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Characteristics of bioaerosols under high-ozone periods,haze episodes,dust storms,and normal days in Xi'an,China

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Particuology 2024年第7期90卷 140-148页

作者： yiming yang Liu yang Xiaoyan Hu Zhenxing Shen Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an710049China Key Lab of Aerosol Chemistry&Physics SKLLQGInstitute of Earth EnvironmentChinese Academy of SciencesXi’an710049China

The characteristics of bioaerosols and their effects on human beings'health have become a major public concern in the recent *** study compared the characteristics of bioaerosols under different types of pollution(high-ozone[HO]episodes,haze episodes,and dust storms[DSs]),with those of bioaerosols on normal days(NDs)in Xi'an,*** concentrations,diurnal variations,and size distribution of bacteria,fungi,and total airborne microbes(TAMs)were *** results showed that the bacterial and fungal concentrations were the highest during DSs and on NDs,reaching 425.2 and 956.9 colony-forming units/m^(3),*** concentration of TAMs was the highest during HO episodes,reaching 10.7×10^(6)cells/m^(3),which was significantly higher than that during the other *** maximum concentrations of bacteria and fungi during HO episodes were observed in the morning,while they appeared separately in the morning and evening during haze *** and TAMs during DSs reached peak concentrations in the morning and evening,which is opposite to the particulate matter(PM)distribution *** NDs,temperature and relative humidity had significant effects on *** size distributions of airborne bacteria exhibited bimodal patterns,whereas unimodal distributions were observed for *** mainly attached in fine particles(<2.1μm)with proportions of 67.4%and 60.5%during haze episodes and DSs,respectively,which means that fungi were easily penetrated into the human respiratory *** evaluation of influence factors revealed that PM_(2.5) and PM10 had negative effects on fungal concentration during DSs,and ozone concentration and temperature were inversely correlated with fungal concentration during HO *** results provide valuable reference data for elucidating the formation and evolution of bioaerosols under different types of pollution.

关键词： Bacteria Fungi Total airborne microbe Different air pollution types Influence factors

Chalcogen Effect of Atom Substitution on the Properties of Tris(2,4,6-trichlorophenyl)methyl(TTM)Radical

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Chemical Research in Chinese Universities 2023年第2期39卷 197-201页

作者： yang yiming QIU Lili SHI Xueliang Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai200062P.R.China

Luminescent open-shell organic radicals have recently been regarded as one of the most potential materials in organic light-emitting diodes(OLEDs).Herein,we have synthesized two new organic radicals,namely tris{4-[4-(tert-butyl)phenoxy]-2,6-dichlorophenyl}methane radical(TTM-O)and tris(4-{[4-(tert-butyl)-phenyl]thio}-2,6-dichlorophenyl)methane radical(TTM-S),by the substitution of chalcogen atom elements at the para position of conventional tris(2,4,6-trichlorophenyl)methyl(TTM)radical ***,both TTM-O and TTM-S exhibited significantly enhanced photostability compared with the unsubstituted TTM radical ***,the chalcogen atom also had a crucial impact on the photoluminescence quantum yield(PLQY)of the radicals,i.e.,the PLQY of TTM-S was greatly enhanced compared to TTM radical while TTM-O was nearly ***,TTM-S showed intense PLQY of 37.54%and 185-fold longer photostability than that in cyclohexane solution of TTM.

关键词： Luminescent organic radical Chalcogen atom effect Photoluminescence quantum yield(PLQY)

Researching on quadrature conversion structures For an UWB demonstrative receiver

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Journal of Systems Engineering and Electronics 2006年第4期17卷 875-882页

作者： Zhu Canyan Wang yiming yang Huibao Liu Jiasheng School of Electronics and Information Engineering Sonchow Univ. Suzhou 215021 P.R.China

Some structures of digital quadrature AD conversion for soft-ware-defined radio （SDR） systems are studied. Their performances and affections on the SDR systems are also analyzed. Two generalized quadrature AD schemes are proposed. In one of them, the AD sampling speed can be reduced by 2 times; and in the other both the output data rate of every channel and AD sampling speed can be lowered by paralleling the digital quadrature filtering structure. These structures can be also easily implemented into modules, and the polyphase filters can be flexibly realized by VHDL language based one chip of FPGA. To assess the proposed schemes, their applications to a particular ultra wideband （UWB） demonstrative receiver system are introduced. Some experimental results are also given. It is shown that the generalized quadrature AD structures are reliable and feasible for its module design, and performances are improved obviously for its better performance to price ratio.

关键词： software defined radio (SDR). digital auadrature sonversion nolvohase filtering ultra wideband (UWB)

Quantitative Method of Classification and Discrimination of a Porous Carbonate Reservoir Integrating K-means Clustering and Bayesian Theory

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 176-189页

作者： FANG Xinxin ZHU Guotao yang yiming LI Fengling FENG Hong China Coal Research Institute Beijing 100013China Xi'an Research Institute of China Coal Research Institute Xi’an 710077China Oilfield Technology Service Company of Xinjiang Oilfield Company PetroChinaKaramayXinjiang 834000China

Reservoir classification is a key link in reservoir ***,traditional manual means are inefficient,subjective,and classification standards are not ***,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination *** methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are *** results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core *** discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging *** the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir.

关键词： upstream resource exploration reservoir classification carbonate K-means clustering Bayesian discrimination Cenomanian-Turonian Iraq

BDSec:Security Authentication Protocol for BeiDou-Ⅱ Civil Navigation Message

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China Communications 2024年第6期21卷 206-218页

作者： Wu Zhijun Zhang Yuan yang yiming Wang Peng Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay *** solve this problem,we present a security authentication protocol,called as BDSec,which is designed by using China’s cryptography Shangyong Mima(SM) series algorithms,such as SM2/4/9 and Zu Chongzhi(ZUC)*** BDSec protocol,both of BDⅡ-CNAV and signature information are encrypted using the SM4 algorithm(Symmetric encryption mechanism).The encrypted result is used as the subject authentication *** protocol applies SM9 algorithm(Identity-based cryptography mechanism) to protect the integrity of the BDⅡ-CNAV,adopts the SM2 algorithm(Public key cryptosystem) to guarantee the confidentiality of the important session information,and uses the ZUC algorithm(Encryption and integrity algorithm) to verify the integrity of the message authentication serial number and initial information and the information in authentication initialization sub-protocol *** results of the SVO logic reasoning and performance analysis show that BDSec protocol meets security requirements for the dual user identity authentication in BDS and can realize the security authentication of BDⅡ-CNAV.

关键词： BDII civil navigation messages(BDIICNAV) BeiDou navigation satellite system(BDS) identity-based cryptography mechanism navigation message authentication protocol(BDSec)

Hybrid model-driven and data-driven method for predicting concrete creep considering uncertainty quantification

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Frontiers of Structural and Civil Engineering 2024年第10期18卷 1524-1539页

作者： yiming yang Chengkun ZHOU Jianxin PENG Chunsheng CAI Huang TANG Jianren ZHANG School of Civil Engineering Hunan City UniversityYiyang 413000China Hunan Engineering Research Center of Development and Application of Ceramsite Concrete Technology Hunan City UniversityYiyang 413000China School of Civil Engineering Changsha University of Science and TechnologyChangsha 410114China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing 211189China Department of Civil and Environmental Engineering Louisiana State UniversityBaton RougeLA 70803USA

Reasonable prediction of concrete creep is the basis of studying long-term deflection of concrete *** this paper,a hybrid model-driven and data-driven(HMD)method for predicting concrete creep is proposed by using the sequence integration ***,a novel uncertainty prediction model(UPM)is developed considering uncertainty ***,the effectiveness of the proposed method is validated by using the North-western University(NU)database of creep,and the effect of uncertainty on prediction results are also *** analysis results show that the proposed HMD method outperforms the model-driven and three data-driven methods,including the genetic algorithm-back propagation neural network(GA-BPNN),particle swarm optimization-support vector regression(PSO-SVR)and convolutional neural network only method,in accuracy and time *** proposed UPM of concrete creep not only ensures relatively good prediction accuracy,but also quantifies the model and measurement uncertainties during the prediction ***,although incorporating measurement uncertainty into concrete creep prediction can improve the prediction performance of UPM,the prediction interval of the creep compliance is more sensitive to model uncertainty than to measurement uncertainty,and the mean contribution of variance attributed to the model uncertainty to the total variance is about 90%.

关键词： concrete creep uncertainty prediction hybrid method data-driven model-driven convolutional neural network

Interaction between Cd and Pb in the soil-plant system: a case study of an arid oasis soil-cole system

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Journal of Arid Land 2014年第1期6卷 59-68页

作者： ZhuanJun ZHAO ZhongRen NAN ZhaoWei WANG yiming yang Masayuki SHIMIZU College of Resource & Environment Lanzhou University Department of Soil and Crop Science Colorado State University

The Hexi Corridor,our study area,is located in Northwest China and is also the most developed area of oasis farming in arid regions of Northwestern ***,the rapid development of metallurgy and chemical industries in this region poses a great threat to the accumulation of heavy metals in *** objectives of this study are(1)to determine the influence of heavy metals on plant growth;(2)to assess the translocation capability of heavy metals in soil-plant system;and(3)to investigate the interaction between heavy *** experiments were conducted on cole(Brassica campestris L.)grown in the arid oasis soils singly and jointly treated with cadmium(Cd)and lead(Pb).Nine treatments were applied into the *** the same planting conditions,three scenarios of Cd,Pb and Cd–Pb were designed to compare the interaction between Cd and *** results showed that the response of cole weights to Cd,Pb and Cd–Pb treatments was slight,while Cd and Pb uptakes in cole were more sensitive to the single effects of Cd and Pb concentration in soils from the lower treatment *** the influence of the single Cd,Pb and joint Cd–Pb treatments,Cd concentrations were lower in the cole roots than in the shoots,while for Pb,the results were *** studies revealed that the interaction of Cd and Pb could weaken the cole’s ability to uptake,concentrate and translocate heavy metals in arid oasis soils.

关键词： heavy metals interaction vegetables oasis soils arid regions Brassica campestris L.

Chemical fractionations and bioavailability of cadmium and zinc to cole (Brassica campestris L.) grown in the multi-metals contaminated oasis soil,northwest of China

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Journal of Environmental Sciences 2011年第2期23卷 275-281页

作者： yiming yang Zhongren Nan Zhuanjun Zhao Shengli Wang Zhaowei Wang Xia Wang Key Laboratory of Western China' s Environmental System Ministry of Education College of Resource and Environment Lanzhou University Lanzhou 730000 China School of Chemical Engineering North West University for Nationalities Lanzhou 730030 China

A pot experiment was conducted to study the relationship between distribution of cadmium （Cd） and zinc （Zn） and their availability. to cole （Brassica campestris L.） grown in the multi-metal contaminated oasis soil in northwest of China. The results showed that Cd and Zn in the unpolluted oasis soil was mainly found in the residual fractionation, however, with increasing contents of Cd and Zn in the oasis soil, the distribution of Cd and Zn changed significantly. The growth of cole could be promoted by low Cd and Zn concentration, but significantly restrained by high concentrations. There was antagonistic effect among Cd and Zn in the multi-metals contaminated oasis soil. Stepwise regression analysis between fractionations distribution coefficients of the two meals in the soil and their contents in cole showed that both Cd and Zn in the exchangeable fractionation in the oasis soil made the most contribution on the uptake of Cd and Zn in cole. The bio-concentration factor （BCF） of Cd was greater than Zn in cole, and BCFs of the two metals in leaves were greater than those in roots. The translocation factors of the two metals in cole were greater than 1, and the two metals mainly accumulated in the edible parts in cole. Therefore, cole is not a suitable vegetable for the oasis soil because of the plants notable contamination by heavy metals.

关键词： fractionation bioavailability cadmium and zinc cole oasis soil

Enhancing Multi-agent Coordination via Dual-channel Consensus

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Machine Intelligence Research 2024年第2期21卷 349-368页

作者： Qingyang Zhang Kaishen Wang Jingqing Ruan yiming yang Dengpeng Xing Bo Xu Institute of Automation Chinese Academy of SciencesBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Successful coordination in multi-agent systems requires agents to achieve *** works propose methods through information sharing,such as explicit information sharing via communication protocols or exchanging information implicitly via behavior ***,these methods may fail in the absence of communication channels or due to biased *** this work,we propose to develop dual-channel consensus(DuCC)via contrastive representation learning for fully cooperative multi-agent systems,which does not need explicit communication and avoids biased *** comprises two types of consensus:temporally extended consensus within each agent(inner-agent consensus)and mutual consensus across agents(inter-agent consensus).To achieve DuCC,we design two objectives to learn representations of slow environmental features for inner-agent consensus and to realize cognitive consistency as inter-agent *** DuCC is highly general and can be flexibly combined with various MARL *** extensive experiments on StarCraft multi-agent challenge and Google research football demonstrate that our method efficiently reaches consensus and performs superiorly to state-of-the-art MARL algorithms.

关键词： Multi-agent reinforcement learning contrastive representation learning consensus multi-agent cooperation cognitive consistency