现代ATS中可扩展的信号描述结构ATLAS2K

介绍IEEE颁布的新标准--ATLAS2K.ATLAS2K是ATLAS系列标准的最新版本,比早期版本有较大的改进,在原基础上提供了信号描述的组件库结构.它可迅速有效配备在采用其他标准的自动测试系统(ATS)中.     

The quiescent spectrum of 2S1636-536

During the EXOSAT observation of 2S1636-536 in July 1983 the quiescent flux was observed to brighten from 1.7×10 ^-9 ergs/cm. ² /sec to 2.6×10^-9 ergs/cm. ² /sec, this increase being accompanied by a decrease in effective temperature. Further analysis of the spectrum reveals that the best fit is a power law with an index which increases from -1.75 to-2.1 while the source brightens; there is some evidence for an upper cut off. This spectrum is interpreted as the result of soft photons from the neutron star surface which are Comptonised in a hot plasma cloud surrounding the neutron star (neutron star corona). The increasing spectral index is seen as the result of Compton cooling of the corona as the output of quiescent flux rises in response to an increasing accretion rate.     

Periodic X-ray outbursts from A0535+26, 2S1145-619 and GX301-2

We report Ariel V(SSI) observations of three X-ray pulsars A0535+26, 2S1145-619 and GX301-2 (2S1223-624). These sources exhibit X-ray outbursts which appear, on the basis of observations extending over 5 years, to have recurrence periods of 110 days, 187.5 days and 41.4 days respectively. If these periods are orbital in origin, the observed X-ray modulation may be explained in terms of an appreciable orbital eccentricity giving rise to time variable accretion. (In the case of GX301-2 published pulse timing data already provide independent evidence for a 41.4 day orbital period and an eccentricity e 0.4). The optical counterparts are all early-type stars; A0535+26 and 2S1145-619 are identified with Be main sequence stars and GX301-2 with a B2 supergiant which also shows an emission line spectrum. The implications of the observations in relation to possible mass transfer mechanisms in such systems are discussed.     

High latitude electrodynamics: Observations from S3-2

The high spatial-temporal resolution of instrumentation on the polar-orbiting S3-2 satellite has allowed a wide variety of measurements of the electrodynamic characteristics of both large- and small-scale structures at high latitudes. Analyses of large scale features observed by S3-2 have shown that: (i) The IMF B _ydependence of polar cap convection, first observed in June 1969 by OGO-6 persists in other seasons. During periods of northward IMF B _zextensive regions of sunward convection may be found in the sunlit polar cap. (ii) In the dawn and dusk MLT sectors >90% of the region 1 currents lie equatorward of the convection reversal line. Potentials across the ionospheric projection of the low-latitude boundary layer are typically a few kV. (iii) The location of extra field-aligned currents, near the dayside cusp and poleward of the region 1 current sheet is dependent on the IMF B _ycomponent. (iv) Simultaneous observations by TRIAD and S3-2 show that sheets of field-aligned current extend uniformly for several hours in MLT, but may have an altitude dependence in the 1000–8000 km range. (v) During magnetic storms ionospheric irregularities occur in regions of poleward density gradients and downward field-aligned currents near the equatorward boundary of diffuse auroral precipitation. In the winter polar cap, density irregularities were also found in regions of highly structured electric fields and soft electron precipitation. (vi) During an intense magnetic storm the auroral zone height-integrated Pederson conductivity was calculated to be in the range 10–30 mho and downcoming energetic electron fluxes accounted for between 50% and 70% of the upward Birkeland currents.Analysis of small-scale structures (latitudinal width < 1°), observed by S3-2, have shown that: (i) Intense meridional electric fields (50–250 mV m^-1) generated by charge separation near the inner edge of the plasma sheet drive intense subauroral convection and are associated with field-aligned currents, on the order of 1–2 A m^-2. (ii) Case studies of discrete arcs in the auroral oval have shown that arcs are associated with pairs of small-scale, field-aligned currents embedded in the large-scale region 1/region 2 field-aligned current sheets. The maximum observed field-aligned current was an upward current of 135 A m^-2, confined to a latitudinal width of 2km and carried by field-aligned accelerated electrons. Return (downward) currents associated with arcs are limited to intensities of 10–15 A m^-2. At this limit the ionospheric plasma becomes marginally stable to the onset of ion-cyclotron turbulence. Two instances of plasma vortices, characteristic of auroral curls, have been observed in the region between the paired current sheets. (iii) Sun-aligned arcs in the polar cap are found in a region of negative electric field divergence, embedded in an irregular electric field pattern. The electrons producing the arcs have a temperature of 200 eV and have been accelerated through potential drops of 1 kV along the magnetic field. Return currents may appear on both sides of polar-cap arcs.     

TFE731—2A-2A型发动机控制电路分析及典型排故模式

TFE731-2A-2A型发动机用于中巴联合研制的K8系列教练机上,它具有重量轻、推力大、耗油小、操纵简单等特点。本文对发动机控制电路一些典型故障进行了分析和归纳,可为外场使用维护TFE731—2A-2A型发动机提供参考。     

The X-ray source A0538-66 in optical quiescence

Summary Photometric observations of A0538-66 in quiescence show that the optical star is an object of equivalent spectral type B7eII. Spectroscopic data taken simultaneously confirm this spectral classification and are consistent with the reported periodic variations seen in the emission lines. It is unlikely that the optical outburst is due to X-rays reprocessed in the atmosphere of the primary star or elsewhere.     

The big dipper: 4U1624-49

We present a 6.3 hour observation of 4U1624-49 with the EXOSAT Medium Energy experiment. The X-ray light curve is dominated by a series of sharp dips in which the observed flux falls to 25% of the steady level on timescales of seconds. These dips are accompanied by strong variations in the spectral hardness consistent with large changes in the absorbing column density. No evidence is found for any dip periodicity, in contrast to the other four sources in which dip activity has been reported. We discuss the implications of these observations for models of low mass X-ray binaries.     

EXOSAT observations of bursts from 2S1636-536: Burst morphology

In two observations with the EXOSAT ME a total of 11 bursts were detected; 7 in July and 4 in May 1984. In terms of rise time and peak count rate there are only 2 kinds, those with a sharp rise and peak count rate of 500 cts/sec/detector and those with a slow rise and a peak count rate of 200 cts/sec/detector. The spectral analysis of these bursts shows a similar situation: for the sharp bright bursts the black body radius increases rapidly to > 20 km and the temperature lags. For the slow dim bursts the temperature rises ahead of the black body radius expansion which is small and slow. The time t _1/2 at which half the total burst energy has been released is 3.5 seconds for bright bursts and 8 seconds for dim ones. These gross differences may be related to the predominance of helium or hydrogen in the thermonuclear flash.     

The periodic X-ray transient A0538-66 and its optical counterpart

The long term light curve of the optical counterpart of A0538-66 is discussed, and a revised estimate for the period obtained. Observations of the optical spectrum during outburst and preliminary results from Einstein observations of two recent X-ray flares are presented.     

A330客改货即将来临

<正>空客A330客改货(P2F)项目启动于2012年,主要由空客集团和新科宇航的合资公司EADS EFW负责开发,目前各项进展顺利,初步设计评审(PDR)已于今年4月如期结束,下一个关键节点是关键设计评审需要在今年11月前完成,届时关键设计也将同步冻结。预计首套原型机组件将于2015年10月到位,首次改装预计会持续14个月,因此首架A330-300改装型货机将于2017年2月投     

Introduction [A century of powered flight:1903-2003]

The term Avionics is used loosely to identify that electronic equipment necessary to fly an aircraft. The term is nearly 50 years old with origins in military electronics. With the increasing dependence of aviation on electronics the amount of equipment that falls into this category has skyrocketed. This issue is intended to commemorate the Wright Brothers' Centennial of Powered Flight. It emphasizes aviation-related electrical/electronic advances for the years 1903 to 1953. The following paragraphs highlight some of the major topics discussed in this special issue.     

空客A330-200F货机诞生“恰逢其时”——航程更远,业载更高,满足不断变化的航空货运市场需求

2009年11月5日,空中客车A330-200F货机在法国图卢兹成功完成历时四个多小时的首次飞行。首飞成功之后,该飞机将进行长达180小时的飞行试验。     

B-2A轰炸机的隐身揭秘:电空气动力学

与Ｆ－１１７Ａ和Ｆ－２２隐身战斗机靠特别设计的多面体表面及吸波材料的被动隐身方式不同，Ｂ—２Ａ轰炸机应用的是以电空气动力学为基础的“主动”隐身技术。这也许就是Ｂ－２Ａ出厂之时，美军方发言人所说的已使美航空工业发生重大变革的技术内容之一     

EB~2:一种新型复合材料装配解决方案

复合材料在航空领域的大量使用带来了新的技术问题,由于这些材料的性能与"标准"金属不同,特别是要关注其损伤部位,因此重新考虑安装技术以获得有吸引力的机械性能、并使之相对易于操作是很有必要的。基于以上考虑,在阿基坦大区的支持下,Capaero与WCIE(西岸产业欧洲)和Bordeaux的LGM2B实验室一起针对机械工程和材料提出了这种EB2工艺方法。     

A380:便于维修的"庞然大物"

站在A380的前面,会被它巨大的尺寸所震撼。但要对它进行维护的人员来说,其各种可达性均得到了尽可能的优化。从某种程度上说,这种飞机尺寸的大幅增加即便是对于有多年工作经验的工程师来说也会引起担忧,怕会增加维护的复杂性和难度。但空中客车公司认为,A380飞机在许多方面可能较其他任何飞机更易于维修。按照航空公司的要求,在A380的设计过程中充分考虑了维护人员的生理状况和安全性。例如,任何质量超过25kg的物品均会安排两人或者由专用设备来运送。在飞机的周围及内部充分体现了人机工效学,应用复杂的虚拟人体模型,在飞机的数字模型(DM…     

Cockpit Instruments [A century of powered flight:1903-2003]

Since nearly the beginning airplanes were flown using only the stick or control column, rudder pedals, dials, and switches. There were as many control arrangements (sticks, wheels, and levers) as there were pioneer airmen. The 1903 Wright Flyer was far from conventional in many ways. Their only instruments were a stopwatch and prop revolution counter. Instruments were of little interest for about a decade after the Wright Brother's flight. Just getting off and back onto the ground safely was the primary concern. Controls have evolved, but not changed as much as instrument displays. The stick/control column is beginning to be replaced by hand controllers in some fly-by-wire (FBW) aircraft (e.g., Airbus A-320 and up). Servo feedback provides the necessary hand controller "feel" as a function of the aerodynamic pressure expected on the control surface.     

UAVs: the future. [A century of powered flight: 1903-2003]

Unmanned air vehicles (UAV) are assuming a prominent role in aviation and the future may have already arrived. Most of us have heard of the Global Hawk and Predator UAVs, which have been collecting real-time battlefield data without risking loss of life. However, the most amazing performance and avionics can be found in airplane-model-size MiniUAVs and insect-like MicroUAVs still on the drawing board. Meanwhile the all-electric NASA Helios "tower in the sky" is moving ever closer to reality.     

机场飞行区资源调度问题研究(二)：发展脉络与趋势

充分释放机场资源红利,发挥机场资源的最大效益,是空管、机场、航空公司、旅客和政府等航空运输各利益相关方的共同目标。本文聚焦机场飞行区资源调度的发展脉络与趋势问题,为飞行区资源调度问题研究系列之二。从明确资源总量、盘活资源存量、做强资源增量视角梳理飞行区资源调度的发展脉络,并对飞行区资源调度的一体化、高效化、智能化、协同化和绿色化发展趋势进行分析。研究成果旨在为机场运行管理理论与应用的可持续发展提供科学指引。     

A300-600自动油门系统衔接电门故障分析及排除

自动油门系统是用来控制飞机从起飞到着陆整个飞行全程的飞行速度控制装置,一旦出现故障,排故较困难。本文通过对该系统衔接电门故障排故过程的分析,提出对该系统维护的一些建议。