检索结果-南通市图书馆

Study on Capturing PM2.5 Capability of Tree Species in Different Functional Areas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Study on Capturing PM2.5 Capability of Tree Species in Diffe...

International Conference on Industrial Technology and Management Science(ITMS 2015)

作者： J.Yang B.Z.Xie h.shi h.X.Wang Y.h.Wang School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry

Trees can capture PM on account of their foliage’s structure, thus, improving air quality. We determined leaf PM-retaining capability(PM, PM, PM) of evergreen shrub(Euonymus japonicas) and decicuous trees(Sophora japonica, Fraxinus chinensis, Ginkgo biloba, Populus tomentosa) in different functional areas. The leaf micromorphological structure was observed using a field emission environmental scanning electron microscopy. We found that E. japonicas should be planted in traffic and industrial areas, while S. japonica, G. biloba, F. chinensis should be chosen as complementary in clean areas. S. japonica, G. biloba were adapted well to polluted environment, but, F. chinensis was not.

关键词： CAPTURING PM2.5 DIFFERENT FUNCTIONAL AREAS structural feature

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

烟草调制过程中相关物质的测定

中国烟草科学 2002年第4期23卷 32-34页

作者：雷丽萍 L.Luo h.shi F.F.Fannin h.R.Burton L.P.Bush 云南烟草科学研究院农业研究所生物重点实验室昆明65023 美国肯塔基大学农学系

为提高烟叶有益成分,降低烟叶有害成分提供依据,采用相同的栽培调制技术,对不同的烟草品种进行了系统的对比研究,分别测定了7个烟草品种的鲜、干叶片厚度,重量和表面蜡质含量,并测定了这些样品在调制后的烟碱、次生物碱、硝态氮含量,烟... 详细信息

为提高烟叶有益成分,降低烟叶有害成分提供依据,采用相同的栽培调制技术,对不同的烟草品种进行了系统的对比研究,分别测定了7个烟草品种的鲜、干叶片厚度,重量和表面蜡质含量,并测定了这些样品在调制后的烟碱、次生物碱、硝态氮含量,烟草特有亚硝胺(TSNA)总量及NNN、NAT、NAB、NNK含量。

关键词：烟草调制测定成分

Enhancing Log Anomaly Detection with Semantic Embedding and Integrated Neural Network Innovations

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials and Continua 2024年第3期80卷 3991-4015页

作者： Xu Z. Wang Z. Xu J. shi h. Zhao h. School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 China

System logs, serving as a pivotal data source for performance monitoring and anomaly detection, play an indispensable role in assuring service stability and reliability. Despite this, the majority of existing log-based anomaly detection methodologies predominantly depend on the sequence or quantity attributes of logs, utilizing solely a single Recurrent Neural Network (RNN) and its variant sequence models for detection. These approaches have not thoroughly exploited the semantic information embedded in logs, exhibit limited adaptability to novel logs, and a single model struggles to fully unearth the potential features within the log sequence. Addressing these challenges, this article proposes a hybrid architecture based on a multiscale convolutional neural network, efficient channel attention and mogrifier gated recurrent unit networks (LogCEM), which amalgamates multiple neural network technologies. Capitalizing on the superior performance of robustly optimized BERT approach (RoBERTa) in the realm of natural language processing, we employ RoBERTa to extract the original word vectors from each word in the log template. In conjunction with the enhanced Smooth Inverse Frequency (SIF) algorithm, we generate more precise log sentence vectors, thereby achieving an in-depth representation of log semantics. Subsequently, these log vector sequences are fed into a hybrid neural network, which fuses 1D Multi-Scale Convolutional Neural Network (MSCNN), Efficient Channel Attention Mechanism (ECA), and Mogrifier Gated Recurrent Unit (GRU). This amalgamation enables the model to concurrently capture the local and global dependencies of the log sequence and autonomously learn the significance of different log sequences, thereby markedly enhancing the efficacy of log anomaly detection. To validate the effectiveness of the LogCEM model, we conducted evaluations on two authoritative open-source datasets. The experimental results demonstrate that LogCEM not only exhibits excellent ac

关键词： anomaly detection Deep learning log analysis natural language processing

CONVERGENCE ANALYSIS OF NONCONFORMING QUADRILATERAL FINITE ELEMENT METhODS FOR NONLINEAR COUPLED SChRODINGER-hELMhOLTZ EQUATIONS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2024年第4期42卷 979-998页

作者： Dongyang shi houchao Zhang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

The focus of this paper is on two novel linearized Crank-Nicolson schemes with nonconforming quadrilateral finite element methods(FEMs)for the nonlinear coupled Schrodinger-helmholtz *** L^(2) and h^(1) estimates of orders O(h^(2)+τ^(2))and O(h^(2)+τ^(2))are derived respectively without any grid-ratio condition through the following two *** is that a time-discrete system is introduced to split the error into the temporal error and the spatial error,which leads to optimal temporal error estimates of order O(τ^(2))in L^(2) and the broken h^(1)-norms,as well as the uniform boundness of numerical solutions in L^(∞) *** other is that a novel projection is utilized,which can iron out the difficulty of the existence of the consistency *** leads to derive optimal spatial error estimates of orders O(h^(2))in L^(2)-norm and O(h)in the broken h^(1)-norm under the h^(2) regularity of the solutions for the time-discrete *** last,two numerical examples are provided to confirm the theoretical ***,h is the subdivision parameter,and τ is the time step.

关键词： Schrodinger-helmholtz equations Nonconforming FEMs Linearized Crank-Nicolson scheme Optimal error estimates

UNIFORM SUPERCONVERGENCE ANALYSIS OF A TWO-GRID MIXED FINITE ELEMENT METhOD FOR ThE TIME-DEPENDENT BI-WAVE PROBLEM MODELING D-WAVE SUPERCONDUCTORS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2024年第2期42卷 415-431页

作者： Yanmi Wu Dongyang shi PLA Information Engineering University Zhengzhou 450001China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

In this paper,a two-grid mixed finite element method(MFEM)of implicit Backward Euler(BE)formula is presented for the fourth order time-dependent singularly perturbed Bi-wave problem for d-wave superconductors by the nonconforming EQ_(1)^(rot) *** this approach,the original nonlinear system is solved on the coarse mesh through the Newton iteration method,and then the linear system is computed on the fine mesh with Taylor’s *** on the high accuracy results of the chosen element,the uniform superclose and superconvergent estimates in the broken h^(1)-norm are derived,which are independent of the negative powers of the perturbation parameter appeared in the considered *** results illustrate that the computing cost of the proposed two-grid method is much less than that of the conventional Galerkin MFEM without loss of accuracy.

关键词： Time-dependent Bi-wave problem Two-grid mixed finite element method Uniform superclose and superconvergent estimates

急性髌骨横向脱位后内侧髌股韧带撕裂的评估:高频超声与MR对比研究

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

国际医学放射学杂志 2015年第2期 194-195页

作者： G.Y.Zhang L.Zheng h.Y.Ding E.M.Li B.S.Sun h.shi 郭凌飞 Department of Ultrasonography Qianfoshan HospitalShandong University

摘要目的本研究摘要目的是比较高频超声与MRI对急性髌骨横向脱位后(LPD)内侧髌股韧带撕裂(MPFL)的诊断价值。方法对97例急性LPD病人进行高频超声和MRI检查

关键词：高频超声 MRI LPD MPFL MR 髌股韧带髌骨下肢骨

Rhodium-catalyzed addition reactions of benzylic C–h bonds to cyclic N-sulfonyl ketimines viaπ-coordination

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong Li hang shi Department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and ***,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic *** this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–h bonds to cyclic N-sulfonyl ketamines throughπ-*** strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzylic deprotonation Cyclic N–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

Effect of Bogie Cavity End Wall Inclination on Flow Field and Aerodynamic Noise in the Bogie Region of high-Speed Trains

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第5期139卷 2175-2195页

作者： Jiawei shi Jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China

Combining the detached eddy simulation(DES)method and Ffowcs Williams-hawkings(FW-h)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically ***,the simulation is conducted based on a simplified cavity-bogie model,including five cases with different inclination angles of the front and rear walls of the *** comparing and analyzing the flow field and acoustic results of the five cases,the influence of the regularity and mechanism of the bogie cavity end wall inclination on the flow field and the aerodynamic noise of the bogie region are ***,the noise reduction strategy determined by the results of the simplified cavity-bogie model is applied to a three-car marshaling train model to verify its effectiveness when applied to the real *** results reveal that the forward inclination of the cavity front wall enlarges the influence area of shear vortex structures formed at the leading edge of the cavity and intensifies the interaction between the vortex structures and the front wheelset,frontmotor,and front gearbox,resulting in the increase of the aerodynamic noise generated by the bogie *** backward inclination of the cavity rear wall is conducive to guiding the vortex structures flow out of the cavity and weakening the interaction between the shear vortex structures and the cavity rear wall,leading to the reduction of the aerodynamic noise generated by the bogie *** the rear end wall of the foremost bogie cavity of the head car is a feasible aerodynamic noise reduction measure for high-speed trains.

关键词： Bogie cavity flow aerodynamic noise end wall inclination

Infrared Fault Detection Method for Dense Electrolytic Bath Polar Plate Based on YOLOv5s

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials and Continua 2024年第3期80卷 4859-4874页

作者： Yu h. hang Y. shi S. Wu K. Zhang Y. Software Engineering Department of Computer Science Changzhou University Changzhou 213146 China Electrical Engineering Department of Computer Science Changzhou University Changzhou 213146 China

Electrolysis tanks are used to smelt metals based on electrochemical principles, and the short-circuiting of the pole plates in the tanks in the production process will lead to high temperatures, thus affecting normal production. Aiming at the problems of time-consuming and poor accuracy of existing infrared methods for high-temperature detection of dense pole plates in electrolysis tanks, an infrared dense pole plate anomalous target detection network YOLOv5-RMF based on You Only Look Once version 5 (YOLOv5) is proposed. Firstly, we modified the Real-Time Enhanced Super-Resolution Generative Adversarial Network (Real-ESRGAN) by changing the U-shaped network (U-Net) to Attention U-Net, to preprocess the images; secondly, we propose a new Focus module that introduces the Marr operator, which can provide more boundary information for the network; again, because Complete Intersection over Union (CIOU) cannot accommodate target borders that are increasing and decreasing, replace CIOU with Extended Intersection over Union (EIOU), while the loss function is changed to Focal and Efficient IOU (Focal-EIOU) due to the different difficulty of sample detection. On the homemade dataset, the precision of our method is 94%, the recall is 70.8%, and the map@.5 is 83.6%, which is an improvement of 1.3% in precision, 9.7% in recall, and 7% in map@.5 over the original network. The algorithm can meet the needs of electrolysis tank pole plate abnormal temperature detection, which can lay a technical foundation for improving production efficiency and reducing production waste. Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： Focal-EIoU loss Infrared polar plate fault detection Marr boundary detection operator Real-ESRGAN YOLOv5