• Title/Summary/Keyword: Storage Service

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Estimating the storage space requirement of a container terminal considering the variance of a containership's load size (본선 작업물량의 변동을 고려한 컨테이너 터미널의 장치공간 소요량 추정)

  • Bae, Jong-Wook;Park, Byung-In
    • Journal of Navigation and Port Research
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    • v.31 no.5 s.121
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    • pp.361-368
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    • 2007
  • The storage space requirement is a very important decision variable which determines the storage capacity of a container terminal. Generally, the storage space requirement is dependent upon such factors as ship headway, allowable dwell time of containers, loading/winding time per ship, and so on. Until now, the storage space requirement is estimated under the assumption that the factors are deterministic in several studies. However, this study proposes how to estimate a storage space requirement satisfying the required service level under the assumption that a containership's load size is probabilistic. Numerical experiments, which use a simulation show that the proposed method can estimate more adequately the storage space requirement than other methods under a probabilistic environment.

FlashEDF: An EDF-style Scheduling Scheme for Serving Real-time I/O Requests in Flash Storage

  • Lim, Seong-Chae
    • International Journal of Internet, Broadcasting and Communication
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    • v.10 no.3
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    • pp.26-34
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    • 2018
  • In this paper, we propose a scheduling scheme that can efficiently serve I/O requests having deadlines in flash storage. The I/O requests with deadlines, namely, real-time requests, are assumed to be issued for streaming services of continuous media. Since a Web-based streaming server commonly supports downloads of HTMLs or images, we also aim to quickly process non-real-time I/O requests, together with real-time ones. For this purpose, we adopt the well-known rate-reservation EDF (RR-EDF) algorithm for determining scheduling priorities among mixed I/O requests. In fact, for the use of an EDF-style algorithm, overhead of task's switching should be low and predictable, as with its application of CPU scheduling. In other words, the EDF algorithm is inherently unsuitable for scheduling I/O requests in HDD storage because of highly varying latency times of HDD. Unlike HDD, time for reading a block in flash storage is almost uniform with respect to its physical location. This is because flash storage has no mechanical component, differently from HDD. By capitalizing on this uniform block read time, we compute bandwidth utilization rates of real-time requests from streams. Then, the RR-EDF algorithm is applied for determining how much storage bandwidth can be assigned to non-real-time requests, while meeting deadlines of real-time requests. From this, we can improve the service times of non-real-time requests, which are issued for downloads of static files. Because the proposed scheme can expand flexibly the scheduling periods of streams, it can provide a full usage of slack times, thereby improving the overall throughput of flash storage significantly.

Design And Implementation of Linux Based Parallel Media Stream Server System (리눅스 기반의 고성능 병렬 미디어 스트림 서버 설계 및 구현)

  • 김서균;김경훈;류재상;남지승
    • The KIPS Transactions:PartA
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    • v.8A no.4
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    • pp.287-292
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    • 2001
  • Multimedia service systems should have efficient capacity to serve the growing clients and new data. In the general streaming services, users can endure the small amount of time delay at the beginning of service. But they want to have good quality of service. A streaming server tries to transfer video files to clients from a repository of files in real time. The server must guarantee concurrent and uninterrupted delivery of each video stream requested from clients. To achieve its purpose, many stream servers adopt multi-processors, sufficient memory, and RAID or SAN in their systems. In this paper, we propose a Linux-based parallel media streaming server. It is superior to the other systems in the storing structure, fault-tolerance, and service capacity. Since this system supports the web interlace, users can operate easily through the www. This system uses unique striping policy to distribute multimedia files into the parallel storage nodes. If a service request occurs, each storage node transmits striped files concurrently to the client. Its performance is better than the single media streaming service because of the parallel architecture.

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Evaluation of Canister Weld Flaw Depth for Concrete Storage Cask (콘크리트 저장용기의 캐니스터 용접부 결함깊이 평가)

  • Moon, Tae-Chul;Cho, Chun-Hyung;Jung, Sung-Hun;Lee, Young-Oh;Jung, In-su
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.1
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    • pp.91-99
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    • 2017
  • Domestically developed concrete storage casks include an internal canister to maintain the confinement integrity of radio-active materials. In this study, we analyzed the depth of flaws caused by loads that propagate canister weld cracks under normal, off-normal and accident conditions, and evaluated the maximum allowable weld flaw depth needed to secure the structural integrity of the canister weld and to reduce the welding time of the internal canister lid of the concrete storage cask. Structural analyses for normal, off-normal and accident conditions were performed using the general-purpose finite element analysis program ABAQUS; the allowable flaw depth was assessed according to ASME B&PV Code Section XI. Evaluation results revealed an allowable canister weld flaw depth of 18.75 mm for the concrete storage cask, which satisfies the critical flaw depth recommended in NUREG-1536.

Change of Free Amino Acid and Nucleotide Compound of Puffer Fish Fillet under Storage Condition (저장조건에 따른 복어육의 유리아미노산 및 핵산 화합물의 변화)

  • Mun, Seung-Kweon;Sung, Ki-Hyup;Yoo, Seung-Seok
    • Korean journal of food and cookery science
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    • v.28 no.3
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    • pp.249-255
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    • 2012
  • The objectives of this study were to evaluate the physicochemical characteristics of puffer fish under storage conditions. Free amino acids were identified in the order of taurine > alanine > lysine > leucine > glutamic acid > valine. Glutamic acid, lysine, histidine, arginine, proline, and aspartic acid increased over time and with increased temperature, and valine and tyrosine were affected by temperature. ATP decreased dramatically during 36 h of storage at $4^{\circ}C$, 24 h of storage at $12^{\circ}C$, and 16 h of storage at $20^{\circ}C$. IMP reached its highest level when puffer fish was stored for 36 h at 4 and $12^{\circ}C$ and 24 h at $20^{\circ}C$, and hypoxanthine levels grew steeply at 60 h at $4^{\circ}C$, 24 h at $12^{\circ}C$ and 20 h at $20^{\circ}C$. In terms of K value, the puffer fish was available for sliced raw fish within 60 h at $4^{\circ}C$, 24 h at $12^{\circ}C$ and 12 h at $20^{\circ}C$, and the fish can be taken in after cooking within 72 h at $4^{\circ}C$ and $12^{\circ}C$ and 36 h at $20^{\circ}C$. The physicochemical quality characteristics showed that puffer fish is available for sliced raw fish within 36 h at $4^{\circ}C$, 16 h at $12^{\circ}C$ and 12 h at $20^{\circ}C$, and that the fish can be taken after cooking within 72 h at $4^{\circ}C$ and $12^{\circ}C$ and 36 h at $20^{\circ}C$.

The Effects of SPI(Soybean Protein Isolate) on Retrogradation in Jeung-pyun (분리대두단백질이 첨가된 증편의 저장성에 관한 연구)

  • Hong, Geum-Ju;Kim, Myung-Hee;Kim, Kang-Sung
    • Korean journal of food and cookery science
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    • v.24 no.3
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    • pp.304-311
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    • 2008
  • This study examined Jeung-pyun(JP) Retrogradation in samples containing 3% whole protein, 7S protein, or 11S protein(w/w) that were stored at $4^{\circ}C$ for 6, 12, 24 and 72 hr. Rheometery and differential scanning calorimetry(DSC) were used in the analysis. The pH of the dough decreased during the fermentation process, but it increased after steaming. The JP prepared with soybean protein isolate(SPI) had higher pH than the control group. During storage the textural characteristics of the JP showed effects according to the additions of SPI. After 6 hr of storage, the JP samples containing soybean flour, whole protein, 7S protein, and 11S protein had lower hardness valuse. From 4 hr to 12 hr, higher springiness values were found in the samples containing whole protein, 7S protein and 11S protein. At 0 hr, the control group had the highest cohesiveness value, but after 24 hr it presented the lowest value. For gumminess, after 6 hr of storage, the control group offered the lowest value. Whereas after 12 hr of storage the whole protein group showed the highest value, and at 24 hr, the whole protein, 7S protein, and 11S protein groups had higher values. According to the DSC results, the 11S protein group had lower enthalpy values(${\bigtriangleup}H$) suggesting that adding 11S protein to JP might improve starch retrogradation. After 72 hr of storage, the control group had the highest onset temperature($T_{o}$) and peak temperature($T_{p}$) whereas the 7S and 11S protein JP samples had higher conclusion temperatures($T_{c}$). Therefore, based on the different analysis result between the control and treatment groups, the addition of SPI to Jp had effects on retrogradation.

Effects of an ice pack and sulfur generating pad treatment for home delivery on the quality of 'Duke' blueberry fruits

  • Lim, Byung-Seon;Choi, Mi-Hee;Lee, Jin-Su
    • Korean Journal of Agricultural Science
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    • v.45 no.4
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    • pp.811-821
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    • 2018
  • This study focused on the improvement of blueberry delivery service using pre-cooled ice and $SO_2$ pads to prevent an increase in the fruit temperature as well as decay. To maintain the fruit quality during low temperature storage, the effect of a $SO_2$ pad and modified atmosphere packaging was also examined. Harvested blueberries were precooled at $15^{\circ}C$, sorted, and packaged. And the fruits were placed in a similar environment as that for the parcel service. Part of the fruits were stored at $0^{\circ}C$ for long term storage. The air temperature in the delivery box increased along with an increase in the simulated delivery time regardless of the treatment. However, the rate of temperature increase was lower in the ice pad treatment. No significant difference was not found after 48 h. The oxygen concentration in the box ranged between 10.5 - 14.5% in the ice pad treatment, which was higher than that of the untreated control (7.5 - 11.9%) whereas the $CO_2$ concentration was lower in the ice pad treatment. No differences were found in the occurrence of off-flavor, decay, and sensory quality loss during the 48 hours of the parcel service simulation. The combined treatment of the $SO_2$ pad and modified atmosphere packaging (MAP) using a perforated film increased the shelf-life of the blueberry fruits, the overall quality such as firmness, and the soluble solid content was not different between the treatments except for the decay incidence. No decayed fruit was found in the combined treatment. However, the percentage of decayed fruit in the control was 25% on day 15 of storage and 75% on day 33 of storage, respectively.

Implementation of Hardware RAID and LVM-based Large Volume Storage on Global Data Center System of International GNSS Service

  • Lee, Dae-Kyu;Cho, Sung-Ki;Park, Jong-Uk;Park, Pil-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1553-1557
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    • 2005
  • High performance and reliability of the storage system to handle a very large amount of data has been become very important. Many techniques have been applied on the various application systems to establish very large capacity storage that satisfy the requirement of high I/O speed and physical or logical failure protection. We applied RAID and LVM to construct a storage system for the global data center which needs a very reliable large capacity storage system. The storage system is successfully established and equipped on the latest Linux application server.

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Implementation of Group Office System Based on Internet (인터넷 기반의 그룹 오피스 시스템 구현)

  • Kim Kyoung-Rok;Song Seok-Il;Kwak Yoon-Sik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.3
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    • pp.540-546
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    • 2005
  • In this paper, we design and implement a distributed web-storage and a group office system based on the distributed web-storage. It is easier to customize the proposed group office according to user's demands than existing web-based applications. Our proposed web-storage is distributed system which consists of multiple storage servers. The web-storage provides storage with considering the user's location so as to provide fast storage service.

An Approach to Determining Storage Capacity of an Automated Storage/Retrieval System under Full Turnover-Based Policy (물품회전율을 기준으로 한 저장정책하에서 자동창고의 저장규모 결정방법)

  • Lee, Moon-Kyu
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.4
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    • pp.579-589
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    • 1998
  • Full turnover-based storage policy (FULL) is often used to minimize the travel time needed to perform storage/retrieval operations in automated storage/retrieval systems (AS/RSs). This paper presents an approach for determining the required storage capacity for a unit load AS/RS under the FULL. An analytic model is formulated such that the total cost related to storage space and space shortage is minimized while satisfying a desired service level. To solve the model, some analytic properties are derived and based on them, an iterative search algorithm which always generates optimal solutions is developed. To illustrate the validity of the approach, an application is provided when the standard economic-order-quantity inventory model is used.

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