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Free-surface air entrainment in open-channel flows

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Science China(Technological Sciences) 2017年第6期60卷 893-901页

作者： WEI WangRu XU WeiLin DENG Jun tian zhong ZHANG FaXing State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

In hydraulic engineering,free-surface aeration is a natural phenomenon occurring in smooth channel *** self-aerated flows,a key aspect that has not yet been well understood is the formation mechanism of free-surface air *** this research,the process of free-surface entrapped deformation is analyzed theoretically and the critical radius of curvature for air entrainment is obtained,affected by flow mean velocity and *** the severity of local free-surface deformation exceeds the critical condition,the entrapped free surface encounters closure in the unstable deformation movement process,resulting in air *** inference agrees well with observed experimental results that are obtained from the processes of surface entrapped deformation and air entrainment captured by a high-speed camera-based data acquisition *** agreement indicates that self-aeration occurs in low-velocity open-channel *** is also confirmed that free-surface turbulent deformation provides a mechanism for air entrainment.

关键词： hydraulic engineering self-aeration turbulence free surface open-channel flows

Zero-inflated non-central negative binomial distribution

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Applied Mathematics(A Journal of Chinese Universities) 2022年第2期37卷 187-198页

作者： tian Wei-zhong LIU Ting-ting YANG Yao-ting College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118China School of Science Xi'an University of TechnologyXi'an 710054China

In this article, the zero-inflated non-central negative binomial(ZINNB) distribution is introduced. Some of its basic properties are obtained. In addition, we use the maximum likelihood estimation method to estimate t... 详细信息

关键词： zero-in ated non-central negative binomial distribution maximum likelihood estimation good-ness of fit

Climate change during the last glacial period on the southeast margin of Badain Jaran Desert, Northwest China

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Journal of Mountain Science 2019年第10期16卷 2379-2388页

作者： FAN Xiao-lu ZHANG Xin-yi tian Ming-zhong School of History Culture and Tourism Fuyang Normal UniversityFuyang 236037China School of the Earth Science and Resources China University of GeoscienceBeijing 100083China

Reconstruction of the desert paleoclimate is important to understand the mechanisms that triggered and/or enhanced climate *** optically stimulated luminescence(OSL)dating,grain size,magnetic susceptibility,X-ray powder diffraction(XRD)and geochemical indicators,we provide a welldated record of a sedimentary outcrop on the southeast margin of the Bardain Jaran Desert,Northwest China,during the last glacial *** Qz-OSL ages are obtained,41.0±3.4 ka,54.7±4.4 ka,59.5±5.0 ka and 66.8±5.8 ka,corresponding to the depths of 35 cm,70 cm,150 cm and 200 cm *** like grain size,clay content,magnetic susceptibility,XRD and geochemical index(***,Ba,Sr/Ca)jointly indicate abrupt climate changes at the depth of 35 cm(age,ca.41.0 ka)and200 cm(age,ca.67 ka).Namely,the 280 cm sedimentary outcrop perfectly records a warm wet climate stage,corresponding to the late Marine Isotope Stages(MIS)4 to the early MIS ***,there is a trend of grain size increase after around 40ka BP,which is most likely a signal of wind strength *** research supports that enhancing Siberian High pressure system during the late MIS 3played a key role in NW East Asia climate evolution.

关键词： Last glacial period Bardain Jaran Desert Climate change Siberian High pressure system XRD

The　physical　implication　of　coda　amplitude　ratio　and　its　possible　application

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 441-448页

作者： Zhang, tian-zhong Ma, Yun-Sheng Huang, Rong-Liang Institute of Geophysics China Seismological Bureau Beijing China

ＴｈｅｐｈｙｓｉｃａｌｉｍｐｌｉｃａｔｉｏｎｏｆｃｏｄａａｍｐｌｉｔｕｄｅｒａｔｉｏａｎｄｉｔｓｐｏｓｓｉｂｌｅａｐｐｌｉｃａｔｉｏｎＴＩＡＮ－ＺＨＯＮＧＺＨＡＮＧ（张天中）ＹＵＮ－ＳＨＥＮＧＭＡ（马支生）ＲＯＮＧ－... 详细信息

ＴｈｅｐｈｙｓｉｃａｌｉｍｐｌｉｃａｔｉｏｎｏｆｃｏｄａａｍｐｌｉｔｕｄｅｒａｔｉｏａｎｄｉｔｓｐｏｓｓｉｂｌｅａｐｐｌｉｃａｔｉｏｎＴＩＡＮ－ＺＨＯＮＧＺＨＡＮＧ（张天中）ＹＵＮ－ＳＨＥＮＧＭＡ（马支生）ＲＯＮＧ－ＬＩＡＮＧＨＵＡＮＧ（黄蓉良）Ｉｎ...

关键词： Coda amplitude ratio Coda Q Energy ratio Mean free path Seismic precursors

Information freshness optimization of multiple status update streams in Internet of things:Generation rate control and service rate reservation

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Digital Communications and Networks 2023年第4期9卷 971-980页

作者： tianci Zhang Junjie Zhou Zhengchuan Chen zhong tian Wanli Wen Yunjian Jia School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400044China National Mobile Communications Research Laboratory Southeast UniversityNanjingChina

The Internet of things(IoT)has become a key infrastructure providing up-to-date and fresh information for policy analysis and decision-making of upper-layer ***,there are limited sensing and communication resources in IoT devices,which significantly affects the timeliness and freshness of the updated *** work proposes two schemes,namely,the generation rate control and service rate reservation schemes,to improve the overall information freshness of multiple status update streams at the ***,using the recently proposed Age of Information(AoI)as the metric for evaluating information freshness,we characterized the overall information freshness,i.e.,the overall average AoI at the receiver for both schemes,by considering the urgency difference of status update and *** schemes for status updates and streams,respectively,were formulated as two optimization *** proved that both problems are convex and the optimal generation and service rates for different streams are found by the standard convex optimization ***,we proposed both approximate optimal generation and approximate optimal service rate for fast deployment in heavy and light load *** results verify the theoretical findings and accuracy of the proposed approximate solutions,guiding the design and deployment of IoT.

关键词： Internet of things Information freshness Age of information Multi-source M/M/1 queuing model

Surface reconstruction from unorganized point clouds based on edge growing

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Advances in Manufacturing 2019年第3期7卷 343-352页

作者： Xu-Jia Qin zhong-tian Hu Hong-Bo Zheng Mei-Yu Zhang College of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310023People's Republic of China Key Laboratory of Visual Media Intelligent Processing Technology of Zhejiang Province Hangzhou 310023People's Republic of China

Owing to unorganized point cloud data,unexpected triangles,such as holes and slits,may be generated during mesh surface *** solve this problem,a mesh surface reconstruction method based on edge growing from unorganized point clouds is *** method first constructs an octree structure for unorganized point cloud data,and determines the k-nearest neighbor for each ***,the method searches for flat areas in the point clouds to be used as the initial mesh edge growth regions,to avoid incorrect reconstruction of the mesh surface owing to the growth of initial sharp ***,the optimal mesh surface is obtained by controlling the mesh edge growing based on compulsive restriction and comprehensive optimization *** experimental results of mesh surface reconstruction show that the method is feasible and shows high reconstruction performance without introducing holes or slits in the reconstructed mesh surface.

关键词： Mesh surface reconstruction Point clouds Edge growing Octree

Identification of deregulated miRNAs and their targets in hepatitis B virus-associated hepatocellular carcinoma

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World Journal of Gastroenterology 2012年第38期18卷 5442-5453页

作者： Wen Wang Lan-.luan Zhao Hao Ren zhong-tian Qi De-partment of Microbiology Shanghai Key Laboratory of Medi-cal Biodefense Second Military Medical University Shanghai200433 China Laboratory of Signal Transduction Eastem Hepa-tobiliary-Surgery Hospital Second Military Medical UniversityShanghai 200433 China

AIM： TO identify the differentially expressed miRNAs and their targets in hepatitis B virus （HBV）-associated hepatocellular carcinoma （HCC）. METHODS： Six hundred and sixty seven human miRNAs were quantitatively analyzed by Taqman lowdensity miRNA array （TLDA） in HBV-HCC tissues. Gene ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway analyses were used to analyze the significant function and pathway of the differentially expressed miRNAs in HBV-HCC. TargetScan software was used to predict the targets of deregulated miRNAs. Western blotting and luciferase assay were performed to verify the targets of these ***： Ten up-regulated miRNAs （miR-217, miR- 518b, miR-517c, miR-520g, miR-519a, miR-522, miR- 518e, miR-525-3p, miR-512-3p, and miR-518a-3p） and 11 down-regulated miRNAs （miR-138, miR-214, miR-214#, miR-199a-5p, miR-433, miR-511, miR-592, miR-483-3p, miR-483-5p, miR-708 and miR-1275） were identified by Taqman miRNAs array and confirmed quantitatively by reverse transcription polymerase chain reaction in HCC and adjacent non-tumor tissues. GO and KEGG pathway analysis revealed that ＂regulation of actin cytoskeleton＂ and ＂pathway in cancer＂ are most likely to play critical roles in HCC tumorigenesis. MiR- 519a and ribosomal protein S6 kinase polypeptide 3 （RPS6KA3） were predicted as the most significant can-didates by miRNA-mRNA network. In addition, cyclin D3 （CCND3） and clathrin heavy chain （CHC）, usually up-regulated in HCC tissues, were validated as the di- rect target of miR-138 and miR-199a-5p, respectively.

关键词： Hepatocellular carcinoma miR-138 miR- 199a-5p Cyclin D3 Clathrin heavy chain Bioinformatics Taqman array

Mining Design Pattern Use Scenarios and Related Design Pattern Pairs:A Case Study on Online Posts

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Journal of Computer Science & Technology 2020年第5期35卷 963-978页

作者： Dong Liu Zhi-Lei Ren zhong-tian Long Guo-Jun Gao He Jiang School of Software Dalian University of TechnologyDalian 116024China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian 116000China DUT-RU International School of Information Science&Engineering at DUT Dalian University of Technology Dalian 116620China

In common design pattern collections,e.g.,design pattern books,design patterns are documented with templates that consist of multiple attributes,such as intent,structure,and sample *** adapt to modern developers,the depictions of design patterns,especially some specific attributes,should advance with the current programming technologies,for example,“known uses”,which exemplifies the use scenarios of design patterns in practice,and“related patterns”,which describes the relatedness between a design pattern and the others within a ***,it is not easy to update the contents of these attributes manually due to the diversity of the programming *** address this problem,in this work,we conducted a case study to mine design pattern use scenarios and related design pattern pairs from Stack Overflow posts to enrich the two *** first extracted the question posts relevant to each design pattern by identifying the design pattern ***,the topics of the posts were discovered by applying topic modeling ***,by analyzing the topics specified for each design pattern,we detected 195 design pattern use scenarios and 70 related design pattern pairs,involving 61 design patterns *** findings are associated with a variety of popular software frameworks and programming *** could complement the existing design pattern collections and help developers better acknowledge the usage and relatedness of design patterns in today's programming practice.

关键词： design pattern software documentation Stack Overflow topic model

Excitation of Internal Kink Mode by Circulating Supra-thermal Electrons

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Chinese Physics Letters 2012年第2期29卷 141-143页

作者： CHEN Shao-Yong WANG zhong-tian TANG Chang-Jian College of Physical Science and Technology Sichuan UniversityChengdu 610065 Southwestern Institute of Physics Chengdu 610041

The internal kink mode with a real frequency comparable with the bulk ion diamagnetic frequency is investigated in the case of lower hybrid wave *** is found that circulating supra-thermal electrons can directly destabilize the internal kink mode by resonance interaction in the neighborhood of the q =1 rational *** pressure gradient of circulating supra-thermal electrons on the resonance surface is crucial for excitation of the mode.

关键词： surface thermal neighborhood