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Spatial heterogeneity and population risk analysis of cotton bollworm, Helicoverpa armigera, in ChinaKey words spatial characteristics, spatial pattern, semivariance, population management, geostatistics, Helicoverpa armigera, population regulation

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Insect Science 2005年第4期12卷 255-262页

作者： SHAO-KUI GE RAYmoND I. CARRUTHERS ZU-FEI MA GUANG XUEZHANG dian-mo li State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of SciencesBeijing China USDA-ARS Exotic & Invasive Weeds Research Unit Albany California US

In this study, semivariance was used to quantitatively measure the spatial heterogeneity for the egg population of cotton bollworm during a growing season. The typical characteristic parameters of theoretical semivariance models against lag distances were applied to measure components of spatial heterogeneity： trend, range, spatial dependence, and the strength of spatial dependence. Then, kriging interpolation was used to evaluate the population risk of cotton bollworm exceeding economic thresholds. From early June through early September, the population densities were sampled 10 times in the study field. Results showed that the spatial patterns were related to population density. For its low-density population, the spatially heterogeneous trends were usually of spherical shapes; but for highdensity ones, the trends shifted to Gaussian shapes. The spatial dependence appeared at varied distances ranging from 52 meters to 936 meters, and the spatial dependence was in the range of 0.39-288.60, which changed with population densities. While having high heterogeneity, the strength of spatial dependence became much stronger. Results of population risk analysis showed that there was a high risk during its early stages, especially in mid-June. In August, population risk was so low that it did not need to be controlled.

关键词： spatial characteristics spatial pattern semivariance population management geostausucs Helicoverpa armigera population regulation

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基于多分支增强和融合注意力机制的水下图像增强算法

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陕西科技大学学报 2025年第1期43卷 193-202页

作者：姚斌韩典芝徐轩李婉陕西科技大学电子信息与人工智能学院陕西西安710021

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计... 详细信息

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计了青品色温修复模块和模糊恢复模块对水下图像进行色彩矫正和模糊恢复.然后,基于对多个分支特征的互补性考虑,采用循环合并策略将多个分支增强的特征利用自适应融合模块进行融合,逐步增强图像细节.最后,设计了融合注意力模块,用于深度挖掘图像在通道维度和像素维度的相关性矩阵,以提高增强图像的真实性.实验结果表明,与现有算法相比,提出的水下图像增强算法去模糊效果较好且颜色更真实,可以有效改善水下图像色偏和模糊的问题.

关键词：水下图像增强多分支增强融合注意力生成对抗网络

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Mechanism of aluminum complexation in oxidative activity of leaching bacteria in a fluoride-containing bioleaching system

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Rare Metals 2019年第1期38卷 87-94页

作者： Xiang li Jian-Kang Wen Xiao-Lan mo Wu Biao dian-Zuo Wang Hong-Ying Yang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals School of Metallurgy Northeastern University

Accumulation of toxic ions in leachate is one factor limiting bioleaching applications. The effect of fluoride ions on the growth of bioleaching microorganisms has been extensively emphasized. In this study, HF is found to be the toxic form of fluoride that affects the bacterial activity under acidic conditions. The added aluminum could compete with H^+ to complex with F-, thus significantly decrease the concentration of HF and finally reduce the toxicity of fluoride to bacteria. When F^-/Al^(3+)concentration ratio is 0.5:1.0, Fe^(2+) oxidation rate could reach 0.167 g·L^(-1)·h^(-1), close to that of the biotic control group(0.195 g·L^(-1)·h^(-1)). The competitive complexation mechanism of fluoride by AlF_n^(3-n) results in stability constants of AlF_n^(3-n) complex(7.00) that are larger than those of HF(3.18). The F^-/Al^(3+) concentration ratio in the medium could affect the speciation of AlF_n^(3-n) *** the decrease in F^-/Al^(3+) concentration ratio, the coordination numbers of AlF_n^(3-n) decrease. Finally, the feasibility of fluoride detoxification by aluminum ion is verified. This work has meaningful implications for fluoride-containing bacterial bioleaching systems.

关键词： Competitive complexation Detoxification Fluoride Aluminum Bioleaching

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A Human Active Lower limb model for Chinese Pedestrian Safety Evaluation

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Journal of Bionic Engineering 2021年第4期18卷 872-886页

作者： Fuhao mo dian Luo Zheng Tan Bo Shang Xiaojiang Lv Donghua Zhou State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan UniversityHunan 410082China School of Mechanical Engineerings Hunan University of Science and Technology Xiangtan 411201China Pan Asia Technical Automotive Center Co. LtdShanghai 201201China Zhejiang Key Laboratory of Automobile Safety Technology Geely Automobile Research InstituteNingbo 315336China Shanghai Key Laboratory of Forensic Medicine Shanghai Forensic Service PlatformAcademy of Forensic ScienceMinistry of JusticeShanghai 200063China

A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the present study aims to establish and validate a finite element lower limb model representing 50th Chinese male size for pedestrian safety research,then compare its biomechanical responses with the general models currently in wide use in the world for pedestrian safety *** the vehicle-pedestrian impact loading environment,the previously developed lower limb model with three-dimensional muscles was adjusted and validated through the related ***,the biomechanical responses of the validated model were compared with the Total Human model for Safety(THUMS)and Advanced Pedestrian Legform Impactor(aPli)models by combing with four typical *** results showed that both consistency and significant differences of biomechanical responses existed between the present model and the other two *** injury measurements of the thigh region of the present model showed extremely large differences with the other two models,while the tibia and Medial Collateral ligament(MCL)injury measurements show similar ***,it can be concluded that directly using the aPli or THUMS models for Chinese pedestrian safety evaluation is not robust concerning both kinematic responses and injury measurements.

关键词： lower limb injury biomechanics human body modeling pedestrian safety finite element analysis

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Coalescence-dominated microstructure evolution during solidification of 20SiMn steel

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Journal of Iron and Steel Research International 2020年第5期27卷 506-516页

作者： Xiao-ping Ma dian-zhong li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina

The evolution of microstructures during the solidification of 20SiMn steel was *** dominant role of coalescence was revealed by analyzing the quenched microstructures and the solute *** the parameter range investigated,including the slow solidification,the fast solidification and the directional solidification,the coalescence can happen at multiple solidification stages and on *** the directional solidification,the ternary and fourth dendritic arms coalesce into the secondary dendritic arms,and the secondary dendritic arms further coalesce to produce the cellular *** cellular crystals become coarse through further *** the non-directional solidification,the initial microstructures are discrete crystals without the dendritic *** the dendritic arms and dendritic stems appearing in the later solidification stage are produced by the coalescence on *** coalescence is more significant in the later solidification *** mechanism of coalescence is attributed to different melt compositions in different local domains and the reduction of the interface energy.

关键词： Solidification Microstructure Coalescence Steel Microsegregation

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Indexing Techniques of Distributed Ordered Tables： A Survey and Analysis

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Journal of Computer Science & Technology 2018年第1期33卷 169-189页

作者： Chen Feng Chun-dian li Rui li State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China~TT ' University of Chinese Academy of Sciences Beijing 100049 China Tencent Inc. Beijing 100080 China

Many NoSQL （Not Only SQL） databases were proposed to store and query on a huge amount of data. Some of them like BigTable, PNUTS, and HBase, can be modeled as distributed ordered tables （DOTs）. Many additional indexing techniques have been presented to support queries on non-key columns for DOTs. However, there was no comprehensive analysis or comparison of these techniques, which brings troubles to users in selecting or proposing a proper indexing technique for a certain workload. This paper proposes a taxonomy based on six indexing issues to classify indexing techniques on DOTs and provides a comprehensive review of the state-of-the-art techniques. Based on the taxonomy, we propose a performance model named QSmodel to estimate the query time and storage cost of these techniques and run experiments on a practical workload from Tencent to evaluate this model. The results show that the maximum error rates of the query time and storage cost are 24.2% and 9.8% respectively. Furthermore, we propose IndexComparator, an open source project that implements representative indexing techniques. Therefore, users can select the best-fit indexing technique based on both theoretical analysis and practical experiments.

关键词： database Not Only SQL (NoSQL) range query indexing

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定窑遗址出土制瓷原料的科学分析

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光谱学与光谱分析 2025年第1期45卷 72-81页

作者：陈殿崔剑锋秦大树黄信李鑫北京师范大学历史学院陶瓷考古与艺术研究中心北京100875 考古科学教育部重点实验室(北京大学) 北京100871 浙大城市学院考古学系浙江杭州310015 河北省文物考古研究院河北石家庄050031 中国社会科学院考古研究所北京100101

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了ED-XRF成分分析和XRD结构分析等光谱学分析。ED-XRF成分分析显示,这些原料可能包括单一原料和... 详细信息

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了ED-XRF成分分析和XRD结构分析等光谱学分析。ED-XRF成分分析显示,这些原料可能包括单一原料和混合原料两种。其中单一原料包括岩石、粘土以及草木灰。混合原料则包括胎料和釉料两种。XRD结构分析表明用于定窑白瓷生产高岭土类原料是含有蒙脱石和方解石的伴生石英的长石类矿物原料。高铁粘土类原料由于铁含量特别高,应当是用于配黑釉的粘土。钙质原料的分析与康葆强等学者对定窑配釉用的灰料可能使用了40%的白灰和60%的松木灰配制的结论相同。同时,还发现了釉灰,即草木煅烧石灰石后形成的混合灰料。在分析定窑白瓷釉时,认为五代的白瓷釉可能使用了釉灰配制,因此定窑釉灰的使用可能推早到五代,这是目前发现使用釉灰配釉最早的实例。对制胎原料XRD晶相分析的结果表明,除了石英和高岭石占主要比重外,还含有长石、蒙脱石、方解石等岩石类矿物。从对单一原料的X射线衍射的分析结果看,石英是粘土以及岩石这类单一原料中都含有的一类矿物,因此可能石英并非必须要添加的胎体原料。石英和高岭石是粘土原料中的主要成分,因此制胎原料应该主要以岩石类原料和粘土作为主要配料。定窑细白瓷胎料可能使用了粘土类原料配合第一类岩石类原料的配方,其配比在金代时大约为1∶1左右,北宋时期可能约为7∶3(粘土∶岩石),五代时大概为6∶4左右。对制釉原料分析结果表明,定窑配釉原料是岩石类原料与釉灰配合形成的,五代、北宋时岩石和灰的比例约为9∶1,金代时石:灰达到了9.5∶0.5。这使得我们对定窑鼎盛时期的白瓷胎釉配方有了更加清晰的了解,从而为开展定窑的复烧提供了确凿的依据。

关键词：定窑制瓷原料光谱学分析

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Learning the external and internal priors for multispectral and hyperspectral image fusion

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Science China(Information Sciences) 2023年第4期66卷 64-78页

作者： Shutao li Renwei dian Haibo liU College of Electrical and Information Engineering Hunan University School of Robotics Hunan University

Recently, multispectral image(MSI) and hyperspectral image(HSI) fusion has been a popular topic in high-resolution HSI acquisition. This fusion leads to a challenging underdetermined problem, which image priors are used to regularize, aiming at improving fusion accuracy. To fully exploit HSI priors, this paper proposes two kinds of priors, i.e., external priors and internal priors, to regularize the fusion *** external prior represents the general image characteristics and is learned from abundant training data by using a Gaussian denoising convolutional neural network(CNN) trained in the additional gray images. An internal prior represents the unique characteristics of the HSI and MSI to be fused. To learn the external prior, we first segment the MSI into several superpixels and then enforce a low-rank constraint for each superpixel, which can well model local similarities in the HSI. In addition, to model a low-rank property in the spectral mode, the high-resolution HSI is decomposed into a low-rank spectral basis and ***, we formulate the fusion as an external and internal prior-regularized optimization problem, which is efficiently tackled through the alternating direction method of multipliers. Experiments on simulated and real datasets demonstrate the superiority of the proposed method.

关键词： multispectral and hyperspectral image fusion external and internal prior learning high-resolution hyperspectral imaging

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Vinylogous Fluorine Stabilizing Effect Enables Rational Design of a Novel Donor-Acceptor Cyclopropane and Its Applications in[3+2]Cycloaddition Reaction and Ring-Opening Polymerization

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Chinese Journal of Chemistry 2024年第22期42卷 2723-2727页

作者： Yue li dian-Feng Chen Hefei National Research Centerfor Physical Sciences at the Microscale and Department of Polymer Science and Engineering University of ScienceandTechnologyof ChinaHefeiAnhui 230026China

Comprehensive Summary Discovery of unprecedented donor-acceptor patterns can essentially enrich the chemistry of donor-acceptor *** herein introduce a concept of vinylogous fluorine stabilizing effect,which guides rational design of a novel donor-acceptor cyclopropane employing gem-difluorovinyl group as the electron donor,namely *** of such dFVCPs in a[3+2]cycloaddition with aldehydes and a controlled ring-opening polymerization by a Mg(OTf)2/DIPEA/C(sp3)-H initiator system have been demonstrated,providing direct access to fluorine-containing tetrahydrofurans and all-carbon main-chain polymers.

关键词： Donor-acceptor cyclopropane gem-Difluorovinyl group Vinylogous fluorine stabilizing effect [3+2]cycloaddition Ring-opening polymerization Strainedmolecules monomers lonic polymerization

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model parameters estimation of aero-engine based on hybrid optimization algorithm

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航空动力学报 2011年第7期26卷 1665-1671页

作者： li Qiu-hong li Ye-bo JIANG dian-wen (College of Energy and Power EngineeringNanjing University of Aeronautics and Astronautics Nanjing 210016 China

A hybrid optimization algorithm for the time-domain identification of multivariable,state space model for aero-engine was presented in this *** optimization procedure runs particle swarm optimization(PSO) and least squares optimization(LSO) "in series".PSO starts from an initial population and searches for the optimum solution by updating ***,it can sometimes run into a suboptimal *** LSO can start from the suboptimal solution of PSO,and get an optimum solution by conjugate gradient *** algorithm is suitable for the high-order multivariable system which has many parameters to be estimated in wide *** optimization algorithm is applied to estimate the parameters of a 4-input 4-output state variable model(SVM) for *** simulation results demonstrate the effectiveness of the proposed algorithm.

关键词： aero-engine state variable model(SVM) particle swarm optimization(PSO) least squares optimization(LSO) hybrid optimization algorithm

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