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91.
S. Sivanantham M. Padmavathy Ganga Gopakumar P.S. Mallick J. Raja Paul Perinbam 《Integration, the VLSI Journal》2014
In this paper, we present two multistage compression techniques to reduce the test data volume in scan test applications. We have proposed two encoding schemes namely alternating frequency-directed equal-run-length (AFDER) coding and run-length based Huffman coding (RLHC). These encoding schemes together with the nine-coded compression technique enhance the test data compression ratio. In the first stage, the pre-generated test cubes with unspecified bits are encoded using the nine-coded compression scheme. Later, the proposed encoding schemes exploit the properties of compressed data to enhance the test data compression. This multistage compression is effective especially when the percentage of do not cares in a test set is very high. We also present the simple decoder architecture to decode the original data. The experimental results obtained from ISCAS'89 benchmark circuits confirm the average compression ratio of 74.2% and 77.5% with the proposed 9C-AFDER and 9C-RLHC schemes respectively. 相似文献
92.
Martin Wilken Engin Ciftyürek Stefan Cwik Lukas Mai Bert Mallick Detlef Rogalla Klaus Schierbaum Anjana Devi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(1):2204636
The intrinsic properties of semiconducting oxides having nanostructured morphology are highly appealing for gas sensing. In this study, the fabrication of nanostructured WO3 thin films with promising surface characteristics for hydrogen (H2) gas sensing applications is accomplished. This is enabled by developing a chemical vapor deposition (CVD) process employing a new and volatile tungsten precursor bis(diisopropylamido)-bis(tert-butylimido)-tungsten(VI), [W(NtBu)2(NiPr2)2]. The as-grown nanostructured WO3 layers are thoroughly analyzed. Particular attention is paid to stoichiometry, surface characteristics, and morphology, all of which strongly influence the gas-sensing potential of WO3. Synchrotron-based ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), X-ray photoelectron emission microscopy (XPEEM), low-energy electron microscopy (LEEM) and 4-point van der Pauw (vdP) technique made it possible to analyze the surface chemistry and structural uniformity with a spatially resolved insight into the chemical, electronic and electrical properties. The WO3 layer is employed as a hydrogen (H2) sensor within interdigitated mini-mobile sensor architecture capable of working using a standard computer's 5 V 1-wirebus connection. The sensor shows remarkable sensitivity toward H2. The high, robust, and repeatable sensor response (S) is attributed to the homogenous distribution of the W5+ oxidation state and associated oxygen vacancies, as shown by synchrotron-based UPS, XPS, and XPEEM analysis. 相似文献
93.
Priyanka U. Londhe Ashwini B. Rohom Ganesh R. Bhand Sujata Jadhav Manorama G. Lakhe Nandu B. Chaure 《Journal of Materials Science: Materials in Electronics》2017,28(7):5207-5214
Zinc sulfide (ZnS) thin films have been deposited onto fluorine doped tin oxide and microscopic glass substrates from an aqueous alkaline reaction by chemical bath deposition. The effect of concentrations of hydrazine hydrate (HyH) (complexing agent) on the deposit is studied. X-ray analysis confirm the growth of nanocrystalline ZnS thin films with reflections (111), (220) and (311) correspond to cubic crystalline phase. TEM results support the growth of cubic ZnS layers. The energy band gap was successfully tailored from 2.77 to 3.80 eV. Photoluminescence study indicates a strong band-edge emission with some defect like vacancies. It was also noticed that HyH plays an important role on the nucleation. The remarkable improvement in the growth rate of ZnS thin films have been observed upon increasing the contents of HyH. Nearly stoichiometric ZnS layer was obtained upon annealing prepared with 2.5 M HyH. The crystallinity was found to be increased upon annealing the layers. The ideality factor for the ZnS layers prepared with 0 and 1.0 M HyH were obtained?~1.71 and 1.24, respectively. The capacitance–voltage plots behave according to Schottky–Mott theory. The doping concentrations?~1017 and 1018 cm?3 were calculated for the layers deposited with 0 and 1.0 M HyH, respectively. 相似文献
94.
Ashis Mallick Rajiv Ranjan Dilip K. Prasad 《Inverse Problems in Science & Engineering》2019,27(7):969-986
This paper presents an inverse study of heat transfer of a conductive, convective and radiative annular fin made of a functionally graded material. Three major parameters such as conductive–convective parameter, conductive–radiative parameter and the parameter describing the variation of thermal conductivity are inversely estimated from a specified temperature field. The forward solution of temperature field is obtained from the closed form solution of nonlinear heat transfer equation using Homotopy perturbation method (HPM). A dragonfly algorithm that simulates the swarming behaviour of dragonflies, as analogous, is employed in finding out the inverse parameters. The temperature values of the forward solution are used as input data for the inverse analysis. The inverse parameters are then estimated iteratively by minimizing the objective function until the guessed temperature field approximately satisfies the preassigned temperature field of the forward solution. The inverse simulation following HPM-based forward solution converges faster than ordinary differential equation-based forward solution. The reconstructed temperature fields obtained from the various combination of inverse parameters give good agreement (~1% error) with the desired temperature field. Thus, the presented inverse model provides an opportunity to the fin designer for selecting the several feasible combinations of thermal parameters suggesting the material design that result in a prescribed temperature field. 相似文献
95.
Harris Martyn R. Finch John W. Mallick John A. Miller Timothy J. E. 《Industry Applications, IEEE Transactions on》1986,(4):716-721
An evaluation of the capabilities of the switched reluctance (SR) motor drive, particularly in small integral-horsepower sizes, is presented, and some of its special features are discussed. The simplicity of the construction of the rotor together with certain advantages in the power circuit, such as unipolar operation and the independence of the phases, are described along with some of the important performance parameters, which are compared with those of typical induction motor drives. It is shown that the ruggedness and simplicity of the SR drive are accompanied by a performance profile that matches that of modern induction motor drives in torque per unit volume, efficiency, converter voltampere requirements, and other parameters. A comparison of three SR motors, including one low-inertia design and one with two stator teeth per pole, shows torque/inertia ratios several times greater than those for induction motor drives. 相似文献
96.
97.
Analysis of sorption/desorption and diffusion kinetics of ketones and nitriles at 25, 44, and 60°C into three Du Pont's VITON fluoropolymer membranes loaded with different amounts of carbon black has been undertaken by use of a sorption/desorption technique. The transport results are affected by the percent loading of carbon blacks. Diffusion coefficients have been calculated from Fick's equation. These results show a decrease with increasing amount of carbon black. Experimental results have been analyzed by considering swelling of the membranes. Sorption/desorption results have been analyzed from a calculation of the concentration profiles, which are obtained from the analytical solution of Fick's equation. These results have been compared with a numerical solution based on the finite difference method. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 635–647, 1997 相似文献
98.
Molecular transport of organic liquids into Viton fluoropolymers has been investigated by a sorption—desorption gravimetric method. Diffusion coefficients have been calculated from Fick's equation. The sorption—desorption results have been used to calculate the concentration profiles by solving Fick's diffusion equation under suitable boundary conditions. A numerical method based on the finite difference technique was also used to calculate the concentration profiles of liquids as a function of sorption time and thickness of the Viton fluoropolymers. The dependence of sorption, desorption, diffusion, and permeation properties of the liquids on temperature showed a significant effect. The Arrhenius activation parameters have been estimated for diffusion, permeation, and sorption processes. The experimental and calculated results are discussed to study the type and nature of interactions between Viton fluoropolymers and the solvent molecules. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 717–723, 1997 相似文献
99.
This paper discusses the static and fatigue behavior of adhesively bonded single lap joints in SMC-SMC composites. Effects of lap length and adhesive thickness on the static and fatigue strength of SMC-SMC adhesive joints are studied. Effects of SMC surface preparation and test speed on the joint performance are evaluated. Finally, the effect of water exposure on the joint durability is also investigated. Results show that the static behavior of adhesive joints in SMC-SMC composites is significantly influenced by the lap length and adhesive thickness. With an increase in lap length from 12.7 mm to 38.1 mm, the joint failure load increases by 37%. The joint failure load also increases with the adhesive thickness, but it reaches a maximum at an adhesive thickness of 0.33 mm and then decreases. However, lap length and adhesive thickness have negligible effect on the ratio of fatigue strength to static strength. The fatigue strength at 106 cycles is approximately 50% to 54% of the static strength for various adhesive thicknesses and lap lengths investigated in this study. Adhesive failure, fiber tear or combination of these two failure modes are observed during both static and fatigue tests. 相似文献
100.
Tejraj M. Aminabhavi Sujata F. Harlapur Ramachandra H. Balundgi J. Dal Ortegoe 《应用聚合物科学杂志》1996,59(12):1857-1870
Sorption kinetics and diffusion of hexane, heptane, octane, nonane, decane, cyclohexane, and 2,2,4-trimethylpentane through tetrafluoroethylene/propylene copolymer membranes were studied using the gravimetric sorption method at 30, 45, and 60°C. Coefficients of diffusion were calculated from Fick's equation. From these data, the permeability coefficients were obtained. Analytical solutions of Fick's relations were used to estimate the liquid concentration profiles into the polymeric membranes at different times. The profiles of liquid concentrations were also simulated for the polymer–solvent systems using the numerical simulation method. Activation parameters for diffusion and sorption were evaluated and these results are discussed in terms of the molecular sizes and geometries of liquids (i.e., shape) as well as temperature. The diffusion coefficients follow a systematic decrease with increasing size of the penetrant molecules. The activation energies i.e., ED values, increase with increasing size of n-alkanes. © 1996 John Wiley & Sons, Inc. 相似文献