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11.
The counter current heat exchanger theory with periodic inlet temperatures has been applied to analyze the thermal performance of a water heating system. The theoretical results obtained are in agreement with the experimental data reported in the literature. 相似文献
12.
Alok Kumar Rastogi A. K. Tiwari 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(9):1825-1845
A shielded suspended dielectric guide is a dielectric rectangular slab enclosed by regular metallic side walls from all the sides. This type of structure is used in dual mode phase shifter where the size of the normal rectangular wave guide is reduced at the ends, where a dielectric material is embeded in ferrite core. Hence impedance variation of a phase shifter at its transition may be easily calculated using shielded suspended dielectric guide which is a prime parameter for optimum efficiency of wave launching. 相似文献
13.
14.
Maheshwari Rashmi Kumar Naveen Shadi Monal Tiwari Shailesh 《The Journal of supercomputing》2021,77(8):8653-8673
The Journal of Supercomputing - Data availability ensures efficient data accessibility by the readers anytime and from anywhere. It can be addressed by creating multiple copies of each data file... 相似文献
15.
Number of blends were prepared by intergrinding clinker, gypsum, fly ash, calcined clay, microsilica and limestone in laboratory ball mill in varying percentages, and their physical properties such as fineness, consistency, setting time and compressive strength have been determined. The durability tests on selected compositions were also conducted by exposing the mortar cubes separately in 5% Na2SO4 and 5% NaCl solutions till the age of 90 and 180 days. The performance was observed by compressive strength development criteria after various length of exposure. Results have been discussed and found that the durability of blended cement is higher than the ordinary Portland cement. 相似文献
16.
On the induction plasma deposition of tungsten metal 总被引:1,自引:0,他引:1
X. L. Jiang R. Tiwari F. Gitzhofer M. I. Boulos 《Journal of Thermal Spray Technology》1993,2(3):265-270
The central particle injection and long residence time characteristics of induction plasma have given rise to the complete
melting of tungsten particles injected into an Ar- H2 plasma under soft vacuum conditions. The influences of process variables such as power level, chamber pressure, and spray
distance on splat morphology, apparent density, and deposition efficiency have been studied. Dense tungsten deposits with
no oxidation have been obtained. Scanning electron microscopy (SEM) micrographs reveal a well-flattened lamellar structure
in deposits. Radiative cooling is observed to play a significant role in the plasma spraying of this refractory metal. 相似文献
17.
Qi, the wireless power standard, has been proposed to allow low power systems to receive power through wireless inductive power transfer. The standard outlines the essential, desired and optional requirements for developing the wireless power transfer platform. In this paper, we present the design and implementation results of communication controller for guided positioning single transmitter–single receiver wireless power transfer platform. Apart from the basic design, additional processing and data storage capability is introduced to make the design adaptive in terms of response time and the size of control data transfer. The method of estimating the amount of power transfer is modified to reduce design complexity and internal power consumption of power transmitter and receiver. The implementation results help to access the ratio of power transferred to resource utilization and the ratio of power transferred to power consumed in simplistic wireless power transfer platform. 相似文献
18.
Low-density parity-check (LDPC) codes have become the part of various communication standards due to their excellent error correcting performance. Existing methods require matrix inverse computation for obtaining a systematic generator matrix from parity check matrix. With the change in code rate or code length the process is repeated and hence, a large number of pre-processing computations time and resources are required. In the existing methods, the complexity of encoding is essentially quadratic with respect to the block length. In this paper, it is shown that the parity check matrix can be constructed using patterned sub-matrix structure such that the matrix inverse operation is replaced by matrix multiplication of sparse matrices. The sparseness of matrices is then utilized to obtain efficient encoders which can achieve encoding in real time with reduced pre-computation complexity. Hardware implementation of encoder and simulation results show that the proposed encoder achieves throughput in excess of 1 Gbps with the same error correcting performance as the conventional designs. 相似文献
19.
In this paper, an Adaptive Hierarchical Ant Colony Optimization (AHACO) has been proposed to resolve the traditional machine
loading problem in Flexible Manufacturing Systems (FMS). Machine loading is one of the most important issues that is interlinked
with the efficiency and utilization of FMS. The machine loading problem is formulated in order to minimize the system unbalance
and maximize the throughput, considering the job sequencing, optional machines and technological constraints. The performance
of proposed AHACO has been tested over a number of benchmark problems taken from the literature. Computational results indicate
that the proposed algorithm is more effective and produces promising results as compared to the existing solution methodologies
in the literature. The evaluation and comparison of system efficiency and system utilization justifies the supremacy of the
algorithm. Further, results obtained from the proposed algorithm have been compared with well known random search algorithm
viz. genetic algorithm, simulated annealing, artificial Immune system, simple ant colony optimization, tabu search etc. In
addition, the algorithm has been tested over a randomly generated problem set of varying complexities; the results validate
the robustness and scalability of the algorithm utilizing the concepts of ‘heuristic gap’ and ANOVA analysis. 相似文献
20.
Nikita Tiwari Raksha Pandit Swapnil Gaikwad Aniket Gade Mahendra Rai 《IET nanobiotechnology / IET》2017,11(2):205
Aim: The authors report the biological synthesis of zinc oxide nanoparticles (ZnO‐NPs) from the petals extract of Rosa indica L. (rose). Its efficacy was evaluated against two dermatophytes: namely: Trichophyton mentagrophytes and Microsporum canis which cause onychomycosis. The activity of antibiotics against the tested dermatophytes was enhanced, when evaluated in combination with ZnO‐NPs. Methods and results: The synthesised ZnO‐NPs were preliminary detected by using ultraviolet UV visible spectroscopy, which showed specific absorbance. The ZnO‐NPs were further characterised by nanoparticle tracking analysis (NTA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X‐ray diffraction and Zetasizer. Moreover, nanoparticles containing nail paint (nanopaint) was formulated and its antifungal activity was also assessed against T. mentagrophytes and M. canis. ZnO‐NPs and formulated nanopaint containing ZnO‐NPs, both showed significant antifungal activity. The maximum activity was noted against M. canis and lesser against T. mentagrophytes. Minimum inhibitory concentration of ZnO‐NPs was also determined against the dermatophytes causing onychomycosis infection. Conclusion: ZnO‐NPs can be utilised as a potential antifungal agent for the treatment of onychomycosis after more experimental trials.Inspec keywords: diseases, zinc compounds, nanoparticles, nanofabrication, antibacterial activity, microorganisms, nanomedicine, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopy, X‐ray diffraction, biomedical materials, patient treatmentOther keywords: zinc oxide nanoparticle biosynthesis, Rosa indica L petals extract, nail paint, antifungal activity evaluation, dermatophyte, Trichophyton mentagrophytes, Microsporum canis, antibiotics activity, ultraviolet‐visible spectroscopy, nanoparticle tracking analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, X‐ray diffraction, zetasizer, antifungal agent, onychomycosis treatment 相似文献