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3D Motion Parameters Determination Based on Binocular Sequence Images

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Geo-Spatial Information Science 2006年第1期9卷 32-37页

作者： zhang Jianqing zhang Chunsen HE shaojun School of Remote Sensing and Information Engineering Wuhan University 129 Luoyu Road Wuhan 430079 China

Exactly capturing three dimensional (3D) motion i nf ormation of an object is an essential and important task in computer vision, and is also one of the most difficult problems. In this paper, a binocular vision s ystem and a method for determining 3D motion parameters of an object from binocu lar sequence images are introduced. The main steps include camera calibration, t he matching of motion and stereo images, 3D feature point correspondences and re solving the motion parameters. Finally, the experimental results of acquiring th e motion parameters of the objects with uniform velocity and acceleration in the straight line based on the real binocular sequence images by the mentioned meth od are presented.

关键词： binocular sequence image camera calibration image matching motion parameter

Study on the breakup length of circular impinging jet

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Journal of University of Science and Technology Beijing 2007年第6期14卷 585-588页

作者： Shengyong Li Mouwei Li shaojun zhang Bangwen Wang Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

Circular impinging jet, which is widely used in accelerated control cooling （ACC） equipment to accelerate the cooling of hot rolled plates, is subject to breakup, and may result in undesirable cooling effect. Therefore, the jet breakup should be avoided as possible in industrial production. The objective of this study is to find the relation of the processing parameters of the ACC equipment versus the breakup length of jet with weaker turbulence. To obtain quantitative findings, not only relative experimental study but also numerical simulation was carded out. For a weaker turbulent water jet, the breakup length increases with the increase of jet diameter, as well as with the jet velocity; jet diameter has a significant effect on the breakup length for a certain flow rate when compared with jet velocity; finally a suggested correlation of the jet breakup length versus jet Weber number is presented in this study.

关键词： hot rolled plate circular impinging jet breakup length numerical simulation

Data quality evaluation and calibration of on-road remote sensing systems based on exhaust plumes

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Journal of Environmental Sciences 2023年第1期123卷 317-326页

作者： Shijie Liu Xinlu zhang Linlin Ma Liqiang He shaojun zhang Miaomiao Cheng State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Institute of Atmospheric Environment Chinese Research Academy of Environmental SciencesBeijing 100012China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly *** achieve the precise control of emissions,on-road remote sensing(RS)technology has been developed and applied for law enforcement and ***,data quality is still an existing issue affecting the development and application of *** this study,the RS data from a cross-road RS system used at a single site(from 2012 to 2015)were collected,the data screening process was reviewed,the issues with data quality were summarized,a new method of data screening and calibration was proposed,and the effectiveness of the improved data quality control methods was finally *** results showed that this method reduces the skewness and kurtosis of the data distribution by up to nearly 67%,which restores the actual characteristics of exhaust diffusion and is conducive to the identification of actual clean and high-emission *** annual variability of emission factors of nitric oxide decreases by 60%-on average-eliminating the annual drift of fleet emissions and improving data reliability.

关键词： On-road remote sensing(RS) Data quality Spearman rank correlation Least-square regression with a non-zero intercept Cook value

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ESG标准体系构建研究

质量与认证 2025年第1期 56-59页

作者：张少君袁征郑天宇中国质量认证中心青岛分中心

在“双碳”目标发展的背景下,我国低碳绿色发展目标促使各行各业,尤其是央国企和大型龙头企业越来越重视ESG(环境、社会和治理)发展。目前,我国ESG还停留在政策指导水平。一方面,非强制性的政策导向导致大多数上市企业和非上市企业积极... 详细信息

在“双碳”目标发展的背景下,我国低碳绿色发展目标促使各行各业,尤其是央国企和大型龙头企业越来越重视ESG(环境、社会和治理)发展。目前,我国ESG还停留在政策指导水平。一方面,非强制性的政策导向导致大多数上市企业和非上市企业积极性不高。另一方面,我国ESG标准化建设缺失,导致企业的ESG报告和第三方机构的ESG评价评级参差不齐,前者是从企业自身角度进行自我管理、信息披露,后者是从第三方角度对ESG报告的客观评价评级,为市场规制提供工具、完善ESG标准,提升企业自身ESG报告和第三方机构对企业ESG报告评价的采信力度,链接自由市场和政府监管,助力我国实现“双碳”目标。

关键词： ESG ESG披露 ESG标准标准化双碳

Online recognition of the multiphase flow regime

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Science China(Technological Sciences) 2008年第8期51卷 1186-1194页

作者： BAI BoFeng zhang shaojun ZHAO Liang zhang XiMin GUO LieJin State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

The key reasons that the present method cannot be used to solve the industrial multi- phase flow pattern recognition are clarified firstly. The prerequisite to realize the online recognition is proposed and recognition rules for partial flow pattern are obtained based on the massive experimental data. The standard templates for every flow regime feature are calculated with self-organization cluster algorithm. The multi-sensor data fusion method is proposed to realize the online recognition of multiphase flow regime with the pressure and differential pressure signals, which overcomes the severe influence of fluid flow velocity and the oil fraction on the recognition. The online recognition method is tested in the practice, which has less than 10 percent measurement error. The method takes advantages of high confidence, good fault tolerance and less requirement of single sensor performance.

关键词： multiphase flow flow regime online recognition multi-sensor data fusion

Evaluating the emission status of light-duty gasoline vehicles and motorcycles in Macao with real-world remote sensing measurement

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Journal of Environmental Sciences 2014年第11期26卷 2240-2248页

作者： Yu Zhou Ye Wu shaojun zhang Lixin Fu Jiming Hao School of Environment State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex

Roadside remote sensing measurement was used to explore the real-world emission status of light duty gasoline vehicles （LDGVs） and motorcycles in Macao. Both fuel-based and distance-based emission factors were derived using the mass balance method. The emission concentration profile of LDGVs illustrated the benefits of tightening emission standards at the source country or region of import. The distance-based emission factors for CO, HC and NOx of LDGVs registered before 2000 were 8.00, 1.04 and 1.36 g/km, respectively. The distance-based emission factors for CO, HC and NOx of LDGVs registered in or after 2000 were 1.16, 0.15 and 0.18 g/km, respectively. The fuel-based CO emission factors of light duty motorcycles （LDMCs） and heavy duty motorcycles （HDMCs） registered before 2000 were about 10 times higher than those of LDGVs of the same age group. As the emissions of LDGVs decreased more quickly after 2000, the gap widens for newer vehicles. The distance-based HC emission factors of LDMCs and HDMCs registered before 2000 were 4.81 and 2.91 g/km, respectively. The distance-based HC emission factors of LDMCs and HDMCs registered in or after 2000 were 3.52 and 0.93 g/km, respectively. The poor emission performance of motorcycles and their larger share in the traffic flow will cause them to be the major contributor to traffic CO and HC emissions. LDMCs, especially two-stroke models, should be the priority for vehicle emission control efforts in Macao.

关键词： Emission Remote sensing Macao Motorcycle

Characterization of personal exposure concentration of fine particles for adults and children exposed to high ambient concentrations in Beijing, China

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Journal of Environmental Sciences 2010年第11期22卷 1757-1764页

作者： Xuan Du Qian Kong Weihua Ge shaojun zhang Lixin Fu Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Xi' an Municipal Engineering Design and Research Institute Co. Ltd. Xi'an 710068 China

In China, the health risk from overexposure to particles is becoming an important public health concern. To investigate daily exposure characteristics to PM 2.5 with high ambient concentration in urban area, a personal exposure study was conducted for school children, and office workers in Beijing, China. For all participants （N = 114）, the mean personal 24-hr exposure concentration was 102.5, 14.7, 0.093, 0.528, 0.934, 0.174 and 0.703 μg/m 3 for PM 2.5 , black carbon, Mn, Al, Ca, Pb, and Fe. Children’s exposure concentrations of PM 2.5 were 4–5 times higher than those in related studies. The ambient concentration of PM 2.5 （128.5 μg/m 3 ） was significantly higher than the personal exposure concentration （P 0.05）, and exceed the reference concentration （25 μg/m 3 ） of WHO air quality guideline. Good correlation relationships and significant differences were identified between ambient concentration and personal exposure concentration. The relationships indicate that the ambient concentration is the main factor influencing personal exposure concentration, but is not a good indicator of personal exposure concentration. Outdoor activities （commute mode, exposure to heating, workday or weekend travel） influenced personal exposure concentrations significantly, but the magnitude of the influence from indoor activities （exposure to cooking） was masked by the high ambient concentrations.

关键词： personal exposure PM 2.5 high ambient concentration

Research, development and application of compound-vertical-retort technology for magnesium production

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Journal of Magnesium and Alloys 2023年第12期11卷 4724-4736页

作者： Rongbin Li shaojun zhang Peixu Yang Jinhui Liu Fengqin Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Material Science and Engineering Zhengzhou UniversityZhengzhouHenan 450001China

This paper comprehensively introduces a new magnesium production technology the compound-vertical-retort technology, involving in the related fundamental researches, core equipment development, working flow, and technical characteristics. Scale-up test and an annual1200-ton-magnesium demonstration-level test was conducted to confirm the rationality, reliability, and advancement of the equipment, system and process design. It is indicated that the new technology solved a series of problems of traditional silicothermic process including adhesion and glaze, short life of retort, low efficiency, high impurity of crystallized magnesium, large heat losses, and poor working environment,making a great technological breakthrough in this field. Representatively, the new well-designed ceramic-lined steel retort serves 2~3 times in life than the normal retorts. The magnesium yield per retort is improved 4~5 times, with purity of >99.8%. The energy consumption in reduction stage is reduced by more than 20%. The mechanical production is fully realized and operating environment is significantly improved.

关键词： Silicothermic process Magnesium Compound retort Vertical retort Mechanization

An improved lattice Boltzmann model for high gas and liquid density ratio in composite grids

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Theoretical & Applied Mechanics Letters 2018年第5期8卷 326-333,362页

作者： shaojun zhang Wanqing Wu Qinggong Zheng Marine Engineering College Dalian Maritime University College of Naval Architecture and Marine Engineering Shandong Jiaotong University

Lattice Boltzmann method is one of the widely used in multiphase fluid ***,the two main disadvantages of this method are the instability of numerical calculations due to the large density ratio of two phases and impossibility of the temperature distribution to be fed back into the velocity distribution function when the temperature is *** on the combination prescribed by Inamuro,the large density ratio two-phase flow model and thermal model makes the density ratio of the model simulation to be increased to 2778:1 by optimizing the interface distribution function of two-phase which improves the accuracy of differential *** phase transition term is added as source term into the distribution function controlling two phase order parameters to describe the temperature effect on the gas-liquid phase *** latent heat generated from the phase change is also added as a source term into the temperature distribution function which simulates the movement of the flow under the common coupling of density,velocity,pressure and *** density and the temperature distribution of single bubble are *** of the simulation results with experimental results indicates a good agreement pointing out the effectiveness of the improved model.

关键词： Lattice Boltzmann model Density ratio Composite grids Bubble motion Temperature effect