Steganalysis by subtractive pixel adjacency matrix and dimensionality reduction

Subtractive pixel adjacency matrix(SPAM)features,introduced by Pevn′y et al.as a type of Markov chain features,are widely used for blind steganalysis in the spatial domain.In this paper,we present three improvements to SPAM as follows:1)new features based on parallel subtractive pixels are added to the SPAM features,which only refer to collinear subtractive pixels;2)features are extracted not only from the spatial image,but also from its grayscale-inverted image,making the feature matrices symmetrical and reducing their dimensionality by about half;and 3)a new kind of adjacency matrix is used,thereby reducing about 3/4 of the dimensionality of the features.Experimental results show that these methods for dimensionality reduction are very effective and that the proposed features outperform SPAM.     

Generating Web Traffic Based on User Behavioral Model

Generating web traffic is of great importance to analyze performance of new designed network, test new equipment, and verify new protocols, etc.. However, most existing traffic generation systems tend to simulate the overall characteristics of network traffic, while neglecting of the behavior of the individual users. Nevertheless, in principle, the emerged characteristics of overall traffic originate from the aggregation of individual users＇ access behavior. In this paper, we propose an innovative web traffic generating method based on user browsing behavior. Our method simulates the real users＇ accessing behavior, and visits the real web servers. Then, we design and develop a web traffic generating system. Because our system accesses the real websites, it can produce almost the real network traffic. The test results show that the traffic generated by our system has characteristics of burstiness and self-similarity, which are widely found and characterized in many real networks. In addition, our system can better reflect real user＇s web browsing behavior.     

A Multi-Detector Security Architecture with Local Feature-Level Fusion for Multimodal Biometrics

The hierarchical identification model with multiple detectors is an innovative approach for biometric systems design which improves the identification accuracy while ensuring the computational complexity reduction. This complexity reduction provides additional advantages in terms of execution time and recognition accuracy. The model is different from the actual solutions for biometric data classification because it essentially uses a special kind of classifiers （detectors） and the identification decision is issued in a hierarchical way according to the users importance; this makes it suitable for various security requirements applications （users with different authorization levels）. The model includes a local feature-level fusion for each of the integrated biometrics. The paper defines and explains the multi-detector security architecture with its basic functions. The achieved experimental results are discussed to reveal the proposed method advantages and further potential enhancements for particular use cases.     

Performance Evaluation of a Markovian Policy for Macro/Femto User Allocation Considering Aspects of QoS,QoE and Energy Efficiency

The advancement of wireless networks offers mobile users a diversity connectivity options, but the choice of the best connection should consider classics QoS aspects and, with increasing multimedia applications, should also consider QoE metrics. Another important parameter to choose the best connection is the energy efficiency by reducing the battery consumption of the devices and reducing CO2 emissions （green network）. This paper validates a Markovian policy for distribution of user load balancing in femtocell/macrocell networks considering QoS/QoE and energy consumption providing quality for multimedia applications. The results obtained by simulation proved the benefits.     

Mobile Advertising Service Based on 4R Mode

As people own more and more various smart devices, providing advertising to those devices has become a lucrative platform for different advertisement providers. However, the way advertisements are delivered to customers＇ smart devices needs to be improved. Many variables determine the most effective way to provide the mobile advertisement to the end-user. So a mobile advertising service based on the 4R model is needed The correct time, location, contents and target device to make the mobile advertising interesting and also useful for the customers. need to be determined in order for the advertisement to be contextual and the most effective. The 4R model is beneficial for the advertisers and the end-users alike.     

Consideration of Persuasive Technology on Users Acceptance of E-Commerce： Exploring Perceived Persuasiveness

Persuasive technologies, used within in the domain of interactive technology, are used broadly in social contexts to encourage customers towards positive behavior change. In the context of E-commerce, persuasive technologies have already been extensively applied in the area of marketing to enhancing system credibility, however, the issue of ＂persuasiveness＂, and its role on positive user acceptance of technology, has not been investigated in the technology acceptance literature. This paper reviews theories and models of users＇ acceptance and use in relation with persuasive technology, and identifies their limitation when considering the impact of persuasive technology on users＇ acceptance of technology; thus justifying a need to add consideration of ＂perceived persuasiveness＂. We conclude by identifying variables associated with perceived persuasiveness, and suggest key research directions for future research.     

一类分层非结构化P2P系统的随机切换模型

对于一类利用集中式构架和分布式构架各自优点的分层非结构化P2P系统,通过定义一种Markov切换空间模型来描述其动态分组切换行为.在Markov决策过程理论的基础上,给出了关于性能指标的策略迭代和在线策略迭代算法,并通过实例仿真说明该方法的优越性.     

基于主题隐马尔科夫模型的人体异常行为识别

针对基于监控视频的人体异常行为识别问题,提出了基于主题隐马尔科夫模型的人体异常行为识别方法,即通过无任何人工标注的视频训练集自动学习人体行为模型,并能够应用学到的人体行为模型实时检测异常行为和识别正常行为。这一方法主要围绕"低层视频表示-中层语义行为建模-高层语义分类"3个方面进行:1)基于时-空间兴趣点构建了一种紧凑的和有效的视频表示方法。2)提出一种新颖的语义主题模型(Topic Model,TM)——主题隐马尔科夫模型(Topic Hidden Markov Model,THMM),它能够自然地分组视频中检测到的人体行为。主题隐马尔科夫模型基于已有的马尔科夫模型和主题模型构造,不但聚类运动词汇成简单动作,而且聚类简单动作成全局行为,同时建模了行为时间上的相关性。THMM是一个4层贝叶斯主题模型,它将视频序列建模为行为的马尔科夫链,同时行为是视频序列中某些视频剪辑(Clip)的概率分布;将视频剪辑建模为动作的随机组合,同时动作是视频剪辑中运动词汇的概率分布。克服了传统隐马尔科夫模型和主题模型在人体复杂行为建模过程中精度、鲁棒性和计算效率上的不足。3)提出运行时累积的异常性测度及其在线异常行为检测方法和基于在线似然比检验(Likelihood Ratio Test,LRT)的实时正常行为分类方法,从而克服了实时行为识别过程中由于缺乏充分的视觉证据而引发的行为类型歧义,能完较好地完成监控场景中实时异常行为检测和在线正常行为识别的任务。取自实际监控场景的实验数据集上的实验结果证明了本方法的有效性。     

Semi-supervised classification based on Markov Random Field and Robust Error Function

We focus on semi-supervised classifier, where a decision rule is to be learned from labeled and unlabeled data. A model to semi-supervised classification is proposed to overcome the problem induced by mislabeled samples. A new energy function based on robust error function is used in Markov Random Field. Also two algorithms based on iterative condition mode and markov chain monte carlo respectively are designed to infer the label of both labeled and unlabeled samples. Our experiments demonstrate that the proposed method is efficient for real-world dataset.     

Asymptotic unbounded root loci--Formulas and computation

We study the asymptotic behavior of the dosed loop eigenvalues (root loci) of a strictly proper linear time-invariant control system as loop gain goes toinfty. The formulas are stated in terms of the eigenvalues of nested restricted linear maps of the formA(mod S_{2})|_{S_{1}}where S1and S2are subspaces of complementary dimension. Additional geometrical insight into the formulas is obtained by mechanizing the formulas using orthogonal projections. Our method and formulas are useful in other asymptotic calculations as well, e.g., hierarchical multiple-time scales aggregation of Markov chains with some infrequent transitions.     

Performance Evaluation of Antenna Receive Diversity in SlMO-OFDM System over Rayleigh Fading Channel

This paper represents a comparative performance evaluation of different diversity combining techniques for a SIMO-OFDM （single-input-multiple-output orthogonal frequency division multiplexing） system over Rayleigh fading channel. OFDM is a key technique for achieving high data rates and spectral efficiency requirements for wireless communication systems. But in scattering environment, the system performances are severely degraded by the effects of multipath fading and inter-symbol interference. In wireless communication systems, antenna diversity is an important technique to combat multipath fading in order to improve the system performance and increase the channel capacity. In this paper, the performance of different diversity combining techniques-SC （selection combining）, EGC （equal gain combining） and MRC （maximal ratio combining） has been analyzed and compared in terms of SNR （signal to noise ratio） and BER （bit error rate） probability. The simulation results show that the maximal ratio combining technique provides maximum performance improvement relative to all other combining schemes by maximizing the SNR of SIMO-OFDM system at the combiner output. The analytic expressions of error probability and effective bit energy to noise ratio correlated with BPSK （binary phase shift keying） modulation have been derived and formulated for N-branch SC, EGC and MRC schemes. The BER characteristics for all three combining techniques are simulated in MATLAB （matrix laboratory） tool box for varying bit energy to noise ratio. Our results also derives that SNR can be improved if the number of receiving antenna is increased, which in turn reduces BER over a Rayleigh fading channel.     

Normalized Efficient Routing Protocol for WSN

WSNs （wireless sensor networks） consist of thousands of tiny nodes having the capability of sensing, computation, and wireless communications. Unfortunately these devices are limited energy devices, that is means we must save energy as much as possible, to increase network life time as long as possible. In this paper we introduce NEER--normalized energy efficient routing protocol that increases network life time through switching between AODV protocol that depends on request-reply routing, and MRPC that depends on residual battery in routing.     

From IP to Start-up： Building a Robust Life Science Incubator

An incubator is an organization that supports new ventures to grow and survive during the early stages. Mainly dedicated to information technology, life science may appear to be the next hot spot for incubators. Are there stabilized good practices？ Are the business models in information technology and in life science comparable when it goes to start-ups＇ incubation？ Leveraging our experience as practitioner in this field and using an inductive methodology, this paper tends to propose simple principles to help build robust incubators in life science, and to contribute to disseminate an entrepreneurial approach through an industry still dominated by blue chips.     

Real-time control of human actions using inertial sensors

Our study proposes a new local model to accurately control an avatar using six inertial sensors in real-time.Creating such a system to assist interactive control of a full-body avatar is challenging because control signals from our performance interfaces are usually inadequate to completely determine the whole body movement of human actors.We use a pre-captured motion database to construct a group of local regression models,which are used along with the control signals to synthesize whole body human movement.By synthesizing a variety of human movements based on actors’control in real-time,this study verifies the effectiveness of the proposed system.Compared with the previous models,our proposed model can synthesize more accurate results.Our system is suitable for common use because it is much cheaper than commercial motion capture systems.     

Towards estimating computer users＇ mood from interaction behaviour with keyboard and mouse

The purpose of this exploratory research was to study the relationship between the mood of computer users and their use of keyboard and mouse to examine the possibility of creating a generic or individualized mood measure. To examine this, a field study （n = 26） and a controlled study （n = 16） were conducted. In the field study, interaction data and self-reported mood measurements were collected during normal PC use over several days. In the controlled study, participants worked on a programming task while listening to high or low arousing background music. Besides subjective mood measurement, galvanic skin response （GSR） data was also collected. Results found no generic relationship between the interaction data and the mood data. However, the re- suits of the studies found significant average correlations be- tween mood measurement and personalized regression models based on keyboard and mouse interaction data. Together the results suggest that individualized mood prediction is pos- sible from interaction behaviour with keyboard and mouse.     

Counterworking the Operation Disturbance of a Radiators Structure due to External Actions

The operation of a complicated radiators structure creating a required field in a given area is disturbed often due to different external actions. As an example, the impact of metallic objects approaching off to an antenna system with minimal irradiation on user＇s body is analyzed. In this case, the zone itself, where the area of a weak field （a dark spot） is created, is generally not approachable for sensors installation. In order to counteract the disturbance of the system operation due to presence of different metallic objects in close proximity to the radiators, two methods based on two information sources are studied. These information sources are antennas driving currents and fields at a predetermined point outside the given area. As an example, the antenna system used in the compensation method for reducing human＇s body irradiation, to which a metal object approaches, is analyzed. The conditions of severe external actions are considered： a great metal body and a small distance from this body to the dark spot. It is shown that under these conditions of severe external actions the second method based on the field values measuring demonstrates a higher efficiency. A block scheme for structure of an automatic adjustment is suggested. The considered problem is a common one, and developers of radio circuits are faced with them constantly.     

A 2.4 GHz low power CMOS transceiver for LR-WPAN applications

A 2.4 GHz low power transceiver for low-rate wireless personal area network(LR-WPAN)applications is presented.The optimized low-IF receiver consists of a novel current reuse RF front-end with an inductor-less-load balun LNA and quadrature mixer,and an adaptive analog baseband to reduce power and area.It achieves-94 dBm of sensitivity,-9 dBm of IIP3 and 28 dBc of image rejection.The phase-locked loop based direct phase modulated transmitter is proposed to reduce power and deliver a+3 dBm output power.The phase noise of the low power frequency synthesizer with current reuse stacked LC-VCO achieves-107.8 dBc/Hz at 1 MHz offset.An ultra-low power nonvolatile memory is used to store configuration data and save power.The chip is implemented in a 0.18μm CMOS process,and the area is less than 2.8 mm2.The transceiver consumes only 10.98 mW in the receiving mode and 13.32 mW in the transmitting mode.     

Remote-Controlled Ambidextrous Robot Hand Concept

In the development of robotic limbs, the side of members is of importance to define the shape of artificial limbs and the range of movements. It is mainly significant tbr biomedical applications concerning patients suffering arms or legs injuries, fn this paper, the concept of an ambidextrous design lbr robot hands is introduced. The fingers can curl in one xvay or another, to imitate either a right hand or a left hand. The advantages and inconveniences of different models have been investigated to optimise the range and the maximum force applied by fingers. Besides, a remote control interthce is integrated to the system, allowing both to send comrnands through internet and to display a video streaming of the ambidextrous hand as feedback. Therefore, a robotic prosthesis could be used for the first time in telerehabilitation. The main application areas targeted are physiotherapy alter strokes or management of phantom pains/br amputees by/earning to control the ambidextrous hand. A client application is also accessible on Facehook social network, making the robotic limb easily reachable for the patients. Additionally the ambidextrous hand can be used tbr robotics research as well as artistic performances.     

Wideband Rectangular and Circular Microstrip Antennas Loaded with U-Shaped Slot

In this paper, a dual frequency resonance antenna is analysed by introducing U-shaped slot in a rectangular and circular patch, the results in terms of return loss, input impedance and radiation pattern are given. It is observed that various antenna parameters are obtained as a function of frequency for different value of slot length and width; it is easy to adjust the upper and the lower band by varying these different antenna parameters. The coaxial feed is used to excite the patch antenna. All the theoretical results using Matlab are compared with the simulated results obtained from Ansoft HFSS which are in close agreement. Furthermore, comparative study between our results and those available in the literature is done and showed to be in good agreement.     

Optimal resource allocation for transmission diversity in multi-radio access networks： a coevolutionary genetic algorithm approach

The next generation wireless communication systems aim at supporting enhanced diversified network access and data transmission abilities via the cooperative integration and unified management of various radio access technologies(RATs).The resource allocation is the core component leading the network system and mobile terminals to the service robustness and performance maximization.In this paper,a numeric optimization model for optimizing terminals’transmission power and allocated RAT bandwidth for maximizing system capacity is proposed with the focal consideration of the multi-radio transmission diversity for parallel transmission through multiple links from diferent RATs,and diferent terminal characteristics on RAT supports.Also,we design a centralized and periodic scheduling algorithm including an improved coevolutionary genetic algorithm for efciently solving the optimization problem.Simulation results demonstrate that our propose algorithm can distinctly enhance the system performance and improve the computational efciency.