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China Geology 2024年第4期7卷 801-802,811页

作者： Yu Yu xiao-liang Deng State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Keyuan Engineering Technical Test Center of Sichuan Province Chengdu 610091China

*** The Emeishan basalts is located in southwest China and northern Vietnam,covering an area of 2.5×10^(5) km^(2)(Zhong YT et al.,2014),which is the first widely recognized large igneous province(LIP)in China(Zhang ZS,2009).The Emeishan LIP has attracted a numbers of scholars for the reason that the LIP may play a significant role in the evolution of environment and *** JH et al.,(2018)pointed out that the weathering of the Emeishan basalts consumed carbon dioxide and caused a decrease in the climate of the early ***,the duration and termination of the Emeishan basalts eruption remain in *** paper reports a new discovery of tuffaceous in the middle part of the Upper Permian Wujiaping Formation from the northern margin of the Sichuan Basin,applying of LA-ICP-MS to obtain zircon U-Pb ages of tuffaceous and to constrain the lasted eruption timing of Emeishan LIP.

关键词： termination Upper eruption

Principal Model Analysis Based on Bagging PLS and PCA and Its Application in Financial Statement Fraud

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Journal of Systems Science and Information 2024年第2期12卷 212-228页

作者： xiao liang Qiwei XIE Chunyan LUO liang TANG Yi SUN School of Economics and Management Beijing University of TechnologyBeijing 100124China Shanghai Tongtu Semiconductor Technology Co. LtdShanghai 210203China School of Finance Anhui University of Finance&EconomicsBengbu 233000China

Motivated by the Bagging Partial Least Squares(Bagging PLS)and Principal Component Analysis(PCA)algorithms,a novel approach known as Principal Model Analysis(PMA)method is introduced in this *** the proposed PMA algorithm,the PCA and the Bagging PLS are *** this method,multiple PLS models are trained on sub-training sets,derived from the training set using the random sampling with replacement *** regression coefficients of all the sub-PLS models are fused in a joint regression coefficient *** final projection direction is then estimated by performing the PCA on the joint regression coefficient ***,the proposed PMA method is compared with other traditional dimension reduction methods,such as PLS,Bagging PLS,Linear discriminant analysis(LDA)and *** results on six public datasets demonstrate that our proposed method consistently outperforms other approaches in terms of classification performance and exhibits greater ***,it is employed in the application of financial statement fraud *** and other five algorithms are utilized to financial statement fraud which concerned by the academic community,and the results indicate that the classification of PMA surpassed that of the other methods.

关键词： principal model analysis partial least squares principal component analysis dimension reduction ensemble learning financial statement fraud detection

Epidemic Spread in Networks Induced by Deactivation Mechanism

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Communications in Theoretical Physics 2008年第5期49卷 1357-1360页

作者： YU xiao-Ling WU xiao ZHANG Duan-Ming LI Zhi-Hao liang Fang WANG xiao-Yu Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We have studied the topology and epidemic spreading behaviors on the networks in which deactivation mechanism and long-rang connection are coexisted. By means of numerical simulation, we find that the clustering coefficient C and the Pearson correlation coefficient r decrease with increasing long-range connection μ and the topological state of the network changes into that of BA model at the end （when μ = 1）. For the Susceptible-Infect-Susceptible model of epidemics, the epidemic threshold can reach maximum value at μ = 0.4 and presents two different variable states around μ= 0.4.

关键词： epidemic threshold deactivation mechanism long-rang connection

Reinforcement learning based energy-efficient internet-of-things video transmission

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Intelligent and Converged Networks 2020年第3期1卷 258-270页

作者： Yilin xiao Guohang Niu liang xiao Yuzhen Ding Sicong Liu Yexian Fan Department of Information and Communication Engineering Xiamen UniversityXiamen 361005China College of Information and Mechanical and Electrical Engineering Ningde Normal UniversityNingde 352100China

The video transmission in the Internet-of-Things(IoT)system must guarantee the video quality and reduce the packet loss rate and the delay with limited resources to satisfy the requirement of multimedia *** this paper,we propose a reinforcement learning based energy-efficient IoT video transmission scheme that protects against interference,in which the base station controls the transmission action of the IoT device including the encoding rate,the modulation and coding scheme,and the transmit power.A reinforcement learning algorithm state-action-reward-state-action is applied to choose the transmission action based on the observed state(the queue length of the buffer,the channel gain,the previous bit error rate,and the previous packet loss rate)without knowledge of the transmission channel model at the transmitter and the *** also propose a deep reinforcement learning based energy-efficient IoT video transmission scheme that uses a deep neural network to approximate Q value to further accelerate the learning process involved in choosing the optimal transmission action and improve the video transmission ***,both the performance bounds of the proposed schemes and the computational complexity are theoretically *** results show that the proposed schemes can increase the peak signal-to-noise ratio and decrease the packet loss rate,the delay,and the energy consumption relative to the benchmark scheme.

关键词： Internet-of-Things(IoT) video transmission reinforcement learning energy efficiency

Growth and Interface Structure of Mn on InP (001)

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Chinese Physics Letters 1998年第10期15卷 730-731页

作者： DONG Guo-sheng CHEN Yan SHEN xiao-liang JIN xiao-feng Laboratory of Surface Physics Fudan UniversityShanghai 200433 Analysis and Measurement Center Fudan UniversityShanghai 200433

An attempt to grow single crystalline thin films of body-centered-cubic(bcc)Mn on InP(001)has been carried out by molecular beam *** situ reflection high energy electron diffraction and ex situ x-ray diffraction are used to characterize the film and interface *** is found that the metastable phase of bcc Mn fails to stabilize on the substrate despite of their perfect *** result suggests again the importance of interface structure in the epitaxy of 3d metals on semiconductors.

关键词： interface cubic perfect

The Reductive Addition Reaction of Substituted 2-Chloromethyl-1,3,4-oxadiazole to Aldehydes and Ketones Promoted by Samarium Diiodide

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Chinese Chemical Letters 2005年第12期16卷 1566-1568页

作者： xiao liang XU Wei Min ZHU Yong Min ZHANG Department of Chemistry Zhejiang University Xixi Campus Hangzhou 310028 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

1-（β-Hydroxyalkyl）-l,3,4-oxadiazole derivatives were synthesized via reductive addition reactions of 2-chloromethyl-l,3,4-oxadiazole with carbonyl compounds under mild conditions promoted by SmI2.

关键词： Reductive addition samarium diiodide 1-(β-hydroxyalkyl)-1 3 4-oxadiazole deriva-tives synthesize

Optimal distributed power allocation for a new spectrum sharing paradigm in cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 37-43页

作者： ZHANG xiao-liang JI Hong LI Xi DAI Li-yun Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Beijing 100876 China School of Software and Communication Engineering Jiangxi University of Finance and Economics Nanchang 330013 China

The problem of power allocation in cognitive radio networks plays an important role to improve the efficiency of spectrum utilization. However, most of previous works focus on the power allocation for secondary users in spectrum sharing overlay or spectrum sharing underlay, which needs to frequently handoff between the idle spectrum bands or considers the interference constraints in all spectrum bands respectively. In order to reduce the handoff and fully utilize the spectrum resource, we propose a new spectrum sharing paradigm which not only can just need to adjust the transmit power in spectrum bands instead of frequently handoff between idle spectrum bands, but can fully utilize the spectrum resource as we only consider the interference power constraints in active spectrum bands rather than in all spectrum bands. Then based on this new spectrum sharing paradigm and the constraint conditions, we study the distributed power allocation for secondary users and formulate the optimization problem as a non-cooperative game problem, after that the variational inequality approach is used to solve this game problem and a Nash equilibria solution is got, finally simulation results are illustrated to demonstrate the performance of the proposed scheme.

关键词： resource allocation efficiency handoff spectrum sharing paradigm

Edge Intelligence for 6G Networks

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China Communications 2022年第8期19卷 I0003-I0005页

作者： Haifeng Zheng Lin Gao Zhiyong Chen liang xiao the College of Physics and Information Engineering Fuzhou UniversityChina the School of Electronics and Information Engineering Harbin Institute of TechnologyShenzhenChina the Cooperative Medianet Innovation Center Shanghai Jiao Tong University(SJTU)ShanghaiChina the Department of Information and Communication Engineering Xiamen UniversityXiamenChina

With the rapid development of smart terminals and infrastructures,as well as diversified applications(e.g.,autonomous driving,virtual and augmented reality,space-air-ground integrated networks)with colorful demands,current networks(e.g.,4G and 5G networks)may not be well suited to the requirements of novel applications and ***,efforts from both the industry and academia have been made on the research into 6G networks,artificial intelligence(AI)will play a pivotal role in the design and optimization of 6G networks.

关键词： networks driving smart

Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science China Earth Sciences 2011年第4期54卷 493-508页

作者： xiao liang SUN BaiNian LI XiangChuan REN WenXiu JIA Hui Key Laboratory of Western China's Environmental Systems of the Ministry of Education and College of Earth and Environment Science Lanzhou University Lanzhou 730000 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China College of Arts and Sciences Bryant University Smithfield RI 02917 U.S.A. Key Laboratory of Western China's Mineral Resources and Geological Engineering of Ministry of Education Chang'an University Xi'an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambarformosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

Adsorption of boron and its relationship with morphologies of TiC

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Rare Metals 2016年第9期35卷 705-710页

作者： Hai-Min Ding xiao-liang Fan Xin-Chun Zhang Ze-You Zheng School of Energy Power and Mechanical Engineering North China Electric Power University

First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti *** is found that although the adsorption of boron on all the low-index Ti C crystal planes is thermally favorable,it will be adsorbed more easily by C-terminated {111} and {011} planes,while less possible to be adsorbed by {001}.The study of the formation of B–B clusters indicates that the distribution of boron adatoms on C-terminated（111） and {011} planes will be more uniform,and the diffusion of the adatom further confirms the above *** to the geometry relationship and growth rate of different crystal planes,it is deduced that the adsorption of boron on Ti C will seriously impede the growth of {111} and {011} planes,which can make Ti C grow into hexagonal platelets.

关键词： Ti C Adsorption Surfaces and interfaces First-principle calculations