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In this paper, a novel image steganography approach is proposed to enhance the visual quality of stego image. The cover image is decomposed using Discrete Wavelet Transform (DWT) to produce wavelet subbands and threshold value is calculated for each higher frequency wavelet subbands. Wavelet coefficients having magnitude larger than the threshold of its subband are selected to embed the secret data. Semi Hexadecimal Code (SHC) is proposed to convert pixel value of secret image into smaller equivalent value so that it distorts stego image as less as possible. Experimental results shows that maximum PSNR between cover image and stego image is more than 75 dB .Proposed approach is also compared with the existing approaches and this comparison shows that the proposed approach is better than the existing approaches.

A finite element model is constructed to analyze the effects of steady state temperature field on FGM layer thickness. The first-order shear deformation model is exploited to investigate the uncoupled thermal behavior of functionally graded plates in Abacus environment. The continuum is divided into 540 elements and 541 nodes using two node linear elements. The results show that the temperature distribution in the composite plate is more reasonable with increase in the thickness of FGM layer. The comparison with the non-graded two layered composite plate, the temperature field of the Zirconia/FGM/Aluminum three layered composite plate is in the form of a curve but in case of non-graded two layered composite plate the temperature field is in the form of inclined straight line with sharp bend at the interface of metal and ceramic phase.

A closed loop speed control scheme for a Permanent Magnet Brushless DC (PMBLDC) motor is implemented using single current sensor without position and speed sensors. The rotor position information is derived from the back emf of the motor and this in turn is used for determining the rotor speed. The various aspects of DSP based closed loop speed control (such as derivation of position, current sensing, speed controller and PWM generation) of the PMBLDC drive system are discussed. The DC link Current is sensed for feedback, which reduces the requirement of current sensor and hence limits the overall cost of the drive system.

This paper presents the performance analysis of interior permanent magnet synchronous motor (IPMSM) fed from improved power quality converter–inverter system as a variable speed drive for air-conditioning (Air-Con). The improved power quality converter (IPQC) makes the input power factor unity and also reduces the total harmonic distortion (THD) of input supply current. This converter consists of two uncontrolled unidirectional and two bi-directional switches. It provides constant DC-link voltage during transient and steady state conditions. This converter has high efficiency as only two switches conduct at a time and IPMSM also offers high efficiency as compared to other electric motors. The proposed drive system is an appropriate solution for energy conservation in the AC distribution system, in the motor and in the compressor of Air-Con. The detailed model and the simulated results of the proposed drive system are presented to demonstrate the features of improved power quality and energy conservation.

Based on results from a measurement of weak decay branches observed following the β- decay of 94Y and on lifetime data from a study of 94Zr by inelastic neutron scattering, collective structure is deduced in the closed-subshell nucleus 94Zr. These results establish shape coexistence in 94Zr. The role of subshells for nuclear collectivity is suggested to be important.

Geriforte, an herbomineral compound prepared from several herbs and minerals, is being used as a restorative tonic to solve the problems of old age in India. Since active oxygen species have been proposed to be involved in the aging process of the brain, alterations in the level of enzymes involved in the defense system against free radicals and other active oxygen species could substantially influence the aging process. Therefore, in the present study, this antistress adaptogenic Ayurvedic preparation has been evaluated for the activities of superoxide dismutase (SOD) and catalase (CAT), key enzymes of the cellular defense system, in the brain of aging Wistar male rats. The present study was carried out on 22-month-old rats. They were given Geriforte powder orally at a dosage of 900 mg/kg body weight once a day for two months. The Geriforte-treated rat brain had significantly high levels of SOD and CAT activities than those recorded in their respective controls. The contents of SOD and CAT in Geriforte-administered brain increased by 24% and 30%, respectively. In the present investigation, free radical damage was assessed by measuring thiobarbituric acid reactive substance (TBARS) in postmitochondrial fractions of brain homogenate. The magnitude of TBARS has been reported to be decreased by 26% in the Geriforte-treated rat brain. In conclusion, it seems logical to suppose that Geriforte, a combination of several plant ingredients and minerals, protects the body against the damaging effects of free radicals by producing large amounts of antioxidant enzymes.

Agro residues, a precious source of nutrients are being disposed off because of their bulky nature and non-availability of management practices. Besides loss of essential plant nutrients and organic matter important for sustainability of the system, it also causes environmental pollution leading to animal and human health problems. It is important to recycle these crop residues for restoring soil health and sustainability of the production system for national food and nutritional security. Composting can be adopted for large scale recycling of these agrowastes to enriched compost using efficient microorganisms. Apart from being a source of nitrogen, phosphorus, potassium, and other nutrients for plants, compost is also believed to suppress soil-borne diseases in plants. These virtues make composting an ideal option for processing the enormous quantities of agro wastes that are generated in the world. Besides this agrowastes may be utilized as a resource for production of animal feed, biofuel and enzyme to generate additional income.

Gamma-ray angular distribution measurements following the {sup nat}Ni(n,n{sup '}{gamma}) reaction were carried out at 1.6 and 1.8 MeV neutron energies. Through the Doppler-shift attenuation method, the lifetime of the 2{sub 1}{sup +} state in {sup 58}Ni is determined as {tau}=1.00{sub -0.10}{sup +0.15} ps, which yields a B(E2;2{sub 1}{sup +}{yields}0{sub 1}{sup +}) value of 9.4{sub -1.2}{sup +1.0} W.u. From previous measurements and this work, average values of {tau}=0.94(3) ps and B(E2;2{sub 1}{sup +}{yields}0{sub 1}{sup +})=10.0(4) W.u. are recommended as standards for normalization. In addition, a longer lifetime of {tau}=1.30{sub -0.20}{sup +0.30} ps has been determined for the 2{sub 1}{sup +} state in {sup 60}Ni, which yields an E2 strength of 10.7{sub -2.5}{sup +1.7} W.u. Our results support an enhancement of proton-core excitations and related quadrupole and pairing strengths in the light Ni isotopes, in agreement with mean-field and shell-model calculations.

This paper presents the fuzzy pre-compensated PI (FPPI) speed controller for permanent magnet brushless DC (PMBLDC) motor drive. Various aspects of DSP based implementation of PMBLDC motor drive system such as inverter, position and current sensing, reference current generation and PWM current control are discussed in detail. The fuzzy logic algorithm used in this work particularly suitable for digital control because of the simplified way of handling the rule base and considerable reduction of computation during defuzzification process. Transient performance of the drive system obtained using FPPI speed controller is compared with the conventional PI speed controller.

This paper presents important experimental findings on a novel 2-winding single phase self-excited induction generator (SEIG) through extensive experimentation. The performance of the generating unit has been critically evaluated in terms of voltage, frequency consistency, efficiency and sensitivity to realistic parameters. These results are expected to assess its suitability for practical application towards standby power generation. These results would guide on the needed requirements in the system.

This paper deals with the design and development of a photovoltaic (PV) array fed cage induction motor for an isolated water pumping system. A drive system using a chopper circuit to track power from the PV for different solar and a current controlled voltage source inverter (CC-VSI) to optimally match the motor to PV characteristics is presented. The model equations governing interaction of torque and flux producing components of motor current with available solar power is developed for the operation of the system at optimum efficiency. Performance of the system is presented for different realistic operating conditions, which demonstrates its special features for applications such as solar water pumping system, solar vehicles and flour mills located in hilly and isolated areas,.

This paper describes an experimental study carried out on a permanent magnet brushless DC (PMBLDC) motor drive coupled to a pump load powered by a photovoltaic (PV) array for water pumping system applications. A simple low-cost prototype controller has been designed and developed without current and position sensors which drastically reduces the overall cost of the motor drive system. This controller is used to test the dynamic behavior of the PMBLDC motor drive system. A mathematical model of the system is developed with a view to carrying out a comparison between the experimental and simulated response of the drive system. The necessary computer algorithm is developed to analyze the performance under different conditions of varying solar insolation for a pump load. The developed state-space equations are simulated to obtain the performance characteristics which are also verified by conducting a suitable experiment on the developed PV pumping system.

This paper deals with the reduction of overall cost of a current controlled voltage source inverter fed vector controlled induction motor drive (VCIMD). For this purpose an attempt has been made here to examine the possibility of such elimination/reduction in the number of sensors. The performance analysis of the VCIMD system (22 kW cage induction motor) is carried out and with the help of simulated results the effectiveness of the proposed elimination/reduction of sensors is assessed.

This paper deals with the power quality improvement of AC mains in Direct Torque-Controlled (DTC) permanent magnet synchronous motor (PMSM) drive using active wave shaping techniques. For this purpose, different topologies for active wave shaping of AC mains current in DTC-based PMSM drive such as single- and two-switch boost power factor correction (PFC) AC-DC converter, asymmetrical two-switch boost PFC AC-DC converter and single-phase voltage source AC-DC converter (VSC) are considered. The models are developed and simulated in MATLAB environment along with the Power System Blockset (PSB) and Simulink toolboxes to compute the relevant power quality performance indices. The simulated results demonstrate the effectiveness of different topologies in improving the power quality of the input AC mains in DTC-based PMSM drive.

The paper examines the dynamic response of the static synchronous series compensator (SSSC) with sliding-mode and fuzzy controllers. A current-controlled voltage-source inverter (CC-VSI) is used as an SSSC. It injects a sinusoidally varying voltage (0

The issues involved in the design of energy-efficient high-performance irrigation pump induction motors operating under typical field conditions are highlighted. Various factors deserving consideration, from the predesign survey to the final design stage, are discussed in detail. By resorting to optimisation techniques, suitable objective functions were evolved to arrive at an improved design, which is constrained by industrial practices and performance requirements. The new design is compared with the standard design, and its salient features are discussed to suggest useful guidelines.

This paper describes the technique for cross-linking cellulose with formaldehyde in the vapor and liquid phases. It also gives a brief description of an improved method for estimating the degree of cross-linking. Moisture sorption isotherms of cross-linked samples have been obtained at different relative humidities ranging from 0 to 90% and at 25°C by using McBain-Bakr sorption balance. The relationship between swelling and water content in the bath is nonlinear. This may be due to unrestricted swelling at the lower concentrations of water in the bath; in the intermediate range of water concentrations, the swelling does not increase significantly because of primary-wall constraint. Moisture regain of the control samples increases with increase in swelling up to 16%. This change is more pronounced at higher humidities. However, for 19% swelling, possibly because of the breaking of the primary wall, the cellulose chains may so rearrange themselves that hydrogen bonding between OH-groups increases, thereby decreasing the moisture regain. Swollen samples are stabilized by cross-linking. The moisture sorption characteristics of cross-linked swollen samples depend on the degree of swelling at the time of cross-linking and also on the degree of cross-linking.

Moisture sorption data of Form C samples have been obtained using a McBain-Bakr sorption balance and these were used to calculate effective area of molecular contact of the cross-linked samples with the Brunauer-Emmet-Teller (BET) equation. A probable explanation is advanced for the maxima and minima in moisture regains of cross-linked in the swollen state samples and the effective area/HCHO relationship. Attempts have been made to infer the distribution of cross-links trom the moisture sorption data of the cross-linked samples. Iodine accessibility values of formaldehyde-crosslinked fibre and dye pickup studies of formaldehyde-crosslinked fabric support an earlier assumption that the primary wall is ruptured under Form W conditions.