• 제목/요약/키워드: conversion

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DSC를 활용한 상용전력변환 시스템에 관한 연구 (A study on the power conversion system using Dye-Sensitized Solar cell)

  • 김진영;박성준;박해명;김우성;김휘영;김희제
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.195-198
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    • 2006
  • The technology of Solar Power conversion System is defined as a solar cell that changes the sol ar energy into the direct electric energy, power conversion and control technology that convert the dc power into ac power The solar cell module, power conversion, and a control part in component parts consisting a solar power conversion system have influence on its performance. The roles of power conversion and a control part supply the direct current generated by solar cell module for a load with high efficiency as conveniently as possible in this study, the power conversion systen that can generate solar power using DSC module was developed and its characteristics was experimented. The characteristics of the DSC power conversion system including MOSFET and DSP micro processor, high speed devices, was simulated using Psim. According to the results, converter and inverter was manufactured in detail and the performance characteristics were studied.

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Estimating the Soil Volume Conversion Factor of Weathered Ground with Consideration of Field Situations

  • Jin, Kyu-Nam;Cho, Gye-Chun;Lee, Jung-Min;Ryu, Hee-Hwan;Park, Sung-Wook
    • 토지주택연구
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    • 제2권2호
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    • pp.145-155
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    • 2011
  • It is very important for successful construction to estimate the soil volume conversion factor of domestic weathered ground accurately and reasonably. However, it is very difficult to quantify the weathering degree of weathered ground at the field, so that the soil volume conversion factor used in Korea is often dependent upon the standard of foreign countries. Besides, the soil volume conversion factor of domestic weathered ground has been rarely studied and the use and accuracy of the soil volume conversion factor have been questioned persistingly. This study suggests a simple but robust method for estimating the soil volume conversion factor and measuring the weathering degree reasonably, and attempts to establish the utilization of a soil volume conversion factor measurement system based on experimental and analytical results. We made relationship between electrical resistivity and weathering degree presented from weathering index obtained through laboratory tests using field samples, and an estimation method of in-situ weathering degree for granites and a calculation method of soil volume conversion factor using electrical resistivity. And also, we suggested the photogrametry measurement-equipment system for measuring the volume of cargo box and the application plan of stand equipment and RFID for calculating the earth volume and distinguishing buggies in order to design the measurement system for soil volume conversion factor applicable to the field. Ultimately, the Weathered Earth-work Management Program (WEMP) was developed, so field managers may easily obtain the information about earth volume and soil volume conversion factor at the weathered ground.

Conversion of Gycosylphosphatidylinositol (GPI)-Anchored Alkaline Phosphatase by GPI-PLD

  • Moon, Young-Girl;Lee, Hyun-Jung;Kim, Mee-Ree;Myung, Pyung-Keun;Park, Soo-Young;Sok, Dai-Eun
    • Archives of Pharmacal Research
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    • 제22권3호
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    • pp.249-254
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    • 1999
  • Enzymatic conversion of brain glycosylphosphatidylinositol-linked alkaline phosphatase (GPI-AP), amphiphilic, was examined. When GPI-AP was incubated with glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD), a negligible conversion of GPI-AP to hydrophilic form was observed. The inclusion of monoacylglycerols enhanced the enzymatic conversion, although the action of monoacylglycerols differed greatly according to the size of acyl group; the enzymatic conversion was enhanced considerably in the presence of monoacylglycerols possessing acyl group of longer chain length ($C_{10-}C_{18}$), which monoacylglycerols with acyl moiety of shorter length ($C_{4-}C_{8}$) did fail to augment the enzymatic conversion. Noteworthy, monooleoylglycerol was much more effective than the other monoacylglycerols in promoting the enzymatic conversion, indicating a beneficial role of the unsaturation in acyl chain. Meanwhile, ionic amphiphiles such as monohexadecyllysophosphatidylcholoine and palmitoyl-carnitine decreased the enzymatic conversion of GPI-AP in a concentration-dependent manner, with monohexadecyllysophosphatidylcholine and palmitoyl-carnitine deceased the enzymatic conversion of GPI-AP in a concentration-dependent manner, with monohexadecyllysophosphatidylcholoine being more inhibitory than palmitoylcarnitine. Separately when GPI-AP was exposed to various oxidants prior to the incubation with GPI-PLD, a remarkable decrease of the enzymatic conversion was observed with hypochlorite and peroynitrite generators, but not $H_{2}O_{2}$. In further study, hypochlorite was found to inactivate GPI-PLD at low concentrations ($3~100{\mu}M$). From these results, it is suggested that the enzymatic conversion of GPI-AP by GPI-PLD may be regulated in vivo system.

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수도권에서 아황산가스의 황산염으로 전환시 각 과정의 상대적 기여도 (The Relative Contribution of SO2-to-sulfate Conversion Processes over the Metropolitan Seoul Area)

  • 배수야;김용표
    • 한국대기환경학회지
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    • 제19권4호
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    • pp.451-465
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    • 2003
  • The major conversion processes of SO$_2$ to sulfate are reactions in gaseous, aqueous phase and on dust surface. Using the measurement data in Ganghwa, the background area of metropolitan Seoul Area, the relative contiribution of the conversion processes are estimated. Generally, aqueous cloud if the most important conversion path followed by dust surface, gas, and aqueous aerosol. Importance of conversion on dust surface increases for the dust storm period. The total conversion rate values over the metropolitan Seoul area are between 1.5 and 8.8$\times$10$^{-11}$ mole m$^{-3}$ air.

전환장애(轉換障碍)에 의한 실성증(失聲症) 환자의 치험 1례 (A Clinical Report of a Patient with Conversion Aphonia)

  • 변석미;신상호;김미보;윤화정;고우신
    • 한방안이비인후피부과학회지
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    • 제21권2호
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    • pp.206-213
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    • 2008
  • Objective : Conversion disorder is a psychiatric condition in which people express emotional distress through physical signs and symptoms involuntarily. Aphonia is one of the frequent symptoms of conversion disorder. The premise of this study is that oriental medical treatments would alleviate the symptoms of a patient with aphonia caused by conversion disorder. Methods : In this study, the subject is a patient with conversion disorder who afflicted aphonia after her travel. The patient was treated in Ulsan Oriental Medical Hospital of Dong-Eui University. Herbal medicine, acupuncture, and other oriental treatments were diagnosed to her. Results : Oriental medical treatments have an effect on a patient experiencing aphonia caused by conversion disorder.

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학업과 관련된 전환장애 환자 치험 2례 (The Clinical Report about two Conversion Disorder Patient resulted from School Work)

  • 이동원;김은정
    • 동의신경정신과학회지
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    • 제12권2호
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    • pp.215-221
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    • 2001
  • Conversion disorder is disease that anxiety is converted to physical symptom by suppression of complication unconsciously. This case is that of conversion disorder resulted from school work. The treatment of Conversion disorder is anxiety syndrome's removement. But if not possible, as a symptomatic treatment, approvement of symptom is significant, in a sense. By use of Oriental medical treatment, we could improve symptoms of two case conversion disorders. Sooner or later, the patients gained a complete recovery. So, more objective study and treatment about conversion disorder by Oriental medicine's demonstration is needed.

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범용 DSP를 이용한 3 채널 디지탈 CVSD 전송율 변환기 개발 (Developement of a 3 channel digital CVSD bit-rate converter using a general purpose DSP)

  • 최용수;강홍구;김성윤;박영철;윤대희
    • 한국통신학회논문지
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    • 제22권2호
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    • pp.306-317
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    • 1997
  • This ppaer presents a bit-rate conversion system for efficient communications between 3 channel CVSD systems with different bit-rates. The proposed conversion system is implemented in the digital domain and specially, the conversion problem between 32 Kbps and 16 Kbps CVSD systems is studied. The conventional conversion system implemented in the analog domain allows signals to be easily degraded by external noises. To overcome this problem, a digital CVSD bit-rate conversion system robust to external noises is developed. the new systemdecodes CVSD bit sequences and converts sampling rates of decoded signals, then encodes signals at target bit-rates. Since linear phase property does not matter in this application, instead of FIR filters a IIR filter is employed to reduce the system complexity. Therefore, a 3 channel digital CVSD bit-rate conversion system was successfully real-time implemented using a general purpose DSP. In addition, conversion problems with unkown time constants were experimented and good experimental results were obtained.

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실리콘 박막 태양전지를 위한 CdSe계 양자점 광변환구조체

  • 신명훈
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.135.2-135.2
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    • 2014
  • Photon conversion technology for thin film solar cells is reviewed. The high-energy photons which are hardly absorbed in solar cells can be transformed the low energy photon by the photon conversion process such as down conversion or down shift, which can improve the solar cell efficiency over the material limit. CdSe-based quantum dot materials commonly used in LED can be used as the photon conversion layer for Si thin film solar cells. The photon conversion structure of CdSe-based quantum dot for Si thin film solar cells will be presented and the pros and cons for the Si thin film solar cells integrated with the photon conversion layers will be discussed.

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녹두(Vigna radiata)의 하배축에서 ACC의 에틸렌 전환에 미치는 $Ca^{2+}$의 효과 ($Ca^{2+}$ Effect on the Conversion of ACC to Ethylene in Mungvean(Vigna radiata) Hypocothls)

  • 서효원
    • Journal of Plant Biology
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    • 제36권3호
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    • pp.233-239
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    • 1993
  • Effect of Ca2+ on the conversion of 1-aminocycloprophane-1-carboxylic acid (ACC) to ethylene was studied with 2.5 day-old mung bean hypocotyl segments. The conversion of ACC in these tissues was inhibited by plasmolysis and sulfosuccinimidyl (hydroxyphenyl) propionate (sulfo-SHPP). The ACC induced ethylene production in HC (high calcium)-tissue grown on the Ca2+ added medium was greater than that in N (normal)-tissue. HC-tissue had a lower inhibition rate of ACC conversion by EGTA and Ca2+ -channel blockers than N-tissue. The rates of the ACC conversion by both kinds of tissues were stimulated by the Ca2+ ionophore A23187. From these results, we suggests a mechanism for the stimulative effect of Ca2+ on the conversion of ACC to ethylene as follows; in some tissues where ACC conversion is linked with plasma membrane, Ca2+ may be transported from apoplast through Ca2+ -channel into the cytoplasm ad stimulate ACC-oxidase activity.

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Ortho-para 수소변환이 수소액화성능에 미치는 영향 (Effects of ortho-para hydrogen conversion on hydrogen liquefaction performance)

  • 최항집;강병하;최영돈
    • 설비공학논문집
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    • 제12권2호
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    • pp.131-139
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    • 2000
  • A direct hydrogen liquefaction equipment has been developed and tested, which consists of a GM refrigerator, a liquefaction vessel, a radiation shield, a cryostat, and an ortho-para converter with catalyst. The effect of ortho-para hydrogen conversion on the performance of hydrogen liquefaction has been investigated. The time needed for the hydrogen liquefaction process with hydrogen pressure charge of 4 atm was delayed to around 75 minutes, and the liquefied mass flow rate of the hydrogen was about 0.0150∼ 0.0205 g/s when the hydrogen was liquefied with the direct hydrogen liquefaction system considering ortho-para conversion. With ortho-para conversion, the liquefied mass flow rate decreased up to 20%. Considering ortho-para conversion, there were up to 30% increase in the work input per unit liquefied mass flow rate. When the ortho-para conversion was considered, FOM decreased to be about 0.031∼0.045.

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