快速合并分类算法的优化

本文介绍一种改进的快速合并分类算法及其在微机上的实现。在用各种比较操作进行分类的算法中,著名的合并分类(Merge Sort)法的分类速度最快,但它要以较大的额外存贮空间为代价。本算法与合并分类法相比,速度更快,而需要的额外存贮空间却减少了50％～67％。实验结果表明,N在500～1500范围内,速度提高了4.7％～8.5％,所需的额外存贮空间减少了51.2％～65.9％。本算法已在IBM PC机上用BASIC语言实现,可把本程序作为一个子程序加以调用。     

分布式容错系统的低冗余重构策略及拓扑结构研究

分布式系统需要采用合理的拓扑结构，才能在低冗余的条件下的实现容错，从而获得高的性能价格比。本文从分析的可靠性与重构策略的关系以及重构策略与系统拓扑系统入手，找出解决这一课题的一种途径，最后介绍了一个低余度高可靠实时重构的分布式容错系统的实现。     

点焊质量模糊控制系统研究

简要介绍了电阻点焊单片机微机模糊控制原理，确定了点焊模糊控制算法，分析了点焊模糊控制系统的硬件结构和软件设计。实验结果表明，该控制系统能够有效实现点焊质量的模糊控制，具有较强的自适应特性，可用于电阻焊智能制造。     

多维驱动微型振动平台的研制

一种以压电元件为驱动源,结合柔性铰链机构的微型振动平台,通过计算机设计控制电压波形,对其进行三维振动控制.通过实验证明,该机构具有良好的波形跟踪性能,易于实现复杂控制波形,适用于微型机械的动态性能测试.     

Status of solar sail technology within NASA

In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced. NASA has successfully completed functional vacuum testing in their Glenn Research Center’s Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L’Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails – perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was also conducted.     

Monitoring power supply current and using a neural network routineto diagnose circuit faults

As a circuit is tested, the current drawn from a power supply can vary as different functions are invoked by the test. The current draw can be plotted against time, showing a characteristic trace for the test performed. Sensors in the ATS power supply can be used to monitor the current flow during test execution. Defective components can be classified using a Neural Network according to the pattern of variation from the “trace” of a good card. This can be performed as a background function, with the network gaining in accuracy over time. This paper discusses the Neural Network Routine for diagnosing circuit faults using monitored power supply current     

ATE enabling technologies

A discussion of the current and emerging core technologies and philosophies that will enable Air Force personnel to quickly, accurately and intuitively diagnose faults in increasingly complex systems     

Imaging systems using modulation and coded aperture masks

The advent of improved γ-ray telescopes which incorporate high angular resolution imaging properties and adequate sensitivity will advance this branch of astronomy from the discovery phase to the exploratory phase. As in other fields, such as radio and X-ray astronomy, which have recently undergone this change, it will prove a fascinating era. The recent development of position sensitive γ-ray detection planes operated in conjunction with a suitable coded aperture mask have made γ-ray telescopes feasible which are capable of generating γ-ray images of the sky with a precision of 1 arc minute over the photon energy range 0.1 to 10 MeV. With a sensitivity of at least 1–10 milliCrab and scintillation standard spectral resolution not only can a large number of discrete γ-ray objects be identified and studied in detail but nuclear γ-ray line images of extended objects such as the Galactic Plane, Cloud Complexes, and supernovae remnants may be generated by this class of astronomical instrument.     

Spherical oscillation patterns

Spherical harmonics are an integral part of the study of stellar pulsations. To gain an understanding of how the star is affected by non-radial pulsations, the radial part of the oscillation is plotted, with an assumed sinusoidal time variation. The amplitude of the motion is arbitrarily set at 20% of the radius.     

电阻点焊电极位移监测系统的研究

采用可进行动态测量的ＬＳ型封闭式光栅位移传感器与微机测量单元，套电阻点焊电极位移系统。在不同焊接规范和焊接条件下所进行的电极位移特性测试结果表明，该系统方便、可靠地测取点焊过程电极位移，具有精度高、速度快等特点，适用于实际生产中点焊过程的质量控制。