• Journal of KIISE:Databases
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• v.31 no.2
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• pp.108-121
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• 2004

In this paper, we propose an enhanced snapshot technique that solves performance degradation when snapshot is initiated for the storage cluster system. However, traditional snapshot technique has some limits adapted to large amount storage shared by multi-hosts in the following aspects. As volume size grows, (1) it deteriorates crucially the performance of write operations due to additional disk access to verify COW is performed. (2) Also it increases excessively the blocking time of write operation performed during the snapshot creation time. (3)Finally, it deteriorates the performance of write operations due to additional disk I/O for mapping block caused by the verification of COW. In this paper, we propose an efficient snapshot technique for large amount storage shared by multi-hosts in SAN Environments. We eliminate the blocking time of write operation caused by freezing while a snapshot creation is performing. Also to improve the performance of write operation when snapshot is taken, we introduce First Allocation Bit(FAB) and Snapshot Status Bit(SSB). It improves performance of write operation by reducing an additional disk access to volume disk for getting snapshot mapping block. We design and implement an efficient snapshot technique, while the snapshot deletion time, improve performance by deallocation of COW data block using SSB of original mapping entry without snapshot mapping entry obtained mapping block read from the shared disk.

• Journal of KIISE:Databases
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• v.35 no.5
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• pp.411-420
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• 2008

The number of XML documents, which are widely used as a standard method for information expression and exchange in the web-based environment, increases rapidly along with the growing production of large XML documents. Many studies have been made to store and retrieve these XML documents on RDBMS, among which Shared Inlining storage method has a higher level of retrieval efficiency. The Shared Inlining method is the technique that analyzes the DTD information and stores the XML document in RDBMS by dividing for each node component. This study proposes the technique to resolve the overlapping problem that occurs in the element with several child nodes in the existing Shared Inlining method. The suggested method stores the XML document in the Shared Inlining structures appropriate to the DTD definition and enhances the accuracy of retrieval.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1327-1330
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• 2003

The internet SCSI(iSCSI) disk has been studied as a storage system which can be directly connected to TCP/IP network. We designed and implemented a shared disk following the iSCSI protocol and providing cache consistency. It is named as intelligent iSCSI(i$^2$SCSI) disk. The i$^2$SCSI disk provides cache consistency of all blocks that belong to the disk using a conventional lease method and it uses 'contiguous blocks-level locking' The prototype of the i$^2$SCSI disk emulator and its client is designed and implemented in Linux 2.4.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.607-612
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• 1993

In this paper, a heuristic procedure is presented which first determines the positions of adding storage tank. Then a nonlinear programming is formulated to obtain their optimum size. Flexible utilization(shared equipment) of storage tank is suggested. The effectiveness of this method is verified by solving two literature problems.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.27-32
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• 2008

The present study has been conducted economic analysis of heat storage type ground source heat pump system(HSGSHP) and normal ground source heat pump (GSHP) which are installed at the same building in the shared an apartment house. Cost items, such as initial cost, annual energy cost and maintenance cost of each system are considered to analyze life cycle cost (LCC) and simple payback period (SPP) with initial cost different are compared. The initial cost is a rule to the Government basic unit cost of production. LCC applied present value method is used to assess economical profit of both of them. Variables used to LCC analysis are prices escalation rate and interest rate mean values of during latest 10 years. The LCC result shows that HSGSHP (1,050,910,000won) is more profitable than GSHP by 68.9% initial cost. And SPP appeared 3.0 year overcome the different initial cost by different annual energy cost.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.4
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• pp.350-357
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• 2002

Optimal control algorithms for the full storage ice cooling system were developed by using a dynamic simulation program. Control algorithms for the storage charging mode were developed for the chiller outlet temperature setpoint control and the chiller capacity control. Control algorithms for the storage discharging mode were developed for the proper mode selection, the storage-only mode control, and the storage-priority chiller-shared mode control. Two different cases of the expected outdoor air temperature profile and the expected cooling load profile were used to analyze the effectiveness of these algorithms. Simulation results show the energy savings and the satisfactory controls of the ice storage system. Therefore, control algorithms developed for this study may effectively be used for the improved control of the ice storage cooling system.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.303-308
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• 1992

In this study, we propose a shared storage system which is more efficient policy than MIS(Mixed Intermediate Storage) policy for relatively rare storage system and can be called CIS(Common Intermediate Storage) policy. Using this strategy, we develop a new completion time algorithm and apply it to two kinds of optimal or near optimal scheduling method; combinatorial search and simulated annealing method. We also extend this strategy to other storage policy, for example MIS policy, with PLC(Programmable Logic Controller) logic and on/off action of electronic valves. It thus can be accepted as a basic form of FMS(Flexible Manufacturing System) for operating various storage policies. Finally we suggest the interlocking block to compansate for the shortcoming of CIS policy, i.e, complication of operation and safety, resulting in a basic batch process automation mode.

• Journal of Korean Library and Information Science Society
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• v.44 no.2
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• pp.267-291
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• 2013

Academic research libraries are seeking a long-term preservation plan for journals for cost-effective stewardship. The emergence of shared print archives has given the library community the opportunity to resolve the problem of the lack of library storage and build a collaborative long-term archiving plan for the print journals. The purpose of this study is to examine Western Regional Storage Trust(WEST), the largest print journal archiving program in North America, and identify their strategies for building a distributed, retrospective print repository service for journals. Based on the analysis, this article will discuss the development of new trends of collaborative library management in a digital age.

• Journal of the Korean housing association
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• v.8 no.1
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• pp.1-12
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• 1997

The purpose of this research is to identify user needs for community space design, especially shared space. and compare them according to social class. Since the shared space concept is new, it will be difficult for residents to familiarize themselves with the new idea. This study used a Small Croup Workshop Panel Method instead of the conventional survey method for this reason The subjects were 6 Panel groups of S people per each group. Bach of the panels included 3consecutive workshops. The results can be summarised as follows. All the residents wanted various kinds of shared spaces for everyday living and leisure activity While there were generally great similarity regardless of resident's sub characteristics, some founed distintively dissimilar. The residents of 20s pyung apartment wanted day-care center, multi Purpose room for meeting and family events, library, study room, sports facilities, and cultural center in order. The shared spaces that residents of 30s pyung apartment wanted were library. study room. common dining, sports facilities. and cultural center in order. The residents of 50s pyung apartment wanted library, study room. multi purpose room, common storage, sports facilities. and cultural center in order. These findings imply some diverse plans instead of uniform ones are to be deliberately considered, This results can be usefully applied to develop new collective housing for different social class residents.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1633-1636
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• 2003

In this paper, we developed the scheme to grow to use newly added disk space without having to kill the application, unmount file system. This scheme, called online resizing, can resize the file system layout with the advent of Logical Volume Manager. The online resizing scheme is designed and implemented in linux cluster system where multiple hosts share the disk data in storage area network environment. It is incorporated with SANfs shared file system and can perform resizing technique with SANfs-VM volume manager. The experimental result shows that it can maximize the availability and capacity of the SANfs system which are important for modem servers where must not lose their customer.