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The validity of some of the assumptions made during systematic development of constitutive relation – homogeneity, isotropy, and non-dissipative response – is examined experimentally by testing plain concrete cylinders in the circumferential displacement controlled uniaxial compression tests. The tested cylinders indicate that the surface strains are not uniform and that the principal direction of the strain varies with the magnitude of the applied load. Hence, these cylinders are either deforming from a stressed state or anisotropic or both. The percentage dissipation computed as the area between the loading and unloading curves normalized using the area under the unloading curve is less than 10 percent up to 90 percent of the peak load. Therefore the mechanical response of concrete can be considered as non-dissipative. Assuming that the magnitude of the residual stresses present in the concrete panels would be small compared to the stresses arising due to the applied load, these residual stresses are ignored. Consequently, using the implicit constitutive theory framework for isotropic and compressible materials undergoing a non-dissipative process from a stress-free reference configuration, a three-dimensional constitutive relation for plain concrete is proposed. The material parameters in the proposed model are estimated from the uniaxial compression test and equal biaxial compression test. These parameters are expressed using initial Young’s modulus, initial Poisson’s ratio, maximum uniaxial compressive stress, the axial and transverse strain corresponding to the maximum uniaxial compressive stress, maximum equal biaxial compressive stress and the equal biaxial strain corresponding to maximum equal biaxial compressive stress. The ability of the proposed model to capture the response of various grade and type of concrete in ten biaxial experiments reported in the literature is examined. It is found that despite the limiting assumptions, the compression-compression, compression-tension and tension-tension stress strain response of the concrete in these ten experiments are adequately captured by the proposed model with mean R 2 value of 0.94.

Mobile adhoc network (MANET) is an infrastructure less wireless network and self-organized. During communication mobile adhoc network do not use any proper infrastructure so that MANET initiates request for data transfer, so MANET is vulnerable to various type of attacks such as black hole attack, warm hole attack, gray hole attack. The proposed system is to detect the malicious behavior of node by intrusion detection system with fuzzy logic technique and also to identify the type of attacks. The system is robust enough to detect attacks such as black hole attack and gray hole attack and also able to prevent those kind of attacks by using efficient node blocking mechanism such that the proposed system provides a secure communication between nodes

A methodology for obtaining implicit constitutive representations involving the Cauchy stress and the Hencky strain for isotropic materials undergoing a non-dissipative process is developed. Using this methodology, a general constitutive representation for a subclass of implicit models relating the Cauchy stress and the Hencky strain is obtained for an isotropic material with no internal constraints. It is shown that even for this subclass, unlike classical Green elasticity, one has to specify three potentials to relate the Cauchy stress and the Hencky strain. Then, a procedure to obtain implicit constitutive representations for isotropic materials with internal constraints is presented. As an illustration, it is shown that for incompressible materials the Cauchy stress and the Hencky strain could be related through a single potential. Finally, constitutive approximations are obtained when the displacement gradient is small.

The paper presents the synthesis, characterization of Lanthanum substituted Barium ferrite material and its real time application in the development of miniaturised navigational antenna at 2.492 GHz. The Lanthanum substitution is observed to increase the ferro magnetic resonance frequency of BaFe12O19 parent material because of its octahedral site preference. Among the synthesized material, the BaLa0.2Fe11.8O19 material has resulted in higher effective magnetic permeability of around 2.5 and dielectric permittivity of around 5.5. The Quadrifilar helix antenna which is miniaturised by loading the BaLa0.2Fe11.8O19 material has the axial height reduction of 59% compared to the conventional quadrifilar helix antenna, while retaining the radiation characteristics like gain and band width.

Background: Internet of Things (IoT) is the next emerging technique in which each and every thing in the world is getting connected to the internet by means of various communication techniques. By using the technique of multicasting, these things communicate with each other to transfer the data. So there is a need of an authentication scheme in order to prevent the data form getting corrupted while transmitting. As we know trillions of devices are connected in IoT, a secure communication should be implemented for the same. So a light weight authentication should be provided for IoT. Methods: The IoT consist of many objects, the objects may me mobile phones, refrigerator, air cooler etc. along with sensors, actuators, base station. The objects are mainly connected with sensors in order to retrieve data from each of them. Since sensor network is adhoc networks and the computational power consumed of sensor networks are also very low. Hence in the Wireless Sensor Network (WSN) many sensors are connected with one or more base station. The base station in wireless sensor network manages all the sensor nodes with the help of processor and memory. Since we are transforming from wireless sensor networks to IoT, the objects are connected to internet by providing address to individual object. So, the base station not having the capable to provide a secure communication between the objects along with sensors and internet.In this paper, we propose a new authentication scheme by means of two different approaches. Since IoT contains many numbers of objects, we connect certain objects which are in same area and provide a database for that object. The data related to particular node is stored and updated frequently in the database and maintained by Data Base Management System (DBMS) and it is connected to internet. Results: Whenever a user wants to access the data, the authentication is provided by means of login id with hashing password or with the help of MAC passwords. These two authentication scheme provide better when compared to existing method which are shown in results. The metrics that measures the performance of the proposed approach are the resistance against node compromise,computation overhead,communication overhead, robustness to packet loss and message entropy. Applications: This main application of mutual authentication scheme for IoT is to provide a authentication between the end user and the sensor network data. This method is also suitable for smart house application where the user can securely access the data from anywhere in the world.

Due to raising concerns about the privacy preserving of personal information, organizations which are using the customers' records in data mining activities are rammed to take actions for protecting the individual's privacy. Preserving of sensitive and personal information is vital for the success of data mining techniques. Privacy Preserving Data Mining (PPDM) handles such consequences by reconciliation of both preserving privacy and data utilization. Conventionally, Geometrical Data Transformation Methods (GDTMs) have been extensively used for privacy conserving cluster. The major drawback in these GDTMs are geometric conversion function are not reversible, that results in a low level assurance of security. In this paper, the technique that preserves the privacy of delicate information in a multiparty cluster situation called the guideline segment investigation based technique is proposed. The function of this proficiency is assessed advance by employing a classic K-means cluster algorithms and machine learning-based cluster methodology on artificial and realistic world information sets. The effectiveness of grouping is computed prior and then afterward the change of security preserving. Our suggested transformation established on PCA when competed to the traditional GDTMs resulted in superior protection of privacy and improve performance.

In order to deal with the wireless camera networks (WCNs), whose detecting power of conventional camera networks with elasticity, reconfigurability and with a simple deployment of wireless sensor networks (WSN) for efficiently addressing the significant responsibilities in the method of cluster based human (object) tracking, such as integrating the measurement, including or ruling out in the cluster and cluster head rotation. The WCN effectively uses division friendly representation and methods in which every node contributes to the estimation in each methodology without the requirement of any previous information of the remaining the nodes. These methods are integrated in two different schemas so that they can be deployed with the same mean time without considering the cluster size. Thus, the observation and practical evaluation shows that the proposed schemes and methodology drastically reduces the energy consumption and computational trouble in accordance to the existing methodology.

In this paper, Genetic Algorithm (GA) is used for identifying two bioprocesses. Bioprocesses are highly nonlinear systems and hence conventional techniques such as Recursive Least Squares (RLS) cannot be used to identify these systems. Systems chosen for identification are fed batch fermentor and bioreactor. Simulation results are presented for the above cases and are found to be satisfactory.