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The paper put forth presents the design and validation of a novel adaptive, variable gain, sliding mode control (SMC) reaching law, for the purpose of controlling unperturbed nonlinear systems. The novelty of this law stems from its capability to overcome the main limitations involved with conventional SMCs. In contrast to existing reaching laws, the presented law is potentially able to achieve high system performance, reduce the chattering problem significantly, and ensure fast convergence of system trajectories to equilibrium. The designed law integrates the features of both, the exponential reaching law (ERL) and the power rate reaching law (PRL), meanwhile, it overcomes their limitations. Simulation and comparison case studies against ERL and PRL are also carried out with Forearm and Wrist Rehabilitation Robot to validate the effectiveness and advantages of the proposed reaching law scheme (Proposed RL).

Neural networks have shown great potential in many applications like speech recognition, drug discovery, image classification, and object detection. Neural network models are inspired by biological neural networks, but they are optimized to perform machine learning tasks on digital computers. The proposed work explores the possibilities of using living neural networks in vitro as basic computational elements for machine learning applications. A new supervised STDP-based learning algorithm is proposed in this work, which considers neuron engineering constrains. A 74.7% accuracy is achieved on the MNIST benchmark for handwritten digit recognition., Comment: 5 pages, 3 figures, Accepted by ICASSP 2018

In this paper, we propound a solar cell structure that can enhance the absorption in the active layer as compared to the contemporary nano-structured solar cells reported in the literature. We propose a novel multi-layered structure in which a thin film Si semiconductor is sandwiched in between a top layer of annular apertures which support Fabry-Perot Modes and a bottom layer of Ag gratings that increase the active path length. Finite-Difference-Time-Domain simulation method has been performed for the proposed structure to evaluate the generation rate, short-circuit current and open-circuit voltage. The performance parameter values show significant improvement over those of the the conventional thin film solar cells.

In this paper, we propound a command processing mechanism for an autonomous arm manipulator using real-time speech and images. We propose a novel two-stage speech recognition algorithm using two-fold Dynamic Time Warping in each stage. Real-time wake-up word recognition is followed by offline command recognition using k-means. Since high precision is paramount in any control system activation mechanism, a restrictive threshold is set to gain a precision of 1. This alleviates the problem of accidental triggering of the control system. Object recognition and classification is performed by matching features resulting from a local feature detector and descriptor. The algorithm controls an arm manipulator with 5 degrees of freedom.

Detailed performance study of a 10 × 10 cm2 triple GEM detector operated using a gas mixture of 70% Argon and 30% CO 2 has been done with cosmic rays and with 106Ru-Rh β-source. The gain and energy resolution are measured using the X-ray spectrum of the 55Fe source. For the study of the gain uniformity, the active area of the detector is divided into 16 zones and gain is measured in the center of each zone. It is found that the gain variation has an RMS of 6.6%. We also measured the efficiency at the plateau for the 16 zones. The efficiency at the plateau is found to be quite uniform, with an RMS of only 1.9%.

The sensitivity of polycrystalline HgI 2 (poly-HgI 2 ) X-ray detector is determined. A generalized expression for charge carrier transport and absorption-limited sensitivity of X-ray photoconductors is derived by analytically solving the continuity equation for both holes and electrons considering the drift of electrons and holes in the presence of deep traps. Sensitivity is studied as a function of varying applied electric field across the photoconductor for both positive and negative bias under mammographic condition. The theoretical model is fitted to the published results for physical vapor deposited (PVD) poly-HgI 2 mammographic detector. The fitted values of the electron and hole ranges are 1.6896 × 10(−5)cm2V−1 and 5.916 × 10(−6)cm2V−6 respectively. Concentration of deep trap for electrons and holes were found out to be 2.6082 × 1013/cm3 and 3.3806 × 1012/cm3 respectively . Effect of decreasing electron and hole lifetime on sensitivity is studied for varying detector thickness for positive bias under mammmographic condition. Under these conditions, deteriorating hole lifetime has much more impact on sensitivity than deteriorating electron lifetime. Presence of an optimum detector thickness has been found at low hole lifetime

Propeller wake wash has been used effectively for ice management operations for years. The main uses of propeller wake wash include clearing pack ice and broken ice from protected installations and shipping channels. A numerical model of a propeller wake has been developed to simulate the effects of the wake, or jet, on ice pieces floating on the water surface. The propeller wake is modeled using the theory of horizontal round jets as well as empirical equations derived from previous experiments. The modification of the propeller jet due to the free surface is modeled using experimental results for round jets. A dynamic model of ice piece motion is used to simulate the action of the jet on ice pieces. Model predictions are compared to experimental results of pack ice subjected to propeller wake wash. The analysis shows that the model can be used to simulate the clearing of pack ice. The model was subsequently incorporated in a real time simulator to assess its performance in 3D rendered virtual environments., OCEANS 2014, September 14-19, 2014, St. John's, NL, Canada

This paper presents a novel approach to accessing information stored in legacy relational databases (RDB), based on Semantic Web (SW) and multiagent systems (MAS) technologies. Its purpose is to provide the users of enterprise decision-support systems with direct, flexible, and customized access to information, through high-level semantic queries, without the need to modify the underlying legacy databases. This is effected through a distributed architecture, based on agent-oriented intelligent middleware, consisting of servers that contain databases and clients that provide customized access to users. In a server, the meaning of the database structure is captured in the reference ontology, which is exported to clients. In a client, the meaning of concepts specific to a user is captured in the custom ontology of that user, as an overlay that relies on the imported reference ontologies. These system ontologies are built gradually, within the system itself, in a process that automatically generates the basic structures from RDB schemas and incrementally enhances them to full ontologies through human-agent interactions. The approach relies on agents endowed with meta-ontology that assist human actors in the ontology-building process. A part of their role is to find, identify, reference, import, display, and apply relevant knowledge available on the Semantic Web. The development of ontologies in turn permits further delegation of operational tasks to agents. The approach is expected to become increasingly effective with the advancement of the SW infrastructure. The paper explains the conceptual basis of the approach, outlines the distributed system architecture, and focusses on the server functionality, including the development of reference ontology.

The goal of this project is to design a user interface for the videophone system to enable real-time video chat. The system includes voice and 3D talking heads and able to communicate using very low bandwidth because no video data are transmitted through network. Instead of video, facial expressions of speakers are transmitted along with voice in the real time. At the other end, talking head will show those facial expressions and will render the voice. The facial structure of the talking head will resemble the speaker's face.

Over the past 25 years, line-start fractional horsepower interior permanent magnet synchronous motors have expanded their presence in the domestic marketplace from few specialized niche markets in high efficiency machine tools, household appliances, small utility motors and servo drives to mass-produced applications. A closer examination reveals that several different knowledge-based technological advancements and market forces as well as consumer demand for high efficiency requirements have combined to accelerate the development of the improved new small energy efficient motors. The purpose of this paper is to provide a broad explanation of the various factors that lead to the current state-of-the-art of the single phase interior permanent motor drive technology. A unified analysis of single phase interior permanent magnet motor that permits the determination of the steady state, dynamic and transient performances under different operating conditions is presented. The mathematical model is based on both d-q axis theory and finite element analysis. It leads to more accurate numerical results and meets the engineering requirements more satisfactorily than any other methods. Finally, some concluding comments and remarks are provided for manufacturing and future research trends of line-start energy efficient permanent magnet synchronous motors.

This paper introduces the design and performance analysis of an interior permanent magnet generator (IPMG) for applications in low speed wind turbine systems. The developed design is based on optimizing the geometry of double-layered permanent magnets (PMs), which are buried in the rotor body of an IPMG. The geometry of the double-layered permanent magnets is optimized and simulated using the 2-D finite element analysis method (FEA). The optimization of the PMs is established based on the induced electromotive force (EMF), harmonic contents of the stator current and torque ripples at low speeds. The optimization shows that the π-shape double-layered permanent magnets geometry is capable of inducing an EMF with the high magnitude and low harmonic contents, along with producing stator currents with the low harmonic contents and minimum torque ripples.

In this paper we present the Free Form Technical Indicator (FFTI), a new technical analysis tool developed for aiding the research of technical indicators. FFTI provides a flexible and easy to use yet powerful platform to create and test new technical indicators for analyzing price and volume movements in a stock market. Contemporary technical analysis tools offer many built in indicators. Implementing a conceptually new indicator in those tools requires customization of the software and programming involvement. But FFTI offers an indicator creation method that is straight forward, easy to learn and at the same time exceptionally expressive without the need of any programming or customization. In this work, we present a detailed description of FFTIs indicator creation platform with demonstration of its power by showing a number of well-known indicators written in FFTIs terminology. FFTI is intended for researcher as well as share market investors. It is web-based, free and open source. FFTI has a simple programming interface for future extensions of its terminology and capability with easily pluggable modules.