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Abstract: In this paper, we propose a new method for reversible data hiding by employing the hierarchical relationships of original images. There are many parameters for accessing the performances of reversible data hiding algorithms, including the output image quality, the hiding capacity, and the overhead for decoding. Considering the ease of implementation and the little overhead needed for decoding, we employ modification of difference values between pixels by using histogram-based scheme with extensions to pyramidal structure by utilizing inherent characteristics of original images. By doing so, global and local characteristics of original images can be utilized for hiding more capacity with acceptable quality of output image. With our method, better performances can be obtained with enhanced image quality, the more embedding capacity, and comparable amount of side information for decoding. More importantly, the reversibility of our method is guaranteed, meaning that original image and hidden message can both be perfectly recovered at the decoder. Simulation results demonstrate that proposed method in this paper outperforms those in conventional algorithms. [Copyright &y& Elsevier]

Abstract: This paper presents an effective fault location technique for transmission grids based on phasor measurement units (PMUs). High accuracy in fault location is achieved by using both the fault observability with PMUs placement and an accurate distributed parameter line model for the transmission lines. The work performed in this paper is provided with high performance which is simplicity, sensitivity, stability and featuring robustness to the uncertainties in fault inception angle, load current and fault path resistance, and the accuracy and reliability of the calculation for the technique is very high. This paper illustrates the characteristics of the proposed algorithm and evaluates its performance by using transient fault data obtained from PSCAD/EMTDC simulations. [Copyright &y& Elsevier]

Abstract: Testing algorithms with real cars is a mandatory step in developing new intelligent abilities for future transportation systems. However, this step is sometimes hard to accomplish especially due to several problems. It is also difficult to reproduce the same scenario several times. Besides, some critical and/or real world forbidden scenarios cannot be tested. Thus, the comparison of several algorithms using the same experimental conditions is hard to realize. Considering that, it seems important to use simulation tools to perform scenarios with realistic conditions. The main problem with these tools is their distance from real conditions, since they deeply simplify the reality. This paper presents the architecture of the simulation/prototyping tool named Virtual Intelligent Vehicle Urban Simulator (vivus). The goal of vivus is thus to overcome the general drawbacks of classical solutions by providing the possibility of designing a vehicle virtual prototype with simulated embedded sensors and physical properties. Experiments made on linear platoon algorithms are exposed in this paper in order to illustrate the similarities between simulated results and those obtained with real cars. [Copyright &y& Elsevier]

Abstract: The paper presents a PI tuning strategy for air handler discharge air temperature control in building comfort application. It recommends using a 5min settling time with no overshoot as the design criterion to select PI gain values, and recommends that a PI controller should be retuned when the settling time is larger than 20min. This tuning strategy avoids unnecessary tuning while providing acceptable control performance for building comfort control. The paper further concludes that PI tuning can be done by adjusting proportional gain only and keeping the reset time constant for air handler discharge air temperature control. The proportional gain can be calculated based on the system sum of time constant and delay, and system static gain in typical applications. Inclusion of the time constant in the equation is recommended for uncommon applications where the delay is large. Regression equations are given based on simulation results for both typical applications and uncommon applications. The PI tuning strategy proposed in the paper can be reliably used in PI auto tuning since it uses less model information and adjusts less gain values than existing tuning algorithms. [Copyright &y& Elsevier]

Abstract: In this paper, a simple method to find the minimum output variance (MOV) with proportional–integral-derivative (PID) controller is proposed. An assessment of improved achievable PID performance is important as PID controllers are the most commonly used in industries. The restriction on the controller structure e.g. PID (the case in this paper) results worst output variance compared to minimum variance (MV) benchmark. The problem in assessing the PID-MOV rises a non-convex problem and for non-convex problem, no direct and simple solution is possible. In this paper the non-convex problem is solved with simple ring of iterations. Several simulation examples are incorporated to show the usefulness of proposal algorithm. [Copyright &y& Elsevier]

Abstract: This paper presents a new algorithm, written in C-language for Implementation of Distributed Generation (IDG) to radial distribution feeder, heavily overloaded with non-uniformly distributed load. Majority of the existing algorithms are designed for distribution feeders with uniformly distributed load, working in single DG scenario. The applicability of these algorithms is restricted because of the unity power factor and high computational work. The methodology proposed in the research paper is capable of functioning under randomly distributed load conditions with low power factor for single DG as well as multi-DG system. The algorithm is based on analytical approach and is implemented to radial distribution network, considering the worse case scenario. The analyses carried out show that the algorithm can be applied to enhance the performance of distribution system in terms of node voltage profile improvement and power loss reduction. The simulation results indicate that IDG is capable of identifying the optimal location and size of DG in any problematic distribution system effectively. The results obtained are verified and are within the international standards limits. [ABSTRACT FROM AUTHOR]

Abstract: Voltage regulation is an important task in electrical engineering for controlling node voltages in a power network. A widely used solution for the problem of voltage regulation is based on adjusting the taps in under load tap changers (ULTCs) power transformers and, in some cases, turning on Flexible Alternating Current Transmission Systems (FACTS), synchronous machines or capacitor banks in the substations. Most papers found in the literature dealing with this problem aim to avoid voltage drops in radial networks, but few of them consider power losses or meshed networks. The aim of this paper is to present and evaluate the performance of several multi-objective algorithms, including hybrid approaches, in order to minimize both voltage deviation and power losses by operating ULTCs located in high voltage substations. In particular, a well-known multi-objective algorithm, PAES, is used for this purpose. PAES finds a set of solutions according to Pareto-optimization concepts. Furthermore, this algorithm is hybridized with simulated annealing and tabu search to improve the quality of the solutions. The implemented algorithms are evaluated using two test networks, and the numerical results are analyzed with two metrics often used in the multi-objective field. The results obtained demonstrate the good performance of these algorithms. [Copyright &y& Elsevier]

Abstract: Studying the inherently high-dimensional nature of the data in a lower dimensional manifold has become common in recent years. This is generally known as dimensionality reduction. A very interesting strategy for dimensionality reduction is what is known as subspace analysis. Beginning with the Eigenface method, face recognition and in general computer vision has witnessed a growing interest in algorithms that capitalize on this idea and an ample number of such efficient algorithms have been proposed. These algorithms mainly differ in the kind of projection method used (linear or non-linear) or in the criterion employed for classification. The objective of this paper is to provide a comprehensive performance evaluation of about twenty five different subspace algorithms under several important real time test conditions. For this purpose, we have considered the performance of these algorithms on data taken from four standard face and object databases namely ORL, Yale, FERET and the COIL-20 object database. This paper also presents some theoretical aspects of the algorithm and the analysis of the simulations carried out. [Copyright &y& Elsevier]

Abstract For process monitoring, it's of significance to pay more attention to some performance indexes related to quality, economy or security. To this end, a novel performance monitoring method based on the prediction of the performance indexes is proposed in this paper to promote the efficiency of process monitoring. In this study, firstly, the process variables are classified into two categories according to the correlation with the performance indexes. Based on the two categories of variables, a balanced Partial Least Square algorithm is proposed by constructing an enhanced objective function to predict the performance indexes which cannot be measured online. Then, the prediction residual is modeled for monitoring via the Statistics Pattern Analysis to capture the variation in the performance indexes. Finally, two Simulink examples and a practical example are utilized for illustration and validation. Highlights • BPLS-RSPA is proposed to distinguish the performance relevant or irrelevant faults and simplify the monitoring logic. • An enhanced objective function is proposed for information extraction based on the two categories of variables. [ABSTRACT FROM AUTHOR]

Geographic protocols have been recently developed for data routing in wireless ad hoc networks. These protocols are based on the exact location of each sensor node, by assuming that sensor nodes are equipped with geographic positioning services or localization-based techniques. At each node, the routing decision is based only on the position of the destination node and the position of the forwarding node’s neighbors. Location-based techniques, such DV-Hop, have attracted a lot of interest in order to estimate nodes positions. In this paper, we evaluate the performance of DV-Hop localization technique for estimating nodes localization and integrate it within the greedy perimeter stateless routing protocol. Simulations have been conducted to show the effectiveness of using localization-based techniques when integrated into geographical routing protocols for wireless sensor networks. [ABSTRACT FROM AUTHOR]

The area of projected shadow on building facades may play a role of paramount importance in the prediction of solar energy conversion and building thermal and energy performance. Algorithms for solar shading calculations may directly affect the accuracy of results obtained by building energy simulation tools. In addition, the consideration of uncertain design parameters imply an estimative of a confidence interval of solar fraction results that determine the reliability as well as the improvement of shading calculation models. In this way, this paper presents a methodology for uncertainty and sensitivity analysis applied to the prediction of sunlit area on building exterior surfaces with shading devices. From a single building model, the solar fraction was investigated for two cities and four typical days. According to the obtained results, more than 20% of all simulation time steps have uncertainties equal or higher than 5% on the solar fraction calculation at 95% confidence level. The maximum values of the uncertainties occur in warmer months, which could significantly impact the building energy balance. Three inputs have higher influence on the uncertainties on solar fraction results: (1) latitude, (2) orientation and (3) width of overhang fins. Perturbation of only 5° on the building orientation may imply important uncertainties on solar fraction, which is normally neglected by designers. The results highlight the importance of assessing the uncertainty of inputs in algorithms such as the one to calculate the surface solar fraction that is an important prerequisite of the final building energy balance. [ABSTRACT FROM AUTHOR]

Ns-3 simulator provides a great platform for experimental studies on different communication technologies and network topologies, and it is already used by many researchers all around the world. Unfortunately, its current TCP implementation is outdated and not ready for being used as reference platform for TCP-centered research, relegating ns-3 to play a background role in favor of its predecessor, ns-2. This paper presents the update process of ns-3 TCP module, that offers to TCP developers and researchers a consistent and RFC-compliant platform to base their works on. The method involves the addition of a new congestion-based state machine, the split of congestion control out from the socket core, and the development of a very detailed and complete testing framework, which can be easily extended. Performance tests follow the description, comparing RAM usage and execution time between ns-3 releases. Also, a case study over high-delay links on the interaction between the Transmission Control Protocol (TCP) and CoDel, an Active Queue Management algorithm born to control queuing delay, is presented. [ABSTRACT FROM AUTHOR]

Abstract: The bin-normalized frequency-domain block LMS (FBLMS) algorithm has low computational burden and potential fast convergence; however, it suffers from a biased steady-state solution when the reference signal lags behind the desired signal or the adaptive filter is of insufficient length. This paper proposes a unified framework for the FBLMS algorithm, which can be used to comprehensively analyze its steady-state behavior. Furthermore, a modified FBLMS algorithm with guaranteed optimal steady-state performance is proposed based on the framework. Simulations are carried out to demonstrate the benefit of the proposed algorithm. [Copyright &y& Elsevier]

Abstract: This paper presents a new maximum power point tracking method based on the current–voltage characteristic of photovoltaic arrays. The new approach is not only capable to track the maximum power point like the conventional methods under uniform insolation conditions, but also capable to find the global maximum power point efficiently and rapidly under partially shaded conditions. The proposed algorithm could find a new MPP quickly when a sudden change occurs in the insolation level. To verify the performance of the proposed method, several simulations have been carried out in MATLAB/Simulink environment. Experimental investigations have also been performed to confirm the validity of simulation results. [Copyright &y& Elsevier]

Abstract: In this paper an efficient Medium Term Conflict Detection and Resolution (MTCD&R) approach based on 4D trajectories to solve conflicts in a Terminal Maneuvering Area (TMA) is presented. The conflict detection subsystem (CD) is based on a Spatial Data Structure (SDS), avoiding non-efficient pairwise trajectory comparisons, and using a simplified wake vortex modeling through 4D tubes to detect time-based separation infringements between aircraft. The conflict resolution subsystem (CR) solves the detected conflicts with an efficient and dynamic 3D allocation of the arrival routes that takes into consideration the execution of Continuous Descent Approaches (CDAs). Algorithms have been tested with several stressing traffic scenarios (rush hour and saturation rush hour) taking place in a 3D simulation model of Gran Canaria Extended TMA. The resulting conflict-free trajectories have been validated for flyability conformance both with real A380 FMS avionics and with a certified B738 Full Flight Simulator. A new CR performance metric to measure the degree of runway utilization is also proposed in order to enable comparisons between different MTCD&R systems. Finally, a discussion about strengths and limitations of the algorithms for reducing controller’s workload while increasing airspace capacity of the future Single European Sky is outlined. [Copyright &y& Elsevier]

Abstract: In this paper, an improved novel joint channel estimation algorithm is proposed for the 112Gbit/s PDM CO-OFDM system. This method combines the advantages of the intra-symbol frequency domain averaging (ISFA) method and the time domain averaging (TA) method, which can realize more accuracy channel estimation. Simulation results show that this proposal could promise a relatively stable performance even under a rapidly time varying environment. It significantly outperforms the ISFA method by 2.2dB when the DGD equals 1000ps, and has the advantages of 0.5dB over ISFA in considering the laser linewidth and frequency offset. [Copyright &y& Elsevier]

Abstract: In this paper, we propose an efficient simulation-based two-stage scheduling methodology by integrating vector ordinal optimization (VOO) and response surface methodology (RSM) to make a good scheduling policy for fab operation. The suggested method combines local and global rules into a single rule, with the objective of simultaneously optimizing multiple performance indices. Our approach consists of 2 stages: rule combination selection, and parameter optimization. In the first stage, we apply the VOO techniques to effectively selecting good rule combination. Results show that 1 orders of computation time reduction over traditional simulations can be achieved. In the second stage, we adopt RSM and desirability function to tune the parameters associated to scheduling algorithm. The proposed approach is validated by means of a comparison with other scheduling policies. The results show that the proposed scheduling method is effective. [Copyright &y& Elsevier]

Abstract: Contour tracking is one of the most common control problems encountered by many industrial manipulators and robots to achieve high precision contour performance. In this paper, a new contour tracking control method developed in position domain is proposed aiming at improving the contour tracking performance. To develop the new control algorithm, a multi-axis motion system is treated as a master–slave cooperative motion system; the master motion is sampled equidistantly and used as a reference, while the slave motions are expressed as functions of the master motion according to desired contour requirements. A dynamic model of the multi-axis motion system represented in position domain is developed based on the master motion through one to one mapping from time domain to position domain. A PD type position domain control is proposed, and the stability analysis is conducted based on the Lyapunov function method. The developed position domain control is applied to contour tracking of linear motion and circular motion, and some comparison studies are performed between time domain control and position domain control. Simulation results demonstrate the effectiveness of the position PD control compared with traditional PD control and the crossed-coupled control. [Copyright &y& Elsevier]

Abstract: This paper proposes a repeated blind source separation (BSS) method based on morphological filtering and singular value decomposition (SVD) to separate the mixed sources from a single-channel signal. Firstly the signal is de-noised by the morphological filter and, the noise which affects the accuracy of the separation is removed. Next, the purified signal is reconstructed in phase space, and the SVD is applied to this matrix. After choosing the effective singular values, the inverse transform is applied to the revised signal matrix. From this, the pseudo signal can be obtained. The pseudo signal and the purified original signal are used to achieve the mixed sources separation through the fast independent component analysis (FastICA) algorithm. Then, the methods above are repeated in order to separate the weaker signals. The analysis of simulation and practical application demonstrates that that proposed method shows a high level of separating performance of a single-channel signal. [Copyright &y& Elsevier]

Abstract: This paper proposes a bit-level image encryption algorithm based on spatiotemporal chaotic system which is self-adaptive. We use a bit-level encryption scheme to reduce the volume of data during encryption and decryption in order to reduce the execution time. We also use the adaptive encryption scheme to make the ciphered image dependent on the plain image to improve performance. Simulation results show that the performance and security of the proposed encryption algorithm can encrypt plaintext effectively and resist various typical attacks. [Copyright &y& Elsevier]

Abstract: In this paper, the problem of initial alignment for Inertial Navigation System (INS) is discussed. Based on the Lyapunov transformation, INS error model of stationary base is established. Then, the initial alignment for INS can be transformed into the robust filter design problem for linear systems with multiple disturbances. A robust multi-objective filter is constructed for the concerned INS with disturbance rejection and attenuation performance, where the drift estimations are applied to reject the inertial sensor drifts and mixed filter is adopted to attenuate Gaussian noises and norm bounded disturbances. Finally, simulations for stationary base alignment of an Inertial Navigation System are given to show the efficiency of the proposed approach. [Copyright &y& Elsevier]

Abstract: The Backoff Algorithm is the heart of Medium Access Control(MAC) protocol which determines the system throughput in IEEE802.11 networks. Due to the nature of Wireless medium, stations are not immediately allowed to transmit data as they have data to send. Backoff algorithm has to take an important and crucial decision to correctly predict the precious waiting time for the station before accessing the medium. Hence deigning an effective and efficient Backoff algorithm is required for Wireless Networks. This paper discusses, simulates and analyzes the various Backoff Algorithms and compares the results obtained using NS2 simulator. [Copyright &y& Elsevier]

Abstract: One-sided dense matrix factorizations are important computational kernels in many scientific and engineering simulations. In this paper, we propose two extensions of both right-looking (LU and QR) and left-looking (Cholesky) one-sided factorization algorithms to utilize the computing power of current heterogeneous architectures. We first describe a new class of non-GPU-resident algorithms that factorize only a submatrix of a coefficient matrix on a GPU at a time. We then extend the algorithms to use multiple GPUs attached to a multicore. These extensions not only enable the factorization of a matrix that does not fit in the aggregated memory of the multiple GPUs at once, but also provide potential of fully utilizing the computing power of the architectures. Since data movement is expensive on the current architectures, these algorithms are designed to minimize the data movement at multiple levels. To demonstrate the effectiveness of these algorithms, we present their performance on a single compute node of the Keeneland system, which consists of twelve Intel Xeon processors and three NVIDIA GPUs. The performance results show both negligible overheads and scalable performance of our non-GPU-resident and multi-GPU algorithms, respectively. These extensions are now parts of the MAGMA software package, a set of the state-of-the-art dense linear algebra routines for a multicore with GPUs. [Copyright &y& Elsevier]

Abstract: In this paper, comparative performance analysis of various binary coded PSO algorithms on optimal PI and PID controller design for multiple inputs multiple outputs (MIMO) process is stated. Four algorithms such as modified particle swarm optimization (MPSO), discrete binary PSO (DBPSO), modified discrete binary PSO (MBPSO) and probability based binary PSO (PBPSO) are independently realized using MATLAB. The MIMO process of binary distillation column plant, described by Wood and Berry, with and without a decoupler having two inputs and two outputs is considered. Simulations are carried out to minimize two objective functions, that is, time integral of absolute error (ITAE) and integral of absolute error (IAE) with single stopping criterion for each algorithm called maximum number of fitness evaluations. The simulation experiments are repeated 20 times with each algorithm in each case. The performance measures for comparison of various algorithms such as mean fitness, variance of fitness, and best fitness are computed. The transient performance indicators and computation time are also recorded. The inferences are made based on analysis of statistical data obtained from 20 trials of each algorithm and after having comparison with some recently reported results about same MIMO controller design employing real coded genetic algorithm (RGA) with SBX and multi-crossover approaches, covariance matrix adaptation evolution strategy (CMAES), differential evolution (DE), modified continuous PSO (MPSO) and biggest log modulus tuning (BLT). On the basis of simulation results PBPSO is identified as a comparatively better method in terms of its simplicity, consistency, search and computational efficiency. [Copyright &y& Elsevier]

Abstract: Sparse linear arrays provide better performance than the filled linear arrays in terms of direction estimation and resolution with reduced size and low cost. However, they are subject to manifold ambiguity. A method based on the Multiple Signal Classification (MUSIC) algorithm to solve the manifold ambiguity of uncorrelated sources for sparse array is proposed in this paper. The method consists of two steps. The first step is to obtain all the directions of arrivals (DOAs), including true and spurious DOAs, using traditional MUSIC. The second step is to estimate the power values of the all DOAs by substituting all the DOAs to a cost function. The well-known Davidson Fletcher Powell (DFP) and Broyden Fletcher Goldfarb Shanno (BFGS) algorithms are used to estimate the power values. The power values of spurious DOAs are very small or tend to zero compared with the values of the true DOAs. The true DOAs are then discriminated easily from the spurious DOAs with the power values. Simulation results demonstrate the effectiveness and the feasibility of the method. [Copyright &y& Elsevier]

Abstract: In this paper, the design of decentralized PID controller for interactive and delay time processes is proposed. Direct controller synthesis approach is used to obtain parameters of the multi-loop controllers. A detuning factor for each loop is specified based on the closed-loop time constant. Then appropriate controller settings are determined using the Maclaurin series expansion and the model of the process. The success of the proposed algorithm is based on the detuning parameter thus the selection of the desired closed-loop time constant is an important factor. The proposed method has no limitations regarding systems weak or strong interactions, multiple delays, and its operating behaviors such as monotonic or oscillatory. The proposed algorithm is simpler and improved performance of various processes are achieved as compared to some of the prevalent techniques. Simulation examples demonstrate the usefulness of the proposed method. [Copyright &y& Elsevier]

Abstract: To solve the increasing problem of Inter-cell interference in LTE, put forward an algorithm based on technologies of SRS sounding and Adaptive Modulation and Coding which is proved, in this paper, to be adequately achieve the goal of Inter-cell interference coordination/avoidance. Simulation and analyzing of the algorithm have indicated that it could effectively improve the performance of the subscribers located at the edge of the cells in a certain degree. [Copyright &y& Elsevier]

Abstract: A background modeling scheme in compressed sensing (CS) imaging system is proposed in this paper, in which background evaluation is performed on the measurement vectors directly before reconstruction. The estimated background measurement vector is constructed through average, running average, median and block-based selective method respectively. Then the estimated background image is reconstructed using the background model measurements through the gradient projection for sparse reconstruction (GPSR) algorithm. The simulations show that the proposed background modeling algorithms in CS scheme provide promising results. [Copyright &y& Elsevier]

Abstract: Orthogonal frequency division multiplexing (OFDM) suffers from a high peak-to-average power ratio (PAPR).Tone reservation is a popular PAPR reduction technique that uses a set of reserved tones to design a peak-canceling signal. In this paper, the performance and complexity of clipping noise guided, complex base-band active-set methods based on tone reservation for PAPR reduction are analyzed and simulated. The simulation results show that the two clipping noise guided methods, the adaptive scale method and constant scale method, have better performance than complex base-band active-set methods. Furthermore, the complexity of the constant scale algorithm is lower than the adaptive scale and the complex base-band active-set algorithm. [Copyright &y& Elsevier]

Abstract: Active Constellation Extension (ACE) is one of the techniques introduced for Peak to Average Power Ratio (PAPR) reduction of OFDM systems. In this technique, the constellation points are extended such that the PAPR is minimized but the minimum distance of the constellation points does not decrease. In this paper, an iterative ACE method is proposed for the PAPR reduction of OFDM systems with spatial diversity of Space Frequency Block Coding (SFBC). The proposed method is such that the PAPR is reduced simultaneously at all antennas, while the spatial encoding relationship still holds. In this method, at each iteration, the antenna with maximum PAPR is selected and the ACE algorithm is applied; then the signal of the other antennas are constructed from the resultant signal using SFBC relationship. Simulation results show that the algorithm converges and its performance is very close to the performance of the ACE in single antenna systems and it outperforms the alternative methods for PAPR reduction of SFBC–OFDM systems when the number of subcarriers increases. [Copyright &y& Elsevier]

Abstract: The paper proposes two modulation techniques for the power inverter. These new techniques are named progressive decrement PWM algorithm (PDPA) and progressive increment PWM algorithm (PIPA). Both techniques take the determined original pulse-width of an inverter operation and split it to many pulses. In the PDPA technique, the largest width is given to the middle pulse and the width of the boundary pulses is reduced progressively starting from the first boundary-pulse toward the last boundary-pulse. In the PIPA technique, there is a gradual increment instead of decrement. The two techniques have been proved that it can maintain the original pulse-width of the inverter operation. The new approach PDPA extends the central pulse and shrinks the exterior pulses, leading to an inverter output cycle close to the sinusoidal form of fewer harmonic contents. Simulation results are performed to evaluate the performances of the proposed techniques: PDPA and PIPA and to compare them with the well known methods. The main contribution of the proposed PDPA technique is that it provides a better performance for the most harmonic orders compared to the well established sinusoidal PWM technique. [Copyright &y& Elsevier]

Abstract: Comprehensive two-dimensional gas chromatography (GC×GC) is a powerful technology for separating complex samples. The typical goal of GC×GC peak detection is to aggregate data points of analyte peaks based on their retention times and intensities. Two techniques commonly used for two-dimensional peak detection are the two-step algorithm and the watershed algorithm. A recent study compared the performance of the two-step and watershed algorithms for GC×GC data with retention-time shifts in the second-column separations. In that analysis, the peak retention-time shifts were corrected while applying the two-step algorithm but the watershed algorithm was applied without shift correction. The results indicated that the watershed algorithm has a higher probability of erroneously splitting a single two-dimensional peak than the two-step approach. This paper reconsiders the analysis by comparing peak-detection performance for resolved peaks after correcting retention-time shifts for both the two-step and watershed algorithms. Simulations with wide-ranging conditions indicate that when shift correction is employed with both algorithms, the watershed algorithm detects resolved peaks with greater accuracy than the two-step method. [Copyright &y& Elsevier]

Abstract: This paper discusses the communication and control co-design and co-simulation of wireless networked control systems. The interactions between the network and the control system are considered, and general networking and control co-design solutions are proposed for wireless control applications. The PiccSIM simulator for wireless control system simulation is used to study the effects of specific network protocol and control algorithms in practice. Packet loss models based on measurements of real industrial radio environments are incorporated into the simulator. This allows the realistic evaluation of the suitability of the network protocols for wireless control applications. A network quality of service measure is introduced, which gives a direct relationship between the network and control performances. Two simulation cases show the capabilities of PiccSIM for wireless control application research and development, where the co-design issues and solutions are demonstrated in detail. [Copyright &y& Elsevier]

Abstract: This paper investigates the misplacement issue presented on the detection of feature points by using the well-known Harris detector, under several watermarking attacks. Harris detector, as a powerful tool in finding image''s points of high importance, called “interest points”, has been widely used to locate specific image portions where watermarks are embedded, according to some watermarking insertion procedure. Although Harris detector constitutes a significant part of a typical feature-based watermarking process, no work dealing with its performance under certain attacks has been reported yet. This work studies the accuracy of Harris detector in finding the feature points, which define the watermarked regions of attacked images, firstly as an individual processing module and secondly as a part of a feature-based watermarking methodology. Detailed theoretical analysis followed by appropriate simulation experiments has shown that the incorporation of the Harris detector into the watermarking procedure presents misplacement issues that can lead the watermarking algorithm to unreliable results. In the way of decreasing these misplacement errors, a novel algorithm that extracts more stable interest points, with promising performance is also proposed. [Copyright &y& Elsevier]

Abstract: In this paper dynamic routing and wavelength assignment strategies have been proposed for multiclass WDM optical networks. Multiclass optical networks provide multiple classes of services to the subscriber according to the requirement, which in turn increase operational profitability. Each class of service could be characterized by parameters like number of wavelengths, expected call holding time and average arrival rate of request. The proposed strategies have been analyzed and compared with existing strategies on the basis of blocking probabilities for multiclass traffic scenarios. Simulation results on different network topologies demonstrate that the performance of proposed strategies “Fixed shortest/alternate shortest path routing with wavelength reservation (FSASWR)” and “Fixed alternate shortest path routing with least priority wavelength assignment (FASPL)” are much better as compared to existing strategies. Proposed strategies minimize blocking probability of the multiclass network using limited number of wavelengths. [Copyright &y& Elsevier]

Abstract: In this paper, a closed-loop fuzzy logic controller based on the particle swarm optimization algorithm is proposed for controlling the power level of nuclear research reactors. The principle of the fuzzy logic controller is based on the rules constructed from numerical experiments made by means of a computer code for the core dynamics calculation and from human operator''s experience and knowledge. In addition to these intuitive and experimental design efforts, consequent parts of the fuzzy rules are optimally (or near optimally) determined using the particle swarm optimization algorithm. The contribution of the proposed algorithm to a reactor control system is investigated in details. The performance of the controller is also tested with numerical simulations in numerous operating conditions from various initial power levels to desired power levels, as well as under disturbance. It is shown that the proposed control system performs satisfactorily under almost all operating conditions, even in the case of very small initial power levels. [Copyright &y& Elsevier]

Abstract: In this paper, we focus on the semi-partitioned scheduling of sporadic tasks with constrained deadlines and identical processors. We study two cases of semi-partitioning: (i) the case where the worst case execution time (WCET) of a job can be portioned, each portion being executed on a dedicated processor, according to a static pattern of migration; (ii) the case where the jobs of a task are released on a processor, 1 time out of p, where p is an integer at most equal to the number of processors, according to a round-robin migration pattern. The first approach has been investigated in the state-of-the-art by migrating a job at its local deadline, computed from the deadline of the task it belongs to. We study several local deadline assignment heuristics (fair, based on processor utilization and based on the minimum acceptable local deadline for a job on a processor). In both cases, we propose feasibility conditions for the schedulability of sporadic tasks scheduled using earliest deadline first (EDF) semi-partitioned scheduling. We show that the load function used for global scheduling to establish the feasibility of sporadic task sets exhibits interesting properties in the semi-partitioning context. We carry out simulations to study the performance of the two approaches in terms of success rate and number of migrations, for platforms composed of four and eight processors. We compare the performance of these semi-partitioned heuristics with the performance of classical partitioned scheduling algorithms and with a global scheduling heuristic which is currently considered to have good performances. [Copyright &y& Elsevier]

Abstract: This paper describes a torque ripple reduction technique with constant switching frequency for direct torque control (DTC) of an induction motor (IM). This method enables a minimum torque ripple control. In order to obtain a constant switching frequency and hence a torque ripple reduction, we propose a control technique for IM. It consists of controlling directly the electromagnetic torque by using a modulated hysteresis controller. The design methodology is based on space vector modulation (SVM) of electrical machines with digital vector control. MATLAB simulations supported with experimental study are used. The simulation and experimental results of this proposed algorithm show an adequate dynamic to IM; however, the research can be extended to include synchronous motors as well. The implementation of the proposed algorithm is described. It doesn’t require any PI controller in the torque control loop. The hardware inverter is controlled digitally using a Texas Instruments TMS320F240 digital signal processor (DSP) with composed C codes for generating the required references. The results obtained from simulation and experiments confirmed the feasibility of the proposed strategy compared to the conventional one. [Copyright &y& Elsevier]

Abstract: This paper describes INSEE, a simulation framework developed at the University of the Basque Country. INSEE is designed to carry out performance-related studies of interconnection networks. It is composed of two main modules: a Functional Simulator of Interconnection Networks (FSIN) and a TRaffic GENeration module (TrGen), together with several other modules that extend INSEE’s functionality. The router models and topologies implemented in FSIN are included in this description. Likewise, the available methods to generate traffic are described thoroughly. Finally, the resource consumption of INSEE when managing different systems and workloads is also evaluated. INSEE has been used to conduct a variety of studies, including evaluation of novel topologies, diagnosis of causes of network congestion and evaluation of parallel scheduling algorithms. [ABSTRACT FROM AUTHOR]

Abstract: The most crucial aspect of distributed real-time systems is the scheduling algorithm, which must guarantee that every job in the system will meet its deadline. In this paper, we evaluate by simulation the performance of strategies for the dynamic scheduling of composite jobs in a heterogeneous distributed real-time system. Each job that arrives in the system is a directed acyclic graph of component tasks and has an end-to-end deadline. For each scheduling policy, we provide alternative versions which allow the insertion of tasks into idle time slots, using various bin packing techniques. The comparison study, based on different workloads and system heterogeneity levels, shows that the alternative versions of the algorithms outperform their respective counterparts. [ABSTRACT FROM AUTHOR]

Abstract: This paper explores scheduling a realistic variant of open shops with parallel machines per working stage. Since real production floors seldom employ a single machine for each operation, the regular open shop problem is very often in practice extended with a set of parallel machines at each stage. The purpose of duplicating machines in parallel is to either eliminate or to reduce the impact of bottleneck stages on the overall shop efficiency. The objective is to find the sequence which minimizes total completion times of jobs. We first formulate the problem as an effective mixed integer linear programming model, and then we employ memetic algorithms to solve the problem. We employ Taguchi method to evaluate the effects of different operators and parameters on the performance of memetic algorithm. To further enhance the memetic algorithm, we hybridize it with a simple form of simulated annealing as its local search engine. To assess the performance of the model and algorithms, we establish two computational experiments. The first one is small-sized instances by which the model and general performance of the algorithms are evaluated. The second one consists of large-sized instances by which we further evaluate the algorithms. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents novel store-and-forward packet routing algorithms for Wireless Body Area Networks (WBAN) with frequent postural partitioning. A prototype WBAN has been constructed for experimentally characterizing on-body topology disconnections in the presence of ultra short range radio links, unpredictable RF attenuation, and human postural mobility. On-body DTN routing protocols are then developed using a stochastic link cost formulation, capturing multi-scale topological localities in human postural movements. Performance of the proposed protocols are evaluated experimentally and via simulation, and are compared with a number of existing single-copy DTN routing protocols and an on-body packet flooding mechanism that serves as a performance benchmark with delay lower-bound. It is shown that via multi-scale modeling of the spatio-temporal locality of on-body link disconnection patterns, the proposed algorithms can provide better routing performance compared to a number of existing probabilistic, opportunistic, and utility-based DTN routing protocols in the literature. [Copyright &y& Elsevier]

Abstract: Use of deep sub-micron VLSI technologies in fabrication of Network on Chips (NoCs) makes the reliability to be one of the first order concerns in the design of these products. This paper proposes and evaluates a methodology that adds reliability to NoC routing algorithms with minimal power and performance overheads. The key idea behind this methodology is to use the concept of complement routing in which two routing algorithms with disjoint sets of allowed turns are incorporated. According to this methodology, while a packet is routed by a routing algorithm, a redundant copy of that packet is routed by the complement of that routing algorithm. This is done by exploiting channels with lower utilization to route redundant packets. To find the complement of the used NoC routing algorithm, an analytical approach based on the channel dependency graph is presented. The methodology is applied to two NoCs using the dimension order and the Duato’s routing algorithms. These networks are simulated using an HDL-based NoC simulator along with the Synopsys Power Compiler tool. Results extracted by different traffic generation rates and by different error injection rates confirm that the proposed methodology provides similar reliability improvement in comparison with the flood-based routing algorithms. This methodology also decreases the performance and power consumption overheads as compared to the flood-based routing algorithms. [Copyright &y& Elsevier]

Abstract: In this study, a mathematical model is described and developed based on a set of algebraic equations which is capable of artificially generating normal events of the electrocardiogram (ECG) such as P-wave, QRS complex, T-wave or synthetic abnormal phenomena like ST-segment episodes (i.e. depression, elevation, and sloped ascending or descending) and repolarization abnormalities such as T-wave alternans (TWA). In order to demonstrate the flexibility of the presented model for the simulation of various ECG signals, fascicular ventricular tachycardia, rate dependent conduction block, and acute Q-wave infarctions of inferior and anterior-lateral walls are simulated. Then, using the proposed artificial ECG signal, two new developed QRS detection algorithms (Modified Hilbert transform-MHT and discrete wavelet curve length-DWCL algorithms) evolved, respectively based on the implementation of some modifications to the conventional Hilbert and discrete wavelet transforms of the ECG signal, are then evaluated. To meet this end, a mathematically-simulated ECG signal with a weak R-wave is embedded into a Gaussian noise with a wide range for variances (powers) and the MHT and DWCL algorithms are applied to the resulted signal to detect QRS complexes. In the next step, an artificial baseline wander is added to the ECG signal and the performance of the MHT and DWCL algorithms in cases of high baseline wander are studied. After conducting numerous simulations, it was concluded that for the values of signal to noise ratio (SNR) larger than −5dB and amplitudes of baseline wanders approximately less than 5 times of R-wave amplitude, the two detection algorithms will have acceptable performance while it is seen that in low (negative) SNR values, performance endurance of the DWCL based detection algorithm is higher than MHT method. The Matlab m-file script of the synthetic ECG generator will be freely available from the Appendix of this paper. [Copyright &y& Elsevier]

Abstract: In this paper, we present an efficient external calibration technique for a typical multi-camera system. The technique is very handy in practice using a simple planar pattern. Based on homography, three different pair-wise estimation algorithms are proposed to recover the rigid rotation and translation between neighboring cameras. By registering the accurate and reliable partial calibrated structures, the complete calibration of a multi-camera system can be accomplished. In order to evaluate and compare the calibration results for different camera setups, a novel accuracy metric is introduced based on the deflection angles of projection rays. Experimental results using both simulated and real data are presented to verify the validity and performance of the proposed method. [Copyright &y& Elsevier]

Abstract: In this paper we present a general formalism for the establishment and mean-square performance analysis of the family of selective partial update affine projection (SPU-AP), selective regressor affine projection (SR-AP), and selective partial update subband adaptive filter (SPU-SAF) algorithms. This analysis is based on energy conservation arguments and does not need to assume a Gaussian or white distribution for the regressors. We demonstrate through simulations that the results are useful in predicting the performance of these adaptive filter algorithms. [Copyright &y& Elsevier]

Abstract: Based on the baseline PI control structure, the control parameters of non-linear ALSTOM gasifier benchmark problem are optimized. Firstly, taking all the input and output limits under three load conditions as constraints, the relative IAE indices at six scenarios are calculated and optimized by using multi-objective optimization algorithm NSGA-II. A set of non-dominated solutions are obtained which facilitate the further improvement on the performance under coal quality change. Then among those non-dominated solutions, the solution with best coal quality flexibility comes to the fore through a selection procedure. The simulation results show that the optimization and selection procedure presented in this paper improves the baseline PI control performance with better dynamic responses and coal quality flexibility. [Copyright &y& Elsevier]

Abstract: In this paper biomechanical interaction between osseointegrated dental implants and bone is numerically investigated through 3D linearly elastic finite-element analyses, when static functional loads occur. Influence of some mechanical and geometrical parameters on bone stress distribution is highlighted and risk indicators relevant to critical overloading of bone are introduced. Insertions both in mandibular and maxillary molar segments are analyzed, taking into account different crestal bone loss configurations. Stress-based performances of five commercially-available dental implants are evaluated, demonstrating as the optimal choice of an endosseous implant is strongly affected by a number of shape parameters as well as by anatomy and mechanical properties of the site of placement. Moreover, effectiveness of some double-implant devices is addressed. The first one is relevant to a partially edentulous arch restoration, whereas other applications regard single-tooth restorations based on non-conventional endosteal mini-implants. Starting from computer tomography images and real devices, numerical models have been generated through a parametric algorithm based on a fully 3D approach. Furthermore, effectiveness and accuracy of finite-element simulations have been validated by means of a detailed convergence analysis. [Copyright &y& Elsevier]