• Title/Summary/Keyword: a conversion factor

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Energy Conversion in the Rossby Adjustment Process for Step-Like Initial Disturbances (初期攪亂에 의한 로스비 形過程에 있어서의 에너지 換)

  • 성영호
    • 한국해양학회지
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    • v.21 no.3
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    • pp.131-135
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    • 1986
  • Conversion of energy from potential to kinetic form is considered when a step-like initial disturbance is released to reach a final steady state. For small amplitute disturbances, linearization can be made and it is proved analytically that the conversion factor (ratio of generated kinetic to loss in potential energies) asymptotically approaches to 1/3 as the horizontal scale of disturbances becomes large.

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A Study on The Conversion Factor between Heterogeneous DBMS for Cloud Migration

  • Joonyoung Ahn;Kijung Ryu;Changik Oh;Taekryong Han;Heewon Kim;Dongho Kim
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.8
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    • pp.2450-2463
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    • 2024
  • Many legacy information systems are currently being clouded. This is due to the advantage of being able to respond flexibly to the changes in user needs and system environment while reducing the initial investment cost of IT infrastructure such as servers and storage. The infrastructure of the information system migrated to the cloud is being integrated through the API connections, while being subdivided by using MSA (Micro Service Architecture) internally. DBMS (Database Management System) is also becoming larger after cloud migration. Scale calculation in most layers of the application architecture can be measured and calculated from auto-scaling perspective, but the method of hardware scale calculation for DBMS has not been established as standardized methodology. If there is an error in hardware scale calculation of DBMS, problems such as poor performance of the information system or excessive auto-scaling may occur. In addition, evaluating hardware size is more crucial because it also affects the financial cost of the migration. CPU is the factor that has the greatest influence on hardware scale calculation of DBMS. Therefore, this paper aims to calculate the conversion factor for CPU scale calculation that will facilitate the cloud migration between heterogeneous DBMS. In order to do that, we utilize the concept and definition of hardware capacity planning and scale calculation in the on-premise information system. The methods to calculate the conversion factor using TPC-H tests are proposed and verified. In the future, further research and testing should be conducted on the size of the segmented CPU and more heterogeneous DBMS to demonstrate the effectiveness of the proposed test model.

Balanced Forward-Flyback Converter for High Efficiency and High Power Factor LED Driver (고효율 및 고역률 LED 구동회로 위한 Balanced Forward-Flyback 컨버터)

  • Hwang, Min-Ha;Kang, Jeong-Il;Han, Sang-Kyoo
    • The Transactions of the Korean Institute of Power Electronics
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    • v.18 no.5
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    • pp.492-500
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    • 2013
  • A balanced forward-flyback converter for high efficiency and high power factor using a foward and flyback converter topologies is proposed in this paper. The conventional AC/DC flyback converter can achieve a good power factor but it has the high offset current through the transformer magnetizing inductor, which results in a large core loss and low power conversion efficiency. And, the conventional forward converter can achieve the good power conversion efficiency with the aid of the low core loss but the input current dead zone near zero cross AC input voltage deteriorates the power factor. On the other hand, since the proposed converter can operate as the forward and flyback converters during switch turn-on and turn-off periods, respectively, it cannot only perform the power transfer during an entire switching period but also achieve the high power factor due to the flyback operation. Moreover, since the current balanced capacitor can minimize the offset current through the transformer magnetizing inductor regardless of the AC input voltage, the core loss and volume of the transformer can be minimized. Therefore, the proposed converter features a high efficiency and high power factor. To confirm the validity of the proposed converter, theoretical analysis and experimental results from a prototype of 24W LED driver are presented.

Organic Photovoltaic Devices on $HNO_3$-Treated Multilayer Graphene Electrodes

  • Jung, Yong Un;Na, Seok-In;Kim, Han-Ki;Kang, Seong Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.235-235
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    • 2013
  • We reported on the characteristics of organic solar cells (OSCs) fabricated on $HNO_3$-treated multilayer graphene (MLG) transparent electrodes. MLG electrodes were prepared using a chemical vapor deposition and a multi-transfer process. Compared to organic solar cells (OSCs) on the ITO electrodes had a fill factor of 65.97%, and a power conversion efficiency (PCE) of 3.364%, OSCs on the MLG (three-layer graphene) electrodes with sheet resistance of $274{\pm}1{\Omega}$/square and transparency of 92.1% had a fill factor of 43.46%, and a power conversion efficiency (PCE) of 2.019%. However, OSCs on the HNO3-treated MLG electrodes with lower sheet resistance of $119{\pm}1{\Omega}$/square had a fill factor of 57.54%, and a PCE of 2.861%. The results would provide a promising method to improve the performance of large-area OSCs based on MLG electrodes.

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Method of Estimating Environment Conversion Factor Analyzing Environment Factors of MIL-HDBK-217F (MIL-HDBK-217F의 환경인자 분석을 통한 환경변환계수 추정)

  • Jeong, Da-Un;Yun, Hui-Sung;Lee, Eun-Hak;Kwon, Dong-Soo;Lee, Seung-Hun
    • Journal of Applied Reliability
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    • v.11 no.2
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    • pp.141-149
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    • 2011
  • Environment Conversion Factors, which are stipulated in System Reliability Toolkit, have a lot of advantages once applied in a reliability data handbook such as NPRD-95, during the process of reliability prediction. However, the factors have a restriction in their applications because they don't deal with a few environments, e.g., Missile Launch (ML). In this study, environment factors of various components from MIL-HDBK-217F were analyzed to address this problem. Statistical computations showed that converting from Airborne Rotary Wing (ARW) to Missile Launch (ML) was the most coherent by comparing coefficient of determination. In addition, conversion factors from System Reliability Toolkit and those from the statistical calculations were evaluated in terms of their similarities.

A Classification of Conversion Factors of Relative Values in the National Health Insurance (건강보험 환산지수의 유형별 분류방안)

  • Kim, Jin-Hyun;Choi, Byung-Ho
    • Journal of Society of Preventive Korean Medicine
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    • v.10 no.2
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    • pp.147-158
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    • 2006
  • The purpose of this paper is to review the empirical study results of conversion factors(unit prices) for relative values of health care services in the national health insurance system and establish optimal classification of health care institutions for feasible contract of conversion factors between National Health Insurance Corporation(NHIC) and provider groups, based on legal backgrounds and types of health care service delivery system. some empirical research evidences shows the validity of applying multiple conversion factors to annual contract for reimbursement in the national health insurance. Policy recommendations suggest that clinic, hospital, general hospital, tertiary hospital, dental clinic, oriental medical clinic, pharmacy, and public health centers would be a basic category of provider groups for a meaningful price contract between the NHIC and providers.

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Experimental Study on the Relationships between Earthwork Volumes and Soil Conversion Factor with Depth (심도별 토량환산계수와 토공량 변화에 관한 실험적 연구)

  • Gichun Kang;Kyoungchul Shin;Seong-kyu Yun
    • Land and Housing Review
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    • v.14 no.3
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    • pp.137-144
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    • 2023
  • The amount of soil cutting, transported, and filing up the soil in the project area is considered to change the volume depending on the condition of the soil; the volume change rate of the soil is calculated by collecting undisturbed samples below 1 m to 2.0 m above the surface through test pits. In this study, large-scale field tests are carried out. There are areas with an excavation depth of 10m or more, but some errors have occurred in calculating the soil volume by uniformly applying the soil conversion factor for a depth of 1 to 2 m. According to the field tests, the earthwork volumes applied with the soil conversion factor for each depth increase by 3.9 to 9.4% compared to the soil volume applied uniformly with that of 2 m depth.

Analysis of Impedance Performance for Condenser by Harmonic Current Source (고조파 전류원에 의한 콘덴서 임피던스 특성 해석)

  • Kim, Jong-Gyeum;Park, Young-Jeen
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.4
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    • pp.57-64
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    • 2011
  • Most of the user has been used linear load and non-linear load. The former is usually inductive load which is needed power factor compensation, the latter is power conversion system device. Actually two kinds of load is used together in the customer application. Generally capacitor is used for power-factor compensation of inductive load and reduction harmonics of non linear load with reactor. Non-linear load generates harmonic current for its energy conversion process. If harmonic current pass along the low impedance side of distribution system, the magnification of voltage and current is appeared by the series and parallel resonance. As a result, condenser has received a bitter electrical stress by the harmonic component. In this paper, we analyzed that how resonance is changed by the 5-th harmonic current pattern and proposed an alternative plan for non-magnification.

Rock/Soil proportion estimation using image processing technique (광학식 측정방법을 활용한 풍화지반 버럭의 암/토사 구성비율 추정방법)

  • Jin, Kyu-Nam;Jin, Kim-Young;Park, Sung-Wook;Cho, Gye-Choon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.1425-1432
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    • 2010
  • In large construction site, although soil conversion factor is so significant to preliminary design, operation design and calculating the cost of construction that it is important to take reasonable estimation and application, the standard of soil conversion factor for weathered ground doesn't clearly suggested yet. So in this study, at first we obtain the image using DSLR - high resolution camera and Laser scanner in the Haeng-Bok city constructin site, then analysis the ratio of soil and rock using various image processing method(Sobel method, Laplace method, Highpass filter, Hue and Saturation analysis). Mutual comparation with the result of image processing analysis and manual segmentation of 5case image in the cad. As a result, best image processing method was different for each case. In case of high propotion of rock, Laplace was best and in case of high propotion of soil, Highpass was best, and mixed case Laplace was best.

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The Conversion factor for Allocation of Interconnection Charge Between Fixed and Mobile Networks (유무선망 상호접속료 배부를 위한 서비스간 환산계수 연구)

  • Kim, Jae-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.7
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    • pp.3275-3279
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    • 2011
  • The matter of the calculation of the mutual access fee has become one of the hottest issues among service providers and attracted concerns from concerned regulatory authorities. It is essential to conclude a rational and systematic procedure for interconnection costs and charge between fixed and mobile networks. In this paper, I proposed the conversion factor scheme between circuit switched voice and packet switched data service in the domestic CDMA mobile system based on analysis of the rational GSM allocation method of common cost.