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121.
The NoSQ microarchitecture performs store-load communication without a store queue and without executing stores in the out-of-order engine. It uses speculative memory bypassing for all in-flight store-load communication, enabled by a 99.8 percent accurate store-load communication predictor. The result is a simple, fast core data path containing no dedicated store-load forwarding structures 相似文献
122.
A mechanistic model for 5-axis surface machining with a toroidal-end mill is presented in this work. A graphical representation of the tool movements is used to determine the in-process chip geometry and tool edge contact length using an adaptive and local depth buffer. The graphical representation of the tool movements is generated using either tooth swept sectors that model the tool’s cutting teeth as they rotate or the swept surface of the tool as it moves along the tool path. The mechanistic model was verified with two cutting experiments: The first cutting test showed that the data agrees with the simulation results within 7% of the peak-to-peak forces. The second cutting test modelled a more complex stock surface and tool path. The simulation results were within 10% of the measured peak-to-peak cutting torque. 相似文献
123.
Effects of DC Current on the Mechanical Behavior of AlMg1SiCu 总被引:1,自引:0,他引:1
Joseph S. Andrawes Thomas J. Kronenberger Timothy A. Perkins John T. Roth Russell L. Warley 《Materials and Manufacturing Processes》2007,22(1):91-101
The effect of an electron wind on the mechanical properties of aluminum is investigated with the ultimate goal of establishing a technique by which the mechanical energy associated with the deformation of a material can be reduced without requiring a significant increase in the material's temperature. In the study presented herein, the effect that the electrical flow has on the mechanical properties of aluminum is examined through tensile testing. However, as electricity is passed through the material, some incidental resistive heating occurs. Therefore, in order to isolate the effect of the electrical flow from that resulting from resistive heat, the effect of transient temperatures on the stress-strain behavior of aluminum is also considered, with, and without, the presence of the electrical flow. In addition, variation in the electrical effect, with respect to the aluminum's temper and electrical pre-treating, is investigated. The experimental results indicate that the electrical current has the potential to substantially reduce deformation energies without causing significant increases in the workpiece temperature. The data also indicates that this effect exists regardless of the temper on the material. Finally, the study found that electrically pre-treating the aluminum produced results similar to that of an annealing process (i.e., the energies were significantly reduced). 相似文献
124.
Taylor Steven; Zvolensky Michael J.; Cox Brian J.; Deacon Brett; Heimberg Richard G.; Ledley Deborah Roth; Abramowitz Jonathan S.; Holaway Robert M.; Sandin Bonifacio; Stewart Sherry H.; Coles Meredith; Eng Winnie; Daly Erin S.; Arrindell Willem A.; Bouvard Martine; Cardenas Samuel Jurado 《Canadian Metallurgical Quarterly》2007,19(2):176
Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n = 2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n = 4,494) and a clinical sample from the United States and Canada (n = 390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
W. H. Binder L. Petraru T. Roth P. W. Groh V. Pálfi S. Keki B. Ivan 《Advanced functional materials》2007,17(8):1317-1326
Supramolecular gels consisting of trivalent polyisobutylene and bivalent poly(ethylene oxide) are generated. Strong hydrogen bonding interactions, affixed to the end‐group moieties of the respective polymers (binding constant Kassn = 105 M –1), serve as molecular glue, leading to the formation of weak gels. Two different gels were prepared: one, with a short telechelic poly(ethylene glycol) (PEG) segment (gel A), and one with a longer PEG segment (number‐average molecular weight Mn = 2000 g mol–1) (gel B). Both gels show a significant increase in viscosity upon mixing of the two polymeric components, with a lag time of several minutes, indicative of nucleation mechanisms as the formation principle. However, only gel A displays classical gel‐like behavior, with a loss modulus G′ larger than the storage modulus G″ after formation. Both gels display microphase‐separated behavior with a spacing between 4–5 nm as probed via small‐angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM) measurements. The incorporation of magnetic nanoparticles (Fe2O3; radius r = 3.5 nm) is successfully achieved, generating new magnetic gels with strongly thermoresponsive properties, displaying a strong temperature‐dependent release profile of included dye molecules. Magnetic measurements indicate a superparamagnetic behavior of the incorporated nanoparticles, prospecting the application as magneto‐sensitive delivery gels for pharmaceutical purposes. 相似文献
126.
Yu. Plevachuk S. Mudry V. Sklyarchuk A. Yakymovych U. E. Klotz M. Roth 《Journal of Materials Science》2007,42(20):8618-8621
Viscosity and electrical conductivity of liquid Sn–Ti and Sn–Zr alloys on the Sn-rich side were investigated in a wide temperature
range above the melting temperature. It was shown that admixtures of Ti and Zr considerably increased the viscosity of liquid
Sn. The electrical conductivity of the melts decreased with an increase of the Ti and Zr content. The conductivity results
are interpreted in the context of the s–d hybridization model. 相似文献
127.
Armando Almendarez Camarillo Stephan Volkher Roth Peter Bösecke Stefan Buchner Klaus Krenn Rainer Gehrke Norbert Stribeck 《Journal of Materials Science》2007,42(15):6212-6221
Commercial skived film from ultra-high molecular-weight polyethylene (UHMWPE) with considerable uniaxial orientation of lamellae
is studied by ultra-small-angle X-ray scattering (USAXS) and wide-angle X-ray scattering (WAXS) during melting and crystallization
in order to identify its mechanisms of crystallization. For the analysis of the nanostructure two-dimensional USAXS patterns
are analyzed by means of the multidimensional chord distribution function (CDF) method. WAXS shows that crystallization is
always isotropic and fast. WAXS reflections are observed before—under certain processing conditions—the SAXS pattern becomes
anisotropic. Thus crystallization is decoupled from a slower process of oriented nanostructure formation (nanoforming). If
nanoforming is performed isothermally at 105 °C, the evolving nanodomain layers obtain some preferential orientation, as long
as the orientation of the melt has not previously been erased by melt-annealing at temperatures of 140 °C or above. Crystallization
at temperatures ≥110 °C followed by quenching leads to isotropic nanostructure. Although crystallization is always observed
early in the WAXS patterns, the USAXS patterns exhibit only weak discrete scattering during isothermal treatment at temperatures
of 110 °C and higher. At 105 °C anisotropic isothermal nanoforming starts after 1.5 min. The melting of the original material
resembles an inverted random car-parking mechanism. Only next-neighbor correlations are observed among the crystalline layers.
The average nanodomain layer thickness is only slightly increasing (26–30 nm), whereas the long period increase is strong
(from 60 nm to 140 nm). 相似文献
128.
Spawning habits of fall Chinook salmon in the Hanford Reach of the Columbia River have been documented with annual aerial surveys since 1948. We developed a series of models analysing these data, exploring the influence of environmental factors on the timing of redd construction. These models included a logistic regression and a dynamic modelling approach, with combinations of day of year (as a surrogate for environmental cues such as day length), water temperature and discharge as potential explanatory factors. Results of these analyses indicate that day of year was the strongest predictor of the timing of redd construction, but with significant modifying effects of water temperature and discharge. The dynamic modelling approach provides substantial advantages over a traditional logistic regression, including (1) the ability to treat data collected at non‐synchronous time intervals in a consistent fashion and (2) the ability to easily implement complex functions (e.g., threshold responses) relating behaviour to environmental cues. Evaluation of the series as a whole indicates that the median date of redd construction has increased over time, from approximately day 299 in 1950 to day 307 in 2010, as has the temperature on Oct 1 (16.3 °C–18.1 °C). The degree to which these changes are caused by climate change or dam operations is uncertain, however. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
129.
Matthias Roth Jean-Jacques Lesage Lothar Litz 《International journal of systems science》2013,44(10):1826-1841
In this article a generic method for fault detection and isolation (FDI) in manufacturing systems considered as discrete event systems (DES) is presented. The method uses an identified model of the closed-loop of plant and controller built on the basis of observed fault-free system behaviour. An identification algorithm known from literature is used to determine the fault detection model in form of a non-deterministic automaton. New results of how to parameterise this algorithm are reported. To assess the fault detection capability of an identified automaton, probabilistic measures are proposed. For fault isolation, the concept of residuals adapted for DES is used by defining appropriate set operations representing generic fault symptoms. The method is applied to a case study system. 相似文献
130.
Emilie Beriaux Cozmin Lucau-Danila Eric Auquiere Pierre Defourny 《International journal of remote sensing》2013,34(12):4156-4181
Taking advantage of a large multiyear data set of synthetic aperture radar (SAR) and ground observations collected in Belgium, this research aims at improving the understanding of the SAR signal sensitivity to crop growth by means of water cloud model (WCM) inversion for retrieving maize leaf area index (LAI) from C-band and VV-polarized SAR data. The results show that at intermediate moisture levels, the contributions of both soil and plants to the SAR response are confused as, to the SAR sensor, the vegetation seems to behave as bare soil of about 21% water content. Moreover, as the WCM usually required a calibration every year, this research assessed the robustness of the calibrated WCM by model cross-validation between years for maize. Ten different calibrations and inversions of the WCM were completed based on three years of observations. Two other years of observation serve as independent data sets to calculate the LAI retrieval error. The results demonstrate the capability of transferring the model calibration to independent subsequent crop seasons with an acceptable performance reduction. 相似文献