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1.
2.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time. 相似文献
3.
钻一口通过主采盐层的水平井与已完成的直井对接,形成连通井(形如“U”字),一口井注水溶解盐/芒硝矿,另一口井采出卤水,这是盐化工业对钻井提出的要求。针对水平对接盐井井身轨迹设计、着陆段、水平段的轨迹控制和连通技术,介绍了水平段侧钻时的钻井液技术。 相似文献
4.
Andreja ?gajnar Gotvajn Jana Zagorc-Kon?an Tatjana Ti?ler 《Canadian Metallurgical Quarterly》2007,133(1):89-94
The preoxidation of a highly polluted waste pharmaceutical fermentation broth using wet air oxidation (WAO) has been studied as a possible method for the effective removal of organics. The applied (pre)treatment method should enhance the biotreatability of the pharmaceutical fermentation broth in terms of reduced initial toxicity and higher biodegradability. Preliminary experiments in the pilot biological treatment plant were successful only at low organic loads, whereas the system collapses at higher ones. The characterization of the fermentation broth was started by common physicochemical analysis, whereas several bioassays were used to determine its impact on biological treatment plants and the environment. Toxicity prior to and after WAO was determined using the acute Vibrio fischeri test, measurement of inhibition of O2 consumption, and the Daphnia magna acute test. Ready biodegradability of the treated and untreated broth has also been assessed. WAO experiments were accomplished in the 2?L batch reactor at different temperatures (240/280°C) and operating pressures. WAO experiments confirmed reduction of the toxicity toward microorganisms, whereas oxidized wastewater was more toxic to daphnids. Biodegradability of the oxidized broth has also been enhanced. Further work has been focused on designing appropriate combination of WAO and biological processes. 相似文献
5.
D. Dietrich ÖVE H. Reiter Th. Sauter H. -J. Schweinzer 《e & i Elektrotechnik und Informationstechnik》1997,114(5):225-230
The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject. 相似文献
6.
M. Muhr ÖVE S. Pack ÖVE H. Haidvogl F. Kreyca 《e & i Elektrotechnik und Informationstechnik》1997,114(11):680-686
Recently appeared defects on high voltage cables have required an urgent evaluation of the impact of lightning strikes necessary. In some cases overvoltages between the copper wire screen of the cable and earth may appear which cause damages of the cablesheath. Field measurements with a classification of the voltage impulses at the copper wire screen have been made to evaluate the number of events. Additionally a numerical model was developed to study the effects of atmospheric discharges on underground cables with emphasis to the influence on the cablesheath. This numeric method was also applied to estimate the effectiveness of different protection arrangements. This contribution presents evaluation methods for overvoltages of cables and a model used firstly for calculating the stress caused by differential voltages and secondly to determinate the influence of protection measures. 相似文献
7.
长25-29井在完井阶段通井过程中发生粘附卡钻事故,在处理卡钻过程中又发生卡套铣筒、井漏、溢流等事故及复杂情况。通过对井下情况的认真分析,采取先堵漏后循环再解卡的处理方案,顺利地解除了该次卡钻事故,大大地减少了经济损失。 相似文献
8.
Cortical bone remodeling rates for rib samples from three archaeological populations and a modern autopsy sample were determined using an algorithm developed by Frost (Frost [1987a] Calcif. Tissue Res. 3:211-237). When plotted against the relative antiquities for population samples, histomorphometric variables; i.e., activation frequency (mu rc), net bone formation (netVf,r,t), and mean annual bone formation rate (Vf,r,t), exhibit a concordant trend of increased cortical bone remodeling activity levels over time. Two intensive foraging populations, Windover and Gibson, are similar for all bone remodeling parameters and have the lowest remodeling activity levels among the samples. The more recent Ledders sample, which is reported to practice agricultural subsistence, is consistently intermediate between these and a modern autopsy sample. Although there appear to be differences in bone formation rates among the populations it is concluded that these differences cannot be attributed to differences in bone remodeling rates among the populations, but rather are reflecting different effective ages of adult compacta for their ribs. These findings suggest that the earlier populations, particularly Windsor and Gibson, appear to have reached skeletal maturity at an older age than observed for modern. 相似文献
9.
面对WTO的挑战 ,企业要真正成为市场竞争的主体 ,必须做大做强 ,走规模化、集团化的道路 ,为此 ,研究和制定企业发展战略非常重要。从企业发展战略委员会、战略研究中心的职责、战略研究工作内涵等方面进行了初步探讨 相似文献
10.
Klaus Fröhlich Öve Gerfried Zeichen 《e & i Elektrotechnik und Informationstechnik》1998,115(4):226-226
Ohne Zusammenfassung 相似文献