scholarly journals Multi-reservoir system management under alternative policies and environmental operating conditions

2018 ◽  
Vol 49 (6) ◽  
pp. 1817-1830 ◽  
Author(s):  
Amin Hassanjabbar ◽  
Bahram Saghafian ◽  
Saeed Jamali
Keyword(s):  
Optimization Model ◽  
Maximum Flow ◽  
Environmental Flow ◽  
Operating Conditions ◽  
Performance Criteria ◽  
Reservoir System ◽  
Range Of Variability Approach ◽  
Hydropower Production ◽  
The Difference ◽  
And Performance

Abstract In this paper, alternative reservoir operation models under different environmental operating conditions were developed to analyze the impacts of applying different policies in a multi-reservoir system in order to balance human and environmental requirements. Three scenarios/models were developed under four sub-scenarios/operating conditions. The scenarios were: (1) an optimization model to maximize the hydropower production, (2) an optimization model to minimize the squared of the difference between the release and need, (3) a simulation model under the Hydropower Standard Operating Policy. The sub-scenarios were developed as follows: (i) no environmental flow, (ii) minimum environmental flow, (iii) environmental flow bounded by the minimum and maximum flow, and (iv) maximum environmental flow. Hydropower production and system performance criteria were calculated and compared in all cases. Moreover, the Range of Variability Approach was used to assess the hydrological alterations of each of the 12 cases. The results in a two reservoir cascade of Seimare-Karkheh, located within the Karkheh River Basin in Iran, showed that sub-scenario 3 performed best in all three scenarios. Further comparison indicated that scenario 1, under sub-scenario 3, was a good compromise solution, as it provided adequate hydropower production and performance criteria and the least hydrological alterations.

Performance and Development of a Miniature Rotary Shaft Pump

2005 ◽  
Vol 127 (4) ◽  
pp. 752-760 ◽  
Author(s):  
Danny Blanchard ◽  
Phil Ligrani ◽  
Bruce Gale
Keyword(s):  
Flow Rate ◽  
Pressure Rise ◽  
Electronics Cooling ◽  
Maximum Flow ◽  
Operating Conditions ◽  
Working Fluid ◽  
Hydraulic Efficiency ◽  
Potential Applications ◽  
Total Analysis ◽  
And Performance

The development and performance of a novel miniature pump called the rotary shaft pump (RSP) is described. The impeller is made by boring a 1.168 mm hole in one end of a 2.38 mm dia shaft and cutting slots in the side of the shaft at the bottom of the bored hole such that the metal between the slots defines the impeller blades. The impeller blades and slots are 0.38 mm tall. Several impeller designs are tested over a range of operating conditions. Pump performance characteristics, including pressure rise, hydraulic efficiency, slip factor, and flow rate, are presented for several different pump configurations, with maximum flow rate and pressure rise of 64.9ml∕min and 2.1 kPa, respectively, when the working fluid is water. Potential applications include transport of biomedical fluids, drug delivery, total analysis systems, and electronics cooling.

scholarly journals Calibration of the hydrological model GR4J from potential evapotranspiration estimates by the Penman-Monteith and Oudin methods in the Ouémé watershed (West Africa)

2020 ◽  
Vol 383 ◽  
pp. 163-169
Author(s):  
Domiho Japhet Kodja ◽  
Arsène J. Sègla Akognongbé ◽  
Ernest Amoussou ◽  
Gil Mahé ◽  
E. Wilfrid Vissin ◽  
...  
Keyword(s):  
Hydrological Modeling ◽  
Hydrological Model ◽  
Potential Evapotranspiration ◽  
Daily Rainfall ◽  
Performance Criteria ◽  
Economic Activities ◽  
Wet Season ◽  
Daily Data ◽  
The Difference ◽  
And Performance

Abstract. The Ouémé watersheds at Bétérou and Bonou has been recently facing increased sensitivity to extreme hydroclimatic phenomena that occurred by flooding or drought events. In the same time, the population growth and the related socio-economic activities increased the pressure state on water resources. In this context, hydrological modeling is an important issue and this study aims at analyzing the calibration of the hydrological model GR4J based on PET Penman-Monteith and Oudin methods. Daily rainfall, Penman-Monteith and Oudin evapotranspiration and daily data flow from the Bétérou and Bonou hydrometric stations on the Ouémé Basin have been implemented in the GR4J model over the period 1971 to 2010. Oudin PET values are slightly higher than the Penman-Monteith PET ones. However, the difference between the two PET methods have only few impacts on the optimization and performance criteria of the GR4J model. The Nash values ranges from 0.83 to 0.91 in Bonou, and 0.52 to 0.70 in Bétérou for the calibration in dry period, while in validation, they are 0.59 to 0.78 in Bétérou, and 0.56 to 0.88 in Bonou in wet season. In view of these results, with the two PET methods used which do not result from the same climatic variables, it should be said that the formulation of PET has only few impacts on the results of GR4J for these tropical basins.

scholarly journals Defining and Diagnosing Performance Standards

2021 ◽  
Vol 11 (4) ◽  
pp. 5609-5628
Author(s):  
Maha Jawad Kadam ◽  
Zaman Imad Abd AL Ameer
Keyword(s):  
Competitive Advantage ◽  
Performance Indicators ◽  
Performance Standards ◽  
Performance Criteria ◽  
Actual Performance ◽  
Historical Method ◽  
The Difference ◽  
And Performance

The current research seeks to study and analyze performance indicators and standards and its variables, the research relied on the historical method in studying the previous indicators by returning to the measures related to indicators and performance standards presented by a different group of writers and researchers, performance criteria were analyzed to determine the level and size of the gap between actual performance and planned performance. The study reached a set of conclusions, the most important of which is that the concept of Performance and performance indicators are topics that are characterized by intellectual and cognitive richness. Perhaps the reason for this difference is due to the difference in the fields and areas in which researchers studied the concept and performance indicators. As well as the cognitive, cultural and intellectual differences of researchers in this concept. As for the most important recommendations of the research, it referred to the invitation of organizations to strive hard in determining their own performance indicators. The organization can stand alone from the competing organizations in defining special indicators to measure its performance that will enable it to achieve a competitive advantage.

Flow Analysis of Axial Compressor AV63-15 Variable Stator Simulation

2012 ◽  
Vol 532-533 ◽  
pp. 474-478
Author(s):  
Wei Hua Cheng ◽  
Mian Chang Li ◽  
Chuan Peng Li
Keyword(s):  
Flow Analysis ◽  
Three Dimensional ◽  
Axial Compressor ◽  
Axial Flow ◽  
Operating Conditions ◽  
Axial Flow Compressor ◽  
Air Supply ◽  
The Difference ◽  
And Performance ◽  
Flow Compressor

This paper conducts numerical simulation to a 15-stage civil axial flow compressor and obtains its main parameters distribution and performance curve by a full three-dimensional viscid flow computation software. The computation result indicates that, the developed axial flow compressor meets the anticipated design requirements, and satisfies the customers’ indicators. Under the designed compression ratio, the difference between the maximum air supply quantity in summer and the minimum air supply quantity in winter is 22%. By comparing the operating conditions and data analysis, obtained the change trend of axial velocity, static pressure and temperature, and Ma, and discovered that, under opening of 48° and outlet back pressure of 550KPa, flow separation occurred on the section of machine set close to hud, which indicated that operating condition was close to surging condition.

Performance and Development of a Miniature Rotary Shaft Pump (RSP)

2004 ◽  
Author(s):  
Daniel B. Blanchard ◽  
Phillip M. Ligrani ◽  
Bruce K. Gale
Keyword(s):  
Flow Rate ◽  
Pressure Rise ◽  
Electronics Cooling ◽  
Maximum Flow ◽  
Operating Conditions ◽  
Working Fluid ◽  
Pump Performance ◽  
Potential Applications ◽  
Total Analysis ◽  
And Performance

The development and performance of a novel miniature pump called the rotary shaft pump (RSP) is described. The impeller is made by boring a hole in one end of a shaft, and cutting slots in the side of the shaft at the bottom of the bored hole, such that the metal between the slots defines the impeller blades. Several impeller designs are tested over a range of operating conditions. Pump performance characteristics, including pressure rise, efficiency, slip factor, and flow rate are presented for several different pump configurations, with maximum flow rate and pressure rise of 64.9ml/min, and 2.1kPa, respectively, when the working fluid is water. Potential applications include transport of biomedical fluids, drug delivery, total analysis systems, and electronics cooling.

scholarly journals Scheduling of undergraduate thesis examination: a case study in Industrial Engineering Department of Universitas Sebelas Maret

2019 ◽  
Vol 15 (S1) ◽  
pp. 209-221
Author(s):  
Cucuk Nur Rosyidi ◽  
Endah Budiningsih ◽  
Wakhid Ahmad Jauhari
Keyword(s):  
Optimization Model ◽  
Industrial Engineering ◽  
Performance Criteria ◽  
Programming Approach ◽  
Engineering Department ◽  
The Difference ◽  
Total Difference ◽  
Two Stages ◽  
Undergraduate Thesis

Abstract Undergraduate thesis examination in Industrial Engineering Department of Universitas Sebelas Maret conducted through two stages, namely intermediate and final examination. Currently, the scheduling process of such examinations is done by the undergraduate thesis coordinator manually without certain systematic method or approach. In this paper, we develop an optimization model for the examinations scheduling considering several factors, namely the number of lecturers that must attend the examinations, the availability of rooms for examinations, the availability of each lecturer, and the assignment distributions. The model uses integer programming approach. Two performance criteria are used in the model, namely the difference between the number of each lecturer’s assignment with the average number of lecturer assignments and the number of penalties from the assignment of lecturers on certain time slot. The developed model is able to solve the scheduling problem more efficiently than manual scheduling done by thesis coordinator. The optimal solutions from the optimization model show a total difference in the assignment of lecturer with an average of 29.6 and a penalty of 0.

scholarly journals Development of an Optimal Model for the Xiluodu-Xiangjiaba Cascade Reservoir System Considering the Downstream Environmental Flow

2020 ◽  
Vol 12 (3) ◽  
pp. 966
Author(s):  
Lingquan Dai ◽  
Huichao Dai ◽  
Haibo Liu ◽  
Yu Wang ◽  
Jiali Guo ◽  
...  
Keyword(s):  
Power Generation ◽  
Environmental Flow ◽  
Reservoir Model ◽  
Optimal Model ◽  
Nsga Ii ◽  
Jinsha River ◽  
Reservoir System ◽  
Operation Conditions ◽  
Ecological Protection ◽  
Range Of Variability Approach

To explore the influence of the Xiluodu-Xiangjiaba cascade reservoir system on the appropriate environmental flow (AEF) of the Jinsha River, a multiobjective optimal cascade reservoir model was established with the aim of maximizing power generation while minimizing the downstream degree of AEF alteration. The AEF was determined using the range of variability approach (RVA). The optimal model was solved using an improved version of NSGA-II called INSGA2-DS. Inflows in typical normal and dry years were selected for optimization. The results show that in a normal year, power generation can be increased by 1.28% compared with that under the current regular operation conditions by prioritizing the maximization of power generation, in which case the degree of AEF alteration will increase by 13.86%. In contrast, the degree of AEF alteration will decrease by 22.53% if ecological protection is prioritized, but power generation will decrease by 0.62%. Similarly, in a dry year, power generation can be increased by 1.76% compared with that under the current regular operation conditions to maximize economic benefit, in which case, the degree of AEF alteration will increase by 4.95%. By contrast, the degree of AEF alteration can be decreased by 13.70% if the objective is AEF minimization, but power generation will decrease by 0.48%. These research results provide useful information for the formulation of ecological operation schemes involving cascade reservoirs on the Jinsha River.

A Modification of the Payne-Jones Method of Identifying Abnormal Differences in WISC-R Performance and Verbal IQ's

1996 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Louis M. Hsu
Keyword(s):  
Full Scale ◽  
True Score ◽  
Verbal Iq ◽  
Score Difference ◽  
The Difference ◽  
And Performance

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.

ASSESSMENT OF HYDROLOGICAL CHANGES IN THE ŠUŠVĖ RIVER

2015 ◽  
Author(s):  
Gražina ŽIBIENĖ ◽  
Alvydas ŽIBAS ◽  
Goda BLAŽAITYTĖ
Keyword(s):  
Hydrological Regime ◽  
Maximum Flow ◽  
Environmental Flow ◽  
Physical Structure ◽  
River Channels ◽  
Hydrologic Alteration ◽  
Water Conditions ◽  
Flow Components ◽  
The Impact ◽  
Large Floods

The construction of dams in rivers negatively affects ecosystems because dams violate the continuity of rivers, transform the biological and physical structure of the river channels, and the most importantly – alter the hydrological regime. The impact on the hydrology of the river can occur through reducing or increasing flows, altering seasonality of flows, changing the frequency, duration and timing of flow events, etc. In order to determine the extent of the mentioned changes, The Indicators of Hydrologic Alteration (IHA) software was used in this paper. The results showed that after the construction of Angiriai dam, such changes occurred in IHA Parameters group as: the water conditions of April month decreased by 31 %; 1-day, 3-days, 7-days and 30-days maximum flow decreased; the date of minimum flow occurred 21 days later; duration of high and low pulses and the frequency of low pulses decreased, but the frequency of high pulses increased, etc. The analysis of the Environmental Flow Components showed, that the essential differences were recorded in groups of the small and large floods, when, after the establishment of the Šušvė Reservoir, the large floods no longer took place and the probability of frequency of the small floods didn’t exceed 1 time per year.

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