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101.
Workplace spirituality has gained attention as it is proven to be a contributor to organizational performance improvement. This paper aims to assess the impact of human resource spirituality on the success of organizational strategic change projects. The success of the projects is measured by the well-known criterion of deviation from the planned budget cost. Data collection is based on a questionnaire survey of 252 personnel in 36 large and medium-scale organizational change projects in power industry. The paper proposes an integrated algorithm of fuzzy data envelopment analysis (FDEA) and adaptive network-based fuzzy inference system (ANFIS) for measuring the pure effect of human resource spirituality on the success of organizational change projects in the power industry. It also achieves a verified tool capable of addressing complexity, nonlinearity, ambiguity, and fuzziness for measuring spirituality of human resources in the projects. Results show that spirituality of the project team has a significant effect on project success.  相似文献   
102.
This study has been carried out to investigate the incorporation of Iron(II) sulfate as an additive of electrolyte on formed AA1010 aluminum alloy, using plasma electrolytic oxidation method in silicate-based electrolytes containing Iron(II) sulfate. In order to fabricate nanocomposite coating, silicon nitride nanopowder was added to electrolyte. The effects of iron(II) sulfate additive on the voltage-time trend, microstructure, compositions, wear, and corrosion resistances of PEO coatings were investigated. In addition, current density and concentration of additive were studied as parameters that were effective on coating. Results showed that although FeSO4 enters to the coating structure, but it does not develop a new phase. The corrosion and wear behavior of coated samples with FeSO4 indicate an improvement as compared to those without additive.  相似文献   
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104.
Cognitive radios (CRs) have been recently proposed for the problem of spectrum scarcity. The principle of CRs?? operation is based on the opportunistic access to the frequency spectrum mainly dedicated to primary users (PUs). The statistical time pattern of PUs?? channel usage and arrival can affect the usability of specific frequency bands for CRs. In this note, the effect of the arrival rate and channel holding time of PUs on the available times for CRs is analyzed. To this end, first, based on Poissonian arrivals, the available time for CRs is calculated. Then, assuming a gamma distribution for the inter-arrival times and a uniform distribution of channel holding time of PU in these intervals, the probability density function and moments of the available time for CRs are derived. Next, the effect of PUs statistical parameters on the average number of packets and the average symbol rate that a CR can transmit is analyzed. Also, taking that CR needs at least T seconds, the average waiting time is calculated.  相似文献   
105.
106.
One of the greatest challenges while working on image segmentation algorithms is a comprehensive measure to evaluate their accuracy. Although there are some measures for doing this task, but they can consider only one aspect of segmentation in evaluation process. The performance of evaluation measures can be improved using a combination of single measures. However, combination of single measures does not always lead to an appropriate criterion. Besides its effectiveness, the efficiency of the new measure should be considered. In this paper, a new and combined evaluation measure based on genetic programming (GP) has been sought. Because of the nature of evolutionary approaches, the proposed approach allows nonlinear and linear combinations of other single evaluation measures and can search within many and different combinations of basic operators to find a good enough one. We have also proposed a new fitness function to make GP enable to search within search space effectively and efficiently. To test the method, Berkeley and Weizmann datasets besides several different experiments have been used. Experimental results demonstrate that the GP based approach is suitable for effective combination of single evaluation measures.  相似文献   
107.
In this study, thermal and small-scale effects on the flapwise bending vibrations of a rotating nanoplate, which can be the basis of nano-turbine design, have been analyzed. The nano-turbine is made of an orthotropic nanoplate with a setting angle that is modeled based on the classical plate theory (CPT) with cantilever boundary conditions. The axial forces are also included in the model as the true spatial variation due to the rotation and temperature change. The governing equations and boundary conditions are derived according to Hamilton's principle and the governing equations are solved with the aid of the generalized differential quadrature method. The effects of small-scale parameter, nondimensional angular velocity, temperature change, and setting angles in the first four nondimensional frequencies are discussed. Due to the consideration of the rotating effects, results of this study are applicable in nano-machines, such as nano-motors, nano-rotor, and other rotating nano-structures. Also, by considering the effect of thermal loading on rotation of a nanoplate, the results are useful in the design of nano-turbines.  相似文献   
108.
Metallurgical and Materials Transactions A - In this study, mechanisms of microstructural evolution during hot deformation of Ti-1100 were investigated by EBSD analysis. Misorientation angle...  相似文献   
109.
In this paper a novel low voltage (LV) very low power (VLP) class AB current output stage (COS) with extremely high linearity and high output impedance is presented. A novel current splitting method is used to minimize the transistors gate–source voltages providing LV operation and ultra high current drive capability. High linearity and very high output impedance are achieved employing a novel resistor based current mirror avoiding conventional cascode structures to be used. The operation of the proposed COS has been verified through HSPICE simulations based on TSMC 0.18 μm CMOS technology parameters. Under supply voltage of ±0.7 V and bias current of 5 μA, it can deliver output currents as high as 14 mA with THD better than ?53 dB and extremely high output impedance of 320 MΩ while consuming only 29 μW. This makes the proposed COS to have ultra large current drive ratio (Ioutmax/Ibias or the ratio of peak output current to the bias current of output branch transistors) of 2800. By increasing supply voltage to ±0.9 V, it can deliver extremely large output current of ±24 mA corresponding to 3200 current drive ratio while consuming only 42.9 μW and exhibiting high output impedance of 350 MΩ. Interestingly, the proposed COS is the first yet reported one with such extremely high output current and a THD even less than ?45 dB. Such ultra high current drive capability, high linearity and high output impedance make the proposed COS an outstanding choice for LV, VLP and high drive current mode circuits. The superiority of the proposed COS gets more significance by showing in this work that conventional COS can deliver only ±3.29 mA in equal condition. The proposed COS also exhibits high positive and negative power supply rejection ratio (PSRR+/PSRR?) of 125 dB and 130 dB, respectively. That makes it very suitable for LV, VLP mixed mode applications. The Monte Carlo simulation results are provided, which prove the outstanding robust performance of the proposed block versus process tolerances. Favorably the proposed COS resolves the major limitation of current output stages that so far has prevented designing high drive current mode circuits under low supply voltages. In brief, the deliberate combination of so many effective novel methods presents a wonderful phenomenal COS block to the world of science and engineering.  相似文献   
110.
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