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381.
TiO2 films were grown by an advanced pulsed laser deposition method (PLD) on ITO substrates to be used as functional electrodes in the manufacturing of solar cells. A pure titanium target (99.99%) was irradiated by a Nd:YAG laser (355 and 532 nm, 5 ns, 35 mJ, 3 J/cm2) in an oxygen atmosphere at different pressures (20-160 mTorr) and at room temperature. After deposition, the films were subjected to an annealing process at 350 °C. The film structure, surface morphology, thickness, roughness, and optical transmission were investigated. Regardless of the wavelength used, the films deposited at room temperature presented only Ti2O and TiO peaks. After thermal treatment, the TiO2 films became strongly crystalline, with a tetragonal structure and in the anatase phase; the threshold temperature value was 250 °C. The deposition rate was in the range of 0.035-0.250 nm/pulse, and the roughness was 135-305 nm. Optical transmission of the films in the visible range was between 40% and 60%. 相似文献
382.
383.
Cornelia Zelinsky-Wibbelt 《Machine Translation》1991,6(3):183-192
This paper is concerned with the conditions under which token reference to individuals comes about on the one hand and type reference to the whole kind of an entity is rendered on the other. We consider how the process of reference comes about with nouns inherently denoting mass concepts and with nouns denoting countable concepts. We exemplify the interpretation of np readings with a rule component which has been implemented in the machine translation system cat2. Out of these np readings those articles are to be generated which are in accordance with the language-specific conventions.I would like to thank Randall Sharp for many discussions particularly about the English examples and for correcting my English. I would also like to thank Nadia Mesli for helping me with the French examples. With respect to my own explanation of the translation from German to French I am indebted to Michael Grabski, whose extensive classification of examples inspired me. Last but not least, thanks are due to the editors Erich Steiner and Valerio Allegranza, who pointed out a number of inconsistencies to me. 相似文献
384.
The paper discusses techniques to emphasize patterns in citation data and to study their dynamics. In this context, the STATIS and the STATIS dual methods are presented. The methods are a generalization of the principal component analysis from a dynamical point of view. STATIS and its dual are applied in order to illustrate the dynamic of "citing-cited patterns" by using citation data of sixteen major journals from the statistics field. 相似文献
385.
386.
Directions of Motion Fields are Hardly Ever Ambiguous 总被引:2,自引:2,他引:0
Brodsky Tomas Fermüller Cornelia Aloimonos Yiannis 《International Journal of Computer Vision》1998,26(1):5-24
International Journal of Computer Vision - If instead of the full motion field, we consider only the direction of the motion field due to a rigid motion, what can we say about the three-dimensional... 相似文献
387.
In analysing action generation in technical system control we differentiate between a purely cognitive stage of pre-actional decision-making and an action-related cognitive-physical stage of action planning and plan execution. This study investigates the impact of interface-induced handling requirements on the action-related processes in the domain of artificial respiration in intensive care. Thirty-two novice and experienced intensive care nurses had to solve three realistic control tasks on two types of respiration unit equipped either with an 'analogue' or with a 'digital' user interface. The quality of the novices' plan execution and—unexpectedly— action planning, too, decreased when working on the 'digital' interface. Interface-induced handling requirements obviously have an important influence on the usability of technical systems not only on a purely cognitive level, but also on the action-related level. 相似文献
388.
Gabriela Chitanu Cornelia Luca Ecaterina Avram A. Airinei I. Petrariu A. Carpov 《应用聚合物科学杂志》1989,37(8):2417-2427
The behavior of various strong basic type II macroporous anion exchangers against the sorption of some organic acid alkaline salts as follows: natrium benzoate, natrium benzenesulfonate, potassium α-naphthylacetate, natrium β-naphthalenesulfonate, and natrium anthraquinone-2-sulfonate was established. The values of the sorption capacities depend on the morphology of anion exchanger network, the type and the size of organic anion, as well as the type of anion exchanger. 相似文献
389.
The 3GPP network specification is currently undergoing major updates toward beyond 3G. The evolved 3GPP network will support interworking with multiple including non-3GPP - radio access networks, and support mobility between them. It will furthermore support personal area networks and moving networks. Generally, 3GPP is moving in the direction of an all-IP network. This article gives an overview of current beyond 3G trends in 3GPP, and particularly introduces a new 3GPP study item on network composition. The concept of network composition was developed by the EU project Ambient Networks. Whereas 3GPP until now assumes static networking relations, network composition addresses a dynamic, generic establishment of control-plane interworking between the heterogeneous network types of today, such as 3GPP core networks, non-3GPP operator networks, heterogeneous access networks, and personal area networks 相似文献
390.
Motion segmentation using occlusions 总被引:4,自引:0,他引:4
Ogale AS Fermüller C Aloimonos Y 《IEEE transactions on pattern analysis and machine intelligence》2005,27(6):988-992
We examine the key role of occlusions in finding independently moving objects instantaneously in a video obtained by a moving camera with a restricted field of view. In this problem, the image motion is caused by the combined effect of camera motion (egomotion), structure (depth), and the independent motion of scene entities. For a camera with a restricted field of view undergoing a small motion between frames, there exists, in general, a set of 3D camera motions compatible with the observed flow field even if only a small amount of noise is present, leading to ambiguous 3D motion estimates. If separable sets of solutions exist, motion-based clustering can detect one category of moving objects. Even if a single inseparable set of solutions is found, we show that occlusion information can be used to find ordinal depth, which is critical in identifying a new class of moving objects. In order to find ordinal depth, occlusions must not only be known, but they must also be filled (grouped) with optical flow from neighboring regions. We present a novel algorithm for filling occlusions and deducing ordinal depth under general circumstances. Finally, we describe another category of moving objects which is detected using cardinal comparisons between structure from motion and structure estimates from another source (e.g., stereo). 相似文献