Hydropower energy generation depends on the available water resources. Therefore, planning and operation of the water resource systems are paramount tasks for energy management. Since reservoirs are one of the important components of water resources systems, extracting optimal operating policies for proper management of energy generated from these systems is an imperative step. Optimizing reservoir system operation (ORSO) is a non-linear, large-scale, and non-convex problem with a large number of constraints and decision variables. To solve ORSO problem effectively, a robust diversity-based, sine-cosine algorithm (RDB-SCA) is developed in the present study by introducing several strategies to balance the global exploration and local exploitation ability and to achieve accurate and reliable solutions. An efficient linear operation rule is coupled with the RDB-SCA to maximize the energy generation. The proposed method is then applied to a real-world, multi-reservoir system to extract optimal operational policies and, consequently, maximize the energy production. It is shown that the RDB-SCA is able to generate 24, 14, and 6% more energy than the original SCA, respectively for 2-, 3-, and 4-reservoir systems. The present findings are useful to suggest guidelines for efficient operation of hydropower multi-reservoir systems. This paper is supported by https://imanahmadianfar.com/codes.
Railway Engineering Science - Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success... 相似文献
Obtained results of micro and nano studies reveal that bismuth refines the silicon in which the flake silicon changed to lamellar structure with reduction in twin spacing from 160 to 75 nm. Bismuth segregates towards the inter-dendritic regions and decreases the Al-Si contact angle resulting in suppression of the silicon growth causing refinement of the eutectic structure. Increased recalescence temperature and time confirmed that the refinement effect is attributed to the growth stage. 相似文献
Scaffolds and their features play a central role in tissue engineering; so this study is based on the production of a series of electrospun PHB/Chitosan/nBG nanocomposite scaffolds with 9 wt% polyhydroxybutyrate, 10, 15 and 20 wt% chitosan and 7.5, 10 and 15 wt% nanobioglass (nBG). Electrospinning process was performed with optimal conditions of spinning machine including voltage of 16 kV, syringe-collector spacing of 16 cm, and output rate of 1 µl per hour. The developed phases and the formation of chemical bonds between ceramic and polymer bands were studied through XRD and FTIR analyses. The FE-SEM and TEM analyses showed uniform morphology of nanofibers and dispersion of bioglass nanoparticles in the fiber structure. The presence of 10 wt% bioglass nanoparticles and 15 wt% chitosan increased the tensile strength of fibers to 3.42 MPa, which was about four times greater than strength of control sample (pure PHB). The developed fibers were kept 28 days in SBF solution and 60 days in PBS solution to assess their bioactivity and biodegradability. The results showed that the presence of bioglass nanoparticles leads to a dramatic increase in absorption of calcium and phosphorus ions and weight loss of scaffold. The developed scaffold can be used for bone and teeth tissue engineering applications. 相似文献
A new lead complex, [Pb(mq)2], (mq = 2-methyl-8-hydroxyquinoline) was prepared via an electrochemical route from the oxidation of lead metal in the presence of 2-methyl-8-hydroxyquinoline in a fast and facile process. The complex was fully characterized by means of NMR and IR spectra and elemental analysis. The nanostructure of the prepared compound was obtained by sonoelectrochemical process and studied by scanning electron microscopy, atomic force microscopy, X-ray powder diffraction, IR spectroscopy and elemental analysis. Thermal stability of single crystalline and nanosize samples of the prepared compound was studied by thermal gravimetric and differential thermal analysis. The photoluminescence properties of the prepared compounds, as single crystals and as nanorods, have been investigated. The results showed a good correlation between the size and the shape of the complex particles and emission wavelength. The prepared complex was doped in PVK:PBD blend as guest and its application in the fabrication of OLED was studied. The ratio of lead complex was modified and was equal to 8 (w/w %) in PVK:PBD (100:40). 相似文献
Effect of ZSM-5 zeolite promotion using potassium, strontium, and cerium metals on conversion of methanol to light olefins and aromatics was investigated. ZSM-5 catalyst was promoted using wet impregnation of metal salts and its activity was tested in methanol to hydrocarbons process under optimum operational condition obtained in our group previously. Zeolite samples were characterized by X-ray powder diffraction, scanning electron microscopy, N2 adsorption-desorption, acid sites distribution, and strength using temperature programmed desorption of NH3. Results showed that presence of these metals could significantly affect acid site distribution and therefore influence the catalyst activity and selectivity to olefins and aromatics. 相似文献
Mechanical properties of aluminum-silicon-copper alloys are enhanced through precipitation hardening. The response of these alloys to age-hardening is very slow. To overcome this problem, 0.2, 0.4 and 0.7 wt.% magnesium were added to Al-10.5Si-3.4Cu alloy. The new alloys were subjected to two types of precipitation hardening processes different in the solutionizing stage. The results showed that the presence of various amounts of magnesium in the composition of this alloy accelerates the response to ageing treatments, increasing the hardness and strength. Higher mechanical properties can be achieved when the alloys were subjected to a two-stage solution heat treatment. It is found that Al-10.5Si-3.4Cu alloy containing 0.2 wt.% Mg treated through a two-stage solution process, has optimum properties with ultimate tensile strength of 383.9 MPa, yield strength of 289.7 MPa and elongation of 3.97%, and can be used as a substitute for a large number of aluminum castings which need high strength and excellent castability. 相似文献