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211.
Freehand 3D ultrasound is increasingly being introduced in the clinic for diagnostics and image-assisted interventions. Various algorithms exist for combining 2D images of regular ultrasound probes to 3D volumes, being either voxel-, pixel- or function-based. Previously, the most commonly used input to 3D ultrasound reconstruction has been digitized analog video. However, recent scanners that offer access to digital image frames exist, either as processed or unprocessed data. To our knowledge, no comparison has been performed to determine which data source gives the best reconstruction quality. In the present study we compared both reconstruction algorithms and data sources using novel comparison methods for detecting potential differences in image quality of the reconstructed volumes. The ultrasound scanner used in this study was the Sonix RP from Ultrasonix Medical Corp (Richmond, Canada), a scanner that allow third party access to unprocessed and processed digital data. The ultrasound probe used was the L14-5/38 linear probe. The assessment is based on a number of image criteria: detectability of wire targets, spatial resolution, detectability of small barely visible structures, subjective tissue image quality, and volume geometry. In addition we have also performed the more “traditional” comparison of reconstructed volumes by removing a percentage of the input data. By using these evaluation methods and data from the specific scanner, the results showed that the processed video performed better than the digital scan-line data, digital video being better than analog video. Furthermore, the results showed that the choice of video source was more important than the choice of tested reconstruction algorithms.  相似文献   
212.
By using a digital image correlation technique, the full/local field strain in a brittle coating/ductile substrate system during tension has been successfully monitored. One of the most important experimental results indicates that the distribution of interfacial shear stress in the segmented coating is antisymmetric about the center, which clarifies several controversial assumptions introduced in theoretical models. Two key mechanical properties of thermal barrier coatings, fracture strength in coating and interfacial adhesion strength, were determined as 35.0 ± 4.6 and 14.1 ± 3.2 MPa, respectively, which are consistent with available experimental data.  相似文献   
213.
《Applied Mathematical Modelling》2014,38(19-20):4717-4732
In this paper, a communication scheme that could use a nonlinear dynamical system to create encrypted keys with an additional dimension is proposed, and the scheme could keep encrypted keys not to diverge. Since the divergence of encrypted keys (nonlinear signals) easily happens in non-linear systems coupled with other systems, the adaptive control approach, proposed in this paper, uses the universal state-space adaptive observer-based fault diagnosis/estimator and the high-performance tracker to eliminate the divergence of encrypted keys. At the same time, the receiver of communication retrieves informal messages by the universal state-space adaptive observer-based fault diagnosis/estimator and the high-performance tracker. Thus, this paper takes advantage of the merit of digital redesign methodology for a practical implementation of secure-communication, and the estimator solves the problem of secure communication. Thus developed a new approach could add more dimensions into nonlinear secure-communication systems without having the problem of divergence of encrypted keys.  相似文献   
214.
陈英 《科技信息》2013,(25):376-377
开发了一种智能型多功能入侵报警系统,该系既能完成传统的安防任务,也为小型图书室管理人员提供人性化提醒功能。与传统的视频监控系统相比,该系统侧重于事前和事中防入侵检测。整合四种类型的探测器,采用模块化设计,模块间采用无线加密通信,安全系数更高,防破解能力强。系统测试表明,各项功能达到设计要求。  相似文献   
215.
Applying the pulse laser to speckle methods, non-uniformities of the laser beam profiles and the intensities between each laser pulse have unpleasant consequences on the intensity distribution of the recorded images and following on the assigned fringes of the corresponding subtractive result. This contribution introduces a computer-based technique for compensating this technical and physical problem, so that the fringe quality is improved, even if the homogeneity of the laser beam profiles is on such low level, that the conventional (subtractive) technique fails. The solution is based on algorithms, which refines each intensity distribution and is comparable with the known shading correction.  相似文献   
216.
以中国知网(CNKI)数字出版物超市为数据统计源,手工收集并检索了2011-2013年《中华医学图书情报杂志》所发论文的栏目载文分布、基金资助情况、第一作者发文情况及合作度、作者地区分布、发文机构等,并用Excel软件对其进行了统计分析,以揭示该刊的学术质量和办刊特色。  相似文献   
217.
曲晶 《科技信息》2010,(29):I0206-I0207
概述了我国图书馆危机管理研究的现状,理清了我国图书馆危机管理研究的整个发展脉络,指出其存在的有关问题,探讨了图书馆危机管理研究的发展方向。  相似文献   
218.
潘成成 《科技信息》2011,(35):72-73
在信息技术十分发达的今天,高校图书馆文献的流动性逐步增强,完全具备了社会化的基本条件。实现高校图书馆的社会化,对于提升全民阅读率,提高图书馆馆藏资源的利用率,满足社会对信息资源的公共需求,具有重要的意义。高校图书馆的社会化是一项系统工程,本文将从高校图书馆社会化问题分析、外部环境优化、组织制度建设、公众意识提升等多个方面探究推进我国高校图书馆社会化建设。  相似文献   
219.
古新仪 《中国西部科技》2010,9(13):72-72,76
数字图书馆的建设应该基于"信息+网络+资源库+服务"的建设,因此,因应数字化图书馆建设的要求,对图书馆员队伍建设提出了五点新要求,相应地,其队伍结构的转变必须适应五个方面的转变。  相似文献   
220.
首先介绍了新兴的ISP(在系统编程)技术,ISP技术对数字系统的贡献以及ISP技术广阔的应用前景,提出在《数字电路》教学中引入ISP技术的方法和思路.  相似文献   
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