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991.
Christopher A. Brown William A. Johnsen Kevin M. Hult 《International Journal of Machine Tools and Manufacture》1998,38(5-6)
The scale-of-interaction is presented as a criterion for establishing functional correlations. It is also used in simulating interactions with rough surfaces. Fractal analysis by the patchwork method is discussed and is used as the basis for evaluating data acquisition systems. The patchwork method is also used as the basis for simulating interactions with the surface. The essence of the simulation is to understand macroscopic, apparently continuous, interactions as the sum of a large number of discrete interactions at some appropriately fine scale. The simulations shown here use topographic data acquired from engineering surfaces. 相似文献
992.
Placement of Substrate Contacts to Minimize Substrate Noise in Mixed-Signal Integrated Circuits 总被引:1,自引:0,他引:1
Radu M. Secareanu Scott Warner Scott Seabridge Cathie Burke Thomas E. Watrobski Christopher Morton William Staub Thomas Tellier Eby G. Friedman 《Analog Integrated Circuits and Signal Processing》2001,28(3):253-264
The placement of substrate contacts in epi and non-epi technologies is analyzed in order to control and reduce the substrate noise amplitude and spreading. The choice of small or large substrate contacts or rings for each of the two major technologies is highlighted. Design guidelines for placing substrate contacts so as to improve the noise immunity of digital circuits in mixed-signal smart-power systems are also presented. 相似文献
993.
Oxidation reactions over a model monolith-supported Pt–Pd/Al2O3 diesel oxidation catalyst were characterized as a function of temperature and position within the catalyst using spatially resolved capillary-inlet mass spectrometry (SpaciMS). The data obtained demonstrate that H2 and CO are oxidized prior to C3H6 and C12H26 and clearly show back-to-front ignition of the reductant species. Significant NO oxidation was observed simultaneous to dodecane light-off, likely related to dodecane partial oxidation products. 相似文献
994.
William A. Spratley 《The Electricity Journal》1998,11(10):40-50
The transition away from regulated, vertically integrated monopolies provides an opportunity to establish photovoltaics as a viable and popular distributed resource. State policymakers can play a critical role in offering customers new solar energy choices. 相似文献
995.
William T. Westfield 《Fire Technology》1971,7(1):69-81
Temperatures created in aircraft jet engines have given rise to concern over hot surface ignition of flammable fluids. For
some time, 500° F has been accepted as the maximum safe surface temperature. Under the specific conditions reported here,
it appears that this figure can be increased significantly.
Note: This paper was originally presented by the author at the National Air Transportation Meeting held in New York City, April
21–24, 1969, and was published by the Society of Automotive Engineers. 相似文献
996.
A paired comparison experiment for gathering expert judgment for an aircraft wiring risk assessment 总被引:1,自引:0,他引:1
Thomas A. Mazzuchi William G. Linzey Armin Bruning 《Reliability Engineering & System Safety》2008,93(5):722-731
Wire failure in aircraft can be attributed to several factors and the assessment of the risk of wire failure is becoming an increasingly important task. This paper will discuss the results of an actual experiment to use the paired-comparison technique for expert judgment to develop a relationship for the probability of wire failure as a function of influencing factors in an aircraft environment. The reasons for using this technique are two-fold. First, the failure probability depends on many variables including wire gauge, vibration, environmental condition, etc. In addition, the wire failure data are sparse and fitting these data to a complex failure function is a nontrivial task that may involve a host of assumptions that may not be provable.We describe a method for using actual failure data and the results from a paired comparison to populate the model parameters. In the approach, paired comparison data from select environments is used to obtain failure rate estimates for the candidate environments. Next, a functional relationship for wire failure as a function of the environments is constructed using a proportional hazards model. A regression model is fit from the failure rate estimates to the environmental variables and is used as an estimate of the failure response surface. This technique is being investigated as a means to generate failure rates for an electrical wiring interconnection system (EWIS) risk assessment software tool currently being developed for the FAA Tech Center. 相似文献
997.
Behfar Kristin J.; Peterson Randall S.; Mannix Elizabeth A.; Trochim William M. K. 《Canadian Metallurgical Quarterly》2008,93(1):170
[Correction Notice: An erratum for this article was reported in Vol 93(2) of Journal of Applied Psychology (see record 2008-02855-019). Figure 2 on p. 184 (Theoretical Contributions section) is missing information about the numbers of teams and statements for the two groups using particularlistic strategies. For the decreasing and consistently low performance/decreasing and consistently low satisfaction group, there were 14 teams and 40 statements; for the decreasing and consistently low performance/increasing and consistently high satisfaction group, there were 11 teams and 46 statements.] This article explores the linkages between strategies for managing different types of conflict and group performance and satisfaction. Results from a qualitative study of 57 autonomous teams suggest that groups that improve or maintain top performance over time share 3 conflict resolution tendencies: (a) focusing on the content of interpersonal interactions rather than delivery style, (b) explicitly discussing reasons behind any decisions reached in accepting and distributing work assignments, and (c) assigning work to members who have the relevant task expertise rather than assigning by other common means such as volunteering, default, or convenience. The authors' results also suggest that teams that are successful over time are likely to be both proactive in anticipating the need for conflict resolution and pluralistic in developing conflict resolution strategies that apply to all group members. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Ivan R. Lawler Jessica Stapley William J. Foley Bart M. Eschler 《Journal of chemical ecology》1999,25(2):401-415
We investigated the hypothesis that feeding deterrence of common ringtail possums (Pseudocheirus peregrinus) and common brushtail possums (Trichosurus vulpecula) by Eucalyptus terpenes (in this case 1,8-cineole) is a result of a conditioned flavor aversion (CFA), due to the association of terpenes with postingestive effects of another group of Eucalyptus toxins, the diformylphloroglucinol compounds (DFPCs). Wild-caught common ringtail and common brushtail possums showed a dose-dependent reduction in food intake when 1,8-cineole was added to the diet. However, after continued exposure over 12 days to increasing amounts of cineole in the diet, both species substantially increased their intakes of cineole relative to control animals. This indicated that the aversion to cineole was a conditioned response rather than a physiological limitation in their ability to detoxify terpenes. Subsequent exposure to a diet including both cineole and jensenone (a simple DFPC also found in Eucalyptus and considered to cause postingestive emesis) in corresponding amounts was able to recondition the dose-dependent aversion. Consequently, animals that had been given jensenone showed an aversion to cineole-rich diets that matched the behavior of animals in the control group. This supported our hypothesis that the effect of terpenes on feeding of these marsupial folivores on Eucalyptus is due to a CFA. Possums can cope with levels of terpenes in the diet that far exceed those occurring naturally. The role of terpenes in marsupial folivore–Eucalyptus interactions appears to be to act as a cue to levels of toxic DFPCs in the leaves, rather than acting as toxins in their own right. 相似文献
999.
1000.
Alicia B. Brune Robert I. Mangham William T. Petuskey 《Journal of Materials Science》2008,43(2):621-634
Hydrogen-based niobates and niobate-titanates were derived from the pyrochlores Pb1.5Nb2O6.5 (PN) and Pb2Nb1.33Ti0.67O6.67 (PNT) by ion exchange in acid baths, affording sub-micron size white powders. The niobium sublattice was left intact, as
shown by X-ray diffraction. A combination of stripping and thermogravimetric analyses gave the effective formulas H2.66Pb0.17Nb2O6.5·0.5H2O (HPN) and H3.88Pb0.06Nb1.33Ti0.67O6.67·0.33H2O (HPNT). The corresponding structural refinements gave good fits to the XRD data. Densities measured by He pycnometry agreed
with densities calculated from XRD analyses and the effective formulas. Thermal stability was assessed by TGA, DSC, and XRD.
With increasing temperature, HPN and HPNT lost weight (H2O), becoming amorphous, and then transforming to crystalline phases, with greatly reduced particle size. HPN was more stable
than HPNT. The electrical conductivities of powder compacts in wet atmospheres were moderate and attributed mainly to proton
conduction; i.e., 10−6 to 10−5 S cm−1 for HPN and 10−7 to 10−6 S cm−1 for HPNT (from room temperature to 230 °C). Experimental results were interpreted in terms of Nb(V) being a stronger electron
acceptor than Ti(IV). 相似文献