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981.
虚拟场景漫游系统是虚拟现实技术的具体应用.以大庆师范学院主校区为例,主要介绍了校园漫游系统的前期准备和中期三维模型创建过程,重点阐述了用3ds Max对校园内建筑模型的构造、模型的优化、场景合并等制作过程、制作时遇到的问题以及问题的解决方法.  相似文献   
982.
遥感数据同化技术在动力模型框架内,使用数据同化算法对动力模型输出的定量(物理、化学量)数据与观测数据进行一致性处理与结果误差分析。将多源遥感数据同化到动力模型预测与参数估计中,可帮助改善地表、大气和海洋变化的分析和预测精度。以国家发改委"十二五"建设的国家航空遥感系统项目为依托,针对航空遥感系统10种传感器设计开发数据同化系统。因无法找到适用于该系统的3DVAR和EnKF算法程序,必须自主开发核心算法程序。介绍了研究开发的航空遥感数据同化算法集成计算与可视化系统及其核心算法的关键技术流程。实验结果证实,该系统可以有效地对航空遥感数据进行同化。  相似文献   
983.
结合我公司的实际案例,分析公司信息化建设过程中存在的问题,并提出了公司未来信息化建设的发展方向和对策。  相似文献   
984.
介绍了近几年来国内外发展起来的石油脱酸技术方法,其中重点介绍了碱洗脱酸技术、氨醇脱酸技术、加氢脱酸技术、热分解脱酸技术、溶剂抽提脱酸技术等除去油中环烷酸技术,分析对比了各种脱酸技术的优劣,并阐述了脱酸分离技术在国内外的研究现状及发展趋势。  相似文献   
985.
A new group-contribution method involving specific gravity as a parameter is proposed for predicting criticaltemperature.Being appliable to all kinds of organic compounds,it gives an average percent deviation of 0.88%for 93 compounds and is particularly useful to those substances for which the normal boiling points are stillunknown.  相似文献   
986.
"Zero-loop" of the molecular potential transformer of submitochondrial particles (SMP) is separated from the remaining electron transfer chain by rotenone, and its e.m.f. ET=0,003+RT/2F in [NADP X H] [NAD+]/[NADP+] [NAD X H] volts is used in the compensative method of measurement of the potential difference across the SMP membrane (delta USMP). The phospholipid membrane, measuring the concentration of the penetrating anions in the solution contained SMP, is used as "zero-indicators". This concentration drops monotonically with increase in delta USMP. Delta USMP is equal to ET when the addition of substrates of transhydrogenase reaction with definite ET does not change the potential across phospholipid membrane.  相似文献   
987.
In experiments carried out on Wistar rats ultrastructrual charges of hepatocytes were studied during long-term carcinogenesis due to N-Nitrosomorpholine administered as a 20 mg% solution in drinking water. Carcinoma usually developed after the 20th week of the experiment. The development of the tumour was preceded by early dystrophic changes and, later, by a precancerous posttoxic "glycogenosis". The structural alterations as observed during the precancerous stage were rather noncharacteristic so that they did not permit to disclose the exact point of neoplastic change of the hepatocytes. Nevertheless, the model of carcinogenesis as demonstrated here appears to be a rather standard one and seems to be suitable for studying oncological problems of general character.  相似文献   
988.
Traumatic dislocations and subluxations of the upper extremity in children have been surveyed. The elbow joint is most commonly dislocated and is dislocated more frequently in children than in adults. Severe neurovascular injury may be associated with dislocation of this joint. The most common subluxation is that of the radial head, secondary to a "pulled elbow." Otherwise dislocations and subluxations of the upper extremity are uncommon in children, apparently because of the relative weakness of the epiphyseal plate. Most of these injuries are the result of predictable indirect forces. Principles of reduction and immobilization are based on the unique anatomic structure of the joint involved and the known anatomic disruption resulting from the trauma.  相似文献   
989.
Two hundred open heart cases anaesthetized with a combination of diazepam-ketamine using "Micro-Mini" drip administration technique were presented. The results were eminently desirable, and in the opinion of the authors are a notable improvement over other methods for all types of cardiovascular surgery including most advanced heart diseases. The advantages of this anaesthetic method for cardiovascular surgery are as follows: 1. Effects on cardiovascular system are minimal.--2. Respiratory depression is negligible.--3. There is no increase in salivation or muscle tone.--4. Induction and maintenance of anaesthesia are simple and smooth.--5. Anaesthesia can be maintained, using a high concentration of oxygen alone, by a slight increase in rate of ketamine administration whenever necessary.--6. Post-anaesthetic psychotomimetic effects are negligible.--7. Nearly 100% of patients have excellent amnesia.--8. It has a wide margin of safety.--9. This technique has proved highly acceptable to patients and surgeons. We feel ketamine should be used in small dosages continuously administered with either "Micro-Mini" drip infusion or infusion pump. Ketamine given in this fashion should be regarded as an analgesic.  相似文献   
990.
Two hundred open-heart cases were anaesthetized with a diazepam-ketamine combination. The results were excellent. A "Micro-Mini" drip technique insured low, even, but adequate dose levels of ketamine and less drug was used. Induction and maintenance are simple and smooth. Effects on the cardiovascular system and respiratory system are minimal. The margin of safety is wide and 100% oxygen can be used whenever needed.  相似文献   
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