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This paper gives an overview of the electronic motor management system DIGIFANT in the new Volkswagen Corrado with an 1.8 1 G60 super-charged engine with charge air cooling (1)*, which has been in production since summer 1988. The individual functions of the control software are described and explained in Detail. The system contains mixture control with lambda closed loop, automatic idle stabilization, feedback control of the charge air pressure and spark advance angle control with knock control. There is also an on-board diagnostic system.

Future driver assistance systems will not only monitor the current traffic situation, but actively assist the driver in emergencies. Autonomous intervention in vehicle dynamics will increasingly help keep the vehicle under control, even in difficult operating situations. A rapid and intelligent braking system is one of the foundations for advancing the next generation of driver assistance systems. Siemens VDO sees its electronic wedge brake (EWB) brake-by-wire technology as the answer to future vehicle chassis safety, weight, reliability, and space requirements. In early 2005, Siemens VDO Automotive AG acquired the innovative company eStop to enter the automotive brake market with the EWB. The EWB is a self-reinforcing electromechanical wedge brake, which operates around the point of maximum self-reinforcement, in order to minimize actuation forces to levels that can be supported by 12V vehicle electrical systems.

Embedded systems cover a wide variety of devices and applications. Seemingly, each embedded system is different from other embedded systems. After all, the system controlling a microwave oven has virtually nothing in common with the system in a calculator, an airplane flight controller, or a car's engine controller. However, is there a way to look at embedded systems from a generic viewpoint? Put another way, are there parts of all embedded systems that are common whatever the purpose or function of the individual devices? What exactly do the microwave oven controller and a vehicle's engine controller have in common? The design of a “layers-type” model representing embedded systems development arose from asking just such questions. Starting with the background of the OSI Network Model, where all functions of network communications fit within one of seven layers, we began to ask if a similar structure could serve to describe embedded systems.

The largest sales year for passenger cars and light trucks in the last eight years was. 1985. The light truck share of the light duty vehicle market increased from 21.0 percent in 1978 to 27.9 percent in 1985. Light trucks, on average, are less efficient than passenger cars. As light trucks enlarged their share in an expanded market, the impact on overall fuel economy increases has been dampened. Several explanations have been given for the increased consumer purchases of light trucks: low cost for many models, the availability of 4-wheel drive, temporary import limits on Japanese auto imports and increased nameplate offerings. The light duty vehicle fuel economy gain of 5.7 MPG between 1978 and 1985 would have been 8.8 percent higher if there had not been any shift in share toward light trucks during that period.

This paper will discuss sensors used for ignition timing today and examine a new sensor based upon a technology proven in the automotive market. Hall effect vane sensors have been used for many years, however, to improve performance and reduce cost, a Hall effect probe sensor has been developed. Traditionally. Hall effect sensors have required that either a magnet or fabricated vane target be mounted on a rotating shaft in order to receive position information. The new probe sensor utilizes a specially designed integrated circuit to sense changes in magnetic flux densities created by the proximity of a metal target such as a geartooth. This sensor was designed with the automotive market specifically in mind. Included in this composition will be the benefits which can be derived from the incorporation of this type of sensor and how this represents the next level of advancement in ignition timing applications.

A detailed investigation of the emergency straight-path braking behaviour of a sample of 59 volunteer motorcycle riders with a wide range of riding experience and skill has been performed on the test track with the aid of a motorcycle instrumented to measure and record a number of variables related to the braking task. Analysis of the data revealed that the skilled riders applied larger front and rear brake-lever force inputs, had shorter reaction times, and were able to proportion their front and rear brake force inputs in the manner required for optimum utilization of the available tyre/road friction. By contrast, the braking behaviour of the less-skilled riders could lead to early “lock-up” of the rear wheel. This finding suggests that less proficient riders could brake a motorcycle more effectively if it was equipped with an integrated and/or anti-lock braking system.

Consider this recent data about the "speed'' of the information age: In a sixty-month window beginning in the year 1995, the number of cellular phone subscribers increased from 90 million to 330 million, the number of people on the internet went from about 5 million to just under 200 million, and not surprisingly the number of websites grew from a few thousands to 50 million. Now further consider that almost every cellular phone subscriber is also an automobile user, be it as a driver or a passenger. A fabric of mobility soon emerges --- one that is formed by the meshing of the strands of information mobility with those of personal mobility. In this paper we explore a "new frontier'' --- a "territory'' on this multidimensional fabric that is defined by the demands of seamless mobility. The typical daily cycle of events in our lives involve many different modalities and time-phases of mobility. We examine the rapidly increasing demands of seamless mobility in this context.

With growing concern over greenhouse gases there is increasing emphasis on reducing CO2 emissions. Despite engine efficiency improvements plus increased dieselisation of the fleet, increasing vehicle numbers results in increasing CO2 emissions. To reverse this trend the fuel source must be changed to renewable fuels which are CO2 neutral. A common route towards this goal is to substitute diesel fuel with esterified seed oils, collectively known as Fatty Acid Methyl Esters. However a fundamental change to the fuel chemistry produces new challenges in ensuring compatibility between fuel and engine performance/durability. This paper discusses the global situation and shows how fuel additives can overcome the challenges presented by the use of biodiesel.

The continued development of high-performance low-cost computing systems, the Miniframe, is having a significant impact on the scientific computing marketplace. The purpose of this paper is to describe the characteristics of the Miniframe describe the role of Miniframes in distributed computing compare the cost/performance of Miniframes with present mainframes address the inevitability of changes to the present computer organizational structure and consider the new burdens that will be imposed on engineering management.

The emissions performance of a fleet of five vehicles equipped with prototype 1975 catalyst emission control systems and run under field conditions for up to 125,000 miles (202,000 km) was evaluated. The vehicles were driven by non-expert drivers in California and Michigan for commuting and personal use and maintained in a manner similar to in-use vehicles. The average fleet emissions of hydrocarbons (HC) remained below the 1975 California emission standards appropriate for these vehicles for 80,000 miles (129,000 km), the average carbon monoxide (CO) emissions remained below the standard for 70,000 miles (113,000 km), and emissions of oxides of nitrogen (NOx) never exceeded the appropriate standards.

The LNT(Lean NOx Trap) system has been developed for NOx reduction to meet Tier2Bin5 by using 2.2ℓ-diesel engine which was recently introduced by Hyundai Kia Motor company. The compression ratio was adjusted to 15.5 and the trim size of the turbine was reduced to increase EGR rates. During the FTP75 mode test, the engine out NOx was reduced by about 30% compared to the standard engine. The rich mode combustion was developed for the wide operating range despite of the low compression ratio. It was accomplished by adjusting air and FIE system, mainly by increasing post2 injection quantity. The A/F (Air-to-Fuel) ratio was controlled by additional post2 injection quantity. The neutral transition between lean mode and rich mode combustion was completed. The noise and torque change could not be recognized by the drivers during the transition of combustion mode (lean-to-rich or rich-to-lean). The transition procedure was finished within about 1sec for the whole operating range.

Comparative exhaust emission tests were performed on Japanese light- and heavy-duty vehicles fuelled with a Fischer-Tropsch diesel derived from natural gas and two crude oil-derived reference diesels. Both vehicles were tested without and with an oxidation catalyst fitted to the engine. In the case of the light-duty vehicle a current Japanese specification diesel and a future specification low sulphur diesel were used as reference while in the case of the heavy-duty vehicle only the low sulphur diesel was used as reference. The emission tests were performed using the standard Japanese emission test cycle applicable to that vehicle type. In addition certain selected modes from a special test cycle representative of congested traffic patterns encountered in the Tokyo inner city environment were used for both the light- and heavy-duty vehicles. In general, Fischer-Tropsch diesel reduced all the regulated emissions compared to both crude derived diesels.

Engine experiments were carried out in order to investigate the mechanisms involved in connection with the emission of lubricant related polyaromatic hydrocarbons (PAH) from a D.I. diesel engine. In the experiments only the mechanisms related to pyrene emissions were investigated, since synthetic fuels and lubricants containing pyrene as the only aromatic compond were used. Particulate matter (PM) and the soluble organic fraction (SOF) of PM as well as PAH emissions were measured for different engine conditions at different levels of pyrene in the lubricant and the fuel. Possible mechanisms of PAH transportation from the lubricant to the exhaust gas are discussed based on the experimental results, as well as the importance of fuel and lubricant to SOF and PAH emissions.

Emissions of diesel engine have been received much more attention since the Volkswagen Emission Scandal. The Euro VI emission standard has already included cold start emissions in the legislative emission driving cycles which is one of the hardest part of emission control. High altitude performance is also considered in the latest regulations which will be stricter in the future. Heating the coolant is one of the most common method to improve the cold start performance. But researches focus on the emission of a diesel engine in different coolant temperature at high altitude which up to 4500m have not been seen. The present research investigated the effect of coolant temperature on performance and exhaust emissions (gaseous and particulate emissions) during the cold start of a diesel engine. A plateau simulation system controlled the inlet and exhaust pressure to create altitude environments from 0m to 4500m, and the coolant temperature was controlled from 20°C to 60°C.

As part of a cooperative development program, six diesel fuels (a reference and five blends containing oxygenates) were evaluated under four steady-state conditions using a prototype 1.26-L 3-cylinder four-valve common-rail DI diesel engine. All of the fuels contained low sulfur (mostly < 5 ppm by mass), and they were chosen to determine the impacts of oxygenate volatility, concentration, and chemical type (paraffinic or aromatic) on exhaust emissions - with particular emphasis on particulate emissions. In addition to HC, CO, NOx and PM emissions measurements, emissions of the volatile portion of the PM and particle size were determined. Relative to the very low sulfur reference fuel, the oxygenated fuels reduced PM and NOx under some operating conditions, but produced little effect on either HC or CO emissions. Aliphatic oxygenates at 6 wt. percent oxygen in the reference fuel reduced simulated FTP PM emissions by 15 - 27 %.

Progress in development of thermionic fuel elements (TFE) of thermionic nuclear reactor-converters having more than 3 W/cm2 specific electric capacity to the considerable extend is connected with the application of refractory crystal emitters on the base of tungsten and its alloys. The technology of all single crystal (110) oriented tungsten emitter envelopes was developed at the IPPE. The sample lot of the envelopes was manufactured and then investigated during laboratory and lifetime electrically heated tests. One of the promising direction of this technology progress is the employment of tungsten facetted coating having mainly (110) orientation. This report is development of [1,2,3]. In the report the investigation results of surface properties of emitter envelope facetted coating as well as results of lifetime tests of TEC with hexahedral geometry W(110) - W(110) electrode envelopes are discussed.

The Conductively Coupled Multi-Cell Thermionic Fuel Element combines the best aspects of the single cell and multi-cell TFE designs. The key element in this TFE design is the emitter tri-layer. The emitter tri-layer places strict requirements on material properties especially the insulator material. Emitter tri-layers composites consisting of scandium oxide and tungsten were fabricated and tested. Scandium oxide has met the requirements of thermal stability, mechanical strength and electrical resistance lifetime tests. Initial results on cesium plasma compatibility test indicate that scandium oxide will meet the chemical compatibility requirement.

THE AMERICAN public demands that, in safety, comfort, appearance, speed, acceleration and deceleration, motorcoaches shall compare favorably with the present-day automobile, according to the author. These demands have resulted in a substantial increase in weight that has required the use of much larger engines, and this has brought about a tremendous increase in fuel consumption. Since fuel costs represent a large percentage of the total cost of operation, the possibility of decreasing these expenditures is receiving considerable attention. In addition, and apart from the increase in fuel usage resulting, taxation is causing grave concern. The author describes the fuel issue as it now exists in the United States. Data are submitted showing the tax situation, costs and refining operations, the potential saving assuming the employment of the less volatile fuels, their possible method of employment, advantages, disadvantages and the like.

An experimentally derived map of the engine volumetric efficiency is usually employed to control the A/F ratio in a SI-ICE. In the case of a variable valve timing (VVT) engine, a different efficiency map must be considered at each camshaft position, as a consequence of the influence on the air flow exerted by the actual position of the intake/exhaust camshaft. In this paper, an attempt is reported to theoretically derive a correlation of the volumetric efficiency as a function of engine speed, manifold absolute pressure, and camshaft position. The correlation is not based on experimental data but on the results of a one-dimensional simulation model (1Dime code) developed at DIME. An extensive validation of the 1D model is preliminary reported in the first part of the paper. The procedure is developed with reference to a four-cylinder, SI engine, equipped with a phased intake and exhaust VVT device.