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A program was developed that provides a user friendly interface for developing and testing shift tables in a powershift transmission. This program is Windows based and runs on an IBM compatible P.C. When coupled with a suitable controller, transmission designers have a useful tool for the development of transmission shift timing. The system is designed to be used in an engine test cell or for actual vehicle tests. This allows the vehicle operator to call up and edit shifts on a P.C. screen and then drive the vehicle using the new shifts. This allows the operator to evaluate results of real time shifts immediately.

Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.

Powertrain electrification is becoming increasingly common in the transportation sector to address the challenges of global warming and deteriorating air quality. This paper introduces a novel “Build Your Hybrid” approach to experience and test various hybrid powertrain concepts. This approach is applied to the light commercial vehicles (LCV) segment due to the attractive combination of a Diesel engine and a partly electrified powertrain. For this purpose, a demonstrator vehicle has been set up with a flexible P02 hybrid topology and a prototype Hybrid Control Unit (HCU). Based on user input, the HCU software modifies the control functions and simulation models to emulate different sub-topologies and levels of hybridization in the demonstrator vehicle. Three powertrain concepts are considered for LCVs: HV P2, 48V P2 and 48V P0 hybrid. Dedicated hybrid control strategies are developed to take full advantage of the synergies of the electrical system and reduce CO2 and NOx emissions.

This Life Support Laboratory consists of a simulator of the spacecraft called Nautilus, which houses Air Revitalization Subsystem, Atmospheric Control and Supply, and Fire Detection and Suppression in the Equipment Area. There are supporting facilities including a Human Metabolic Simulator, simulated Low and Moderate Temperature Coolant Loop, chemical analysis bench, purified water supply, vacuum and gas supplies. These facilities are scheduled to be completed and start to operate for demonstration purposes by March 2005. There are an ARES Ground Model (AGM) and a Trace Contaminant Control Assembly in the ARS. The latter will be integrated with the AGM and a Condensing Heat Exchanger. The unit of AGM is being engineered, built, and will be delivered in early 2005 by EADS Space Division. These assemblies will be operated for sensitivity analysis, integration and optimization studies. The main goal is the achievement for optimal recovery of oxygen.

SOME POSSIBILITIES for shortening the field length requirements of present-day jet aircraft are: Install leading-edge, high-lift devices which are retrofitable to present-day aircraft. Retrofit — or purchase new — aircraft powered by turbofan engines. These have an inherently higher take-off thrust to cruise thrust ratio than the jets, which vastly improves the take-off acceleration. Use boundary-layer control actuated by turbine discharge gas for immediate consideration in new aircraft engines. Use direct-lift jet engines. These will improve the block speed characteristics of the aircraft and also give vertical take-off and landing capabilities. This paper discusses the advantages of each of these possibilities. The author also describes the problem of airport location within a city, and its effect of total travel time.*

THE FIRST YEAR of jet airline operation has brought many problems — and satisfactions — to the industry. Here the author discusses some of the more serious problems: 1. Scheduling. American Airlines used the “Monte Carlo” method to calculate payloads and flight times. 2. Baggage handling. Almost nothing annoys a passenger more than long waits for baggage at the end of a flight. One approach to the problem is the baggage expediter system. 3. Mechanical shutdowns. 4. Runway length. 5. Noise. Noise suppressors have not been effective enough, from the standpoint of communities surroundings airports. Development of the turbofan engine offers some hope in this area.*

THE optimum mode of control for an aircraft engine is dependent on both the configuration of the engine and its application. Each engine application requires several detail modes of control, one for each definable regime of operation of the engine. Discussions of control requirements can be simplified by classifying these regimes by objectives: physical limiting, thrust, and transient control. The turbojet engine is the basis for the discussion in this paper. Acceptable modes of control can often be selected by inspection of the engine and its application. Selection of an “optimum” control mode requires investigation of the operation of the engine and weapons system at every stage of its use. The selection of a “mode” of control requires a compromise between performance and other design factors. The need for simplicity and accuracy must be balanced against the stability requirements. The availability and flexibility of control components may limit the modes of control considered.

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.

The scope is determine if an 'Electronic Authorized Release Certificate' is viable and what is needed to make it viable.

THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.

SUBSTANTIAL POWER is necessary to start the modern jet engine. Thus, starting equipment has become a major concern of air transport operators. This paper discusses the equipment used with self-contained starting systems. The authors discuss and evaluate a variety of self-contained systems: combustor, fuel-air combustion, cartridge, liquid propellant, hydraulic supported by auxiliary power units, and electric supported by APU. Possible future systems are: self-breathing systems, oxygen combustors, and liquid-oxygen-water-fuel combustors. It is emphasized that the choice of a starting system for a particular aircraft will depend on aircraft characteristics and the aircraft's intended use.*

GREATER ease of servicing is one of the ultimate goals in the development of dry-type air cleaners. The authors acknowledge, however, that the oil-bath cleaner is a rugged proved component that has done a good job for the farmers who serviced it properly. This paper describes studies made in Illinois of oil-bath and dry air cleaners in field service. At the same fuel/air ratios, the maximum horsepower of a test engine was greater with the dry-type filter than with the oil-bath cleaner. It was found that with AC fine dust and steady airflow, the oil-bath cleaners had significantly lower efficiencies than the dry-type filter. At less than rated airflow the efficiency of the oil-bath cleaner decreased while that of the dry filter remained high.

To enable the tests required for development work to be performed with maximum efficiency, the Zwick Roell Group (ZwickRoell) – a global supplier of materials testing machines based out of Ulm, Germany – developed a materials testing machine that can be equipped with both a temperature chamber and a high-temperature furnace.

The likelihood of transmission of potential disease agents between animals and man during spaceflight is a real concern. Development of disease exclusion lists for animals and refinement of animal containment units have been the principal means of providing protection to the crew members. Awareness of potential latent infections and a judicious use of the higher risk category of animals such as wild-caught nonhuman primates provides another level of protection. Use of high efficiency filters, gasketing, and differential air pressures have all enabled increasing levels of safety through containment of potential aerosol escape from animal habitats.

This specification covers the requirements for producing a zinc phosphate coating on ferrous alloys and the properties of the coating.

Future space exploration missions will require a lightweight spacesuit that expends no consumables. This paper describes the design and performance of a prototype heat rejection system that weighs less than current systems and vents zero water. The system uses regenerable LiCl/water absorption cooling. Absorption cooling boosts the heat absorbed from the crew member to a high temperature for rejection to space from a compact, non-venting radiator. The system is regenerated by heating to 100°C for two hours. The system provides refrigeration at 17°C and rejects heat at temperatures greater than 50°C. The overall cooling capacity is over 100 W-hr/kg.

The commercial aviation currently accounts for roughly 2.5 % of the global CO2 emissions and around 3.5% of world warming emissions, taking into account non CO2 effects on the climate. Its has grown faster in recent decades than the other transport modes (road, rail or shipping), with an average rate of 2.3%/year from 1990 to 2019, prior to the pandemic. Moreover, its share of Greenhouse (GHG) emissions is supposed to grow, with the increasing demand scenario of air trips worldwide. This scenario might threaten the decarbonization targets assumed by the aviation industry, in line with the world efforts to minimize the climate effects caused by the carbon emissions. In this context, hydrogen is set as a promising alternative to the traditional jet fuel, due to its zero carbon emissions.