Encrypted Biography of Biomedical Image - a Pentalayer Cryptosystem on FPGA

Secure transmission of medical information occupies a crucial role in the world of telemedicine applications. Reconfigurable hardware implementation offers several advantages over software implementation especially for real time security applications. This work aims to propose the novel implementation of a penta-layer medical image encryption using a reconfigurable Cyclone II Field Programmable Gate Array (FPGA) EP2C35F672C6. The first layer of encryption performs the row-wise and column-wise pixel permutations based on Linear Feedback Shift Register (LFSR). The second and third layers of encryption are based on maximal length sequence Pseudo Random Number Generator (PRNG) 16-bit Cellular automata (CA) circuit and Galois Field (GF) product. In the fourth layer, a synthetic image is subsequently created by chaotic clock with Phase Lock Loop (PLLs) and gates to diffuse the image pixels. This creation of synthetic image for diffusion makes the developed cryptosystem totally hardware dependent. Last layer performs the diffusion using one dimensional logistic map. The synthesized result reveals that the reconfigurable implementation of proposed encryption process consumes comparatively lesser logic elements (2480) and low power consumption (278.65 mW) with an encryption time of 215.92 ms for encrypting a 256?×?256 DICOM medical image. Finally, various analyses such as Number of Pixel Change Rate (NPCR), Unified Average Change in Intensity (UACI), Entropy, Correlation, Uniform distribution and NIST statistical test suite have been performed to prove the robustness of the algorithm against various attacks.

     

Applicability of Cavity Modeling Technique to Analyze Complex Waveguide Structures Involving Cavity Cross Couplings

Wireless Personal Communications - In this paper, we propose modulation and coding scheme level drop scheme for LTE evolved multimedia broadcast/multicast service (eMBMS) by transmitting additional...     

Measurement of ultrasonic velocity with improved accuracy in pulse echo setup

In the present work a personal computer based circuit adopted in pulseecho setup has been developed for the measurement of time-of-flight between the two successive echoes using a differential time measurement with a 16 bit counter and an external clock frequency of 32 MHz. A control program is developed in C to display the time of flight and wave propagation velocity on a user screen. The technique, so developed, minimizes the errors in time delay measurements due to the variation in threshold trigger points of echoes and improves the ultrasonic velocity measurement.     

Minimizing probable collision pairs searched in interactive animation authoring

Animation authoring involves an author’s interaction with a scene, resulting in varying scene complexity for a given animation sequence. In such a varying environment, detection and prediction of collision in minimal time and with high accuracy is a challenge. This paper proposes using the bounding volume-based space subdivision mechanism to reduce search space for an object pair collision search. This data structure is enhanced using a direction-based spatial hash table, which predicts collision between static and dynamic objects. These techniques are shown to work in conjunction with existing search space reduction methods. The event of collision is accurately detected using known methods, such as kinetic data structures. Simulation results show that for a scene with 10000 objects with varying dynamic objects (10–90%), the method finds probable collision-pairs with 95–99% accuracy.     

Deacidification of soybean oil by membrane technology

After extracting free fatty acids (FFA) from a model crude vegetable oil with methanol, FFA were separated from methanol by nanofiltration. Of the several commercially available membranes that were evaluated, the best resulted in FFA rejection of >90% and flux of >25 Lm⁻²h⁻¹. A combination of high-rejection and low-rejection membranes resulted in a retentate stream of 35% FFA and a permeate stream with less than 0.04% FFA, which can be recycled to the extractor. No alkali is required, no soapstock is formed, and almost all streams within the membrane process are recycled with little discharged as effluent.     

OSCILLATORY STATES AND SLOW ACTIVITY CHANGES DURING THE OXIDATION OF HYDROGEN BY PALLADIUM

Sustained oscillations of the reaction rate were observed during the oxidation of hydrogen on a palladium wire whose temperature was maintained constant by a constant temperature anemometer. This oscillatory behavior was observed only within a region of operating conditions under which the activity of the wire responded very slowly to sudden changes in the limiting reactant's concentration. The slow activity changes and oscillations are probably caused by slow surface oxidation and reduction. The oscillatory states are independent of the linear gas velocity for sufficiently high velocities, indicating that they are not caused by the coupling between chemical and transport rate processes.     

Electrochemical synthesis: a novel technique for processing multi-functional coatings

Electrochemical synthesis is a powerful tool for surface modification, substrate cleaning and formulation of thin films and bulk materials. It is especially suited for surface modification of fibers, metals and films. In the past decade electrochemical method has become the preferred technique for in situ passivation, and coating of commodity metals such as aluminum, zinc, copper and steel.

We have successfully synthesized different kinds of conducting polymers, including polypyrrole (PPy)–polyaniline (PANi) composites. The processability and corrosion performance of PPy/PANi, composite coatings are significantly better than those for either PPy or PANi, coatings.

In this paper, we will discuss the use of electrochemical technique in the synthesis and characterization of multi-functional corrosion resistant conducting polymer coatings for aerospace and automotive applications.     

Effect of blend rheology on the transport property of oriented poly(ethylene terephthalate) blends

Rheological studies were performed to delineate appropriate stretching windows, and poly(ethylene terephthalate)/poly(ethylene-co-vinyl alcohol) blend films were extruded biaxially within such processing windows. The morphology and oxygen permeability properties of these films, with and without a compatibilizer, were characterized. The intent of this study was to achieve a blend oxygen permeability value (OPV) of less than 1. At a fixed draw ratio and draw temperature, appropriate rheological matching could lead to an increase in the aspect ratio of the EVOH phase and, thereby, of oxygen barrier properties. This study concludes that by melt viscosity matching it is not possible to obtain blends with OPV of less than 1. The model of Fricke, used to predict blend permeability, was found to be more accurate at the higher draw temperatures, with the measured values deviating increasingly negatively from the predicted values as the draw temperature is decreased. © 1995 John Wiley & Sons, Inc.     

QoS customization in distributed object systems

Applications built on networked collections of computers are increasingly using distributed object platforms such as CORBA,Java Remote Method Invocation (RMI), and DCOM to standardize object interactions. With this increased use comes the increased need for enhanced quality of service (QoS) attributes related to fault tolerance, security, and timeliness. This paper describes an architecture called CQoS (configurable QoS) for implementing such enhancements in a transparent, highly customizable, and portable manner. CQoS consists of two parts: application‐ and platform‐dependent interceptors and generic QoS components. The generic QoS components are implemented using Cactus, a system for building highly configurable protocols and services in distributed systems. The CQoS architecture and the interfaces between the different components are described, together with implementations of QoS attributes using Cactus and interceptors for CORBA and Java RMI. Experimental results are given for a test application executing on a Linux cluster using Cactus/J, the Java implementation of Cactus. Compared with other approaches, CQoS emphasizes portability across different distributed object platforms, while the use of Cactus allows custom combinations of fault‐tolerance, security, and timeliness attributes to be realized on a per‐object basis in a straightforward way. Copyright © 2003 John Wiley & Sons, Ltd.