storage of ginger on account of the storage conditions as temperature, humidity and blocking the sun light. Accordingly a study on convenient utilization of new development of artificial caves should be made considering transportation and input-output of the farms. Financial support of the government should be institutionally rearranged for the successful implementation of storing farm products like ginger in natural and man-made caves.

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An Analysis of the Distribution Structure and Logistics System of Light Petroleum Products (석유제품의 유통구조와 물류체계 분석 - 경질제품을 대상으로 -)

  • 이희연;최윤선
    • Journal of the Economic Geographical Society of Korea
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    • v.5 no.1
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    • pp.5-24
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    • 2002
  • The purpose of this study is to analyze the distribution structure and the logistics system of light petroleum products from the spatial perspectives. The consumption structure of petroleum products has been changed since the mid 1980s. The growth rate of consumption for light products has been much faster than those of heavy products. The distribution structure of the petroleum products is hierarchically established by refining companies, agencies, and gas stations. The petroleum products agencies are distributed unevenly over the country, and the number of gas stations per one petroleum agency are very differentiated by the region. The light products are directly transported from refining factories to oil storages and then are carried to gas stations. According to the locational characteristics, oil storages which play a key role in the logistics system are categorized into three type. The first type is demand-oriented oil storages which are located near or in the large cities to supply the light petroleum products. The second type is harbors-oriented oil storages which are located within harbors. The third type is railway-oriented oil storages which are located along railway stations. In this study, the thresholds of one oil storage and one gas station are calculated based on the size of supply territory for each oil storage. The average number of population demand that allow a oil storage to stay in business is 1.9 million and average number of cars are 477,200.

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