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A Methodology for Identifying Defects in Wire Rope Based on Permanent Magnet Excitation

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第3期34卷 296-301页

作者： Guo Ruipeng wang Haitao ge Suijia College of Automation Engineering Nanjing University of Aeronautics and Astronautics

A wire rope defects detection method based on permanent magnet excitation is proposed.A detection system,mainly composed of permanent magnet excitation,distance detection,multi-sensor magnetic flux leakage signal acquisition and data analysis device,is set *** to the different characteristics of the multi-sensor magnetic flux leakage signal,the localized fault(LF)and loss of metallic cross-sectional area(LMA)signal is separated,and then the two defects can be *** experiments show that the method can effectively detect the two defects when they appear simultaneously on the wire rope.

关键词： permanent magnet excitation leakage defects localized separated metallic broken preprocessing

Comparison of tailpipe carbonyls and volatile organic compounds emissions from in-use gasoline/CNG bi-fuel vehicles

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Journal of Environmental Sciences 2024年第1期135卷 619-629页

作者： Jiachen Li Yunshan ge Xin wang Mengzhu Zhang Haohao wang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its *** exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone *** this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were *** is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or *** to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated *** a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,*** contributed to over 90%of the total OFP of the *** terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.

关键词： CNG Gasoline Carbonyls VOCs OFP

Steady-state relation of a two-level system strongly coupled to a many-body quantum chaotic environment

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Communications in Theoretical Physics 2023年第2期75卷 56-59页

作者： Hua Yan Jiaozi wang Wen-ge wang Department of Modern Physics University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Microscale Magnetic Resonance University of Science and Technology of ChinaHefei 230026China Department of Physics University of OsnabrückD-49076 OsnabrückGermany

We study the long-time average of the reduced density matrix(RDM)of a two-level system as the central system,which is locally coupled to a many-body quantum chaotic system as the environment,under an overall Schr?dinger evolution.A phenomenological relation among elements of the RDM is proposed for a dissipative interaction in the strong coupling regime and is tested numerically with the environment as a defect Ising chain,as well as a mixed-field Ising chain.

关键词： steady-state relations eigenstate thermalization hypothesis quantum chaos two-level system

The spatiotemporal characteristics of spring phenophase changes of Fraxinus chinensis in China from 1952 to 2007

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Science China Earth Sciences 2012年第6期55卷 991-1000页

作者： wang HuanJiong DAI JunHu ge QuanSheng Institute of geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

We selected widely distributed and well observed plant species Fraxinus chinensis to study the formation mechanism of geographical distribution of the plant phenophase changes and revealed their spatiotemporal dynamics in China. Based on the first leaf date （FLD） data at 12 sites derived from Chinese Phenological Observation Network （CPON） and related meteoro- logical data, we developed and validated the process-based model of FLD for Fraxinus chinensis. After reconstructing data series of FLD for Fraxinus chinensis over the study area from 1952 to 2007, we analyzed different spatiotemporal patterns of phenophase changes of this species. The results suggested that the process-based model was able to simulate the FLD accu- rately for Fraxinus chinensis on large spatial and temporal scales, because of the consideration of different budding rate re- sponded to the air temperatures during the dormancy and the quiescence in accordance with the physiological mechanism of plants. The geographical distribution of the spring phenology in temperate regions was determined by the spatial pattern of daily average air temperature. The changes of FLD for Fraxinus chinensis revealed significant phenological advances in most areas. However, it showed delayed trends in a few sites. The overall average change trend was -1 .l days/decade. This result was consistent with the advanced trend in other regions of the North Hemisphere. The changes of FLD showed a noticeable regional variation with clearer advance in the north than in the south. The FLD in northern China showed an average ad- vance as high as -2.0 days/decade （P〈0.01）. And the advance in northeastern and northwestern China was respectively -1.5 and -1.4 days/decade （P〈0.01）. Furthermore, eastern and central regions showed a minor trend, which was -1.0 days/decade （P〈0.05）. The smallest and non-significant advance appeared in southwestern and southern China.

关键词： phenophases phenological model first leaf Fraxinus chinensis

DNA barcoding of genus Toxoptera Koch （Hemiptera： Aphididae） Identification and molecular phylogeny inferred from mitochondrial COl sequences

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Insect Science 2009年第6期16卷 475-484页

作者： Jian-Feng wang ge-Xia Qiao Institute of Zoology Chinese Academy of Sciences Beijing College of Biological and Environmental Engineering Shenyang University Shenyang China

Identification of aphid species is always difficult due to the shortage of easily distinguishable morphological characters. Aphid genus Toxoptera consists of species with similar morphology and similar to Aphis in most morphological characters except the stridulatory apparatus. DNA barcodes with 1 145 bp sequences of partial mitoehondrial cytochrome-coxidase I （COI） genes were used for accurate identification of Toxoptera. Results indicated mean intraspecific sequence divergences were 1.33%, whereas mean interspecific divergences were greater at 8.29% （0.13% and 7.79% if T. aurantii 3 and T. aurantii 4 are cryptic species）. Sixteen samples were distinguished to four species correctly by COI barcodes, which implied that DNA barcoding was successful in discrimination of aphid species with similar morphology. Phylogenetic relationships among species of this genus were tested based on this portion of COI sequences. Four species of Toxoptera assembled a clade with low support in maximum-parsimony （MP） analysis, maximumlikelihood （ML） analysis and Bayesian phylogenetic trees, the genus Toxoptera was not monophyletic, and there were two sister groups, such as T. citricidus and T. victoriae, and two clades of T. aurantii which probably presented cryptic species in the genus.

关键词： Aphididae barcoding citrus aphid COI molecular phylogeny Toxoptera

Some intriguing upper bounds for separating hash families

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Science China Mathematics 2019年第2期62卷 269-282页

作者： gennian ge Chong Shangguan Xin wang School of Mathematical Sciences Capital Normal University School of Mathematical Sciences Zhejiang University Department of Mathematics Soochow University

An N ×n matrix on q symbols is called {w_1,...,w_t}-separating if for arbitrary t pairwise disjoint column sets C_1,..., C_t with |C_i|=w_i for 1 ≤i≤t, there exists a row f such that f(C_1),...,f(C_t) are also pairwise disjoint, where f(C_i) denotes the collection of componentn of C_i restricted to row f. Given integers N, q and w_1,...,w_t, denote by C(N,q,{w_1,...,w_t}) the maximal a such that a corresponding matrix does *** determination of C(N,q,{w_1,...,w_t}) has received remarkable attention during the recent years. The main purpose of this paper is to introduce two novel methodologies to attack the upper bound of C(N, q, {w_1,...,w_t}).The first one is a combination of the famous graph removal lemma in extremal graph theory and a Johnson-type recursive inequality in coding theory, and the second onc is the probabilistic method. As a consequence, we obtain several intriguing upper bounds for some parameters of C(N,q,{w_1,...,w_t}), which significantly improve the previously known results.

关键词： separating hash families Johnson-type recursive bound graph removal lemma probabilistic method

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半潜式风机变桨距控制优化研究

水力发电 2025年第1期51卷 88-92页

作者：邓森葛双义王锋国家电投集团江苏电力有限公司江苏南京210003 国家电投集团江苏海上风力发电有限公司江苏盐城224000

以半潜浮式风机为研究对象,应用控制系统仿真软件MATLAB/Simulink和基于水动力和空气动力耦合的FAST软件进行联合仿真计算。以最小化功率波动和抑制平台运动为控制目标,利用人工蚁群算法来对变桨控制的PID控制器参数进行优化,得到了风... 详细信息

以半潜浮式风机为研究对象,应用控制系统仿真软件MATLAB/Simulink和基于水动力和空气动力耦合的FAST软件进行联合仿真计算。以最小化功率波动和抑制平台运动为控制目标,利用人工蚁群算法来对变桨控制的PID控制器参数进行优化,得到了风浪联合作用下的海上浮式风机变桨距ACO-PID控制器,并将其与基线PI控制器在功率输出、转子转速、叶片桨距角和平台纵摇角参数方面进行了对比分析。结果显示,ACO-PID控制器较好的抑制了功率的波动和平台的纵摇运动,并一定程度的降低了风机主要部位的疲劳载荷,提高了风机结构的安全性,增加了风电机组的使用寿命。

关键词：半潜式风机数值仿真变桨距控制人工蚁群算法动力响应

A Bipartite Network-based Method for Prediction of Long Non-coding RNA–protein Interactions

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genomics, Proteomics & Bioinformatics 2016年第1期14卷 62-71页

作者： Mengqu ge Ao Li Minghui wang School of Information Science and Technology University of Science and Technology of China Centers for Biomedical Engineering University of Science and Technology of China

As one large class of non-coding RNAs （ncRNAs）, long ncRNAs （IneRNAs） have gained considerable attention in recent years. Mutations and dysfunction of lncRNAs have been implicated in human disorders. Many lncRNAs exert their effects through interactions with the corresponding RNA-binding proteins. Several computational approaches have been developed, but only few are able to perform the prediction of these interactions from a network-based point of view. Here, we introduce a computational method named lncRN^protein bipartite network inference （LPBNI）. LPBNI aims to identify potential lncRNA-interacting proteins, by making full use of the known IncRNA-protein interactions. Leave-one-out cross validation （LOOCV） test shows that LPBNI significantly outperforms other network-based methods, including random walk （RWR） and protein-based collaborative filtering （ProCF）. Furthermore, a case study was performed to demonstrate the performance of LPBNI using real data in predicting potential lncRNA-interacting proteins.

关键词： lncRNA Protein Interaction Bipartite network Propagation

Capacities and Failure Modes of Suction Bucket Foundation with Internal Bulkheads

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Journal of Ocean University of China 2017年第4期16卷 627-634页

作者： XIAO Zhong ge Borui wang Yan State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 P. R. China

Suction bucket foundations can be divided into four compartments by cruciform internal bulkheads,thereby yielding better capacity in certain conditions than those without internal *** yet,no systematic study has been conducted regarding the effects of cruciform internal bulkheads on the capacities of suction bucket *** this study,we established a large number of finite element models of suction bucket foundations with and without cruciform internal bulkheads and of solid embedded circular *** found the uniaxial capacities and failure modes of suction bucket foundations with various depth ratios to remain basically unaffected by internal bulkheads in uniform ***,in inhomogeneous clay with high strength heterogeneity,we observed the uniaxial moment and horizontal capacities and corresponding failure modes of suction bucket foundations with a low depth ratio to be obviously affected by internal *** this case,the uniaxial moment capacities,in particular,as well as the horizontal capacities of suction bucket foundations with cruciform internal bulkheads become obviously greater than those without internal *** combined loading,we found the failure envelopes of suction bucket foundations with and without cruciform internal bulkheads and of solid circular foundation to also be basically consistent in uniform ***,in inhomogeneous clay with high strength heterogeneity,cruciform internal bulkheads can obviously change the shapes of the failure envelopes of bucket foundations with a small depth *** conclude that when the acting vertical load or foundation depth is relatively small,suction bucket foundations with cruciform internal bulkheads can be subjected to larger moment and horizontal loads in soft clays with high strength heterogeneity.

关键词： capacity bucket foundation internal bulkheads undrained clay failure modes