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Artificial Intelligence Based Multi-Scenario mmWave Channel Modeling for Intelligent High-Speed Train Communications

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China Communications 2024年第3期21卷 260-272页

作者： zhang Mengjiao Liu Yu Huang Jie He Ruisi zhang jingfan Yu Chongyang Wang Chengxiang School of Microelectronics Shandong UniversityJinan 250101China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China The National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 210096China The Purple Mountain Laboratories Nanjing 211111China

A large amount of mobile data from growing high-speed train(HST)users makes intelligent HST communications enter the era of big *** corresponding artificial intelligence(AI)based HST channel modeling becomes a *** paper provides AI based channel characteristic prediction and scenario classification model for millimeter wave(mmWave)HST ***,the ray tracing method verified by measurement data is applied to reconstruct four representative HST *** setting the positions of transmitter(Tx),receiver(Rx),and other parameters,the multi-scenarios wireless channel big data is ***,based on the obtained channel database,radial basis function neural network(RBF-NN)and back propagation neural network(BP-NN)are trained for channel characteristic prediction and scenario ***,the channel characteristic prediction and scenario classification capabilities of the network are evaluated by calculating the root mean square error(RMSE).The results show that RBF-NN can generally achieve better performance than BP-NN,and is more applicable to prediction of HST scenarios.

关键词： artificial intelligence channel characteristic prediction HST channel millimeter wave scenario classification

P450-mediated dehydrotyrosine formation during WS9326 biosynthesis proceeds via dehydrogenation of a specific acylated dipeptide substrate

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Acta Pharmaceutica Sinica B 2023年第8期13卷 3561-3574页

作者： Songya zhang Lin zhang Anja Greule Julien Tailhades Edward Marschall Panward Prasongpholchai Daniel J.Leng jingfan zhang Jing Zhu Joe A.Kaczmarski Ralf B.Schittenhelm Oliver Einsle Colin J.Jackson Fabrizio Alberti Andreas Bechthold Youming zhang Manuela Tosin Tong Si Max J.Cryle CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Institut für Biochemie Albert-Ludwigs-Universitat FreiburgFreiburg 79104Germany Department of Biochemistry and Molecular Biology the Monash Biomedicine Discovery InstituteMonash UniversityClayton 3800VICAustralia EMBL Australia Monash UniversityClayton 3800VICAustralia ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton 3800VICAustralia Department of Chemistry University of WarwickGibbet Hill RoadCoventry CV47ALUK School of Life Sciences University of WarwickGibbet Hill CampusCoventry CV47ALUK Research School of Chemistry the Australian National UniversityActon 2601ACTAustralia Monash Proteomics and Metabolomics Facility Monash UniversityClayton 3800VICAustralia Institute of Pharmaceutical Sciences Albert-Ludwigs-Universitat Freiburg79104Germany

WS9326A is a peptide antibiotic containing a highly unusual N-methyl-E-2-3-dehydrotyrosine(NMet-Dht)residue that is incorporated during peptide assembly on a non-ribosomal peptide synthetase(NRPS).The cytochrome P450 encoded by sas16(P450Sas)has been shown to be essential for the formation of the alkene moiety in NMet-Dht,but the timing and mechanism of the P450Sas-mediatedα,β-dehydrogenation of Dht remained ***,we show that the substrate of P450Sas is the NRPS-associated peptidyl carrier protein(PCP)-bound dipeptide intermediate(Z)-2-pent-1′-*** demonstrate that P450Sas-mediated incorporation of the double bond follows N-methylation of the Tyr by the N-methyl transferase domain found within the NRPS,and further that P450Sas appears to be specific for substrates containing the(Z)-2-pent-1’-enyl-cinnamoyl group.A crystal structure of P450Sas reveals differences between P450Sas and other P450s involved in the modification of NRPS-associated substrates,including the substitution of the canonical active site alcohol residue with a phenylalanine(F250),which in turn is critical to P450Sas activity and WS9326A ***,our results suggest that P450Sas catalyses the direct dehydrogenation of the NRPS-bound dipeptide substrate,thus expanding the repertoire of P450 enzymes that can be used to produce biologically active peptides.

关键词： Cytochrome P450 Non-ribosomal peptide synthetase Protein crystal structure Enzyme mechanism Natural products Peptideantibiotic

Coastal blue carbon in China as a nature-based solution toward carbon neutrality

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The Innovation 2023年第5期4卷 109-123页

作者： Faming Wang Jihua Liu Guoming Qin jingfan zhang Jinge Zhou Jingtao Wu Lulu zhang Poonam Thapa Christian J.Sanders Isaac R.Santos Xiuzhen Li Guanghui Lin Qihao Weng Jianwu Tang Nianzhi Jiao Hai Ren Xiaoliang Research Station of Tropical Coastal Ecosystems Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystemsand the CAS Engineering Laboratory for Ecological Restoration of lsland and Coastal EcosystemsSouth China Botanical GardenChinese Academy of SciencesGuangzhou 510650China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 510650China Marine Research Institute Shandong UniversityQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China National Marine Science Centre Faculty of Science and EngineeringSouther Cross UniversityCoffs HarbourNSW 2450Australia Department of Marine Sciences University of Gothenburg41319 GothenburgSweden State Key Laboratory of Estuarine and Coastal Research and Instiute of Eco-Chongming East China Normal UniversityShanghai 201100China Key Laboratory for Earth System Modeling Ministry of EducationDepartment of Earth System ScienceTsinghua UniversityBejing 100084China Laboratory of Stable Isotope and Gulf Ecology Institute of Ocean EngineeringTsinghua's Shenzhen International Graduate SchoolShenzhen 518055China Department of Land Surveying and Geo-nformatics The Hong Kong Polytechnic UniversiyHongkong 99077China Innovative Research Center for Carbon Neutralization Global ONCE ProgramXiamen 361005China

To achieve the Paris Agreement,China pledged to become“Carbon Neutral”by the *** addition to massive decarbonization,this would require significant changes in ecosystems toward negative CO_(2)*** ability of coastal blue carbon ecosystems(BCEs),including mangrove,salt marsh,and seagrass meadows,to sequester large amounts of CO_(2)makes their conservation and restoration an important“nature-based solution(NbS)”for climate adaptation and *** this review,we examine how BCEs in China can contribute to climate *** the national scale,the BCEs in China store up to 118 Tg C across a total area of 1,440,377 ha,including over 75%as unvegetated tidal *** annual sedimental C burial of these BCEs reaches up to 2.06 Tg C year^(−1),of which most occurs in salt marshes and tidal *** lateral C flux of mangroves and salt marshes contributes to 1.17 Tg C year^(−1)along the Chinese *** and restoration of BCEs benefit climate change mitigation and provide other ecological services with a value of$32,000 ha^(−1)year^(−1).The potential practices and technologies that can be implemented in China to improve BCE C sequestration,including their constraints and feasibility,are also *** directions are suggested to improve blue carbon estimates on aerial extent,carbon stocks,sequestration,and mitigation *** and preserving BCEs would be a cost-effective step to achieve Carbon Neutral by 2060 in China despite various barriers that should be removed.

关键词： tidal coastal carbon

氧化石墨烯/次磷酸铝杂化物的制备及其对PC/ABS合金阻燃性能的改善

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北京化工大学学报（自然科学版） 2024年第5期51卷 46-53页

作者：张竞帆张胜赵景茂北京化工大学材料科学与工程学院北京100029

聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯(ABS)合金作为用量最大的塑料合金之一,在使用过程中其易燃性对人民的生命财产安全造成了严重的威胁,因此对其进行阻燃改性十分必要。通过自组装方法,制备了聚乙烯亚胺(PEI)接枝氧化石墨烯纳米片(PEI-... 详细信息

聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯(ABS)合金作为用量最大的塑料合金之一,在使用过程中其易燃性对人民的生命财产安全造成了严重的威胁,因此对其进行阻燃改性十分必要。通过自组装方法,制备了聚乙烯亚胺(PEI)接枝氧化石墨烯纳米片(PEI-GO)来修饰次磷酸铝(AHP)。制备的PEI-GO@AHP杂化物,作为PC/ABS(质量比为70/30)合金的阻燃剂。引入质量分数为8%的PEI-GO@AHP,可确保PC/ABS达到UL-94 V-0等级和29.1%的极限氧指数(LOI)。其最大热释放速率(PHRR)和总热释放量(THR)分别降低了41.0%和19.6%。本研究提供了一种简单而有效的方法来制备阻燃PC/ABS合金。

关键词：阻燃聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯(ABS)合金次磷酸铝(AHP)

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北京大兴国际机场指挥中心音视频系统创新实践

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交通企业管理 2020年第1期35卷 72-75页

作者：张竞帆北京大兴国际机场管理中心

北京大兴国际机场(以下简称“大兴机场”)一期工程计划到2025年实现年旅客吞吐量7200万人次、货邮吞吐量200万吨、飞机起降量62万架次的设计目标。为了实现这一宏伟蓝图,大兴机场统筹规划、敢于创新,构建起统一管理、协同操作、整合高... 详细信息

北京大兴国际机场(以下简称“大兴机场”)一期工程计划到2025年实现年旅客吞吐量7200万人次、货邮吞吐量200万吨、飞机起降量62万架次的设计目标。为了实现这一宏伟蓝图,大兴机场统筹规划、敢于创新,构建起统一管理、协同操作、整合高效的运行指挥机制;同时还建设了由多达68个业务信息系统组成的庞大的信息管理平台,为机场各个业务部门及相关单位提供实时、共享、统一、透明的应用服务。

关键词：机场管理音视频系统信息管理中心运行指挥中心北京大兴国际机场

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钼精矿回转窑自热焙烧新技术（英文）

稀有金属材料与工程 2015年第11期44卷 2618-2622页

作者：王连勇孙文强张井凡蔡九菊东北大学国家环境保护生态工业重点实验室辽宁沈阳110819 深圳市盛鑫源环保科技技术有限公司广东深圳518002

对钼精矿焙烧过程进行了热力学分析。结果表明,焙烧反应属于放热反应,反应一旦开始,在工业规模生产条件下完全可以自热进行。热分析实验表明,氧气浓度越高,越有利于钼精矿的转化率提高;物料粒度越小,越有利于焙烧反应完全程度的提高。... 详细信息

对钼精矿焙烧过程进行了热力学分析。结果表明,焙烧反应属于放热反应,反应一旦开始,在工业规模生产条件下完全可以自热进行。热分析实验表明,氧气浓度越高,越有利于钼精矿的转化率提高;物料粒度越小,越有利于焙烧反应完全程度的提高。对传统钼精矿焙烧回转窑的热平衡测试显示,煤作为外热源经燃烧后提供热量为4.42 GJ/t的烟气供入回转窑内,烟气中的氧浓度为10%。由于主反应区温度高,造成物料结块,阻碍了钼精矿的焙烧。本研究开发了钼精矿的自热焙烧新工艺,该工艺通过设置换热器回收主反应区放出的化学热,并将预热后的空气用于脱硫区的补热,提高了焙烧气的氧浓度。取消了传统回转窑的燃煤过程,整个焙烧过程仅靠6.45 GJ/t的化学反应热即可维持,没有含碳燃料的输入和CO_2的排放,其节能环保效益显著。

关键词：钼精矿自热焙烧回转窑节能

水电工程施工过程中的质量、安全、环境监控与信息收集

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水电与新能源 2015年第6期29卷 62-63,72页

作者：张竞帆湖北水总水利水电建设股份有限公司湖北武汉430034

介绍了在水电工程施工中,对工程质量、施工安全与环境的监控方法,包括施工信息资料的收集、影响因素的跟踪与识别、管理工作与施工过程的同步、统计分析与评价、制度管理等,强调了工程施工中过程管理和信息资料管理的重要性。

关键词：水电工程施工监控方法过程管理信息管理

统编教材下学科融合教学实践--以“比较古希腊哲学与中国先秦诸子学”一课为例

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现代基础教育研究 2021年第2期42卷 195-199页

作者：张静帆上海市南洋模范中学上海200032

统编三科教材全面推行背景下,学科之间交叉的部分越来越多,这让学科融合有了更高的可行性。文章以“比较古希腊哲学与中国先秦诸子学”一课为例,将思想政治学科与语文、历史、地理等学科相结合,进行教学实践,并提出了实现学科融合教学... 详细信息

统编三科教材全面推行背景下,学科之间交叉的部分越来越多,这让学科融合有了更高的可行性。文章以“比较古希腊哲学与中国先秦诸子学”一课为例,将思想政治学科与语文、历史、地理等学科相结合,进行教学实践,并提出了实现学科融合教学的路径:以学生问题为导向,合理设置教学目标;基于本学科主题,适当选择教学资源;利用活动课程,突出学生主体性;通过课堂实践,在运用中提升学生学科核心素养。

关键词：学科融合统编教材核心素养

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远程教育与英语教学

电子科技大学学报(社科版) 2001年第1期3卷 103-105页

作者：张锦帆电子科技大学!成都610054

远程英语教学涉及到教师、学生和科学家的通力合作。如何弥补面对面交流的损失 ?如何充分地利用远程教育的优势 ?如何处理远程教育中的教材及其它媒介的应用 ?许多问题都亟待人们去解决

关键词：远程教育市场需求教材现代技术