网络并行计算平台新架构*

网络并行计算的编程要求设计者对任务的分解、分配及子任务间的交互等问题有更高的技术。给出了在网络并行计算的一种新平台,用户只需提交数据和对它的操作即可。     

扩展Oracle Spatial实现跨服务器的空间数据管理*

海量空间数据的管理需要多服务器的支持,空间数据的跨服务器操作是必须解决的关键问题。针对Oracle数据库系统的Client／Server体系在管理跨服务器空间数据中存在的问题,利用远程内嵌过程和触发器等相关技术,设计并扩展了Oracle Spatial的功能,实现了基于Oracle的空间数据跨服务器分布式管理。     

三维图形生成软件POV-RAY的原理及应用

本文介绍了一种国际上广泛采用的三维图形生成软件ＰＯＶ－ＲＡＹ。该软件是为学术研究和教学研制的。它是免费、公开原代码的基于光线跟踪原理软件包。本文介绍了该软件的特点,各项功能及其与其他三维图形软件的区别。着重描述了场景描述语言的各部分结构：头文件、照相机定义、光照定义、物体描述等。根据我们的使用认为ＰＯＶ－ＲＡＹ的功能齐全、使用方便。不但可以用于生成各种三维图形,还可以作为二次开发的理想平台或参考系     

人工智能技术在海关系统的应用

本文在介绍人工智能技术的同时 ,也阐述了人工智能在一些领域的应用 ,并以海关系统为例。当今计算机软件和硬件的迅速发展 ,网络技术与人工智能技术的兴起 ,对海关系统的科技发展将会产生重大的推动作用 ,在现代海关业务信息化管理系统中 ,尤其是布控系统管理模块 ,它体现了一些人工智能技术的应用 ,当然 ,该系统在今后的应用中将会进行不断的改进和完善。     

A six-wafer combustion system for a silicon micro gas turbineengine

As part of a program to develop a micro gas turbine engine capable of producing 10-50 W of electrical power in a package less than one cubic centimeter in volume, we present the design, fabrication, packaging, and experimental test results for the 6-wafer combustion system for a silicon microengine. Comprising the main nonrotating functional components of the engine, the device described measures 2.1 cm×2.1 cm×0.38 cm and is largely fabricated by deep reactive ion etching through a total thickness of 3800 μm. Complete with a set of fuel plenums, pressure ports, fuel injectors, igniters, fluidic interconnects, and compressor and turbine static airfoils, this structure is the first demonstration of the complete hot flow path of a multilevel micro gas turbine engine. The 0.195 cm³ combustion chamber is shown to sustain a stable hydrogen flame over a range of operating mass flows and fuel-air mixture ratios and to produce exit gas temperatures in excess of 1600 K. It also serves as the first experimental demonstration of stable hydrocarbon microcombustion within the structural constraints of silicon. Combined with longevity tests at elevated temperatures for tens of hours, these results demonstrate the viability of a silicon-based combustion system for micro heat engine applications     

Solving equations by hybrid evolutionary computation techniques

Evolutionary computation techniques have mostly been used to solve various optimization and learning problems. This paper describes a novel application of evolutionary computation techniques to equation solving. Several combinations of evolutionary computation techniques and classical numerical methods are proposed to solve linear and partial differential equations. The hybrid algorithms have been compared with the well-known classical numerical methods. The experimental results show that the proposed hybrid algorithms outperform the classical numerical methods significantly in terms of effectiveness and efficiency     

Evolutionary ensembles with negative correlation learning

Based on negative correlation learning and evolutionary learning, this paper presents evolutionary ensembles with negative correlation learning (EENCL) to address the issues of automatic determination of the number of individual neural networks (NNs) in an ensemble and the exploitation of the interaction between individual NN design and combination. The idea of EENCL is to encourage different individual NNs in the ensemble to learn different parts or aspects of the training data so that the ensemble can learn better the entire training data. The cooperation and specialization among different individual NNs are considered during the individual NN design. This provides an opportunity for different NNs to interact with each other and to specialize. Experiments on two real-world problems demonstrate that EENCL can produce NN ensembles with good generalization ability.     

LUGB系列涡街流量变送器的检测放大器

介绍了LUGB系列涡街流量变送器的核心部件 -检测放大器的电路分析。主要论述了该流量变送器的测量原理及检测放大器的电路组成与工作原理。通过实际应用证明 :该检测放大电路在测量范围、测量精度上都达到了一定的要求。     

化学链燃烧技术的研究现状及进展

介绍了化学链燃烧技术的基本概念,总结了现存的载氧剂及其制备方法,指出NiO/NiAl2O4、Fe2O3/Al2O3和CoO-NiO/YSZ是较为理想的金属载氧剂;介绍了4种化学链燃烧反应器模型,指出对能够长期稳定运行的反应器有待进一步研究;概括了化学链燃烧的耦合系统,通过模拟仿真得出其最高系统效率有望达到55.9%;最后,指出化学链燃烧技术可以向固体燃料燃烧、制氢方向发展.     

钡盐产品的研究开发和展望

介绍了国内外主要钡盐产品的研究开发现状和生产状况 ,并且阐述了主要的钡盐产品的应用前景和市场动态趋势