检索结果-南通市图书馆

作者： GAO Si-ze NI Bang-fa ZHANG Gui-ying XIAO Cai-jin LIU Cun-xiong CHEN Zhe NIE Peng LIU Chao zhao chang-jun College of Physics Science and Engineering Technology Guangxi University

This system is designed to pick up sound signals from large volume,low-threshold energy, low-background superheated droplets bubble detectors.A sound-sensitive bubble detector is composed of a container filled with a mixture of superheated droplets and gel,a temperature and pressure control system,and an audio acquisition system attached on the outer surface of the *** superheated droplets are in a metastable and superheated state at ambient temperature and *** the outside

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企业网络地位对数据资产信息披露的影响研究

工业技术经济 2025年第1期44卷 75-84页

作者：何地赵唱庞铭辽宁大学经济学部亚澳商学院沈阳110136 大连财经学院会计学院大连116122

随着数据资产作为重要战略资源的价值日益凸显,数据资产信息披露已经成为学术界和实业界共同关注的重要议题。本文基于2009~2023年A股上市公司数据,实证检验了企业网络地位对数据资产信息披露的影响及作用机制。研究结果发现,企业网络... 详细信息

随着数据资产作为重要战略资源的价值日益凸显,数据资产信息披露已经成为学术界和实业界共同关注的重要议题。本文基于2009~2023年A股上市公司数据,实证检验了企业网络地位对数据资产信息披露的影响及作用机制。研究结果发现,企业网络地位对其数据资产信息披露水平具有正向影响。机制分析结果表明,客户集中度在企业网络地位对其数据资产信息披露水平的影响中发挥调节作用,即客户集中度越低,企业网络地位对其数据资产信息披露水平的影响越强。异质性分析结果发现,对于非国有企业、多阶(长链)结构和小规模企业而言,企业网络地位对数据资产信息披露的影响效果尤为明显。本文揭示了企业网络地位影响数据资产信息披露的微观机制,为我国完善数据要素市场制度以及促进数字经济高质量发展提供了政策启示。

关键词：企业网络地位数字资产信息披露客户集中度文本分析法信号传递理论数字经济数字化转型企业竞争力

Sensitive study of the long and short surface wave-induced vertical mixing in a wave-circulation coupled model

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Acta Oceanologica Sinica 2012年第4期31卷 1-10页

作者： zhao chang College of Physical and Environmental Oceanography Ocean University of China Qingdao 266100 China Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao 266061 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

The previous studies by the MASNUM research team have shown the effectiveness of the wave- induced mixing （By） in improving the simulation of upper-ocean thermal structure. The mech- anisms of Bv are further investigated by incorporating different Bv products into the MASNUM wave-circulation coupled model. First, experiments were designed to explore the effects of By, which contain the contributions at different wave lengths （l）. The results of three experiments, the non-By case, the short-wave case （l 〈300 m）, and the long-wave case （l 〉300 m） are compared, and it is found that the long waves are the most important component for By to generate mixing in the upper ocean. As the swell plays dominant role in mixing, the parameterization of Bv into wind may be not a proper way. Second, Bv effects at different time-scales, including daily and monthly, were examined. The results show that the monthly averaged By has larger impact than the daily averaged Bv, especially in summer.

关键词： wave-induced mixing wave-circulation coupled model long surface wave-inducedmixing daily mean wave-induced mixing monthly mean wave-induced mixing

基于随机森林模型的呼中冻土区土壤碳空间分布特征

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森林工程 2025年第1期41卷 100-107页

作者：杜倩王岩万祖梁赵昶刘学梁素钰黑龙江省生态研究所哈尔滨150081 黑龙江省生态研究所森林生态与林业生态工程重点实验室哈尔滨150081

以大兴安岭呼中典型冻土区为研究对象,研究表层(0~15、15~30 cm)土壤碳储量空间分布规律。通过野外调查、采样和室内分析,基于Landsat 8 OLI影像,利用随机森林(RF)算法建模,分析大兴安岭冻土区表层土壤有机碳空间分布状况。在13个遥感... 详细信息

以大兴安岭呼中典型冻土区为研究对象,研究表层(0~15、15~30 cm)土壤碳储量空间分布规律。通过野外调查、采样和室内分析,基于Landsat 8 OLI影像,利用随机森林(RF)算法建模,分析大兴安岭冻土区表层土壤有机碳空间分布状况。在13个遥感变量因子中筛选相关性最高变量,确定海拔、ARVI、VIGreen、EVI、OSAVI、NDVI,6个环境变量相关性最高,可作为自变量。结果表明,当节点分裂次数(leaf)值为5,决策树数量(trees)值为900时,预测模型的训练集和测试集最为接近,表明此时的模型稳定性最好,0~15、15~30 cm土层训练集R^(2)的拟合精度分别为0.23、0.43,测试集R^(2)的拟合精度分别为0.35、0.24。以此参数预测表层(0~15、15~30 cm)土壤碳储量空间土壤碳空间分布状况分布特征,0~15和15~30 cm土壤碳密度平均值为7.40 kg/m^(2)和14.80 kg/m^(2),0~15 cm土层土壤碳储量分布大致为由南向北逐渐增加,15~30 cm土层土壤碳储量分布差异不明显,但南向略高于北向。

关键词： GIS 土壤碳储量冻土 RF模型大兴安岭

On the Linear Complexity of a Class of Periodic Sequences Derived from Euler Quotients

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Chinese Journal of Electronics 2023年第2期32卷 262-272页

作者： LUO Bingyu ZHANG Jingwei zhao chang'an School of Mathematics Sun Yat-sen University School of Information Science Guangdong University of Finance and Economics Guangdong Key Laboratory of Information Security State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences

In this paper, a family of binary sequences derived from Euler quotients with RSA modulus pq is introduced. Here two primes p and q are distinct and satisfy gcd(pq,(p-1)(q-1))=1. The linear complexities and minimal polynomials of the proposed sequences are determined. Besides, this kind of sequences is shown not to have correlation of order four although there exist some special relations by the properties of Euler quotients.

关键词： Correlation Complexity theory Cryptography Random sequences

Molecular Understanding of Charge Storage in MoS_(2)Supercapacitors with Ionic Liquids

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Energy & Environmental Materials 2021年第4期4卷 631-637页

作者： Zhun Liang chang zhao Wei zhao Yuan Zhang Pattarachai Srimuk Volker Presser Guang Feng State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan Hubei 430074China Nano Interface Center for Energy School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan Hubei 430074China Department of Chemical and Biomolecular Engineering Vanderbilt University2201 West End AvenueNashville TN 37235USA INM-Leibniz Institute for New Materials Campus D22Saarbrucken 66123Germany Saarland University Campus D22Saarbrucken 66123Germany

Owing to high electrical conductivity and ability to reversibly host a variety of inserted ions,2D metallic molybdenum disulfide(1 T-MoS_(2))has demonstrated promising energy storage performance when used as a supercapacitor ***,its charge storage mechanism is still not fully understood,in particular,how the interlayer spacing of 1 T-MoS_(2)would affect its capacitive *** this work,molecular dynamics simulations of 1 T-MoS_(2)with interlayer spacing ranging from 0.615 to 1.615 nm have been performed to investigate the resulting charge storage capacity in ionic *** reveal a camel-like capacitance-potential relation,and MoS_(2)with an interlayer spacing of 1.115 nm has the highest volumetric and gravimetric capacitance of118 F cm^(-3)and 42 F g^(-1),*** ions in MoS_(2)with an interlayer spacing of 1.115 nm diffuse much faster than with interlayer spacings of 1.365 and 1.615 nm,the MoS_(2)with larger interlayer spacing has a much faster-charging *** analyses reveal that the ion number density and its charging speed,as well as ion motion paths,have significant impacts on the charging *** work helps to understand how the interlayer spacing affects the interlayer ion structures and the capacitive performance of MoS_(2),which is important for revealing the charge storage mechanism and designing MoS_(2)supercapacitor.

关键词： charge storage mechanism ionic liquids molecular dynamics simulation molybdenum disulfide supercapacitors

Phylogenetic Analysis and Expression Patterns of the MAPK Gene Family in Wheat (Triticum aestivum L.)

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Journal of Integrative Agriculture 2012年第8期11卷 1227-1235页

作者： LIAN Wei-wei TANG Yi-miao GAO Shi-qing ZHANG zhao zhao Xin zhao chang-ping Beijing Engineering and Technique Research Center of Hybrid Wheat Beijing Academy of Agricultural and Forestry Sciences Beijing 100097 P.R.China College of Life Science Capital Normal University Beijing 100048 P.R. China

Mitogen activated protein kinases （MAPK） cascades based on protein phosphorylation play an important role in plant growth and development. In this study, we have identified 15 putative members of the wheat MAPK gene （TaMPK） family through an in silico search of wheat expressed sequence tags （EST） databases based on the presence of amino acid sequence of Arabidopsis and rice MAPKs. Phylogenetic analyses of MAPKs from wheat, rice and Arabidopsis genomes have classified them into seven subgroups （A, B, C, D, E, F, and G）. Using the available EST information as a source of expression data, the MAPK family genes from Triticum aestivum were detected in diverse tissues. Further expression analysis of the MAPKs in NCBI EST database revealed that their transcripts were most abundant in callus （20%）, followed by leaf （12%） and inflorescence （12%）. Most MAPK family genes showed some tissue specificity.

关键词： wheat MAPK EST phylogenetic analysis profile

Automatic Diabetic Retinopathy Screening via Cascaded Framework Based on Image- and Lesion-Level Features Fusion

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Journal of Computer Science & Technology 2019年第6期34卷 1307-1318页

作者： Cheng-Zhang Zhu Rong Hu Bei-Ji Zou Rong-chang zhao chang-Long Chen Ya-Long Xiao College of Literature and Journalism Central South UniversityChangsha 410083China Hunan Province Engineering Technology Research Center of Computer Vision and Intelligent Medical Treatment changsha 410083 China School of Computer Science and Engineering Central South UniversityChangsha 410083China

The early detection of diabetic retinopathy is crucial for preventing ***,it is time-consuming to analyze fundus images manually,especially considering the increasing amount of medical *** this paper,we propose an automatic diabetic retinopathy screening method using color fundus *** approach consists of three main components:edge-guided candidate microaneurysms detection,candidates classification using mixed features,and diabetic retinopathy prediction using fused features of image level and lesion *** divide a screening task into two sub-classification tasks:(1)verifying candidate microaneurysms by a naive Bayes classifier;(2)predicting diabetic retinopathy using a support vector machine *** approach can effectively alleviate the imbalanced class distribution *** evaluate our method on two public databases:Lariboisière and Messidor,resulting in an area under the curve of 0.908 on Lariboisière and 0.832 on *** scores demonstrate the advantages of our approach over the existing methods.

关键词： diabetic retinopathy feature fusion microaneurysm naive Bayes support vector machine

FeatureMatching Combining Variable Velocity Model with Reverse Optical Flow

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Computer Systems Science & Engineering 2023年第5期45卷 1083-1094页

作者： chang zhao Wei Sun Xiaorui Zhang Xiaozheng He Jun Zuo Wei zhao College of Automation Nanjing University of Information Science&TechnologyNanjing210044China Wuxi Research Institute Nanjing University of Information Science&TechnologyWuxi214100China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing210044China Department of Civil and Environmental Engineering Rensselaer Polytechnic InstituteTroy12180NYUSA

The ORB-SLAM2 based on the constant velocity model is difficult to determine the search window of the reprojection of map points when the objects are in variable velocity motion,which leads to a false matching,with an inaccurate pose estimation or failed *** address the challenge above,a new method of feature point matching is proposed in this paper,which combines the variable velocity model with the reverse optical flow ***,the constant velocity model is extended to a new variable velocity model,and the expanded variable velocity model is used to provide the initial pixel shifting for the reverse optical flow *** the search range of feature points is accurately determined according to the results of the reverse optical flow method,thereby improving the accuracy and reliability of feature matching,with strengthened interframe tracking ***,we tested on TUM data set based on the RGB-D *** results show that this method can reduce the probability of tracking failure and improve localization accuracy on SLAM(Simultaneous Localization and Mapping)*** with the traditional ORB-SLAM2,the test error of this method on each sequence in the TUM data set is significantly reduced,and the root mean square error is only 63.8%of the original system under the optimal condition.

关键词： Visual SLAM feature point matching variable velocity model reverse optical flow

Mechanical Analysis of Dead Load Crown and Structure Parameter of Hydraulic Elastic Bulging Roll

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Journal of Iron and Steel Research International 2003年第3期10卷 28-31页

作者： zhao chang-cai LI Wei-min LIU Zhu-bai Yanshan University

The dead load crown of hydraulic elastic bulging roll was discussed using the theory of elastically supported beam,and the dead load experiment was carried out. The theoretical calculation is consistent with the experimental result. The structure parameters for the thickness of roll sleeve,the length of the oil groove and the crown of roll were discussed. The fundamental principle of determining the parameters was put forward. The theoretical basis of the application of the hydraulic elastic bulging roll was established.

关键词： hydraulic elastic bulging roll bulging crown dead load