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This paper presents analytical and numerical investigations of a 3D cylindrical metamaterial shell possessing a cylindrically anisotropic permeability that is excited by a finite-sized electric line source. A comprehensive field analysis of the system reveals that the compact metamaterial shell exhibits resonances akin to those observed in isotropic 2D cylindrical metamaterial structures, which may be used to enhance the radiated power of a nearby antenna. An analytical resonance condition that relates the dimensions of the cylindrical shell to its anisotropic effective-medium parameters is shown to be accurate in predicting the resonances of 2D and 3D metamaterial shells obtained using full-wave simulations. The effects of anisotropy and finite shell/antenna height on the system's near-fields, radiation patterns, and power-ratio enhancements are explored. It is shown through both theory and simulations that the condition for resonance is largely independent of shell/antenna height but that the quality factor reduces dramatically as these heights approach electrically small values. Also, a dispersion and loss analysis assuming Lorentz model is carried out, which indicates that practical metamaterial losses do not significantly degrade the power enhancement.

This paper presents an antenna system for scavenging ambient microwave energy. This antenna model consists of four 2×2 rectangular patch antenna arrays placed in a quad shape geometry, designed at 2.4 GHz. It provides a coverage of 360 degrees in azimuthal plane for capturing energy, thus, increasing the energy for harvesting. Maximum gain achieved by presented model is 7 dBi. Such a structure enables to either connect the rectifiers directly to each of the faces or combining RF power from all faces and connect to a single rectifier. Simulations for the antenna model were performed using ANSYS HFSS.

Users of web site usually perform their interest oriented actions by clicking or visiting web pages, which are traced in access log files. The clustering web client’s access pattern may catch common client interest in a website. The conventional web usage mining techniques for clustering web user sessions can discover usage patterns directly, but cannot identify the latent factors or hidden relationships among users’ navigational behaviour. One of the best tasks of internet usage mining, web client grouping, which sets up clusters of clients displaying comparative browsing designs gives beneficial information to customized web benefits. This paper presents a survey covering the strategies and techniques of clustering algorithms and demanding situations appear within the area.

Packet loss detection and prevention is full-size module of MANET protection systems. In trust based approach routing choices are managed with the aid of an unbiased have faith table. Traditional trust-based techniques unsuccessful to notice the essential underlying reasons of a malicious events. AODV is an approachable routing set of guidelines i.e.it finds a supply to an endpoint only on request. LDoS cyber-attacks ship assault statistics packets after period to time in a brief time period. The community multifractal ought to be episodic when LDoS cyber-attacks are hurled unpredictably. Real time programs in MANET necessitate certain QoS advantages, such as marginal end-to-end facts packet interval and unobjectionable records forfeiture. Identification of malevolent machine, information security and impenetrable direction advent in a cell system is a key tasks in any wi-fi network. However, gaining the trust of a node is very challenging, and by what capability it be able to get performed is quiet ambiguous. This paper propose a modern methodology to detect and stop the LDoS attack and preserve innocent from wicked nodes. In this paper an approach which will improve the safety in community by identifying the malicious nodes using improved quality grained packet evaluation method. The approach also multiplied the routing protection using proposed algorithm The structure also accomplish covered direction-finding to defend Adhoc community against malicious node. Experimentally conclusion factor out that device is fine fabulous for confident and more advantageous facts communication.

In places with high population and human mobility, intrusion of wildlife is lethal for humans as well as the animals. Due to the diverse nature of movement and physical sizes of wild animals, it is a challenging talk to track these animals or perform surveillance. As a solution to this issue, this paper proposes a system that can help in identification of intrusion of wild animals at agricultural farms by means of Internet of things and a Wi-Fi based wireless microcontroller unit. Prototyping is performed using Energia IDE for transmission of information to the forest officer from the transmitter node. Pillars consisting of an electronic unit with buzzer, vibration sensor, laser detector, laser diode, RF transceiver and ultra low power microcontrollers are placed at the corners of the field. On infringement, an alert message is transmitted by the Wi-Fi module. An animal database is used for testing of the proposed system. The forest officer is alerted by means of a Python server. Prevention of casualties in areas where there is a higher rate of interaction between humans and wild animals is enabled through this system.

Medical imaging is dealt with the variety of images of cross-section, tissues, blood vessels, vein, etc. of the human body that is derived by using the X-rays, MRI, CT scan, Ultrasound, Endoscopy etc. The images generated by Computed Tomography (CT Scan) of cross-sections of body are used for the diagnosis purpose by medical and healthcare experts. In order to follow an appropriate diagnosis process, the images produced by CT scan must be clearly interpretable by the medical experts. However, the images produced by CT scan are mostly suffered with the issues of lower contrast, noise, blurred, distortion, and unsharpness. So, there is a strong demand to solve all these issues for applying the diagnosis process more accurately. The main objective of this paper is to enhance the perceptual quality of images generated by CT scan. Various techniques have been used to achieve the objective, but the main technique used in proposed approach is to apply Laplacian filter for positive slope edges as well as negative slope edges along with CLAHE and Gaussian filtering. Laplacian approach has been used by various experts, but in this proposed work a Laplacian approach has been also applied on the negative slope edges. Thus both positive-slope edges and negative-slope are equally highlighted. As a result this approach assist medical expert to derive more detailed information from the image of Computed Tomography.

This paper outlines the experimental studies conducted and the results obtained in devising a health monitoring methodology by embedding polyvinylidene fluoride (PVDF) piezo-capacitive sensors within the propellant. The effect of temperature on the capacitance changes of sensor embedded inside a propellant specimen is also studied.

This paper proposes a new coplanar waveguide (CPW) fed Dielectric Resonator Antenna (DRA) with complementary characteristics. It is shown that an ultrawideband DRA can be operated as a narrow band antenna as well as a frequency notched wideband antenna by using a combinatorial loading of split ring resonators (SRR) and shunt strip between signal line and ground planes of the feeding CPW line. Using the SRRs alone yield a frequency notch in the wideband response whereas the combination of SRRs and shorting strips provides a narrowband response. Different configurations are designed and their simulated results are presented as a proof of concept.

Energy harvesting on a global, sustainable and economic scale is one of the major challenges of this century. With emerging markets, industrializations and shortage of existing resources leads to develop more effective power generation and power extraction methods. Wind energy is one of the important renewable source which is rapidly growing. The performance of wind energy conversion system is greatly enhanced with the use of full capacity power converters. The wind energy conversion system consists of a wind turbine, electric generator, power converter and suitable controllers. In this paper, Wind Energy system with full power converter using Space vector PWM inverter topology is implemented. A two level and three level Space vector PWM Inverter topology is selected here. Three level topology is discussed here in detail. The DC side boost converter is operated with PI Controller and Fractional PI controller. A detailed study is done with these controllers and inverter topologies. The simulation results helps to adequately accessing quality of power injected to the grid.

Precise information about devices in a network is crucial for the management and control of network. This information is the basic input for various functionalities of network monitoring and management. Wide variety of technologies, standards and approaches are available for the discovery of network resources. Each of these technologies has got its own advantages and disadvantages when applied to different kinds of networks. Hence the development of a generic approach for the discovery of resources for all kinds of networks is very difficult. In this paper we come up with a novel network resource discovery method for IP (Internet Protocol) networks that chooses the appropriate technology, protocol or approach based on the context of network in which the discovery is executed. To facilitate the proposed scheme, we introduce a context aware model for the network-discovery of heterogeneous networks. We have implemented this approach to discover the resources in a variety of IP networks that differ in technology and infrastructure. The results show that our scheme significantly improves the performance in terms of discovery-time, total number of devices discovered and the amount of information discovered.