Search

Lyapunov exponents of a dynamical system give information about its long-term evolution. Exponents estimation is not an easy task; it is computationally costly and, in presence of chaotic dynamics, it exhibits numerical difficulties. In a previous paper, the authors proposed an algorithm for Lyapunov exponents estimation in piecewise linear systems that strongly reduces the computational time. In this paper, the algorithm is applied also to chaotic systems with polynomial nonlinearity. Firstly, a suitable piecewise linear approximation for the polynomial nonlinear function is evaluated by means of a Multi-Layer Perceptron neural network with linear and saturating linear transfer functions. Then, the linearity of the new state equation and of the variational equation, obtained resorting to the piecewise linear approximation of the nonlinear function, are exploited to accurately evaluate Lyapunov exponents of the approximated system with a reduced execution time.

In this paper the differential kinematics for cable-driven robots is derived and the use for calibration, system investigation and a force based forward kinematics is shown. The Jacobians for each part of the kinematic chain are derived with respect to the platform pose and the most important system parameters. Beside the consideration of geometrical quantities, the differential relations between non-geometrical quantities such as cable stiffness and cable forces are determined. The decomposition in the most fundamental Jacobians allows to analyse and compute more complex relations by reassembling the Jacobians as needed. This approach allows more insight in the system behavior and enables the reuse of the individual modules. The purpose of this paper is to provide the framework and the key equations and to show the use for calibration, force based forward kinematics and system analysis as well as for control purposes.

The year 2005, under the auspices of the United Nations Organization (UNO), was celebrated as the International (or World) Year of Physics. It was as much in the memory of that Annus Mirabilis (Miracle Year) of 1905 in which Albert Einstein published his five famous papers [1–5] more than a century ago, as to honor their author himself by the whole world together. We now know the profound effects those five papers [1–5] have had not only on the development of science, in general, and physics, in particular; but also on the evolution, through these developments, of the human civilization we are enjoying today. One [1] of the five papers which Einstein wrote in the Annus Mirabilis, provided an explanation of the experimentally observed photoelectric effect [6, 7].

This paper addresses the problem of using a fleet of autonomous watercraft to create models of various water quality parameters in complex environments using intelligent sampling algorithms. Maps depicting the spatial variation of these parameters can help researchers understand how certain ecological processes work and in turn help reduce the negative impact of human activities on the environment. In our domain of interest, it is infeasible to exhaustively sample the field to obtain statistically significant results. This problem is pertinent to autonomous water sampling where hysteresis in sensors causes delay in obtaining accurate measurements across a large field. In this paper, we present several different approaches to sampling with cooperative vehicles to quickly build accurate models of the environment. In addition, we describe a novel filter and a specialized planner that uses the gradient of sensor measurements to compensate for hysteresis while ensuring a fast sampling process. We validate the algorithms using results from both simulation and field experiments with four autonomous airboats measuring temperature and dissolved oxygen in a lake.

As the core technology of intelligent monitoring system, the moving target detection method plays an important role in the intelligent monitoring system, but the current moving target detection method still has some shortages such as lower anti-jamming performance on the environment, low judge accuracy and so on. In this paper, the improved background subtraction based on mixed Gaussian probability background model is used, local optical flow algorithm is introduced to achieve the unconstrained stable initialization of background model, the added items which are sensitive to global illumination conditions are adopted to assist the adaptive updating of model parameters, eventually the improved algorithm framework are formed and combined with processing method after testing to extract the information of effective movement area and realize the judgment of break in of foreign matters. Finally, the overall realization of intelligent monitoring system is expounded theoretically in the paper, based on the improved moving target detection method, the factors of characteristics of moving targets which affect the detecting precision are analyzed systematically, so it shows that this moving target detection method can improve the detecting precision of intelligent monitoring system and has good real time, accuracy and reliability.

Word boundary ambiguity is a major problem for the Thai morphological analysis since the Thai words are written consecutively with no word delimiters. However the part of speech (POS) tagged corpus which has been used is constructed from the academic papers and there are no researches that worked on the documents written in the informal language. This paper presents Thai morphological analysis with unknown word boundary detection using both POS tagged and untagged corpora. Viterbi algorithm and Maximum Entropy (ME) - Viterbi algorithm are employed separately to evaluate our methods. The unknown word problem is handled by making use of string's length in order to estimate word boundaries. The experiments are performed on documents written in formal language and documents written in informal language. The experiments show that the method we proposed to use untagged corpus in addition to tagged corpus is efficient for the text written in informal language.

It is challenging to count and analyze people in crowds due to the changes of lighting, occlusions, shadows, backgrounds, and weather conditions. Especially for the occlusion problem, until now, it is still ill-posed. To deal with the occlusion problem, the MCMC (Monte Carlo Markova Chain) scheme is used in this paper to estimate all possible pedestrian positions across different frames. However, it requires good initial head positions for parameter searching and people counting. Thus, an intelligent head-shoulder-region detector is then developed for detecting all possible pedestrian candidates from videos. One key problem in head-shoulder detection is that the feature contrast between the objects and their background should be larger. To tackle this problem, a Linear Discriminant Analysis (LDA) approach is then used to enhance the boundaries between objects and features. Three contributions are made in this paper: (1) Intelligent head-shoulder-region detector; (2) People detection under occlusions; (3) Integrated people counting system using LDA. Experimental results have proved the superiorities of the proposed method in people detection and counting.

Today’s modern human life-style is in a great uplift with respect to anything and everything. The requirement of road transportation and vehicles is increasing day-by-day which is proportional to the number of accidents happening eventually. At this juncture, building an intelligent vehicle system and other safety driven driver assistance systems have become the order-of-the-day. Despite the fact that considerable research has been carried out in detecting and tracking the traffic signs, still there is a huge lack in pertinent traffic sign recognition systems, especially in countries like India. This paper designates on the implementation of iReSign, next-generation two-tier identity classifier-based traffic sign recognition system architecture using Zernike and GFD algorithms for the future intelligent vehicle systems. Further, this paper details the results and its analysis, which is based on 840 images of 28 distinct traffic signs of India (collected manually). Using Zernike Moments and Generic Fourier Descriptors (GFD) region-based global shape recognition techniques, iReSign produced 78.33%, 90% cross validation accuracy and 77.85%, 91% testing recognition accuracy respectively. Using our new hybrid approach of combining Zernike Moments and GFD, iReSign produced 92% cross validation accuracy and 95% testing recognition accuracy.

In three papers [1–3] the present author applied the concept of time-rescaled Brownian motion to aspects of relativistic interstellar flight ranging from communication theory to genetics. The content of the present chapter was fully published in paper form in [11].

Given a search query, most existing search engines simply return a ranked list of search results. However, it is often the case that those search result documents consist of a mixture of documents that are closely related to various contents. In order to address the issue of quickly overviewing the distribution of contents, this paper proposes a framework of labeling blog posts with Wikipedia entries through LDA (latent Dirichlet allocation) based topic modeling. More specifically, this paper applies an LDA-based document model to the task of labelling blog posts with Wikipedia entries. One of the most important advantages of this LDA-based document model is that the collected Wikipedia entries and their LDA parameters heavily depend on the distribution of keywords across all the search result of blog posts. This tendency actually contributes to quickly overviewing the search result of blog posts through the LDA-based topic distribution. In the evaluation of the paper, we also show that the LDA-based document retrieval scheme outperforms our previous approach.

The Coanda effect, invented by Henri Marie Coanda is an interesting phenomenon in fluid mechanics. The basics of the Coanda effect is based on the property of a jet flow to attach itself to a nearby surface and to remain attached even when the surface bends away from the initial jet direction. This effect has been applied in many areas since 1960. In the recent years, researches have been initiated towards the application of Coanda effect in robots. This paper is focused on the utilization of Coanda effect in the field of robotics. The research that the authors are carrying out in this area is also addressed at the end of this paper.

Conditional simulation approach is the major trend and reseach focus of geostatistic development. In this paper, simulation result, statistical parameters and variogram is analysized by applying sequential indicator simulation to reservoir modeling, besides, the comparison between kriging and sequential simulation method has been made. The result proves the characteristic of conditional simulation and enriches the theory. This paper discusses indicator variation function and indicator model, the smoothing effect of kriging estimation can be seen from simulation results. Finally, the sequential conditional method has been applied to reservoir simulation modeling and theoretical basis and example provides a wide range of choices to describe the real geological conditions.

In this paper, we describe a model for extracting rules that describe enterprise resource planning (ERP) system upgrade process. The rules are extracted automatically by analyzing programming code from completed ERP systems upgrade projects. Later those rules are verified and tuned by experienced programmer. The rules that we are extracting are described in the language equivalent to the first-order logic (i.e. expressivity of Turing machine). Nevertheless, we put a constrain on the rules description language by defining how knowledge base is used to define these rules. We require that ERP system code and ERP upgrade knowledge base must be transformed to a series of aligned strings without lost of expressivity. Such strong requirement ensures that we are able to use existing machine learning algorithms in the process of software development and upgrade. These series of strings are compared by strings manipulation algorithms and then differences are resolved by merge algorithm presented in this paper. We used Microsoft Dynamics NAV as an example to test usefulness of presented method but other systems can be used as well if they can be presented as series of code strings.

In this paper, the induction heating power supply adopting cascaded multilevel inverter was the study object. For improving the quality of output voltage in induction heating power supply inverter, a harmonics control mean of output voltage by selecting switching angles were presented. The harmonics equation system of output voltage in two modules cascaded multilevel inverter were established based on the Fourier expression of the output voltage. Based on the work characteristic of induction hearting power supply, the calculation method of eliminating harmonics and the reasonable advice about switching angles were given. Simulation and experiment results shown the total harmonic distortion (THD) of output voltage can be reduced by adopting the harmonics control mean presented in this paper.

During the course of prediction and estimation to the target in opto-electronic tracking system, stochastic noises statistical character affects the precision badly. To solve this problem, set-membership estimation is introduced to the target prediction in this paper. Considering the non-linear feature of opto-electronic tracking system, the paper analyzes extend optimal bounding ellipsoid (EOBE). Result of simulation shows that, compared with extend kalman filter (EKF), the prediction precision of EOBE is almost as good as that of EKF. Especially when the noise is bounded but not white and Gaussian, EOBE has better robustness.

In order to solve the problems of deviations with large error occurred at the sharp corners of motion trajectories and poor stability of tracking algorithm presented in previous paper, and further make improvements to the tracking precision, in this paper the rather appropriate state model is established first of all, and then the effective observations are collected by using spatial-temporal detection and fusion in which the brightness information of the target included in the decision criteria for the first time. Under the different circumstances of Gaussian noise and non-Gaussian noise, the experimental results show that take the Gaussian particle filter as the tracking algorithm which has no use of re-sampling could have effectively improved the precision of algorithm for tracking dim moving point target in IR image sequences, and has a good real-time performances and good stability.

In this paper, the potential of unlocking wing sweep on aircraft drag reduction is explored in the context of recent development in shock control by three dimensional bumps on natural laminar flow(NLF) wings. Reduction of the wing sweep currently employed for large transport transonic aircraft is advocated for significant drag reduction, enabling natural laminar flow wing development with shock control. The aim is to unlock a normally fixed design variable (for large transonic aircraft), i.e. wing sweep, in order to achieve substantial drag reduction through extended natural laminar flow area while keeping the shock strength and its impact on wave drag under control. A decrease of the current transonic wing sweep angle is anticipated to accommodate the natural laminar flow target, because of the potential alleviation of attachment line transition and crossflow boundary layer instability. The paper demonstrates the effects of 3D shock control bumps from zero to 20sweep and from 2D sectional to 3D NLF wings for cruise Mach number from 0.68 to 0.85.

In a previous paper we have shown that membrane systems with controlled mobility are able to solve a $\Pi_2^\mathrm{P}$ complete problem. Then, an enriched model with forced endocytosis and forced exocytosis enables us to move to the fourth level in the polynomial hierarchy, the model having $\Sigma_4^\mathrm{P} \cup \Pi_4^\mathrm{P}$ as lower bound. In this paper we study the computability power of this model (using forced endocytosis and forced exocytosis), and determine the border condition for achieving computational completeness: 4 membranes provide Turing completeness, while 3 membranes do not. Moreover, we show that the restricted division operation (which is crucial in achieving the $\Sigma_4^\mathrm{P} \cup \Pi_4^\mathrm{P}$ lower bound) does not provide computational completeness. However, Turing completeness can be achieved with pairs of operations (exocytosis, inhibitive endocytosis) and (inhibitive exocytosis, endocytosis) by using 4 membranes. Finally, we present some computability results expressing that membrane systems which use the operations of restricted division, restricted exocytosis and inhibitive endocytosis cannot yield computational completeness.

The process of segmentation consists of dividing the image in regions with similar characteristics. In other words, segmentation is the partitioning of digital images into several regions, according to a given criteria [6]. In addition, applying biometrics to daily scenarios involves difficult and challenging requirements in terms of software and hardware. On the contrary, current biometric techniques are also being adapted to present-day devices, like mobile phones, laptops and the like, which are considered to be unconstrained and contact-less. In fact, achieving a combination of both necessities is one of the most difficult problems at present in biometrics. Segmentation in these kind of environments require special effort and attention, since although there exist an obvious difficulty in providing accurate segmentation to these scenarios, the constraints in terms of software and hardware are important and affect the segmentation performance. Therefore, this paper presents a segmentation algorithm able to provide suitable solutions in terms of precision for hand biometric recognition, considering a wide range of backgrounds like carpets, glass, grass, mud, pavement, plastic, tiles or wood. Results highlight that segmentation accuracy is carried out with high rates of precision (F-measure≥ 88%), presenting competitive time results when compared to state-of-the-art segmentation algorithms time performance. Finally, the accuracy of the proposed method is compared to the performance of Normalized Cuts in terms of segmentation accuracy and time performance.

This paper investigates the hybrid chaos synchronization of identical Arneodo systems (1981), identical Rossler systems (1976) and non-identical Arneodo and Rossler systems. In hybrid synchronization of chaotic systems, one part of the systems is synchronized and the other part is anti-synchronized so that complete synchronization (CS) and anti-synchronization (AS) co-exist in the systems. The co-existence of CS and AS is very useful in secure communication and chaotic encryption schemes. Active nonlinear control is the method used for the hybrid synchronization of the chaotic systems addressed in this paper. Since the Lyapunov exponents are not required for these calculations, the active control method is effective and convenient to achieve hybrid synchronization of the two chaotic systems. Numerical simulations are shown to verify the results.

In this paper we consider the issue of Distributed Video Coding (DVC) over practical channel which involves Gaussian noisy channel. Since the research on DVC over practical channel with respect to modulation is still incomplete this paper does a comprehensive study on DVC modulation techniques to fill the gap. It discusses the suitability of M-Ary modulation to DVC on the basis of energy consumption. The study covers both theoretical and practical aspects through the practical implementation of DVC encoder and decoder, the performance in terms of bit error rate, decoder complexity and data rate of M-Ary modulation techniques used with M-Ary LDPC coding

Recently, there has been a number of papers relating mechanism design and privacy (e.g., see [1-6]). All of these papers consider a worst-case setting where there is no probabilistic information about the players' types. In this paper, we investigate mechanism design and privacy in the Bayesian setting, where the players' types are drawn from some common distribution. We adapt the notion of differential privacy to the Bayesian mechanism design setting, obtaining Bayesian differential privacy. We also define a robust notion of approximate truthfulness for Bayesian mechanisms, which we call persistent approximate truthfulness. We give several classes of mechanisms (e.g., social welfare mechanisms and histogram mechanisms) that achieve both Bayesian differential privacy and persistent approximate truthfulness. These classes of mechanisms can achieve optimal (economic) efficiency, and do not use any payments. We also demonstrate that by considering the above mechanisms in a modified mechanism design model, the above mechanisms can achieve actual truthfulness.

Two coaxial jets which interact and mix belong to the class of flows which are of great interest from both the research and industrial point of view. They have a simple geometry but still the possibility to easily change various parameters makes them suitable for studies of different phenomena related to stability, mixing and turbulence. The definition of the variables able to control the flow dynamics has high applicative potential because coaxial jets are a prototype of many industrial burners but, on the other hand, they are simple enough to be experimentally characterized in laboratory. Due to the high number of parameters able to influence the flow evolution, a complete characterization of such flow is still missing and, therefore, motivates this paper. An experimental analysis of the dominant instabilities in the near field of two coaxial jets has been performed in order to determine the leading processes which start the transition from the initial laminar state, where the two streams are segregated, to the turbulent state. Different inner/outer jet velocity pairs (Ui,Uo) have been tested in order to investigate the effect of both velocity ratio ru = Uo/Ui and Reynolds number. Three main instabilities have emerged depending on the velocity ratio as can be appreciated from figure 1(a) where isocontours of the dominant frequencies have been plotted. For ru < 0.75, the coaxial jets dynamics are driven by the inner shear layer instability, in agreement with [1]. For ru > 1.6, the outer shear layer dominates the near field vortex dynamics [2, 3] while, for ru nearly unitary (i.e. where 0.75 < ru < 1.6), the vortex shedding behind the separating wall imposes its own dynamics [4]. The latter phenomenon is clearly shown in figure 1(b) where a flow visualization of the near field at ru = 1 is reported. Behind the inner separating wall there is a flow pattern composed by staggered vortices which influence the dynamics of the outer shear layer too. An improved scaling relationship for the Strouhal number StŒ tx is proposed in order to calculate the shedding frequency inside the intermediate velocity ratio region. This relationship takes into account Reynolds number as well as velocity ratio effects and leads to a constant Strouhal number value in the whole region where vortex shedding is observable, as showed in figure 2. The present paper confirms experimentally the theoretical results of [5], who proposed that the wake behind the separation wall between the two streams of two coaxial jets creates the conditions for an absolute instability. Evidences of the dominance of the vortex shedding phenomenon in the whole near field inside a certain range of velocity ratios will be presented in the paper. The characterization of this operating region is of utmost importance because the vortex shedding provides a continuous passive forcing mechanism for the control of the flow field, opposite to conventional strategies which use active methods focused to control the outer shear layer dynamics [3]. Therefore, these results allow many improvements in the industrial geometries where coaxial jets are employed by means of just a proper choice of the exit geometry.

The minimum Steiner tree problem has wide application background, such as transportation system, communication network, pipeline design and VISL, etc. It is unfortunately that the computational complexity of the problem is NP-hard. People are common to find some special problems to consider. Since the complexity of the Steiner tree problem, the almost of papers are relate to the object of small data problem, i.e., the number of involved objects is small. Those conclusions are useful to the theoretical research from which some algorithms are originated. For the practical problems, there are large number of objects are need to be considered. In this paper, we introduce an approximate algorithm and give an example with seven objects to consider the location-selection of wireless network problem.

This paper investigates the performance of different hybrid push-pull systems with a decoupling inventory at the semi-finished products and reordering thresholds. Raw materials are ‘pushed’ into the semi-finished product inventory and customers ‘pull’ products by placing orders. Furthermore, production of semi-finished products starts when the inventory goes below a certain level, referred to as the threshold value and stops when the inventory attains stock capacity. As performance of the decoupling stock is critical to the overall cost and performance of manufacturing systems, this paper introduces a Markovian model for hybrid push-pull systems. In particular, we focus on a queueing model with two buffers, thereby accounting for both the decoupling stock as well as for possible backlog of orders. By means of numerical examples, we assess the impact of different reordering policies, irregular order arrivals, the set-up time distribution and the order processing time distribution on the performance of hybrid push-pull systems.

The short-term frequency stability of satellite on-board clock is of great significance for GNSS applications, such as satellite clock modeling, simulation and clock offset prediction. In this paper, four short-term frequency stability estimation methods are analyzed, which need observation data from only one station in contrast with ODTS needing continuous observation of large ground monitoring networks. Performance and accuracy of all these four methods is analyzed and compared using GPS and COMPASS observation data, and their advantage and disadvantage are discussed correspondingly. For COMPASS and Galileo systems which are currently in the early stage of construction, this paper proposes some meaningful suggestions of on-board clock short-term frequency stability estimation.

In this paper a novel three dimensions chaotic system with uncertain parameters and lorenz hyperchaotic system are as examples, the function projective synchronization and parameters identification of different hyperchaotic systems are researched. First, based on the Lyapunov theory of stability and adaptive control method, the adaptive nonlinear controller and adaptive identifying rule to uncertain parameter are designed logically. And by the controller and identifying rule, the function projective synchronization of different systems between three dimensions response system with uncertain parameter and drive system is realized. Second, the feasibility of the controller and identifying rule to uncertain parameter designed in this paper is analyzed theoretically, and the function projective synchronization and parameters identification are proved strictly theoretically. Finally, the theoretical results are verified by numerical simulation.

Mobile processors, a subclass of embedded processors, are increasingly employing multicore designs to improve performance. This often requires sacrificing resources in each CPU, degrading single thread performance which is still important according to Amdahl's law. The traditional technique for efficiently boosting serial performance in embedded processors, dedicated hardware acceleration, is unsuitable for modern mobile processors because of the heterogeneity and the diversity of applications they run. This paper proposes ‘general purpose' accelerators, reconfigured on an application-by-application basis, as a means of increasing single thread performance. These accelerators are placed within the datapath of CPUs and support dynamic compilation. This paper presents the design of an architecture with such accelerators and evaluates the cost/performance implications of the design.

This paper investigates the problem of designing active feedback controllers for achieving generalized projective synchronization (GPS) of identical hyperchaotic Lu systems (Chen et al. 2006) and non-identical hyperchaotic Cai system (Wang and Cai, 2009) and hyperchaotic Lu system. The synchronization results (GPS) derived in this paper have been established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the active feedback control method is very effective and convenient for achieving the general projective synchronization (GPS) of hyperchaotic Lu and hyperchaotic Cai systems. Numerical simulations are shown to demonstrate the effectiveness of the synchronization results derived in this paper.

This paper investigates the backstepping control design with recursive feedback input approach for achieving global chaos synchronization of identical hyperchaotic Liu systems(2001). Our theorem on global chaos synchronization for hyperchaotic Liu systems is established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the backstepping control method is effective and convenient to synchronize the hyperchaotic Liu systems. Numerical simulations are also given to illustrate the synchronization results derived in this paper.

CAPTCHA stands for Completely Automated Public Turing test to distinguish Computers and Humans apart. CAPTCHA is a program which can generate and grade the tests that it itself cannot pass. The security aspect of CAPTCHA should be such that none of the computer program should be able to pass the tests generated by it even if the knowledge of the exact working of the CAPTCHA is known. The effectiveness of CAPTCHA of a given strength is determined by how frequently the guesses of CAPTCHA can be tested by an attacker. This paper proposes a simple and uniform framework for the assessment of security and usability of CAPTCHA that arbitrary compositions of security measures can provide”. In this sentence instead of ”a simple and uniform framework”, use ”parameters”. This paper proposes parameters for the assessment of security and usability of CAPTCHA that arbitrary compositions of security measures can provide.The pre-processing attack on targeted CAPTCHA is demonstrated having success rate of approximately 97% which in turn helps to build more robust and human friendly CAPTCHA. The universal structure for segmentation attack is framed to analyze security of CAPTCHA.

This paper considers a scenario where two parties having private databases wish to cooperate by computing a data mining algorithm on the union of their databases without revealing any unnecessary information. In particular, they want to apply the decision tree learning algorithm ID3 in a privacy preserving manner. Lindell and Pinkas (2002) have presented a protocol for this purpose, which enjoys a formal proof of privacy and is considerably more efficient than generic solutions. The crucial point of their protocol is the approximation of the logarithm function by a truncated Taylor series. The present paper improves this approximation by using a suitable Chebyshev expansion. This approach results in a considerably more efficient new version of the protocol.

In their previous papers, the authors of this study have suggested and realized a method of simultaneous determination of temperature and salinity of seawater using laser Raman spectroscopy, with the help of neural networks. Later, the method has been improved for determination of temperature and salinity of natural water using Raman spectra, in presence of fluorescence of dissolved organic matter as dispersant pedestal under Raman valence band. In this study, the method has been further improved by compression of input data. This paper presents comparison of various input data compression methods using feature selection and feature extraction and their effect on the error of determination of temperature and salinity.

This paper addresses the performance enhancement of speech processing applications like speech recognition, speaker identification and language identification in the presence of additive noise with help of proposed adaptive and iterative Wiener filter. This paper deals with the problem of single microphone, frequency domain speech enhancement in noisy environments using Wiener filter in iterative and adaptive manner based on the speech signal statistics (mean and variance). The algorithm achieves good temporal resolution while maintaining formant and harmonic trajectories. The results of implementation of such a structure will demonstrate significant improvements in Oriya isolated word recognition, Oriya continuous digit recognition, speaker identification and language identification performance under noisy conditions. The accuracy of all above applications is increased by 3% to 8% in average due to the proposed speech enhancement technique incorporation in our ongoing research works.

Shannon’s seminal paper of 1948 [32] is popularly seen as the cornerstone of information theory. Arguably Shannon’s paper addressed a significant problem of the age, namely the scientific quantification of the rather abstract concept of information. Despite numerous earlier works, predominantly by Nyquist, Kupfmuller, Gabor, and Hartley [15, 17, 22, 28], each fundamentally failed in a number of ways. Foremost of these deficiencies is that no rigorous treatment was given to the role of noise, although its importance was noted by both Nyquist and Hartley. Noise is an essential component to information transfer because random, and hence unpredictable, perturbations to an information carrying signal ultimately prohibit exact determination of the original signal or its implicit meaning. The probabilistic treatment of Shannon (and later contributors [30, 34, 39]) allowed the stochastic nature of noise to be considered in a concise and rigorous fashion, and thus a definition for information was born.

The paper is devoted to numerical simulation of processes accompanying underwater explosion near the free surface. In spite of the fact that the problem has been attracting attention of many researchers (see, for example, [1, 2, 3]) challenging problems still remain. The main attention in this paper is paid to compressible and rarefaction wave propagation, to their interaction with each other and with the liquid-gas interface, to deformation of the free surface.

This paper focuses on P systems with one-symbol insertion and deletion without contexts. The main aim of this paper is to consider the operations applied at the ends of the string, and prove the computational completeness in case of priority of deletion over insertion. This result presents interest since the strings are controlled by a tree structure only, and because insertion and deletion of one symbol are the simplest string operations. To obtain a simple proof, we introduce here a new variant (CPM5) of circular Post machines (Turing machines moving one-way on a circular tape): those with instructions changing a state and either reading one symbol or writing one symbol. We believe CPM5 deserves attention as a simple, yet useful tool. In the last part of the paper, we return to the case without priorities. We give a lower bound on the power of such systems, which holds even for one-sided operations only.

This paper investigates the hybrid synchronization of hyperchaotic Chen systems (Jia, Dai and Hui, 2010) via sliding mode control. The stability results for the sliding mode control based synchronization schemes derived in this paper are established using Lyapunov stability theory. The sliding mode control method is very effective and convenient to achieve global chaos synchronization of the identical hyperchaotic Chen systems because the Lyapunov exponents are not required for these calculations. Numerical simulations are presented to demonstrate the sliding mode control results derived in this paper for the hybrid synchronization of identical hyperchaotic Chen systems.

This paper analyzes the Paris Metro Pricing (PMP) strategy for differentiating Internet service. PMP has several advantages over other pricing schemes that guarantee quality of service (QoS) such as simplicity and less bandwidth overhead. In this paper, we develop a simple analytical model for PMP. We first assume that there is only one network service provider (a monopolist) serving N users and model the user behavior and the provider’s profit. Then we derive the optimal ratio of dividing a given network capacity in order to maximize the profit of the service provider. Our results show that, by maximizing providers profit, the subscription is also maximized which can be interpreted as a higher satisfaction of users compared to that of not using PMP. In addition, by taking into account various network types, we show that in a monopoly environment, it is always better to implement PMP regardless of user populations we considered. We then further extend our model to a duopoly setting. We found that there exist no Nash equilibrium even when both providers do not differentiate the network service.

Performance evaluation of computer software or hardware architectures may rely on the analysis of a complex stochastic model whose specification is usually given in terms of a high level formalism such as queueing networks, stochastic Petri nets, stochastic automata or Markovian process algebras. Compositionality is a key-feature of many of these formalisms and allows the modeller to combine several (simple) components to form a complex architecture. However, although these formalisms lead to relative compact specifications of possibly complex models, the derivation of the performance indices may be computationally very time and space consuming since the set of possible states of the model tends to grow exponentially (or even faster) with the number of components. In this paper we focus on models with underlying continuous time Markov chains (CTMCs) and we introduce a notion of typed lumpability, which gives sufficient conditions under which a lumping of the process can be derived, allowing the exact computation of marginal stationary probabilities of the cooperating components. The peculiarity of our method relies on the fact that lumping is applied at the component-level rather than to the CTMC underlying the joint process, thus reducing both the memory requirements and the computational cost of the subsequent solution of the model. Moreover, we investigate the properties of the lumping of reversed automata and we prove that, if these are reversible, a conditional product-form solution of their cooperation with other non-blocking automata can be derived. Although conditional product-forms have been previously investigated by other authors with the aim of approximating non-product-form models, the contribution of this paper consists in giving sufficient conditions for this approach to yield exact results and providing examples to support the modeller’s intuition.

A detector is said to be superior if the information is extracted in a best way for some particular purpose. Here the objective of this paper is to analyze the detection performance of non-coherent detectors such as square law detector, linear detector and logarithmic detector in a background of white Gaussian noise (WGN) for Ultra Wide Band Short Range Radar in Automotive applications. It is assumed that the target is stationary and energy reflected from the target is distributed. The non-coherent detectors have almost similar detection probability in a background of white Gaussian noise. The performance of the detector is analyzed and simulation has been done in order to verify.

In 1951, Hopf [9] published a theorem in a seminal paper on surfaces of constant mean curvature which can be stated as follows. Let a genus zero compact surface M be immersed in \({\mathbb{R}^3}\) with constant mean curvature H. Then M is isometric to the standard sphere. Hopf gave two proofs of this result (see [9] for details).

This paper deals with the development of an adaptive speed controller for autonomous mobile robot using a fuzzy logic controller.The analysis of performance between a system applying triangular membership and a system using gaussian membership is compared to distinguish their differences. The results have shown that the gaussian membership method has improved the tracking performance for the mobile robot to reach its target. This also suggest the same behavior even when a different mobile robot movements is assigned. This paper considers three, five and seven memberships for both techniques to determine their effectiveness and effects to the system performance. The investigation has leads to the conclusion that the gaussian membership has competently surpassed the triangular membership performances even when the robot has different movements to achieve its target.

In this paper, optimal power allocation is investigated for maximizing the secrecy rate of orthogonal frequency division multiplexing (OFDM) systems under arbitrarily distributed input signals. Considering the discrete inputs are used in practical systems rather than the commonly assumed Gaussian inputs, we focus on secrecy rate maximization under more practical finite discrete constellations in this paper. It is known that the secrecy rate achieved by Guassian distributed inputs is concave with respect to the transmission power. However, we prove that the secrecy rate of finite discrete constellations is non-concave, which makes traditional convex optimization methods not applicable to our problem. To address this non-concave power allocation problem, we propose an efficient power allocation algorithm. Its gap from optimality vanishes asymptotically at the rate \(O(1/\sqrt{N})\), and its complexity grows in order of O(N), where N is the number of sub-carriers. Numerical results are provided to illustrate the benefits and significance of the proposed algorithm.

A commanding model of counterwork simulation system based on value driving decision-making is proposed in this paper. The theoretical foundation of the method is Nash Equilibrium of game theory. This paper analyzes the value driving decision-making model which is based on entity’s maximum benefit and gives examples of value driving decision-making in the Counterwork Simulation System.

In this paper, new results based on the sliding mode control are derived for the global chaos synchronization of identical Coullet chaotic systems (1981). The stability results for the sliding mode control based synchronization schemes derived in this paper are established using Lyapunov stability theory. Since the Lyapunov exponents are not required for these calculations, the sliding mode control method is very effective and convenient to achieve global chaos synchronization of the identical Coullet chaotic systems. Numerical simulations are shown to illustrate the effectiveness of the sliding mode control results derived in this paper for the identical Coullet chaotic systems.

In traditional PF commonly used in electronic engineering, only the present information is used in a single interactive process and the information standing for the small weight of particles will be removed, leading to the problem that the information cannot be made full advantage of. This paper presents a joint SLAM algorithm combined Sparse Extended Information Filter (SEIF) and Particle Filter (PF) aiming to solve the problem occurring in the traditional particle filter algorithms. Information matrixes can keep all history information of poses related to a robot. With the application of Gibbs sampling, new particle set will be re-obtained resulting that posterior distribution can be described better and the state estimation precision is improved. A large amount of Monte-Carlo simulation experiments have proved that the algorithm proposed in this paper has improved the robot’s location precision by approximately 80% over the FastSLAM2.0.

This paper proposes a Dirichlet Process Mixture Model (DPMM) considering relevant topical information for adaptive topic tracking. The method has two characters: 1) It uses DPMM to implement topic tracking. Prior knowledge of known topics is combined in Gibbs sampling for model inference, and correlation between a story and each known topics can be estimated. 2) To alleviate topic excursion problem and topic deviation problem brought by existing adaptive tracking methods, the paper presents a new adaptive learning mechanism, the basic idea of which is to introduce tracking feedback with a reliability metric into the topic tracking procedure and make tracking feedback influence tracing computation under the condition of the reliability metric. The empirical results on TDT3 evaluation data show that the model, without a large scale of in-domain data, can solve topic excursion problem of topic tracking task and topic deviation problem brought by existing adaptive learning mechanisms significantly even with a few on-topic stories.

This paper puts forward a fabric simulation algorithm. The fabric simulation algorithm based on the improved spring-mass model. Firstly, the rigid rod is introduced to replace the structure spring, which is to improve the spring-mass model. Secondly, based on the improved spring-mass model, the fabric model is established. The fabric is composed of equally distributed particles. The particles in the model are force analyzed and the fabric mechanical equations are developed. Finally, the Display Euler equation method is used to solve the numerical values of the space displacements in the particle model. The hyper-elastic problem is perfected in the solving process. The experimental results show that the method in this paper can keep the fabric simulation stable and high efficiency, which realizes the efficient simulation to the fabric.

In this paper, an on-line change detection algorithm for resource allocation in service-oriented systems is presented. The change detection is made basing on a dissimilarity measure between two estimated probability distributions. In our approach we take advantage of the fact that streams of requests in service-oriented systems can be modeled by non-homogenous Poisson processes. Thus, for Bhattacharyya distance measure and Kullback-Leibler divergence analytical expressions can be given. At the end of the paper a simulation study is presented. The aim of the simulation is to demonstrate an effect of applying adaptive approach in resource allocation problem.