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The purpose of this paper is to present the design of a piezoelectric vibration energy generator with a power conditioning circuit to power a wireless sensor node. Frequency and voltage characterization of the piezoelectric energy harvester is performed. A single-stage AC–DC power converter that integrates the rectification and boosting circuit is designed, simulated and implemented in hardware.

The designed power conditioning circuit incorporates bridgeless boost rectification, a lithium ion battery as an energy storage unit and voltage regulation to extract maximum power from PZT-5H and to attain higher efficiency. The sensor node is modelled in active and sleep states on the basis of the power consumption. Dynamic modelling of the lithium ion battery with its state of charging and discharging is analysed.

The test result shows that the energy harvester produces a maximum power of 65.9 mW at the resonant frequency of 21.4 Hz. The designed circuit will operate even at a minimum input voltage of 0.5 V. The output from the harvester is rectified, boosted to a 7-V DC output and regulated to 3.3 V to the power C_Mote wireless sensor node. The conversion efficiency of the circuit is improved to 70.03 per cent with a reduced loss of 19.76 mW.

The performance of the energy harvester and the single-stage power conditioning circuit is analysed. Further, the design and implementation of the proposed circuit lead to an improved conversion efficiency of 70.03 per cent with a reduced loss of 19.76 mW. The vibration energy harvester is integrated with a power conditioning circuit to power a wireless sensor node C_Mote. The piezoelectric vibration energy harvester is implemented in real time to power C_Mote.

Energy is the major concern in wireless sensor networks (WSNs) for most of the applications. There exist many factors for higher energy consumption in WSNs. The purpose of this work is to increase the coverage area maintaining the minimum possible nodes or sensors.

This paper has proposed multilayer (ML) nodes deployment with distributed MAC (DS-MAC) in which nodes listen time is controlled based on communication of neighbors. Game theory optimization helps in addressing path loss constraints while selecting path toward base stations (BS).

The simulation is carried out using NS-2.35, and it shows better performance in ML DS-MAC compared to random topology in DS-MAC with same number of BS. The proposed method improves performance of network in terms of energy consumption, network lifetime and better throughput.

Energy consumption is the major problem in WSNs and for which there exist many reasons, and many approaches are being proposed by researchers based on application in which WSN is used. Node mobility, topology, multitier and ML deployment and path loss constraints are some of the concerns in WSNs.

Game theory is used in different situations like countries whose army race, business firms that are competing, animals generally fighting for prey, political parties competing for vote, penalty kicks for the players in football and so on.

WSNs find applications in surveillance, monitoring, inspections for wild life, sea life, underground pipes and so on.

Game theory optimization helps in addressing path loss constraints while selecting path toward BS.

This paper aims to present the design of a cantilever beam with various kinds of geometries for application in energy harvesting devices with a view to enhance the harvested power. The cantilever beams in rectangular, triangular and trapezoidal geometries are simulated, designed and evaluated experimentally. A power conditioning circuit is designed and fabricated for rectification and regulation.

The analytical model based on Euler–Bernoulli beam theory is analyzed for various cantilever geometries. The aluminum beam with Lead Zirconate Titanate (PZT) 5H strip is used for performing frequency, displacement, strain distribution, stress and potential analysis. A comparative analysis is done based on the estimated performance of the cantilevers with different topologies of 4,500 mm³ volume.

The analysis shows the trapezoidal cantilever yielding a maximum voltage of 66.13 V at 30 Hz. It exhibits maximum power density of 171.29 W/mm³ at optimal resistive load of 330 kΩ. The generated power of 770.8 µW is used to power up a C-mote wireless sensor network.

This study provides a complete structural analysis and implementation of the cantilever for energy harvesting application, integration of power conditioning circuit with the energy harvester and evaluation of the designed cantilevers under various performance metrics.

The current and on-going coronavirus (COVID-19) has disrupted many human lives all over the world and seems very difficult to confront this global crisis as the infection is transmitted by physical contact. As no vaccine or medical treatment made available till date, the only solution is to detect the COVID-19 cases, block the transmission, isolate the infected and protect the susceptible population. In this scenario, the pervasive computing becomes essential, as it is environment-centric and data acquisition via smart devices provides better way for analysing diseases with various parameters.

For data collection, Infrared Thermometer, Hikvision’s Thermographic Camera and Acoustic device are deployed. Data-imputation is carried out by principal component analysis. A mathematical model susceptible, infected and recovered (SIR) is implemented for classifying COVID-19 cases. The recurrent neural network (RNN) with long-term short memory is enacted to predict the COVID-19 disease.

Machine learning models are very efficient in predicting diseases. In the proposed research work, besides contribution of smart devices, Artificial Intelligence detector is deployed to reduce false alarms. A mathematical model SIR is integrated with machine learning techniques for better classification. Implementation of RNN with Long Short Term Memory (LSTM) model furnishes better prediction holding the previous history.

The proposed research collected COVID −19 data using three types of sensors for temperature sensing and detecting the respiratory rate. After pre-processing, 300 instances are taken for experimental results considering the demographic features: Sex, Patient Age, Temperature, Finding and Clinical Trials. Classification is performed using SIR mode and finally predicted 188 confirmed cases using RNN with LSTM model.

The purpose of this work is to reduce the power consumption of KSA and to improve the PDP for data path applications. In digital Very Large – Scale Integration systems, the addition of two numbers is one of the essential functions. This arithmetic function is used in the modern digital signal processors and microprocessors. The operating speed of these processors depends on the computation of the arithmetic function. The speed computation block for most of the datapath elements was adders. In this paper, the Kogge–Stone adder (KSA) is designed using XOR, AND and proposed OR gates. The proposed OR gate has less power consumption due to the less number of transistors. In arithmetic logic circuit power, delay and power delay products (PDP) are considered as the important parameters. The delays reported for the proposed OR gate are less when compared with the conventional Complementary Metal Oxide Semiconductor (CMOS) OR gate and pre-existing logic styles. The proposed circuits are optimized in terms of power, delay and PDP. To analyze the performance of KSA, extensive Cadence Virtuoso simulations are used. From the simulation results based on 45 nm CMOS process, it was observed that the proposed design has obtained 688.3 nW of power consumption, 0.81 ns of delay and 0.55 fJ of PDP at 1.1 V.

In this paper, a new circuit for OR gate is proposed. The KSA is designed using XOR, AND and proposed OR gates.

The proposed OR gate has less power consumption due to the less number of transistors. The delays reported for the proposed OR gate are less when compared with the conventional CMOS OR gate and pre-existing logic styles. The proposed circuits are optimized in terms of power, delay and PDP.

In arithmetic logic circuit power, delay and PDP are considered as the important parameters. In this paper, a new circuit for OR gate is proposed. The power consumption of the designed KSA using the proposed OR gate is very less when compared with the conventional KSA. Simulation results show that the performance of the proposed KSA are improved and suitable for high speed applications.

In the past few decades, the wireless sensor network (WSN) has become the more vital one with the involvement of the conventional WSNs and wireless multimedia sensor networks (WMSNs). The network that is composed of low-power, small-size, low-cost sensors is said to be WSN. Here, the communication information is handled using the multiple hop and offers only a simple sensing data, such as humidity, temperature and so on, whereas WMSNs are referred as the distributed sensing networks that are composed of video cameras, which contain the sector sense area. These WMSNs can send, receive and process the video information data, which is more intensive and complicated by wrapping with wireless transceiver. The WSNs and the WMSNs are varied in terms of their characteristic of turnablity and directivity.

The main intention of this paper is to maximize the lifetime of network with reduced energy consumption by using an advanced optimization algorithm. The optimal transmission radius is achieved by optimizing the system parameter to transmit the sensor information to the consequent sensor nodes, which are contained within the range. For this optimal selection, this paper proposes a new modified lion algorithm (LA), the so-called cub pool-linked lion algorithm (CLA). The next contribution is on the optimal selection of cluster head (CH) by the proposed algorithm. Finally, the performance of proposed model is validated and compared over the other traditional methods in terms of network energy, convergence rate and alive nodes.

The proposed model's cost function relies in the range of 74–78. From the result, it is clear that at sixth iteration, the proposed model’s performance attains less cost function, that is, 11.14, 9.78, 7.26, 4.49 and 4.13% better than Genetic Algorithm (GA), Dragonfly Algorithm (DA), Particle Swarm Optimization (PSO), Glowworm Swarm Optimization (GSO) and Firefly (FF), correspondingly. The performance of the proposed model at eighth iteration is 14.15, 7.96, 4.36, 7.73, 7.38 and 3.39% superior to GA, DA, PSO, GSO, FF and LA, correspondingly with less convergence rate.

This paper presents a new optimization technique for increasing the network lifetime with reduced energy consumption. This is the first work that utilizes CLA for optimization problems.

The purpose of this paper is to fabricate an ethanol sensor which has bio-friendly and eco-friendly properties compared to the commercially available ethanol sensors.

This paper describes the construction of a highly sensitive ethanol sensor with low ppm level detection at room temperature by integrating three techniques. The first deals with the formation of organic/inorganic p-n heterojunction. Second, tuning of structural parameters such as length, diameter and density of Zinc Oxide (ZnO) nanostructure was achieved through introduction of the Fe dopant into a pure ZnO seed layer. Furthermore, ultra-violet (UV) light photoactivation approach was used for enhancing the sensing performance of the fabricated sensors. Four different sensors were fabricated by combing the above approaches. The structural, morphological, optical and material compositions were characterized using different characterization techniques. Sensing behavior of the fabricated sensors toward ethanol was experimented at room temperature with and without UV illumination combined with stability studies. It was observed that all the fabricated sensors showed enhanced sensing performance for 10 ppm of ethanol. In specific, FNZ (Fe-doped ZnO seeded Ni-doped Zn nanorods) sensor exhibited a higher response at 2.2 and 13.5 s for 5 ppm and 100 ppm of ethanol with UV light illumination at room temperature, respectively. The photoactivated FNZ sensor showed quick response and speedy recovery at 18 and 30 s, respectively, for 100 ppm ethanol.

In this study, the authors have experimentally analyzed the effect of Fe (in ZnO seed layer and ZnO NRs) and Ni (in ZnO NRs) dopants in the room temperature sensing performance (with and without UV light) of the fabricated ethanol sensors. Important sensing parameters like sensitivity, recovery and response time of all the fabricated sensors are reported.

The Fe doped ZnO seeded Ni doped Zn nanorods (FNZ sample) showed a higher response at 2.2 s and 13.5 s for very low 5 ppm and 10 ppm of ethanol at room temperature under UV light illumination when compared to the other fabricated sensors in this paper. Similarly, this sensor also had quick response (18 s) and speedy recovery (30 s) for 100 ppm ethanol.

Historically, as a result of complex intersections of marginalisation, women and girls in India are known to have had less access to economic and social capital than men and boys. Progress on poverty alleviation and the advancement of women’s and girls’ development continues to be slow and has even been described as ‘regressive’ (UN Women, 2015). This chapter provides a microanalysis of experiences and perceptions of gender and poverty in Mumbai, India. It puts forward new insights into everyday forms of agency, resistance and subversion while confronting western centric ideas around development and colonialist notions of victimhood.

Based upon research conducted in 2012–2013, the qualitative study adopting a multi-methods approach draws on participatory action research, participant observation and ethnography. This chapter draws on a small number of interviews from the original sample of 40 participants.

This chapter is based on findings from a small research sample.

The study finds evidence that confirms experiences of gendered poverty permeate across class divides, suggesting that access to economic capital does not necessarily result in equitable gender relations. The findings also uncover the diverse ways in which women and adolescent girls strategise and negotiate to acquire agency, through acts of resistance and/or subversion.

There are two key aspects of this research that can be considered original: the use of a multi-methods approach and by bringing together of a combination of different voices. The theoretical and sociological contribution of this research lies in showcasing the value of expanding the definition of poverty and gender beyond a purely economic analysis.

This study aims to investigate some physicochemical characteristics of Hildegardia barteri seed oils obtained by cold-pressing and solvent extraction procedures.

Crude oil samples were obtained from the kernels by cold pressing and solvent extraction. The physicochemical properties of the oil samples were investigated according to the standard procedures in published works of literature.

The oil yield was 55.7 and 97 per cent for cold-pressed kariya seed oil (CPKSO) and solvent-extracted kariya seed oil (SEKSO), respectively. Specific gravities, refractive indices, viscosities, iodine value, saponification value, peroxide value and acid value were 0.8742 and 0.9036; 1.4629 and 1.4584; 75.93 and 74.90 mPa.s; 55.78 and 53.56 g of I2/100g of oil; 249.76 and 253.90 mg KOH/g; 4.86 and 5.02 meq KOH/g; 2.12 and 2.09 mg KOH/g of oil for CPKSO and SEKSO, respectively. The physicochemical characteristics of kariya seed oil were not significantly affected by extraction method. The fatty acid profiles of CPKSO and SEKSO showed that the two oil samples contain 24.2 and 23.7, 31.3 and 29.3, 23.2 and 23.7 and 19.6 and 21.3 per cent of myristic, palmitic, stearic and linolenic acids, respectively. Lauric and oleic acids were present in very little proportions of 0.3 and 0.41; and 0.01 and 0.03 per cent, respectively, whereas linoleic acid was 1.4 per cent for the two oil samples. Significant differences in fatty acid profiles were observed for lauric, palmitic and linolenic acids (p = 0.05). Saturated and unsaturated fatty acids were about 79.0 and 77.11 per cent and 21.01 and 22.73 per cent for CPKSO and SEKSO, respectively.

This work promotes H. barteri tree beyond its use as a mere ornamental plant. The non-conventional seed oil it produces may find relevance in the food or biofuels industry subject to further investigation.

This study is the first to document the extraction and physicochemical properties of kariya seed oils.

Various approaches have been made to alter the vibration sensing properties of zinc oxide (ZnO) films to achieve high sensitivity. This paper aims to report the experimental study of the fabrication of precursor molar ratio concentration varied ZnO nanostructures grown on rigid substrates using the refresh hydrothermal method. The effect of these fabricated ZnO nanostructures-based vibration sensors was experimentally investigated using a vibration sensing setup.

ZnO nanostructures have been grown using low temperature assisted refresh hydrothermal method with different precursor molar concentrations 0.025 M (R1), 0.075 M (R2) and 0.125 M (R3). Poly 3,4-ethylenedioxythiophene polystyrene sulfonate, a p-type material is spun coated on the grown ZnO nanostructures. Structural analysis reveals the increased intensity of the (002) plane and better c-axis orientation of the R2 and R3 sample comparatively. Morphological examination shows the changes in the grown nanostructures upon increasing the precursor molar concentration. The optical band gap value decreases from 3.11 eV to 3.08 eV as the precursor molar concentration is increased. Photoconductivity study confirms the formation of a p-n junction with less turn-on voltage for all the fabricated devices. A less internal resistance of 0.37 kΩ was obtained from Nyquist analysis for R2 compared with the other two fabricated samples. Vibration testing experimentation showed an improved output voltage of the R2 sample (2.61 V at 9 Hz resonant frequency and 2.90 V for 1 g acceleration) comparatively. This also gave an increased sensitivity of 4.68 V/g confirming its better performance when compared to the other fabricated two samples.

Photoconductivity study confirms the formation of a p-n junction with less turn-on voltage for all the fabricated devices. A less internal resistance of 0.37 kΩ was calculated from the Nyquist plot. Vibration testing experimentation proves an increased sensitivity of 4.68 V/g confirming its better performance when compared to the other fabricated two samples.

Vibration testing experimentation proves an increased sensitivity of 4.68 V/g for R2 confirming its better performance when compared to the other fabricated two samples.