•Co-LSTM is a classifier for sentiment analysis of social media reviews.•Co-LSTM leverages the best features of both convolutional neural network and Long short-term memory in order to model the ...classifier.•Word embedding model has been applied in constructing vocabulary dictionary.•Co-LSTM is compared with other machine learning and deep learning models.
Analysis of consumer reviews posted on social media is found to be essential for several business applications. Consumer reviews posted in social media are increasing at an exponential rate both in terms of number and relevance, which leads to big data. In this paper, a hybrid approach of two deep learning architectures namely Convolutional Neural Network (CNN) and Long Short Term Memory (LSTM) (RNN with memory) is suggested for sentiment classification of reviews posted at diverse domains. Deep convolutional networks have been highly effective in local feature selection, while recurrent networks (LSTM) often yield good results in the sequential analysis of a long text. The proposed Co-LSTM model is mainly aimed at two objectives in sentiment analysis. First, it is highly adaptable in examining big social data, keeping scalability in mind, and secondly, unlike the conventional machine learning approaches, it is free from any particular domain. The experiment has been carried out on four review datasets from diverse domains to train the model which can handle all kinds of dependencies that usually arises in a post. The experimental results show that the proposed ensemble model outperforms other machine learning approaches in terms of accuracy and other parameters.
Analyzing the structure of a social network helps in gaining insights into interactions and relationships among users while revealing the patterns of their online behavior. Network centrality is a ...metric of importance of a network node in a network, which allows revealing the structural patterns and morphology of networks. We propose a distributed computing approach for the calculation of network centrality value for each user using the MapReduce approach in the Hadoop platform, which allows faster and more efficient computation as compared to the conventional implementation. A distributed approach is scalable and helps in efficient computations of large-scale datasets, such as social network data. The proposed approach improves the calculation performance of degree centrality by 39.8%, closeness centrality by 40.7% and eigenvalue centrality by 41.1% using a Twitter dataset.
A microstrip line feed modified Sierpinski square fractal antenna for ultra-wide band (UWB) with band notch characteristics is presented. UWB operation (3.1–10.6 GHz) is achieved by increasing the ...numbers of iteration and rectangular grooved ground plane. The band rejection characteristic is realised by a ∩ -slot in the feed line. The proposed antenna has a volume 34 × 34 × 1.6 mm3 with a square shape structure and shows omnidirectional radiation patterns. The measurement results indicate that the antenna offers UWB operation and a notch at 5.5 GHz (5–6 GHz) for a reflection coefficient below −10 dB which covers the wireless local area network band. Acceptable agreement is obtained between the simulated and measured antenna performance parameters. These characteristics demonstrate that the proposed antenna is an attractive candidate for UWB applications.
Radio frequency identification (RFID) is a quickly growing innovative wireless data capturing technology for automatic identification, product tracing, security investigation, automatic toll fee, ...vehicle tracking, and e-Health. Wearable sensing technology and on-body structures have achieved pervasive responses due to their fabulous potential in the Internet of Things (IoT), healthcare, and smart homes. Inexpensive chipless RFID tags for on-body sensing are the upcoming research for such wearable devices. Its sensing skill offers the unified real-time monitoring of vital signs. This paper reviews various chipless passive RFID tag sensors for wearable applications. The main goal of this research work is to study the basics of chipless RFID sensors and their working principles. Further, chipped RFID sensors are very costly for mass implementation. Hence, chipless tag sensors have grown into a cost-effective and maintenance-free substitute, fulfilling the requirements of the society for the emergent technologies, where lots of these sensors can be used. Understanding the importance in emerging applications, essential materials needed for different sensors, basic circuit models for chipped and chipless sensors, and challenges with limitation of recent chipless RFID sensors are also discussed in this article.
3,5-Diphenyl Isoxazole derivatives, constituting an important family of five-membered heterocycles with one oxygen atom and one nitrogen atom at adjacent positions is of immense importance because of ...its wide spectrum of biological activities and therapeutic potential. It is, therefore, of prime importance that the development of new synthetic strategies and designing of new isoxazole derivatives should be based on the most recent knowledge emerging from the latest research. This review is an endeavour to highlight the progress in the chemistry and biological activity of 3,5-Diphenyl isoxazole derivativesto the medicinal chemists for the development of clinically viable drugs using this information. One series of total 10 (3,5-Diphenyl Isoxazole) derivatives were synthesized but Compound A, Compound H & Compound I were designed elemental analysis and evaluated for antifungal and antioxidant activity.
In a social network, small or large communities within the network play a major role in deciding the functionalities of the network. Despite of diverse definitions, communities in the network may be ...defined as the group of nodes that are more densely connected as compared to nodes outside the group. Revealing such hidden communities is one of the challenging research problems. A real world social network follows small world phenomena, which indicates that any two social entities can be reachable in a small number of steps. In this paper, nodes are mapped into communities based on the random walk in the network. However, uncovering communities in large-scale networks is a challenging task due to its unprecedented growth in the size of social networks. A good number of community detection algorithms based on random walk exist in literature. In addition, when large-scale social networks are being considered, these algorithms are observed to take considerably longer time. In this work, with an objective to improve the efficiency of algorithms, parallel programming framework like Map-Reduce has been considered for uncovering the hidden communities in social network. The proposed approach has been compared with some standard existing community detection algorithms for both synthetic and real-world datasets in order to examine its performance, and it is observed that the proposed algorithm is more efficient than the existing ones.
Currently, there is a great demand for low-cost solutions in connected healthcare and real-time wireless patient monitoring remotely. Radio frequency identification (RFID) is a rapidly emerging ...wireless technique for remote data capturing utilized in multifarious applications such as healthcare, automated identification, object tracking, security and authentication, food packaging, and automobile tracking. The projected cost of conventional RFID technology hampers it from being used widely. Chipless RFID sensors with the Internet of Things (IoT) technology have the full potential to meet the requirements of the growing demand. With the development of present technologies, the IoT-based solutions are no longer a challenging vision that offers various potential benefits to today's world, especially healthcare which is an encouraging field of IoT. The design and development of chipless sensors for health monitoring have gathered the attention of the researchers in last few years. This article provides a comprehensive review of chipless RFID sensors that play a vital role in cost-effective healthcare applications. The working principle of a chipless sensing system, fabrication techniques, and classifications of different chipless RFID sensors along with the smart sensing materials are highlighted. This article throws light on numerous chipless RFID sensors for IoT-based healthcare applications including their challenges and future directions. In addition to that, a comparison table of recent developments in the area of IoT-based healthcare is prepared.
A log-periodic dielectric resonator antenna for possible wideband operation is considered. The proposed design consists of seven dielectric resonators (DRs) of rectangular cross-sections using a ...low-cost Teflon-based dielectric material with low permittivity. It has a multilayer configuration, where the DRs and feeding line are located at different layers. For ease of fabrication, the radiators are excited by an overlaid microstrip feed line on the first layer. Different characteristics such as S-parameters, gain, input impedance and radiation patterns of the proposed design are studied. The fabricated prototype exhibits a gain of 6 dBi (or better) over a wideband of 6.5–11.3 GHz with |S11| less than − 10 dB. The results from the simulation are found to closely follow those of the fabricated prototype.
Summary Reconfigurable fractal antenna (RFA) design is always necessary for the continued development of wireless communication systems as the antenna is playing a vital part in device performance. ...The need for efficient radiators that are compact, low‐profile, inexpensive, and low weight has attracted scientists for their research works. As a result, numerous ideas were put forward by the researchers to attempt to resolve these problems by utilizing various kinds of fractal and reconfigurable antennas as well as their combinations. However, it is challenging to have a clear and transparent review of the various works with a large variety of solutions and their uniqueness. The advanced RFA design for wireless applications is reviewed in this study together with its most recent and pertinent counterparts. In Koch RFA, bandwidths enable selective bands spanning 1–6 GHz frequency range. Further, in band RFA design, the overall bandwidth ranges from 1.45 to 4.52 GHz (103%) with low gain; on the other hand, the crescent RFA achieves 5.67 dBi peak gain. Furthermore, in polarization RFA, the ARBWs are 17.61% (2.2–2.62 GHz) and 8.69% (2.91–3.18 GHz). The Hilbert RFA operates at 0.9 and 2.45 GHz with gains of 3.1 and 7 dBi, respectively. This article investigates a comprehensive review of the requirements for RFAs for wireless applications. Furthermore, a comparative study on different reconfigurability with switching techniques, fractal geometries, various RFA design approaches to enhance device performance, and their significance is discussed. Existing research challenges and future directions are also discussed as part of this article.
The present era of digitization is looking forward to updating the manual system with automation. The chipless Radio Frequency Identification (RFID), a well-known wireless technology, eliminates the ...hurdle of human intervention and comes into the Automatic Identification (Auto-ID) technology market. Although the low cost of optical barcodes dominates them for many years, their restricted read distance, reduced information storing capacity, and significant manual involvement in their operation call out the need for an alternative. The conventional RFID overcomes all the above-mentioned shortcomings of an optical barcode. But the cost of the RFID is an important problem. This article reviews chipless RFID which benefits over existing Auto-ID technologies. An overview of the basic RFID system, categories of RFID tags, and a comparison of chipless and chipped RFID tags are outlined. Understanding the relevance of chipless RFID in the future, the classes of chipless RFID tags, the challenges that come across in designing a chipless RFID, the principle of operation of a backscattering chipless tag, and design parameters like Radar Cross Section (RCS) are discussed. This article throws light on RFID tag printing, data capturing techniques of chipless RFID, certain materials used for tag manufacturing, chipless RFID-based sensors, potential applications, followed by current challenges and future directions of chipless RFID tags.
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