• Title/Summary/Keyword: RAID5

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Improvement of Motion Accuracy Using Transfer Function in Linear Motion Bearing Guide (전달함수를 이용한 직선베어링 안내면의 운동정밀도 향상)

  • Kim, Kyung-Ho;Park, Chun-Hong;Lee, Hu-Sang;Kim, Seung-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.6
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    • pp.77-85
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    • 2002
  • An analysis method which calculates corrective machining information for improving the motion accuracy of linear motion guide Is proposed in this paper. The method is composed of two algorithms. One is the algorithm fur prediction of the motion errors from rail form error. The other is the algorithm for prediction of rail form error from the motion errors of table. Transfer function is utilized in each algorithm, which represents the ratio of bearing reaction force variation to unit magnitude of spatial frequencies of raid from error. As the corrective machining information is acquired from the measured motion errors of table, the method has a merit not to measure rail form error directly. Validity of the method is verified both theoretically and experimentally. By applying the method, linear motion error of test equipment is reduced from 5.97$\mu$m to 0.58$\mu$m, and reduced from 32.78arcsec to 6.21 arcsec in case of angular motion error. From the results, it is confirmed that the method is very effective to improve the motion accuracy of linear motion guide.

Design And Performance Evaluation of Fault-Tolerant Continuous Media Storage System Based on $PRR_gp$ ($PRR_gp$ 기반 결함허용 연속 매체 저장시스템의 설계와 성능평가)

  • O, Yu-Yeong;Kim, Seong-Su
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.4
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    • pp.1290-1298
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    • 2000
  • Multimedia Systems such as VOD(Video On Demand) and MOD (Multimedia On Demand) need to support continuous media operations which are randomly called by concurrent users and require that stored media be accessed in real-tim. To satisfy such a requirements, disk arrays consisting of multiple disks are generally used as storage systems. Under the real-time environments to provide users with accessing continuous media in the parallel and concurrent manner, storage systems should be able to deal with user requests independently. In this paper, we present a new fault-tolerant continuous media storage system called PADA(PRR\ulcorner bAsed Disk Array), which is based on a PRR\ulcorner (Prime Round Robin with Grouped Parties) disk placement scheme with enhanced reliability nd load-balancing. We have compared and evaluated the storage space overhead for fault-tolerance, the reliability of diks array systems, the degree of disk load0-balancing, the demanded buffer space, the maximum number of users being capable of supporting and the fault recovery overhead for PADA, RAID 5 and Declustered storage systems. According to the results, PADA is the best among them in that PADA satisfies load-balancing more effectively and servces more user in case of arbitrary-rate retrievals.

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High-Performance VOD server based on storage access scheduling and double buffer (스토리지 접근 스케쥴링과 더블 버퍼구조 기반 VOD 서버의 고성능화)

  • Kim, Cheon-Seog;Ji, Mi-Kyong;Yoon, Jeong-Hyun;Kim, Kyu-Seok
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.11a
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    • pp.403-405
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    • 2009
  • 통방융합 환경에서 Killer 서비스로 각광을 받고 있는 VOD(Video On Demand)서비스에서 I/O 병목현상은 VOD 서버의 오 동작 및 성능 저하의 주요 원인이 되고 있다. 본 논문에서는 이런 I/O 병목 현상을 개선하여 입출력 효율이 좋은 고성능 VOD 솔루션을 제안한다. 제안된 솔루션은 대용량 더블 버퍼를 구성하여 하나의 버퍼로 클라이언트에 데이터를 전송하고 있는 사이에, 나머지 다른 버퍼에서 스토리지에서 전송되는 데이터를 버퍼에 저장 하여, 디스크 접근 시 한번에 보다 많은 데이터를 읽음으로써 연속적인 정보를 가져올때 빈번하게 하드디스크의 접근을 줄임으로서 끊김없는 전송을 가능하게 한다. 또한 다수의 사용자가 동시 접근 시 데이터 충돌을 방지하고, 스토리지에 순차적으로 연속 접근하도록 접근 발생 시간에 따라 우선 순위 인덱스를 할당하고 회수하도록 스토리지 접근 스케쥴러를 고안 하였다. 제안된 솔루션의 유효성을 검증하기 위해 SD급 콘텐츠에 대해 솔루션의 Throughoutput 처리량을 벤치마킹 테스트로 검증을 하였다. 테스트 결과 MPEG-2 SD급 영상에대해 Raid 5에서 최대 1000 스트리밍을 전송 할 수 있음을 확인 하였다.

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Development of Guidelines for Raid Response to Acute Deteriorating of Hospitalized Patients (입원환자의 급성 악화 신속대응 가이드라인 개발)

  • Lee, Ha-Nui;Park, Jeong-Sook
    • The Journal of the Korea Contents Association
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    • v.22 no.10
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    • pp.359-373
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    • 2022
  • The purpose of this study was to develop evidence-based practice guideline for rapid response to acute deterioration of hospitalized patients. The guideline was developed according to the Clinical Practice Guideline Adaptation Manual. and evaluated using AGREE II tool. The guidelines were checked content validation by an expert group, final 130 recommendations in 5 sections including management, recognition, activation, response, and evaluation. The average of the overall practical application to the guidelines was 4.41±0.78 out of 5, which showed high applicability in clinical work.

Analysis on Playing Pattern of Mobile RPG's Combat Contents - Focus on - (모바일 역할수행 게임 전투 콘텐츠의 플레이 패턴 연구 - <세븐 나이츠>를 중심으로 -)

  • Lyou, Chul-Gyun;Kim, HwaHyun
    • Journal of Korea Game Society
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    • v.16 no.5
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    • pp.69-78
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    • 2016
  • A sense of oneness between a player and an avatar is more emphasized than role-playing itself in Korean RPG playing. Because of this tendency, the main contents of smart phone-based mobile RPG are mainly focus on combat. As PvP occurs more frequently in mobile RPG, playing experiences are diversified from sensitive control to simple repetition. Also, the auto-combat function offered in game system ingenerates funs from testing a mental model that a player statistically sets before playing. This paper analyzes the process of generating fun in mobile RPG based on Ralph Koster's Game Grammar theory. is selected as subject of this analysis. The pattern of mobile RPG playing is dichotomized : automation of producing materials and concentration on raid and PvP contents.

Behavior of piled rafts overlying a tunnel in sandy soil

  • Al-Omari, Raid R.;Al-Azzawi, Adel A.;AlAbbas, Kadhim A.
    • Geomechanics and Engineering
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    • v.10 no.5
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    • pp.599-615
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    • 2016
  • The present research presents experimental and finite element studies to investigate the behavior of piled raft-tunnel system in a sandy soil. In the experimental work, a small scale model was tested in a sand box with load applied vertically to the raft through a hydraulic jack. Five configurations of piles were tested in the laboratory. The effects of pile length (L), number of piles in the group and the clearance distance between pile tip and top of tunnel surface (H) on the load carrying capacity of the piled raft-tunnel system are investigated. The load sharing percent between piles and rafts are included in the load-settlement presentation. The experimental work on piled raft-tunnel system yielded that all piles in the group carry the same fraction of load. The load carrying capacity of the piled raft-tunnel model was increased with increasing (L) for variable (H) distances and decreased with increasing (H) for constant pile lengths. The total load carrying capacity of the piled raft-tunnel model decreases with decreasing number of piles in the group. The total load carrying capacity of the piles relative to the total applied load (piles share) increases with increasing (L) and the number of piles in the group. The increase in (L/H) ratio for variable (H) distance and number of piles leads to an increase in piles share. ANSYS finite element program is used to model and analyze the piled raft-tunnel system. A three dimensional analysis with elastoplastic soil model is carried out. The obtained results revealed that the finite element method and the experimental modeling are rationally agreed.

Flash-Conscious Storage Management Method for DBMS using Dynamic Log Page Allocation (동적 로그 페이지 할당을 이용한 플래시-고려 DBMS의 스토리지 관리 기법)

  • Song, Seok-Il;Khil, Ki-Jeong;Choi, Kil-Seong
    • Journal of Advanced Navigation Technology
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    • v.14 no.5
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    • pp.767-774
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    • 2010
  • Due to advantages of NAND flash memory such as non-volatility, low access latency, low energy consumption, light weight, small size and shock resistance, it has become a better alternative over traditional magnetic disk drives, and has been widely used. Traditional DBMSs including mobile DBMSs may run on flash memory without any modification by using Flash Translation Layer (FTL), which emulates a random access block device to hide the characteristics of flash memory such as "erase-before-update". However, most existing FTLs are optimized for file systems, not for DBMSs, and traditional DBMSs are not aware of them. Also, traditional DBMSs do not consider the characteristics of flash memory. In this paper, we propose a flash-conscious storage system for DBMSs that utilizes flash memory as a main storage medium, and carefully put the characteristics of flash memory into considerations. The proposed flash-conscious storage system exploits log records to avoid costly update operations. It is shown that the proposed storage system outperforms the state.

Efficacy of Aloclair$^{TM}$ for Treatment of Intraoral Ulcer Caused by Orthodontic Appliance (교정장치에 의해 유발된 구내궤양 치료에 대한 Polyvinylpyrrolidone-sodium hyaluronate (Aloclair$^{TM}$)의 임상적 효과)

  • Lee, Ju-Hee;Lee, Sang-Min;Park, In-Young
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.2
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    • pp.109-118
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    • 2012
  • This experimental study was undertaken to evaluate the efficacy of polyvinylpyrrolidone-sodium hyaluronate(Aloclair$^{TM}$) in decreasing pain in orthodontic procedures. A total of 60 patients who were use Aloclair$^{TM}$ ordered to were included. These patients were categorized by 3 cases; 1. Patients who were bonded with their first brackets. 2. Patients who were in pain with additional appliance such as anchorage devices. 3. Patients who got ulcer caused by appliances. We collected information about pain and assessed it using visual analogue scale. According to questionnaire, it took 3.5 min. for pain to subside and pair relief durated for 2.7 hours. Most patients in the study reported rapid pain relief and found Aloclair$^{TM}$ easy and pleasant to use than wax. Accordingly Aloclair$^{TM}$ provided raid relief of resting and provoked ulcer pain.

The Design and Implementation of the Reliable Network RAM using Compression on Linux (리눅스에서 압축을 이용한 안정적인 네트웍 램의 설계 및 구현)

  • 황인철;정한조;맹승렬;조정완
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.5_6
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    • pp.232-238
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    • 2003
  • Traditional operating systems use a virtual memory to provide users with a bigger memory than a physical memory. The virtual memory augments the insufficient physical memory by the swap device. Since disks are usually used as the swap device, the cost of a page fault is relatively high compared to the access cost of the physical memory. Recently, numerous papers have investigated the Network RAM in order to exploit the idle memory in the network instead of disks. Since today's distributed systems are interconnected with high-performance networks, the network latency is far smaller than the disk access latency In this paper we design and implement the Network RAM using block device driver on Linux. This is the first implementation of the Network RAM on Linux. We propose the new reliability method to recover the page when the other workstation's memory is damaged. The system using the Network RAM as the swap device reduces the execution time by 40.3% than the system using the disk as the swap device. The performance results suggest that the new reliability method that use the processor more efficiently has the similar execution time with others, but uses smaller server memory and generates less message traffic than others.

Visual Image of a Yangbanxi (Chinese "Model Play") Dating from the Cultural Revolution Period in China - With the Focus on Images of Revolutionary Heroes in the Beijing Opera The Red Lantern (중국 문혁기 모범극(樣板戱)의 시각이미지 - <홍등기(紅燈記)>의 혁명영웅상을 중심으로)

  • Moon, Jung-Hee
    • The Journal of Art Theory & Practice
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    • no.5
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    • pp.197-215
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    • 2007
  • Yangbanxi("model plays") symbolize the Cultural Revolution(1966~1976) in China. The Eight Model Revolutionary Works include five Chinese Modern Peking Operas, namely, Taking Tiger Mountain by Strategy(智取威虎山), Harbor(海港), Shaijabang(沙家浜), The Red Lantern(紅燈記), and Raid on the White Tiger Regiment ; (奇襲白虎團), ballets such as The Red Detachment of Women(紅色娘子軍) and The White-Haired Girl(白毛女) ; and a symphony: Shajiabang(沙家浜). On April 24, 1967, Chinese leaders, including Mao Zedong, saw a performance of The White-Haired Girl. Yanbanxi was performed in Beijing between May 24 and June 15 the same year. The Red Lantern was designated as a work for the proletarian classes by Jiang Qing(Mao Zedong's third wife and the most influential woman in China) and spread nationwide. It was also made into a film to be enjoyed by many people. The modern Chinese operas went a long way in their creation of visual images of revolutionary heroes. The Red Lantern, in particular, came to be regarded as the most representative revolutionary opera. In the course of such a process, Jiang Qing used Yangbanxi as a political tool for compelling the people to worship and pledge their allegiance to Mao in an effort to turn the Cultural Revolution into a class struggle on behalf of her husband. During the Cultural Revolution period, artists were made to associate with workers, farmers and soldiers based on the idea of advocating revolutionary arts for the proletarian classes. The characters in The Rend Lantern were portrayed as heroes from the proletarian classes according to the demands of the era. Chinese leaders set forth the principles of artistic expression, stressing three important factors: politics, heroes, and heroic acts, which were to be applied to all the visual arts, including Yangbanxi. This paper attempts to present a new view of fine arts during the Cultural Revolution in China by focusing on the productive significance of a leading style of a specific era in the past. To that end, this paper sheds light on products made in conformance with political instructions, stressing the importance of revolutionary heroes in The Red Lantern.

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