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21.
Social media has become a significant part of daily life and nowadays it has started to turn out to be common practice for consumers and companies to employ social media to form, establish, and connect relationships. In addition, social media is based on web and mobile-based technologies for creating highly interactive paradigms by which communities and individuals co-create, share, modify and discuss user-generated content. However, it is never easy for businesses to create social media advertising that attracts people and encourages them to buy their products. This article intends to present a statistical analysis that focuses on social media marketing among people of different ages. Six categories—personal profile, usage, assessment, higher-order data, trustworthiness, and elements of social media ads—are included in the analysis of social media marketing. The initial phase focuses on questionnaire preparation depending on social media advertising. Subsequently, the planned questionnaire is collected from diverse respondents at various educational levels utilizing a Google form. Then, these respondents' responses are collected for examination. To determine whether the outcomes of the experiment are meaningful, the evaluation in this piece of study is based on an ANOVA analysis.  相似文献   
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Functionally graded metal matrix composites (MMCs) and homogenous composites (Al/AlN and Al/SiO2-10 wt%) have been fabricated through centrifugal casting and liquid metallurgy route, respectively. The properties of these composites were compared with aluminum alloy. Microstructural characteristics and hardness were studied on the surfaces of functionally graded materials (FGMs), homogenous composites, and unreinforced aluminum alloy using an optical microscope and a Vickers micro hardness tester, respectively. Tensile test was carried out on the outer and inner sections of FGMs and specimens from homogenous composites and alloy utilizing universal testing machines (UTMs). Three-body abrasive wear test was conducted for different loads and speeds to study their effect on the surfaces of composites and alloy using dry abrasion tester. Microstructural and hardness results reveal that the outer surface of aluminum nitride (AlN)-reinforced FGM has a particle-enriched region with the highest hardness. Tensile strength was found higher in both homogenous composites compared to zones of their FGMs. Abrasion wear rate was found increased with increase in load and decreased with increase in speed. The outer surface of AlN-reinforced FGM has higher wear resistance followed by the outer surface of SiO2-reinforced FGM. Scanning Electron Microscopy (SEM) analysis was performed on worn-out surfaces and observed particle-enriched outer surface of Al/AlN FGM with less abrasion.  相似文献   
24.
Adsorption cryocoolers are among the possible options for obtaining cryogenic temperatures, in particular for small cooling capacity applications such as cooling of infra red detectors. They need to be optimized for liquid yield. The performance of thermal compressors therein pivots around the adsorption characteristics of the adsorbent + adsorbate combination and how effectively one could pack requisite amounts of adsorbent into a given volume of the compressor housing. In addition, the overall performance of the cooler is a function of limits of operating temperatures and pressures across the compressor. This paper proposes a performance indicator—the product of liquid yield and the uptake efficiency of the compressor—and evaluates its values for various possible operating conditions for one specimen of activated carbon. It is shown that there is a limited domain of operation and that there is a condition of best performance within that domain.  相似文献   
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Mantle cell lymphoma is a rare form of B‐cell lymphoma. We present a 54‐year‐old gentleman with mantle cell lymphoma. It was diagnosed based on the demonstration of B‐cell antigens CD20 and CD5. It was further confirmed by demonstration of overexpression of cyclin D1 on these atypical lymphocytes in the immunohistochemical staining. He also had acute renal failure and proteinuria. Renal biopsy revealed crescents and lymphomatous infiltration of tubulointerstitium. The presence of infiltrating cells with similar markers in both the lymph node and the kidney confirmed the infiltration of kidney with lymphomatous cells. Our present patient, after a thorough literature search, is found to be the second one with a glomerular lesion and tubulointerstitial infiltration by malignant lymphoma cells.  相似文献   
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Centrifugal casting was adopted for fabricating AlSi5Cu3/10 wt% SiC functionally graded metal matrix composite under three different centrifugal speeds of 800, 1000 and 1200 rpm, and hollow cylindrical components (φout 150 × φin 132 × 150 mm) were obtained. Microstructures of outer and inner periphery of all composites were observed through optical microscope and micro hardness of outer, intermediate and inner region of composite was tested using Vicker’s hardness tester. Results revealed that outer region of the composites centrifuged at all speeds have particle rich region with higher hardness. Abrasive wear experiments were conducted only on surface of particle rich region based on Taguchi’s technique by varying parameters such as centrifugal speed of casting process, rotating speed and applied load of abrasive wear tester. Analysis of variance results revealed that, centrifugal speed had highest significance on wear rate. Abraded surfaces were examined using scanning electron microscope and the maximum wear resistance was observed on particle rich zone of composite centrifuged at 1200 rpm.  相似文献   
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Radhika  M.  Sivakumar  P. 《Wireless Networks》2021,27(1):27-40

This article presents the design, analyses and implementation of the novel routing protocol for energy optimization based on LEACH for WSN. Network Lifetime is the major problem in various routing protocols used in WSN. In order to overcome that problem, our proposed routing protocol is developed, which is a combination of Micro Genetic algorithm with LEACH protocol. Our proposed µGA-LEACH protocol, strengthen the cluster head (CH) selection and also reduce the energy consumption of the network when compared to existing protocols. This paper shows the improvement of network lifetime and energy consumption with the optimal CH selection based on a micro genetic algorithm and also compared the results with an existing hierarchical routing protocol like LEACH, LEACH-C, LEACH GA and GADA LEACH routing protocol with various packet sizes, and initial energy.

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28.
Neural Processing Letters - In this article, the problem of stochastic Cohen–Grossberg Bidirectional Associative Memory (CGBAM) neural networks with probabilistic time-varying delay is...  相似文献   
29.
BACKGROUND: In this work, the solid‐liquid extraction of terbium from phosphoric acid solutions using solvent‐impregnated resin containing TOPS 99, an equivalent of di‐2‐ethylhexyl phosphoric acid, has been investigated. The parameters studied include equilibration time, acid concentration, amount of resin, metal concentration, kinetics, temperature, loading, elution, regeneration and recycling. RESULTS: FT‐IR results confirm the physical interaction of the extractant with the resin. The extraction of terbium with TOPS 99 impregnated Amberlite XAD 4 resin was acid dependent and transfer of metal follows a cation exchange mechanism. The loading capacity of TOPS 99‐impregnated resin for terbium was calculated to be 23.8 mg g?1 resin. Controlling mechanism of the adsorption was found to be a chemical reaction following pseudo‐second‐order kinetics. The endothermic nature of extraction was confirmed by temperature studies. Among the various eluants studied, H2SO4 was the best. Regeneration and recycling of the resin indicated the resin can be used for continuous cycles. CONCLUSIONS: Terbium was successfully extracted from phosphoric acid using TOPS 99 extractant impregnated into Amberlite XAD4 with a maximum loading of 23.8 mg g?1 resin and fully recovered with 1 mol L?1sulfuric acid. The resin was subjected to seven cycles of extraction and elution without any loss of performance. Further studies showed that terbium could be separated from lutetium. Copyright © 2010 Society of Chemical Industry  相似文献   
30.
Treating African trypanosomiasis : The synthesis and biological evaluation of novel 1‐alkyloxy and 1‐benzyloxyadamantano 2‐guanylhydrazones, their 1‐dioxa congeners and two 1‐benzyladamantano 2‐guanylhydrazones is reported. Preliminary structure–activity relationship data were elucidated and lead compounds suitable for further optimization were discovered.

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