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Optimal Road Congestion Charging Model in Mixed Driving Environment of Connected Autonomous Vehicle and Human-Driven Vehicle
LI Hao, KANG Liujiang, LUO Sida, SUN Huijun, WU Jianjun
Acta Scientiarum Naturalium Universitatis Pekinensis    2023, 59 (5): 747-756.   DOI: 10.13209/j.0479-8023.2023.066
Abstract256)   HTML    PDF(pc) (1875KB)(108)       Save
In order to get the optimal road congestion charging scheme in mixed driving environment of connected autonomous vehicles (CAV) and human-driven vehicles (HDV), this paper conducts a quantitative analysis of the impact of CAV on road networks (especially on road capacity), and analyzes the functional relationship between the road capacity and HDV flows as well as CAV flows. Secondly, the traditional Bureau of Public Road (BPR) Function is improved, and the system optimal allocation model is established based on the new BPR function. The system optimum (SO) assignment is performed on the traffic flow under the conditions of different CAV proportions and different HDV-CAV headways. Then, Frank-Wolfe algorithm is used to solve the SO model, by considering the extra traffic cost of HDV in the differences of SO results under different conditions. The corresponding road networks are formulated using the optimal toll theory charge plan. Finally, the model and the algorithm are applied to the Nguyen-Dupuis transportation network. The results show that under the coexisting condition of HDV and CAV, the marginal cost under the optimal allocation result of the system is the optimal congestion charging which can be the basis for the road toll scheme design under the coexistence of HDV and CAV.
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Chinese Critical Thinking: Structure and Measurement
HOU Yubo, LI Qiangqiang, LI Hao
Acta Scientiarum Naturalium Universitatis Pekinensis    2022, 58 (2): 383-390.   DOI: 10.13209/j.0479-8023.2022.001
Abstract843)   HTML    PDF(pc) (595KB)(303)       Save
Based on Byrnes’ definition and theory of critical thinking, through the research of approximately 1000 college and adult subjects, the authors have determined the structure of critical thinking of Chinese people and compiled the corresponding scale. In order to verify Byrnes’s theory of critical thinking structure, the authors first interviewed 40 subjects and generated a question bank for measuring critical thinking. Then, a preliminary scale was compiled. Second, an exploratory factor analysis was conducted on the data of 284 college students and the three dimensions of Chinese critical thinking — analytic ability, open-minded to criticism, and effort to use critical thinking, were obtained. Third, the authors conducted a confirmatory factor analysis on the data of 168 subjects, which confirmed the fit of the three-dimensional model. Finally, the data of 586 subjects were analyzed to further prove the reliability and validity of the scale. The result shows that the scale to measure the critical thinking of Chinese people conform to the theoretical constructs of Byrnes and colleagues. This scale has important theoretical and practical significance for future research in related fields.
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Effects of Silver Nanoparticles on the Accumulation of Cadmium by Lettuce (Lactuca sativa)
LI Haoyang, WANG Qi, TAN Guangcai, XU Nan
Acta Scientiarum Naturalium Universitatis Pekinensis    2016, 52 (6): 1077-1084.   DOI: 10.13209/j.0479-8023.2016.114
Abstract954)   HTML    PDF(pc) (919KB)(685)       Save

The effect of nanoparticle or ionic silver on cadmium accumulation by lettuce (Lactuca sativa) was investigated. The lettuce plants were grown in Hoagland solution amended with 0, 10, 100, 1000 μg/L nanoparticle silver or 0.1, 1, 10 μg/L ionic silver. Half of the lettuce were exposed to 50 μg/L ionic cadmium. After 35 days of exposure, wet weight, dry weight, cadmium, chlorophyll and malondialdehyde of leaves and roots of the lettuces were measured. Results show that except for the 1000 μg/L nanoparticle silver which increased cadmium concentration by about 200% (p<0.001) in lettuce roots, other concentrations of nanoparticle or ionic silver do not significantly change the cadmium concentration in either leaves or roots. Biomass, chlorophyll and malondialdehyde of the lettuces are not significantly changed either. Nanoparticle silver applied as agricultural fungicide in practical amounts will not lead to increased cadmium accumulation or detectable phytotoxicity symptoms in lettuce.

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Study on Depth of Atmospheric Boundary Layerin Gobi Desert Regions of the Bosten Lake Basin
YANG Yang, LIU Xiaoyang, LU Zhenghui, LI Hao
Acta Scientiarum Naturalium Universitatis Pekinensis    2016, 52 (5): 829-836.   DOI: 10.13209/j.0479-8023.2015.145
Abstract1506)   HTML    PDF(pc) (1148KB)(1139)       Save

Due to the combined effects of lake and Gobi, the atmospheric boundary layer located in Gobi desert regions of the Bosten Lake basin is found to possess some special regional characteristics. Based on the data of the developing meteorological observation experiments conducted in the Bosten Lake of Xinjiang Province, the height characteristics of the atmospheric boundary layer from May 21 to August 28, 2013 are analyzed. The result shows that the most prominent feature of the Gobi area of the Bosten Lake Basin is that the boundary layer often has the deep convection during the typical sunny days in the summer. The statistics also shows that in 45 days out of 100 days, the average height of the atmospheric boundary layer is above 3000 m, and the maximum height reaches 4400 m. The causes of forming the deep convective boundary layer are explored. It is argued that the atmospheric thermodynamic properties and the lake wind shear are important factors to form the deep convective boundary layer.

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EmBIOS: A BIOS Design for Embedded System Supporting MS Windows
LI Hao,ZHENG Yansong,PANG Jiufeng,TONG Dong,CHENG Xu
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract804)      PDF(pc) (2751KB)(465)       Save
The authors present EmBIOS, a compatible BIOS design for embedded system to support desktop OS such as MS Windows. To effectively achieve OS compatiblity, a simulator BIOS which could boot desktop OS in simulator environment is divided into multiple interrupt service routines. Then by extending and transplanting interrupt service routines to traditional embedded firmware environment, EmBIOS enables initialization of embedded system with existing firmware, and provides BIOS compatibility required by desktop OS. The functional correctness and OS compatibility are guaranteed through running windows and its typical applications on PKUnity86 FPGA and silicon. Experimental results demonstrate that the portability of EmBIOS design and its acceptable boot up performance compared with a commercial embedded BIOS.
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Analysis and Practice of a SoC Hardware Kernel for MS Windows
ZHENG Yansong,TONG Dong,LI Hao,PANG Jiufeng,WNAG Keyi,CHENG Xu
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract717)            Save
The authors study a method that develops a SoC hardware kernel for MS Windows. The method captures the basic system function specification of hardware kernel through multiple simulation execution and gradual drawoff, on the premise that the system is MS Windows compatible. The experiment indicates that the complexity of the hardware kernel is simpler drastically than that of the whole system, and that the requirement of hardware kernel among MS Windows versions is different obviously. Moreover, the SoC hardware kernel for MS Windows 98 is verified on the FPGA prototype.
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Gene Difference Expression Between Mice and Microtus fortis Infected with Schistosoma japonicum Using cDNA Microarrays
SUN Jun,LIN Jiaojiao,CHENG Guofeng,LI Hao,SHI Yaojun,LU Ke,CAI Youmin,JIANG Hongbo
Acta Scientiarum Naturalium Universitatis Pekinensis   
Abstract658)            Save
Gene difference expression of the lung tissues between of mice and Microtus fortis infected with Schistosoma japonicum for 7d, and the lung tissues and the liver tissues of Microtus fortis infected with Schistosoma japonicum for 12d were analyzed by cDNA microarrays. The results showed that serine protease inhibitor genes expression was up-regulated and immune-associated genes expression were not obviously changed in the lung tissues of mice. On the contrary, serine protease inhibitor genes expressed constantly in the lung tissues of Microtus fortis infected with Schistosoma japonicum for 7d and Several non specific immune associated genes (such as lysozyme gene and cathepsin genes) were up-regulated. At the same time, some important specific immune associated genes(such as CD74、MHCⅡ and MHCⅠ) were up-regulated. The lung tissues and liver tissues of Microtus fortis infected with Schistosoma japonicum for 12d also confirmed the results by enhancing expression of the non specific immune associated genes and specific immune associated genes. Furthermore, in the lung tissues of Microtus fortis infected with Schistosoma japonicum for 12d serine protease inhibitor genes expression were down-regulated. It was suggested that the mice and Microtus fortis share reverse expression patterns, which was helpful to deeply understand the molecular mechanism of natural resistance of Microtus fortis to Schistosoma japonicum.
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