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81.
Behnam Ganji Abbas Z. Kouzani 《Expert systems with applications》2012,39(1):223-233
Vehicle modeling can play an important role in vehicle power train design, control and energy management investigation. This paper presents a method for vehicle power train modeling. The key feature of the method is its presentation of the dynamic of vehicle based on the road information. This ability makes the method suitable for look-ahead energy management and fuel economy optimal control problems. With the aid of a road slope database, road geometry ahead of the vehicle is extracted. A fuzzy controller is developed that receives this information and controls the velocity of the vehicle with respect to its fuel consumption. In order to maintain the operation of the combustion engine near its efficient region, the fuzzy controller commands a continuously variable transmission. Simulations are carried out using real road data. The results are presented and discussed. 相似文献
82.
Abbas Rastgoo Armen Amirian 《International Journal of Mechanics and Materials in Design》2006,3(3):253-264
This study presents three mathematical methods namely the polynomial stress function approach, the Fourier series form approach
and the approximated equations form approach for finding the stress distribution in a cantilever beam with rectangular cross
section loaded by a parabolically distributed load. By taking the stress function as a polynomial of the seventh degree, it
is attempted to find the coefficients either in complete or in full shape of the polynomial. In the Fourier series approach,
the load is discreted to unlimited series of harmonic loads and superposing resultant stresses is the affect of parabolically
distributed load on the beam. The resultant stresses are compared with some approximated stress formulas which have been provided
before. Finite element analysis are done for square, short, medium and long cantilever beams and the mathematical results
of stress distribution in five different height of the beam was compared with FEM results. It was found good results for τ
yy
and τ
xy
in all cross section of the beams and acceptable results for τ
xx
only in y = 0. It is found that discreting loads to even a limit number of harmonic loads and superposing the resultant stresses can
give the distribution of τ
yy
and τ
xy
with the acceptable precision in medium and long cantilever beams with rectangular cross section. 相似文献
83.
In this study electrochemical performance of Al and some of its alloys (Al-Zn, Al-Mg and Al-Mn) anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn>Al-Mg>Al>Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy (SEM). SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure.Electrolytic manganese dioxide (EMD) produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore (β-MnO2) by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample (EMD1) was performed well in comparison with EMD standard (EMD2) (commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S). SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface. 相似文献
84.
实时多处理器系统中基于能量节约的动态调度算法 总被引:1,自引:0,他引:1
当前处理器由于较高的能量消耗。导致处理器热量散发的提高及系统可靠性的降低,已经成为目前计算机领域较为关心的问题.然而目前一些有效降低能量消耗的技术大多针对单处理器系统,较少考虑多处理器系统.本文提出的调度算法针对多处理器系统,以最短任务优先调度为基础,结合其它有效技术,如共享空闲时间回收等,使得实时任务在其截止期内完成的同时能够有效地减低整个系统的能量消耗.针对独立任务集及具有依赖关系的任务集,本文提出两种算法:STFBA1及STFBA2(Shortest Task First—Based Algorithm).与目前所知的有效算法相比,我们的算法具有更好的性能(调度长度及能量消耗). 相似文献
85.
Amro A. El-Baz M. Kamal T. Ewida M. Abbas Shouman Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2005,7(2):78-86
The objective of this paper is to develop a systematic methodology for mass integration in drain systems and watersheds. Mass integration is a holistic approach to the tracking, transformation, and allocation of species and streams. The watershed and drain system is first discretized into reaches. The MFA model developed in part I of this work (Simulation and Application to Ammonium Management in Bahr El-Baqar Drain System) is used to describe the environmental phenomena that affect the fate and transport of targeted species and the operators that characterize the system inputs and outputs as they relate to the surroundings. Next, we develop an integration framework which encompasses sources, sinks, and interception technologies to aid in the development for nitrogen-management strategies. The simulation model was transformed into a synthesis model by introducing optimization variables and including models for the potential management strategies. The problem of minimizing negative environmental impact subject to technical, social, economic, and regulatory constraints was posed as a nonlinear optimization program whose solution identified and synthesized the most effective solution strategies. These mathematical models and management strategies were coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. Tradeoffs and sensitivity analysis were established using the devised model. The devised framework was applied to an Egyptian drain system (Bahr El-Baqar) along with the outfall to Lake Manzala. The results of the case study provide solution strategies for nitrogen management along with their technical, economic, and environmental implications. 相似文献
86.
The present study presents a methodology for detailed reliability analysis of nuclear containment without metallic liners against aircraft crash. For this purpose, a nonlinear limit state function has been derived using violation of tolerable crack width as failure criterion. This criterion has been considered as failure criterion because radioactive radiations may come out if size of crack becomes more than the tolerable crack width. The derived limit state uses the response of containment that has been obtained from a detailed dynamic analysis of nuclear containment under an impact of a large size Boeing jet aircraft. Using this response in conjunction with limit state function, the reliabilities and probabilities of failures are obtained at a number of vulnerable locations employing an efficient first-order reliability method (FORM). These values of reliability and probability of failure at various vulnerable locations are then used for the estimation of conditional and annual reliabilities of nuclear containment as a function of its location from the airport. To study the influence of the various random variables on containment reliability the sensitivity analysis has been performed. Some parametric studies have also been included to obtain the results of field and academic interest. 相似文献
87.
Due to the great advances in biomedical digital signal processing, new biometric traits have showed noticeable improvements in authentication systems. Recently, the ElectroCardioGram (ECG) and the PhonoCardioGraph (PCG) have been proposed as novel biometrics. This paper aims to review the previous studies related to the usage of the ECG and PCG signals in human recognition. In addition, we discuss briefly the most important techniques and methodologies used by researchers in the preprocessing, feature extraction and classification of the ECG and PCG signals. At the end, we introduce some future considerations that can be applied in this topic such as: the fusion between different techniques previously used, use both ECG and PCG signals in a multimodal biometric authentication system and building a prototype system for real-time authentication. 相似文献
88.
Abbas H. Sulaymon Ayad A. H. Faisal Qusey M. Khaliefa 《Mine Water and the Environment》2017,36(2):209-216
Copper and zinc ions were removed from synthetic acidic aqueous solutions onto cement kiln dust (CKD) particles in a single component system. The objectives of this study were to: distinguish between adsorption and precipitation when both mechanisms are occurring simultaneously; define their individual contributions; and consequently, specify the dominant mechanism. This was achieved by conducting a new experimental procedure for the precipitation phase that depended on CKD leachate in combination with a derivation of a simultaneous adsorption-precipitation equation. High removal efficiencies, approaching 100?%, of the Cu and Zn ions, were attained. Precipitation was the dominant mechanism for removing low concentrations of these metals, while adsorption appears to be more significant in removal of high metal concentrations. 相似文献
89.
This paper presents a comprehensive integrative framework for measuring the performance of customer relationship management (CRM) system based on a detailed empirical study of 32 Iranian internet service provider (ISP) firms. At first, by an extensive literature review and experts who have real practical experiences in the field of CRM, appropriate key performance indicators (KPIs) based on four perspectives of balanced scorecard have been extracted. Then, due to the interdependency and feedback among these KPIs, multiple criteria decision making techniques are used to evaluate CRM performance. Specifically, this study first applies the decision making trial and evaluation laboratory approach to determine the interrelated relationships among criteria, and to find the crucial central and influential factors. Then, the analytical network process method is used to obtain the criterion weights. Finally, according to these previous results, the technique for order of preference by similarity to ideal solution method is adopted to analyze the CRM performance of 32 Iranian ISP firms. The results of this study illustrated that learning and growth is the most crucial influential perspective and it would influence on the other perspectives much more. Furthermore, indicators including organization capital, human capital, customer retention process, customer perceived value, and customer expansion process play an essential role in succeeding of CRM. The results of this study can provide a comprehensive insight for managers into discerning how and through which mechanisms CRM can create merits for the organizations. 相似文献
90.
Cardamom supplementation improves inflammatory and oxidative stress biomarkers in hyperlipidemic,overweight, and obese pre‐diabetic women: a randomized double‐blind clinical trial
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