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41.
Two novel low-power 1-bit Full Adder cells are proposed in this paper. Both of them are based on majority-not gates, which are designed with new methods in each cell. The first cell is only composed of input capacitors and CMOS inverters, and the second one also takes advantage of a high-performance CMOS bridge circuit. These kinds of designs enjoy low power consumption, a high degree of regularity, and simplicity. Low power consumption is targeted in implementation of our designs. Eight state-of-the-art 1-bit Full Adders and two proposed Full Adders are simulated using 0.18 μm CMOS technology at many supply voltages. Simulation results demonstrate improvement in terms of power consumption and power-delay product (PDP).  相似文献   
42.
到了45纳米技术节点,高介电常数绝缘材料和金属栅电极将被用于射造逻辑电路器件。而采用高金属功函数和能隙工程电荷陷阱的闪存也能从这些项技术中获益。  相似文献   
43.
Computational error due to the fixed-point implementation of two-dimensional (2-D) discrete wavelet transform (DWT) is analyzed. This analysis is based on the exact knowledge of the DWT analysis and synthesis filters and the word length of the original image. In the fixed-point implementation, it is crucial to understand and analyze effects of finite precision in filters coefficients as well as rounding of intermediate calculations for the purpose of storage and/or transmission. Analyses and formulations are presented for both convolution and lifting approaches and they are validated by Monte Carlo simulations. The specific example used throughout this work is the lossy wavelet transformation used in the JPEG2000 compression standard.  相似文献   
44.
The hybrid algorithm for real-time vertical handover using different objective functions has been presented to find the optimal network to connect with a good quality of service in accordance with the user’s preferences. Markov processes are widely used in performance modelling of wireless and mobile communication systems. We address the problem of optimal wireless network selection during vertical handover, based on the received information, by embedding the decision problem in a Markov decision process (MDP) with genetic algorithm (GA), we use GA to find a set of optimal decisions that ensures the best trade-off between QoS based on their priority level. Then, we emerge improved genetic algorithm (IGA) with simulated annealing (SA) as leading methods for search and optimization problems in heterogeneous wireless networks. We formulate the vertical handoff decision problem as a MDP, with the objectives of maximizing the expected total reward and minimizing average number of handoffs. A reward function is constructed to assess the QoS during each connection, and the AHP method are applied in an iterative way, by which we can work out a stationary deterministic handoff decision policy. As it is, the characteristics of the current mobile devices recommend using fast and efficient algorithms to provide solutions near to real-time. These constraints have moved us to develop intelligent algorithm that avoid the slow and massive computations. This paper compares the formulation and results of five recent optimization algorithms: artificial bee colony, GA, differential evolution, particle swarm optimization and hybrid of (GA–SA). Simulation results indicated that choosing the SA rules would minimize the cost function, and also that, the IGA–SA algorithm could decrease the number of unnecessary handovers, and thereby prevent the ‘Ping-Pong’ effect.  相似文献   
45.
Personalization is a key aspect of biophysical models in order to impact clinical practice. In this paper, we propose a personalization method of electromechanical models of the heart from cine-MR images based on the adjoint method. After estimation of electrophysiological parameters, the cardiac motion is estimated based on a proactive electromechanical model. Then cardiac contractilities on two or three regions are estimated by minimizing the discrepancy between measured and simulation motion. Evaluation of the method on three patients with infarcted or dilated myocardium is provided.  相似文献   
46.
Testing for small-delay defects (SDDs) has become necessary as technology further scales. Existing tools and methodologies for generating SDD patterns suffer from: limited long-paths sensitization capability, overwhelming pattern volume, time-consuming pattern generation process, and vague evaluations of pattern quality. Such situation places patterns in a dilemma where the generation and application effort are huge yet the results cannot reflect the physical phenomena clearly enough for correct binning and diagnosis. In this paper, we focus on establishing a pattern generation flow that produces patterns of high application value. Firstly, critical faults are identified in order to generate high-quality original pattern repository with n-detect ATPG.A novelpattern evaluation and selection method that further minimizes pattern count while maintaining the SDD detection ability is then presented. Top-off ATPG is then performed to ensure meeting the target fault coverage. Along with the flow, multiple evaluation metrics are also proposed to measure the pattern’s efficiency on SDD coverage, unique SDD detection, detectable SDD size, long path distribution, etc. Experimental results demonstrate that the proposed critical fault-based method improves long path sensitization efficiency by 2.5× without impairing its average delay and saves approximately 80 % CPU runtime compared with total fault-based method. Comparing with timing-aware ATPG, the generated pattern set detects equivalent or even more SDDs with significantly reduced pattern count.  相似文献   
47.
48.
Wireless Networks - Radio over free space optics (Ro-FSO) systems have previously relied on the signal intensity, wavelength and polarization for multiplexing data streams in...  相似文献   
49.
Journal of Materials Science: Materials in Electronics - Triboelectric nanogenerators (TENGs) have marked their applications in various fields, most importantly, in medical devices. The electrical...  相似文献   
50.
The fracture toughness and deformation mechanism of PP/CaCO3 (15 wt.%) composites were studied and related to load-bearing capacity of the particles. To alter the load-bearing capacity of the particles, different particle sizes (0.07–7 μm) with or without stearic acid coating were incorporated. The fracture toughness of the composites was determined using J-Integral method and the deformation mechanism was studied by transmission optical microscopy of the crack tip damage zone. It was observed that the load-bearing capacity of the particles decreased by reduction of particle size and application of coating. A linear relationship between normalized fracture toughness and inverse of load-bearing capacity of particles was found. The crack tip damage zone in composites, which consists in massive crazing, further grows by reduction in load-bearing capacity.  相似文献   
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