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1.
Journal of Materials Science: Materials in Electronics - The Co1?xZnxFe2O4 (Co–Zn) ferrite nanoparticles with x varying from 0.0 to 0.4 have been manufactured by facile chemical...  相似文献   
2.
Journal of Materials Science: Materials in Electronics - Herein, we report the synthesis of three-dimensional (3D) and one-dimensional (1D) hierarchical hematite (α-Fe2O3) nanostructures on...  相似文献   
3.

In this paper, we propose to use Artificial Bee Colony (ABC) optimization to solve the joint mode selection, channel assignment, and power allocation (JMSCPA) problem to maximize system throughput and spectral efficiency. JMSCPA is a problem where the allocation of channel and power depends on the mode selection. Such problems require two step solution and are called bi-level optimization problems. As bi-level optimization increases the complexity and computational time, we propose a modified version of single-level ABC algorithm aided with the adaptive transmission mode selection algorithm to allocate the cellular, reuse, and dedicated modes to the DUs along with channel and power allocation based on the network traffic load scenarios. A single variable, represented by the users (CUs and DUs) is used to allocate mode selection, and channel allocation to solve the JMSCPA problem, leading to a simpler solution with faster convergence, and significant reduction in the computational complexity which scales linearly with the number of users. Further, the proposed solution avoids premature stagnation of conventional ABC into local minima by incorporating a modification in its update procedure. The efficacy of the ABC-aided approach, as compared to the results reported in the literature, is validated by extensive numerical investigations under different simulation scenarios.

  相似文献   
4.
Novel lead-free (1-x)Ba0·9Ca0·1Ti0·9Zr0·1O3-xSrNb2O6 ceramics were synthesized via a two-step high energy ball milling process. The evolution of microstructural properties, phase transformation, and energy storage characteristics was comprehensively investigated to assess the applicability of material in multi-layered ceramic capacitors. The substitution of SrNb2O6 (SNO) in Ba0·9Ca0·1Ti0·9Zr0·1O3 (BTCZ) has resulted in substantial improvement in materials density along with a small increase in the grain size of the synthesized ceramic. A thorough microstructural investigation indicates an excellent dispersibility and compatibility between BTCZ and SNO phases. With an increase in SNO substitution, a transition from typical ferroelectric to relaxor ferroelectric has been observed, which has led to a significantly slimmer ferroelectric loop along with frequency dispersive dielectric properties. The optimized composition (i.e., x = 0.10) exhibits an ultra-high recoverable energy density of 2.68 J/cm3 along with a moderately high energy efficiency of 83.4%. Further, SNO substituted samples have also shown an enhancement in breakdown strength. The improvement in energy storage performance and breakdown strength of SNO substituted BTCZ composites are mainly attributed to relatively homogeneous grain morphology, optimum grain size, microstructural density, and improved grain boundary interface.  相似文献   
5.
Multimedia Tools and Applications - The automatic binary classification of normal and abnormal subjects using magnetic resonance (MR) brain images has made remarkable progress in recent years. This...  相似文献   
6.
Wireless Personal Communications - A relatively new area of research and development is Swarm Robotics. It is a part of the swarm intelligence field. In the proposed paper, we shall use swarm...  相似文献   
7.
Wireless Personal Communications - Effect of combination of dual split ring resonator and electromagnetic bandgap structures over substrate integrated waveguide and half-mode substrate integrated...  相似文献   
8.
This paper proposes a novel hybrid technique called enhanced grey wolf optimization-sine cosine algorithm-cuckoo search (EGWO-SCA-CS) algorithm to improve the electrical power system stability. The proposed method comprises of a popular grey wolf optimization (GWO) in an enhanced and hybrid form. It embraces the well-balanced exploration and exploitation using the cuckoo search (CS) algorithm and enhanced search capability through the sine cosine algorithm (SCA) to elude the stuck to the local optima. The proposed technique is validated with the 23 benchmark functions and compared with state-of-the-art methods. The benchmark functions consist of unimodal, multimodal function from which the best suitability of the proposed technique can be identified. The robustness analysis also presented with the proposed method through boxplot, and a detailed statistical analysis is performed for a set of 30 individual runs. From the inferences gathered from the benchmark functions, the proposed technique is applied to the stability problem of a power system, which is heavily stressed with the nonlinear variation of the load and thereby operating conditions. The dynamics of power system components have been considered for the mathematical model of a multimachine system, and multiobjective function has been framed in tuning the optimal controller parameters. The effectiveness of the proposed algorithm has been assessed by considering two case studies, namely, (i) the optimal controller parameter tuning, and (ii) the coordination of oscillation damping devices in the power system stability enhancement. In the first case study, the power system stabilizer (PSS) is considered as a controller, and a self-clearing three-phase fault is considered as the system uncertainty. In contrast, static synchronous compensator (STATCOM) and PSS are considered as controllers to be coordinated, and perturbation in the system states as uncertainty in the second case study.  相似文献   
9.
Microsystem Technologies - This paper reports the development of a novel electronic micro-viscometer capable of measuring viscosity of different Newtonian fluids using less than 100 µl which...  相似文献   
10.
A model cancer cell line was used to initiate polymerisation of pyrrole to form the conducting material polypyrrole. The polymerisation was shown to occur through the action of cytosolic exudates rather than that of the membrane redox sites that normally control the oxidation state of iron as ferricyanide or ferrocyanide. The data demonstrate for the first time that mammalian cells can be used to initiate synthesis of conducting polymers and suggest a possible route to detection of cell damage and/or transcellular processes through in situ and amplifiable signal generation.  相似文献   
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