Elliptical slot loaded partially segmented circular monopole antenna for super wideband application

This article inspects partially segmented circular monopole with elliptical slot for super wideband applications. Two significant characteristics of proposed antenna design are: (i) partially segmented circular monopole, notch loaded elliptical ground plane along with tapered microstrip line provides super wide bandwidth; (ii) elliptical slot in between the partially segmented circular monopole reduces the lower operating frequency (1.07 GHz–0.96 GHz), which in turn enhance the bandwidth dimension ratio (BDR). For verifying the simulated outcomes, antenna prototype is practically constructed and measured. The proposed antenna design attains frequency range from 0.96 GHz to 10.9 GHz (VSWR < 2) with bandwidth ratio of 11.35:1 and percentage bandwidth of 167.22%. Bandwidth dimension ratio of proposed radiator is 6975.22. Frequency as well as time domain analysis of proposed radiator approves its applicability for super wideband wireless applications.     

Miniaturized wideband dual linearly and circularly polarized printed square slot antenna for multiradio wireless systems

A dual symmetrical coplanar waveguide (CPW)-fed small size wideband printed square slot antenna (SSA) with dual linearly and circularly polarized radiation capability is presented. The antenna is composed using a square slot, two symmetrical orthogonal CPW feed lines connected to horizontal and vertical arm of L-shaped radiator, an embedded parasitic inverted-L strip at the lower left corner of the square ground slot and engraving slots in the ground plane. Circular polarization (CP) is achieved due to two orthogonal CPW feed lines and a common L-shaped radiator. Isolation between ports is improved by engraving slots at the lower left corner of ground plane and embedded parasitic inverted-L strip. The sense of dual-polarization can be changed in pass-band by changing the port excitation. Measured antenna reveals that an 84.4% (4.6 GHz, 3.15–7.75 GHz) −10 dB impedance bandwidth (IBW) and about 33% (2.03 GHz, 5.12–7.15 GHz) 3-dB axial ratio bandwidth (ARBW). Isolation between ports <−16 dB is achieved over usable CP band.     

A novel multi-view learning developed from single-view patterns

The existing multi-view learning (MVL) learns how to process patterns with multiple information sources. In generalization this MVL is proven to have a significant advantage over the usual single-view learning (SVL). However, in most real-world cases we only have single source patterns to which the existing MVL is unable to be directly applied. This paper aims to develop a new MVL technique for single source patterns. To this end, we first reshape the original vector representation of single source patterns into multiple matrix representations. In doing so, we can change the original architecture of a given base classifier into different sub-ones. Each newly generated sub-classifier can classify the patterns represented with the matrix. Here each sub-classifier is taken as one view of the original base classifier. As a result, a set of sub-classifiers with different views are come into being. Then, one joint rather than separated learning process for the multi-view sub-classifiers is developed. In practice, the original base classifier employs the vector-pattern-oriented Ho–Kashyap classifier with regularization learning (called MHKS) as a paradigm which is not limited to MHKS. Thus, the proposed joint multi-view learning is named as MultiV-MHKS. Finally, the feasibility and effectiveness of the proposed MultiV-MHKS is demonstrated by the experimental results on benchmark data sets. More importantly, we have demonstrated that the proposed multi-view approach generally has a tighter generalization risk bound than its single-view one in terms of the Rademacher complexity analysis.     

Detecting node replication attacks in wireless sensor networks: A survey

A wireless sensor network (WSN) consists of a number of tiny, low-cost, and resource-constrained sensor nodes, but is often deployed in unattended and harsh environments to perform various monitoring tasks. As a result, WSNs are susceptible to many application-dependent and application-independent attacks. In this paper we consider a typical threat in the latter category known as the node replication attack, where an adversary prepares her own low-cost sensor nodes and deceives the network into accepting them as legitimate ones. To do so, the adversary only needs to physically capture one node, extract its secret credentials, reproduce the node in large quantity, and then deploy the replicas under her control into the network, possibly at strategic positions, to cripple various WSN applications with little effort. Defending against such node replication attacks has recently become an imperative research topic in sensor network security, and the design issues may involve different and more threatening challenges than detecting typical application-dependent attacks. In this survey, we classify existent detections in the literature, and explore the various proposals in each category. We look into necessary technical details and make certain comparisons, so as to demonstrate their respective contributions as well as limitations. We also present the technical challenges and indicate some possible directions for future research.     

Performance comparison of permanent magnet synchronous motor (PMSM) drive with delay compensated predictive controllers

High efficient current limiting controller is mandatory to obtain ripple-free torque and required speed level in the output of the Permanent Magnet Synchronous Motor (PMSM) drives. In this paper, substantial analysis is taken to control the output torque ripple, to minimize the acoustic noise and also to get the required speed by simulating PMSM with three different investigators such as SVPWM, Model Predictive Control (MPC) and Dead-Beat (DB) Predictive Controller. The designed controllers are tested through the numerical simulations in the MATLAB Simulink Platform and also experimental validation is taken in the laboratory. These predictive investigators are implemented to get good transient response, less torque ripple; reduced harmonics in phase currents and also with delay compensation. The comparison between the simulation and experimental results are presented at the end. The DBP control is suitable for the high performance applications and it is easy to implement in the PMSM drives.     

Fuzzy goal-driven intelligent control for satellite environmental qualification

This paper reports on the application of Fuzzy Reference Gain-Scheduling Control (FRGS) to control a thermal-vacuum unit that emulates space environmental conditions for satellite and space device qualification. FRGS is a variation of fuzzy control that changes the controller gain surface in accordance to distinct operational conditions established by the reference (goal). This system allows to incorporate the experience of human operators by emulating human decision-making and reasoning, with the advantage of adaptation when parameters are adjusted on-line. The controller gain surface is adapted by modifying the shapes of the membership functions according to piecewise constant reference values. While the goal-driven adjustment is accomplished in a feedforward manner, feedback control technique is used to guarantee dynamical response. The experimental response obtained in the application to the real system has shown the effectiveness and flexibility of this control approach for such a nonlinear system.     

Decision making procedure of demand satisfaction and production policy for capacitated production systems

This paper develops a reliability-based decision making procedure for production systems to (i) evaluate the system reliability and (ii) determine the reliable production policy. The production system is represented as a capacitated production network (CPN) for system reliability evaluation, in which the system reliability is defined as the probability of demand satisfaction. The decision making to determine a reliable production policy is based on the derived system reliability. Two layouts are considered in this paper: the first layout is for the CPN with parallel lines; while the second layout is for the CPN with joint lines. Transformation and decomposition techniques are proposed to generate all minimal capacity vectors that workstations should provide to satisfy demand. In terms of the minimal capacity vectors, the system reliability is derived by applying the recursive sum of disjoint products (RSDP) algorithm. A case study in the context of footwear production system is utilized to demonstrate the decision making procedure.     

Output containment control for swarm systems with general linear dynamics: A dynamic output feedback approach

Output containment control problems for high-order linear time-invariant swarm systems under directed interaction topologies are investigated using a dynamic output feedback approach. Firstly, to propel the outputs of followers to converge to the convex hull formed by the outputs of leaders, a dynamic output containment protocol is presented. Then necessary and sufficient conditions for swarm systems to achieve output containment are proposed. To ensure the scalability of the criteria, a sufficient condition which only includes two linear matrix inequality constraints independent of the number of agents is further presented. Moreover, an approach independent of the number of agents is proposed to determine the gain matrices in the dynamic output containment protocols. Finally, numerical simulations are presented to demonstrate theoretical results.     

基于SOPC系统的电子钟设计

采用EDA软件QuartusⅡ中的SOPC Builder构建了一个SOPC系统.并以构建的系统为平台进行电子钟的设计.最后在Altera公司FPGA多媒体开发平台DE2上进行实现.