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991.
For the Visible Korean Human (VKH), a male cadaver was serially ground off to acquire the serially sectioned images (SSIs) of a whole human body. Thereafter, more than 700 structures in the SSIs were outlined to produce detailed segmented images; the SSIs and segmented images were volume- and surface-reconstructed to create three-dimensional models. For outlining and reconstruction, popular software (Photoshop, MRIcro, Maya, AutoCAD, 3ds max, and Rhino) was mainly used; the technique can be reproduced by other investigators for creating their own images. For refining the segmentation and volume reconstruction, the VOXEL-MAN system was used. The continuously upgraded technique was applied to a female cadaver's pelvis to produce the SSIs with 0.1mm sized intervals and 0.1mm x 0.1mm sized pixels. The VKH data, distributed worldwide, encouraged researchers to develop virtual dissection, virtual endoscopy, and virtual lumbar puncture contributing to medical education and clinical practice. In the future, a virtual image library including all the Visible Human Project data, Chinese Visible Human data, and VKH data will hopefully be established where users will be able to download one of the data sets for medical applications.  相似文献   
992.
Windows 2000操作系统下,通过Miniport Driver可以实现软阵列的功能。本文探讨了在这种软阵列中缓存的设计与实现,尤其是在缓存替换算法和通道并行性方面作了比较深入的研究。经在Takram公司的DC-200 EIDE扩展卡上进行测试,缓存的设计使小块I/O请求的性能得到明显改善。  相似文献   
993.
在产品概念设计过程中,明确设计任务,应用数字孪生技术,可以更好地处理大量用户数据、监测功能运行和分析目标产品,促进设计方案的产生。首先,以设计任务为切入点,引入用户因素,集成任务分析法和情景分解法来分解设计任务,构建任务域任务流模型;其次,利用模糊综合评价法量化设计任务,明确设计任务,并对设计任务进行进一步分解,构建物理域实体任务情景模型;基于任务流的走向分析交互通道与虚拟域数据类型,构建虚拟域任务情景模型,完成基于设计任务的数字孪生模型的构建。最后,将这一方法应用于智能分类垃圾桶数字孪生模型的构建,拓展了数字孪生在概念设计中的应用。在产品概念设计阶段将用户因素融入设计任务中,可提高产品的设计质量。  相似文献   
994.
Polypyrrole–poly(?-caprolactone) (PPy–PCL) blends were prepared through an in situ deposition technique wherein different amounts of poly(?-caprolactone) were added during the polymerization of pyrrole. Ammonium persulfate was used as an oxidant in the polymerization of polypyrrole (PPy). Compared with pure PPy, the blends showed higher solubility in many organic solvents. The composition and structural characteristics of PPy–PCL were determined by Fourier transform infrared, ultraviolet–visible, and X-ray photoelectron spectroscopic methods. Scanning electron and transmission electron microscopic methods were performed to observe the morphology of the PPy–PCL blends. The temperature-dependent conductivity of the PPy–PCL blends was measured at 300–500 K. The conductivity increased with increasing PCL concentration in the blends, which can be explained by the increased mobility of charge carriers at high PCL concentrations. Based on the temperature dependence of the electrical conductivity, hopping may be the conduction mechanism involved in the PPy–PCL blending process.  相似文献   
995.
从我院找水实践出发,由水──特殊强极性分子的激发极化效应中探索激电找水机制、方法及注意事项,不同大极距联剖与温纳激电测深配套找水是行之有效的途径,取得很好的社会效益和经济效益.  相似文献   
996.
A delay-locked loop (DLL) architecture capable of incorporating fast locking and low jitter features simultaneously is reported. A test chip was fabricated in a 0.6 μm CMOS process to prove its functionality. The proposed DLL can align the internal clock to the external reference clock within two cycles and maintain its locking state with the aid of feedback operation  相似文献   
997.
Electrical properties of perovskite Li0.055[Agx(K0.5Na0.5)1?x]0.945(Nb1?yTay)O3 (0.00  x  0.04, 0.01  y  0.09) ceramics were investigated based on the structural characteristics. A morphotropic phase boundary (MPB) between orthorhombic and tetragonal phase was detected through the entire range of compositions. With increasing of Ta5+ content, the dielectric constant (?r), piezoelectric coefficient (d33) and electromechanical coupling factor (kp) of Li0.055(K0.5Na0.5)0.945(Nb1?yTay)O3 ceramics were increased up to y = 0.07 and then decreased, while mechanical quality factor (Qm) was increased. However, the ?r, d33, kp and Qm of Li0.055[Agx(K0.5Na0.5)1?x]0.945(Nb0.07Ta0.03)O3 ceramics were not changed remarkably with Ag+ content. The dependence of temperature coefficient of kp (TCkp) on the oxygen octahedral distortion was also discussed by Raman-active vibrations modes.  相似文献   
998.
对百合多糖进行纯化并探究其对肠道菌群失调小鼠的调节作用。以产率、脱色率、多糖含量为指标,比较AB-8、D315、D101、HPD-100四种大孔树脂对百合多糖的纯化效果;实验分为空白组(生理盐水10 mg/kg)、模型组(盐酸林可霉素10 mg/kg)、阳性组(丽珠肠乐10 mg/kg)、百合多糖低、中、高(50、100、200 mg/kg)剂量组;以脂多糖(LPS)、血清炎症因子IL-6、TNF-α及回肠组织SIgA的含量、菌群数量为指标,评价纯化后的百合多糖对肠道菌群失调小鼠的调节作用。结果表明:D315大孔树脂纯化效果最佳,纯化后百合多糖的产率、脱色率、糖含量分别为40.82%±1.28%、35.11%±1.12%、82.56%±1.18%;药理实验结果表明:百合多糖高剂量组(200 mg/kg)效果最佳。与模型组相比,高剂量组小鼠LPS、血清炎症因子IL-6、TNF-α的含量极显著降低(P<0.01),回肠组织SIgA含量极显著增加(P<0.01),肠杆菌、肠球菌的数量显著降低(P<0.05),乳酸杆菌、双歧杆菌的数量显著增加(P<0.05)。说明百合多糖对小鼠肠道菌群紊乱具有调节作用。  相似文献   
999.
虚拟仪器是计算机和仪器技术深层次结合的产物,它将计算机硬件资源、仪器与测控系统硬件资源和虚拟仪器软件资源有效结合起来。文章介绍了基于LabJack U12数据采集器和LabVIEW图形化编程语言组成虚拟仪器测试系统的硬件和软件以及仪器的功能特点,实现了数据采集、测试的控制与实时显示、数据存储与分析等功能,提高了测试的精度。该虚拟仪器灵活性好,能够根据需要移植应用到其它的测试场合。  相似文献   
1000.
Stranded wire is the most important component of familiar mechanical equipment such as elevators, cable cars, and cranes. The quality of these products that are used on a daily basis are mainly affected by the tensile strength of stranded wire. In order to attain the purpose of economical design and a long life span of stranded wire, a less relaxation property of strand type is suitable for manufactured tools. Thus, the manufacturing industries of stranded wire need to reach the goals of high tensile strength and low relaxation. To ensure the required quality of stranded wire, the strand pull test and the long period relaxation test are two important quality assurance tests. There are three specific items of the tensile strength test that belong to the larger-the-better quality type. The quality type of the smaller-the-better is for the long period relaxation test. However, many existing methods are able to measure process capability for the product with a single quality characteristic although it cannot be applied to most products with multiple properties. Thus, the indices of Cpu and Cpl, for the larger-the-better and the smaller-the-better quality type respectively proposed by Kane [5], are quoted and combined to propose a new index to evaluate the quality of multiple characteristics of stranded wire in this article. The principle of statistics is then used to derive the one-to-one mathematical relationship of this new index and ratio of satisfactory production process. Finally, the procedure and criteria to evaluate the quality of stranded wire is proposed. This integrated multi-quality property capability analysis model can be used to evaluate the multi-process capabilities and provide continuous improvements on the manufacturing process of stranded wire.  相似文献   
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