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81.
As the smart home is the end-point power consumer, it is the major part to be controlled in a smart micro grid. There are so many challenges for implementing a smart home system in which the most important ones are the cost and simplicity of the implementation method. It is clear that the major share of the total cost is referred to the internal controlling system network; although there are too many methods proposed but still there is not any satisfying method at the consumers’ point of view. In this paper, a novel solution for this demand is proposed, which not only minimizes the implementation cost, but also provides a high level of reliability and simplicity of operation; feasibility, extendibility, and flexibility are other leading properties of the design. 相似文献
82.
M.H. Heydari M.R. Hooshmandasl F.M. Maalek Ghaini F. Fereidouni 《Engineering Analysis with Boundary Elements》2013,37(11):1331-1338
In this paper, the two-dimensional Legendre wavelets are applied for numerical solution of the fractional Poisson equation with Dirichlet boundary conditions. In this way, a new operational matrix of fractional derivative for the Legendre wavelets is derived and then this operational matrix has been employed to obtain the numerical solution of the above-mentioned problem. The main characteristic behind this approach is that it reduces such problems to those of solving a system of algebraic equations which greatly simplifies the problem. The convergence of the two-dimensional Legendre wavelets expansion is investigated. Also the power of this manageable method is illustrated. 相似文献
83.
Jafar Heydari Reza Baradaran Kazemzadeh S. Kamal Chaharsooghi 《The International Journal of Advanced Manufacturing Technology》2009,40(11-12):1206-1215
Lead time (LT) is a core parameter that varies and affects all supply chain (SC) partners. LT uncertainty is known as a kind of supply uncertainty in the SC literature which attracts attention of many researchers. In this paper, impact of LT variability in a serially connected supply chain with 4 levels is investigated. The study includes two main stages: development of a structural model and testing the structural relations by using simulated data. Simulation makes it possible to remove effects of intervener variables in order to measure pure impact of LT uncertainty on SC. Regarding this matter, a structural relationship model with three hypotheses about direct and indirect impact of LT uncertainty on supply chain inventories have been developed. To test the proposed structural relations, simulated data were used. The results of the study show that by increasing the lead time variance, order variances increase while no impact on the bullwhip is observed, i.e. the order variances increase uniformly throughout the entire SC. Furthermore, results show that the increase in the lead time variance will lead to inventory fluctuations. One practical recommendation of this study is to apply an investment strategy to reduce the lead time uncertainty. 相似文献
84.
The nitridation of SS304 surfaces is obtained by irradiating nitrogen ions from Amirkabir plasma focus device, which use multiple focus deposition shots at optimum distance 10 cm from the anode. The Vickers Micro-Hardness values are improved more than twice for the nitrided samples comparing to the nonnitrided ones. The X-ray diffraction (XRD) analysis is carried out in order to explore the phase changes in the near surface structure of the metals. The results of Scanning Electron Microscopy (SEM) indicate changes in surface morphology which are the emergence of smooth and uniform film on the surface of the nitrided metals. 相似文献
85.
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87.
Mahdi Heydari‐Meybodi Majid R. Ayatollahi Mohammad Dehghany Filippo Berto 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(3):732-742
In this study, the rupture load in rubbers weakened by sharp V‐notch is investigated under mode I loading. To this end, first, mode I fracture tests are performed on V‐notched samples made of styrene‐butadiene rubbers and the corresponding rupture loads are obtained. Then, the effective stretch (ES) criterion, which was recently developed by the present authors for rupture assessment of cracked rubber parts, is extended and used for the V‐notched rubbers. It is shown that similar to cracked rubbers, the state of stress near the notch tip is also nearly uniaxial. By employing the ES criterion, the critical displacements corresponding to the rupture in the tested samples are calculated. Finally, the predictions of the criterion are compared with the corresponding experimental values, and good consistency is shown to exist. 相似文献
88.
A. Mardani M.R. Hooshmandasl M.H. Heydari C. Cattani 《Computers & Mathematics with Applications》2018,75(1):122-133
In this paper, an efficient and accurate meshless method is proposed for solving the time fractional advection–diffusion equation with variable coefficients which is based on the moving least square (MLS) approximation. In the proposed method, firstly the time fractional derivative is approximated by a finite difference scheme of order and then the MLS approach is employed to approximate the spatial derivative where time fractional derivative is expressed in the Caputo sense. Also, the validity of the proposed method is investigated in error analysis discussion. The main aim is to show that the meshless method based on the MLS shape functions is highly appropriate for solving fractional partial differential equations (FPDEs) with variable coefficients. The efficiency and accuracy of the proposed method are verified by solving several examples. 相似文献
89.
In this paper, a new computational method based on the second kind Chebyshev wavelets (SKCWs) together with the Galerkin method is proposed for solving a class of stochastic heat equation. For this purpose, a new stochastic operational matrix for the SKCWs is derived. A collocation method based on block pulse functions is employed to derive a general procedure for forming this matrix. The SKCWs and their operational matrices of integration and stochastic Itô-integration are used to transform the under consideration problem into the corresponding linear system of algebraic equations which can be simply solved to achieve the solution of the problem. The proposed method is very convenient for solving such problems, since the initial and boundary conditions are taken into account automatically. Moreover, the efficiency of the proposed method is shown for some concrete examples. The results reveal that the proposed method is very accurate and efficient. 相似文献
90.
In this research, four cholines supported on core–shell iron oxides, Fe2O3@MgO@Ch.OAc (choline acetate), Fe2O3@MgO@Ch.OH (choline hydroxide), Fe3O4@Ch.OAc, Fe3O4@Ch.OH, were synthesized. The synthesized catalysts were tested in 1,2,3-triazoles synthesis by the reaction of nitromethane, aldehyde, and benzyl azide in EtOH as a green solvent. Among four synthesized heterogeneous catalysts, the Fe2O3@MgO@ch.OAc showed superior catalytic activity for the reaction and afforded the desired triazoles in good isolated yields under mild reaction conditions.
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