• 제목/요약/키워드: Coefficient of utilization

검색결과 304건 처리시간 0.022초

단상 유도전동기의 이용률 변동에 대한 최적효율 산정기법 (Method of Optimum Efficiency to Coefficient of Utilization for Single Phase Induction Motor)

  • 김양호;김영선
    • 전기학회논문지P
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    • 제55권4호
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    • pp.155-160
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    • 2006
  • In this paper, deduced suitable optimization to request output condition after taking closely characteristic data of single phase induction motor(SIM) which is the possibility becoming economic is coming to be demanded. Motor proper move connection data took advantage of result of existing data and iron loss and copper loss, mechanical loss took advantage of statistical data, and decide motor move laking advantage of saving data and secondary resistance and optimum purpose of method that is proposed through single phase induction motor and comparison performance evaluation having on the same output parameter. That decide material factor, electric power damage ratio, and coefficient of utilization for optimum function by method that search request output and optimum values of efficiency case by case and decided is proper that is saved after take magnetizing reactance relationship. This research result which it sees against a material expense with use coefficient of utilization which is included in loss expense decides the same plan variable back the place efficiency is useful and will be applied.

의료급여 1종 노인 수급권자의 입원이용 (Hospital Services Utilization in Type-I Medicaid Elderly Beneficiaries)

  • 임승주
    • 동서간호학연구지
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    • 제15권2호
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    • pp.63-70
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    • 2009
  • Purpose: The purpose of this study was to evaluate hospital service utilization by the types of hospitals in Type I Medicaid claims frequently cited by elderly beneficiaries. Methods: Three frequently claimed inpatient diseases were selected: cerebral infarction, hypertension and diabetes mellitus. Relevant data were collected for the year 2008 from the computer database of the National Health Insurance Corporation. The data was analyzed using SPSS by descriptive statistics, ANOVA and coefficient of variation. Results: The coefficient of variance of hospitalization per episode was higher than daily hospital expenditure among hospitals for all three diseases. The coefficient of variance of hospitalization per episode was highest for cerebral infarction. The coefficient of variation of hospital expenditure per hospital day was highest for hypertension. Conclusions: Evaluating of the volume and pattern of hospital service utilization and the appropriateness for hospital admission for Type-I Medicaid elderly beneficiaries is important for Medicaid-based case management.

공간 반사율 및 배광에 따른 이용률 변화에 관한 기초적 연구 (A Fundamental Study on the Changes of Coefficients of Utilization by Surface Reflectance and Photometry)

  • 김유신;박병철;정근영;최안섭
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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    • pp.101-106
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    • 2008
  • Zonal cavity method, which is a kind of the lumen method, is used the calculation of the average illuminance on the workplane in an interior. Important factors of the method are cavity ratio, coefficient of utilization, and light loss factor. A Coefficient of Utilization varies with a kind of luminaires and is affected by surface reflectance of space. For this, the data from Coefficient of Utilization computation were analyzed with the same lumens and different photometry. This paper analyzes the changes of Coefficients of Utilization on the photometry of luminaires and surface reflectance of space.

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컨테이너 터미널의 적정 안벽능력 분석에 적용되는 계수들에 대한 분석 (An analysis about the coefficient used to estimate the quay capacity at the container terminal)

  • 김창곤
    • 한국항만학회지
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    • 제14권3호
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    • pp.259-267
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    • 2000
  • This study aims to analyse the coefficient used to estimate the quay capacity per year at the container terminal. The capacity of the container terminal is composed of the capacity at the quay side and the other working conditions at the back of the quay side. But when we refer the capacity of the container terminal, generally we used capacity as that of the container terminal. To estimate the quay capacity independently of the working conditions at the back of quay side, we calculate the quay capacity as th product of working hours per year, productivity of container crane and relate other coefficients, such that berth utilization, crane utilization and efficiency. So that coefficients are properly defined to reflect the other working conditions. If we calculate the quay capacity by the product of working hours modified by the berth utilization and crane productivity modified by the crane utilization and efficiency, the meaning of that coefficients must be strictly defined. So there could be no confusion to apply that coefficients to calculate the quay capacity. In this study, we exclusively define the meaning of the berth utilization, crane utilization and efficiency according to the internal-meaning of thats in the function to calculate the quay capacity. And compare each coefficients by decomposing the working hours at the terminal.

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Research on void drift between rod bundle subchannels

  • Shasha Liu;Zaiyong Ma;Bo Pang;Rui Zhang;Luteng Zhang;Quanyao Ren;Liangming Pan
    • Nuclear Engineering and Technology
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    • 제56권8호
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    • pp.3330-3334
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    • 2024
  • Void drift between subchannels in a rod bundle is a crucial phenomenon affecting the calculation accuracy of thermal-hydraulic parameters in SMRs. It holds significant importance in enhancing the precision of safety analysis for SMRs. Existing research on experiment and model of void drift between rod bundle subchannels is relatively rare, and the accuracy of model calculations requires improvement. In this study, experiments on gas-liquid two-phase non-equilibrium flow were conducted to measure the redistribution of two-phase flow induced by void drift in a 1 × 2 rod bundle. The experiment results indicated that in bubby flow regime with void fraction less than 0.3, the void diffusion coefficient showed little variation with changes in void fraction. However, in slug flow and annular flow regimes with void fraction exceeding 0.3, the void diffusion coefficient significantly increased with an increase in void fraction. Furthermore, a new void drift model was developed and validated based on a subchannel code. The overall predicted uncertainty for the outlet void fraction in the rod bundle benchmark was less than 13%.

딥드로잉 공정에서 재료 이용률을 높이기 위한 연구 (A Study on Improving The Coefficient of Utilization of Material in Deep Drawing Process)

  • 이경원;반재삼;박영진;조규종
    • 한국정밀공학회지
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    • 제19권4호
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    • pp.179-186
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    • 2002
  • This paper is the study on improving the coefficient of utilization of material in deep drawing process. Cylindrical cup drawing process is widely used in sheet metal forming process. The blank shape is one of the important things in sheet metal forming process. It is produced for the bridge of blank in a blanking process. The coefficient of utilization of material is much effected by this bridge of blank. This study offered a new process method to reduce the loss of material. The new blank shape offered and manufactured by new process method is investigated by a finite element method and the experiment. Then the wrinkling, the punch load, the thickness distribution is observed. This result is different from the result of circular blank process. And it is got that the Max strain, the wrinkle and the height of the wrinkle are effected by the holding farce and the punch load. As a result. if the processing optimum condition is found, the loss of material will be reduced. It is necessary to research systematically about determining the optimum vague of process variables.

딥드로잉공정에서의 재료 수율 향상에 관한 연구 (A Study on Improving The Coefficient of Utilization of Material in Deep Drawing Process)

  • 하종호;강형선;백호현
    • Journal of Advanced Marine Engineering and Technology
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    • 제33권4호
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    • pp.509-516
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    • 2009
  • This paper is the study on improving the coefficient of utilization of material in deep drawing process. Cylindrical cup drawing process is widely used in sheet metal forming process. The blank shape is one of the important things in sheet metal forming process. It is produced for the bridge of blank in a blanking process. The coefficient of utilization of material is much effected by this bridge of blank. This study offered a new process method to reduce the loss of material. The new blank shape offered and manufactured by new process method is investigated by a finite element method and the experiment. Then the wrinkling, the punch load, the thickness distribution is observed. This result is different from the result of circular blank process. And it is got that the Max strain, the wrinkle and the height of the wrinkle are effected by the holding force and the punch load. As a result, if the processing optimum condition is found, the loss of material will be reduced. It is necessary to research systematically about determining the optimum value of process variables.

염기성 소화에 대한 활성탄의 영향 (Effects of Powdered Activated Carbon on Anaerobic Digestion)

  • 김승현
    • 한국농공학회지
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    • 제32권3호
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    • pp.102-115
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    • 1990
  • Importance of anaerobic digestion as an energy generating device has been increased as fuel shortage becomes serieous. Several modification methods on the conventional digesters including Powdered Activated Carbon (PAC) addition and two-phase digestion were studied to enhance the gas production. This study investigated the effects of PAC on anaerobic digestion of chicken manure in terms of gas production and sludge stabilization. As a first experiment, an optimum PAC dose for efficient gas production was determined in a batch test. In semi-continuous experiments, an optimum Sludge Retention Time (SRT) at that PAC concentration and an overall substate utilization rate coefficient were investigated. A portion of gas increased by PAC addition was estimated using a substrate utilization rate coefficient of microorganisms attached on PAC. This test was performed in batch experiments using acetic acid as a substrate. The digesters for all experiments were kept 35${\pm}$ 1˚C in a heated water bath. Mixing was performed manually once a day and the produced gas was collected for daily reading. The following conclusions were made for this study. 1. Cptimum PAC concentration was 5% total solids, where gas production rate was increased by 20 percents. 2. Optimum SRT was 7.5 days. 3. Substrate utilization rate coefficient of microorganisms attached on PAC was about twice as much as that of suspended ones.

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수평 배수재로서 순환골재와 쇄석의 활용 방안 (Utilization of Recycled Aggregates and Crushed Stone as Horizontal Drains in Soft Ground)

  • 이달원;임진혁
    • 한국농공학회논문집
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    • 제52권6호
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    • pp.111-123
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    • 2010
  • In this study, laboratory model test on utilization of recycled aggregates and crushed stone as horizontal drains to use alternative material of sand in soft ground is practiced. The coefficient of permeability of the recycled aggregates and crushed stone showed largely 1.2~5.1 times and 2.0~3.3 times greater than sand, respectively. The horizontal coefficient of permeability in case of installing the horizontal perforated drain pipe showed largely 1.9~6.8 times more than the case of not installing. The drainage distance showed 1.7~1.8 times greater than sand. When a degree of consolidation is 90 %, there is no delay of consolidation in SCP and PVD improvement sections. Therefore, it is proven that the field applicability is excellent. Also, the suitable quality management criterion is presented to make use of a horizontal drains in soft ground on the basis of analysis of the physical and environmental characteristics.

시뮬레이션 시간 단계에 따른 FOWT 서지방향 항력계수 결정에 관한 CFD해석 연구 (CFD Analysis for Determining Surge-direction Drag Coefficient of FOWT based on Simulation Time Step)

  • 양호성;이영호
    • 신재생에너지
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    • 제20권2호
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    • pp.17-25
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    • 2024
  • In this study, the effect of the time step specified in a computational fluid dynamics (CFD) simulation on load response is analyzed and the drag coefficients of the floating body of floating offshore wind turbines (FOWTs) are estimated. By evaluating the error in the FOWT load response and the change in the drag-coefficient values based on the density of the time intervals, this study aims to establish a time-interval setting that minimizes the time and cost of CFD simulations for selecting drag-coefficient values. Practical CFD utilization strategies necessary for the calibration of medium-to high-fidelity analysis tools are presented. Based on a comparative analysis of CFD simulations conducted at various time intervals, the results confirmed that under a certain time interval that sufficiently considers various factors, the accuracy of the FOWT response with respect to density shows minimal differences, thereby providing an efficient utilization method for CFD simulations in FOWT design and analysis.