大清河系“7·21”洪水断想

借助"7·21"洪水的发生,通过对华北地区可能干旱和洪涝交替出现的判断,提出了大清河系在防洪工作中存在的不足,及时为可能出现的洪涝灾害提出预警。     

DSP在数据链终端机安全中的应用

随着战争形态的发展,信息化已经成为制约战争成败的关键因素.数据链是信息化战争所依赖的重要平台.针对数据链的需求,设计了一种用于数据链终端机的数据安全模块,在PXI总线平台上实现了相对独立的数据加解密处理,叙述了模块的设计思想、功能和基本工作过程.     

套管式直流蒸汽发生器动态特性仿真研究

套管式直流蒸汽发生器是一种采用双面传热的新型蒸汽发生器.在中心管和环管外侧与环形通道流体间热流密度相等的假设基础上,合理选择集中参数并应用可动边界的处理方法对套管式直流蒸汽发生器传热管进行了动态仿真.仿真结果与热工水力定性机理分析结果及相关的试验结果相符,从而验证了仿真方法是有效的.     

A general fan-beam reconstruction algorithm for free-form trajectories

In this paper we develop a general exact fan-beam reconstruction algorithm for free-form trajectories not only closed but also unclosed, based on the fan-beam reconstruction formula recently developed by Noo et al.. A mathematical proof is then provided with the geometrical explanation of equi-spatial detectors. With this algorithm we can obtain exact region of interest (ROI) reconstruction if and only if every projecting line passing through the ROI intersects the free-form source trajectory, when the projections are not truncated. Furthermore, under the condition that the source-to-detectors distance changes slowly enough relative to the length itself, we obtain a very good approximate reconstruction algorithm, which is the same as the algorithm of the circular trajectory except that the source-to-detectors distance is a function of the rotation angle. Then the algorithms are tested using the Shepp-Logan phantom and the experiment shows that the algorithms can get perfect numerical results.     

移动式~(37)Ar快速测量原型系统演示总结报告

研制了用于全面禁止核试验条约现场视察的移动式37Ar快速测量原型系统。进行了移动式37Ar快速测量原型系统演示活动。演示活动通过车载运输、模拟样品快速分离纯化测量、地下样品快速取样分离纯化测量、取样有效性四个场地试验和三次实验室验证测试,全面展示和验证了移动式37Ar快速测量原型系统的技术状态和性能指标。演示结果表明:移动式37Ar快速测量原型系统最小探测下限满足探测当量大于1kt的地下核试验的要求,且具有“机动、快速、小型”的特点,但系统仍需在降低探测限、增强稳定性和自动化程度等方面开展进一步研究工作。     

中小型铝电解厂供电系统调度运行方式的探讨

公司2 0 0kA电解槽投产后,用电负荷增大,自备电厂负荷小,不能满足生产需求,由于所在地区电网薄弱,供电不稳定,特别是遇到发、供电设备检修和突发故障时,电流强度波动大,对电解槽生产影响较为严重。根据这种现状,经过长期运行实践,制定了不同设备检查及故障状态下35kV发、供电系统生产调度运行的最佳方式,保证了企业正常生产,提高了企业经济效益     

Effect of AlP master alloy on grain refinement of primary silicon in eutectic Al-Si alloys

To obtain the finer primary silicon crystals, the proprietary Al-P master alloy was adopted to modify the eutectic Al-Si alloys and the most suitable modification process was made in the experiments. The SEM (Scanning Electron Microscope) and DSC (Differential Scanning Calorimeter) analysis indicate that the Al-P modifier has more advantages over Cu-P and Fe-P modifier in easily addition, no elemental alteration and less undercooling of primary silicon′s solidification, which suggests the Al-P master alloy is an effective modifier of eutectic Al-Si alloys.     

聚乙烯醇复合膜的制备

以亲水性的聚乙烯醇为原料，采用机械涂敷法制备复合纳滤膜．考查了基膜、聚乙烯醇的浓度、交联剂的浓度及配比、涂层厚度、交联时间以及热处理等对膜分离性能的影响，确定了最终制备条件．在一定的温度和湿度条件下，在截留相对分子质量为100000的基膜上，通过5％的聚乙烯醇溶液与1％的戊二醛的交联反应，研制了截留相对分子质量为600的PVA复合纳滤膜。     

直驱式电液位置系统PID控制的研究

针对直驱式电液位置系统的特点，使用PID控制改善系统的特性。经过对比分析，采用不完全微分PID控制策略。通过仿真在不同负载下系统对阶跃和斜坡信号的响应，分析结果得出：采用PID控制方法后带载系统响应时间、稳态误差变小，系统刚度增大，减小了负载带来的影响，能够达到控制的需要。     

Embodied categorisation for vision-guided mobile robots

This paper outlines a philosophical and psycho-physiological basis for embodied perception, and develops a framework for conceptual embodiment of vision-guided robots. We argue that categorisation is important in all stages of robot vision. Further, that classical computer vision is unsuitable for this categorisation, however, through conceptual embodiment, active perception can be effective. We present a methodology for developing vision-guided robots that applies embodiment, explicitly and implicitly, in categorising visual data to facilitate efficient perception and action. Finally, we present systems developed using this methodology, and demonstrate that embodied categorisation can make algorithms more efficient and robust.