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61.
用手工进行报表数据处理,已经越来越不适应现代社会的要求,本文提出了一种结合Delphi组件FlBook,在电子报表中自定义公式进行数据处理的实现方法,给出了采用面向对象编程的表达式解释实现技术。  相似文献   
62.
通过模拟计算与分析,提出了种无梁板支承条件的调整方式,并对调整后结构的内力影响问题进行讨论。  相似文献   
63.
Two sustained-release (SR) lithium carbonate (Li) matrix tablets, which use a hydrophilic (HP) matrix of hydroxypropylmethylcellulose (Methocel 4K MP) and a lipid (L) matrix of hydrogenated castor oil (Cutina HR) as sustaining agents, have been studied. In vitro performance through dissolution tests in different media was established. The L and HP formulations were affected by the composition of the dissolution media, and liberation was complete in 8 hr using a variable-pH medium that simulates the gastrointestinal (Gl) pH. Liberation was better described by the diffusional model of the square root of time for the L matrix and by zero-order kinetics for the HP matrix. Absolute bioavailability (BA) and food-induced changes on BA of both formulations were studied. The in vivo study design was a 4 x 4 Latin square involving 12 subjects who received two tablets of a 300-mg dose of SR formulations while fasting or with a standardized normal, high-fat, or high-fat/high-protein meal. The results for both formulations showed no differences in the disposition parameters and mean residence time when the tablets were administered with any type of diet. Changes in rate of absorption were found when both types of tablets were administered with any class of diet. The analysis of the ratio Cmax/AUC (area under the curve) evidenced that changes in Cmax were attributable to a higher rate of absorption for the HP matrix and to a higher amount absorbed for the L matrix. In the last, high-fat and high-fat/high-protein diets produced higher AUCs than under fasting condition. The SR Li tablets formulated with hydrogenated castor oil were affected more by high-fat food, probably because of the increase of pancreatic and biliary secretions promoted by the meal, which would affect the matrix itself. The HP matrix was also affected, but to a lesser extent. The magnitude of the change in Cmax observed with this matrix probably is not important from a clinical point of view. Absolute BA was very low for the lipid matrix; in addition, since it is more seriously affected by food, probably it is not a good choice for a drug such as lithium. The in vivo behavior of the HP matrix makes it advisable to invest in efforts to achieve increased BA. Comparing in vitro and in vivo results, the focus should be achieving sustained, but complete, in vitro liberation in not more than 3 hr, with simulation of the transit time through the stomach and small bowel since lithium ion is only absorbed to this point.  相似文献   
64.
玻璃纤维增强MC尼龙复合材料的力学性能   总被引:7,自引:0,他引:7  
考察了玻璃纤维增强MC尼龙(GFRMCN)中玻璃纤维的表面处理及加入量对力学性能的影响。并用SEM对GFRMCN材料界面及其对力学性能的影响进行了研究。结果表明:使用KH550作偶联剂对GFRMCN复合材料是很有效的。当玻纤加入40%时,拉伸强度比基体提高32.2%,拉伸弹性模量提高了152%,弯曲强度提高74.3%,弯曲弹性模量提高了117%,而缺口冲击韧性提高了162%。根据材料的制备工艺特点  相似文献   
65.
夹芯板弯曲屈曲分析的有限条-棱方法   总被引:1,自引:1,他引:0  
王海忠  何保康 《工业建筑》2002,32(11):51-52,60
用有限条 -棱方法对冷弯薄壁型钢压型表面泡沫夹芯板进行了弯曲屈曲分析 ,得到了夹芯板受压面层屈曲时的临界应力、屈曲荷载及屈曲半波长 ,并与试验结果进行对比 ,理论值与试验值吻合较好  相似文献   
66.
67.
坝体建筑物的老化及其对坝体安全的影响   总被引:2,自引:0,他引:2  
水工坝体的老化按部位可分为坝体混凝土老化和坝基岩石老化.分析了混凝土和岩石的主要力学性能随时间的变化规律,并用简单的工程实例对老化期中的坝体结构进行坝体损伤和坝基屈服计算,进一步阐述了水工坝体建筑物老化对坝体结构安全的影响.  相似文献   
68.
开发一种通用化的处理程序,它可以自动从指定的Web页面中提取地震事件公报,采用XSLT将数据转换为指定格式的XML文档,存入地震信息数据库,实现了Web数据的清理与集成.  相似文献   
69.
In this paper, we propose a novel approach to integrate virtual pedestrians into a scene of real pedestrian groups with behavior consistency, and this is achieved by dynamic path planning of virtual pedestrians. Rather than accounting for the local collision avoidance only, our approach is capable of finding an optimized path for each virtual pedestrian on his way based on the current global distribution of the real groups in the scene. The big challenge is due to the information of both position and velocity of real pedestrians in the video being unavailable; also the distribution of the groups in the scene may vary dynamically. We therefore need to detect and track real pedestrians on each frame of the video to acquire their distribution and motion information. We save this information by an efficient data structure, called environment grid. During the way of a virtual pedestrian, the respective agent frequently emits the detection rays through the environment cells to find the situation of the real pedestrians ahead of him and adjust the original path if necessary. Virtual pedestrians are merged into the video finally with the occlusion between virtual characters and the real pedestrians correctly presented. Experiment results on several scenarios demonstrate the effectiveness of the proposed approach.  相似文献   
70.
Several recent methods have been proposed to obtain significant speed-ups in MRI image reconstruction by leveraging the computational power of GPUs. Previously, we implemented a GPU-based image reconstruction technique called the Illinois Massively Parallel Acquisition Toolkit for Image reconstruction with ENhanced Throughput in MRI (IMPATIENT MRI) for reconstructing data collected along arbitrary 3D trajectories. In this paper, we improve IMPATIENT by removing computational bottlenecks by using a gridding approach to accelerate the computation of various data structures needed by the previous routine. Further, we enhance the routine with capabilities for off-resonance correction and multi-sensor parallel imaging reconstruction. Through implementation of optimized gridding into our iterative reconstruction scheme, speed-ups of more than a factor of 200 are provided in the improved GPU implementation compared to the previous accelerated GPU code.  相似文献   
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