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Distinctly different fire hazards exist within the engine compartment of a transit vehicle and various detection methodologies may be employed to detect fire events arising from these hazards. The engine compartment presents a particularly challenging environment and it is important to select the correct methodology to ensure timely detection response in the early stages of the development of a fire whilst minimizing nuisance alarms. The choice of the correct detection methodology for a specific fire hazard is therefore determined by the suitability of the methodology for the detection of the anticipated fire event within the environment in which it is required to operate. This paper presents experimental data to demonstrate the variation in the response times of different detection methodologies in the presence of common fire events in the form of simulated flaming fuel fires and a simulated electrical fault in the form of an overheated electrical cable.

Intermittent wiring faults are among the most frustrating, time consuming, and expensive problems to diagnose in electrical systems. These sporadic problems occur when wires are wet, vibrating, under pressure, or when the system is in a particular configuration during use. Then when the system is stable and/or powered down, the problems disappear. The best and often the only time to locate these faults is while the faulty wiring is live and in operation. This paper will describe new technology for locating intermittent faults on live wiring systems without interfering with their operation. Spread spectrum time domain reflectometry (SSTDR) has been developed for locating these intermittent faults on live aircraft wires. A pseudo noise (PN) code is injected on the wire, well below the noise margin of the system. The PN code can be self-correlated to give the characteristics of the wiring system - its branches, loads, sources, etc.

As electrical systems on-board commercial and military aircraft grow in complexity they must also be designed for enhanced safety and functionality. Maintenance and repair become more complex, troublesome and expensive as these systems evolve. Arcing faults occur as a result of chafing and cracking of insulation, dielectric breakdown, and looseness at terminal connections. Once arcing is initiated, damage may propagate to other conductors in the wire bundle. The discharge of arcing energy results in insulation damage, smoke events, the loss of adjacent wires in a wire bundle, and ignition of flammable materials and vapors. Such conditions have been estimated to result in approximately one unscheduled landing during an average day of air traffic worldwide, and are the primary suspects in a number of catastrophic events. Arc Fault Circuit Interrupting (AFCI) technology has been proposed as a means to improve aircraft wiring system safety.

The chemical storage battery is currently the primary choice of automotive powertrain designers for hybrid-electric vehicles. This design suffers from complexity, manufacturing, cost, durability, poor performance predictability and other problems. Additionally, the trend in hybrid powertrain design is to move from high energy density to high power density. A proposed alternative to chemical batteries for some hybrid vehicle applications is an electro-mechanical battery (EMB) that combines an electric machine with hydro-pneumatics to provide energy capture, storage, and propulsion assistance. An initial multi-domain physical system model of an EMB-based hybrid powertrain has been developed in the Simulink environment to show the behavior of the EMB design in a midsize hybrid passenger vehicle application.

Accurate measurements of productivity and quality are essential for balancing workload, creating predictable schedules and budgets, and controlling quality. Traditional software development processes include well-established methods for measuring productivity and quality. These include Lines of Code (LOC). With the introduction of Model-Based Design, organizations require a different measure of the software development process.

Modern automotive engine design is making the measurement of engine speed increasingly difficult, due to problems with access for the sensors and, hence, forms the motivation for this investigation. Some manufacturers provide a dedicated pin/socket for engine speed, but this is clearly vehicle specific and may not always be accessible. A novel method is described for the measurement of the speed of a reciprocating internal combustion engine, based on the analysis of the vibration of the engine block using an accelerometer. The Power Spectral Density (PSD) derived from the accelerometer signal contains a dominant peak of which engine speed is a multiple, and it is possible to track this peak over the engine speed range. Whilst initially developed for diesel engine application, the range of application has been extended to petrol engines, and hence the device can be truly described as a universal tachometer.

The present performance capabilities of liquid crystal displays relative to automotive requirements is reviewed. Fundamental material limitations to LCD performance will be discussed. Operating characteristics that may be anticipated in the next two to five years, in regards to such parameters as operating voltage, operating and storage temperatures, humidity resistance, response time, viewing characteristics, color and display styling will be treated. In addition, examples of the use of LCDs for portrayal of analog and vectorgraphic information will be presented.