• Title/Summary/Keyword: Local I/O

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Optimization and Stabilization of Satellite Data Distributed Processing System (위성 데이터 분산처리 시스템 최적화 및 안정화)

  • Choi, Yun-Soo;Lee, Won-Goo;Lee, Min-Ho;Kim, Sun-Tae;Lee, Sang-Hwan
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.11
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    • pp.13-21
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    • 2013
  • The goal of this paper is to provide performance improvement and stability for satellite data correction of some distortions due to cloud or radiance through distributed processing on cluster. To do this, we proposed and implemented SGE(Sun Grid Engine) based distributed processing methods using local storages and a status table. In the verification, the experiment result revealed that the proposed system on seven nodes improved the processing speed by 138.81% as compare to the existing system and provided good stability as well. This result showed that the proposed distributed processing work is more appropriate to process CPU bound jobs than I/O bound jobs. We expect that the proposed system will give scientists improved analysis performance in various fields and near-real time analysis services.

Development of a Distributed File System for Multi-Cloud Rendering (멀티 클라우드 렌더링을 위한 분산 파일 시스템 개발 )

  • Hyokyung, Bahn;Kyungwoon, Cho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.1
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    • pp.77-82
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    • 2023
  • Multi-cloud rendering has been attracting attention recently as the computational load of rendering fluctuates over time and each rendering process can be performed independently. However, it is challenging in multi-cloud rendering to deliver large amounts of input data instantly with consistency constraints. In this paper, we develop a new distributed file system for multi-cloud rendering. In our file system, a local machine maintains a file server that manages versions of rendering input files, and each cloud node maintains a rendering cache manager, which performs distributed cooperative caching by considering file versions. Measurement studies with rendering workloads show that the proposed file system performs better than NFS and the uploading schemes by 745% and 56%, respectively, in terms of I/O throughput and execution time.

Influence of N-Fertilization on Growth , Yield and Nutrient Quality of Forage Job`s Tears [ Coix lachryma-jobi L. var. mayeur STAPF ] (청예 사초용 율무의 질소시비수준이 생육특성과 사료성분에 미치는 영향)

  • 안계주;권병선;김찬호
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.2
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    • pp.127-131
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    • 1992
  • To find out the optimum fertilizer levcl for Job's Tears, Seungju local cultivar, experiment with six fertilizer levels was conducted on the experimental field of forage crop in Sunchon National University from Apr. 1989 to Aug. 1990. The results obtained were summarized as follows: I .Raising nitrogen(N) application rate up to 13.5 kg/lOa increased dry matter yield linearly. However, at high N application rate, 18 kg/lOa, plants were too leafy and parts of leaves and lodging were decreased. so that dry matter yield was decreased.2. The optimum application rate of fertilizers turned out to be 13.5-6-6 kg/lOa of $P_2O_5$, $K_2O$. Content of crude protein, yield of fresh and dry matter were the highest and that of crude fiber such as NDF. ADF and cellulose were the lowest at this rate.

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A Case Study on the Implementation of Tele-Operation Robot Hand by Learning Factory based Technology Convergence Education (러닝팩토리기반 기술융합교육을 통한 텔리 오퍼레이션 로봇핸드 구현 사례 연구)

  • Hong, Chang-Ho;Lee, Jung-Hoon;Kim, Hyung-O
    • Journal of Practical Engineering Education
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    • v.10 no.2
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    • pp.113-118
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    • 2018
  • The most important thing in vocational education and training is to enhance students' interest and understanding of the whole process of the production site. In this paper, we present a case on the implementation of tele-operation robot hand by learning factory based technology convergence education. It also suggests some points to be taken when applying the learning factory in the future curriculum. In order to implement the tele-operation robot hand, it is necessary to support the compulsory subjects of university level courses in domestic curriculum such as mechanic design, motor control, local communication implementation, sensing and feedback control. The educational research presented in this paper guides the students with the skills they need and understands the skills through self-study and practice, and implements the final products. This study will be useful as a base data when introducing the training process of training factory in the future.

Design and Implementation of a Metadata Structure for Large-Scale Shared-Disk File System (대용량 공유디스크 파일 시스템에 적합한 메타 데이타 구조의 설계 및 구현)

  • 이용주;김경배;신범주
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.1
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    • pp.33-49
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    • 2003
  • Recently, there have been large storage demands for manipulating multimedia data. To solve the tremendous storage demands, one of the major researches is the SAN(Storage Area Network) that provides the local file requests directly from shared-disk storage and also eliminates the server bottlenecks to performance and availability. SAN also improve the network latency and bandwidth through new channel interface like FC(Fibre Channel). But to manipulate the efficient storage network like SAN, traditional local file system and distributed file system are not adaptable and also are lack of researches in terms of a metadata structure for large-scale inode object such as file and directory. In this paper, we describe the architecture and design issues of our shared-disk file system and provide the efficient bitmap for providing the well-formed block allocation in each host, extent-based semi flat structure for storing large-scale file data, and two-phase directory structure of using Extendible Hashing. Also we describe a detailed algorithm for implementing the file system's device driver in Linux Kernel and compare our file system with the general file system like EXT2 and shard disk file system like GFS in terms of file creation, directory creation and I/O rate.

CONVERTING FROM ORAL SEDATION TO INTRAVENOUS SEDATION USING TOPICAL ANESTHETICS ON SKIN AFTER ORAL SEDATION FAILURE (경구진정 실패 후 피부 도포마취제를 사용한 정주진정으로의 전환 치료)

  • Lee, Eun-Hui;Kim, Seung-Oh;Kim, Jong-Soo;Yoo, Seung-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.2
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    • pp.213-217
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    • 2010
  • The use of chloral hydrate and hydroxyzine for oral sedation is most effective in children aged less than 36 months and weighing less than 15 kg. Children who do not belong to this category may show frequent movements due to shallow sedation level, and it can lead to sedation failures. One of the solutions to such sedation failure is conversion to deeper sedation. But, it is not so much of an option, since inhalation anesthetics and devices are required. In this case, conversion from oral sedation to intravenous sedation was successfully achieved without causing injection pain while searching for an intravenous route, by using EMLA cream (Eutectic Mixture of Local Anesthesia). A patient aged 46 months and weighing 15 kg visited the Pediatric Department of Dankook University Dental Hospital. Treatment under TSD(Tell Show Do) was offered, but due to the parent's request, oral sedative measures were taken. Considering prompt converting from oral sedation to iv sedation in case the oral sedation fails, EMLA cream was apllied preemptively. Adequate sedation level could not be achieved after 90 minutes of oral administration, therefore, under the parent's consent, intravenous route was prepared after conscious sedation by $N_2O-O_2$. During treatment, $ETCO_2$, $SPO_2$ and heart rate was monitored every 5 minutes. The patient showed stable vital signs and did not show any movements. The whole procedure took two and a half hours in total, and the treatment was completed without any adverse effects.

THE STUDY OF CORRELATION WITH CYCLOSPORIN A INDUCED GINGIVAL OVERGROWTH AND LOCAL FACTORS (Cyclosporin A 유도 치은증식과 국소적 요인과의 상관관계에 대한 연구)

  • Ko, Eun-Ah;Yoo, Hyung-Keun;Shin, Hyung-Shik
    • Journal of Periodontal and Implant Science
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    • v.25 no.1
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    • pp.14-23
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    • 1995
  • Cyclosporin A is a powerful immunosuppressive agent commonly used for patients receiving organ transplants. Like phenytoin and the calcium channel blockers, the drug is associated with gingival overgrowth. The purpose of this study was to compare the correlation with gingival overgrowth score and clinical indices(i.e, : plaque index, papillary bleeding index, probing depth) and correlation with gingival overgrowth score and microorganism distribution in use of phase contrast microscope. After renal tranplant, taking cyclosporin A 40 patients participating in this investigation. Post - transplatation cyclosporin medication period was average $17.53{\pm}15.75$ months. In previous study reported that gingival overgrowth is an adverse side - effects seen in about 25-81% of patient taking cyclosporin A. The results were as follows : 1. Gingival overgrowth prevalence in taking cyclosporin A patients was 77.5%. Prevalence rate of region was anterior region(26 teeth, 55.3%), molar region(14 teeth, 29.8%), premolar region(7 teeth, 14.8%) in turns. Gingival overgrowth score by Angelopoulos & Goaz method was molar region($1.56{\pm}0.81$), anterior region($1.52{\pm}0.75$), premolar region($1.14{\pm}0.90$) in turns. 2. Medication period was not correlation with gingival overgrowth score. 3. Clinical indices and gingival overgrowth score were as follows. 1) Plaque index and gingival overgrowth score was significantly correlated(p

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The Characteristics of Temporal and Spatial Distribution of Surface Ozone Concentration in Jeju Island (제주지역 지표 오존 농도의 시.공간적 분포 특성)

  • Lee, Gi Ho;Kim, Dae Jun;Heo, Cheol Gu
    • Journal of Environmental Science International
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    • v.13 no.4
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    • pp.377-387
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    • 2004
  • This study has been performed to clarify the characteristics of temporal and spatial distribution of surface ozone concentration over Jeju Island, one of the cleanest areas in Korea with low emissions of air pollutants. Ozone data are monitored at four sites in Jeju Island. These monitoring sites are located at two urban area(referred to Ido and Donghong), coastal area(Gosan site) and forest site(Chuna site). Ozone data has been routinely collected at these sites for the late four years. The patterns of seasonal cycle of ozone concentrations at all stations show the bimodal with the peaks on spring and autumn and a significant summer minimum. However, the patterns of diurnal variations at rural station, i.e., Gosan and Chuna sites are considerably different to those at urban stations such as Ido and Donghong sites. The patterns of $\DeltaO_3$ variations are very similar with those of monthly mean ozone concentrations and $\DeltaO_3$ values are exceeded 30 ppb, at urban stations. This may be that urban stations are more influenced by local photochemical reactions rather than rural stations. In order to assess the potential roles of meteorological parameters on ozone formation, the meteorological parameters, such as radiation, temperature, and wind are monitored together with ozone concentrations at all stations. The relationships of meteorological parameters to the corresponding ozone concentration are found to be insignificant in Jeju Island. However, at Gosan and Donghong stations, when the sea breeze blew toward the station, the ozone concentration is considerably increased.

A PROPERTY OF COFUNCTORS SF(X,A)

  • So, Kwang Ho
    • Kyungpook Mathematical Journal
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    • v.13 no.2
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    • pp.235-240
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    • 1973
  • A k-dimensional vector bundle is a bundle ${\xi}=(E,P,B,F^k)$ with fibre $F^k$ satisfying the local triviality, where F is the field of real numbers R or complex numbers C ([1], [2] and [3]). Let $Vect_k(X)$ be the set consisting of all isomorphism classes of k-dimensional vector bundles over the topological space X. Then $Vect_F(X)=\{Vect_k(X)\}_{k=0,1,{\cdots}}$ is a semigroup with Whitney sum (${\S}1$). For a pair (X, A) of topological spaces, a difference isomorphism over (X, A) is a vector bundle morphism ([2], [3]) ${\alpha}:{\xi}_0{\rightarrow}{\xi}_1$ such that the restriction ${\alpha}:{\xi}_0{\mid}A{\longrightarrow}{\xi}_1{\mid}A$ is an isomorphism. Let $S_k(X,A)$ be the set of all difference isomorphism classes over (X, A) of k-dimensional vector bundles over X with fibre $F^k$. Then $S_F(X,A)=\{S_k(X,A)\}_{k=0,1,{\cdots}}$, is a semigroup with Whitney Sum (${\S}2$). In this paper, we shall prove a relation between $Vect_F(X)$ and $S_F(X,A)$ under some conditions (Theorem 2, which is the main theorem of this paper). We shall use the following theorem in the paper. THEOREM 1. Let ${\xi}=(E,P,B)$ be a locally trivial bundle with fibre F, where (B, A) is a relative CW-complex. Then all cross sections S of ${\xi}{\mid}A$ prolong to a cross section $S^*$ of ${\xi}$ under either of the following hypothesis: (H1) The space F is (m-1)-connected for each $m{\leq}dim$ B. (H2) There is a relative CW-complex (Y, X) such that $B=Y{\times}I$ and $A=(X{\times}I)$ ${\cap}(Y{\times}O)$, where I=[0, 1]. (For proof see p.21 [2]).

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Absorption properties and size distribution of aerosol particles during the fall season at an urban site of Gwangju, Korea

  • Park, Seungshik;Yu, Geun-Hye
    • Environmental Engineering Research
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    • v.24 no.1
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    • pp.159-172
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    • 2019
  • To investigate the influence of pollution events on the chemical composition and formation processes of aerosol particles, 24-h integrated size-segregated particulate matter (PM) was collected during the fall season at an urban site of Gwangju, Korea and was used to determine the concentrations of mass, water-soluble organic carbon (WSOC) and ionic species. Furthermore, black carbon (BC) concentrations were observed with an aethalometer. The entire sampling period was classified into four periods, i.e., typical, pollution event I, pollution event II, and an Asian dust event. Stable meteorological conditions (e.g., low wind speed, high surface pressure, and high relative humidity) observed during the two pollution events led to accumulation of aerosol particles and increased formation of secondary organic and inorganic aerosol species, thus causing $PM_{2.5}$ increase. Furthermore, these stable conditions resulted in the predominant condensation or droplet mode size distributions of PM, WSOC, $NO_3{^-}$, and $SO{_4}^{2-}$. However, difference in the accumulation mode size distributions of secondary water-soluble species between pollution events I and II could be attributed to the difference in transport pathways of air masses from high-pollution regions and the formation processes for the secondary chemical species. The average absorption ${\AA}ngstr{\ddot{o}}m$ exponent ($AAE_{370-950}$) for 370-950 nm wavelengths > 1.0 indicates that the BC particles from traffic emissions were likely mixed with light absorbing brown carbon (BrC) from biomass burning (BB) emissions. It was found that light absorption by BrC in the near UV range was affected by both secondary organic aerosol and BB emissions. Overall, the pollution events observed during fall at the study site can be due to the synergy of unfavorable meteorological conditions, enhanced secondary formation, local emissions, and long-range transportation of air masses from upwind polluted areas.