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991.
Services in electronic telecommunication markets: a framework for planning the virtualization of processes 总被引:1,自引:0,他引:1
The potential of electronic markets in enabling innovative product bundles through flexible and sustainable partnerships is not yet fully exploited in the telecommunication industry. One reason is that bundling requires seamless de-assembling and re-assembling of business processes, whilst processes in telecommunication companies are often product-dependent and hard to virtualize. We propose a framework for the planning of the virtualization of processes, intended to assist the decision maker in prioritizing the processes to be virtualized: (a) we transfer the virtualization pre-requisites stated by the Process Virtualization Theory in the context of customer-oriented processes in the telecommunication industry and assess their importance in this context, (b) we derive IT-oriented requirements for the removal of virtualization barriers and highlight their demand on changes at different levels of the organization. We present a first evaluation of our approach in a case study and report on lessons learned and further steps to be performed. 相似文献
992.
Axel Arnault François Mathieu-Potvin Louis Gosselin 《International Journal of Thermal Sciences》2010,49(11):2148-2156
The thermal inertia of building internal components may be used to shift the irradiation (solar) heat load, which could result in substantial energy saving. In this paper, a numerical model was implemented to determine the thermal performance of internal surfaces including Phase Change Materials (PCM). The model was exploited to compare a typical concrete floor with a floor with PCM. Thermal performance was defined by three different objective functions, each pinpointing different thermal characteristics of the heat load. First, parametric studies were performed to understand the influence of the thickness of a typical concrete floor. Then, the optimization of the melting temperature, thickness and position of a PCM layer included in a floor was performed. These analyses used either simplified or real weather conditions (for Québec City). Results showed that the thickness of the concrete floor could be optimized based on the three criteria retained. Also, the floor performance may be enhanced by the inclusion of a PCM layer. It was shown that the gain of performance brought by the internal surfaces thermal mass strongly depends on the weather conditions considered. This paper provides a fundamental understanding of PCM influence on internal surfaces. 相似文献
993.
994.
Harald Gabasch Axel Knop-Gericke Robert Schlögl Werner Unterberger Konrad Hayek Bernhard Klötzer 《Catalysis Letters》2007,119(3-4):191-198
The catalytic oxidation of ethene was studied on Pd(111) in the 10−7–10−6 mbar pressure range by a molecular beam TPR hysteresis experiment between 400 K and 1,000 K. Two important effects were identified:
the reaction-blocking effect of a dense chemisorbed adlayer of oxygen and the promotional effect of dissolved carbon segregating
back to the surface and efficiently reducing the adsorbed oxygen. A strong dependence of the catalytic activity on the oxygen
partial pressure is explained by the inhibiting effect of oxygen adsorption; high oxygen pressures in fact extinguish the
reaction. The presence of oxygen-free metal surface area, where ethene can dissociate, is necessary for high activity. During
heating the highest activity is observed at T ∼ 620 K, where a combination of oxygen clean-off by carbon segregating back to the surface is combined with a high ethene
adsorption rate, thus forming additional reaction sites and additional reaction products. During heating this carbon-induced clean-off of O(ad) is very efficient because the dissolved
C atoms rather accumulate in the surface-near region and largely segregate back to the surface at T > 600 K. In contrast, during cooling from higher temperatures a high surface-near carbon bulk concentration does not build
up because the bulk mobility of C atoms is also high and the faster diffusion of C into deeper layers counteracts carbon enrichment
in the surface-near metal bulk. This effect favours a higher oxygen surface coverage and a stronger deactivation during cooling.
If the carbon loading of the surface-near region was increased by decomposition of clean ethene prior to the reaction experiment,
the promotional effect during the heating cycle was strongly enhanced, but the cooling cycle showed no memory of the C presaturation.
Generally, the observed hysteresis effects stem from an interplay of combined oxygen site blocking and carbon diffusion effects.
Konrad Hayek—deceased. 相似文献
995.
The thermodynamic and mechanical stability of intermetallic phases in the Al3Ti-Zn3Ti pseudobinary alloy system is investigated from first-principles total energy calculations through electronic density-functional
theory within the generalized gradient approximation. Both supercell calculations and sublattice-cluster-expansion methods
are used to demonstrate that the addition of Zn to the Al sublattice of Al3Ti stabilizes the cubic L12 structure relative to the tetragonal D022 and D023 structures. This trend can be understood in terms of a simple rigid-band picture in which the addition of Zn modifies the
effective number of valence electrons that populate bonding and anti-bonding states. The calculated zero-temperature elastic
constants show that the binary end members are mechanically stable in all three ordered phases. These results point to a promising
way to cost effectively achieve the stabilization of L12 precipitates in order to favor the formation of a microstructure associated with desirable mechanical properties.
This article was presented at the Multi-Component Alloy Thermodynamics Symposium sponsored by The Alloy Phase Committee of
the joint EMPMD/SMD of The Minerals, Metals, and Materials Society (TMS), held in San Antonio, TX, March 12-16, 2006, to honor
the 2006 William Hume-Rothery Award recipient, Professor W. Alan Oates of the University of Salford, UK. The symposium was
organized by Y. Austin Chang of the University of Wisconsin, Madison, WI, Patrice Turchi of the Lawrence Livermore National
Laboratory, Livermore, CA, and Rainer Schmid-Fetzer of the Technische Universitat Clausthal, Clauthal-Zellerfeld, Germany. 相似文献
996.
Buchner Axel; Steffens Melanie C.; Berry Dianne C. 《Canadian Metallurgical Quarterly》2000,26(5):1215
M. R. Banaji and A. G. Greenwald (1995) demonstrated a gender bias in fame judgments—that is, an increase in judged fame due to prior processing that was larger for male than for female names. They suggested that participants shift criteria between judging men and women, using the more liberal criterion for judging men. This "criterion-shift" account appeared problematic for a number of reasons. In this article, 3 experiments are reported that were designed to evaluate the criterion-shift account of the gender bias in the false-fame effect against a distribution-shift account. The results were consistent with the criterion-shift account, and they helped to define more precisely the situations in which people may be ready to shift their response criterion on an item-by-item basis. In addition, the results were incompatible with an interpretation of the criterion shift as an artifact of the experimental situation in the experiments reported by M. R. Banaji and A. G. Greenwald. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
Keitaro Kondo Isao Murata Axel Klix Klaus Seidel Hartwig Freiesleben 《Fusion Engineering and Design》2009,84(7-11):1076-1080
In an irradiation experiment using a LiAl/Pb assembly, we found out that the neutron flux inside the assembly calculated with JENDL-3.3 underestimates an experimental value in the 10–16 MeV region by around 30% and that in the 0.5–5 MeV region by around 15%, while the calculated flux with JEFF-3.1 overestimates the measurement in the 5–10 MeV region by around 20%. In order to reveal a reason of the discrepancy, problems of the nuclear data libraries for lead were investigated. As a result, the following problems of the evaluated libraries were pointed out: the cross-sections of the (n,2n) reaction in JENDL-3.3 for lead isotopes are too large and cause a significant underestimation of the neutron flux above 10 MeV, which appeared in the analysis of the above experiment. Inelastic scattering data for 208Pb in JENDL-3.3 reproduce previous experimental double-differential cross-section data most well. However, those for the other lead isotopes have some problems and cause a large underestimation of the neutron flux from 0.5 to 5 MeV. The reason of the overestimation in the energy region of 5–10 MeV with JEFF-3.1 is still unclear. 相似文献
999.
The present report presents results obtained from an interlaboratory test. 28 participants, mainly from industry and research institutes, measured glass transition temperatures (Tg) by differential scanning calorimetry (DSC) on four different polymers. The materials used were poly(methyl methacrylate) (PMMA), polycarbonate (PC), polysulfone (PSU) and amorphous polyamide (PA 6I/6T). The measured data were collected by EMPA and were evaluated using a robust statistical method. Repeatability and reproducibility data were of special interest. The repeatability limit (r) of glass transition temperatures measured according to DIN 53765 was found in the region of 1–2°C, and the reproducibility limit (R) was around 3–4°C. In addition to the DIN standard, the set of interlaboratory test data was evaluated and considered according to some different approaches and was correlated with data from other EMPA interlaboratory tests performed previously. It was shown that the investigated statistical parameter was always in a similar dimension. The data of the PA sample were found to be an exception. Due to the hygroscopic character of polyamide, the r and R values increase sharply, to an almost three times higher reproducibility limit. Overall, the evaluated data can be used to estimate the results of own and external Tg measurements and their compatibility. The report should therefore support daily work in analytical laboratories where glass transition temperatures are measured by DSC. 相似文献
1000.