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The triplet Markov fields (TMF) model has been successfully applied to statistical segmentation of nonstationary images by introducing the auxiliary field, which represents the different stationarities of images. Commonly, the TMF adopts a four-nearest neighborhood. This limits the modeling ability for complex priors. Therefore, this paper suggests using a higher order neighborhood-based TMF (HN-TMF). In the HN-TMF, the autocovariance analysis is applied to reveal the local fluctuation at each site. The auxiliary field is then redefined based on the local fluctuation information to denote homogeneity or heterogeneity. Based on the auxiliary field, the local energy function in HN-TMF is constructed either in a homogeneous or heterogeneous way, and hence, the local structure can be embedded in the energy function to improve the prior modeling ability. Along with the newly constructed energy function, new initializations of HN-TMF parameters are given to fulfill the physical interpretation of the energy function. The experiments performed on both synthetic and real synthetic aperture radar images demonstrate the effectiveness of the proposed HN-TMF in both speckle noise reduction and heterogeneous region segmentation accuracy. [ABSTRACT FROM PUBLISHER]

A recently developed image resizing technique, seam carving, has been proved to be a useful tool for content-adaptive spatially nonuniform image resizing with the purpose of optimal display on a screen of reduced resolution or different aspect ratio. In this paper, we present a fast algorithm for real-time content-aware video retargeting based on the improved seam carving method proposed in this paper. The proposed algorithm is designed to be highly parallelizable and suitable for running on a multicore architecture. First, two novel operators, i.e., seam update and seam split, are introduced to analyze an image for detecting the local and global seams with minimum costs very efficiently. With these operators, parallel processing can be achieved to determine multiple seams simultaneously. In addition, the saliency measure is extended with a just-noticeable-distortion model which makes the resized video more consistent with human perception. We demonstrate the efficiency of the above new components with a graphics processing unit (GPU) implementation. In addition, the proposed fast seam carving algorithm is extended for video retargeting. To the best of our knowledge, this is the first paper based on the seam carving method to achieve real- time video retargeting on a GPU. Experimental results on video sequences of various characteristics are demonstrated to show the superior performance of the proposed algorithm in comparison with the existing content-adaptive image/video resizing methods. [ABSTRACT FROM AUTHOR]

Mobile WiMAX was successfully adopted by ITU as one of the IMT-2000 technologies in November 2007. Since then mobile WiMAX (a.k.a. IP-OFDMA) has officially become a major global cellular wireless standard along with 3GPP UMTS/HSPA and 3GPP2 CDMA/EVDO. Mobile WiMAX is an OFDM-based technology available for deployment today, and new WIMAX devices come to market at much reduced cost than that of current 3G solutions. Currently over 260 service providers are deploying fixed, portable and mobile WiMAX networks in 110 countries. This article provides an overview of the mobile WiMAX system and its performance under various configurations, channel conditions, and types of data traffic. Furthermore, the article provides an overview of mobile WiMAX evolution. [ABSTRACT FROM AUTHOR]

In this paper, we take an information-theoretic approach to obtaining optimal code rates for error-control codes on a magnetic storage channel approximated by the Lorentzian channel. Code rate optimality is in the sense of maximizing the information-theoretic user density along a track. To arrive at such results, we compute the achievable information rates for the Lorentzian channel as a function of signal-to-noise ratio and channel density, and then use these information rate calculations to obtain optimal code rates and maximal linear user densities. We call such (hypothetical) optimal codes "Shannon codes." We then examine optimal code rates on a Lorentzian channel assuming low-density parity-check (LDPC) codes instead of Shannon codes. We employ as our tool extrinsic information transfer (EXIT) charts, which provide a simple way of determining the capacity limit (or decoding threshold) for an LDPC code. We demonstrate that the optimal rates for LDPC codes coincide with those of Shannon codes and, more important, that LDPC codes are essentially capacity achieving codes on the Lorentzian channel. Finally, we use the above results to estimate the optimal bit-aspect ratio, where optimality is in the sense of maximizing areal density. [ABSTRACT FROM AUTHOR]

Discusses two problems on optimal filtering for uncertain systems containing deterministic and stochastic properties. Design of a linear time-invariant filter; Mean energy gain between the noise affecting the system and the estimation error; Presentation of filtering algorithms.

This paper presents a fuzzy stochastic prediction method for real-time predicting of stock prices. A complete contrast to the crisp stochastic method, it requires a fuzzy linguistic summary approach to computing parameters. This approach, which is found to be better than the gray prediction method, can eliminate outliers and limit the data to a normal condition for prediction, with a comparatively very small deviation of 4.5 percent. [ABSTRACT FROM AUTHOR]

Proposes a unified approach for generating chaos in continuous-time affine systems, based on the normal form of chaotic systems and nonlinear control theory. Feedback-control law designed to make a feedback linearizable system topologically conjugate to a reference chaotic system; Relative degree of a given feedback unlinearizable system; Corresponding internal dynamics of the system.

We present algorithms for the solution of two problems in array pattern synthesis. The first is the design of nonuniform arrays with a desired magnitude response. The second is that of robust design, i.e., design in the presence of uncertainties. Constraints such as power limitation can be addressed with both problems. The algorithms that we present are based on semidefinite programming, for which efficient software is readily available. We present examples that illustrate the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

Presents a robust recursive Kalman filtering algorithm that addresses estimation problems arising in linear time-varying systems with stochastic parametric uncertainties. Applications of recursive minimum mean-square error estimators; Initialization of the robust Kalman filter; Connection with the conventional Kalman filtering algorithm; Convergence of the robust Kalman filter.

Describes the scale-free dynamical network model. Presentation of a stability criterion for synchronization in a dynamical network; Investigation of the synchronizability of scale-free dynamical networks; Analysis of the robustness of the synchronizability of a scale-free dynamical network with respect to random or specific removal of a small number of nodes.

Focuses on building a practical chaotic time-delay circuit based on a standard Chua's circuit by adding a small-amplitude time-delay voltage feedback in a nominal Chua's circuit. Investigation of the synchronization of chaotic Chua's circuit with application to secure communication; Overview of the time-delay-feedback Chua's circuit; Simulation results.

Presents a study which developed a time-delay feedback control approach for making a continuous-time minimum-phase system chaotic. Methodology; Results; Discussion.

Proposes an analytical approach for solving the steady state of nonlinear electric circuits including ferromagnetic coils. Mathematical model that describes the performance of the approach; Linear differential equation system; Nonlinear algebraic equation system; Successful employment of the related algorithm in computer simulation for different nonlinear circuits.

Presents information on a study which examined the problem of making a stable linear time-invariant system chaotic by using state-feedback control of arbitrarily small magnitude. Problem description and controller design; Conclusions.

Proposes a generalized outage table approach for analyzing the reliability of bus schemes of power stations. Influences of different bus schemes on the reliability of power stations; Contention that a proposed algorithm is practical and efficient; Description of algorithm.

In this paper, a simple and nondestructive method of modeling 40-nm interconnects is proposed. Traditional methods based on charge-based capacitance measurement model the interconnects by fitting the capacitance or resistance curves, first by assuming one constant process parameter, such as metal thickness, and then by extracting the metal width, metal spacing, and inter-level dielectric (ILD) thickness from certain test patterns that may therefore result in model inaccuracy while the transmission and scanning electron microscopy methods are both destructive and time consuming. The proposed new methodology directly extracts the metal width based on the metal resistance test structures, and then the metal thickness, metal spacing, and ILD thickness without any presumption. It is also nondestructive and fast, with a model accuracy higher than 95%. Furthermore, with the ensured accuracy of layout parameter extraction, the necessity of an accurate interconnect model in the 40 nm technology and beyond is emphasized. [ABSTRACT FROM AUTHOR]