医用直线加速器获取锥形束CT的图像空间扩展技术

提出了一种改进的锥形束CT(CBCT)图像获取流程,并在此基础上开发算法实现了CBCT图像的空间扩展.对实现算法进行了详细描述,并从放射剂量学角度对用于放射剂量计算可行性进行验证,相同放疗计划下对比胸部计划CT和扩展CBCT剂量计算结果表明,全肺受照射剂量大于等于20Gy的相对体积平均相差0.5%±0.22%,全肺平均受照射剂量平均相差(38.2±8.82)cGy,因此认为扩展后CBCT图像用于放射剂量计算与计划CT无显著差异.该技术拓宽了锥形束CT在影像引导放射治疗中的应用范围,提高了肿瘤放射治疗的精度,为开展自适应放疗、准确评价放疗计划提供了科学手段,有广泛的临床应用前景.由此带来的更多低剂量辐射对患者正常器官及皮肤造成的损伤有待进一步开展临床研究.     

高成长性:企业加速器的毕业标准

处于成长期的企业,经过一段时期专业化的"加速"服务,将面临着从加速器"毕业"的问题。高成长性是企业加速器毕业标准的核心,其内涵包括环境适应能力增强、内部管理优化、技术创新升级、价值网络形成与规模迅速扩张五个方面。     

Aptix硬件仿真器

随着设计复杂程度的增加，RTL级仿真验证时间大幅度增加，已经成为设计的瓶颈．使用硬件仿真器可以加快仿真速度，提高仿真效率，是设计百万门以上电路的不可或缺的工具．     

静电加速器真空度的检测与安全防护

设计和调试了一套静电加速器真空度检测和控制装置.该装置能够在计算机上显示当前真空度,可以设置合适的安全气压.当真空腔体内气压大于安全气压时,它可以自动关闭加速器电源,从而保证静电加速器安全可靠地工作.     

促进剂对热过滤法回收铜渣氯浸渣中硫的影响

将促进剂应用于热过滤法回收铜渣氯浸渣中硫的研究.研究促进剂种类、热过滤温度、渣剂质量比、保温时间对回收渣中硫的影响.结果表明:使用单一促进剂四乙基二硫代秋兰姆,硫的回收率为76.35%;使用单一促进剂2-硫醇基苯并噻唑,回收率为76.4%;采用四乙基二硫代秋兰姆和2-硫醇基苯并噻唑的复合促进剂,其总的渣剂质量比20∶5,四乙基二硫代秋兰姆与2-硫醇基苯并噻唑的质量比1∶2,温度为135℃,保温时间为30min时,硫的回收率可达91.89%,纯度为99.06%.     

Architecture Design of Computing Intensive SoCs

Most existing system-on-chip (SoC) architectures are for microprocessor-centric designs. They are not suitable for computing intensive SoCs, which have their own configurability, extendibility, performance, and data exchange characteristics. This paper analyzes these characteristics and gives design principles for computing intensive SoCs. Three architectures suitable for different situations are compared with selection criteria given. The architectural design of a high performance network security accelerator (HPNSA) is used to elaborate on the design techniques to fully exploit the performance potential of the architectures. A behavior-level simulation system is implemented with the C++ programming language to evaluate the HPNSA performance and to obtain the optimum system design parameters. Simulations show that this architecture provides high performance data transfer.     

An efficient electronic marketplace bidding auction protocol with bid privacy

The multiagent negotiation testbed proposed by Collins was modified. It utilizes publish/subscribe system, timerelease cryptography and anonymous communication. The proposed protocol reduces DOS attack and avoids replay data attack by providing ticket token and deal sequence number to the supplier. And it is proved that generating random number to the supplier by market is better than the supplier doing it by him in guaranteeing anonymity. Market publishes an interpolating polynomial for sharing the determination process data. It avoids collusion between a customer and a certain supplier. According to the comparison and analysis with other protocols, the proposed protocol shows good security and better efficiency.      

提高"强光一号"驱动Z箍缩负载电流的研究

“强比一号”加速器是目前国内输出功率最大的一台组合式多用途高功率强流脉冲电子束加速器。在该加速器上开展高功率Z箍缩产生X射线的技术研究时,需要调整提高“强光一号”驱动电流。主要介绍提高“强光一号”加速器输出电流的理论与实验研究。建立了计算模拟加速器工作过程的电路模拟程序,并在模拟计算的指导下开展了大量的实验研究,在短路电感15nH真空负载上获得了脉冲前沿小于100ns,峰值约3．0MA的脉冲电流,在优化设计的Z箍缩负载上得到了脉冲前沿小于100ns,峰值约2．2MA的脉冲电流．     

静电粒子加速器中束流光路的计算与设计

设计、优化静电加速器需要对其束流光路进行精确计算,现有束流输运程序不能对束流经过某些复杂结构极面的电磁元件进行模拟。该文比较了不同输运程序,扩展了通常仅用于模拟离子源引出的Igun程序,对束流经过静电透镜进行了计算。根据Poisson/Superfish、Parmela程序的特点,对特殊的静电元件,用前者计算电场,再导入Parmela程序进行整个光路的模拟计算。该方法可以计算束流经过复杂极面的电磁元件作用后的传输特性。实例计算表明,靶点束斑直径约为1cm,与实际测量结果比较吻合。