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Machine Learning-Based Temperature and Wind Forecasts in the Zhangjiakou Competition Zone during the Beijing 2022 Winter Olympic Games

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Journal of Meteorological Research 2024年第4期38卷 664-679页

作者： Zhuo SUN Jiangbo LI Ruiqiang GUO Yiran ZHANG Gang ZHU xiaoliang yang China Meteorological Administration Xiong'an Atmospheric Boundary Layer Key Laboratory Xiong'an New Area 071800 Hebei Key Laboratory of Meteorology and Ecological Environment Shijiazhuang 050021 Hebei Meteorological Observatory Shijiazhuang 050021 College of Computer and Cyber Security Hebei Normal UniversityShijiazhuang 050024

Weather forecasting for the Zhangjiakou competition zone of the Beijing 2022 Winter Olympic Games is a challenging task due to its complex *** weather prediction models generally perform poorly for cold air pools and winds over complex terrains,due to their low spatiotemporal resolution and limitations in the description of dynamics,thermodynamics,and microphysics in mountainous *** study proposes an ensemble-learning model,named ENSL,for surface temperature and wind forecasts at the venues of the Zhangjiakou competition zone,by integrating five individual models—linear regression,random forest,gradient boosting decision tree,support vector machine,and artificial neural network(ANN),with a ridge regression as meta *** ENSL employs predictors from the high-resolution ECMWF model forecast(ECMWF-HRES) data and topography data,and targets from automatic weather station *** categories of predictors(synoptic-pattern related fields,surface element fields,terrain,and temporal features) are fed into *** results demonstrate that ENSL achieves better performance and generalization than individual *** root-mean-square error(RMSE) for the temperature and wind speed predictions is reduced by 48.2% and 28.5%,respectively,relative to *** the gust speed,the performance of ENSL is consistent with ANN(best individual model) in the whole dataset,whereas ENSL outperforms on extreme gust samples(42.7% compared with 38.7% obtained by ECMWF-HRES in terms of RMSE reduction).Sensitivity analysis of predictors in the four categories shows that ENSL fits their feature importance rankings and physical explanations effectively.

关键词： machine learning ensemble learning post-processing cold air pools mountain Beijing 2022 Winter Olympic Games

Cas12a-based on-site, rapid detection of genetically modified crops

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Journal of Integrative Plant Biology 2022年第10期64卷 1856-1859页

作者： Zhiqiang Duan xiaoliang yang Xingkun Ji Ying Chen Xiaomu Niu Anping Guo Jian‐Kang Zhu Feng Li Zhaobo Lang Hui Zhao Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off‐Season Reproduction Regions Institute of Tropical Bioscience and Biotechnology&San Ya Research InstituteChinese Academy of Tropical Agricultural SciencesHaikou 571101China Bellagen Biotechnology Co.Ltd. Jinan 250000China College of Life Sciences Shandong Normal UniversityJinan 250014China Institute of Advanced Biotechnology and School of Life Sciences Southern University of Science and TechnologyShenzhen 518055China Center for Advanced Bioindustry Technologies Chinese Academy of Agricultural SciencesBeijing 100081China Hainan Yazhou Bay Seed Lab SanyaHainan 572024China Shanghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 201602China

Genetically modified(GM)crops that impart herbicide resistance,improved tolerance to biotic and abiotic stresses,and enhanced yield or nutritional quality have been developed and grown worldwide(ISAAA Brief 55-2019:International Servicefor theAcquisition ofAgri-biotech Applications(ISAAA),2019).In response topublic concern on genetically modified organisms(GMOs),DNA-based and protein-based methods have been developed to detect GMOs infood/feed samples(Fraitureetal.,2015).These methods,however,require expensive equipment and technical expertise and are unsuitable for field diagnosis(DNA-based methods)or cannot detect non-coding sequences such as promoters or terminators(protein-based methods).

关键词： crops modified diagnosis

An adaptive policy-based framework for China's Carbon Capture and Storage development

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Frontiers of Engineering Management 2019年第1期6卷 78-86页

作者： xiaoliang yang Wolfgang HEIDUG Douglas COOKE World Resources Institute Washington D. C. USAKing Abdullah Petroleum Studies and Research Center Riyadh Saudi Arabia King Abdullah Petroleum Studies and Research Center Riyadh Saudi Arabia

China's political leadership has taken an increasingly public and proactive stance on climate change since 2014. This stance includes making a commitment that Chinese carbon dioxide (CO2) emissions will peak around 2030 and enacting measures through the 13th Five- Year Plan to support energy efficiency, clean energy technology, and carbon management. Chinese policymakers consider carbon capture and storage (CCS) a critical bridging technology to help accelerate the decarbonization of its economy. This paper reviews and analyzes Chinese CCS support policies from the perspective of an adaptive policymaking framework, recognizing uncertainty as an inherent element of the policymaking process and drawing general lessons for responding to changing circumstances. Notably, the political support for CCS in China remains fragmented with uncoordinated government leadership, undecided industry players, and even with opposing voices from some leading scientists. There is scope for expanding the framework to provide more granularity, in particular relating to the development of a CCS infrastructure and the development of storagefocused CO2-EOR. Overall, given the role CCS can play to decarbonize China's power and other industrial sectors, a commitment to CCS from top policymakers and major stakeholders is needed.

关键词： CCS policy climate change China

The Impacts of Different Bromide Concentrations and Advanced Oxidation Ways on the Bromate Generation

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Meteorological and Environmental Research 2015年第1期6卷 55-58页

作者： yang xiaoliang Jia Ruibao Sun Shaohua Song Wuchang Jinan Water Supply and Drainage Monitoring Center Shandong Province City Water Supply and Drainage Water Quality Monitoring Center

Taking reservoir water diverting from Yellow River as raw water, and using 5 m^3/h of pilot device, the impacts of different bromide concentrations and advanced oxidation ways on bmmate generation in effluent of ozone -upward flow BAC -sand filtration technology. Results showed that when bromine ion of raw water was about 100 μg/L, and ozone dosage was 2 mg/L, bromate exceeding risk existed in the effluent of ozone - upward flow BAC technology, and bromate content in the effluent reached 10 μg/L. Moreover, generation amount of bromate had certain linear rela- tionship with bromine ion of influent. Both dosing hydrogen peroxide and potassium permanganate could effectively inhibit bromate production, and there was no bromate generation in final effluent of the technology. Moreover, it also could improve the removal of major pollutants in the water by the combined process. Compared with advanced oxidation of hydrogen peroxide, potassium permanganate pre-oxidation could better control production costs.

关键词： Bromate Reservoir water from Yellow River Hydrogen peroxide Potassium permanganate Ozone China

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三角翼机翼摇滚主动控制多学科耦合数值模拟

航空学报 2021年第12期42卷 162-171页

作者：杨起刘伟杨小亮李昊国防科技大学空天科学学院长沙410072

细长机身和大后掠机翼气动构型的飞行器大攻角飞行时,由于缺少横向阻尼,易发生以绕体轴滚转振动为主的摇滚运动,飞行安全受到严重威胁。针对三角翼摇滚问题,采用动网格技术,建立了气动、运动和控制多学科耦合的数值模拟方法。通过耦合... 详细信息

细长机身和大后掠机翼气动构型的飞行器大攻角飞行时,由于缺少横向阻尼,易发生以绕体轴滚转振动为主的摇滚运动,飞行安全受到严重威胁。针对三角翼摇滚问题,采用动网格技术,建立了气动、运动和控制多学科耦合的数值模拟方法。通过耦合非定常Navier-Stokes方程、刚体运动方程和经典控制律,采用控制面差动偏转的方式对三角翼摇滚主动控制过程进行了数值模拟,并分析了不同控制状态下三角翼受控滚转的运动特性。在来流马赫数为0.3的条件下,实现了80°后掠三角翼摇滚现象的有效控制。

关键词：三角翼多学科耦合机翼摇滚主动控制后缘控制面

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高超声速飞行器自适应减阻盘动态减阻机理

航空学报 2023年第4期44卷 160-172页

作者：韩荣刘伟杨小亮国防科技大学空天科学学院长沙410073

针对高超声速飞行器在动态机动过程中的减阻问题,基于非定常流动/运动耦合计算方法及动态混合网格生成技术,对自适应减阻盘在高超声速飞行器机动过程中的动态减阻效果开展研究,并分析飞行器阻力特性随不同参数的变化规律,为高超声速飞... 详细信息

针对高超声速飞行器在动态机动过程中的减阻问题,基于非定常流动/运动耦合计算方法及动态混合网格生成技术,对自适应减阻盘在高超声速飞行器机动过程中的动态减阻效果开展研究,并分析飞行器阻力特性随不同参数的变化规律,为高超声速飞行器设计及优化提供一定的参考。同时,通过与固定式减阻盘对比,探讨2种方法在减阻机理上的差异。研究发现,在高超声速飞行器机动过程中,自适应减阻盘始终对准来流,有助于维持钝体前方回流区结构,有攻角状态下依然具有流场重构作用。相对于固定式减阻盘,在强迫俯仰振荡过程中,采用自适应方法后,80%以上的时间中减阻效果提升明显;且随着俯仰角增大,自适应方法的优势愈发显著。

关键词：高超声速飞行器自适应减阻盘减阻机理动态混合网格技术非定常数值模拟

Pilot Study on Powder Active Carbon / Flotation/Microflocculation / Ultrafiltration Combined Process for Treatment of Reservoir Water

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Meteorological and Environmental Research 2013年第12期4卷 57-60页

作者： Wuchang Song Mantun Li xiaoliang yang Ruibao Jia Shaohua Sun Urban Water Monitoring Center of Shandong Province Beijing University of Technology University of Jinan

[Objective] The study aimed to discover the effects of powder active carbon（ PAC） /flotation /micro-flocculation /ultrafiltration combined process on the treatment of reservoir water. [Method]Taken the water from a mountainous reservoir for the initial samples,the parameters such as turbidity,COD Mn,chlorophyll-a and methylisobormeol（ MIB） of water samples were monitored before and after treated with combined processes of micro-flocculation /ultrafiltration, flotation /micro-flocculation /ultrafiltration, PAC /flotation /micro-flocculation /ultrafiltration. [Result] The results showed that the removal rates of turbidity of water samples by the above three processes were 97. 5%,98. 0% and 98. 6%,respectively. The removal rates of COD Mn were 30. 9%,35. 0% and 52. 0%. The removal rates of chlorophyll-a were 80. 6%,91. 0% and 99. 0%. The removal rates of MIB were 17. 0%,34. 2% and 97. 0%. [Conclusion]The PAC /flotation /micro-flocculation ultrafiltration combined process can be flexibly combined based on the characteristics of algae and odor in water,and is suitable for water plant construction or reconstruction.

关键词： Ultrafiltration Flotation Micro-flocculation Powder active carbon China

不同养护温度下充填体-围岩胶结面剪切破坏特征

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土木工程学报 2022年第4期55卷 76-87页

作者：杨孝亮王文杰武汉科技大学资源与环境工程学院湖北武汉430081 武汉科技大学冶金矿产资源高效利用与造块湖北省重点实验室湖北武汉430081

针对深井矿山高地温影响充填体-围岩胶结面剪切破坏特征的问题,开展了养护温度20℃、40℃、60℃和80℃,法向应力为0、0.3MPa、0.6MPa的充填体-围岩胶结面剪切试验,并利用三维激光扫描系统对剪切断面进行扫描,获取断面的破坏特征和参数... 详细信息

针对深井矿山高地温影响充填体-围岩胶结面剪切破坏特征的问题,开展了养护温度20℃、40℃、60℃和80℃,法向应力为0、0.3MPa、0.6MPa的充填体-围岩胶结面剪切试验,并利用三维激光扫描系统对剪切断面进行扫描,获取断面的破坏特征和参数。研究结果表明:养护温度和法向应力均对充填体-围岩胶结面剪切强度和破坏特征有明显影响。养护温度增大,法向应力不变时,胶结面的抗剪强度先增大再减小,40℃时剪切强度最高;养护温度不变,法向应力增大时,胶结面抗剪强度呈线性增大;断面三维形貌特征参数S_(p)、S_(v)、S_(z)、S_(a)和S_(q)的大小与法向应力的变化呈反比,养护温度变化时其变化趋势与强度变化规律相反,40℃时达到最小值,而S_(sk)的大小与养护温度、法向应力大小无明显关联,S_(ku)的大小随法向应力的增大而增大,养护温度变化时其变化趋势为与抗剪强度变化规律相同。研究结果可为深部矿山井下充填体强度设计和顶板稳定性分析提供理论依据。

关键词：养护温度充填体胶结面剪切强度破坏特征

Influences of Carbon Content on the Properties and Microstructure of Ultrafine WC-10Co Cemented Carbide

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Journal of Wuhan University of Technology(Materials Science) 2007年第3期22卷 473-477页

作者：史晓亮 State Key Laboratory of Advanced Technology for Materials Synthesis & Processing Wuhan University of Technology

WC-10Co nanocrystalline composite powders prepared by spray pyrogenation-continuous reduction and carburization technology were consolidated by vacuum sintering plus hot isostatic pressing （HIP）. Influences of carbon content on properties and microstructure of ultrafine WC-10Co cemented carbide were investigated. The results show that the relative density of the ultrafine WC-10Co cemented carbides can reach 99.72%, and the transverse rupture strength （TRS） was higher than 3 890 MPa, Rockwell A hardness （HRA） was higher than 92.5, the average grain size was less than 460 nm, when carbon content in nanocrystalline composite powder was 5.54wt% and the ball-milled time was 48 hours, ultrafine WC-10Co cemented carbide with excellent properties and homogeneous microstructure was obtained.

关键词： WC-10Co nanocrystalline composite powder carbon content mechanical properties microstructure