Abstract Different flow field designs are known for vanadium redox-flow batteries (VFB). The best possible design to fulfil a variety of target parameters depends on the boundary conditions. Starting from an exemplary interdigitated design, its channel and land dimensions varied investigate impact pressure drop, volume, uniformity limiting current density. To find desirable compromise between t...

This paper adopts two mathematical approaches, data envelopment analysis (DEA) and grey relation analysis (GRA) to measure DEA efficiency using the sample of 69 listed US internet companies. A total of 40 indicators were initially selected for the efficiency evaluation, with 21 related to DEA-input indicators and 19 to DEAoutput indicators. Eight representative indicators selected using GRA are...

In this paper, grey system theory and DEA are combined to establish a grey DEA model. In traditional DEA model, Input and output values of decision-making groups are all real numbers and real variables. They are replaced by grey numbers and grey variables in grey DEA model respectively. Using positioning solution method of grey linear programming, we prove the necessary condition for grey effec...

The spectroscopic and electrochemical properties of a series of four RuII polypyridyl complexes are reported. Compounds of the form [Ru(dmb)x(dea)3-x] (x ) 0-3), where dmb is 4,4′-dimethyl-2,2′-bipyridine and dea is 4,4′-bis(diethylamino)-2,2′-bipyridine, have been prepared and studied using static and time-resolved electronic and vibrational spectroscopies as a prelude to femtosecond spectrosc...

Abstract Asphalt mixture is a combination of aggregate and asphalt. Sinabung eruption volcanic ash produced many negative impact on health the environment. So that needs to be done in order study can used road pavement, especially Concrete purpose this determine effect comparison filler sinabung - Binder Course. This research was laboratory experimental nature with asphalt level variation 5%, 5...

An algorithm stral:egy is proposed for use with the assurance region (AR) approach in data envelopment analysis (DEA). The strategy addressed in this study characterizes and cla.5sifies all decision making units (DMUs) into several subsets, using the revised simplex method of linear programming. Then, each DMU subset is solved by a different algorithm. Experimental studies consisting of randoml...

In many data envelopment analysis (DEA) applications, the analyst always confronts the difficulty that the selected data set is not suitable to apply traditional DEA models for their poor discrimination. This paper presents an approach using Shannon’s entropy to improve the discrimination of traditional DEA models. In this approach, DEA efficiencies are first calculated for all possible variabl...

We have observed charge trapping during constant voltage stress in Hf-based highdielectrics at deep traps as well as at the shallow traps. VFB and leakage current dependence on these deep traps further suggest that trapping at deep levels inhibits fast VT recovery. The earlier findings where charge trapping seemed to be very transient due to the presence of a large number of shallow traps and t...

In this paper, the electrical and optical properties of undoped and in-situ doped amorphous SiC films are presented. The films are prepared by using mixture of methane (CH4) and silane (SiH4) as C and Si sources, phosphine (PH3) and diborane (B2H6) as doping gases. The bandgap, optical constant and absorption coefficient of the films are measured and a strong dependence on the layer composition...

Data envelopment analysis (DEA) has gained great popularity in environmental performance measurement because it can provide a synthetic standardized environmental performance index when pollutants are suitably incorporated into the traditional DEA framework. Past studies about the application of DEA to environmental performance measurement often follow the concept of radial efficiency measures....