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As a key component of in-vehicle intelligent voice technology, speech enhancement can extract clean speech signals contaminated by environmental noise to improve the perceptual quality and intelligibility of speech. It has extensive applications in the field of intelligent car cabins. Although some end-to-end speech enhancement methods based on time domain have been proposed, there is often limited consideration given to designing model architectures based on the characteristics of the speech signal. In this paper, we propose a new U-Net based speech enhancement framework that utilizes the temporal correlation of speech signals to reconstruct higher-quality and more intelligible clean speech.

The new lightweight DA-6 Automotive Air Conditioning Compressor and Clutch Assembly is the lightest weight, most versatile 164 cc displacement compressor available today. It was designed and developed by General Motors which has produced over 72,000,000 compressors beginning with a 26.3 Kg rotary in 1953. In 1961, the 15.1 Kg six cylinder axial design was introduced and still remains a standard for the industry. A lighter weight 8.1 Kg radial four started production in 1974 and in 1982 the lightweight 5.7 Kg DA-6 will be introduced.

To ensure a robust, reliable and durable product, predicting the useful life of aggregates at the concept stage is a very important aspect in the any product design. This requirement is very much necessary in today’s competitive environment, wherein the customer expectations are increasing and development time for reliable product is shrinking. Clutch is one of the important aggregate in an automobile having manual transmission. It acts like a fuse in the driveline system wherein its wear and tear cannot be avoidable. The performance of Clutch is correlated with its useful life. In this paper, a unique methodology is formulated for the prediction of beta life of clutch. Actual field data of over 3 to 4 years related with warranty claims, mode of failures, usage kilometers etc. has been collected on a typical utility vehicle platform which has been operating on roads of Indian subcontinent.

Modern electronic diesel engine governor programs contain a considerable number of parameters and control characteristics describing the engine behaviour under all operating conditions. Alterations of these parameters allow the adaptation of the engine properties. A portable programming computer was developed which gives the motor engineer a handy tool to change these parameters even white the engine is running and without the help of the governor's manufacturer. Additionally the programming computer provides functions for display of real-time data such as engine speed, accelerator pedal position, control rack position etc.

A new 4.0 liter V8 engine, 1UZ-FE, has been developed for the luxury sedan, LEXUS LS400. The engine has 4 camshafts and 32 valves, and weighs only 195 kg (430 lbs) having many light alloy components and carefully designed configurations. The appropriate engine displacement and high technology adopted throughout from design to manufacturing process enable the LS400 to run powerfully with excellent fuel economy and a pleasant sounds. It develops 250HP at 5600 rpm and 260ft-lbs of torque at 4400 rpm, and its fuel economy figure, well exceeds the EPA's tax charge level of 22.5mpg. These figures have been achieved through the newest technologies applied to every part of the design, such as: Well studied intake and exhaust systems, centrally located spark plug in the TOYOTA original four-valve combustion chamber, which has a narrow valve including angle, and low friction components like aluminum alloy valve lifters and well balanced moving parts.

This paper is a preliminary step in the direction of the definition of a radically new wing concept that has been conceived to maximize the lift even at low speeds. It is expected to equip new aerial vehicle concepts that aim to compete against helicopters and tilt rotors. They aim achieving very good performance at very low speed (5 to 30 m/s) by mean of an innovative concept of morphing ducted-fan propelled wing that has been designed to maximize the lift force. This paper presents an effective bibliographic analysis of the problem that is a preliminary necessary step in the direction of the preliminary design of the wing. A preliminary CFD evaluation allows demonstrating that the claimed results are in line with the initial expectations. According to the CFD, results it has been produced a preliminary energetic evaluation of the vehicle in a flying car configuration by EMIPS method.

The performance of five positive k-factor injector tips has been assessed in this work by analyzing a comprehensive set of injected mass, momentum, and spray measurements. Using high speed shadowgraphs of the injected diesel plumes, the sensitivities of measured vapor penetration and dispersion to injection pressure (100-250MPa) and ambient density (20-52 kg/m3) have been compared with the Naber-Siebers empirical spray model to gain understanding of second order effects of orifice diameter. Varying in size from 137 to 353μm, the orifice diameters and corresponding injector tips are appropriate for a relatively wide range of engine cylinder sizes (from 0.5 to 5L). In this regime, decreasing the orifice exit diameter was found to reduce spray penetration sensitivity to differential injection pressure. The cone angle and k-factored orifice exit diameter were found to be uncorrelated.

Design optimization methods are commonly used for weight reduction subjecting to multiple constraints in automotive industry. One of the major challenges remained is to deal with a large number of design variables for large-scale design optimization problems effectively. In this paper, a new approach based on fuzzy rough set is proposed to address this issue. The concept of rough set theory is to deal with redundant information and seek for a reduced design variable set. The proposed method first exploits fuzzy rough set to screen out the insignificant or redundant design variables with regard to the output functions, then uses the reduced design variable set for design optimization. A vehicle body structure is used to demonstrate the effectiveness of the proposed method and compare with a traditional weighted sensitivity based main effect approach.

This paper discusses a new high efficiency variable speed permanent magnet (PM) d-c electric motor designed for initial use in windshield wiper assemblies on 1967 passenger cars. It traces the development from the basic two-speed, three-brush PM motor to the more sophisticated variable speed unit. Laboratory test data are used to compare performance of a variable speed wire-wound design and a two-speed PM motor with the new variable speed PM unit. Evolution of the needed circuitry is discussed and illustrated. The importance of using a diode in the circuit is stressed as the key to success in the high efficiency variable speed PM development.

Variable-valve-actuation mechanism is considered to be one of the most suitable solutions to realize the compatibility between higher power output and performances in the practical speed range. A new variable-valve-actuation mechanism named “Shuttle Cam” was designed and studied. In this mechanism which was applied to a conventional motorcycle engine with rocker arms and gear-train-driven valve system, the cam gears move along the idler gear. And cam shafts simultaneously slide along the rocker-arm slipper surfaces which are concentric with the idler gear. Consequently valve lift varies continuously in accordance with the alteration in the rocker-arm lever ratio and the cam phasing changes simultaneously in accordance with the cam gear rotation. Result of the experiments has confirmed that the mechanism functions accurately even at high speeds up to 10,000 rpm and some improvements were achieved in power output, fuel consumption, idling quality, and exhaust-noise level.

A new vibration diagnosis method for diesel engine based on the Neural Network and Wavelet Analysis is proposed in this paper. It is an on-line prognostics and diagnosis technique by picking-up the frequency characters of the vibration signals on the cylinder head or body of diesel engine. The experiments were carried out on the 295 Diesel Engine and a large number of training and testing samples were acquired. The Wavelet Noise Reduction is used to reduce the disturbance of background noises and the Wavelet Decomposition is applied to obtain the relevant characteristic vectors. Then a Radial Basis Function neural network is built. Using the experiment data to train it. After that, the neural network can be used to classify the faults of diesel engine according to the measured vibration signals on the cylinder head. The simulation and experiment results demonstrate that this method can efficiently diagnose and classify the faults.

In the last several years, technical advances and regulatory pressures have motivated the need for flexible, simple, and performance-based solutions for conducting development assurance in support of a system safety assessment process. Additionally, the affected design space for commercial vehicles has been growing beyond the conventional regulations for airplanes, rotorcraft, engines, and propellers, addressed by current Aerospace Recommended Practices (ARPs). This space is beginning to include commercial technologies such as unmanned aerial systems, multi-stage spacecraft systems, and road-able aircraft. These developing areas are each accompanied with their own development assurance expectations in support of their safety criteria. Concurrently, the industry and regulators are working to simplify guidance for system safety and development assurance, which has been foundational in the aircraft industry for decades.

In this study the influence of various blends biodiesel on steady state exhaust emissions was determined using, in terms of technology, two different cars. A first series of tests were conducted in Greece and a second series of tests were conducted in Belgium. An old technology Ford Escort 1986 model, 1.6L, 4 cylinders with indirect injection system engine was used on a chassis dynamometer in Greece [1] and a Volvo V70 2.5L, 2003 model with a modern engine fitted on was tested in Belgium [2]. The Greek test car was not equipped with an engine Electronic Control Unit (ECU) and run on the dynamometer with full load on three different gear settings (second gear, third gear and fourth gear). The Belgian car was a modern Volvo V70 2.5L Turbo Diesel. Seven fuels were used in both cases, a high sulfur diesel, more than 300 ppm, in Greece, and blends of 10%, 20%, 30%, 40% and 50% by weight biodiesel in neat diesel or (B10), (B20), (B30), (B40), (B50) and (B100) respectively.

Transient automotive sounds often possess a complex internal structure resulting from one or more impacts combined with mechanical and acoustic cavity resonances. This structure can be revealed by a new technique for obtaining translation-invariant scalograms from orthogonal discrete wavelet transforms. These scalograms are particularly well suited to the visualization of complex sound transients which span a wide dynamic range in time (ms to s) and frequency (∼100Hz to ∼10kHz). As examples, scalograms and spectrograms of door latch closing events from a variety of automotive platforms are discussed and compared in light of the subjective rankings of the sounds.

With the increasing emphasis on Systems Engineering, there is a need to ensure that Electrical/Electronic (E/E) Systems Endurance Testing of vehicles, in a real world environment, prior to Production Launch, is performed in a manner and at a technological level that is commensurate with the high level of electronics and computers in contemporary vehicles. Additionally, validating the design and performance of individual standalone electronic systems and modules “on the bench” does not guarantee that all the permutations and combinations of real-world hardware, software, and driving conditions are taken into account. Traditional Proving Ground (PG) vehicle testing focuses mainly on powertrain durability testing, with only a simple checklist being used by the PG drivers as a reminder to cycle some of the electrical components such as the power window switches, turn signals, etc.

A new method to determine steady state tire characteristics is presented, in order to be used in vehicle dynamic simulations. The test rig input variables wheel load, slip angle, longitudinal slip, linear speed and tire inflation pressure are specified in such a way, that high strain to the tire will occur only for short periods. Input variables, responsible for tire wear (longitudinal slip and slip angle), were controlled by stochastic functions. By that means a symmetrical tire wear is produced which is essential for good quality of the measured data. In order to avoid the necessity of measuring all multi-dimensional characteristics, a tire-model is used for further data processing. It's parameters are adjusted to measured data with the help of an optimization-strategy. By that way test rig measuring time can be shortend significantly, as compared with previous methods. The new method allows a fast and high quality determination of tire characteristics.

Failures in automobile cable harnesses account for at least 30%of all automotive electronics failures, and contribute over 50% of the electronic control modules (ECUs) returned to the factory and marked “no trouble found.” This paper discusses the use of Wave Signature Analysis (WSA) and Time Domain Reflectometry (TDR)1 to detect actual and potential failures in cable harnesses. “Failures” here include not only the normal faults of the harness, connectors, sensors, and actuators, but also the loading effects and variability of wires that induce failures in ECUs. The technique can be employed throughout the cycle of harness life -- design and characterization, production testing, and diagnosis in the service bay. Solving these interconnect problems in the automobile will result in faster prototype development, better assembly line testing, and more accurate service diagnosis. The technology can either be employed as a stand-alone system or incorporated directly into the ECU module.

Wear testing methods are the key factor in the development of new materials and surface treatment processes for valve seat insert applications. A new wear tester was developed to simulate the wear process of valve seat/insert based on the analysis of valve seat insert wear mechanisms. Normal contact and sliding motions were generated by two motors to synthesize the complex actions of the valve on the insert in an internal combustion engine. Initial wear test at 260°C (500°F) indicates there is a good agreement with the field engine test results of intake applications. Because of the short testing time and simple geometry shape of the specimens, it is possible to conduct massive wear tests for new valve seat insert alloy developments. This new tester also provides a useful tool to the study of wear mechanisms under complex mechanical actions.

In response to Automotive OEM's need for higher quality in plastics used in interior trim applications, Monsanto has developed a color stable material to meet stricter UV stability requirements. This material, an ASA polymer, has properties similar to ABS and excellent melt-flow which allows molding of large and complex parts. The product can be readily colored and has outstanding color stability as demonstrated by accelerated UV as well as actual outdoor testing.

For a light duty truck, the frame is a structural system and it must go through a series of proving ground events to meet fatigue performance requirement. Nowadays, in order to meet stringent CAFE standards, auto manufacturers are seeking to keep the vehicle weight as light as possible. The weight reduction on the frame is a challenging task as it still needs to maintain the strength, safety, and durability fatigue performance. CAE fatigue simulation is widely used in frame design before the physical proving ground tests are performed. A typical frame durability fatigue analysis includes both the base metal fatigue analysis and seam weld fatigue analysis. Usually the gauges of the frame components are dictated by the seam weld fatigue performance so opportunities for weight reduction may exist in areas away from the welds. One method to reduce frame weight is to cut lightening holes in the areas that have little impact on the frame fatigue performance.