Fault diagnosis and maintenance of automobile engine cooling system

With the further development of the society, the economic level of Chinese residents is gradually improving. Under such circumstances, the number of automobiles and their usage are increasing as well. As a kind of mechanical equipment, there will be many application faults of the automobile after long-term use. Only by solving the faults can automobiles be restarted and run stably for a long time. Based on this, this paper focuses on automobile maintenance, analyzes the principle of engine cooling system, and studies the diagnosis and maintenance methods of this kind of fault, trying to provide some reference value for the further discussion and research in this field.

Optimization and performance analysis of the power system in hybrid electric vehicles

Hybrid electric vehicles (HEV) are the most industrialized and marketable in electric vehicles. Referring to the basic structure and parameters adopted by PRIUS Hybrid of Toyota, this paper puts forward an optimization scheme of HEV. The parameters and type selection of power components are obtained according to the vehicle's dynamic formula. The optimized hybrid power system is built and simulated through the simulation platform AVL Cruise. Then the obtained economic and dynamic parameters are analyzed and compared with the original performance parameters, verifying that the optimized system has better performance.

Analysis on key maintenance technologies of new energy vehicles

With the continuous development of the society and improvement of the national economic level in China, people's life has undergone enormous changes in many aspects, the demand for transportation has gradually increased, and various transportation modes have emerged. At present, environmental pollution is becoming increasingly serious as automobile exhaust has become one of the main factors of air pollution. Under such circumstances, new energy vehicles have emerged and become increasingly popular in society, actively responding to the scientific and sustainable development strategy called for by China's government. This paper mainly studies the maintenance technology of new energy vehicle engines, hoping to provide help for the development of China's new energy vehicle industry.

Research on construction of vehicle driving cycle based on Markov chain and global K-means clustering algorithm

Vehicle driving cycle is a time-speed curve used to describe vehicle driving rules. The research and development of vehicle driving cycle not only provide theoretical basis for the test of vehicle fuel’s economy and pollutant emission level, but also guide the design and development of new models in the future. This paper adopts the actual driving data of light vehicles in Fuzhou City, Fujian Province collected by China Automotive Technology Research Center (CATC) through the data collection system, and analyzes and verifies the new data after standardized dimension reduction by combining the global K-means clustering and Markov chain principle. The specific work is divided into the following parts: 1. The global K-means clustering algorithm adopted to cluster the kinematic segment database after standardized dimension reduction; 2. Markov chain is applied to construct the working condition diagram. The basic principle of this method is to regard the short-stroke speed-time sequence as a complete random process, divide the speed intervals by lines, each of which represents a different speed state, and convert the speed into a speed state, so that the speed-time sequence becomes a state-time sequence. Since the next state is only related to the current one, a group of random state sequences can be randomly generated by the program as long as the transition probability between two adjacent states is determined and the matrix of state transition probability is established. 3. The state sequence is converted into a speed sequence, and finally a set of driving cycle conforming to the spatial characteristics of the samples is obtained.

Research on technological innovation model and performance analysis of new energy vehicles

New energy vehicles are widely used in the transportation industry of various countries in the 21st century, which not only saves energy and protects environment, but also effectively promotes the development of China's transportation industry. At present, the main energy sources used by new energy vehicles are electric power and clean fuels. To ensure the normal running, attention should be paid to innovating technological modes and analyzing performance, which is the topic of this paper.

Hirschfeld surface analysis and short-range ferromagnetic ordering in La0.5Ca0.4Ag0.1MnO3 based on critical behavior study

We investigated the Hirschfeld surface analysis and critical behaviour in La0.5Ca0.4Ag0.1MnO3 near the second-order ferromagnetic phase transition at Curie temperature TC. We determined the critical exponents, β, γ and δ corresponding to the temperature dependence of spontaneous magnetization, initial susceptibility and isothermal magnetization, respectively. The study of Hirshfeld surface reflects that both the electrostatic and intermolecular interactions are short range. The values for critical exponents obtained from magnetic measurements are very close to those predicted by the mean field tri-critical model. The critical-exponent values deduced here were in a good conform to those obtained using the modified Arrott plot and Widom scaling relation.

WHEN MAKING MONEY IS MORE IMPORTANT THAN SAVING LIVES: REVISITING THE FORD PINTO CASE

Despite a long tradition of ethics training in business colleges, managers commonly make unethical business decisions. This paper reports a five year study of ethical decision making of business students (n = 192). In an undergraduate microeconomics course, students were presented with financial data from the infamous Ford Pinto case where defective engineering, coupled with unethical management behavior, resulted in a number of fiery fatalities. Facing the decision to repair the cars or pay the estimated costs of lost wrongful death lawsuits, 56.8% of students chose to pay for the deaths. This paper describes the classroom experiment and uses logistic regression to compare the characteristics of the group choosing the correct ethical decision (repair the cars), with the group choosing the incorrect ethical decision (pay for the deaths).

Evaluating On-Road Emissions Impacts of HEVs, PHEVs and EVs: An Integrated Modeling Framework

This paper develops a framework to evaluate HEVs, PHEVs and EVs on-road emissions impact, by integrating endogenous vehicle consumer choice model and MOVES-based regional emission transportation model. A case study based on Harris County, Texas data is implemented to examine the on-road emissions under different market penetrations (due to different future energy price) and government policies. The results show different on-road transportation emissions level for Carbon Dioxide (CO2), Carbon Monoxide (CO), Nitrogen Oxide (NOx) and Total Hydrocarbon (THC). In addition, cost effectiveness of reducing on-road emissions by extending tax credit for plug-in electric vehicles (PEV) is calculated and reported.

Evaluating On-Road Emissions Impacts of HEVs, PHEVs and EVs: An Integrated Modeling Framework

This paper develops a framework to evaluate HEVs, PHEVs and EVs on-road emissions impact, by integrating endogenous vehicle consumer choice model and MOVES-based regional emission transportation model. A case study based on Harris County, Texas data is implemented to examine the on-road emissions under different market penetrations (due to different future energy price) and government policies. The results show different on-road transportation emissions level for Carbon Dioxide (CO2), Carbon Monoxide (CO), Nitrogen Oxide (NOx) and Total Hydrocarbon (THC). In addition, cost effectiveness of reducing on-road emissions by extending tax credit for plug-in electric vehicles (PEV) is calculated and reported.

Kinematics and Dynamics Analysis of McPherson Suspension Based on Planar 1/4 Vehicle Model

The nonlinear asymmetric problem of McPherson suspension has become a challenging problem in the process ofestablishing the system model. This paper presents a planar 1/4-vehicle model that not only takes into account thevertical vibration of the sprung mass (chassis), but also includes: ix spring mass (wheel assembly) sliding and rotation;ii longitudinal wheel mass And its moment of inertia; iii tire damping and lateral defl ection. This dynamic kinematicmodel provides a solution to two important shortcomings of the traditional 1/4 vehicle model: it explains geometricmodeling and tire modeling. This paper provides a systematic development of the planar model and a completemathematical equation. This analysis model can be applied to hardware in the rapid calculation of ring applications. Inaddition, the model also gives a repeatable Simulink simulation implementation. The model has been compared withthe actual Adams / View simulation to analyze the vibration and rebound motion of the wheel, as well as two relatedmotion parameters: the dynamic characteristics of the camber and the pitch change.