Archives-November 2011

Anredera cordifolia (Tenore) Steenis is reported for the first time from India. It is presented here with updated nomenclature, brief description, notes on distribution for better understanding.

In the present work, an effort has been made to investigate the effect of welding parameters on bead geometry. Mathematical models were developed by using 2- level half factorial technique to predict the bead geometry within the range of control parameters or operating variables for single wire submerged are welding. The models developed can be employed easily in automatic or robotic welding, in the form of program, for obtaining the desired high quality welds. Current, open circuit voltage, welding speed and nozzle-to-plate distance were taken as welding variables constant. The models were developed from the observed values, with the help of design matrix.  It was found that penetration increases significantly with current, decreases with welding speed and remains unaffected by open circuit voltage & nozzle to plate distance. Reinforcement was found to increase with current and decrease with open circuit voltage, welding speed and there is no effect by nozzle to plate distance. Weld bead width was found to increase with open circuit voltage, decrease with welding speed; but ‘w’ increases with increase in nozzle to plate distance. The adequacies of the models were tested by use of analysis of variance technique and signification of coefficients was tested by student’s-test’. The combined and main effect of different parameters involved has been presented in graphical form.

Reversible logic is suitable for the design of various logics, functions which indeed has lower power consumption and improved speed. In this research work the testable reversible realization of multiplexers, demultiplexers, flip flops and shift registers is done using new testable reversible gate (NTG), which combines feynman gate and Haghparast Navi Gate (HNG). The flip flops are the basic element for any sequential circuit design. The various flip flops are designed using the reversible logic with the appropriate combination and are used as base element for the design of shift registers. The results from the proposed testable reversible multiplexers and demultiplexers show the 10% reduction in power and also 2% delay improvement as compared to Rgate reversible logic. The sequential elements i.e. flip flops and registers using proposed method show 10% power reduction and 5% speed improvement as compared to designs using Rgate logic. A single unit of combinational and sequential logic is designed for delay and power improvement, practically this can be utilized in the large designs to reduce power consumption and delay to a considerable value. Reversible logic is becoming more and more prominent as the technology sets higher demands on heat, power, scaling and stability. Currently, computations are commonly irreversible, even though the physical devices that execute them are fundamentally reversible.

The aim of the present study is the development of an ecofriendly approach to treat sewage or industrial waste containing metal contaminants. The approach utilized cyanobacterial strain “Anabaena variabilis”, raised using exposure to externally applied electricity. Experimental algal cells were used to test for Copper sorption experiments, which were carried out as a function of pH, initial amount of biosorbtant and contact time. At pH 6 the maximum Cu sorption efficiency of live 1g (20.55%), 3g (34.28%) and 5g (51.43%) test sample were observed after 24 hours. Further studies showed a sharp increase in Cu sorption at the end of 4^th day incubation. At the end of 4^th day uptake of copper ions were found to be maximum for 1g (39.74%), 3g (55.47%) and 5g (71.62%) of test cells. Such findings show the possibility of manipulating or over expressing existing resistance mechanisms and the use of such organisms to remove harmful metals from the environment.

In this study aqueous extract of the leaves of Aerva lanata Linn., Calotropis gigantea Linn. and Elaeocarpus ganitrus Roxb were screened for the haemolytic activity towards human erythrocytes. The haemolytic activity was performed by modified spectroscopic method at four different concentrations (125, 250, 500, 1000 ?g/ml). The haemolytic activity of the different extracts was found in the following order: C. gigantea > A. lanata : C. gigantea (1 :1) > C. gigantea: E. ganitrus (1 : 1) > A. lanata : C. gigantea : E. ganitrus (1 : 1 : 1) > A. lanata : E. ganitrus (1 : 1) > A. lanata. However, all the extracts alone and in combination with each other exhibited very low haemolytic activity. E. ganitrus did not exhibit any haemolytic activity at any dilution. Hence, they can be considered as safe to human erythrocytes.

'The start of new century may have seen a decline in the number of incidents of 'traditional' terrorism such as hijackings and kidnappings but the lethality of the terrorist potential has risen to a frightening degree with the advent of digitalized terrorism , and its links to computer technology. The vulnerability of the critical infrastructure has led to increasing concern that it will be the target of terrorist attacks. In this highly topical study the authors examine the new terrorist tools and their appalling capacity for the destruction of human systems. The authors claim that the technological revolution has effectively 'democratized' computer knowledge so that the forces of law and order no longer have an inherent advantage of power and privilege. Their special challenge in the new century will be to match the resourcefulness and ingenuity of their terrorist adversaries. The purpose of this paper is to explore how the Internet is altering the traditional concept of terrorism. What are the common Ways of terrorists attacks Cyber-terrorism or digitalized terrorism is a catastrophic phenomenon that has not yet attracted the attention of the Indian Legislature exhaustively. The paper consider whether there is a need to react to digitalized terrorism and if so, to what extent?

Steganography is a captivating area of research in the new modern world. Steganography is a form of covert communication in which a secret message is invisible within a carrier message. Various image Steganography techniques have been proposed. The user data should be made secret in order to have the user’s privacy and security. This novel algorithm represents the encryption and decryption of medical data of the patient and the patient’s medical image using LSB and chaotic systems. In this paper, investigate diverse Steganography techniques and tools. The chaotic signal generation and the result analysis are done by using the Matlab 7.10.

Azeotropic distillation is a special case of multicomponent distillation used for separation of binary mixtures which are either difficult or impossible to separate by ordinary fractionation. The work is mainly focus on the separation of azeotropic mixtures. Selection of solvent plays an important role in industry to break the azeotropes in easy way. The solvent is selected in such a way that it should break the azeotropic mixture and also should form azeotropic mixture with one of the original component. Determining the existence of homogeneous azeotropes together with their composition, temperature and pressure is important from both theoretical and practical standpoints in the analysis of phase behavior and in the synthesis and design of separation system employing distillation. Different moles of solvent are added to the existence composition of azeotropic mixtures at constant temperature and pressure. Raoult’s law is taken in the modeling to get vapor mixture from given liquid mixture calculated after addition of the solvent to the original azeotropic mixture.

Polymeric insulating materials are increasingly being used in outdoor and radiation environments such as space, nuclear power plants etc. It is well known that polymeric materials used for electrical insulations may suffer from tracking. It is necessary to form a credible database about the tracking resistance of different polymeric insulating materials and their behaviour under ac/dc voltage stresses as affected by the radiation. The investigations here show that, the DC resistance to tracking of all the materials investigated were significantly lower than that for AC. It is therefore necessary to formulate separate standards for tracking under DC voltage stresses. Also, the test results show that Silicone rubber and High Density Poly Ethylene samples are reliable for radiation environments.

The entomopathogenic fungus Beauveria bassiana is a promising biocontrol agent against coffee berry borer, Hypothenemus hampei in coffee. The fungus conidial survival was influenced by both environment and agrochemicals normally used to protect crop plants. The present study evaluates the fungitoxic effect of commonly used chemical insecticides (endosulfan, chlorpyriphos, dimethoate and quinalphos) and fungicides (bordeaux, hexaconazole and triadimefon) on germination, vegetative growth and sporulation of B. bassiana. The insecticides and fungicides were tested at three concentrations (Field Recommendation (FR), half FR, and twice FR). All the tested concentrations inhibited the germination (9.0-81.19% and 19.3-100%), vegetative growth (0.5-62.9% and 37.1-100%) and sporulation (7.0-99.9% and 99-100%) of B. bassiana by the insecticides and fungicides respectively, but dimethoate exhibited minimum inhibitory effect. Dimethoate showed better compatibility to B. bassiana in all the three concentrations. As dimethoate is safer to biological control agent, could be used as an integrated pest management in coffee.