Publications by authors named "Xiumin Yu"

Ensuring driving operational safety in emergency scenarios is paramount for autonomous vehicles to prevent accidents, particularly when vehicle motion completely depends on autonomous systems. Numerous factors must be evaluated when designing emergency collision avoidance strategies for critical situations, such as trajectory feasibility, vehicle motion stability, and driver comfort. Therefore, this study proposes a framework for emergency operation that uses collision-free area calculations to inform maneuver decisions and facilitate collision avoidance trajectory planning, preventing vehicle collisions.

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Teacher occupational wellness and effectiveness are crucial aspects of a teacher's capacity to contribute to the advancement of excellence in education. Nevertheless, there is a dearth of considerable studies regarding the interconnections between work passion and emotion regulation in higher education. This study developed a model to demonstrate the interplay between the above-mentioned constructs to fill this research gap.

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-Butanol, as a biological alternative fuel containing oxygen, has similar physical and chemical properties to gasoline and has a wide range of sources, which has attracted more and more attention and research. Direct injection technology has been widely used in the field of internal combustion engine due to its advantages of flexibility and control ability. In this paper, the secondary injection of -butanol engine under the mode of in-cylinder direct injection is discussed to organize stratified combustion of the mixture, optimize combustion to improve the thermal efficiency, and reduce emission.

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Perovskite quantum dots (PQDs) as recently emerging electrochemiluminescence (ECL) luminophores have been paid much attention due to their good ECL activity, narrow ECL spectra, and easy preparation. However, the PQDs used for ECL sensing were mainly inherited from those PQDs prepared as strong fluorescence (FL) luminophores, which would limit the finding of highly ECL PQDs for sensing due to the very different mechanisms in generating excited-state luminophores between ECL and FL. In order to obtain highly electrochemiluminescent PQDs, for the first time we proposed to synthesize PQDs for ECL sensing rather than for FL-based analysis by optimizing the synthesis conditions.

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Oxygen-enriched combustion (OEC) technology in SI engines can greatly improve the degree of constant volume combustion, increase the torque output, and reduce HC and CO emissions but lead to a sharp increase in NO emissions. Simultaneously, the high temperature from OEC would lead to high nucleation particle emissions. Under the OEC mode, except the oxygen content, spark timing and engine load are important influencing factors on emissions.

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Conventional ethanol spark ignition (SI) engines have poor fuel atomization and mixture formation. The objective of this paper is to improve the combustion and emission performance of ethanol SI engines under lean-burn conditions through the dual-injection mode with ethanol port injection and compressed natural gas (CNG) direct injection (CDI+EPI). This paper studies the engine performance at 1500 rpm under five CNG direct injection ratios (CDIr) and five excess air ratios (λ).

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Article Synopsis
  • - This study tested how injecting hydrogen affects combustion in a n-butanol engine that runs on a lean air-fuel mix, using a special dual fuel injection system designed for this purpose.
  • - Results showed that as the amount of hydrogen increased, certain combustion measurements like cylinder pressure and efficiency improved, while the variations in combustion cycles decreased.
  • - Specifically, a 5% hydrogen blend significantly enhanced stability in combustion cycles at an air-fuel ratio of 1.0, indicating that hydrogen direct injection can improve combustion stability under lean burn conditions.
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Ethanol is usually combined with gasoline to manufacture ethanol-gasoline with excellent combustion characteristics. However, extracting water from hydrous ethanol to manufacture anhydrous ethanol consumed much energy, which increases the production cost of ethanol-gasoline. Many researchers have studied the combustion and emissions of hydrous ethanol-gasoline to explore the application of hydrous ethanol-gasoline as the fuel for spark-ignition engines.

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Arsenic is widely distributed in the environment. As teratogen, carcinogen or mutagen, it has extremely toxic effect on mammalian health. Recently, as the outbreaks of arsenicosis in many countries such as Bangladesh and China, arsenic toxicity or pollution has been a global problem, severely threatening tens of millions of people's health.

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