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For commercial-vehicle Original Equipment Manufacturers (OEMs), predictive maintenance has drawn attention for the benefits of money saving and increased road safety. Data-driven models have been widely explored and implemented as predictive maintenance solutions. However, the working scenarios for different commercial-vehicles vary a lot, which makes it difficult to build a universal model suitable for all the cases. In this paper, we propose a Recurrent Neural Adaptive Processes (RNAPs) network to adapt to different scenarios by modeling the uncertain at the same time. The ensemble network combines the traits of neural processes, recurrent neural network and meta learning together. Neural processes consider the context information to calculate the uncertainty and improve the prediction results. Meta-learning works well when dealing with few-shot multi-tasks learning, and recurrent networks are utilized as the encoder of the proposed model to process time-series data.

As engines become lighter and achieve higher output to meet carbon dioxide emissions targets, it becomes more challenging to design a crankshaft that is both lighter and capable of handling higher loads. Therefore, it is necessary to understand the characteristics of forces imposed on the crankshaft, and the mechanisms by which stresses are created in the crankshaft. This paper describes the characteristics of bending stresses measured on the rearmost crank pin fillet of a crankshaft. Two basic crankshaft resonant modes are described. Forward crankshaft whirl then has the effect of increasing the system natural frequencies by the stiffening effect, while reverse whirl reduces the system natural frequencies by the softening effect. The effect of whirl grows with increasing engine speed. This results in what appears to be four crankshaft natural frequencies rather than two. The four resonances appear at all non-zero engine speeds.

As a result of WNTE regulations and the introduction of close-coupled aftertreatment systems, exhaust purification at high temperatures in commercial vehicles has become increasingly important in recent years. In this report, we improve the prediction accuracy for NOx conversion at high temperatures in the kinetic model of conventional Cu-selective catalytic reduction (Cu-SCR). Reaction rate analysis indicated that the rate of NH3 oxidation was extremely low compared to the rate of standard SCR. We found that NOx concentration-dependent NH3 oxidations (termed NOx-assisted NH3 oxidations) were key to the rate of NH3 oxidation. The output of the improved Cu-SCR kinetic model was in agreed with experimental results obtained from the synthetic gas bench and engine dynamometer bench. We analyzed the contribution of each reaction to NH3 consumption during Cu-SCR. Under NH3 + NO + O2, standard SCR was dominant at low temperature.

The objective of this study was to develop a test method for heavy-duty HEVs using a hardware-in-the-loop simulator (HILS) to enhance the type-approval-test method. To achieve our objective, HILS systems for series and parallel HEVs were actually constructed to verify calculation accuracy. Comparison of calculated and measured data (vehicle speed, motor/generator power, rechargeable energy storage system power/voltage/current/state of charge, and fuel economy) revealed them to be in good agreement. Calculation error for fuel economy was less than 2%.

The sense of a human being is expressed in a word always with the sensuous evaluation to idling noise. However, due to the sense of the human being is very complicated basically and be including delicate elements, there is a limit to express it in a word. Also, idling noise might be giving a stress to our body, without feeling it. Then, several studies have been made on physiological information receive the response of a human being objectively, tried to evaluate the load of a body. Electrocardiogram (ECG) and respiratory curve were measured to examine the influence that the disclosure of idling noise exerts on the autonomic nervous system function in this study. Heart rate variability (HRV) was obtained from ECG and respiratory frequency was obtained from respiratory curve in the analysis. Seven subjects were adult males who were healthy hearing. We investigated the result with considering the differences by 4 kinds of noise and 2 kinds of sound pressure.

It is well known that a high-pressure fuel injection is effective for the reduction in particulates and smoke emissions. Exhaust gas recirculation (EGR) is effective for the reduction in NOX emission. In this study an experiment aiming to understand more comprehensive combustion under the condition of EGR and high-pressure fuel injection was carried out by using gas sampling method for the purpose of understanding what occurred inside the spray before and after combustion. The number of combustion cycles in this engine can be controlled in order to change EGR conditions by adjusting the residual gas concentration in the cylinder. Main results were: (1) Close to the nozzle tip, the sampling gas data showed little reaction which implies that combustion never occurs in this area during the injection period. (2) In the case of high-pressure fuel injection O2 concentration decreased faster and air dilution was more active and earlier.

The OH and soot in an unsteady flame, which was achieved in a rapid compression machine, were visualized simultaneously by the laser-induced fluorescence and laser-induced scattering techniques. The fuel mixture consisting of 90% paraffin hydrocarbon (reference fuel) and 10% polypropylene-glycol was used to reduce the optical attenuation caused by dense soot cloud. The simultaneous images of the fluorescence from OH and scattering from soot show that the soot and OH exist separately from each other in the leading portion of the spray flame, and the OH is formed earlier than the soot in the near field region of spray flame.

“ISUZU GIGA” series of new heavy duty commercial vehicles introduced in Japan in November 1994 are equipped with new V-type, naturally aspirated PE series engines. The PE series engines supersede PD series which has been well accepted in the markets domestic and abroad. The new series has been designed to meet Japan's new 1994 exhaust emission regulations while achieving high output power, low weight, good fuel economy, and high reliability. One outstanding feature of the PE engines is the use of dry liners which few other V engines have. This has made it possible to accommodate increase bore size and increase engine displacement by 14 % while maintaining the relatively short bore pitch of 146 mm. PE engine is in fact a high output engine with the smallest weight in class. The series includes V8, V10 and V12 engines ranging in output from 210 kW to 331 kW, the latter being Isuzu's most powerful engine. Six models differing in output power are available.

An investigation into the application of electronically controlled solenoid activated high pressure in-cylinder gasoline injection systems has been carried out in both conventional and novel four-valve four-stroke pent-roof chamber single-cylinder engines. Air motion requirements were studied and their effects on port design and layout were assessed. Alternative injector types, locations and spray characteristics were investigated. Transient and steady-state comparisons of the engines were made under both normal and cold running conditions. The outlook for the use of in-cylinder injection technology compatible with ULEV emissions requirements is discussed in the light of the results obtained.

Isuzu B-series engines are direct injection diesel engine comprising 4 cylinder light duty and 6 cylinder medium duty versions. These engines have been marketed on a worldwide basis not only for vehicle use but also for industrial and marine use. The production volume in 1987 was NO.1 in the world in this class. This paper describes the general outline of B-series engines and the 6BG1TC model with turbocharger and intercooler which develops the highest maximum output of these engines. This engine was developed in 1985 for the first time for medium duty truck in the domestic market and introduced in USA market in 1988. For the moment, our engineering efforts are directed to clear USA exhaust emission regulation for 1991.