千兆高速采集系统的硬件电路设计

运用美国国家半导体公司的超高速8位A/D转换器(ADC08D1000),配合Altera公司的高端FPGA(Stratix Ⅱ, EP2S60),实现高速双通道采集系统,每个通道的采样频率可达1 GHz.该采集系统的实现难点是硬件电路的设计和制作.本文重点介绍该采集电路的硬件设计,并对采集系统中由时钟抖动引起的噪声进行理论分析.     

内燃机车燃烧系统性能评估与预测

提出一种内燃机车燃烧系统综合性能评估和预测的新方法;燃烧系统的工作性能由柴油机功率、燃油消耗率、燃油压力、增压压力和排气温度等热工参数决定,介绍了有关参数的测量与计算,利用模糊理论对燃烧系统进行性能评估,利用灰色神经网络对燃烧系统的性能进行预测;该成果应用于株洲电力机车研究所研制的内燃机车状态监测与诊断系统,实际评估和预测结果验证了采用模糊理论进行性能评估和利用神经网络进行预测的可行性与有效性,与机车的其它诊断方法比较,能更全面地评估和预测燃烧系统的状态,为内燃机车检修提供了可靠依据。     

高压传感器的高动压校准研究

介绍了一种对高压传感器进行高动压校准的实验方法，该法的目的是为了检验高压传感器的高动态压力作用下工作一致性的性能，中筒要阐述了用于以上实验的液压脉冲发生器工作原理和结构，给出了装置的物理、数学模型和目前已投入使用的准动态校准装置的技术性能指标：压力峰值（２００－１００００）×１０＾５Ｐａ；产生压力波形为近似于半正弦的压力脉冲；压力脉冲宽度０．５－１５ｍｓ；重复性可达±０．６％。并给出利用该装置对     

一种采用方块脉冲函数求解延时最优控制问题的算法

本文采用方块脉冲函数方法,将线性延时系统二次型最优控制问题转化为函数极值问题, 得到了最优控制规律的分段恒定解答,导出了一种不同迭代求解的简便算法.所提算法对小 延时和大延时系统均有效.     

新型彩色金相仪的研制

本文介绍了一种新型彩色金相仪.通过一定的工艺,经它处理,可由普通的黑白金相图片得到彩色金相图,极大地提高了金相分析的分辨率.用此种仪器对一些试样进行了分析,取得了令人满意的结果.     

开发常规兵器模拟试验系统的意义和任务

充分运用现代科技手段,加速发展兵器模拟试验技术,开发常规兵器模拟试验系统,对于提高常规兵器的研制水平,改变过份地依赖“画图、加工、实弹试验”循环转磨的老办法,是使我国的常规兵器研制技术达到一个新的高度的重要举措,是一件急待我们大家努力去做的事．     

Targeted Tumor Hypoxia Dual‐Mode CT/MR Imaging and Enhanced Radiation Therapy Using Dendrimer‐Based Nanosensitizers

The efficacy of radiation therapy (RT) is often limited by the poor response of hypoxia inside most solid tumors. The development of a theranostic nanoplatform for precision‐imaging‐guided sensitized RT for tumor hypoxia is still challenging. Herein, the creation of hypoxia‐targeted dendrimer‐entrapped gold nanoparticles complexed with gadolinium(III) (Gd‐Au DENPs‐Nit) for dual‐mode CT/MR imaging and sensitized RT of hypoxic tumors is reported. In this work, generation 5 poly(amidoamine) dendrimers are partially conjugated with Gd(III) chelator, entrapped with Au nanoparticles, and conjugated with hypoxia‐targeting agent nitroimidazole via a polyethylene glycol linker, and ending with chelation of Gd(III) and conversion of their leftover amine termini to acetamides. The designed dendrimer‐based nanohybrids with 3.2 nm Au cores exhibit an excellent X‐ray attenuation effect, acceptable r₁ relaxivity (1.32 mM^?1 s^?1), and enhanced cellular uptake in hypoxic cancer cells, affording efficient dual‐mode CT/MR imaging of tumor hypoxia. Under X‐ray irradiation, the Gd‐Au DENPs‐Nit nanohybrids can produce reactive oxygen species, promote DNA damage, and prevent DNA repair, facilitating sensitized RT of hypoxic cancer cells in vitro and tumor hypoxia in vivo. The developed hypoxia‐targeted dendrimer‐based nanohybrids may be employed as both contrast agents and nanosensitizers for precision tumor hypoxia imaging and sensitized tumor RT.     

一种基于文本检测的书脊定位方法

书脊定位是实现图书管理自动化的重要技术,通过对定位分割出的书脊图像进行图像匹配或文本识别获得图书信息,可大大减小图书检索、整理的人力劳动。论文提出了一种基于文本检测的书脊区域粗选方法,首先通过序贯分割算法检测图像中的字符整体区域,然后根据字符宽度和距离将同属于一本书的字符加入相似字符集合,根据集合内的字符中心和字符宽度计算候选书脊区域,最后通过支持向量机分类器精选书脊区域。相比于已有的书脊定位方法,论文算法在光照敏感、相邻书脊颜色对比度敏感、书脊多角度倾斜检测等方面进行了改善,在实验中取得了较好的定位成功率。     

淮安市灌溉水利用系数推求分析及调控增效措施研究

通过选取典型样点灌区对淮安市各县(区)灌溉水利用系数进行推算,进而分析各县(区)灌溉水利用系数现状水平及其对淮安市整体灌溉水利用系数的影响。结果表明,清浦区、洪泽县、金湖县和盱眙县典型样点灌区灌溉水利用系数空间分布较为均匀,上下浮动约0.01;同一地区提水灌区的灌溉水利用系数均处于较高水平;各县(区)灌区的灌溉水利用系数与灌区规模成负相关关系;淮安区、洪泽县是提高淮安市灌溉水利用系数水平的关键地区。并以此为依据,提出工程、技术、管理三方面的增效措施。     

Automatic recognition of serial numbers in bank notes

This paper presents a new topic of automatic recognition of bank note serial numbers, which will not only facilitate the prevention of forgery crimes, but also have a positive impact on the economy. Among all the different currencies, we focus on the study of RMB (renminbi bank note, the paper currency used in China) serial numbers. For evaluation, a new database NUST-RMB2013 has been collected from scanned RMB images, which contains the serial numbers of 35 categories with 17,262 training samples and 7000 testing samples in total. We comprehensively implement and compare two classic and one newly merged feature extraction methods (namely gradient direction feature, Gabor feature, and CNN trainable feature), four different types of well-known classifiers (SVM, LDF, MQDF, and CNN), and five multiple classifier combination strategies (including a specially designed novel cascade method). To further improve the recognition accuracy, the enhancements of three different kinds of distortions have been tested. Since high reliability is more important than accuracy in financial applications, we introduce three rejection schemes of first rank measurement (FRM), first two ranks measurement (FTRM) and linear discriminant analysis based measurement (LDAM). All the classifiers and classifier combination schemes are combined with different rejection criteria. A novel cascade rejection measurement achieves 100% reliability with less rejection rate compared with the existing methods. Experimental results show that MQDF reaches the accuracy of 99.59% using the gradient direction feature trained with gray level normalized data; the cascade classifier combination achieves the best performance of 99.67%. The distortions have been proved to be very helpful because the performances of CNNs boost at least 0.5% by training with transformed samples. With the cascade rejection method, 100% reliability has been obtained by rejecting 1.01% test samples.