Terms Of Average Efficiency Research Articles

Dwarf Mongoose Optimizer for Optimal Modeling of Solar PV Systems and Parameter Extraction

This article presents a modified intelligent metaheuristic form of the Dwarf Mongoose Optimizer (MDMO) for optimal modeling and parameter extraction of solar photovoltaic (SPV) systems. The foraging manner of the dwarf mongoose animals (DMAs) motivated the DMO’s primary design. It makes use of distinct DMA societal groups, including the alpha category, scouts, and babysitters. The alpha female initiates foraging and chooses the foraging path, bedding places, and distance travelled for the group. The newly presented MDMO has an extra alpha-directed knowledge-gaining strategy to increase searching expertise, and its modifying approach has been led to some extent by the amended alpha. For two diverse SPV modules, Kyocera KC200GT and R.T.C. France SPV modules, the proposed MDMO is used as opposed to the DMO to efficiently estimate SPV characteristics. By employing the MDMO technique, the simulation results improve the electrical characteristics of SPV systems. The minimization of the root mean square error value (RMSE) has been used to compare the efficiency of the proposed algorithm and other reported methods. Based on that, the proposed MDMO outperforms the standard DMO. In terms of average efficiency, the MDMO outperforms the standard DMO approach for the KC200GT module by 91.7%, 84.63%, and 75.7% for the single-, double-, and triple-diode versions, respectively. The employed MDMO technique for the R.T.C France SPV system has success rates of 100%, 96.67%, and 66.67%, while the DMO’s success rates are 6.67%, 10%, and 0% for the single-, double-, and triple-diode models, respectively.

Effect of Fiscal Expenditure for Supporting Agriculture on Agricultural Economic Efficiency in Central China—A Case Study of Henan Province

The policy guidance and financial support for industrial development from public finance provide an important guarantee for practicing green and circular development of agriculture. By sorting out the development context of fiscal support for agriculture in Henan province in different historical stages, this paper analyzes the development status of fiscal support for agriculture and the agricultural circular economy in the province. Relying on data envelopment analysis (DEA), it measures the efficiency of the agricultural circular economy in Henan province in 2013–2019 using the Charnes, Cooper, and Rhodes (CCR) model, the Banker, Charnes, and Cooper (BCC) model, and super-efficiency DEA models and empirically analyzes the effect of the fiscal expenditure for supporting agriculture on the efficiency of the agricultural circular economy using the fixed effect model. According to the results, (1) the expenditure on comprehensive agricultural development of Henan Province was mainly supported by the government’s fiscal funds to such a degree that the proportion of fiscal funds from the central government exceeded 40% throughout the year. Particular stress was laid on the land governance projects of comprehensive agricultural development in the province. (2) The overall development level of the agricultural circular economy in Henan Province was low, and there were considerable gaps between cities (counties). Under the super-efficiency DEA model, only Hebi City, which ranked first in terms of average efficiency, achieved relative efficiency. (3) The fiscal expenditure for supporting agriculture had a positive incentive effect on the efficiency of the agricultural circular economy in Henan province, and the incentive effect became more significant after the time effect was controlled. Accordingly, this paper puts forward some targeted policy suggestions, which enrich the existing research on fiscal support for agriculture and agricultural circular economy at both theoretical and practical levels.

Derivative free methodologies for circuit worst case analysis

In this paper, a new derivative-free method for Worst Case Analysis (WCA) of circuit design is defined. A WCA of a device can be performed by solving a particular minimization problem where the objective function values are obtained by a simulation code and where some variables are subject to a spherical constraint and others to box constraints. In order to efficiently tackle such a problem, the paper defines a new DF algorithm which follows a two blocks Gauss Seidel approach, namely it alternates an approximated minimization with respect to the variables subject to the spherical constraint with an approximated minimization respect to the variables subject to the box constraints. The algorithm is described and its global convergence properties are analyzed. Furthermore it is tested in the WCA of a MOSFET operational amplifier and its computational behaviour is compared with the one of the efficient optimization tool of the WiCkeD suite for circuit analysis. The obtained results seem to indicate that the proposed algorithm is promising in terms of average efficiency, accuracy and robustness.

MEASURING THE EFFICIENCY OF BANKS: THE BOOTSTRAPPED I-DISTANCE GAR DEA APPROACH

The efficiency of the banking sector, particularly in developing countries, has captivated the attention of various researchers. Contributing to this issue, we present the results of in-depth analysis of the efficiency of Serbian banks during the period 2005–2016. Unlike previous papers evaluating the efficiency of South-Eastern European banks, we emphasize the importance of applying weight restrictions in Data Envelopment Analysis (DEA). The aim is to incorporate every aspect of a decision-making unit’s performance to avoid misevaluation of a bank’s efficiency. As a possible remedy to the issue, a bootstrapped I-distance is suggested as a statistically sound framework for determining weight bounds in the Global Assurance Region (GAR) DEA model. In terms of average efficiency, the banking sector of Serbia exhibits an improving trend over the period analyzed. The results show how banks can be evaluated when the impact of all the operating inputs and outputs are properly factored into the study.

Coupled Multipoint Shape Optimization of Runner and Draft Tube of Hydraulic Turbines

This paper suggests a method of simultaneous multi-objective shape optimization of hydraulic turbine runner and draft tube (DT) with the objective to increase turbine efficiency in wide range of operating points (OPs). Runner and DT are the main sources of energy losses in hydraulic turbines. Coupling runner and DT in computational fluid dynamics (CFD) analysis enables correct statement of boundary conditions for efficiency evaluation, while simultaneous variation of these components allows more flexible adjustment of flow passage geometry. Detailed runner parameterization with 28 free geometrical parameters and DT parameterization with nine free parameters are given. Optimization problem is solved using multi-objective genetic algorithm (MOGA). For each variation of runner and DT shapes, flow field in wicket gate (WG), runner, and DT is simulated using steady-state Reynolds-Averaged Navier–Stokes (RANS) equations with k-e turbulence model. Energy-based boundary conditions are used for the calculations, allowing determination of efficiency of the whole turbine in correspondence with International Electrotechnical Commission (IEC) standard. Formulations of multiple OP efficiency objective functions and constraints are discussed in detail. To demonstrate the advantages of simultaneous runner and DT variation, two optimization problems are solved for a medium specific speed Francis turbine. Namely, single runner and coupled “runner–DT” optimizations are carried out. It is shown that optimized runner–DT geometry outperforms the result of single runner optimization by about 0.3% in terms of average efficiency, showing the potential of the developed approach to improve multiregime turbine characteristics in practical design optimization problems.

El amplificador de potencia Doherty con etapa de pre-amplificación

Este artículo presenta el concepto general del amplificador de potencia Doherty, resaltando su superioridad, en términos de eficiencia promedio, con respecto a amplificadores de una etapa. Además, se presenta la posibilidad de incluir etapas de pre-amplificación en las ramas del amplificador Doherty, con el objetivo de incrementar su ganancia.

Pulse-Width Modulated CMOS Power Amplifiers

The relentless scaling of CMOS circuits has led to the possibility of completely integrated RF-SOCs, including the PA. A CMOS PA likely will not achieve the same peak output power and efficiency as its counterpart in a III-V technology. It is conceivable, however, that by taking advantage of the strengths of CMOS switching devices, future CMOS PAs can win in terms of average efficiency and, perhaps more importantly, cost. PWM techniques offer one such potential solution, owing to the level of digital integration possible. Because of this, PWM PAs are expected to scale well, and the dynamic range possible with such amplifiers should increase as well because the faster devices will be able to process signals with smaller pulse widths.

Efficiency of Banks in Croatia: A DEA Approach

An understanding of a bank's relative performance compared to the market over a period of time is important for analysts, practitioners and policymakers alike. In this paper we analyze bank efficiency in Croatia between 1995 and 2000 by using the Data Envelopment Analysis (DEA). We find that foreign-owned banks are on average most efficient; that new banks are more efficient than old; and that smaller banks are globally efficient, but large banks are efficient when we allow for variable- returns- to- scale. We also find strong equalization in terms of average efficiency in the Croatian banking market, both between peer groups and within peer groups of banks.

Measuring Value in MBA Programmes

This paper presents an application of data envelopment analysis to measure value added in Master of Business Administration (MBA) education in the US. The paper focuses on the MBA programme as an example of a value-adding process in education and demonstrates how such programmes may be evaluated in terms of their efficiency in providing value to students. Results of experiments with various combinations of input and output measures are reported. The top 20 MBA programmes do not seem to be different from the second 20 in terms of average efficiency.

On the relative efficiency of alternative modes of producing a public sector output: The case of the developmentally disabled

This paper examines the relative efficiency of alternative methods of producing care for the developmentally disabled. A linear programming framework is used to construct a production frontier which allows measurement of relative efficiency among institutions in the sample. Tests are performed to detect influential observations in the data which might result from measurement error which could distort the efficiency measures. Different types of institutions are compared in terms of average efficiency. Policy implications of the analysis are discussed in the concluding section.