• 제목/요약/키워드: energy level

검색결과 6,742건 처리시간 0.044초

전자레인지 가열시 분쇄 돈육 패티의 지방함량과 가열특성과의 상관관계에 관한 연구 (The Relationship between Fat Level and Quality Properties of Ground Pork Patties Cooked by Microwave Energy)

  • 최지훈;정종연;최윤상;이의수;김천제
    • 한국축산식품학회지
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    • 제28권3호
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    • pp.295-300
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    • 2008
  • This study was carried out to elucidate the relationship between different fat levels (0%, 5%, 10%, 15%, 20%, and 25%) and the quality of ground pork patties cooked to reach an internal temperature of $75^{\circ}C$ in a microwave oven. The relationship between fat level and cooking rate of pork patties cooked by microwave energy was highly significant ($R^2=0.72$), and had a low determination coefficient ($R^2=0.55$). The relationship between fat level and total cooking loss of pork patties cooked by microwave energy was also very significant, with a high correlation coefficient of $R^2=0.89$. The correlation coefficient between fat level and cooking drip loss of patties cooked by microwave energy was 0.92, which was highly significant. Although the correlation coefficient between fat level and evaporation loss had a negative value ($R^2=-0.63$), there was a highly significant relationship between fat level and shear force of pork patties cooked by microwave energy.

Coordination between Voltage-Limiting Surge Protective Devices in Surge Currents Caused by Direct Lightning Flashes

  • Shin, Hee-Kyung;Lee, Jae-Suk
    • 조명전기설비학회논문지
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    • 제29권4호
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    • pp.116-125
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    • 2015
  • This paper presents experimental results obtained from actual installation conditions of surge protective devices (SPDs), with the aim of understanding the coordination of cascaded Class I and Class II SPDs. This paper also proposes effective methods for selecting and installing coordinating cascaded SPDs. The residual voltage of each SPD and the energy sharing of an upstream Class I tested SPD and a downstream Class II tested SPD were measured using a $10/350{\mu}s$ current wave. In coordinating a cascaded voltage-limiting SPD system, it was found that energy coordination can be achieved as long as the downstream SPD is a metal oxide varistor with a higher maximum continuous operating voltage than the upstream SPD; however, it is not the optimal condition for the voltage protection level. If the varistor voltage of the downstream SPD is equal to or lower than that of the upstream SPD, the precise voltage protection level is obtained. However, this may cause serious problems with regard to energy sharing. The coordination for energy sharing and voltage protection level is fairly achieved when the cascaded SPD system consists of two voltage-limiting SPDs separated by 3 m and with the same varistor voltage.

항암화학요법을 받는 암환자의 에너지섭취량과 피로 (Energy Intake and Fatigue in Patients Receiving Chemotherapy)

  • 변미숙;김나현
    • Journal of Korean Biological Nursing Science
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    • 제14권4호
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    • pp.258-267
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    • 2012
  • Purpose: The purpose of this study was to identify the relationship between energy intake and fatigue in cancer patients receiving chemotherapy. Methods: A total of 106 subjects had participated in this study. Data were collected at a university hospital in D city from September 1st to November 10th, 2010. Energy intake including carbohydrates, protein and fat was measured by scale and analyzed using Can Pro 3.0 program. Fatigue level was measured by the Revised Piper Fatigue Scale. Data were analyzed using descriptive analysis, t-test, ANOVA and Pearson correlation coefficient with SPSS/WIN 15.0. Results: The mean calorie intake during chemotherapy was $906.53{\pm}201.28Kcal/day$ which was 45.3% of the recommended daily calorie intake. The mean of protein intake level was $43.62{\pm}11.13g/day$, and it was low compared to the recommended daily protein intake. Calories, carbohydrates, and protein levels on 3rd day after chemotherapy were significantly lower than those of 2nd day after chemotherapy (p<.001). The fatigue level during chemotherapy was $5.77{\pm}0.77$ which was moderate level of fatigue. There was a significant negative interrelation between energy intake and fatigue. Conclusion: Theses results suggested that nursing approaches to encourage dietary intake may be helpful to reduce fatigue for cancer patients receiving chemotherapy.

Five-level Inverter for Excitation Control of SRM Drive

  • Oh, Seok-Gyu;Park, Sung-Jun;Ahn, Jin-Woo
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제11B권3호
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    • pp.64-69
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    • 2001
  • Energy recovery in the regenerative region is very important when SRM is used in traction drive, This is to reduce en-ergy loss during mechanical braking and/or to have a high efficiency drive during braking To control excitation voltage in motor operation and regenerative voltage in the generator operation in the SRM multi-level voltage control is effective The paper sug-gests multi-level inverter which is useful for motoring and regenerative operation in SRM

스크류 열펌프 시스템의 운전제어 방안에 관한 연구 (A Study on the Operating Control of a Heat Pump System with Screw Compressors)

  • 박준택;이영수;김지영;채규정;양희정
    • 설비공학논문집
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    • 제25권3호
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    • pp.168-172
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    • 2013
  • A preliminary performance test of a 30RT 2-stage screw heat pump was carried out in order to develop a high performance large-scale unutilized energy source heat pump system, which will be used for district heating and cooling. In this study, two issues of the system operating control were investigated. The first issue is the mode switching control from 1-stage to 2-stage. A stable 2-stage heating operation is guaranteed, only if the load-side water inlet temperature is over a certain value, where the 1-stage heating operation should be done first from a cold start. The second issue is oil level control. An oil shortage problem in the low stage compressor, which depends on the degree of suction superheat, was solved by a proper oil level control scheme.

2단 종속 SPD시스템의 보호특성 (Protection Characteristics of Two-Stage Cascade SPD Systems)

  • 이복희;신희경
    • 조명전기설비학회논문지
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    • 제27권5호
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    • pp.95-103
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    • 2013
  • Protection of the electrical and electronic equipment against surges in low voltage AC power distribution systems is based on wide applications of surge protective devices(SPDs). Cascade application of SPDs located at the service entrance of a building and near sensitive equipment is intended to ensure the optimal voltage protection level and energy sharing among cascade SPDs. In this paper, when surges impinge at the service entrance of the building of interest, the protection characteristics of two-stage cascade SPD systems were investigated. The influence of the distance between the upstream and downstream SPDs on the voltage protection level and energy sharing of the two-stage cascade SPD systems were analyzed experimentally. It was found that the energy sharing of two-stage cascade SPD systems strongly depends on the distance between the two SPDs and the component of SPD. As the distance between the two SPDs increases, the energy absorbed by the upstream SPD increases while the energy absorbed by the downstream SPD decreases. Consequently, it is desirable to select the upstream and downstream SPDs having the proper energy capability with due consideration of the distance between the two SPDs.

에너지회생스너버를 적용한 하이브리드 3레벨 DC/DC 컨버터 (Hybrid Three-Level DC/DC Converter using an Energy Recovery Snubber)

  • 허예창;주종성;말론;김은수;강철하;이승민
    • 전력전자학회논문지
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    • 제22권1호
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    • pp.36-43
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    • 2017
  • This paper describes a hybrid multi-output three-level DC/DC converter suitable for a wide, high-input voltage range of an auxiliary power supply for a high-power photovoltaic generating system. In a high-power photovoltaic generating system, the solar panel output voltage depends on solar radiation quantity and varies from 450Vdc to 1100Vdc. The proposed hybrid multi-output three-level DC/DC converter, which is an auxiliary power supply, would be used as power source for control printed circuit boards and relay and cooling fans in a high-power photovoltaic generating system. The proposed multi-output ($24V_{DC}/30A$, $230V_{DC}/5A$) hybrid three-level boost converter, which uses an energy recovery snubber, is controlled by variable-frequency and phase-shifted modulations and can achieve zero-voltage switching with all operating conditions of input voltage and load range. Experimental results of a 2kW prototype are evaluated and implemented to verify the performance of the proposed converter.

Cyclic testing of innovative two-level control system: Knee brace & vertical link in series in chevron braced steel frames

  • Rousta, Ali Mohammad;Zahrai, Seyed Mehdi
    • Structural Engineering and Mechanics
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    • 제64권3호
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    • pp.301-310
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    • 2017
  • For further development of passive control systems to dissipate larger seismic energy and prevent the structures from earthquake losses, this paper proposes an innovative two-level control system to improve behavior of chevron braced steel frames. Combining two Knee Braces, KB, and a Vertical Link Beam, VLB, in a chevron braced frame, this system can reliably sustain main shock and aftershocks in steel structures. The performance of this two-level system is examined through a finite element analysis and quasi-static cyclic loading test. The cyclic performances of VLB and KBs alone in chevron braced frames are compared with that of the presented two-level control system. The results show appropriate performance of the proposed system in terms of ductility and energy dissipation in two different excitation levels. The maximum load capacity of the presented system is about 30% and 17% higher than those of the chevron braced frames with KB and VLB alone, respectively. In addition, the maximum energy dissipation of the proposed system is about 78% and 150% higher than those of chevron braced frames with VLB and KB respectively under two separate levels of lateral forces caused by different probable seismic excitations. Finally, high performance under different earthquake levels with competitive cost and quick installation work for the control system can be found as main advantages of the presented system.

에너지절약투자의 온실가스 배출 감소 효과 (The Effect of Energy-Saving Investment on Reduction of Greenhouse Gas Emissions)

  • 김현;정경수
    • 자원ㆍ환경경제연구
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    • 제9권5호
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    • pp.925-945
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    • 2000
  • This paper analyses the impact of energy-saving investment on Greenhouse gas emissions using a model of energy demand in Korea. SUR method was employed to estimate the demand equation. The econometric estimates provide information about the energy price divisia index, sector income, and energy saving-investment elasticities of energy demand. Except for energy price divisia, the elasticities of each variable are statistically significant. Also, the price and substitution elasticities of each energy price are similar to the results reported by the previous studies. The energy-saving investment is statistically significant and elasticities of each sector is inelastic. Using the coefficient of energy-saving investment and carbon transmission coefficient, the amount of reduction of energy demand and the reduction of carbon emissions can be estimated. The simulation is performed with the scenario that the energy-saving investment increase by 10~50%, keeping up with Equipment Investment Plan of 30% increase in energy-saving investment by 2000. The results show that the reduction of energy demand measured as 11.2% based upon 1995's level of the energy demand, in industrial sector. Accordingly, the carbon emissions will be reduced by 11.3% based upon 1995's level of the carbon emissions in industrial sector.

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