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1.
Mobile Networks and Applications - In the era of Internet of Things (IoT) powered by 5G technologies, Automobile Industry is headed towards a revolution. In Intelligent Transport Systems (ITS),...  相似文献   
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Given an undirected graph G with edge costs and a specified set of terminals, let the density of any subgraph be the ratio of its cost to the number of terminals it contains. If G is 2-connected, does it contain smaller 2-connected subgraphs of density comparable to that of?G? We answer this question in the affirmative by giving an algorithm to pruneG and find such subgraphs of any desired size, incurring only a logarithmic factor increase in density (plus a small additive term). We apply our pruning techniques to give algorithms for two NP-Hard problems on finding large 2-vertex-connected subgraphs of low cost; no previous approximation algorithm was known for either problem. In the k-2VC problem, we are given an undirected graph G with edge costs and an integer k; the goal is to find a minimum-cost 2-vertex-connected subgraph of G containing at least k vertices. In the Budget-2VC problem, we are given a graph G with edge costs, and a budget B; the goal is to find a 2-vertex-connected subgraph H of G with total edge cost at most B that maximizes the number of vertices in H. We describe an O(log?nlog?k) approximation for the k-2VC problem, and a bicriteria approximation for the Budget-2VC problem that gives an $O(\frac{1}{\epsilon}\log^{2} n)$ approximation, while violating the budget by a factor of at most 2+ε.  相似文献   
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As part of a continued push for high permittivity dielectrics suitable for use at elevated operating temperatures and/or large electric fields, modifications of BaTiO3 with Bi(M)O3, where M represents a net‐trivalent B‐site occupied by one or more species, have received a great deal of recent attention. Materials in this composition family exhibit weakly coupled relaxor behavior that is not only remarkably stable at high temperatures and under large electric fields, but is also quite similar across various identities of M. Moderate levels of Bi content (as much as 50 mol%) appear to be crucial to the stability of the dielectric response. In addition, the presence of significant Bi reduces the processing temperatures required for densification and increases the required oxygen content in processing atmospheres relative to traditional X7R‐type BaTiO3‐based dielectrics. Although detailed understanding of the structure–processing–property relationships in this class of materials is still in its infancy, this article reviews the current state of understanding of the mechanisms underlying the high and stable values of both relative permittivity and resistivity that are characteristic of BaTiO3‐Bi(M)O3 dielectrics as well as the processing challenges and opportunities associated with these materials.  相似文献   
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Gupta  Vidyadhar  Awasthi  Himanshi  Kumar  Nitish  Pandey  Amit Kumar  Gupta  Abhinav 《SILICON》2022,14(6):2989-2997
Silicon - This present article interprets the analytical models of central channel potential, the threshold voltage, and subthreshold current for Graded-Doped Junctionless-Gate-All-Around...  相似文献   
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Third generation γ-titanium aluminides with nominal compositions Ti–45Al–5Nb–0.2B–0.2C and Ti–45Al–10Nb–0.2B–0.2C were investigated to identify the phase transformation and their morphological stability with temperature. Electron microscopy and differential scanning calorimetry were employed for the characterization of phases and for recording the corresponding transformations, respectively. It has been inferred that the order–disorder transformation temperatures α2 → α increased with increasing Niobium (Nb), while the α-transus temperature decreases. The stability of the microstructure for both alloys with temperature were also investigated. Mass change measured for the heating rates 20 °C s−1 and 30 °C s−1 reveals that the alloy Ti–45Al–10Nb–0.2–0.2C shows stability up to 1100 °C, and the alloy Ti–45Al–5Nb–0.2B–0.2C is stable up to 900 °C. The orientation relationship between the phases indicates that with the change in shape of the α phase from lamellar to equiaxed, it deviates from the Blackburn orientation relationship.

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The flow behavior and heat transfer characteristics of conjugate heat transfer under mixed convection for a three-dimensional laminar flow in a rectangular channel with six protruding heat sources, mounted on the lower wall of the channel, have been studied numerically and experimentally. At higher temperatures, radiation plays an important role. This work reports the effect of radiation on conjugate mixed convection heat transfer. Air is taken as a cooling medium and is considered to be radiatively non-participating medium. The parameters considered for the study are positions (streamwise and spansise) of the heat sources, Reynolds number, emissivity of the heat sources, and the thermal conductivity of a printed circuit board (PCB) having constant fluid properties with the Prandtl number being 0.707. The Boussinesq approximation has been used. Commercial software ANSYS Fluent has been used for numerical analysis, and experiments have been carried out in a small-sized wind tunnel. The ranges of Reynolds number, emissivity, and thermal conductivity of PCB are 115–690 (corresponding inlet velocity of 0.25–1.5), 0–0.9, and 0.038–1.4 W/mK, respectively. Results indicate that the radiative heat transfer is significant at lower Reynolds number and lower thermal conductivity of PCB. The streamwise spacing of heat sources has larger influence compared to the spanwise spacing.  相似文献   
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This paper investigates the influence of suspension characteristics on microstructure and performance of suspensions plasma sprayed (SPS) thermal barrier coatings (TBCs). Five suspensions were produced using various suspension characteristics, namely, type of solvent and solid load content, and the resultant suspensions were utilized to deposit five different TBCs under identical processing conditions. The produced TBCs were evaluated for their performance i.e. thermal conductivity, thermal cyclic fatigue (TCF) and thermal shock (TS) lifetime. This experimental study revealed that the differences in the microstructure of SPS TBCs produced using varied suspensions resulted in a wide-ranging overall TBC performance. All TBCs exhibited thermal conductivity lower than 1 W/(m. K) except water-ethanol mixed suspension produced TBC. The TS lifetime was also affected to a large extent where 10 wt % solid loaded ethanol and 25 wt % solid loaded water suspensions produced TBCs exhibited the highest and the lowest lifetime, respectively. On the contrary, TCF lifetime was not as significantly affected as thermal conductivity and TS lifetime, and all ethanol suspensions showed marginally better TCF lifetime than water and ethanol-water mixed suspensions deposited TBCs.  相似文献   
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