• Title/Summary/Keyword: DVM

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A Design and Implementation of Sample Distributed Virtual Machine for Distributed Environment (분산환경을 위한 Sample Distributed Virtual Machine 설계 및 구현)

  • Yang, Il-Deung;Lee, Seok-Hee;Kim, Soeng-Ryeol
    • The KIPS Transactions:PartA
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    • v.11A no.4
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    • pp.251-256
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    • 2004
  • By large quantity supply of high efficiency computers, various kind of distributed resource has been extravagant around. Use this distributed resource, if exclude concept of systems by each field, module, operation and administration then we can use it into minimum expense. Hereupon, accommodate some among contents that is proposed through 'Proposal of DVM and DESPL that have apply in distributed environment' and designs and implements SDVM. The user who use SDVM can use into minimum expense without concept of distributed environment.

Traceable AC Voltage and Current Measurements Using Digital Sampling Technique (디지털 샘플링 방법을 사용한 교류전압과 전류의)

  • Wijesinghe, W.M.S.;Park, Young-Tae
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.686_687
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    • 2009
  • The traceability maintenance system for the AC voltage and current has been developed at the frequency range of 20 Hz to 100 Hz without using any compensation technique which is used at thermal converter (TC) ac-dc transfer system at low frequencies. The system uses a digital voltmeter (DVM) as a data acquisition system of the input waveform and stored data in memory. The developed algorithm acquires and processes the sampling data to calculate the root mean square (rms) value of the input voltage of DVM which operates at DC 10 V range for better accuracy. The best uncertainty of the AC voltage measurements is $3 {\mu}V/V$ within the frequency range. The best uncertainty of the AC current measurements is better than the $5 {\mu}A/A$ and mainly depend on the current to voltage converter, ac-dc current shunt or Current Transformer (CT), used for the measurement

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A Comparitive Study of MAUT and AHP in Priority Setting of R&B Projects (연구개발사업 우선순위 설정에 있어서 다속성효용이론(MAUT)과 계층분석과정(AHP)의 비교)

  • 박주형;김정흠
    • Journal of Korea Technology Innovation Society
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    • v.2 no.2
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    • pp.201-218
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    • 1999
  • The article contains an introduction of possibility of applying Multi-Attribute Utility Theory(MAUT) for priority setting of R&D projects. MAUT is compared with AHP, which is widely used recently. These two techuiques are applied to set priorities of R&D projects In a Government-funded Research Institute. Six criteria are chosen from consultation with decision makers. They are composed of 1) validity as representative projects, 2) possibility of resource mobilization, 3) spillover effect of developed technologies, 4) possibility of success, 5) scope of participation and 6) clarity of research goal. To set priorities of R&D projects, SMART(Simple MultiAttribute Rating Technique) and DVM(Difference Value Measurement) out of many MAUT methods are used to design the utility function and to determine the weights among criteria. The aggregation model is additive on the assumption the criteria are independent. AHP executes pairwise comparisons for criteria and alternatives. From the results of the case study, the results and theoretical characteristics are compared.

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Offloading Framework for Legacy Application in Mobile Cloud Environments (모바일 클라우드 환경에서 레거시 어플리케이션을 위한 오프로딩 프레임워크)

  • Kim, Soon-Gohn;Yousafzai, Abdullah;Ko, Kwang-Man
    • Proceedings of the Korea Information Processing Society Conference
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    • 2016.10a
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    • pp.179-180
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    • 2016
  • 최근까지 모바일 디바이스와 고성능 클라우드 서버는 동일한 DVM 실행시간 환경에서 오프로딩을 통해 모바일 디바이스의 어플리케이션에 대해 실행속도 개선하려는 연구가 진행되고 있다. 본 논문에서는 안드로이드 실행시간 환경이 네이티브 어플리케이션을 지원하는 ART로 완전하게 전환되는 상황에서 DVM에서 실행되고 있는 모바일 레거시 어플리케이션에 대해 모바일 디바이스의 복잡한 계산 부담을 줄여 실행속도를 향상시고, 이를 통해 배터리 소모를 감소시키는 프로세스 단위 오프로딩 프레임워크에 대한 설계 내용을 제시한다.

Vertical Migration and Horizontal Distribution of Chaoborus Larvae in Lake Fukami- ike, Japan

  • Nagano, Mariko;Tanaka, Masaaki;Yagi, Akihiko
    • Korean Journal of Ecology and Environment
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    • v.38 no.spc
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    • pp.27-30
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    • 2005
  • Diel vertical migration (DVM) and horizontal distribution of Chaoborus flavicans larvae were studied in Lake Fukami-ike (maximum depth 7.75 m, Central Japan). The larvae showed a clear migration in the 4 ${\sim}$ 7 m layer during the day and throughout the water column at night. It should be noted that, while old instar distributed throughout the column during the night. Young instar was found only in the 1 ${\sim}$ 4 m layer. An examination of horizontal distribution revealed that larval stage was clearly related with the depth. It suggests that Chaoborus appear to exist in the deeper area during the larval stage.

An Application of the Acoustic Similarity Law to Centrifugal Fan Noise by Numerical Calculation (수치기법을 이용한 원심홴 소음의 음향학적 상사법칙 적용)

  • 전완호;이덕주
    • Journal of KSNVE
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    • v.9 no.5
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    • pp.955-965
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    • 1999
  • Centrifugal fans are widely used and the noise generated by the these machines causes one of the most serious problems. In general, the centrifugal fan noise is often dominated by tones at BPF(blade passage frequency) and its higher harmonics. This is a consequence of the strong interaction between the flow discharged form the impeller and the cutoff in the casing. However, only a few researches have been carried out on predicting the noise because of the difficulty in obtaining detailed information about the flow field and casing effects on noise radiation. The objective of this study is to understand the generation mechanism of sound and to develop a prediction method for the unsteady flow field and the acoustic pressure field of a centrifugal fan. We assume that the impeller rotates with a constant angular velocity and the flow field of the impeller is incompressible and inviscid. So, a discrete vortex method (DVM) is used to model the centrifugal by the unsteady Bernoulli equation. Lowson's method is used to predict the acoustic source. A centrifugal impeller and wedge introduced by Weidemann are used in the numerical calculation and the results are compared with the experimental data. Reasonable results are obtained not only for the peak frequencies but also for the amplitudes of the tonal sound.

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