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161.
The Journal of Supercomputing - Spin-transfer torque random access memory (STT-RAM) is a suitable alternative to DRAM in the large last-level caches (L3Cs) on account of low leakage, the absence of... 相似文献
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Majid Mazouchi Mohammad Bagher Naghibi‐Sistani Seyed Kamal Hosseini Sani Farzaneh Tatari Hamidreza Modares 《International Journal of Adaptive Control and Signal Processing》2019,33(2):262-284
This paper develops a relative output‐feedback–based solution to the containment control of linear heterogeneous multiagent systems. A distributed optimal control protocol is presented for the followers to not only assure that their outputs fall into the convex hull of the leaders' output but also optimizes their transient performance. The proposed optimal solution is composed of a feedback part, depending of the followers' state, and a feed‐forward part, depending on the convex hull of the leaders' state. To comply with most real‐world applications, the feedback and feed‐forward states are assumed to be unavailable and are estimated using two distributed observers. That is, a distributed observer is designed to measure each agent's states using only its relative output measurements and the information that it receives by its neighbors. Another adaptive distributed observer is designed, which uses exchange of information between followers over a communication network to estimate the convex hull of the leaders' state. The proposed observer relaxes the restrictive requirement of having access to the complete knowledge of the leaders' dynamics by all the followers. An off‐policy reinforcement learning algorithm on an actor‐critic structure is next developed to solve the optimal containment control problem online, using relative output measurements and without requiring the leaders' dynamics. Finally, the theoretical results are verified by numerical simulations. 相似文献
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Sanae Dahbi Abdelhak Aziz Abdelhafid Messaoudi Imane Mazozi Kamal Kassmi Naima Benazzi 《International Journal of Hydrogen Energy》2018,43(10):5283-5299
In this article, the authors design a new clean storage device for a photovoltaic system (PV) reinforced by the electrical grid. The photovoltaic system supplies power to a DC load. When the power of the photovoltaic source is insufficient, the electrical grid compensates the energy deficit. On the other hand, if the load is satisfied and the PV source is still able of supplying energy, the energy excess is diverted to an own storage unit materialized by an electrolysis which produces gaseous hydrogen by the process of electrolysis of water. The authors show that the quantity of hydrogen produced is proportional to the photovoltaic energy excess and also to the flow of water injected into the electrolysis. In this case, it is a question of designing an electrolysis with specific characteristics, which takes into account the quantity of energy excess and the flow of water injected into it. The authors abandon the idea of controlling the water flow by means of a pumping-electrovalve system, and initiate the idea of replacing the function of the pump by the action of gravity. The work focuses on the development of an electrolysis optimization approach using the water flow control in its alliance with the PV power excess which is also maximized. For an optimized use of the global system (load and electrolysis), the authors present an architecture based on energy-converting structures (DC/DC and AC/DC). In addition, to increase the reliability and safety of the system, the authors finish by developing a power management strategy (PMS) in the designed system. This power management strategy organizes the energy flow and selects the appropriate path of this flow between the two energy sources (PV and electrical grid) and the two possible energy receivers (load and electrolysis). A complete modeling of the system is developed in the Matlab/Simulink environment. The simulation results show that the hybrid system (PV and electrical grid) is able to permanently supplying the load and potentially storing the excess of the PV energy in the form of hydrogen gas. 相似文献
168.
M. Aamir I. Bibi S. Ata K. Jilani F. Majid S. Kamal N. Alwadai M.A.S. Raza M. Bashir S. Iqbal M. Aadil M. Iqbal 《Ceramics International》2021,47(12):16696-16707
In the present investigation, La1-xCoxCr1-yFeyO3 (x,y = 0.0, 0.12, 0.36, 0.60) perovskite was fabricated via a facile micro-emulsion route. The synthesized perovskites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques to examine the effect of Co and Fe ions on the physico-chemical properties. The ferroelectric, dielectric, and magnetic properties of La1-xCoxCr1-yFeyO3 were changed significantly as a function of dopants contents (Co and Fe ions). Outcomes revealed that the dielectric, ferroelectric and magnetic properties of LaCrO3 perovskite can be tuned significantly via Co and Fe doping and La0.40Co0.60Cr0.40Fe0.60O3 have potential for photocatalytic dye removal under (visible) light expoure. The photocatalytic activity (PCA) of the pristine LaCrO3 and La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst was evaluated under (visible) light irradiation for crystal violet (CV) dye. Experimental results revealed that La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst degrdae almost 77.21% CV dye with the rate constant value of 0.01475 min?1. In the presence of isopropyl alcohol (IPA) scavenger, the PCA of the La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst and rate constant value of the photocatalytic reaction decreased to 32.5% and 0.00491 min?1, suggesting the superoxide as main active specie. Results revealed that Co and Fe doping doped material is efficient for photocatalytic presentations under solar light expoure. 相似文献
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Hina Kamal Cheng Foh Le Andrew M. Salter Asgar Ali 《Comprehensive Reviews in Food Science and Food Safety》2021,20(3):2455-2475
The chief intent of this review is to explain the different extraction techniques and efficiencies for the recovery of protein from food waste (FW) sources. Although FW is not a new concept, increasing concerns about chronic hunger, nutritional deficiency, food security, and sustainability have intensified attention on alternative and sustainable sources of protein for food and feed. Initiatives to extract and utilize protein from FW on a commercial scale have been undertaken, mainly in the developed countries, but they remain largely underutilized and generally suited for low-quality products. The current analysis reveals the extraction of protein from FW is a many-sided (complex) issue, and that identifies for a stronger and extensive integration of diverse extraction perspectives, focusing on nutritional quality, yield, and functionality of the isolated protein as a valued recycled ingredient. 相似文献
170.
Using black coatings and materials with high light absorbance that are capable of absorbing photons at visible and longer wavelengths is a very effective way to reduce unwanted stray light, also known as optical noise, within optical equipment. These lights can be greatly reduced to a reasonable level by functional and performable black coatings that are modified to absorb incident light as much as possible by their specific pigments. In the present work, several carbonaceous pigments were synthesized for the first time from wasteful materials and their optical properties in the visible and near‐infrared ranges studied. First, MCM‐48 and SBA‐15 were synthesized at different conditions and were then used as templates for carbonaceous products. SSS‐1 (the carbonic pigment synthesized by the mixture of sucrose and sodium silicate), SSS‐2 (the carbonic pigment synthesized by the mixture of sawdust and sodium silicate), and mesoporous carbon pigments (CMK‐3 and CMK‐1 with different levels of saturations) were synthesized. Finally, their structure, morphology, and optical properties were investigated by X‐ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE‐SEM), and Diffuse Reflectance Spectroscopy (DRS). The results indicated that the SSS‐1 pigment had a lower reflectance (below 1%) than carbon black (about 2.5%) in the visible region despite it being more cost‐effective than carbon black. The mesoporous pigments showed very high light absorbance in the visible region (about 2.5%). Compared with other black pigments, the CMK‐1 was the blackest synthesized material with a very low reflectance (about 0.05% in visible region), making it an ideal candidate as a super black pigment for reducing unwanted stray light within optical equipment. 相似文献