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Mathematical modeling and control of artificial ecosystems, such as MELISSA, require first the study of physical and biological characteristics in optimal and limiting conditions. Following the previous determination of the stoichiometric equations (Spirulina compartment) and regarding the two phototrophic compartments of MELISSA (Rhodospirillaceae and Spirulina), we have first to focus our control study on the growth kinetics for the light source. In this paper, we recall the theoretical equations of microbial growth kinetics and emphasise the problem of the light transfer in a photobioreactor. We present their adaptations to our pilot plant taking into account technological and biological specifics (lamp spectrum, working illuminated volume, growth rate,…). We then develop the principles and structure of the control system and describe tests of both the hardware and software for several steady state configurations.

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.

THIS PAPER is concerned with design problems which are encountered on manned aircraft operating at very high speeds. Very high speeds are considered to be from Mach 2 or 1300 mph to speeds of the order of Mach 38 or 25,000 mph, which is the velocity for escape from the earth. Mach 2 is considered a logical starting point since it represents the approximate upper limit of present day military aircraft. Manned aircraft will continue to be developed for flight at very high speed and high altitudes and the experiences gained will serve as stepping stones to eventual manned satellites and space vehicles. The major problems to be solved relate to aerodynamic heating, stability and control, and human effects. This paper received the 1958 Wright Brothers Medal.

This paper describes the ZENITH Nano-Satellite cum planetary atmospheric entry vehicle, called CanSat, the first Nano-Satellite project that has been developed by Delhi Technological University (Formerly Delhi College of Engineering), India. The satellite will function for monitoring the concentrations of various gases in the atmosphere. For this, the satellite consists of arduino microcontroller interfaced with the various Micro-electromechanical system (MEMS) gas sensors for measuring the concentrations of various gases such as carbon dioxide, carbon monoxide, methane, nitrous oxides, ozone, etc. The data obtained from the CanSat will be transmitted to the ground station where all the data will be stored and also the locations will be stored using GPS sensor. The academic goal of this project is to recruit students to the field of space science and technology.

The XMM-NEWTON satellite is the ESA X-ray spaceborne observatory covering the soft X-ray portion of the electromagnetic spectrum. XMM-NEWTON has been put in orbit on December, 10th 1999 by an Ariane 5 single launch. The spacecraft has a conventional thermal design that takes full advantage of the stable environment provided by its high altitude/long period orbit and by the limited variation of solar attitude angles in order to provide a stable platform for the telescope system. The precise geometry and alignment of the telescope system impose strict temperature requirements so that not only temperature gradients have to be kept small but also, and more importantly, time-variations of the gradients have to be minimised. In the paper, the thermal behaviour of the spacecraft as verified by its thermal test programme is compared with the early in-orbit temperature measurements.

In October of 1997, the Federal Communications Commission (FCC) granted two national satellite radio licenses. The FCC allocated 25 MHz of the electromagnetic spectrum (2.3 GHz frequency band) for satellite digital broadcasting to two companies: 12.5 MHz to XM Satellite Radio and 12.5 MHz to Sirius Satellite Radio. This paper is an overview of the XM Satellite Radio technology. Four major components of the overall Network are described: a) The ground segment; b) The space segment; c) The terrestrial repeater segment and the d) The technology segment. Mobile antenna design challenges are also being addressed and optimum antenna configurations are presented.

The X-29A is the first X-series experimental aircraft developed in the United States since the mid-sixties. The X-29A is a technology demonstrator aircraft that integrates several different-technologies into one airframe. Among the technologies demonstrated are the aeroservoelastically tailored composite forward swept wings, close coupled canards, discrete variable camber wing, triplex digital flight control system with analog backup, thin supercritical wing, three surface pitch control, large negative static margin and the integration of these technologies into the X-29 airframe. This paper deals with the issue of technology integration of five of the X-29A subsystems and the early design decision to use existing aircraft, components whenever and wherever possible. The subsystems described are the X-29 aircraft Hydraulics System, the Electrical Power System, the Emergency Power System, the Aircraft Mounted Accessory Drive and the Environmental Control System.

Selection of working fluid is one of the main criterions for designing of heat pipes thermal control systems (TCS) for space application. In this paper we will describe how we solved the task of development of the TCS with working fluid of high thermal physical properties. In 2004-2006 we developed the Engineering model of Deployable Radiator based on Loop Heat Pipe by CAST purchase order. It was developed for qualification tests. Ammonia application as LHP working fluid is stipulated by its high thermal physical properties. However Ammonia freezing temperature is of minus 77ºC. Such fact impedes Ammonia application when operation temperatures of LHP Radiator are lower than this value, for example, It takes several tens of hours to orbit a spacecraft and prepare it for work (at that moment the spacecraft is out of power supply) and the working fluid can be frozen in a condenser-radiator when the spacecraft being in the shadow over a long period of time.

This specification covers all aspects from the selection through installation of wiring and wiring devices used in aerospace vehicles. Aerospace vehicles include airplanes, helicopters, lighter-than-air vehicles, and missiles.

This specification covers all aspects from the selection through installation of wiring and wiring devices used in aerospace vehicles. Aerospace vehicles include airplanes, helicopters, lighter-than-air vehicles, and missiles.

This specification covers all aspects in Electrical Wiring Interconnection Systems (EWIS) from the selection through installation of wiring and wiring devices and optical cabling and termination devices used in aerospace vehicles. Aerospace vehicles include manned and unmanned airplanes, helicopters, lighter-than-air vehicles, missiles, and external pods.

This specification establishes process controls for the repeatable production of preforms by Wire Fed Plasma Arc Directed Energy Deposition (PA-DED). It is intended to be used for aerospace parts manufactured using Additive Manufacturing (AM) metal alloys, but usage is not limited to such applications.

This specification establishes process controls for the repeatable production of preforms using the wire fed laser directed energy deposition (L-DED-wire) process for additive manufacturing. Preforms are intended to be used to manufacture aerospace parts, but usage is not limited to such applications.

Wind tunnel tests have been carried out to develop a spoiler lateral control system for use with the GA(W)-1 airfoil with a 30% Fowler flap. Tests show that unfavorable aerodynamic interactions can occur between spoiler and flap for large flap deflections. Providing venting of lower surface air through the spoiler opening substantially improves performance. Results of tests with a number of spoiler and cavity shapes are presented and discussed. Applications of two-dimensional wind tunnel results to the design of satisfactory manual lateral control systems are discussed.

Through this work, Wind River and Airbiquity look to enable secure and intelligent software updates and data management for these vehicles through over-the-air (OTA) programming technology. The work may also lead to similar solutions for traditional aerospace and unmanned aircraft system (UAS) industries.

Use of air freight depends not on the commodity or industry, as such, but on the combinations of characteristics that enable company to benefit from air shipment in any particular situation. Air freight handling and control systems should augment, not decrease, these benefits. Future air freight traffic must be forecast in terms of the different benefits sought in shipping by air. Research is required to determine the relative importance of different benefits in future traffic generation. Research areas are defined and cooperative research efforts urged.

A lengthy effort to develop the minimum operational requirements of avionics systems needed for participation in the air traffic control system has not yet yielded standards or a means of administration acceptable to all segments of aviation. A new, more palatable approach by which users of the airspace can provide certain minimum operational characteristics in their airborne electronic systems shows promise. In order to make it work, FAA must clearly describe its electronic systems, how they work, and what their limitations are, so that willing participants may find out what they need to do in order to be right. Based on these system standards, minimum operational characteristics of airborne avionics can be developed and implemented. These may then meet with the approval of most of those affected, since the requirements will merely represent their own self-interest.

Before considering the future of aircraft environmental control systems (ECS's), a review of the relatively short history of this field would be valuable in understanding the present situation. Therefore, this paper notes many of the significant developments in commercial aircraft air-cycle refrigeration and in cabin environmental control. The evolution leading to the great variety of air-cycle systems now in production, or under development, is discussed along with a generic comparison of the merits of the various system types and some reasons for their selection. Constraints on air conditioning system development imposed by the airline operators, aircraft manufacturers, and regulatory agencies are touched upon as significant to charting the future direction of air conditioning system design. Finally, several directions that could be taken in future design are briefly commented upon.

To prepare for the leap from low-Earth orbit habitation to deep space human exploration, NASA began developing a small space station or “proving ground” for placement in cislunar orbit.