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Diep  T.A. Shen  J.P. 《Computer》1995,28(12):57-64
Superscalar processor design requires increasingly sophisticated software tools. The visualization-based microarchitecture workbench described in the paper addresses weaknesses common to most performance simulators: the lack of retargetability, visualization support, and interactive control. VMW provides a multifunction workbench for aiding designers of modern superscalar processors. It facilitates rigorous machine specification by providing specification templates at both the architecture and microarchitecture levels  相似文献   
3.
Twelve silages were prepared from uncooked or cooked lizard fish (Saurida undosquamis) and blue crab (Portunus pelagicus) and stored at ambient temperature (30 ± 2 °C) for 60 days. The antioxidative effect of adding ethoxyquin was also investigated. Generally, the nutritional quality of all the silages was stable for up to 60 days of storage and the composition of raw materials was reflected in the composition of the silages. Crab had a lower level of crude protein than fish (85 versus 162 mg kg?1), but a higher level of ash (96 versus 36 g kg?1); moreover, there were significant differences in nutritional composition between uncooked and cooked materials. High level of ash in crab required addition of high levels of formic acid in crab‐related silages. At the end of the experiment cooked silages showed a tendency for spoilage; in particular, maggots were observed in cooked crab silages on the last few days of the experiment. Comparison of treatments with or without ethoxyquin showed that only rancidity of fish silage groups was higher without addition of ethoxyquin. Uncooked materials are more suitable for prolonged storage than cooked materials, and it is probably not necessary to add antioxidants to silages made from material with low lipid content. Copyright © 2009 Society of Chemical Industry  相似文献   
4.
An understanding of how software is employed in the field can yield many opportunities for quality improvements. Profiling released software can provide such an understanding. However, profiling released software is difficult due to the potentially large number of deployed sites that must be profiled, the transparency requirements at a user's site, and the remote data collection and deployment management process. Researchers have recently proposed various approaches to tap into the opportunities offered by profiling deployed systems and overcome those challenges. Initial studies have illustrated the application of these approaches and have shown their feasibility. Still, the proposed approaches, and the tradeoffs between overhead, accuracy, and potential benefits for the testing activity have been barely quantified. This paper aims to overcome those limitations. Our analysis of 1,200 user sessions on a 155 KLOC deployed system substantiates the ability of field data to support test suite improvements, assesses the efficiency of profiling techniques for released software, and the effectiveness of testing efforts that leverage profiled field data.  相似文献   
5.
Diep Vu Ca 《Electrochimica acta》2006,51(11):2188-2194
Gold and platinum nanoparticles (NPs) were prepared by chemical reduction of the corresponding metal complex bound by ion-exchange to generation-4 poly(amidoamine) dendrimers (PAMAM). Arrays of the NPs on indium tin oxide (ITO) electrodes were formed by adsorbing a monolayer comprising a controlled ratio of NP-PAMAM to PAMAM on ITO that was modified with 3-aminopropyl triethoxysilane; subsequently, the organic components were thermally destroyed. Varying the above-defined ratio resulted in a commensurate change of the density of the NPs on the surface. Using an electrode modified in a solution with a mole fraction of Au-PAMAM (relative to total of Au-PAMAM and PAMAM) of 0.06, which gave NPs separated by 200 nm, the current for the catalytic oxidation of cysteine reached a value that did not increase when more nanoparticles were present. The analogous experiment on the oxidation of AsIII with PtNPs as the catalyst was optimized at a mole fraction of 0.2. Calculations assuming hemispherical diffusion suggested that the diffusion domains during cyclic voltammetry at 5 mV s−1 were less than the distance between the NPs.  相似文献   
6.
A novel actuator system which has achieved increased popularity to provide these advantages such as high strength and power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available, cheap power source, inherent safety and mobility assistance to humans performing tasks has been the utilization of the pneumatic artificial muscle (PAM) manipulator, in recent times. However, the complex nonlinear dynamics of the PAM manipulator makes it a challenging and appealing system for modeling and control design. The problems with the time variance, compliance, high hysteresis and nonlinearity of pneumatic systems have made it difficult to realize precise position control with high speed. In order to realize satisfactory control performance, the effect of nonlinear factors contained in thePAM manipulator must be considered. The purpose of this study is to improve the control performance of thePAM manipulator using a nonlinearPID controller. Superb mixture of conventionalPID controller and the neural network, which has powerful capability of learning, adaptation and tackling nonlinearity, brings us a novel nonlinearPID controller using neural network. This proposed controller is appropriate for a kind of plants with nonlinearity uncertainties and disturbances. The experiments were carried out in practicalPAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through the experiments, which suggests its superior performance and disturbance rejection.  相似文献   
7.
Do DB  Lin JH  Lai ND  Kan HC  Hsu CC 《Applied optics》2011,50(23):4664-4670
We demonstrate the fabrication of a three-dimensional (3D) polymer quadratic nonlinear (χ(2)) grating structure. By performing layer-by-layer direct laser writing (DLW) and spin-coating approaches, desired photobleached grating patterns were embedded in the guest-host dispersed-red-1/poly(methylmethacrylate) (DR1/PMMA) active layers of an active-passive alternative multilayer structure through photobleaching of DR1 molecules. Polyvinyl-alcohol and SU8 thin films were deposited between DR1/PMMA layers serving as a passive layer to separate DR1/PMMA active layers. After applying the corona electric field poling to the multilayer structure, nonbleached DR1 molecules in the active layers formed polar distribution, and a 3D χ(2) grating structure was obtained. The χ(2) grating structures at different DR1/PMMA nonlinear layers were mapped by laser scanning second harmonic (SH) microscopy, and no cross talk was observed between SH images obtained from neighboring nonlinear layers. The layer-by-layer DLW technique is favorable to fabricating hierarchical 3D polymer nonlinear structures for optoelectronic applications with flexible structural design.  相似文献   
8.
Salmonella typhi was isolated from 369 and Salmonella paratyphi A was isolated from 6 of 515 Vietnamese patients with suspected enteric fever. Compared with conventional broth culture of blood, direct plating of the buffy coat had a diagnostic sensitivity of 99.5% (95% confidence interval [CI], 97.1 to 100%). Blood bacterial counts were estimated by the pour plate method. The median S. typhi count in blood was 1 CFU/ml (range, <0.3 to 387 CFU/ml), of which a mean of 63% (95% CI, 58 to 67%) were intracellular. The mean number of bacteria per infected leukocyte was 1.3 (interquartile range [IQR], 0.7 to 2.4) CFU/cell (n = 81). Children (< 15 years old; n = 115) had higher median blood bacterial counts than adults (n = 262): 1.5 (range, <0.3 to 387) versus 0.6 (range, <0.3 to 17.7) CFU/ml (P = 0.008), and patients who excreted S. typhi in feces had higher bacteremias than those who did not: a median of 3 (range, <0.3 to 32) versus 1 (range, <0.3 to 68) CFU/ml (P = 0.02). Blood bacterial counts declined with increasing duration of illness (P = 0.002) and were higher in infections caused by multidrug-resistant S. typhi (1.3 [range, <0.3 to 387] CFU/ml; n = 313) than in infections caused by antibiotic-sensitive S. typhi (0.5 [range, <0.3 to 32] CFU/ml; n = 62) (P = 0.006). In a multivariate analysis this proved to be an independent association, suggesting a relationship between antibiotic resistance and virulence in S. typhi.  相似文献   
9.
Six bacteriocinlike peptides (plantaricin A [PlnA], PlnE, PlnF, PlnJ, PlnK, and PlnN) produced by Lactobacillus plantarum C11 were detected by amino acid sequencing and mass spectrometry. Since purification to homogeneity was problematic, all six peptides were obtained by solid-phase peptide synthesis and were tested for bacteriocin activity. It was found that L. plantarum C11 produces two two-peptide bacteriocins (PlnEF and PlnJK); a strain-specific antagonistic activity was detected at nanomolar concentrations when PlnE and PlnF were combined and when PlnJ and PlnK were combined. Complementary peptides were at least 10(3) times more active when they were combined than when they were present individually, and optimal activity was obtained when the complementary peptides were present in approximately equal amounts. The interaction between complementary peptides was specific, since neither PlnE nor PlnF could complement PlnJ or PlnK, and none of these peptides could complement the peptides constituting the two-peptide bacteriocin lactococcin G. Interestingly, PlnA, which acts as an extracellular signal (pheromone) that triggers bacteriocin production, also possessed a strain-specific antagonistic activity. No bacteriocin activity could be detected for PlnN.  相似文献   
10.
The use of robots in rehabilitation has become an issue of increasing importance because of the requirement of functional recovery therapy for limbs. A novel pneumatic artificial muscle (PAM) actuator — which has achieved increased popularity for providing safety and mobility assistance to humans performing tasks, as well as providing another advantages such as high strength and power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available, cheap power source, and so on — has been considered during the recent decades for use in a therapy robot, which in particular requires a high level of safety. However, some limitations still exist, such as air compressibility and the lack of damping ability of the actuator to bring the dynamic delay of the pressure response and cause the oscillatory motion. In addition, to aid rehabilitation more efficiently, the robot should adjust its impedance parameters according to the physical condition of the patient For this purpose, the manipulator join is equipped with a Magneto-Rheological Brake (MRB). A new phase plane switching control method using MRB is proposed for tracking sinusoidal waveforms. The effectiveness of the proposed algorithm is demonstrated through an experiment using a fabricated two-axis PAM manipulator. The experiment proves that the stability of the manipulator could be greatly improved using a high gain control without regard to the change of the frequencies of the reference input and the external load condition, and without decreasing the response speed or lowering the stiffness of PAM manipulator.  相似文献   
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