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With the advent of technology, there has been a rapid increase in data acquisition. Among the several types of data gathered, interpreting multimedia data by a machine without human intervention is a challenge. Extracting meaningful content from videos will help provide better solutions in various domains. Banking on processing the videos as our rudimentary concept, this paper intends to detect the expressiveness of an individual. Many traditional approaches exist to address this situation, however Deep learning is used in this work to achieve the goal. LSTM (Long Short Term Memory) is our selected implementation construct. For training the network MIT Affectiva dataset has been chosen, which comprises of videos of individuals responding to Superbowl commercials. Extending this network, two front ends for testing the video sample are provided. One is a web page for uploading the videos and displaying the results and the other is an IoT device. This device records the video of an individual's response and sends it to the processing server. The responses of individuals towards a particular commercial are recorded and the system is tested on it. The results obtained are examined and the scope for various interpretations are shown. The expressiveness detected becomes a pivotal feedback for the makers of commercials, paving the way for their improvement.

The Filter Bank Multi-Carrier (FBMC) with Offset Quadrature Amplitude Modulation (OQAM) has some appealing properties that make it to gain currency as one of the alternatives to OFDM for next generation broadband wireless access systems. Albeit, being a multicarrier modulation (MCM) technique, it is prone to non-linear (NL) effects of power amplifier (PA). As energy efficiency radio communications is the need of hour, it is essential to mitigate NL effects. This paper focuses on PA linearization, especially digital predistortion (DPD). It is imperative that, any new DPD technique suggested for FBMC-OQAM, need to take into account its overlapping signal structure. A novel DPD technique, termed as overlapped recursive error correction has been proposed in this paper for linearization of non-linearly amplified FBMC-OQAM signals.

The coexistence of broadband systems with currently deployed Professional Mobile Radio (PMR) communication systems like Public Protection and Disaster Relief (PPDR) has gained much deserved attention. In the recent literature, it has been suggested that LTE-like FBMC-OQAM system working on linear devices can coexist in PMR band, while conventional OFDM-based LTE system fails. When we take into account, the RF impairments in radio communication systems; it is inevitable to consider the non-linear nature of High Power Amplifiers (HPAs), as they add severe hindrance in this aspect. In this paper, we address this issue and show that LTE-like FBMC-OQAM system working on non-linear devices can still co-exist with PMR/PPDR systems, when suitable peak-to-average power ratio (PAPR) is applied.

Filter-bank multi-carrier (FBMC) with offset-quadrature amplitude modulation (OQAM) is being seriously considered for 5th generation radio access technology. In this paper, we investigate the problem of peak-to-average power ratio (PAPR) reduction of FBMC-OQAM signals. We propose a novel scheme based on tone reservation (TR) scheme by considering the overlapping nature of FBMC-OQAM symbols. Any TR scheme uses the reserved tones to design a peak cancellation signal that reduces the PAPR. Simulation results indicate that the FBMC-OQAM with the proposed dispersive TR (DTR) scheme is not only efficient in reducing the PAPR but also closely lagging OFDM with classical TR scheme.

The Filter bank multi-carrier (FBMC) with offset-quadrature amplitude modulation (OQAM) gained lot of attention recently. Both orthogonal frequency division multiplexing (OFDM) and FBMC-OQAM suffer from high peak-to-average power ratio (PAPR). The classical PAPR reduction schemes suggested for OFDM signals cannot be directly applied on the OFDM-OQM, due to the overlapping structure. In this paper we investigate the problem of PAPR reduction in FBMC-OQAM systems and a trellis-based selected mapping (TSLM) scheme with dynamic programming (DP) has been proposed, which probes for optimal phase rotation vectors. With selected mapping (SLM) scheme, multiple patterns of the modulated signal are generated. Theoretical and numerical analyses indicate that TSLM offer better PAPR reduction performance as compared to symbol-by-symbol approach. Simulation results show that performance of FBMC-OQAM system with this method is not only superior to any scheme based on symbol-by-symbol approach, but also outperforms that of the OFDM with classical SLM scheme. It has also been shown that this result holds for different prototype filter impulse responses that are more or less localized in time or frequency.

Relevance of Filter Bank Multi-Carrier (FBMC) systems along with Offset Quadrature Amplitude Modulation (OQAM) for 5G Radio Access Technology (RAT) cannot be ruled out. FBMC-OQAM modulation technique has many attractive features over OFDM that make it more appealing to be the radio waveform in 5G. However, being a multi-carrier modulation technique, it has high PAPR and prone to spectral regrowth in the presence of a non-linear high power amplifier (HPA), which is a vital component in contemporary modern communication systems. This spectral regrowth indicate that the excellent frequency localization property of the FBMC-OQAM signals no longer holds in the presence of a non-linear HPA. So, there is a dire need to predict the extant of spectral regrowth induced by the HPA non-linearities. With cumulants, it is possible to predict the power spectral density (PSD) of the HPA output. Prediction of spectral regrowth in the case of OFDM systems was already done and in this paper it is extended to FBMC based systems. HPA of Salehs model is used for simulations but prediction can be done for any measured or modeled HPA after polynomial fitting of its AM/AM and AM/PM distortion characteristics.

The Filter Bank Multi-Carrier (FBMC) based systems are being seriously considered for 5G Radio Access Technology (RAT). As FBMC-OQAM is a multi-carrier technique, it suffers from the high Peak-to-Average Power Ratio (PAPR) and directly applying the PAPR reduction schemes proposed for OFDM to FBMC-OQAM turns out to be ineffective, due to its overlapping structure. In this paper, a scheme named as Dispersive Selective Mapping (DSLM) is proposed, which is an extended and generalized version of Overlapped Selective Mapping (OSLM). Simulation results show that performance of this method is very closely trailing to that of OFDM.

One major challenge is to develop high performance light weight end effectors for various applications in fields like medical, space, aerospace and deep water explorations. For this reason today new robots able to guarantee more dexterity and workspace are under study. Smart actuators like shape memory alloys (SMA) can fill this gap due to their very high energy density (power to weight ratio). They share many common aspects with traditional robotic assemblies such as positioning of manipulators, velocity, jerk and force control, tactile feedback, task planning, collision avoidance, grasping, part orientation, etc. End-effectors like grippers utilizing SMAs as direct drive actuating elements can find vast applications in industrial automation, assembling parts, semiconductor industries, non-invasive medical surgeries and processing of biological objects. This article presents a gripper actuated by SMA wire. The mechanical structure of the gripper includes a pair of jaws-one fixed and other movable, a SMA wire for actuation and a biasing torsion spring for the strain recovery in SMA wire. An experimental setup of the SMA gripper is established. The SMA actuator is heated by the electric current. A noncontact laser displacement sensor is engaged to measure the position of the movable jaw. In order to control the position of the devised gripper, a model of the gripper is estimated from open loop experimental data using system identification technique. Finally, Sliding Mode Control (SMC) technique is designed and compiled to track various stationary and variable (dynamic) trajectories to suit applications that can manipulate objects of varied dimensions. Experimental results show that the gripper is able to track the position rapidly and precisely.

This paper demonstrates the self-sensing behaviour of Shape Memory Alloys (SMAs) in controlling an SMA wire actuated gripper. High power-to-weight ratio, large recovery strain, low driving voltages and direct drive capability of SMA attracted considerable research attention. To make SMA more applicable to small scale robotic manipulations, its motion control using accurate self-sensing is a best alternative. The self-sensing algorithm uses sliding mode control (SMC) in this work. A self-sensing model is built by measuring the electrical resistance of SMA wire. The polyfit model facilitates to replace additional sensor and electronics for position feedback. Demonstration of the advantages gained from using self-sensing polyfit model is evident through stationary trajectory tracking control experiment. The method is accurate and precise in tracking, providing a scope for sensorless control by simplifying the control system. With the merits shown, we expect this technique can be utilized for SMA actuators in meso to micro scale applications.

Shape memory alloys (SMA) are the class of stimulus responsive materials which are used as actuators because of the ability in recovering their predetermined shape when subjected to an appropriate thermal procedure. This shape recovery introduces a mechanical work that can be used to produce linear or rotational movements of a modular actuator. This work presents the investigation of control algorithms for position control of a shape memory alloy actuated gripper. The transfer function model of the SMA fiber actuator is determined from the experimental open loop response. Model based proportional integral (PI), pulse width pulse amplitude modulated proportional integral (PI-PWPAM) and internal model sliding mode controller (IM-SMC) controllers are designed. The performance of these controllers is simulated for position control. The results demonstrate that the IM-SMC performs well in tracking the desired response and provides faster response.