About MAHLE & MAHLE Powertrain The MAHLE Group ranks amongst the top three systems suppliers worldwide for piston systems,cylinder components,valve train systems, air management systems,and liquid management syste...About MAHLE & MAHLE Powertrain The MAHLE Group ranks amongst the top three systems suppliers worldwide for piston systems,cylinder components,valve train systems, air management systems,and liquid management systems.For almost 90 years,MAHLE has played a decisive role in promoting展开更多
Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 °C. In the acidification digester, the main product was acetic acid, with t...Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 °C. In the acidification digester, the main product was acetic acid, with the maximum concentration of 4289 mg·L-1on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential(ORP) and NH+4-N level decreased gradually with hydraulic retention time(HRT)of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached9.6 × 1010ml-1at the organic loading rate(OLR) of 3.5–4 kg VS·m-3, with corresponding HRT of 12–16 days.Accordingly, the optimal biogas production was 0.62 m3·(kg VS)-1, with methane content of 65%–68%. ORP and NH+4-N levels in the methanizer remained between- 500 and- 560 m V and 2000–4500 mg·L-1, respectively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.展开更多
The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine operation.However,at top dead centers,the friction coefficient of the piston ...The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine operation.However,at top dead centers,the friction coefficient of the piston ring–cylinder liner pair is detrimental to the engine’s tribological performance.In this work,dimples with different texture dimensions and densities were tested in a home-developed tribometer.The friction coefficient was measured for all samples,and for those with the best results,their wear resistance was assessed.The texture with an aspect ratio of 0.25 and a density area of 15%reported the best tribological results.展开更多
Connected and automated vehicle(CAV) is a transformative technology that has great potential to change our daily life. Therefore, CAV related research has been advanced significantly in recent years. This paper does a...Connected and automated vehicle(CAV) is a transformative technology that has great potential to change our daily life. Therefore, CAV related research has been advanced significantly in recent years. This paper does a comprehensive review on five selected subjects that lie in the heart of CAV research:(i) inter-CAV communications;(ii) security of CAVs;(iii) intersection control for CAVs;(iv) collision-free navigation of CAVs; and(v)pedestrian detection and protection. It is believed that these topics are essential to ensure the success of CAVs and need to be better understood. For inter-CAV communications, this paper focuses on both Dedicated Short Range Communications(DSRC) and the future 5 G cellular technologies; for security of CAVs, this paper discusses both passive and active attacks and the existing solutions; for intersection control, this paper summarizes the pros and cons of both centralized and decentralized approaches; for collision avoidance, this paper concentrates on four subareas: maneuverability, vehicle networking, control confliction, and motorcycles; for pedestrian detection, this paper covers sensor, radar, and computer vision based approaches. Under each topic, this paper not only shows the stateof-the-art, but also unveils potential future research directions. By establishing connections among these subjects, this paper shows how they interact with each other and how they can be integrated into a seamless user experience. It is believed that the literature covered and conclusions drawn in this paper are very helpful to CAV researchers, application engineers, and policy makers.展开更多
文摘About MAHLE & MAHLE Powertrain The MAHLE Group ranks amongst the top three systems suppliers worldwide for piston systems,cylinder components,valve train systems, air management systems,and liquid management systems.For almost 90 years,MAHLE has played a decisive role in promoting
基金the National Science-Technology Support Plan of China(2014BAD02B04)
文摘Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 °C. In the acidification digester, the main product was acetic acid, with the maximum concentration of 4289 mg·L-1on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential(ORP) and NH+4-N level decreased gradually with hydraulic retention time(HRT)of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached9.6 × 1010ml-1at the organic loading rate(OLR) of 3.5–4 kg VS·m-3, with corresponding HRT of 12–16 days.Accordingly, the optimal biogas production was 0.62 m3·(kg VS)-1, with methane content of 65%–68%. ORP and NH+4-N levels in the methanizer remained between- 500 and- 560 m V and 2000–4500 mg·L-1, respectively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.
基金supported by Fundação para a Ciência e Tecnologia(FCT)and MAHLE,Componentes de Motores,S.A.through the grant SFRH/BDE/110654/2015by the project Add-Additive with the reference POCI-01-0247-FEDER-024533.
文摘The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine operation.However,at top dead centers,the friction coefficient of the piston ring–cylinder liner pair is detrimental to the engine’s tribological performance.In this work,dimples with different texture dimensions and densities were tested in a home-developed tribometer.The friction coefficient was measured for all samples,and for those with the best results,their wear resistance was assessed.The texture with an aspect ratio of 0.25 and a density area of 15%reported the best tribological results.
文摘Connected and automated vehicle(CAV) is a transformative technology that has great potential to change our daily life. Therefore, CAV related research has been advanced significantly in recent years. This paper does a comprehensive review on five selected subjects that lie in the heart of CAV research:(i) inter-CAV communications;(ii) security of CAVs;(iii) intersection control for CAVs;(iv) collision-free navigation of CAVs; and(v)pedestrian detection and protection. It is believed that these topics are essential to ensure the success of CAVs and need to be better understood. For inter-CAV communications, this paper focuses on both Dedicated Short Range Communications(DSRC) and the future 5 G cellular technologies; for security of CAVs, this paper discusses both passive and active attacks and the existing solutions; for intersection control, this paper summarizes the pros and cons of both centralized and decentralized approaches; for collision avoidance, this paper concentrates on four subareas: maneuverability, vehicle networking, control confliction, and motorcycles; for pedestrian detection, this paper covers sensor, radar, and computer vision based approaches. Under each topic, this paper not only shows the stateof-the-art, but also unveils potential future research directions. By establishing connections among these subjects, this paper shows how they interact with each other and how they can be integrated into a seamless user experience. It is believed that the literature covered and conclusions drawn in this paper are very helpful to CAV researchers, application engineers, and policy makers.
