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991.
Wechselbeziehungen zwischen Zustandsschaubild und thermodynamischen Eigenschaften von Phasen eines Systems. Berechnung thermodynamischer Daten nach dem Zustandsschaubild und Berechnung von Phasengleichgewichten aus den Zustandsfunktionen. Einfluß der chemischen Bindungsverhältnisse, der Atomradiendifferenz und struktureller Gegebenheiten auf die thermodynamischen Eigenschaften und die Phasengleichgewichte. 相似文献
992.
Bruno Camoin 《电信纪事》1976,31(7-8):239-267
The investigations aimed at the building of a supervisor of the national telephone network require mathematical models of traffic flows (especially when perturbations occur). This paper describes an analytical model of traffic developped at the Centre National d’Etudes des Télécommunications in 1975. It allows quantitative analysis of traffic flows and of their interactions with the different elements of the network. 相似文献
993.
High-quality animation of 2D steady vector fields 总被引:2,自引:0,他引:2
Simulators for dynamic systems are now widely used in various application areas and raise the need for effective and accurate flow visualization techniques. Animation allows us to depict direction, orientation, and velocity of a vector field accurately. We extend a former proposal for a new approach to produce perfectly cyclic and variable-speed animations for 2D steady vector fields [B. Jobard, et al., (1997)] and [C. Chedot, et al., (1998)]. A complete animation of an arbitrary number of frames is encoded in a single image. The animation can be played using the color table animation technique, which is very effective even on low-end workstations. A cyclic set of textures can be produced as well and then encoded in a common animation format or used for texture mapping on 3D objects. As compared to other approaches, the method presented produces smoother animations and is more effective, both in memory requirements to store the animation, and in computation time. 相似文献
994.
Michele Cincera Bruno van Pottelsberghe de la Potterie Veugelers Reinhilde 《Scientometrics》2006,66(3):493-512
Summary International R&D activities have grown significantly over the last two decades. Both the number of actors involved, as well
as the importance of the technological activity carried out abroad, has considerably increased. We aim to quantify the international
generation of knowledge for the case of Belgium, using indicators based on EPO and USPTO patent data (1978-2001). We distinguish
among Belgian applicants, affiliates of foreign firms located in Belgium as well as Belgian based firms with affiliates abroad.
This approach allows to improve existing indicators of internationalisation of technology based on patent data. The results
are consistent with what can be expected for a small open economy as Belgium. A large part of patents with Belgian inventors
are assigned to Belgian affiliates of foreign firms. Hence our more complete indicator of foreign ownership gives a substantially
higher foreign control of Belgian inventors. Relatively more knowledge generated by Belgian inventors flows out of the country
towards foreign owners of technology, than that knowledge generated abroad is owned by Belgian patent applicants. But the
share of foreign inventors to Belgian assigned patents is considerably increasing over time, especially in the subcategory
of Belgian firms with foreign affiliates. 相似文献
995.
Faces are perceived holistically, a phenomenon best illustrated when the processing of a face feature is affected by the other features. Here, the authors tested the hypothesis that the holistic perception of a face mainly relies on its low spatial frequencies. Holistic face perception was tested in two classical paradigms: the whole-part advantage (Experiment 1) and the composite face effect (Experiments 2-4). Holistic effects were equally large or larger for low-pass filtered faces as compared to full-spectrum faces and significantly larger than for high-pass filtered faces. The disproportionate composite effect found for low-pass filtered faces was not observed when holistic perception was disrupted by inversion (Experiment 3). Experiment 4 showed that the composite face effect was enhanced only for low spatial frequencies, but not for intermediate spatial frequencies known be critical for face recognition. These findings indicate that holistic face perception is largely supported by low spatial frequencies. They also suggest that holistic processing precedes the analysis of local features during face perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
996.
RFID malware: Design principles and examples 总被引:1,自引:0,他引:1
This paper explores the concept of malware for Radio Frequency Identification (RFID) systems — including RFID exploits, RFID worms, and RFID viruses. We present RFID malware design principles together with concrete examples; the highlight is a fully illustrated example of a self-replicating RFID virus. The various RFID malware approaches are then analyzed for their effectiveness across a range of target platforms. This paper concludes by warning RFID middleware developers to build appropriate checks into their RFID middleware before it achieves wide-scale deployment in the real world. 相似文献
997.
998.
Water management is a key issue to get satisfactory and stable Polymer exchange membrane fuel cell (PEMFC) performances. The work reported in the present paper focuses on the determination of the operational conditions when using PEMFC stack working with ambient air without extra humidification. The objectives are to reduce as much as possible the auxiliaries consumptions. As far as the reaction air blower is concerned, the specific goal of the present tests is to find the minimum air flow rate to feed the PEMFC stack in order to prevent flooding. Our particular interest concerns the control of a PEMFC stack to power a prototype vehicle for the Shell Eco Marathon race. 相似文献
999.
Isabelle Favier Montserrat Gmez Guillermo Muller M. Rosa Axet Sergio Castilln Carmen Claver Susanna Jansat Bruno Chaudret Karine Philippot 《Advanced Synthesis \u0026amp; Catalysis》2007,349(16):2459-2469
Palladium nanoparticles ( Pd1 – Pd3 ) stabilized by chiral diphosphite ligands ( 1 – 3 ), were synthesized and tested as catalysts for the allylic alkylation reaction, using different substrates (rac‐ I , rac‐ III and rac‐ V ). Carbohydrate ligands ( 1 and 2 ), only differing in the C‐3 configuration, led to a remarkable difference in stability of the corresponding nanoparticles: while Pd1 is a robust catalyst, Pd2 decomposes into molecular species. In addition, the high enantioselective systems, Pd1 and Pd3 , are only active for a substrate containing phenyl groups. Concerning the catalytic behaviour of the corresponding molecular systems, palladium complexes coordinated to ligands 1 or 3 , gave excellent asymmetric inductions, but an analogous catalyst accommodating ligand 2 , was not found selective. 相似文献
1000.
We extend the concept of CONWIP control to a job shop setting, in which multiple products with distinct routings compete for the same set of resources. The problem is to determine the fixed overall WIP level and its allocation to product types (WIP mix) to meet a uniformly high customer service requirement for each product type. We formulate an optimization problem for an open queuing network model in which customer orders pull completed products from the system. Then, assuming heavy demand, we derive a throughput target for each product type in a closed queuing network and provide a simple heuristic to find a minimum total WJP and WIP mix that will achieve an operating throughput close to this target. In numerical examples, the WIP mix suggested by this approach achieves the customer service requirement with a relatively low total WIP 相似文献