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In modern phased array radars, digital beamformers are used for beam steering in transmit and receive operations. Most of the conventional radars operate in narrowband applications with phase shift beamformers. The high-resolution imaging radars operating with wide bandwidths suffer from beam squint with phase shift beamformers. In this work, a methodology is proposed to address this effect through suitable corrections in the frequency domain. The focus is given for receive beam formation with squint correction using Linearly Frequency Modulated waveforms. The paper includes the analysis of beam squint with various parameters like bandwidth and steering angle. This is supported with results and associated discussions obtained at different stages of analysis.

In this research supercapacitors were fabricated using graphene oxide (GO) as the electrode material. GO was synthesized using natural graphite precursor with varying flake sizes. GO was characterized by High Resolution Transmission Electron Microscopy (HRTEM) and Elemental Analysis. Cyclic voltammetry was carried out at different scan rates to determine the specific capacitance and energy density of the electrode material. An increase in specific capacitance was seen with increase in graphite precursor flake size. A specific capacitance and energy density of 204.22 F.g−1 and 102.11 kJ.kg−1 respectively at scan rate 10 mV.s−1 was obtained for the GO sample synthesised from graphite precursor with an average particle size of 0.45 mm. This sample also had the highest specific capacitance for all scan rates.

In this research high temperature superconductor material (YBCO) was doped with graphene oxide (GO) and reduced graphene oxide (rGO) in 0.5 % wt. and 0.7 % wt. concentrations. Resistance versus Temperature (R vs. T) measurements were carried out in field cooling (FC) and zero field cooling (ZFC) conditions. In order to determine the critical transition temperature (Tc) and observe the effect of doping on the weak-links. The increase in Tc was greater in GO doped samples compared to rGO doped samples, this is due to the increase in oxygen content in the doped samples which was confirmed by iodometric titration. The weak-link effect was improved in both GO and rGO doped samples. The reduction of the weak-link effect implies YBCO material with a higher critical current density (Jc).

Bulk high temperature superconductors (HTS) in their non-textured form consists of a network of weak-links at its grain boundaries. The weak-links are a result of an incorrect stoichiometric ratio or misaligned grain planes, and greatly reduce the critical current density. High temperature bulk superconductor, in our case Y 1 Ba 2 Cu 3 O 7-δ (YBCO), was doped with graphene oxide in the following weight percentages: 0, 0.5 and 0.7 wt. %. Resistance vs Temperature measurements were taken in zero field cooling (ZFC) and field cooling (FC) conditions in order to determine critical transition temperature (T c ) and to study the effect on the weak-links. It is observed that T c in doped samples increased and there is an improvement in the weak-link effect in doped samples.

Now a days the usage of Self-Organizing Networks (SONs) is increasing, because of its wide application. Unlike common networks the SONs have the capability of reconfiguration, whenever any defect occurs in the network. Some of the SONs are Mobile Ad hoc Network (MANET), Wireless Sensor Network (WSN), Vehicular Ad hoc Network (VANET) and Wireless Mesh Network (WMN). In common nodes in these kinds of networks are mobile in nature, but these nodes can create new topology at the instant it shifts its position. However, in these networks the loss of data may occur while routing due to its security lack. Hence many researchers have presented their research for providing secure routing in various SONs. Hoverer the security is still an issue in routing of SONs especially MANET. In this paper, we have developed a novel protocol for the secure routing in SONs, which is termed as Trust-Distrust Protocol (TDP). As per the proposed protocol, the routing is done in four stages. In the initial stage topology management using an improved pillar k-means algorithm. The second stage is Link Quality Appraisal (LQA) based on the fitness of nodes. The third stage is grading, in which a grade point is allotted to every node based on LQA. In the last stage the secure path for the routing is determined based on the grade point. The proposed protocol is tested in one of the major kinds of SONs, like MANET using the MATLAB research tool. Ultimately the proposed protocol outperform the performance of the existing routing strategies.

The image encryption or the secure image pro-cessing is an art of handling the image to provide protection from those image information theft or damage. It is necessary to maintain security for images such as medical, military, etc. So far many research work have been developed in the field of image information security and prevention. However the achieved level of security is not satisfactory, thus still this field is in research to find a better solution for the image data security and prevention. In this sense, this research is targeted to develop a better strategy for the image data prevention and security enhancement. There are many cryptography technique is available in the technical world, however this work adapted quaternion based approach for the image data security. Qua-ternion is a kind of number notation, it is the combination of both scalar and vector. Quaternion rotation is the concept applied in the image encryption for the security purpose. In the existing works authors have applied the Quaternion rotation based encryption of medical image and color images. In order to further enhance the performance of encryption, in this work the Quaternion Fourier Transform is applied. The Fourier transform based Quaternion rotation improves the performance in both security and computation. The proposed system is implemented using the working platform of MATLAB, and the performance is compared with the conventional quaternion technique. The proposed system provided better performance based on the comparative analysis with respect to correlation coefficient, avalanche effect, computational speed, normalized correlation and histogram.

Breast tumor is a champion among the most broadly perceived sort of development among women that creates from breast tissue. Still the correct reason for the breast disease stays obscure. Early discovery and determination is the best methodology to control the tumor movement. Mammography is the right now suggested imaging strategy for early assurance and determination of breast danger. A mammogram can distinguish unusual areas in the breast that resemble a malignancy. Mammogram pictures are observed to be hard to decipher so a CAD is turning into an undeniably essential device to help radiologist in the mammographic lesion interpretation. Preprocessing was considered as an essential stride in mammogram picture investigation. Exactness of preprocessing will decide the achievement of the rest of the procedure, for example, segmentation, classification and so forth. In this paper, mean, median, adaptive median, gaussian and wiener denoising filters are utilized to evacuate salt and pepper, speckle and gaussian noises from a mammogram picture and these filters were looked at in light of the parameters, for example, PSNR, MSE and SNR to figure out which filter is better to remove these noises in mammogram pictures. The segmentation is a process in which changing the representation of an image such that it is easier to analyse. This paper compares various mass segmentation techniques used in mammogram images.

Retinal fundus image morphology indicates diseases like diabetic retinopathy and glaucoma like diseases. Blood vessel features of the retinal image allow ophthalmologist to perform retinal disease evaluation. Presence of lesions in the fundus image is initial sign of diabetic retinopathy. Preprocessing technique is mainly used to remove unwanted noises and it enhances some image features. Different types of pre-processing techniques are used for image processing. This paper represents the comparison of different methods used for pre-processing in retinal fundus image.

Wireless networks have dominated wired. Wireless networks can be infrastructure based or infrastructureless. The MANET nodes act as both router and the end-user. MANET nodes should not maintain their position to establish a wireless interconnection. So, there is a chance for the network to be disconnected. This phenomenon is called as network partitioning. The technique of data replication has been widely discussed in order to improve data accessibility which decreases due to network partitioning. But, some nodes will show their selfish behavior so that effective replica allocation will become a failure. To inform the network nodes about this selfish behavior, a selfishness alarm will be raised. But, the alarm may also be initiated because of the same problem of network disconnections, and seems to be treated as the overall selfishness alarm. Such an alarm can be called as a false alarm. Here, we propose an innovative technique to detect this false selfishness alarm; and also to differentiate it from the actual selfishness alarm by setting a threshold value. The analysis of network parameters like link duration time and available energy are considered further to detect the broken link. Therefore, the selfish nodes can be eliminated properly; and then data replicas can be allocated to every non-selfish node effectively.

The basic mode of transportation for limited distances is mainly through road ways. As the problem of urban traffic congestion spreads, there is a pressing need for the introduction of advanced technology and equipment to improve the state-of-the-art traffic control. Traffic problems nowadays are increasing because of the growing number of vehicles and the limited resources provided by current infrastructures. Due to this, there is a need to wait for more time in front of the signals. This leads to waste of time. In concern with this problem, we have designed a paper that will help the people in taking the alternate routes in times of long traffic In the proposed method, vehicles count in the traffic is detected using image processing techniques. A camera will be installed along with the traffic light on the signalling post It will capture the image sequences. The image of an empty road is taken as the reference image and background subtraction is performed with the captured image to detect the traffic density. The vehicles on the captured road images will be counted. The vehicles count is updated in the SQL server through RF signals. Unique code win be assigned to the local server. By sending message to that code providing the name of the signal area, its traffic detail will be sent to the corresponding user. According to the received message from the signal area, people choose heir alternate way for their timely reach to their job or occasion. This will be used for all the local area working people. This reduces the waiting time in the traffic signals when the vehicles count is higher. The paper results in reducing the waiting time in the traffic signals as the traffic is set according to the traffic density. Hence the traffic movement will be smooth.

CdO thin films have great technological interest due to their high-quality electrical and optical properties. Mixed oxides of CdO have been used in photovoltaic devices, gas sensors, phototransistors etc. In this work, the Acrylamide route was used to deposit CdO: In films. XRD patterns of the undoped and indium-doped CdO films exhibit cubic structure of the cadmium oxide with five characteristic peaks assignable to the (111), (200), (220), (311) and (222) planes. The intensity of the peaks decreases and the full-width at half-maximum (FWHM) increases as the indium content increases. The resistivity of the films decreases by two orders with Indium doping. It is observed that all the deposited films exhibited high transmission of about 70–90% in the visible range of 500–600 nm. The value for CdO film without doping is 2.41 eV, while the doping of 6 at wt% indium results in an increase of band gap to 2.97 eV. Surface morphology studies with Atomic force microscope indicated the formation of nanocrystallites with surface roughness around 0.3 nm.

This paper presents methodology and case studies for a system-wide evaluation of an integrated traffic control and route diversion strategy. Traffic density management using DESBOR technology and GPS is an attempt for the creation of the smooth driving environment through a variety of recent technologies such as DESBOR, GPS and WI-FI. With these technologies we can make people not to wait for a long time in traffic signals with fewer vehicles on the other side of the signal system. This technology makes the signal system to work on the vehicle density basis whereas the existing system is on the time basis. This system can be extended to personnel vehicles also. This technology can serve its purpose greatly when it is implemented on the emergency vehicles such as Ambulances and Rescue vehicles. This technology can play a vital role in fuel savings and pollution control.

While executing a process, many decisions are taken at its various decision points for selecting paths. There is a need for understanding and analyzing on various paths that emanate from various decision points to ensure that right decision is taken at these moments. For this purpose, this paper presents the notion of hyperpaths in the context of workflows, its properties, and an algorithm to generate various hyperpaths from a node of a workflow graph. The algorithm is presented with detailed workouts using examples. The paper also details various similarities between hyperpaths and related concepts like instance subgraphs, instance flows, etc., and briefs on various algorithms available in literature for such concepts. Finally, the paper presents various applications of hyperpaths such as process mining, business process re-engineering, etc. Hyperpaths can be used in service-oriented computing model for resource management, business activity monitoring (BAM), dynamic orchestration, and mission-critical service oriented systems.

The design, simulation, and testing results of a CMOS ASIC are presented for mapping the outputs of multiple instantaneous frequency measurement correlation to a spectral estimation of the center frequency of submicrosecond pulses in real time. Preliminary testing indicated fully functional designs. >

A VHSIC Hardware Description Language (VHDL) Automatic Test Pattern Generator (ATPG) system to perform behavioral fault modeling and simulation is discussed. The input to the VHDL ATPG system is VHDL at the behavioral level. The behavioral fault model analyzer generates the behavioral faulty files for each fault simulated. The behavioral faulty files are input to both the behavioral fault simulator and the test bench generator. The test bench generator, at the request of user, produces a fault simulation test bench which is applied to the behavioral fault simulator for simulating the faulty files and reference model, respectively. The outputs of these two simulators are compared in the fault simulation comparator which generates the simulation report. The authors analyze the gap of the fault model and fault simulation between the behavioral level and gate level circuit description and show the one to one correspondence with typical examples. The authors demonstrate the effectiveness of behavioral fault modeling and simulation by illustrations of applying the method to practical examples. >

A custom CMOS ASIC is designed for a 32 bit binary to residue converter (BRC) to permit residue number system (RNS) operations using 8 moduli with 3 to 5 bit words. A custom ASIC design is also given for the corresponding residue to binary converter (RBC) to convert the 8 RNS moduli words to a unique 32 bit binary number. The result is a complete simulated pipelined design which supports a clock frequency of 50 MHz. These designs are directly applicable to RNS operations for digital signal processing and to direct frequency synthesis. >