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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.

THIS STANDARD ESTABLISHES THE DIMENSIONAL AND VISUAL QUALITY REQUIREMENTS, LOT REQUIREMENTS, AND PACKAGING AND LABELING REQUIREMENTS FOR D-RINGS MOLDED FROM MIL-P-25732 ACRYLONITRILE BUTADIENE (NBR) RUBBER. IT SHALL BE USED FOR PROCUREMENT PURPOSES.

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 specification covers a zinc alloy in the form of die castings.

(From Standards Proposal No. 2358, formulated under the cognizance of the EIA Quality and Reliability Engineering (QRE) Committee.)

Conventional attribute sampling plans based upon nonzero acceptance numbers are no longer desirable. In addition, emphasis is now placed on the quality level that is received by the customer. This relates directly to the Lot Tolerance Percent Defective (LTPD) value or the Limiting Quality Protection of MIL-STD-105. Measuring quality levels in percent nonconforming, although not incorrect, has been replaced with quality levels measured in parts per million (PPM). As a result, this standard addresses the need for sampling plans that can augment MIL-STD-105, are based upon a zero acceptance number, and address quality (nonconformance) levels in the parts per million range. This document does not address minor nonconformances, which are defined as nonconformances that are not likely to reduce materially the usability of the unit of product for its intended purpose.

This specification covers a zinc alloy in the form of die castings.

The YF-23A Advanced Tactical prototype Fighter was a revolutionary statically unstable, twin engine aircraft that cruised at supersonic speeds without afterburner and was designed to out maneuver opponents at subsonic and supersonic speeds. Combining these capabilities into a chosen aircraft configuration demanded a flight control hydraulic system of unprecedented power and performance. Increased system reliability, and reduced maintenance also presented a challenging system design. The YF-23A's unique flight and maneuvering envelope required high surface rates and large actuator excursions at low flight speeds, as well as power to generate increased hinge moments at supersonic speeds. To achieve these specifications, Northrop developed a hydraulic system that utilized flow conservation and prioritization techniques. The hydraulic system configuration was maintained by using hydrologic, as well as electronic control.

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.

The first flight of a delta wing aircraft took place in the United States at the Muroc AFB Flight Test Center on 18 September 1948. The aircraft, Convair No. 7002, Air Force S/N 46-682 and designated the XF-92A was piloted by Convair's Manager of Flight Research, E.D. “Sam” Shannon. The author witnessed this historic flight as a Flight Test Engineer on the project. Studies and wind tunnel tests for a supersonic interceptor were conducted at the Vultee Division of Consolidated Vultee Aircraft Corporation (Convair) in 1945. These studies led to the selection of the 60° delta wing plan form. This paper reviews the major differences between the thin wing XF-92A and the thick wing DM-1 glider (never flown) designed by Alexander M. Lippisch in Germany at the close of World War II. The XF-92A used a fully hydraulic irreversible control system for its elevons and rudder. The only airplanes up to this time with fully hydraulic controls were the Northrop XB-35 and the YB-49 flying wings.

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.

AS23190 is a procurement specification that covers a series of plastic and metal components and devices used for the tying, positioning, and supporting cable, cable assemblies, wire, and wire bundles in electrical, electronic and communication equipment, and in interconnection systems.

AS23190 is a procurement specification that covers a series of plastic and metal components and devices used for the tying, positioning, and supporting cable, cable assemblies, wire, and wire bundles in electrical, electronic, and communication equipment, and in interconnection systems.

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 covers one type of bronze in the form of round wire 0.500 inch (12.70 mm) and under in nominal diameter (see 8.5).

This specification covers both insulated and uninsulated solid conductor wire, designed for solderless wrap connections in electrical and electronic devices and equipment. The terminations of the wire are intended to be made with hand or automatic tools which wrap the wire, under tension, around terminal pins (commonly called wrapposts) to form solderless wrapped connections.

This specification covers both insulated and uninsulated solid conductor wire, designed for solderless wrap connections in electrical and electronic devices and equipment. The terminations of the wire are intended to be made with hand or automatic tools which wrap the wire, under tension, around terminal pins (commonly called wrapposts) to form solderless wrapped connections.