体数据可视化的加速光线投射算法

加速的体数据光线投射算法将光线在三维空间的采样问题看成光线的三维扫描转换问题，以层为基本的处理，避免了对三维体数据的随机检索，并且利用平行投影光线的方向都相同的特点，用查表快速实现了光线的三维扫描转换。该算法在微机上得到检验，它在重建时间和内存花费上都优于传统的实现方法。     

采用独立复位信号的同步时序电路可测试性设计

针对同步时序电路提出一种结合了插入可观测点的部分复位方法，该方法是基于迭代计算的电路状态信息和冲突分析测度而提出的．根据基于电路状态信息的测度和冲突分析所选择出来的部分复位触发器，可以割断电路中的关键回路，使得电路容易被初始化．同时减少在时序ATPG中的潜在冲突．以前的部分复位方法中，部分复位的触发器不能由独立的复位信号所控制，这也是不能彻底改善可测试性的一个重要原因．当部分复位触发器可以由独立的复位信号所控制时，电路的可测试性会显著提高．该文提出了一种新的可测试性结构来设计部分复位触发器，该方法同时减小了在管脚、延时和面积的开销。     

智能Agent在网络安全弱点检测系统中的应用

给出了一种基于智能Agent技术的安全弱点检测系统框架 ,该框架强调系统的智能性、扩充性、安全性、移植性及运行效率 ,同时分析了在Aglet平台实现中的关键技术。     

一种基于状态监测的防火墙

在OpenBSD系统上开发了一种基于状态检测的防火墙，并开发了内置的检测和防范几种常见网络攻击(syn flood、端口扫描、分片攻击、icmp flood、smurf)的功能。由于大多数这种攻击总是用假冒的源地址和随机的源端口来产生攻击包，因此这种防范模型比入侵检测系统的检测-修改防火墙策略模型更为有效。     

激光线扫描测量系统中物像对应关系的建立

提出一种基于样本线建立物像对应关系的标定法。该方法采用三棱柱作为标定块,标定块在标定范围内运动,得到样本线上的点。样本点的像由三棱柱两个棱面上的光带中心线用最小二乘法拟合直线求取交点的方法计算,所得像点到拟合样本线的最大偏差小于 0.1 像素。样本线将标定空间划分为 4 个子域,每个子域用线性插值的方法建立各自的映射关系。在自行设计的激光线扫描测量系统中采用该标定法,实际测量标准平面与球面的误差小于±0.05mm。     

基于AOTF技术的光纤损耗光谱检测系统设计

提出了一种新型的基于声光可调滤光器(AOTF)的便携式光纤损耗光谱检测系统。建立了光纤损耗光谱检测的数学模型和检测系统总体结构。该系统利用声光可调滤光器的电可调谐特性,采用DSP进行智能化控制,实现对光纤中信号光的快速光谱扫描,测量出被测光纤对不同波长的信号光的衰减特性。最后给出了实验结果和讨论。     

Optimizing imaging parameters for the separation of multiple labels in a fluorescence image

A theoretical analysis is presented on how to separate the contributions from individual, simultaneously present fluorophores in a spectrally resolved image. Equations are derived that allow the calculation of the signal‐to‐noise ratio of the estimates for such contributions, given the spectral information on the individual fluorophores, the excitation wavelengths and intensities, and the number and widths of the spectral detection channels. We then ask how such imaging parameters have to be chosen for optimal fluorophore separation. We optimize the signal‐to‐noise ratio or optimize a newly defined ‘figure of merit’, which is a measure of efficiency in the use of emitted photons. The influence of photobleaching on the resolution and on the choice of imaging parameters is discussed, as well as the additional resolution gained by including fluorescence lifetime information. A surprisingly small number of spectral channels are required for an almost optimal resolution, if the borders of these channels are optimally selected. The detailed consideration of photobleaching is found to be essential, whenever there is significant bleaching. Consideration of fluorescence lifetime information (in addition to spectral information) improves results, particularly when lifetimes differ by more than a factor of two.     

A study on sensitivity correction factor of gamma camera in whole body bone image

The aim of this study was to calculate a reasonable correction factor that could be corrected when the sensitivity of each gamma camera is measured and a whole body bone scan is performed as a follow-up examination. Seven pieces of equipment were used to analyse the sensitivity measurements of each gamma camera based on the source sensitivity measurement method recommended by the IAEA. These were BRIGHTVIEW, PRECEDENCE, ECAM, ECAM signature, ECAM Plus, SYMBIA T2 and INFINIA. The ^99mTc line source for the sensitivity measurement was generated in 4–7 kcps, which are the common values in a whole body bone scan. All the cameras were equipped with a low-energy and high-resolution parallel multi-hole collimator and set at a window width and photo peak of 15% and 140 keV, respectively. After placing the ^99mTc source as closely as possible to the collimator, the count was measured for 60 and 120 seconds to calculate correction factor. To determine if the correction factor calculated using the ^99mTc line source could be applied to a whole body bone scan of a real patient, a whole body bone scan was performed on 27 patients before applying the correction factor for comparative analysis. According to the experimental results using the ^99mTc line source, the gamma camera sensitivity was the highest for ECAM plus, followed in order by the gamma cameras, ECAM signature, SYMBIA T2, ECAM, BRIGHTVIEW, INFINIA and PRECEDENCE. When the results were used to calculate the correction factor based on the ECAM gamma camera, which had a medium-degree of sensitivity, the respective correction factors were 1·07, 1·05, 1·03, 1·00, 0·90, 0·83 and 0·72. The correction factors calculated based on the experiment using a ^99mTc line source were similar to those calculated based on the whole body bone scan. Clinical application of correction factor for measured sensitivity enables estimation of factor correction depending on difference in equipment when image is read, which improves accuracy and reliability of examination, and is expected to be used especially for continuous follow-up examination.     

基于跨度和虚拟层的三维芯核测试外壳扫描链优化方法

为减少三维芯核绑定前和绑定后的测试时间,降低测试成本,提出了基于跨度和虚拟层的三维芯核测试外壳扫描链优化方法.所提方法首先通过最大化每条测试外壳扫描链的跨度,使得绑定前高层电路和低层电路的测试外壳扫描链数量尽可能相等.然后,在TSVs(Through Silicon Vias)数量的约束下,逐层的将虚拟层中的扫描元素分配到测试外壳扫描链中,以平衡绑定前后各条测试外壳扫描链的长度.实验结果表明,所提方法有效地减少了三维芯核绑定前后测试的总时间和硬件开销.     

NoC边界扫描测试系统硬件设计

为了解决内部结构日益复杂的片上网络系统故障测试的问题,在研究3×3 2D-Mesh体系结构的NoC系统、边界扫描测试技术和资源节点故障类型的基础上,以FPGA为核心器件设计边界扫描测试系统。完成了数据采集、频率计、放大器、SRAM、IEEE1500 Wrapper等资源节点电路以及资源节点边界扫描链路的接口电路设计,并利用测试软件、信号发生器、万用表和数字示波器,通过边界扫描链路完成对整个硬件设计的测试。测试结果表明该设计性能稳定,为研究NoC系统的边界扫描测试技术提供了硬件平台。