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Resource Search in Unstructured Peer-to-Peer System Based on Multiple-Tree Overlay Structure

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Wuhan University Journal of Natural Sciences 2007年第5期12卷 887-892页

作者： YU Jianqiao liao Jianwei College of Computer and Information Science Southwest University Chongqing 400715 China

We propose a multiple-tree overlay structure for resource discovery in unstructured P2P systems. Peers that have similar interests or hold similar type of resources will be grouped into a tree-like cluster. We exploit the heterogeneity of peers in each cluster by connecting peers with more capacities closer to the root of the tree. The capacity of a peer can be defined in different ways （e.g. higher network bandwidth, larger disk space, more data items of a certain type etc.） according to different needs of users or applications.

关键词： unstructured P2P system tree-like cluster similar interest

The Influence of Water Level Change in Slope Stability of Earth Dam

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上海交通大学学报 2004年第z2期38卷 217-222页

作者： xiao zheng-hua Han Bo liao Hong-jian Gao xiao-yu Department of Civil Engineering Xi''an Jiaotong University Xi''an710049 China College of Architectural Engineering Xinjiang University Urumqi830008 China Department of Civil Engineering Xi''an Jiaotong University Xi''an710049 China Department of Civil Engineering Xi''an Jiaotong University Xi''an710049 China Department of Civil Engineering Xi''an Jiaotong University Xi''an710049 China

The analysis of seepage flow and slope stability to earth dam in water level change is performed. FEM is used to analyzing the influence of percolation and the results including the pore water head of any point, seepage discharge and so on are obtained. The method of slices is introduced to calculating the slope stability of the earth dam. Through an example it is separately discussed the influence of seepage flow when water level is changed in earth dam slope and the effects of percolation in the stability of the earth dam slope. Some helpful conclusions are *** can be making the best of the tow methods and the results can be used in engineering for reference.

关键词： seepage flow stability factor FEM the method of Bishop

Extraordinary hot extreme in summer 2022 over the Yangtze River basin modulated by the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： zhen liao Yu-Feng YUAN Yang CHEN Pan-Mao zHAI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the Yangtze River basin in summer 2022,with 300 sites established new temperature records and nearly 96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by an extremely strong and westward-shifted western Pacific subtropical high(WPSH).The global warming effect contributed primarily to the abnormal hot days in the Yangtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analysis indicates that anthropogenic warming may increase the probability of such extensively persistent hot extremeby1.8 times.

关键词： Hot extreme The Yangtze River basin Global warming Tropical Pacific forcing

Synthesis and Structure of N-(E)-Enoyl(-)-bornane-10,2-sultams

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Chemical Research in Chinese Universities 2001年第1期17卷 56-62页

作者： LI Yan CHEN liao rong zHOU zhong qiang HUANG Jin xia Faculty of Chemistry and Material Science Hubei UniversityWuhan 430062P.R.China Analysis and Testing Center Wuhan UniversityWuhan 430072P.R.China Department of Bioengineering Huazhong University of Scence and TechnologyWuhan 430074P.R.China

Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction analysis. The crystal of C 16 O 3SNH 25 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 734 6(7) nm, b =1 142 7(3) nm, c =2 009 7(3) nm, β =90 00°, V =1 686 9 nm 3, z=4, D c=1 250 g/cm 3, μ =1 926 cm -1 and F (000)=672. The crystal of C 15 O 3SNH 23 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 738 2(2) nm, b =0 921 6(1) nm, c =2 280 9(8) nm, β =90 00°, V =1 551 7 nm 3, z =4, D c=1 273 g/cm 3, μ =2 504 cm -1 and F (000)=640. The structural characteristics with respect to the potential utility for the stereoselective Michael addition reaction of the N enoyl group are discussed.

关键词： N (E ) Enoyl(-) bornane 10 2 sultam Crystal structure Michael addition

On the Unitriangular Groups over Rational Numbers Field

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Acta Mathematica Sinica,English Series 2022年第4期38卷 718-734页

作者： Rui GAO Jun liao He Guo LIU xing zhong xU School of Mathematics and Statistics Hubei UniversityWuhan 430062P.R.China

Let U(n,Q)be the group of all n×n(upper)unitriangular matrices over rational numbers field *** S be a subset of U(n,Q).In this paper,we prove that S is a subgroup of U(n,Q)if and only if the(i,j)-th entry S;satisfies some condition(see Theorem 3.5).Furthermore,we compute the upper central series and the lower central series for S,and obtain the condition that the upper central series and the lower central series of S coincide.

关键词： Nilpotent groups unitriangular groups central series

P2_(1)2_(1)2_(1)-C16: An ultrawide bandgap and ultrahard carbon allotrope with the bandgap larger than diamond

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Frontiers of physics 2022年第6期17卷 71-78页

作者： Mingqing liao Jumahan Maimaitimusha xueting zhang Jingchuan zhu Fengjiang Wang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Ultrawide bandgap semiconductor,e.g.,diamond,is considered as the next generation of ***,a new orthorhombic carbon allotrope(P2_(1)2_(1)2_(1)-C16)with ultrawide bandgap and ultra-large hardness is *** stability of the newly designed carbon is confirmed by the energy,phonon spectrum,ab-initio molecular dynamics and elastic *** hardness ranges from 88 GPa to 93 GPa according to different models,which is comparable to *** indirect bandgap reaches 6.23 eV,which is obviously larger than that of diamond,and makes it a promising ultra-wide bandgap ***,the experimental possibility is confirmed by comparing the simulated x-ray diffraction with experimental results,and two hypothetical transformation paths to synthesize it from graphite are proposed.

关键词： carbon allotrope ultrawide bandgap semiconductor ultrahard first-principles

Performance of N95 elastomeric respirators in high humidity and high coal dust concentration environment

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International Journal of Mining Science and Technology 2022年第1期32卷 215-224页

作者： Jintuo zhu xinjian He Liang Wang xiaoxue liao Guangping Teng Pengli Jing Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology School of Safety EngineeringChina University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

High humidity and high dust concentration in deep coal mines may severely challenge the performance of respirators worn by coal *** paper aims at quantitatively evaluating the respirators used in deep coal mines and providing scientific guidance for the respiratory protection of *** on the self-designed in-situ PM2.5 collector,controllable PM2.5 generator,human breathing simulator,and respirator simulation testing system,under the simulated deep mine working condition,this study investigated the effects of dust loading,wearing time,and dust concentration on the filtration efficiency,breathing resistance,and quality factor of N95 elastomeric *** the increase of dust loading,the respirator filtration efficiency firstly decreased,then increased(minimum value 97.5%).The breathing resistance increased exponentially from 120 to 180 to 1020-1530 Pa,and the quality factor decreased logarithmically from 0.051 to 0.076 to 0.0058-0.0085 Pa^(-1).As the PM2.5 coal dust concentration increased from 5 to 50 mg/m^(3),the wearing time for the respirator breathing resistance to exceed 300 Pa reduced from 7 h to less than 1 *** N95 elastomeric respirator is not able to perform an 8-h work *** avoid the excessive breathing resistance caused by dust loading,more filter cartridges are needed for coal miners.

关键词： Coal dust Respirator Dust loading Filtration efficiency Breathing resistance

Improving Ultrasonic Testing by Using Machine Learning Framework Based on Model Interpretation Strategy

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 174-186页

作者： Siqi Shi Shijie Jin Donghui zhang Jingyu liao Dongxin Fu Li Lin NDT&E Laboratory Dalian University of TechnologyDalian 116024China China Nuclear Industry 23 Construction Co. Ltd.Beijing 101300China

Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying *** signifcant features from UT data is essential for efcient defect ***,the hidden physics behind ML is unexplained,reducing the generalization capability and versatility of ML methods in *** this paper,a generally applicable ML framework based on the model interpretation strategy is proposed to improve the detection accuracy and computational efciency of ***,multi-domain features are extracted from the UT signals with signal processing techniques to construct an initial feature ***,a feature selection method based on model interpretable strategy(FS-MIS)is innovatively developed by integrating Shapley additive explanation(SHAP),flter method,embedded method and wrapper *** most efective ML model and the optimal feature subset with better correlation to the target defects are determined *** proposed framework is validated by identifying and locating side-drilled holes(SDHs)with 0.5λcentral distance and different *** ultrasonic array probe is adopted to acquire FMC datasets from several aluminum alloy specimens containing two SDHs by *** optimal feature subset selected by FS-MIS is set as the input of the chosen ML model to train and predict the times of arrival(ToAs)of the scattered waves emitted by adjacent *** experimental results demonstrate that the relative errors of the predicted ToAs are all below 3.67%with an average error of 0.25%,signifcantly improving the time resolution of UT *** this basis,the predicted ToAs are assigned to the corresponding original signals for decoupling overlapped pulse-echoes and reconstructing high-resolution FMC *** imaging resolution is enhanced to 0.5λby implementing the total focusing method(TFM).The relative errors of hole depths and central distance are no more than 0.51%and 3.57%,***

关键词： Ultrasonic testing Machine learning Feature extraction Feature selection Shapley additive explanation

On the Connectivity of One-dimensional Vehicular Ad Hoc Networks

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China Communications 2010年第2期7卷 65-70页

作者： liao Jianxin Li Yuanzhen Li Tonghong zhu xiaomin zhang Lei State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China EBUPT Information Technology Co. Ltd Beijing 100083 China Technical University of Madrid Madrid Spain 28660

In this paper we analyze connectivity of one-dimensional Vehicular Ad Hoc Networks where vehicle gap distribution can be approximat- ed by an exponential distribution. The probabilities of Vehicular Ad Hoc Network connectivity for difference cases are derived. Furthermore we proof that the nodes in a sub-interval [z1, z1 ＋ △z] of interval [0,z],z 〉 0 where all the nodes are independently uniform distributed is a Poisson process and the relationship of Vehicle Ad hoc Networks and one-dimensional Ad Hoc networks where nodes independently uniform distributed in [zl, z1 ＋ △z] is explained. The analysis is validated by computing the probability of network connectivity and comparing it with the Mont Carlo simu- lation results.

关键词： Intelligent Transportation Systems (ITS) connectivity Vehicular Ad Hoc Networks onedimensional Ad Hoc Networks