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1.
The Arithmetic and Logic Unit (ALU) is a combination circuit that performs a number of arithmetic and logical operations within a microprocessor. The demand for faster and compact ALUs makes it desirable to test the ALU in conjunction with pre-design parts prior to manufacture. This may be accomplished in a process using CAD and SPICE simulation software. Our purpose is to realize a method for importing a layout drawn in Tanner L-edit and simulated in T-Spice into PSpice which is referred to as software talking. To do so we use an eight-function instruction set called Complimentary Metal Oxide Semiconductor Arithmetic and Logic Unit (CMOS ALU) which is laid out in Tanner L-edit and produces an extracted net-list which is simulated in T-Spice. An ALU equivalent design is then modeled in PSpice for further testing with pre-manufactured parts of the PSpice library.  相似文献   
2.
The influence of dendritic crystallization on the structure and properties of continuous-cast pipe blanks (diameter 150 mm) made from steel with 0.2% C is studied, in the cast and heat-treated states. Dendritic crystallization results in different chemical composition of the austenite and the boundary between the crystals, with different properties. That affects the structure of the steel. Besides the familiar factors, the improvement in the mechanical properties of cast subeutectoid steel after heat treatment is associated with the formation of impurity-rich ferrite in segregated sections of the dendritic structure.  相似文献   
3.
The spectrum of this survey turns on the evaluation of some eminent Riemann solvers (or the so-called solver), for the shallow water equations, when employed with high-order Runge–Kutta discontinuous Galerkin (RKDG) methods. Based on the assumption that: The higher is the accuracy order of a numerical method, the less crucial is the choice of Riemann solver; actual literature rather use the Lax-Friedrich solver as it is easy and less costly, whereas many others could be also applied such as the Godunov, Roe, Osher, HLL, HLLC, and HLLE. In practical applications, the flow can be dominated by geometry, and friction effects have to be taken into consideration. With the intention of obtaining a suitable choice of the Riemann solver function for high-order RKDG methods, a one-dimensional numerical investigation was performed. Three traditional hydraulic problems were computed by this collection of solvers cooperated with high-order RKDG methods. A comparison of the performance of the solvers was carried out discussing the issue of L1-errors magnitude, CPU time cost, discontinuity resolution and source term effects.  相似文献   
4.
We present the results of molecular dynamics simulations of PEOxNaI polymer electrolytes, performed to study the influence of NaI on the dynamics of PEO. By calculating the mean square displacement of the CH2 groups we observe that the Rouse-like motion, typical for short polymer chains, is slowed down under the influence of NaI. This slowing down is also observed in the self part of the intermediate scattering function Fs(k,t), as an increase in the relaxation time. By using the Gaussian approximation it is shown that the stretched exponential relaxation in the small k-limit of Fs(k,t) is a result of the Rouse-like motion of the polymers. We find that our results are in good agreement with neutron spin-echo experiments.  相似文献   
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6.
In the present paper, we analyze the role of in situ grown BaZrO3 (BZO) inclusions in YBa2Cu3O7?x (YBCO) thin films prepared by chemical solution deposition using a low fluorine coating solution, on the field angle dependence of the critical current density, J c (??), data using the vortex path model. In order to form a coherent picture on the BZO doping influence on the pinning properties of the YBCO matrix, detailed structural analyses performed by X-ray diffraction techniques and microstructural evaluation by transmission electron microscopy are also presented. The evaluation of different contributions to the overall, J c , permitted us to prove the effectiveness of the BZO inclusions acting as isotropic pinning centers, reflected in a uniform component of high relative value with respect to other components. For the studied 10 mol % BZO doping concentration, a threefold increase in the critical current density, J c , of the YBCO host is measured, in self-field at 77 K, corresponding to a value of J c =2.9MA/cm2, whereas a factor 10 is measured at 1 T (J c =0.35 MA/cm2).  相似文献   
7.
Sulfolobus solfataricus protein disulphide oxidoreductase (SsPDO)contains three disulphide bridges linking residues C41XXC44,C155XXC158, C173XXXXC178. To get information on the role playedby these cross-links in determining the structural and functionalproperties of the protein, we performed site-directed mutagenesison Cys residues and investigated the changes in folding, stabilityand functional features of the mutants and analysed the resultswith computational analysis. The reductase activity of SsPDOand its mutants was evaluated by insulin and thioredoxin reductaseassays also coupled with peroxiredoxin Bcp1 of S. solfataricus.The three-dimensional model of SsPDO was constructed and correlatedwith circular dichroism data and functional results. Biochemicalanalysis indicated a key function for the redox site constitutedby Cys155 and Cys158. To discriminate between the role of thetwo cysteine residues, each cysteine was mutagenised and thebehaviour of the single mutants was investigated elucidatingthe basis of the electron-shuffling mechanism for SsPDO. Finally,cysteine pK values were calculated and the accessible surfacefor the cysteine side chains in the reduced form was measured,showing higher reactivity and solvent exposure for Cys155.  相似文献   
8.
The present paper proposes a modified version of the Manufacturing cost deployment (MCD) method to analyse engineer-to-order (ETO) production systems. The novel approach, named Project cost deployment (PCD), introduces two substantial and innovative modifications. To begin with, the concept of manual assembly macro-activity replaces the traditional concept of station. Then, a brand-new structure for classifying and analysing losses is introduced, that is specifically defined to deal with the inefficiencies of the manual assembly tasks. The validity of the approach is proved by a real-world industrial application. The obtained results demonstrate that the PCD method allows the analyst to identify the hidden losses and to quantify the wastes from an economical point of view. In addition, PCD permits to estimate the impacts of potential (lean) improvement activities and projects in terms of both efficiency and effectiveness.  相似文献   
9.
A numerical solution of the two-dimensional Saint Venant equations is presented for the study of the propagation of the floods through the crossroads of the city. The numerical scheme is a Runge-Kutta discontinuous Galerkin method (RKDG) with a slope limiter. The work studies the robustness and the stability of the method. The study is organized around three aspects: the prediction of the water depths, the location of the right and oblique hydraulic jumps in the crossing, and especially the distribution of the flow discharges in the downstream branches. The objective of this paper was to use the RKDG method in order to simulate supercritical flow in crossroads and to compare these simulations with experimental results and to show the advantage of this RKDG method compared to a second-order finite-volume method. A good agreement between the proposed method and the experimental data was found. The method is then able to simulate the flow patterns observed experimentally and to predict accurately the water depths, the location of the hydraulic jumps, and the discharge distribution in the downstream branches.  相似文献   
10.
The paper deals with a waveguide-coaxial microwave-frequency module capable of exciting a torch microwave discharge in air at the end of single-wire Goubau line. The properties of this discharge are described, as well as its possible uses for applying fine-structure films of refractory materials to substrates. The surface pattern of propagation of microwave energy along the single-wire line in the form of plasmon-polaritons is experimentally supported.  相似文献   
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