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The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

MONOGAL is a coated steel developped to improve the corrosion resistance of exposed automotive body applications. Its process os based on the brittleness of the η zinc coating in a range of temperatures below the melting point of the zinc. MONOGAL is produced on a hot dip galvanizing line; at the exit of the pot the free zinc is brushed off the light side of the differentially coated sheet. Side 1 of MONOGAL presents a very thin and continuous layer of iron-zinc diffusion alloy with no free zinc. Side 2 is a standard G90 or G60 zinc coating. The iron-zinc alloy layer has excellent anti-galling properties which improve the formability of MONOGAL over two side hot dip galvanized steel with the same r value. MONOGAL also shows good weldability, paintability and corrosion resistance.

To prevent engine scuffing in the field a new laboratory test called the Hot Tube Test has been established in order to evaluate the high temperature stability of diesel engine oils. In a strip mining application field test using 47 bulldozers powered by the same engine type, half of the engines suffered from piston scuffing failures when operated on a variety of commercially available API CD quality SAE 30 Grade engine oils. All the field test oils have been investigated using the Hot Tube Test, and an analysis of the results indicates that it would be possible to accurately predict scuffing failures by this test method. Furthermore, the reliability of this analysis has been verified by bench engine testing on reference oils. The reasons why the Hot Tube Test predicts the anti-scuffing performance of engine oils are discussed.

Carbon and rephosphorized pre-strained sheet steels for cold drawing forming operations were studied and the tensile, high cycle fatigue and fatigue crack propagation properties were determined. The fatigue limit was found to be higher for 20% than for 1% pre-strained condition. Threshold stress intensity factors (▵Ků) of 5.29 MPa. m1/2 for rephosphorized steel and 7.07 MPa. m1/2 for carbon steel. Critical crack lenghts were calculated by ▵Ků and fatigue limit data using the Lukas-Klesnil short-crack criterion. Through fractographic analysis it was possible to determine the general behavior of tested materials near threshold.

Driver state monitoring is a crucial technology for enhancing road safety and preventing human error-caused accidents in the era of autonomous vehicles. This paper presents CogniSafe, a comprehensive driver monitoring system that uses deep learning and computer vision methods to detect various types of driver distractions and fatigue. CogniSafe consists of four modules: Driver anomaly detection and classification: A novel two-phase network that proposes and recognizes driver anomalies, such as texting, drinking, and adjusting radios, using multimodal and multiview input. Gaze estimation: A video-based neural network that jointly learns head pose and gaze dynamics, achieving robust and efficient gaze estimation across different head poses. Eye state analysis: A multi-tasking CNN that encodes features from both eye and mouth regions, predicting the percentage of eye closure (PERCLOS) and the frequency of mouth opening (FOM).

“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.

The objective of the development of the aerodynamic drag predictive tool CDaero was for use as a module for the Automobile Design Support System (AutoDSS). CDaero is an empirically based drag coefficient predictive tool based initially on the MIRA (Motor Industry Research Association) algorithm. The development philosophy was to be able to predict the aerodynamic drag coefficient of an automobile with knowledge of the features of the surface geometry control curves. These are the curves that control the 3-dimensional geometry as seen in the profile, plan and front and rear views. CDaero has been developed in a computing environment using the equation solver TKSolver™. Fifty-one input feature values are first determined from the automobile geometry and then entered into the program. CDaero models the drag coefficient with thirteen different components covering the basic body, as well as additional components such as the wheels, mud flaps, etc.

In today’s Automotive world, there is NO need to advocate “Light weighting”. Government policies for carbon footprint reduction combined with high safety standards are driving OEMs to adopt advanced manufacturing technologies. Steel hot forming is selected as most preferred way to reduce weight as it is easy to adopt and commercially known. It had many advantages compare to conventional cold stamping of standard and high tensile steel. The process consists of heating blank to nearly 1000 °C and quenching it in tool to for martensitic structure. Higher strength up to 2000 MPa can be achieved by this process. There are many examples where part weight is reduced by 15 to 20 % by this method. But Steel hot forming has limitation as specific density of steel is still high. Thus, there is limitation to its weight reduction capability. For further reduction, OEMs have started exploring Aluminium hot forming.

With the advent of low evaporative emission requirements there has been the rapid adoption of multilayer extrusion technology into the production of Fuel and Vapour tubing used on Fuel systems on automobiles. Multilayer extrusion technology enables a manufacturer of Fuel and Vapour tubing to simultaneously co-extrude dissimilar thermoplastic materials in tubular form. This allows the manufacturer to combine expensive and brittle high performance evaporative emission ‘barrier’ polymers with lower cost engineering polymers. However, it is a well-known characteristic of these multilayer tube constructions that the joints between them and connector ‘barbs’ have lower joint integrity. Joint integrity is most often quantified by ‘Pull-off’ and leakage tests. Recent developments in LEV-II requirements for 2004 and beyond indicate that joint integrity will become a focus area for study and improvement.

3-D Flow separations such as those that occur on the rear end of a vehicle have an impact on wall pressure distribution, hence on aerodynamic forces. The identification of these phenomena can be made through the analysis of skin friction patterns, which consist of the “footprints” of flow separations. These can be determined from qualitative and quantitative data obtained from near-wall PIV measurements. The wake flow of different configurations of a simplified 1/4 scale car model are analyzed. The influence of the slant angle and the Reynolds number on 3-D separated flow patterns and their induced pressure distribution is addressed, based on near-wall PIV, standard PIV and wall pressure measurements. This enables to understand how a topological change (the size or shape of a separation pattern) modifies the associated pressure distribution (therefore the drag coefficient). Finally, insights into instantaneous topology identification are presented.

The Swedish Biomimetics 3000's μMist® platform technology has been used to develop a radically new injection system. This prototype system, developed and characterized with support from Lotus, as part of Swedish Biomimetics 3000®'s V₂IO innovation accelerating model, delivers improved combustion efficiency through achieving exceptionally small droplets, at fuel rail pressures far less than conventional GDI systems and as low as PFI systems. The system gives the opportunity to prepare and deliver all of the fuel load for the engine while the intake valves are open and after the exhaust valves have closed, thereby offering the potential to use advanced charge scavenging techniques in PFI engines which have hitherto been restricted to direct-injection engines, and at a lower system cost than a GDI injection system.

SIMULTANEOUS RECORDINGS of cylinder pressure, audible sound, and crankshaft motion have shown that rumble is a noise associated with bending vibrations of the crankshaft. The vibrations are caused by abnormally high rates of pressure rise near the top dead center piston position. In this study the high rates of pressure rise were obtained by inducting deposits into the the engine. Thud is a torsional vibration of the crankshaft, similar in sound to rumble but resulting from much earlier occurrence of the maximum rates of pressure rise. Rumble vibrations consisted of a fundamental frequency of 600 cps and higher harmonics in the 11/1 compression ratio V-8 laboratory engine used in the investigation. The audible noise of rumble was predominantly composed of the second harmonic or about 1200 cps.

THE DEVELOPMENT of new polymers offering properties and new combinations of desirable characteristics, coupled with advances in manufacturing techniques, has expanded the plastics horizon. This paper describes some of these new materials and a few of their many possible applications in the automotive industry. The author emphasizes that greater use of plastics in the automotive field depends to a great degree on the imagination and ability applied in creating new products. Design features most overcome the fundamental limitations of the new materials. The basic weaknesses of plastics are listed. Production techniques will affect the future expansion of the industry. Three methods show particular promise: blow molding, fluidized polymer deposition, and potting compounds.*

STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*

NEW WELDING processes are dropping costs while providing improvements in weld quality. This paper describes some of the more promising new developments in pressure and fusion welding and brazing. Included in the discussion are ultrasonic, high frequency resistance, foil seam, magnetic force, percussion, friction, and thermopressure welding and diffusion bonding. The description of adhesive bonding includes the development of glass or ceramic materials as structural adhesives.*

This paper deals with the Coupled thermo mechanical analysis of a cylinder head, cylinder block and crank case with the liner of an uprated engine. The existing engine develops 780 hp output with mechanical driven supercharger and the engine is uprated to 1000 hp by replacing the supercharger with a turbocharger and new Fuel injection equipment. For uprating any engine, the piston and cylinder head are the most vulnerable members due to increased mechanical and thermal loadings. Mechanical loading is due to the gas pressure in the gas chamber and its magnitude can be judged in terms of peak pressure. Thermal loading is due to temperature and the heat transfer conditions in the piston surface, cylinder liner and the cylinder head. The relative importance of the various loads applied on the head and cylinder block in operation are assessed and a method of predicting their influence on the structural integrity of the components described.

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 permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.