AFM型频率计量自动测试装置

为了实现频率计量自动化测试,我所研制出一种AFM型频率计量自动化测试装置。它利用了廉价的PC-1500A袖珍计算机作为控制机,再加上适当的接口电路、驱动电路及两个1×16的高隔离度RF同轴多路开关,就可以构成一种多用途的实时自动数据采集系统,同时可以控制1-32台受检仪器。     

机载设备自动测试系统通用开发平台

针对当前自动测试系统(ATS,Automatic Test System)开发技术存在的不足,构建了一个ATS通用开发平台.该平台对ATS软硬件进行联合设计,用户只需通过接口输入被测设备信息及测试策略流程,平台即可自动完成大部分软硬件设计工作,包括仪器选型、适配器设计、测试程序生成等.设计结果会传递到平台提供的ATS运行环境,供用户进行被测设备的测试、故障诊断.经实例验证,ATS软硬件联合自动设计技术可缩短开发周期,降低开发成本,提高设计的标准化、通用化程度.      

基于VB6．0数据库下的示波器自动检定系统实现

以9500示波器自动检定系统为例,介绍了在VB6.0开发环境下,引用其强大的数据库功能。通过建立9500程控代码数据库、仪器登记数据库、检定参数设置信息库、检定结果信息库,实现了各库之间的数据访问和存储,达到了对各种示波器的半自动和全自动检定。并将部分代码加以介绍,可以直接在其它自动测试中应用,因此具有广泛的应用和借鉴价值。     

数字多用表自动检定系统设计

数字多用表型号多、功能多、检定项目多,每项具有多个量程,且各量程准确度不一,同一量程在不同检定点其技术指标也不尽相同,采用传统手动检定耗时耗力、误差大、错误几率高、工作效率低.在VEE Pro软件开发平台上,设计开发出一套数字多用表自动检定系统.该系统包括仪器信息记录、带接口数字多用表检定、不带接口数字多用表检定及打印输出四个模块,测试过程采用实时测试显示,自动进行数据处理并存档.使用结果表明:该系统操作简便,提高了工作效率及准确度,减小了人为误差,确保了测试数据准确可靠.     

隔离信号调理模块自动校准系统设计

针对隔离信号调理模块型号多、参量多、使用量大,采用手动计量校准耗时耗力、容易出错、工作效率低等问题,在VEE Pro软件开发平台上,设计开发出一套隔离信号调理模块自动校准系统。该系统包括仪器信息记录、校准及打印输出三个主模块,测试过程采用实时测试显示,自动进行数据处理并存档。使用结果表明：该系统操作简便,提高了工作效率及准确度,降低了人为出错几率,确保了测试数据准确可靠。     

通用电学参数自动校准系统接口研制

为了提高日常检定工作的工作效率,介绍一种基于LabVIEW平台下,以为接口的电学参数自动检定系统的组成、仪器控制方式及系统的特点。     

基于GPIB的示波器校准仪自动化检定系统的设计与实现

介绍了一种基于GPIB总线的示波器校准仪自动检定系统。通过GPIB总线接口将所有测试仪器与PC机连成一体,实现了对示波器校准仪的全自动检定。通过实验验证,与传统的手动检定相比,该系统大幅度地提高了示波器校准仪检定系统的检定精度和检定效率,具有广阔的应用前景。     

基于μ综合方法的运输机纵向自动着陆控制律

研究运输机的自动着陆问题,分析了运输机自动着陆的过程与特点,采用结构奇异值μ综合的控制系统设计方法,设计了运输机的二级自动着陆控制律,实现对理想下滑线精确跟踪;并对系统的鲁棒性进行了分析.仿真结果表明,在存在飞机模型不确定性,测量噪声和外界阵风干扰的情况下,所设计的自动着陆控制律满足运输机的自动着陆要求.     

运载火箭气液组合连接器动态自动对接技术

为实现未来重型运载火箭地面组合连接器与箭上接口的自动对接，提高发射准备流程安全性、可靠性，降低人员保障要求，开展了组合连接器自动对接的技术研究及总体策略分析，提出了由检测、智能控制、位姿调整系统组成的技术方案及非接触式检测+主动位姿调整+被动随动的自动对接策略，并开展了组合连接器自动对接试验系统研制，进行了组合连接器自动对接、低温加注、自动分离等全流程试验验证工作。结果表明:自动对接装置检测、智能控制、位姿调整等各项功能正常，自动对接策略准确、可行，解决了大载荷组合连接器在箭上接口大范围、高速运动条件下的自动对接难题，综合跟踪范围达±600 mm，综合跟踪速度达500 mm/s，各综合工况下完成自动对接时间约为3~5 min。      

用BC3—80微机实现光谱辐射量的自动测量

本文讨论了利用BC3-80微机(与TRS-80兼客)实现光谱辐射量自动测量的有关硬件和软件的设计问题,所用的方法适合于一般的自动测量情况,所得的结果是大大减轻了劳动强度,提高了测量精度和抗干扰的能力。     

Evolution of activity signatures during the main sequence phase

We review recent work on the decay of magnetic activity signatures, such as chromospheric/transition region/coronal emission as well as mean flare emission, with age for solar and later type stars. Both implicit and explicit evolutionary representations are discussed. In terms of magnetic flux, as measured by excess chromospheric CaII luminosity, we show that a simple dynamo-rotation relation that incorporates both a saturated state with its characteristic critical rotation (or scale factor) as well as an asymptotic linear power law, i.e. a scale free relation, fits the extant data that includes the dMe stars. Introducing the saturated dynamo state, as exemplified by the dMe stars, into activity power-power diagrams, allows us to not only specify the saturated state, but to define evolutionary tracks that represent the decay from the saturated state. Using the quiescent coronal X-ray power (luminosity) as a basic measure of magnetic activity, we find simple monomial relations for both the saturated state (linear) and for the evolutionary tracks governing both quiescent activity and mean flare activity. In particular, the coronal power loss is found to vary quadratically with the chromospheric power loss, hence with magnetic flux.     

The interaction of high-voltage spheres with the ionosphere

The interaction of a high-voltage sphere with both magnetized and unmagnetized plasmas was studied with an electrostatic fluid code. Simulations were conducted for a wide range of sphere and plasma parameters. Depending on the conditions, one can observe a propagating spherical double layer, an electron ringing, a stable rapidly-rotating electron density torus, as well as spherical and toroidal discharges.     

Evaluating the feasibility of GPS measurements of SSH on board a ship along the Portuguese West Coast

Aiming to validate coastal altimetry data, an exploratory experiment was carried out, using a survey ship with onboard GPS and motion compensation systems. The ship navigation plan followed a track as coincident as possible with the passage of two altimetry satellites, Envisat and Jason-1, along the Portuguese coast, in June 2007.     

PLC栈缓冲ASIC芯片的设计与实现

存贮管理是计算机体系结构的重要组成部分。对于Prolog和Lisp两种人工智能语言来说,它们的操作大多都是针对栈式存贮区进行的,因此一个高速的栈控制器将有效地提高它们的执行速度。本文简要介绍了Prolog/Lisp协处理器(PLC)栈缓冲机制的结构、原理以及栈缓冲专用芯片SC(Stack Controller)的设计方法和实现技术,为Prolog和Lisp语言的高效执行提供了一个性能价格比较高的存贮系统。     

Two energy release processes for CMEs: MHD catastrophe and magnetic reconnection

It remains an open question how magnetic energy is rapidly released in the solar corona so as to create solar explosions such as solar flares and coronal mass ejections (CMEs). Recent studies have confirmed that a system consisting of a flux rope embedded in a background field exhibits a catastrophic behavior, and the energy threshold at the catastrophic point may exceed the associated open field energy. The accumulated free energy in the corona is abruptly released when the catastrophe takes place, and it probably serves as the main means of energy release for CMEs at least in the initial phase. Such a release proceeds via an ideal MHD process in contrast with nonideal ones such as magnetic reconnection. The catastrophe results in a sudden formation of electric current sheets, which naturally provide proper sites for fast magnetic reconnection. The reconnection may be identified with a solar flare associated with the CME on one hand, and produces a further acceleration of the CME on the other. On this basis, several preliminary suggestions are made for future observational investigations, especially with the proposed Kuafa satellites, on the roles of the MHD catastrophe and magnetic reconnection in the magnetic energy release associated with CMEs and flares.     

窄线宽单频单偏振环行腔掺铒光纤激光器

为了获得稳定的窄线宽单频单偏振掺铒光纤激光器输出,对采用饱和吸收体的环行腔结构掺铒光纤激光器进行了研究.实验中采用未抽运掺铒光纤作为饱和吸收体形成窄带滤波器,并选用高反射率的光纤光栅作为波长选择元件,同时采用具有高消光比的保偏环行器来获得单偏振激光.窄线宽单频单偏振环行腔掺铒光纤激光器的峰值波长可以通过拉伸光纤光栅进行调谐,调谐的范围为1548~1552nm.当抽运功率为275mW时获得的输出最大功率55.4mW.通过采用光纤延迟自外差法的线宽测试技术测量出该环行腔掺铒光纤激光器的20dB线宽为3kHz,光纤激光器的输出光偏振态长时间稳定在偏振度99.9%.这种窄线宽单频单偏振掺铒光纤激光器可以作为相干激光雷达的稳定信号源.      

A new dynamical atmospheric ionizing radiation (AIR) model for epidemiological studies.

A new Atmospheric Ionizing Radiation (AIR) model is currently being developed for use in radiation dose evaluation in epidemiological studies targeted to atmospheric flight personnel such as civilian airlines crewmembers. The model will allow computing values for biologically relevant parameters, e.g. dose equivalent and effective dose, for individual flights from 1945. Each flight is described by its actual three dimensional flight profile, i.e. geographic coordinates and altitudes varying with time. Solar modulated primary particles are filtered with a new analytical fully angular dependent geomagnetic cut off rigidity model, as a function of latitude, longitude, arrival direction, altitude and time. The particle transport results have been obtained with a technique based on the three-dimensional Monte Carlo transport code FLUKA, with a special procedure to deal with HZE particles. Particle fluxes are transformed into dose-related quantities and then integrated all along the flight path to obtain the overall flight dose. Preliminary validations of the particle transport technique using data from the AIR Project ER-2 flight campaign of measurements are encouraging. Future efforts will deal with modeling of the effects of the aircraft structure as well as inclusion of solar particle events.     

Evaluation of light emitting diode characteristics for a space-based plant irradiation source.

Light emitting diodes (LEDs) are a promising irradiation source for plant growth in space. Improved semiconductor technology has yielded LED devices fabricated with gallium aluminum arsenide (GaAlAs) chips which have a high efficiency for converting electrical energy to photosynthetically active radiation. Specific GaAlAs LEDs are available that emit radiation with a peak wavelength near the spectral peak of maximum quantum action for photosynthesis. The electrical conversion efficiency of installed systems (micromole s-1 of photosynthetic photons per watt) of high output LEDs can be within 10% of that for high pressure sodium lamps. Output of individual LEDs were found to vary by as much as 55% from the average of the lot. LED ratings, in mcd (luminous intensity per solid angle), were found to be proportional to total photon output only for devices with the same dispersion angle and spectral peak. Increasing current through the LED increased output but also increased temperature with a consequent decrease in electrical conversion efficiency. A photosynthetic photon flux as high as 900 micromoles m-2 s-1 has been produced on surfaces using arrays with LEDs mounted 7.6 mm apart, operating as a current of 50 mA device-1 and at an installed density of approximately 17,200 lamps m-2 of irradiated area. Advantages of LEDs over other electric light sources for use in space systems include long life, minimal mass and volume and being a solid state device.     

有限推力变轨的月球探测器发射轨道设计

月球探测器的发射是一个多体问题,也是严格的轨道交会问题。发射轨道方案从理论上有很多种形式,但在工程应用中,受到火箭能力、发射场和测控条件等多种因素制约,方案选择限制非常严格。利用现有火箭,采用有限推力从停泊轨道转移发射是最常用的一种发射方式。本文以某典型火箭为例,对采用有限推力变轨方案的奔月轨道设计流程、发射方案、轨道设计方法、精度分析、发射窗口设计进行了详细分析和研究。     

Oscillations of axial plant organs.

The tips of roots and shoots commonly show lateral movements as they grow forwards. These occur as both circumnutations (with long periods and large amplitudes) and micronutations (with short periods and small amplitudes). Their properties are reviewed, with emphasis on roots, and possible ways in which they could be regulated are discussed. The mechanisms could include long-range controls (for circumnutations) that depend on transmissible signals using steps common to gravitropism, and short-range controls (for micronutations) that operate within the elongation zone. The former are a property of the apex as a whole, while the latter may be confined to localized groups of cells. Simulation of nutations is presented with a view to isolating key physiological processes. However, this approach is limited by the current inadequate understanding of the growth mechanisms involved.