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141.
Zhenxing Han Manoj Kumar Ram Rajeev Kamal Turki Alamro D. Yogi Goswami Chand Jotshi 《国际能源研究杂志》2019,43(8):3732-3745
This paper aims to study the effect on the characteristics of molten salt because of the dispersion of different size nanoparticles of Al2O3. The eutectic mixture of 54 wt% KNO3 and 46 wt% NaNO3 was selected as the base salt. Five different size nanoparticles of Al2O3, 80, 135, 200, 300, and 1000 nm, were dispersed into the base salt at a mass concentration of 1% to make the nanomaterials by a two‐step method, respectively. Thermal properties of the base salt and the samples with Al2O3 nanoparticles, including the melting point temperature, fusion heat, specific heat capacity, and thermal diffusivity, were measured with differential scanning calorimeter (DSC) and Xenon Flash Apparatus (XFA). On the basis of the measured specific heat capacities and thermal diffusivities, their thermal conductivities in the solid state were calculated at discrete specified temperatures. The results showed that the dispersions of 200‐ and 135‐nm Al2O3 nanoparticles could enhance the average solid and liquid specific heat capacities by up to 17.2% and 19.7%, respectively. The research on thermal diffusivity and thermal conductivity also verified that the influences of different size nanoparticles were different. Although no new strong intensity peaks or peak position variations were found in the diffraction patterns of the two samples with 80‐ and 1000‐nm nanoparticles of Al2O3, the larger deviations in the lower wavenumber region still meant possible crystalline structure variation because of the dispersion of Al2O3 nanoparticles. Scanning electronic microscope (SEM) images showed the inhomogeneity and the agglomeration of dispersed nanoparticles in the base salt, and the formation of a nanolayer around the nanoparticles could be a possible explanation to the thermal‐physical property variation. 相似文献
142.
Silicon - Dry sliding wear characteristics, mechanical properties and microstructural behavior of powder-chip based reinforcement silicon rich LM6 aluminum alloy, fabricated by semi-solid casting... 相似文献
143.
Asif Irshad Khan Abdullah Saad Al-Malaise ALGhamdi Fawaz Jaber Alsolami Yoosef B. Abushark Abdulmohsen Almalawi Abdullah Marish Ali Alka Agrawal Rajeev Kumar Raees Ahmad Khan 《计算机、材料和连续体(英文)》2022,70(2):2835-2848
The blockchain technology plays a significant role in the present era of information technology. In the last few years, this technology has been used effectively in several domains. It has already made significant differences in human life, as well as is intended to have noticeable impact in many other domains in the forthcoming years. The rapid growth in blockchain technology has created numerous new possibilities for use, especially for healthcare applications. The digital healthcare services require highly effective security methodologies that can integrate data security with the available management strategies. To test and understand this goal of security management in Saudi Arabian perspective, the authors performed a numerical analysis and simulation through a multi criteria decision making approach in this study. The authors adopted the fuzzy Analytical Hierarchy Process (AHP) for evaluating the effectiveness and then applied the fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) technique to simulate the validation of results. For eliciting highly corroborative and conclusive results, the study referred to a real time project of diabetes patients’ management application of Kingdom of Saudi Arabia (KSA). The results discussed in this paper are scientifically proven and validated through various analysis approaches. Hence the present study can be a credible basis for other similar endeavours being undertaken in the domain of blockchain research. 相似文献
144.
The Journal of Supercomputing - Quantum dot cellular automata (QCA)-based demultiplexer or DeMUX is a basic module of nanocommunication and nanocomputation, like a multiplexer. However, the design... 相似文献
145.
Multimedia Systems - Human activity recognition has been a significant goal of computer vision since its inception and has developed considerably in the last years. Recent approaches to this... 相似文献
146.
We demonstrate an in-line fiber-optic polarizer using resonant tunneling through a leaky multilayer overlay for the first time. Polarization extinction ratio (PER) ? 27 dB with an insertion loss (IL) ? 3 dB has been demonstrated experimentally with scope of further improvement. A simple planar waveguide model is developed to analyze the device whose predictions match very well with the experimental results. It is further shown that by properly selecting the device parameters one can achieve PER ? 68 dB with IL ? 0.2 dB for λ = 0.6328 μm and PER ? 80 dB with IL ? 1.2 dB for λ = 1.3 μm. 相似文献
147.
Clustering objective reasons scalability, fault tolerance, data aggregation or fusion, load balancing of cluster heads, stabilized network topology, maximal network lifetime, increased connectivity, reduced routing delay, collision avoidance and utilizing sleeping schemes in wireless sensor networks. Load balanced clustering effectively organize the network into a connected hierarchy. Clustering is a discrete problem that can have more than one solution under different operating constraints. In this scenario, meta-heuristic algorithms are found suitable because they give set of solutions in acceptable time constraints. In the literature, several analytical and meta-heuristic approaches have been developed for load balanced clustering. In this paper, a novel harmony search based energy efficient load balanced clustering algorithm is presented and it is tested on a large sample network. Results demonstrated that the proposed approach has faster convergence and gives reliable and efficient load balanced clustering as compared to conventional harmony search algorithm (HSA) and several other methods in the literature. Moreover, the robustness of the proposed approach is also verified for different cases of fixed and variable parameters of HSA. 相似文献
148.
Bohannon Philip Lieuwen Daniel Rastogi Rajeev Silberschatz Avi Seshadri S. Sudarshan S. 《Multimedia Tools and Applications》1997,4(2):115-151
Performance needs of many database applicationsdictate that the entire database be stored in main memory.The dali system is a main memory storage manager designed toprovide the persistence, availability and safety guarantees one typically expects from a disk-resident database, while at the same time providing very high performance by virtue of being tuned to support in-memory data.User processes map the entire database into their address space andaccess data directly, thus avoiding expensive remote procedure calls andbuffer manager interactionstypical of accesses in disk-resident commercial systems available today.dali recovers the database to a consistent state in the case of system as well as process failures. It alsoprovides unique concurrency control and memory protection features, aswell as ordered and unordered index structures. Both object-oriented and relational database management systems have beenimplemented on top of dali. dali provides access to multiple layers ofapplication programming interface, including its low-level recovery,concurrency control and indexing components as well as its high-levelrelational component. Finally, various features of dali can be tailored tothe needs of an application to achieve high performance–for example,concurrency control and logging can be turned off if not desired, enablingdali to efficiently support applications that requirenon-persistent memory-resident data to be shared by multiple processes. 相似文献
149.
Manish Sharma Rajeev Kumar Preet Kaur Vigneswaran Dhasarathan Truong Khang Nguyen 《国际射频与微波计算机辅助工程杂志》2022,32(1):e22928
In this reported work, two dual notched bands from 3.39 GHz to 3.92 GHz and from 4.43 GHz to 5.48 GHz for the WiMAX band (3.3–3.8 GHz) and for (lower) WLAN band (5.15–5.35 GHz) MIMO antenna with adjacent/orthogonal orientations has been investigated. Also, the proposed antenna is capable of controlling these notched bands whenever the need for power saving arises by reconfiguring them using PIN diodes. The issue of isolation between the radiating elements has been overcome by placing the radiating structures in the adjacent and orthogonal arrangement. The proposed antenna is characterized proving an average gain of 4.15/4.37 dBi and maximum radiation efficiency of 91/87% for adjacent/orthogonal orientation. The proposed antenna also shows good agreement with simulated and measured impedance bandwidth, diversity performances in terms of ECC, DG, TARC, and CCL for which values are well below the permissible range. 相似文献
150.
Multimedia Tools and Applications - In this paper, we propose a new enhanced absolute moment block truncation coding (AMBTC) image compression method based on interpolation. The proposed... 相似文献