• Title/Summary/Keyword: Energy loss reduction

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Control of Rumen Microbial Fermentation for Mitigating Methane Emissions from the Rumen

  • Mitsumori, Makoto;Sun, Weibin
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.1
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    • pp.144-154
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    • 2008
  • The rumen microbial ecosystem produces methane as a result of anaerobic fermentation. Methanogenesis in the rumen is thought to represent a 2-12% loss of energy intake and is estimated to be about 15% of total atmospheric methane emissions. While methanogenesis in the rumen is conducted by methanogens, PCR-based techniques have recently detected many uncultured methanogens which have a broader phylogenetic range than cultured strains isolated from the rumen. Strategies for reduction of methane emissions from the rumen have been proposed. These include 1) control of components in feed, 2) application of feed additives and 3) biological control of rumen fermentation. In any case, although it could be possible that repression of hydrogen-producing reactions leads to abatement of methane production, repression of hydrogen-producing reactions means repression of the activity of rumen fermentation and leads to restrained digestibility of carbohydrates and suppression of microbial growth. Thus, in order to reduce the flow of hydrogen into methane production, hydrogen should be diverted into propionate production via lactate or fumarate.

A new high efficiency splitted sustaining driver for plasma display panel (PDP) (새로운 고효율 플라즈마 디스플레이 패널 분할 서스테인 구동 드라이버)

  • Yi Kang-Hyun;Choi Seong-Wook;Moon Gun-Woo;Park Jung-Pil;Jung Nam-Sung
    • Proceedings of the KIPE Conference
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    • 2006.06a
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    • pp.91-93
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    • 2006
  • A new High Efficiency splitted sustaining driver for Plasma Display Panel (PDP) is proposed. The proposed circuit is suitable for the large screen PDP. The features of the proposed circuit are zen voltage switching (ZVS) of all main power switches, the reduction of reaction power loss for energy recovering, the stable light emission and simple structure.

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The Power of "Mass Law"

  • 김정태;김정수;김운경;김석현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.710-714
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    • 2002
  • Whenever a noise problem of a product is concerned, a first step is to identify the energy transmission path whether it is an air-borne or a structure-borne. Depending on the characteristic of the noise path, tools on the noise reduction are different. In this paper. an important aspect of the “mass law” in a noise transmission has been investigated. Since an air-borne has 20 dB/Decade, and a structure-borne 10 dB/Decade of a sound transmission loss due to a mass, an engineer who aims to have a light product design should have an enough knowledge on the mass law, especially, the sensitivity of the weight itself. A honeycomb plate is examined as a sample of a light structure to implement a mass law.

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The Effect of Ginseng Saponin on Morphine Action of $Qo_2$ and Na, K content in Cerebral Cortex Slices of Rat (인삼(人蔘) Saponin 이 Morphine 에 의(依)한 Rat 대뇌피질절편(大腦皮質切片) 산소소비양(酸素消費量) 및 $Na^+$, $K^+$ 소장(消長)에 미치는 영향(影響))

  • Park, Chan-Woong
    • The Korean Journal of Pharmacology
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    • v.5 no.1
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    • pp.29-33
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    • 1969
  • The effects of Ginseng saponin on respiration and $Na^+$, $K^+$ content of rat cerebral cortex slices were investigated to determine the action of Ginseng saponin on brain cortex at cellular level. There are many reports for the study of Ginseng on central stimulatory action in experimental animals. The electrical stimulation of slices of cortex causes a loss of potassium. And the respiration is needed to maintain a supply of energy for active cation transport. The reduction in $Qo_2$ is a consequence of primary cessation of active cation transport. Ginseng saponin stimulated respiration which was depressed by Morphine. But there was no significant change of electrolyte. It is suggested that the Ginseng saponin act rather on metabolic process than neural excitatory mechanism in vitro.

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Analysis and Performance Test of Hybrid Transformer used in the Grid-Connected Photovoltaic Generation System (태양광 계통연계형 하이브리드 변압기의 해석 및 성능시험)

  • Kim, Ji-Ho;Park, Hoon-Yang;Shon, Jin-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.4
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    • pp.333-338
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    • 2014
  • This paper concerns the development of the transformer that can reduce harmonics supplied to the system if the output of photovoltaic inverter in the photovoltaic system is grid-connected, and suggests that problems of harmonics and power factor degradation in the grid-connected photovoltaic system can be improved. In this study, the burden of increasing the investment in new facilities and securing their installation space due to harmonics has been substantially eased through the development of a hybrid transformer possessing unbalanced function and harmonics reduction function using zig-zag coils, and most of all, it is expected that the development of such high efficiency hybrid transformer possessing functions of transformation and reducing harmonics can improve the power quality as well as prevent damages caused by harmonics, leading to suppress unnecessary loss of electric power and thereby contribute to energy savings.

A Method for $\frac{dv}{dt}$ suppression during switching of inverter (인버터 스위칭시 $\frac{dv}{dt}$ 억제 방법)

  • Suh, Duk-Bae;Sul, Seung-Ki
    • Proceedings of the KIEE Conference
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    • 1994.11a
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    • pp.156-158
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    • 1994
  • In recent days, the various adjustable speed drives are widely employed at the industrial applications for the purpose of energy saving and speed control. In particular, for the machine control applications. the switching frequency is required to be increased for better dynamic performance of the drive. Moreover, this also leads to the reduction of the switching loss of the device. For IGBT (Insulated Gate Bipolar Transistor), the most widely used switching device in the inverters below the 100[kW] range, the falling and falling time is of the order about $200{\sim}300[ns]$. Therefore unexpected phenomena occurs such as voltage spikes due to high gradient of current at the switching instant, the weakening of motor insulation due to high gradient of voltage. In this paper, a new voltage gradient suppression technique is presented in both theoretically and experimentally.

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A Study on Grid-connected Photovoltaic Current-Source Inverter using Parallel Connection (병렬연결을 이용한 계통연계형 태양광 전류형 인버터에 관한 연구)

  • Lim, Joung-Min;Cheang, Eui-Heang;Moon, Chae-Joo;Chang, Young-Hak;Kim, Eui-Sun
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1222-1223
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    • 2007
  • This paper suggests a 6-pulse-shift converter with PWM current-source inverter based on buck-boost configuration to improve the efficiency and to reduce the switching frequency of inverter for photovoltaic generation system, the device can be operated as interface system between solar module system and power system grid without energy storage cell. the circuit has six current-source buck-boost converter which operate chopper part has one full bridge inverter which make a decision the polarity of AC output. Therefore, the proposed PWM power inverter has advantages such as the reduction of witching loss and realization of unity power factor operation. the theoretical backgrounds are discussed and the input-output characteristics for the implemented prototype inverter using TMS320F2812 are verified experimentally in this paper.

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Development of rotor profile design technology for improving the screw compressor performance (공기압축기 성능향상을 위한 로터 프로파일 설계기술 개발 연구)

  • Kim, Tae-Yoon;Lee, Jae-Young;Lee, Dong-Kyun;Kim, Youn-Jea
    • Proceedings of the KSR Conference
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    • 2009.05b
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    • pp.585-592
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    • 2009
  • The performance of screw compressor depends on lots of design parameters of rotor profile, such as length of seal line, wrap angle, blow hole, suction and discharge port size, number of rotor lobe, etc. The optimum rotor profile makes it possible to increase the compression efficiency with low energy consumption, and to minimize the loss of power. In this research, a new rotor profile design and performance analysis are done by computer simulation. It is expected that the volumetric efficiency is improved because the internal leakage is reduced due to the minimization of blow hole and clearance, and the stiffness of rotors is increased due to the reduction of length to diameter ratio. Also, the specific power consumption will be secured for use ranging from low to high operation speed.

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Update on Health-related Quality of Life in Colorectal Cancer Patients

  • Young-Seok Cho
    • Journal of Digestive Cancer Research
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    • v.3 no.2
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    • pp.70-75
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    • 2015
  • Along with the recent trend of improved survival in patients with colorectal cancer (CRC), health-related quality of life (HRQoL) has become a significant outcome measure and its improvement is an important goal. The most widely adopted CRC specific HRQoL questionnaires are the European Organization for Research and Treatment of Cancer Qualityof-Life Questionnaire (EORTC QLQ-CR38) and the Functional Assessment of Cancer Therapy (FACT-C). CRC survivors without serious comorbidity or recurrence experience only minor deficits of overall HRQoL when compared to the general population. However, disease recurrence, progression, and more specific limitations, including weight loss, reduction in energy, and psychosocial problems like psychological distress and depression, could result in lower HRQoL. To improve HRQoL, further research is required to develop appropriate health education regarding lifestyle changes and personalized intervention strategies for CRC survivors.

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Methods for Improving the Applicability of Wood Powder Spacers to Liner Board Manufacturing (산업용지 제조에서 목질계 스페이서의 적용성 개선방안)

  • Yoon, Do-Hyun;Sung, Yong Joo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.4
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    • pp.160-167
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    • 2015
  • The reduction of energy consumption in papermaking process has been considered as one of the major issue in the paper technology. The energy efficiency of paper mill becomes more significant for the mill which manufacture the board grade products such as linerboard with recycled paper such as OCC. The application of lignocellulose spacer to the board grade paper stock would be the feasible solution by increasing the paper bulk and the drying efficiency. The major defects originated from the application of the lignocellulose spacer could be the loss of strength properties. In this study, the ways for improving the strength properties of the spacer-added linerboard were suggested and evaluated. The effects of the addition of various types polyelectrolytes were tested and the different methods of polyelectrolytes were applied for finding the efficient way. The pretreatments of lignocellulose spacer with the polyelectrolytes during wood spacer hydration resulted in the higher strength properties than the typical application method such as the addition to the mixed stock. Multilayer treatments of the spacer with polyelectrolytes were also evaluated and leaded to the higher strength properties with the similar bulk improvement.