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Simple generalized closed-form analytic solutions, using t-out-of-s system principle, are presented for tightly coupled multiprocessor systems employing multiplebus and crossbar interconnection networks. The system bandwidth is obtained taking into account the memory and bus interference. A single equation represents both uniform and local reference models of memory access. This expression holds for any demand pattern of memory access by the processors unlike the solutions given by others, which consider only some restricted memory access patterns. The results predicted by these models have been shown to be very close to the results of simulation studies done by others.

Let G be a k-tree such that |{v ∈ V(G): deg_G(v) = k}| = 2, n = |V(G)| ≥ 2k + 2, and the maximum degree of G is at most 2k. In this paper, we will show that such a k-tree G is isomorphic to P_n,k. In this way, we give a new characterization of k-th power (i.e. P_n,k) of paths with n vertices in terms of k-trees.

Given a hexagonal cellular network with specific demand Vector and frequency separation constraints, we introduce the concept of a critical block of the network, that leads us to an efficient channel assignment scheme for the whole network. A novel idea of partitioning the critical block into several smaller sub-networks with homogeneous demands has been introduced which provides an elegant way of assigning frequencies to the critical block. This idea of partitioning is then extended for assigning frequencies to the rest of the network. The proposed algorithm provides an optimal assignment for all well-known benchmark instances including the most difficult two. It is shown to be superior to the existing frequency assignment algorithms, reported so far, in terms of both bandwidth requirement and computation time.

The photon anticorrelation experiment is simulated with the unquantized Maxwell field by implementing realistic instrument bandwidth and signal to noise ratio. The results strongly violate an inequality believed to be satisfied by all semiclassical theories, which opens up a classical interpretation that rivals quantum optics and casts doubt on potential quantum computer applications that involve optical fields.

The computation of upper bounds of the bandwidth of graphs is mainly based on the giving of a numbering which achieves these bounds. In [9], Harper proposed such a numbering for the binary hypercube, based on the Hamming weights and binary values of the hypercube vertices.

By defining an extended Hamming weight, this numbering can lead to an equivalent proof for the d-ary de Bruijn graph. We present in this paper an approach, based on the use of the continuous domain and Laplace’s theorem for asymptotically evaluating integrals, which leads to the enumeration of the vertices of the same extended Hamming weight in the non-binary case. This result allows the computation of an upper bound of the bandwidth of the unoriented de Bruijn graph, as well as an upper bound of its vertex-bisection when both the diameter and the degree are even.

The bandwidth properties of chaotic signals generated by semiconductor lasers subject to strong chaotic optical injection (COI) are investigated numerically. The chaotic output of an injection master laser (ML) is injected into the slave laser (SL). The effects of feedback strength, injection strength and bias current on the bandwidth properties are discussed in detail. Some novel results are found, the bandwidth for SL increases with the injection strength firstly until reaches a maximum, and then decrease to approach the bandwidth of ML due to the injection-locking chaos synchronization. Large feedback strength and bias current contributes to higher maximum chaotic bandwidth in the range of injection strength. That is to say, for given parameters, optimal injection strength exists contributing to highest chaotic bandwidth, and moves to a large value for a large feedback strength and bias current, which is extremely useful for increasing the transmission rate of the optical chaotic communication system.

Despite excellent high frequency and high speed performance, current-feedback operational amplifiers (CFOAs) generally exhibit poor common-mode rejection (CMRR) properties, which limit their utility [Analogue IC design: The current–mode approach, IEE Circuits and Systems Series, Peter peregrinus, 1990]. A novel current feedback operational amplifier (CFOA) with improved performance is presented. The proposed CFOA has a new current-cell [Novel current-feedback operational amplifier Design Based on a floating circuit technique, IEE Colloquium on Analogue Signal Processing, 1998], to bias the entire circuit, which achieves an incremental output resistance twice that of the well-known "Wilson" circuit. Simulation results of this new CFOA architecture indicate that the amplifier exhibits performance characteristics superior to those obtained with an established input architecture: in particular, the CMRR (common-mode rejection ratio) is 91 dB, and the d.c. offset voltage less than 26 μV.

This paper presents a novel current mirror structure based on level shifted class-AB flipped voltage follower cell, which operates at the supply voltage of 1.2V. The level shifted class-AB flipped voltage follower cell and regulated cascode structure are used at the input and the output stages to achieve low input resistance and very high output resistance, respectively. A comparison of performance parameters of the proposed current mirror with existing structures shows that the proposed current mirror has a very less current tracking error of 0.99%, high output resistance of 18.7M$\mathrm{\Omega }$, wide bandwidth of 239.245MHz and low power dissipation of 104$\mu$W. The proposed circuit has been simulated in Cadence virtuoso analog design environment and layout of the proposed circuit has been designed in Cadence virtuoso layout XL editor using BSIM3V3 180nm CMOS technology. The post-layout simulation results have also been presented to demonstrate the effectiveness of the proposed circuit.

The natural calamity and physical malfunction in the overhead transmission line cause bad impact on the networks such as mechanical failures, power losses, reduction of line capacity, and voltage drop. These adverse impacts can be reduced by implementing proper monitoring systems. Wireless sensor network is an apt mechanism to monitor the overhead transmission network because of its physical configuration. This paper portrays the communication between wireless sensor networks and central data processing station. Cellular communication can directly transmit information through an assisted cellular module (CM) based on the probability of cellular coverage. In this paper, one of the modern optimization techniques, i.e., artificial bee colony algorithm, is used to study the problem of CM placement of cellular communication. By using this algorithm, the optimal number and location of the CMs for a test system varied from 10 to 100 are determined. A novel optimal link path scheme is proposed to check the condition of the required quality of services of both cellular/ZigBee users. The attained results show that the methodology is best suited to acquire low cost solution for the cellular module placement problem.

A new analog four-quadrant multiplier in CMOS technology is proposed using translinear loops (TLs). The novelty of the work includes an improved structure resulting in high precision output, low power consumption and low body effect error. The higher accuracy is achieved using a symmetrical arrangement of the proposed multiplier, where the errors on the two sides of circuit are subtracted from each other. The simple structure, as well as the sharing bias branch in the squaring circuits, leads to the low power dissipation of the multiplier circuit. In addition, the proposed circuit is thoroughly analyzed in terms of the body effect error and the results are presented. In order to validate the performance of the circuit, the designed multiplier is used in two useful applications: frequency doubler and amplitude modulator. The post layout simulation results of the circuit are performed using Cadence Virtuoso and HSPICE with level 49 parameters (BSIM3v3) of TSMC 0.18$\mu$m technology. The results show a nonlinearity of 0.93%, a total harmonic distortion (THD) of 0.98% at a frequency of 1MHz, a $-$3dB bandwidth of 736MHz and a maximum power dissipation of 0.0619mW.

We propose a simple and direct node shifting method with hill climbing for the well-known matrix bandwidth minimization problem. Many heuristics have been developed for this NP-complete problem including the Cuthill-McKee (CM) and the Gibbs, Poole and Stockmeyer (GPS) algorithms. Recently, heuristics such as Simulated Annealing, Tabu Search and GRASP have been used, where Tabu Search and the GRASP with Path Relinking achieved significantly better solution quality than the CM and GPS algorithms. Experimentation shows that our method achieves the best solution quality when compared with these while being much faster than newly-developed algorithms.

The optimum parameters of multiple tuned mass dampers (MTMD) for suppressing the dynamic response of a base-excited damped main system are investigated by a numerical searching technique. The criterion selected for the optimality is the minimization of the steady state displacement of the main system under harmonic base acceleration. The parameters of the MTMD that are optimized include: the damping ratio, the tuning frequency ratio and the frequency bandwidth. The optimum parameters of the MTMD system and corresponding displacement are obtained for different damping ratios of the main system and different mass ratios of the MTMD system. The explicit formulas for the optimum parameters of the MTMD (i.e. damping ratio, bandwidth and tuning frequency) are then derived using a curve-fitting scheme that can readily be used in engineering applications. The error in the proposed explicit expressions is investigated and found to be negligible. The effectiveness of the optimally designed MTMD system is also compared with that of the optimum single tuned mass damper. It is observed that the optimally designed MTMD system is more effective for vibration control than the single tuned mass damper. Further, the damping in the main system significantly influences the optimum parameters and the effectiveness of the MTMD system.

The error rate in a current-controlled logic microprocessor dominated by shot noise has been investigated. It is shown that the error rate increases very rapidly with increasing cutoff frequency. The maximum clock frequency of the processor, which works without errors, is obtained as a function of the operational current. The information channel capacity of the system is also studied.

Active Electrodes (AEs) are electrodes which have integrated bio-amplifier circuitry and are known to be less susceptible to motion artifacts and environmental interference. In this work, a low-power and high-input impedance amplifier for active electrode application is implemented based on subthreshold biasing strategies. In this proposed Application Specific Integrated Circuit (ASIC) device was versatile and numerical to achieve a high degree of programmability. It could be adapted to any other external part of one cochlear prosthesis, the sound analyzer that could be driven by a Digital Signal Processor (DSP). This research work also discusses the measurement of the electrode-skin impedance mismatch between two electrodes while concurrently measuring a bioelectrical signal without degradation of the performance of the amplifier, the efficient, noise-optimized analysis of bioelectrical signals utilizing two-wired active buffer electrodes. The reduction of power-line interference when using amplifying electrodes employing autonomous adaption of the gain of the subsequent differential amplification. The amplifier’s features include offset compensation, Common Mode Rejection Ratio (CMRR) improvement in software and a bandwidth extending down to DC. The proposed active electrode amplifier is designed using 90 nm CMOS technology. Simulation results exhibit up to the change in noise immunity and lessening in power utilization contrasted with the traditional bio-amplifier design at a similar delay.

Meshing is one of the key tasks in using the finite element method (FEM), the smoothed finite element method (S-FEM), finite volume method (FVM), and many other discrete numerical methods. Linear triangular (T3) mesh is one of the most widely used mesh, because it can be generated and refined automatically for discrete domains of complicated geometry, and hence save significantly the time for model creation. This paper presents a modified triangulation algorithm based on the advancing front technique to provide a comprehensive linear triangular mesh generator with six connectivity lists, including element–node (Ele–N) connectivity, element–edge (Ele–Eg) connectivity, edge–node (Eg–N) connectivity, edge–element (Eg–Ele) connectivity, node–edge (N–Eg) connectivity and node–element (N–Ele) connectivity. These six connectivity lists are generated along the way when the T3 elements are created, and hence it is done in a most efficient fashion. The connectivity is recorded in the usual counter-clockwise convention for convenient utilization in various S-FEM models for effective analyses. In addition, an algorithm is developed for renumbering the nodes in the T3 mesh to obtain a minimized bandwidth of stiffness matrices for both FEM and S-FEM models.

A capacitive MEMS Ultra-Low-Power readout for accelerometers and strain sensors using VerilogA models is presented. The VerilogA model of the accelerometers and strain sensors allows the simulation of a system in a half-bridge configuration. The gain of the system is controlled by integrating pulses from the excitation voltage which accurately controls the Signal-to-Noise ratio. A Figure-of-Merit of was achieved for a sensor range of ±2.0 g and ±20,000 με over a 100 Hz bandwidth. Residual motion artefacts are also canceled by the system.

The frequency spectrums are inefficiently utilized and cognitive radio has been proposed for full utilization of these spectrums. The central idea of cognitive radio is to allow the secondary user to use the spectrum concurrently with the primary user with the compulsion of minimum interference. However, designing a model with minimum interference is a challenging task. In this paper, a transmission model based on cyclic generalized polynomial codes discussed in [2] and [15], is proposed for the improvement in utilization of spectrum. The proposed model assures a non interference data transmission of the primary and secondary users. Furthermore, analytical results are presented to show that the proposed model utilizes spectrum more efficiently as compared to traditional models.