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Unmanned aerial vehicles (UAV) assisted edge computing has risen as an assuring technique to accommodate ubiquitous edge computation for resource‐limited devices. Thus, this paper proposes an approach to maximize the latency fairness in a UAV‐assisted multi‐access edge computing (MEC) system. To maximize latency fairness, the authors focus on minimizing the maximum latency experienced among the users. In here, multiple ground users (GUs) offload their tasks to MEC UAV in the absence or unavailability of ground servers due to a disaster or heavy traffic where an iterative algorithm is proposed to minimize the maximum latency among the users subject to minimum control link rate and total power constraints. Sequentially, the UAVs' 3D location, offloading ratio, GUs' transmit power and GUs' computational capacity are optimized. The location of the UAV is optimized by using the novel approach, guided pattern search algorithm while the altitude of the UAV is optimized by analyzing the elevation angle dependant behaviour of the channel gain. A simple approach is utilized for optimizing the offloading ratio of the users by considering the problem as minimizing the point‐wise maximum of two convex functions while the bisection method is used to optimize the power allocation. Numerical simulation results illustrate that the proposed approach outperforms other baseline approaches in convergence, minimizing the maximum latency and maximizing and maintaining the fairness among the GUs. Furthermore, it is proved that the guided pattern search algorithm converges at least 3.5 times better while the proposed combined optimization gives 400% fairness gain, in comparison with the baseline approach. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the modified minimal variance control (MMVC) of discrete-time first-order linear critically stable stochastic systems with prospective strong intervention (PSI) and control input constraints. Due to different evolutionary characteristics of systems with PSI, that is, the two modes of tending to infinity and having bounded oscillations, the discrete-time first-order linear critically stable systems can be partitioned into two types regarding the signs of a key system parameter a. A necessary and sufficient condition for the state mean convergence of a system with a = 1 is derived and the corresponding design of MMVC is formulated. For the critical stable system with a =− 1, its oscillation amplitudes of state means can be effectively suppressed or the means can converge under control. Finally, the effectiveness and advantages of the proposed control strategies comparing with MVC are confirmed by numerical simulations. [ABSTRACT FROM AUTHOR]

ABSTRACT Cloud radio access networks (C-RANs) are promising technological paradigms to improve capacity and extend coverage. However, the severe interference resulting from high density deployment of remote radio heads (RRHs) prevents to achieve high spectrum efficiency. How to mitigate the interference is a key challenging work. This paper investigates the cooperative interference management among RRHs in C-RANs. By forming coalitions and performing non-coherent joint transmission within a coalition, the intra-coalition interference among RRHs can be successfully suppressed. Considering that RRHs are selfish and rational, in this paper, the cooperation of RRHs is formulated as a coalition formation game scheme, where the necessary conditions for an RRH to cooperate are derived. To find the solution for the proposed game, an enhanced concept of defection order is proposed, based on which a self-optimal coalition formation algorithm is proposed. The performances of the proposed algorithm, in terms of convergence, complexity and fairness, are analysed as well. Simulation results show that our proposed algorithm yields significant improvements of system performance compared with both the non-cooperative scheme and the conventional broadcasting-based coalitional scheme.Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Mobile cloud computing (MCC) has been introduced with the intuition to ascertain the computing requirements of resource constraint smart mobile devices (SMDs). Meanwhile, the research community has put forward a wide variety of solutions by independently considering the operational issues of cloud service user (CSU) side (e.g., when to offload) and cloud service provider (CSP) side (e.g., where to deploy the cloud data centers). As the MCC will evolve, the decision regarding the adoption of a solution at one end would likely rely on the features supported or required from the other side; for example, a CSU might decide to offload the execution of delay‐sensitive applications only if the CSP deploys the cloud data centers in his/her proximity. The identification and convergence of such dependencies are vital for flourishing the MCC. However, a cognitive representation of CSU and CSP side research proposals can only aid in the identification of such dependencies. In this paper, we develop a thematic taxonomy of the current CSU side as well as CSP side frameworks. Further, we review the current CSU side and CSP side frameworks by using the thematic taxonomy and analyze the implications as well as critical aspects of proposed solutions. We also outline the potential dependencies between the solutions of both sides. These dependencies are derived on the basis of elicited taxonomy. Finally, we put forward open research challenges that demand future efforts for the seamless integration of CSU side perspectives and CSP side perspectives. [ABSTRACT FROM AUTHOR]

In this paper, we propose a heterogeneous cellular network based on orthogonal frequency division multiple access consisting of full-duplex femtorelays. Then, we design schemes for the uplink radio resource allocation. The goal of the proposed schemes is to maximize the sum rate, taking into account the back-haul and transmission power constraints. Moreover, the superiority of the proposed system is shown by comparing it with the half-duplex femtorelay-assisted counterpart. Since the proposed resource allocation optimization problem is nonconvex and intractable, we divide it into subcarrier and transmission power allocation subproblems and then use an iterative algorithm to solve each of them. Toward this end, in each iteration, subcarriers are allocated via a binary linear program, while the successive convex approximation method is adapted to transform the nonconvex transmission power allocation subproblem into a sequence of convex subproblems. To achieve this goal, we use 1 of the 3 proposed approaches, namely, dual, arithmetic-geometric mean approximation, and difference of 2 concave functions. In addition, we investigate the performance, convergence, and computational complexity of these approaches. The simulation results reveal that the proposed approaches are close to the optimal solution while providing less computational complexity. Moreover, they illustrate that even by considering self-interference in the full-duplex mode, the sum rate will be increased approximately by 41 % in comparison with the half-duplex mode. [ABSTRACT FROM AUTHOR]

Bernard and Jones (1996) have previously argued that similarity in the technologies used by firms in the service sector helps to explain evidence of absolute convergence at the cross-country level. This paper searches for convergence at the firm level using data for the UK service sector over the period 1988–1998. Initial mixed support for this view is partly explained by strong business cycle effects in the data. Upon closer examination we find evidence that convergence was more likely in industries that had high levels of technology investment, greater exposure to new technologies and high levels of absorptive capacity. [ABSTRACT FROM AUTHOR]

Synchronisation of radar systems can be used to suppress interference and enable communication between radars. In this paper, a generalised Kuramoto model is proposed, which can be used to synchronise pulse repetition frequencies of two radars over‐the‐air. The generalised approach allows the adjustment of a sampling factor which influences the convergence of the two pulse repetition frequencies. Furthermore, sampling criteria are derived, which can be used to estimate whether convergence occurs. Finally, it is shown by means of simulation that the model together with the criteria allows to reliably predict convergence and to perform synchronisation. [ABSTRACT FROM AUTHOR]

As the current Internet architecture is suffering from scalability issues, the network research community has proposed alternative designs for the Internet architecture. Among those solutions that adopt the idea of locator/identifier split paradigm, the locator/identifier separation protocol (LISP) has been considered as the most promising solution because of its incrementally deployable feature. Despite various advantages provided by LISP, many ISPs are still conservative to adopt LISP into their production network because the standard LISP does not fully satisfy ISP's requirements on LISP-enabled services. In this paper, we define ISP's requirements on LISP-enabled commercial services and describe limitations of the standard LISP from an ISP's perspective. Also, we propose LISP controller, a centralized LISP management system. By using LISP controller, we evaluate three ISP's representative LISP use cases: traffic engineering, virtual machine live migration, and vertical handover. The results show that the proposed LISP controller provides centralized management, controllability, and fast map entry update, without any modifications on the standard LISP. LISP controller allows an ISP to control and manage its LISP-enabled services while satisfying ISP's requirements. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The wavelet transform is a practical method for multiresolution analysis. Previously, methods for describing the transformed signal using zero-crossing information and additional complementing information (zero-crossing representation) have been studied. The zero-crossing representation, however, presents problems in that the physical interpretation of the applied additional information is not clear, and reconstruction of the original signal from the zero-crossing representation involves iterations of nonlinear operations. Other problems include the fact that extension to the multidimensional case is difficult and that the computational complexity is considerable. In this paper, the authors propose a new zero-crossing representation that uses the additional information with clear physical interpretation and has a form that is easy to handle in signal processing. A method is proposed to reconstruct the original signal from the zero-crossing representation. The method uses iterative linear operations with a theoretical guarantee of convergence and has lower computional complexity than the conventional method. The proposed zero-crossing representation is extended to the two-dimensional case and is applied to an actual image. It is experimentally verified that the reconstructed image is a good approximation to the original signal. Furthermore, the amount of additional information in the zero-crossing representation is reduced. The quality degradation of the reconstructed image is examined. © 1998 Scripta Technica, Electron Comm Jpn Pt 3, 82(1): 68–78, 1999 [ABSTRACT FROM AUTHOR]

This paper proposes a universal information source code (improved ZL code) based in the Ziv-Lempel (ZL) incremental parsing algorithm. It is known that a ZL code is asymptotically optimum for a stationary ergodic information source, although it does not utilize the source structure. Its convergence, however, is very slow and it cannot provide efficient compression for an input string of limited length. This paper considers the redundancy of ZL code, high is the reason for the slow convergence. In order to eliminate the redundancy coding scheme is presented in which only the substring obtained by incremental parsing is used in the next stage. When the substrings of the incremental parsing are separately coded the improved ZL code obtained by the proposed scheme is the least redundant in the sense that the mean code length for the substrings is minimized. In the coding a data structure called modified ZL tree is introduced and its properties discussed together with two coding algorithms based on that structure. The coding is actually performed for the output string from a memoryless binary source and binary Markov source. It is shown that sufficient compression is realized for a binary code string length of 10³ to 104, indicating the possibility as a practical data compression algorithm. [ABSTRACT FROM AUTHOR]

SUMMARY The problem of group consensus is investigated in this paper, where all agents possess double-integrator dynamics. Two different kinds of consensus protocols are proposed for networks with fixed communication topology to reach group consensus for the agents' positions and velocities. Convergence analysis is discussed, and necessary and/or sufficient conditions are presented for multiagent systems to achieve group consensus. The first protocol leads to dynamic consensus where positions of all agents reach time-varying consensus values. By applying the second protocol, both the agents' positions and their velocities reach constant consensus values. That is, static consensus is achieved. Simulation examples are given to show the effectiveness of the theoretical results.Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A hierarchical convergence mechanism for the heterogeneous wireless communication system via the heterogeneous cooperative relay node is presented in this paper, in which the techniques of cooperative communication and wireless relay are utilized to improve performances of the individual user and the overall converged networks. In order to evaluate the benefits of the proposal, a utility-based capacity optimization framework for achieving the heterogeneous cooperative diversity gain is proposed. The heterogeneous cooperative capacity, relay selection and power allocation theoretical models are derived individually. The joint optimization model for relay selection and power allocation is presented as well. Owing to the computation complexity, the sub-optimal cooperative relay selection algorithm, the sub-optimal power allocation algorithm and the sub-optimal joint algorithm are determined to approach the maximum overall networks' spectrum efficiency. These proposed algorithms are designed in conformance to guarantee the equivalent transmission rates of the different wireless access networks. The simulation results demonstrate that the utility-based capacity model is available for the heterogeneous cooperative wireless communication system, and the proposed algorithms can improve performances by achieving the cooperative gain and taking full advantage of the cross-layer design. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The design of very large learning systems presents many unsolved challenges. Consider, for instance, a system that ‘watches’ television for a few weeks and learns to enumerate the objects present in these images. Most current learning algorithms do not scale well enough to handle such massive quantities of data. Experience suggests that the stochastic learning algorithms are best suited to such tasks. This is at first surprising because stochastic learning algorithms optimize the training error rather slowly. Our paper reconsiders the convergence speed in terms of how fast a learning algorithm optimizes the testing error. This reformulation shows the superiority of the well designed stochastic learning algorithm. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Development of advanced grid‐synchronization technique for unbalanced and distorted grid is considered in this paper. In this context, self‐tuning filter (STF) is considered to extract the fundamental component from the measured unbalanced and distorted voltages. Standard STF considers balanced grid voltages which is not always possible to ensure in the actual power grid. To mitigate this issue, an extended STF is proposed by analyzing the standard STF in the state‐space framework. To make the proposed ESTF grid‐following, a robust open‐loop frequency estimator is also applied. The closed‐loop system enjoys excellent filtering benefit from the extended STF side while taking advantage of the fast convergence speed property of the open‐loop frequency estimation technique. Numerical simulation and experimental results with double second‐order generalized integrator phase‐locked loop are provided to validate the theoretical developments. [ABSTRACT FROM AUTHOR]

In this paper, the convergence properties of the method of auxiliary sources (MAS) when applied to two-dimensional (2D) problems with open boundaries are studied. Although such problems have been examined in the past, the relation of the solution errors with the sources' locations has not been reported in detail. Herein, the convergence behavior in the case of a single infinite wire above a flat ground is thoroughly examined. The dependence of the boundary-condition errors on the number and spacing of the auxiliary sources is illustrated and general rules that govern their behavior are extracted. Finally, a few concluding remarks are outlined and their utilization for the advancement of the MAS is briefly discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 518–522, 2003 [ABSTRACT FROM AUTHOR]

A novel adaptive filter is proposed that adapts to the sample spacing as well as to the tap weights. Although in adaptive digital processing, the tapped-delay line usually has uniformly spaced taps, with the spacing equal to symbol period or a fraction of symbol period, an adaptive filter with a few taps should be adaptively arranged for nonuniform spacing for better convergence as the sampling timing varies. The conventional non-uniformly spaced filters are not adaptively changed or not arranged under the constraint of the acceptable mean-square error. In this paper, a least-mean square (LMS)- type algorithm is derived in which an adaptive filter adaptively changes the amount of delay, as well as the filter coefficients. The performance of the proposed algorithm is investigated by computer simulation. [ABSTRACT FROM AUTHOR]

The array thinning technique can greatly reduce the number of the array elements while keeping the performance of the array almost the same. However, the existing algorithms have slow convergence rates and are easy to fall into local optimum. To improve the optimisation performance, a hybrid method based on improved genetic algorithm (GA) and iterative Fourier transform (IFT) technique for linear thinned array is proposed in this study. The population is divided into improved GA group and IFT group according to the convergence of the population and different operations can be done paralleled to generate offspring in each iteration. In the improved GA processing, adaptive crossover rate and mutation rate are used. The mechanism that keeps the fill factor stable is removed for larger search range. The IFT processing is executed paralleled for fast convergence velocity. The proposed hybrid method can obtain the fast convergence velocity and avoid being trapped into the local optimum by the combination of the two approaches. Several examples are simulated to validate the performance of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, a new position location (PL) estimation technique for CDMA wireless communications system is proposed. The proposed technique provides faster solution to the hyperbolic model and does not suffer from the convergence problem. The performance of the proposed PL technique has been tested by considering different system parameters, such as channel noise and variable position of the user. Test results show that the proposed PL technique can successfully determine the position of a wireless user under various challenging scenarios. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we propose three extended reservation-based multiple access protocols with variable frame length (RMAV) in order to adapt to traffic variation more flexibly. At first, we propose model 1 of the extended RMAV in which the frame length can increase in the next frame as many slots as the terminal needs, while in the conventional RMAV the frame length increases one slot in the next frame. It is shown by computer simulation that the proposed model 1 can attain lower mean message delay and more rapid convergence speed than the conventional RMAV. Next, we propose model 2 of the extended RMAV, which has the function of supporting prioritized traffic and satisfies the different quality of service by using the variable maximum of the slots Rmax, i that the terminal of class i can reserve in one frame. It is shown by numerical analysis and computer simulation that the performance of the higher priority class can surpass that of the lower priority class. Further, to make the reservation more efficiently, we propose model 3 of the extended RMAV, which uses minislots for reservation. It is shown by computer simulation that model 3 can reduce message delay compared to model 1. © 1999 Scripta Technica, Electron Comm Jpn Pt 1, 83(3): 63–73, 2000 [ABSTRACT FROM AUTHOR]

The moment method in the Fourier-transformed domain has been used widely as a rigorous numerical method for analysis of patch antennas, microstrip lines, finlines and planar circuit structures. In this paper, this method has been applied to a planar printed dipole on the grounded dielectric substrate. The integrand in Sommerfeld-type integrals with a slow convergence rate has been modified by means of an effective dielectric constant determined from the asymptotic values for large spectral components so that the convergence can be improved significantly. The method of computing the matrix elements in the moment method, evaluation of the effective radius of a planar dipole and separation of the radiated power and the surface wave power are discussed. Finally, the validity of the method is confirmed by comparison with measured data. In addition, the effect of the substrate thickness on the antenna performance is discussed. [ABSTRACT FROM AUTHOR]

Terminal iterative learning control (TILC) has been developed to reduce the error between system output and a fixed desired point at the terminal end of operation interval over iterations. In this work, the desired terminal point is not fixed but allowed to change run-to-run among a set of fixed points and a new adaptive terminal iterative learning control scheme is developed to achieve learning objective over iterations. The control signal is updated from the measured terminal value at the end of a run, instead of the whole output trajectory. Although the reference terminal point is iteration-varying, the new adaptive TILC guarantees that the tracking error converges to zero iteratively. Both rigorous mathematical analysis and simulation results confirm the applicability and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In wireless sensor and actuator networks (WSAN), sensors can have much longer lifetime as mobile sink nodes move through the network and collect data from static sensor nodes. Applying mobile sinks in WSAN systems has faced challenges in sink path planning and data gathering scheduling. Many studies have focused on priori‐trail planning for mobile sinks; however, they have not considered tracking performance degradation during operation due to system nonlinearities and uncertain WSAN environments. Thus, two learning‐based adaptive feedback control methods, adaptive neural‐network‐based feedback control (ANNFC) and adaptive neural‐network‐based feedback control with integrator model (ANNFC‐IM), are proposed to improve and optimise tracking performance in unknown and uncertain WSAN environments. The proposed algorithms enable a mobile sink to adjust its flying trajectory with online learning by applying a neural‐network‐based control method. The performance of the proposed algorithm is validated by theoretical analysis and simulation results. The results demonstrate that the proposed methods significantly outperform existing methods in terms of tracking error, system stability, and convergence. [ABSTRACT FROM AUTHOR]

Since the transfer function of a two-stage adaptive filter combining a lattice predictor and a FIR filter includes the reflection coefficients and the filter coefficients, a conventional learning algorithm does not integrate the updates of the reflection coefficients and the filter coefficients. Therefore, error reduction could not be guaranteed. To solve this problem, we proposed a learning algorithm that corrects the coefficients of the adaptive filter synchronized to updating the reflection coefficients. The filter coefficients w(n + 1) are corrected so that the transfer function based on the filter coefficients w(n + 1) updated by using the reflection coefficients k(n) updated at sample time n is identical for the reflection coefficients k(n + 1) updated at sample time n + 1, and the filter coefficients w(n + 1) are used in the output calculation for sample n + 1. The computational complexity required for updating is 2 (prediction order × filter order). We conducted a simulation to estimate an unknown system by using white noise, colored noise, and speech as the input signal and compared the performance to a conventional method. We verified the following. The conventional method that does not correct the filter coefficients in response to fluctuations in the reflection coefficients cannot adequately reduce the estimation errors. The proposed method converges 4 to 5 times faster than NLMS for speech input, and its errors are equivalent to those of RLS. When the prediction order ≪ the filter order, the computational complexity can be substantially less than RLS. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(2): 67–78, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10088 [ABSTRACT FROM AUTHOR]

This article investigates the distributed fixed‐time event‐triggered consensus problem for linear multi‐agent systems with input delay. The Artstein‐Kwon‐Pearson reduction approach is used to convert the delay‐dependent system to a delay‐free one. Based on the delay‐free system, two distributed event‐triggered protocols are designed based on local information exchange to address the leaderless consensus and the leader‐follower consensus problems. In the proposed consensus protocols, both continuous controller updates and continuous communication as well as the Zeno behavior are successfully excluded. Detailed convergence analysis demonstrates that the closed‐loop system is fixed‐time stable regardless of the initial conditions. Finally, some simulation examples are provided to validate the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper the superconvergence property of isoparametric bilinear finite elements is considered. A new superconvergence recovery method for isoparametric bilinear finite elements is discovered on the four vertices and the four midpoints of the edges of the elements for piecewise strongly regular quadrilateral subdivisions. [ABSTRACT FROM AUTHOR]

This paper discusses the concept of the minimal value set. Based on the number of connected components of the minimal value set, the unimodal function (number of connected components = 1) and the multimodal function (number of connected components ≧ 2) are defined. Several properties are derived from the relation between the connected level set and the minimal value set, and the unimodal region of a certain minimal value set is defined. Three theorems concerning the minimal value set are derived, as follows. (1) The set of local minimal points includes the minimal value set. (2) The minimal value set includes the set of minimal points in the narrow sense. (3) The unimodal function includes the quasi-convex function. The probability that the multistart method, where the local optimization technique is applied to the multiple candidate points, finds the global minimal point, as well as the necessary condition for the local optimization technique so that the points on the unimodal region containing the global minimal point converge correctly to the global minimal point, are discussed. © 1998 Scripta Technica. Electron Comm Jpn Pt 3, 81(1): 42–51, 1998 [ABSTRACT FROM AUTHOR]

In order to overcome some shortcomings including the premature convergence and slow convergence speed at later evolution stage of conventional cuckoo search (CS) algorithm for the sidelobe suppressions of antenna arrays, an improved CS with reverse learning and invasive weed operators (ICSRLIWO) is proposed. First, ICSRLIWO algorithm generates reverse populations through opposition‐based learning method, then selects better individuals in the mixed population consists of the original and reversed population to form a high‐quality initial population. Second, ICSRLIWO introduces the reproducing, space diffusion and survival competition operators of invasive weed optimization to improve the population diversity and global search ability of conventional CS algorithm. Simulations are conducted based on 30 test functions in the CEC 2014 test suit to verify the performance of the proposed approach, and the results show that ICSRLIWO has higher solution accuracy and faster convergence speed than other comparison algorithms. In addition, ICSRLIWO also has advantages in solving the array antenna beam pattern optimization problems. [ABSTRACT FROM AUTHOR]

Summary: In this article, the problem of event‐triggered‐based fixed‐time sliding mode cooperative control is addressed for a class of leader‐follower multiagent networks with bounded perturbation. First, a terminal integral sliding mode manifold with fast convergent speed is designed. Then, a distributed consensus tracking control strategy based on event‐triggered and sliding mode control is developed that guarantees the multiagent networks achieve consensus within a fixed time which is independent of initial states of agents in comparison with the finite‐time convergence. Furthermore, the update frequency of control law can be considerably reduced and Zeno behavior can be removed by utilizing the proposed event‐triggered control algorithm. Simulation examples are used to show the effectiveness of the new control protocol. [ABSTRACT FROM AUTHOR]

An efficient spectral domain method of moments formulation is derived and presented for a grounded dielectric slab with a number of concentric annular rings placed on the top layer. The structure is excited with microstrip ports placed around the perimeter of the outer ring. The presented method is a novel spectral domain technique in cylindrical coordinates, which employs suitable basis functions for excellent convergence. The convergence and accuracy of the proposed formulation are validated by comparing the rings' surface currents with commercial electromagnetic simulation software. Key Points: A new and efficient circular spectral domain method of moments formulation is derived, which can be applied to cylindrical structuresA multibeam, millimeter wave antenna is proposed and analyzed based on the developed methodThe numerical results based on the this method are validated using the commercial softwares [ABSTRACT FROM AUTHOR]

The authors study the performance of protograph low-density parity-check (LDPC) codes over two-dimensional (2D) intersymbol interference (ISI) channels in this study. To begin with, the authors propose a modified version of finite-length (FL) extrinsic information transfer (EXIT) algorithm so as to facilitate the convergence analysis of protograph codes. Exploiting the FL-EXIT analyses, the authors observe that the protograph codes optimised for 1D ISI channels, e.g. the 1D ISI protograph code, cannot maintain their advantages in the 2D-ISI scenarios. To address this problem, the authors develop a simple design scheme for constructing a family of rate-compatible improved protograph (RCIP) codes particularly for 2D-ISI channels, which not only outperform the 1D-ISI protograph code, but also are superior to the regular column-weight-3 code and optimised irregular LDPC codes in terms of the convergence speed and error performance. More importantly, such RCIP codes benefit from relatively lower error-floor as well as linear encoding and fast decoding. Thanks to these advantages, the proposed RCIP codes stand out as better alternatives in comparison with other error-correction codes for ultra-high-density data storage systems. [ABSTRACT FROM AUTHOR]

Meeting the performance specifications of consolidated web services in a data center is challenging, as the control of the underlying cloud computing infrastructure must meet the service level agreement requirements and satisfy the system's constraints. In this article, we address the admission control and resource allocation problem jointly, by establishing a unified modeling and control framework. Convergence to a desired reference point and stability and feasibility of the control strategy are guaranteed while achieving high performance of the co-hosted web applications. The efficacy of the proposed approach is illustrated in a real test bed. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Communications technologies and services are evolving at a rapid pace. This drives an exponential growth of data consumption. And convergent billing is playing an expanding role. It helps unify technology and supports the interconnectibility of technology, media, and telecommunications (TMT) industries. However, without proper interconnect billing, serious financial losses may result for providing companies. What risks do these trends pose for merger and acquisition (M&A) deals in the TMT industries? [ABSTRACT FROM AUTHOR]

ABSTRACT This article raises the question of the compatibility of 'Postmodern marketing' and 'Mediterranean marketing', challenging the literature on Mediterranean marketing, which qualifies it as postmodern. Do Mediterranean and Postmodern marketing not, in fact, constitute an oxymoron? Or, at the very least, do they not exhibit characteristics that differentiate them much more than the literature contends? The comparative and critical analysis of the convergence of these two types of marketing is based on a literature review and empirical cases. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Under natural viewing conditions, the accommodation and vergence systems adjust the focus and the binocular alignment of the eyes in response to changes in viewing distance. The two responses are linked via cross-coupling and proceed almost simultaneously. Some optical devices, such as virtual reality or helmet mounted displays, create an oculomotor conflict by modifying demands on both vergence and accommodation. Previous studies extensively investigated the effect of such a conflict on the cross-coupling between vergence and accommodation, but little is known about the plasticity of the whole oculomotor system. In the present study, an oculomotor conflict was induced by a telestereoscope which magnified the standard inter-pupillary separation threefold and thus increased the convergence demand while accommodation remained almost unchanged. The effect of a 10 min exposure was assessed via a series of optometric parameters selected on the basis of existing oculomotor models. Associated with subject's visual complaints, most of the oculomotor parameters tested were modified: there was (1) deterioration of stereoscopic threshold; (2) increase in AC/A ratio; (3) increase in near and far phorias; and (4) shift of the zone of clear and single binocular vision towards convergence. These results showed a change in gain of accommodative vergence and a shift of vergence reserves towards convergence in response to telestereoscopic viewing. The subject's binocular behaviour tended towards esophoria with convergence excess as confirmed by Sheard's and Percival's criteria. Such changes in oculomotor parameters support adaptive behaviour linked with telestereoscopic viewing. [ABSTRACT FROM AUTHOR]

An active noise control (ANC) system is proposed that uses a new frequency domain simultaneous perturbation (FDSP) method automatically controlling the magnitude of perturbation. The proposed method automatically controls the magnitude of perturbation so that the convergence speed can be improved substantially over the conventional case where the magnitude of perturbation is fixed. Specifically, when the error signal is large, the magnitude of the perturbation is made large, while the latter is reduced when the error signal is small. As a result, the present system resolves the problem of instability caused by the block process and also the step size can be set to a larger value. The present control is effective when the magnitude of perturbation needs to be set small. In particular, if the magnitude of perturbation is 0.08, the convergence speed is improved by more than 50 times. Also, the present control is effective for suppression of the noise generated due to addition of perturbation. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(2): 43–53, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10112 [ABSTRACT FROM AUTHOR]

Three dimensional electromagnetic wave scattering problems are solved by the perfectly conducting smooth object using the Yasuura method. First, the Yasuura method and its computer-oriented algorithm are described. Second, the convergence and accuracy of solution for scattering from bodies of revolution are checked numerically. numerical results for prolate spheroid indicate that the Yasuura method is accurate and efficient. As a numerical example, the radar cross section of a nonconvex scatterer is calculated. The numerical result shows that the radar cross section of the nonconvex object is significantly different from that of the sphere as indicated in the two-dimensional problem. [ABSTRACT FROM AUTHOR]

The fundamental structure of linear-combined multichannel adaptive digital filters which can process a multiple-input single-output time series, and their tap-coefficient correction algorithms with fast convergence are described. These are fundamental circuits required for multichannel echo-cancellers, and echo-cancellers with noise-cancelling facilities. The structure of linear-combined multichannel adaptive digital filters using the learning identification (LI) was introduced, and their characteristics were analyzed. Adaptive algorithms using the per-channel normalization of power were proposed to improve the convergence speed. With a minor increase in the amount of computations, this method is a significant improvement of the convergence speed which, inherently, is degraded by the differences of average powers among channels in a linear-combined multichannel adaptive filter. For further improvement in the convergence speed, another tap-coefficient correction equation (the projection method) also was introduced. In the tap-coefficient equation using the projection algorithms, the convergence speed can also be improved significantly by applying the per-channel power normalization. [ABSTRACT FROM AUTHOR]