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In the present situation, the world's population continues to rise rapidly, while the cultivated land suitable for cultivation stays the same. It forces farmers to demonstrate innovative techniques that improve crop yields to sustain the increasing population. Preserving the health of crops is quite critical in this respect. Therefore, early detection of disease in crops seems to be very crucial to monitor disease and increase crop yield. In this paper, a deep Convolutional Neural Network (DCNN) model is proposed using Bayesian learning process for classification of the diseases in plants. Material used for this work consist of 20,639 images taken from plantVillage having 15 distinct classes of healthy and infected leaf images of potato, tomato and pepper bell. The key objective of this research is the introduction of Bayesian process at the top of residual network for efficient feature learning. An investigation was performed for comparison of proposed DCNN with the traditional classifiers in terms of accuracy, precision, recall and F-score and result indicated that the proposed model is an efficient tool for classification of diseases. Further, the prominent physical or chemical properties of nanomaterials have enabled their use as innovative and high-performance diagnostic tools for varied plant pathogens and other important disease biomarkers. Taking these as a pre processing step while acquiring the data set and combining it with proposed work enhances the performance. The proposed approach utilizes the features developed by CNN mostly in different hierarchies to use Bayesian framework and obtains the accuracy rate of 98.9% with no sign of overfitting.

Background: Energy consumption is an important parameter in wireless sensor networks since it affects the lifetime of sensor nodes. Methods: Battery powered wireless sensor networks cannot sustain for long hence impractical for real-time applications. With energy harvesting and relevant protocols, this issue of extending the lifetime of nodes has been solved largely. The performance can be enhanced further if proper traffic analysis and modeling are done as a proactive approach. Results: A proper understanding of the traffic dynamics provides a base for further network optimization and detection of anomalies within the network. Much of the reported work in energy harvesting based WSN till now, is to design the efficient protocols only, traffic analysis and modeling is the ignored parameter. In this paper traffic models appropriate for the energy harvesting based system have been analyzed and their performance is evaluated for a MAC protocol. Conclusion: Results show that Weibull distribution is the most useful model for traffic modeling in energy harvesting based wireless sensor networks.

FRET is a nonradiative process of energy transfer that is based on the dipole-dipole interactions between molecules that are fluorescent. Transfer of energy takes place rapidly from a donor molecule to an acceptor molecule in juxtaposition such as 0 to 10 nm without photonic radiation. FRET has occupied a center stage in biotechnology and biological studies. It is used to gain information on conformation changes in single molecules. The pharmaceutical industry has also developed large fluorescence detection systems with very small sample sizes, at the level of single molecules, using fluorescence correlation spectroscopy.

The wireless sensor network is one of the promising technologies in the agriculture field. Its actual usage in real agriculture fields is limited by its dependence on the small batteries which cannot make the network survive for long. Various protocols are being designed at the network and MAC layer to increase the lifetime of the nodes, but up to a certain extent only. Hence the energy harvesting to power up the WSN nodes is a promising technology to fulfill this ever energy demand, but the protocols need to be redesigned for this scenario. Solar energy harvesting based MAC protocol which is adaptive to the changing weather conditions is designed in this paper for the smart agriculture applications. It is based on the multilayer and receiver-initiated process to improve network quality. It has shown the remarkable performance over the other energy harvesting based protocols in terms of ENO ratio, energy consumption and collision rate.

Limited availability of energy is the most crucial constraint of wireless sensor networks (WSN). Most power consuming part of WSN node is transreceiver and operation of transreciever to access medium is controlled by the medium access control (MAC) sublayer of the open systems interconnection (OSI) model. In WSN, till now, most of the present MAC protocols have addressed issues related to power saving. Because of energy constraints, performance is often not a focused design parameter in these MAC protocols. However, recent advances in energy harvesting technology have made it possible to obtain energy from the environment to solve energy limitations. So in this paper, a new multi layer based MAC protocol, MLMAC-HEAP is designed for solar energy harvesting criterion considering performance as the mainly focused parameter. Performance is illustrated in terms of throughput. This paper evaluates the performance of MLMAC-HEAP as a function of energy harvesting rate and number of nodes in network and results are compared and shown to outperform well known MAC protocols. Then, the paper analyses the protocol for various traffic models. Based on application-level requirements, optimization is also done for number of layers.

Four-wave mixing effects mitigation techniques in wavelength division multiplexing systems which utilize hybrid configurations of dispersion compensating devices like dispersion compensating fiber, fiber bragg grating and optical phase conjugator are presented in this paper. These configurations have been simulated and the output results have been compared to find out the best alternative for four-wave mixing mitigation purpose. The comparison is carried out on the basis of parametric analysis and optimized parameter values. Optimization of important parameters has been done keeping a constraint on values of quality factor and minimum bit error rate values.

Wireless sensor networks are catching the attention of the researchers in various fields like structural, healthcare monitoring, but the real world adoption is getting difficult due to its dependence on the battery power, so energy harvesting comes to its rescue. To utilize the harvested energy in the best manner, MAC protocols which control the transreceiver in a node are presented here. They are different from the battery powered WSN where the focus is on increasing the lifetime of the nodes, rather these protocols focus on improving the quality of the network. With optimal tradeoff between the infinite network lifetime and energy availability, MAC protocols need to be redesigned for energy harvesting based wireless sensor networks (EHWSN). In this paper first EH technology in wireless sensor networks is discussed. Then a survey of EH based MAC protocols is done in a classified manner. The comparison of the protocols is done based on the different metrics such as energy conservation factor, scalability, latency etc. State of the art literature survey is presented so that users have consolidated data to pick up the one based on their application requirement. Challenges specific to applications is presented along with the various gaps to give an insight into the future research directions. To the best of the author’s knowledge, review of all the EHWSN MAC protocols is not reported till date.

This paper presents a survey on the MAC and network layer of Wireless Sensor Networks. Performance requirements of the MAC layer are explored. MAC layer protocols for battery-powered networks and energy harvesting-based networks are discussed and compared. A detailed discussion on design constraints and classification of routing protocols is presented. Several routing protocols are compared in terms of such parameters as: energy consumption, scalability, network lifetime and mobility. Problems that require future research are presented. The cross-layer approach for WSNs is also surveyed.

A diopside based bioactive system with a nominal composition of xCuO-(45.55-x)CaO-29.44 SiO2-10.28P2O5-14.73 MgO (x=0,1,3 and 5mol%) has been prepared by sol gel technique in the laboratory. X-ray Diffraction, Fourier Transform Infra-Red and Raman Spectroscopy, Field Emission Scanning Electron Microscopy along with Energy Dispersive X-ray Analysis and pH studies have been undertaken on the prepared samples before and after dipping the samples in simulated body fluid. It has been observed that hydroxyapatite layer starts to form with in 24h during immersion in simulated body fluid. Degradation studies have also been employed to check the degradation behavior in Tris-HCl. Dynamic light scattering studies show that particles are mostly agglomerated and have an average size of 356nm. Zeta potential studies have been undertaken to check the surface charge and it has been estimated that samples carry negative charge when dipped in simulated body fluid. Negative surface charge may contribute to attachment and proliferation of osteoblasts. Samples have also shown the antimicrobial properties against the Vibro cholerae and Escherichia coli pathogens. To check the non-toxic nature of the samples, cell cytotoxic and cell culture studies have been undertaken using the MG-63 cell lines. Samples have shown good response with good percentage viability of the cells in the culture media and hence, provides friendly environment to the growth of cells. The particle size, bioactivity, negative values of zeta potential, antimicrobial properties and good cell viability indicate the potential of the synthesized compositions as possible candidates for bone repair applications.

Among various conventional wireless communication systems, Free Space Optics (FSO) may be distinguished as well, which provides a good level security, high data rates, an enormous bandwidth and negligible susceptibility to electromagnetic interference. The main problem arises with unfavorable weather conditions, which affect the system’s parameters and require an aversion to other paths. The weather conditions discussed are rain and haze. Elimination of their adverse effects is essential for establishing a better communication system. The routing path is a major issue, as its decreased parameters lead to the diversion of the transmitted signal or to its total loss. In this article, increased system path length and proficiency levels are demonstrated by using relays, which are assisted by Wavelength Division Multiplexing (WDM).

Free space optics (FSO) is a capable key which offers high data rate, more secure and cost effective system to other conventional communication systems. Although it is a first and last mile preference to other setups but still lags in a variety of scenarios. The main limitation of FSO is seen in worse weather conditions where it suffers highest attenuation in transmitted signal. The weather which affects the transmission most are rain and haze due to which the received signal fades away and the signal to noise ratio diminishes which violates the characteristics of an ideal FSO link system. In this paper, wavelength division multiplexing (WDM) is used to enhance the signal power with the use of optical amplifiers so that a better signal could be obtained at the receiver. A WDM-FSO system using hybrid configurations of optical amplifiers is proposed which provides a promising solution for low cost and highly efficient systems.

Free space optics has revolutionized the telecom industry through its exquisite data transfer capability and cost effectiveness. It proves out to be an excellent solution to the last mile problem and arduous digging of grounds for laying fiber optic cables. But atmospheric turbulences and obscure weather conditions limit the extensive use of this technology. This paper analyses the use of multibeam technology in enduring the effect of hazy weather on the FSO link by comparing it with the single beam technology. The results obtained from the multibeam system for clear and hazy weather conditions have been validated by using MATLAB codes.

Traditional Wireless sensor networks rely on a limited energy source, mostly batteries. But most applications need nodes to be an autonomous and continuous operation for months or years. Power consumption by sensor node is the most important part of WSN. MAC protocols help in reduction of power consumption which increases the node lifetime. But it can extend the lifetime to a certain point only, finally, we have to replace the battery. Energy harvesting along with the duty cycling come to the rescue, but now the MAC layer needs to be redesigned. In battery-based WSN the major emphasis is on lifetime only but Green Energy harvesting based protocol focus on effective energy utilization and improving the quality of the network. In this paper, new MAC protocol is designed known as Hybrid multilayer receiver initiated MAC protocol customized for the solar energy.

The present study is intended to investigate the influence of SrO doping in SiO2–CaO–MgO–P2O5 (varying SrO as 0, 1, 3 & 5 mol %) sol-gel derived bioceramics. The impact of strontium doping on structural and biological properties is assessed using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectra, degradability in simulated body fluid (SBF), Brunauer-Emmett- Teller (BET), Barret-Joyner-Halenda (BJH) and anti-oxidant activity against hydrogen peroxide (H2O2) induced oxidative stress using cell culture studies. Field emission scanning electron microscopy with energy dispersive X-ray (FESEMM-EDX) technique is used for morphological studies. The in vitro tests demonstrate that incorporation of strontium does not hinder the precipitation of the hydroxyapatite. The Zeta potential studies reveal that samples possessed negative surface charge, which might promote the binding and augmentation of osteoblasts. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) cell proliferation assay conducted on human osteosarcoma MG-63 cell line indicate significant cell survival. With regard to the antioxidant properties, samples with the highest concentration of strontium exhibits maximum protection against hydrogen-induced oxidative stress in cell culture. Thus, our studies suggest that SrO doped bioceremics demonstrate excellent physical and biological properties and strongly present their candidature as successful implant materials.

The present study focuses on the study of influence of CeO2 substitution on the structural, in vitro bioactivity, degradation, osteoblasts proliferation, oxidative stress and cell apoptosis induction in the sol-gel derived 34SiO2·8P2O5·17MgO.xCeO2.(41-x)CaO (x = 0, 0.5, 2.5 and 5 mol%) bioceramics. Zeta potential measurements were undertaken and it has shown two sign reversals with time when samples were immersed in simulated body fluid. This is mainly attributed to the adsorption of the cations from the samples and the second reversal is speculated to be due to the precipitation of the PO43− from the body like fluids. Results revealed that samples containing high amounts of cerium decrease bioactivity by forming the cerium phosphate instead of hydroxyapatite on their surfaces. In spite of the decrease in growth rate of hydroxyapatite layer formation, it is observed that maximum protection towards the oxidative stress induced by hydrogen peroxide and apoptosis is favored for higher amounts of cerium-containing samples exhibiting maximum cell viability. Our results indicate that the “sol gel” synthesis technique promotes hydroxyapatite growth rate over conventional “melt quenching” route.

The area of energy harvesting using vibration sources has attracted numerous researchers over the past few years. It has a great potential to have extended lifetime of low-power devices such as wireless sensors, portable devices, and wearable devices. The wireless devices in today’s date require batteries which have a limited lifetime and needs to be replaced with time. In case of wireless sensors that work in harsh environment, it is nearly impossible to replace batteries. The concept of energy harvesting aims to develop devices that do not require replaceable batteries. This is done by converting available energy from the environment into electrical energy to power wireless devices. This paper is focused on piezoelectric energy harvesting. First, different approaches to harvest energy have been discussed in brief. After that piezoelectric energy harvesting has been discussed in detail. Different components of piezoelectric energy harvesting circuit namely transducers, rectifiers, and storage devices have been discussed.

FSO (free-space optics) is a new technology used to solve last mile problem in point-to-point communication. As name indicated, FSO link is a seamless communication link using air as a medium for transmission of optical information. For successful transmission, medium should be free of attenuation caused by different weather conditions like rain, haze, fog. In this paper, analysis of FSO systems has been done using two 32-channel WDM systems and then compared at a constant data rate of 2.5 Gbps. The system with single laser outperforms the system employing an array of 32 CW lasers in terms of link distance under different rain conditions.

Free space optics has proved out to be an exalted technique for fast and cost-effective information exchange. Proficient in removing bandwidth limitation, it also solves the last mile problem. But as air is used as medium, it suffers from atmospheric effects which limit its achievable link distance. In this paper, a system is proposed to increase the maximum link range under different weather conditions and results have been compared with those of the previously existing system.

Free Space Optical communication (FSO) has engrossed a large section of researchers in recent times due to its wide bandwidth, effortless deployment and immune links making it appropriate for communication purposes. This wireless optical technique requires clear and non-turbulent atmospheric conditions for efficient transmission. In this paper, authors aim at reducing the effect of turbulent atmospheric conditions like scintillation effect on FSO. Multibeam technique, which uses spatially diverse transmitters for transmission, has been used for increasing the achievable link distance of the FSO system. Parameters like quality factor and bit error rate have been used to check the received signal quality.