MRO信息技术的选择并非易事

尽管可选择的软件很多,但是解决实际问题正变得越来越困难。实践表明,使飞机维修数据达到自动化处理的水平是一个漫长而艰难的过程,而且没有万能的解决方案可以解决所有问题。一些航空公司,尤其是北美的一些航空公司,还在继续修补以前所用的如Maxi-Merlin和Sceptre等系统的漏洞。但是对于大多数新飞机来说,海量的数据以及法规监管的压力已迫使     

The relevance of economic data in the decision-making process for orbital launch vehicle programs, a U.S. perspective

Over the past fifteen years, major U.S. initiatives for the development of new launch vehicles have been remarkably unsuccessful. The list is long: NLI, SLI, and X-33, not to mention several cancelled programs aimed at high speed airplanes (NASP, HSCT) which would share some similar technological problems.The economic aspects of these programs are equally as important to their success as are the technical aspects. In fact, by largely ignoring economic realities in the decisions to undertake these programs and in subsequent management decisions, space agencies (and their commercial partners) have inadvertently contributed to the eventual demise of these efforts.The transportation revolution that was envisaged by the promises of these programs has never occurred. Access to space is still very expensive; reliability of launch vehicles has remained constant over the years; and market demand has been relatively low, volatile and slow to develop. The changing international context of the industry (launching overcapacity, etc.) has also worked against the investment in new vehicles in the U.S. Today, unless there are unforeseen technical breakthroughs, orbital space access is likely to continue as it has been with high costs and market stagnation.Space exploration will require significant launching capabilities. The details of the future needs are not yet well defined. But, the question of the launch costs, the overall demand for vehicles, and the size and type of role that NASA will play in the overall launch market is likely to influence the industry. This paper will emphasize the lessons learned from the economic and management perspective from past launch programs, analyze the issues behind the demand for launches, and project the challenges that NASA will face as only one new customer in a very complex market situation. It will be important for NASA to make launch vehicle decisions based as much on economic considerations as it does on solving new technical challenges.     

Globalization, commercial space and spacepower in the USA

Economic and commercial spacepower is about market dominance and control. The USA is still the largest investor in space in the world and the technological and commercial leader in many areas but its leadership is being challenged. When other nations have similar capabilities, control becomes a problem, assuming, as is the case with space, that control is also a critical issue in security. Moreover, exerting spacepower may be inconsistent with expanded commercial developments in space, raising investment risks and creating incentives for foreign competitors. To the extent that global market opportunity is denied by restrictive commercial policies, spacepower from a purely international economic competitive perspective is diminished. Though it is encouraging that the US commercial space policies have been in Presidential Documents over the past 20 years, they have been unintentionally undermined to a large extent by other policies, with security almost always trumping commerce. This paper examines the way globalization and commercial space developments have changed the nature of spacepower and suggests that the USA's reactions to these changes have not thus far served it well.     

Rebuilding US launch capabilities

Attempts to rebuild US commercial launch capabilities through stimulating private industry will be constrained by the fact that free-market competition does not really exist in the space industry. As the worldwide supply of launch vehicles grows, the policy now offered by the US government is only likely to fragment the US space launch vehicle industry. The author argues in favour of a proposal to establish a quasi-governmental corporation for space launches which would both safeguard the interests of government and commercial users and ensure that business acumen was applied.     

零备件需求预测至关重要

<正>在航空公司新的库存模式中,零备件需求预测软件、物流管理专家、零部件分销商、制造商将扮演着越来越重要的角色。在过去,航空公司为了保障航班的正常运营,会贮存大量的库存件。而现在,在激烈的市场竞争和高成本压力下,航空公司逐渐开始改变原有库存模式,寻求可靠的备件配送方式,以尽量缩短其周转时间。可靠的备件配送方式要求必须在正确的时间将正确的备件运送至正确的地     

Temperature-Driven Segmentation for Autonomous Anti-Tank Weapons

In this paper we discuss a simple temperature-driven segmentation technique that can be used for autonomous terminal guidance of anti-tank munitions. A ratio between two images from different IR bands is taken to form an emissivity independent image that is a function of temperature only. Size and temperature discrimination can then be used to find hot spots of interest. Candidate targets are segmented from the image about the points of interest using an.algorithm that finds all regions in multi-region objects and does not require a priori intensity information. Size and gross shape features are used to determine if the segmented objects are to be classified as targets. The key to this approach is the initial hot spot extraction. The temperature dependent ratio image allows quick and confident screening of the entire field of view, so that only the regions of interest require further processing. The described techniques effectively found tanks in the presence of common battlefield clutter when used with synthetic IR imagery provided by Georgia Tech Research Institute. The simplicity, effectiveness and potential speed of this technique make it ideal for autonomous guidance of expendable anti-tank weapons, especially where only low resolution IR imagery is available.     

Absolute Radiometer for the Flow Field of a Hypervelocity Projectile

As part of a hypervelocity instrumentation development program, it was desirable to include a radiometer system for measuring absolute radiation from projectile flow fields. A system employing a photomultiplier tube was designed, and laboratory and range experiments were conducted to investigate its performance characteristics. The laboratory experiments show that the linearity, saturation, and noise characteristics are suitable for this measurement; the system bandwidth is adequate to allow low frequency calibrations to be applied to high frequency measurements; and a derived expression for radiometer sensitivity variation as a function of photomultiplier supply voltage is reasonably correct. The results of the range experiments imply that the system response is sufficient to reproduce accurately input pulses as narrow as one microsecond and that a particular analytical technique for calculating the form of the radiative input to the radiometer from the projectile stagnation region is valid. Principles involved in the design of photomultiplier radiometer circuits of this type are discussed in detail.     

Ralph: A Visible/Infrared Imager for the New Horizons Pluto/Kuiper Belt Mission

The New Horizons instrument named Ralph is a visible/near infrared multi-spectral imager and a short wavelength infrared spectral imager. It is one of the core instruments on New Horizons, NASA’s first mission to the Pluto/Charon system and the Kuiper Belt. Ralph combines panchromatic and color imaging capabilities with SWIR imaging spectroscopy. Its primary purpose is to map the surface geology and composition of these objects, but it will also be used for atmospheric studies and to map the surface temperature. It is a compact, low-mass (10.5 kg) power efficient (7.1 W peak), and robust instrument with good sensitivity and excellent imaging characteristics. Other than a door opened once in flight, it has no moving parts. These characteristics and its high degree of redundancy make Ralph ideally suited to this long-duration flyby reconnaissance mission.     

MRO云平台的数据安全问题

<正>在数字化、信息化的推动下,航空维修领域的发展趋势之一是通过分析飞机和发动机等系统和部件的运营数据、维修数据来实现机队管理、效率提升、设计优化等。当前MRO领域活跃的数据云平台众多,如空客Skywise、波音AnalytX、罗罗Azure、GE Predix、汉莎技术Aviatar、法荷航Prognos。本文介绍了基于这些云平台的共享数据的使用、存储过程中的一些安保措施。     

Behavioral and biological effects of autonomous versus scheduled mission management in simulated space-dwelling groups

Logistical constraints during long-duration space expeditions will limit the ability of Earth-based mission control personnel to manage their astronaut crews and will thus increase the prevalence of autonomous operations. Despite this inevitability, little research exists regarding crew performance and psychosocial adaptation under such autonomous conditions. To this end, a newly-initiated study on crew management systems was conducted to assess crew performance effectiveness under rigid schedule-based management of crew activities by Mission Control versus more flexible, autonomous management of activities by the crews themselves. Nine volunteers formed three long-term crews and were extensively trained in a simulated planetary geological exploration task over the course of several months. Each crew then embarked on two separate 3–4 h missions in a counterbalanced sequence: Scheduled, in which the crews were directed by Mission Control according to a strict topographic and temporal region-searching sequence, and Autonomous, in which the well-trained crews received equivalent baseline support from Mission Control but were free to explore the planetary surface as they saw fit. Under the autonomous missions, performance in all three crews improved (more high-valued geologic samples were retrieved), subjective self-reports of negative emotional states decreased, unstructured debriefing logs contained fewer references to negative emotions and greater use of socially-referent language, and salivary cortisol output across the missions was attenuated. The present study provides evidence that crew autonomy may improve performance and help sustain if not enhance psychosocial adaptation and biobehavioral health. These controlled experimental data contribute to an emerging empirical database on crew autonomy which the international astronautics community may build upon for future research and ultimately draw upon when designing and managing missions.