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Scheme Based on Multi-Level Patch Attention and Lesion Localization for Diabetic Retinopathy Grading 被引量:1
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作者 Zhuoqun Xia Hangyu Hu +4 位作者 Wenjing Li Qisheng Jiang Lan Pu Yicong Shu Arun Kumar Sangaiah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期409-430,共22页
Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional ... Early screening of diabetes retinopathy(DR)plays an important role in preventing irreversible blindness.Existing research has failed to fully explore effective DR lesion information in fundus maps.Besides,traditional attention schemes have not considered the impact of lesion type differences on grading,resulting in unreasonable extraction of important lesion features.Therefore,this paper proposes a DR diagnosis scheme that integrates a multi-level patch attention generator(MPAG)and a lesion localization module(LLM).Firstly,MPAGis used to predict patches of different sizes and generate a weighted attention map based on the prediction score and the types of lesions contained in the patches,fully considering the impact of lesion type differences on grading,solving the problem that the attention maps of lesions cannot be further refined and then adapted to the final DR diagnosis task.Secondly,the LLM generates a global attention map based on localization.Finally,the weighted attention map and global attention map are weighted with the fundus map to fully explore effective DR lesion information and increase the attention of the classification network to lesion details.This paper demonstrates the effectiveness of the proposed method through extensive experiments on the public DDR dataset,obtaining an accuracy of 0.8064. 展开更多
关键词 DDR dataset diabetic retinopathy lesion localization multi-level patch attention mechanism
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Deep neural network based on multi-level wavelet and attention for structured illumination microscopy
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作者 Yanwei Zhang Song Lang +2 位作者 Xuan Cao Hanqing Zheng Yan Gong 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期12-23,共12页
Structured illumination microscopy(SIM)is a popular and powerful super-resolution(SR)technique in biomedical research.However,the conventional reconstruction algorithm for SIM heavily relies on the accurate prior know... Structured illumination microscopy(SIM)is a popular and powerful super-resolution(SR)technique in biomedical research.However,the conventional reconstruction algorithm for SIM heavily relies on the accurate prior knowledge of illumination patterns and signal-to-noise ratio(SNR)of raw images.To obtain high-quality SR images,several raw images need to be captured under high fluorescence level,which further restricts SIM’s temporal resolution and its applications.Deep learning(DL)is a data-driven technology that has been used to expand the limits of optical microscopy.In this study,we propose a deep neural network based on multi-level wavelet and attention mechanism(MWAM)for SIM.Our results show that the MWAM network can extract high-frequency information contained in SIM raw images and accurately integrate it into the output image,resulting in superior SR images compared to those generated using wide-field images as input data.We also demonstrate that the number of SIM raw images can be reduced to three,with one image in each illumination orientation,to achieve the optimal tradeoff between temporal and spatial resolution.Furthermore,our MWAM network exhibits superior reconstruction ability on low-SNR images compared to conventional SIM algorithms.We have also analyzed the adaptability of this network on other biological samples and successfully applied the pretrained model to other SIM systems. 展开更多
关键词 Super-resolution reconstruction multi-level wavelet packet transform residual channel attention selective kernel attention
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An Expert System to Detect Political Arabic Articles Orientation Using CatBoost Classifier Boosted by Multi-Level Features
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作者 Saad M.Darwish Abdul Rahman M.Sabri +1 位作者 Dhafar Hamed Abd Adel A.Elzoghabi 《Computer Systems Science & Engineering》 2024年第6期1595-1624,共30页
The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orient... The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orientation detection.Political articles(especially in the Arab world)are different from other articles due to their subjectivity,in which the author’s beliefs and political affiliation might have a significant influence on a political article.With categories representing the main political ideologies,this problem may be thought of as a subset of the text categorization(classification).In general,the performance of machine learning models for text classification is sensitive to hyperparameter settings.Furthermore,the feature vector used to represent a document must capture,to some extent,the complex semantics of natural language.To this end,this paper presents an intelligent system to detect political Arabic article orientation that adapts the categorical boosting(CatBoost)method combined with a multi-level feature concept.Extracting features at multiple levels can enhance the model’s ability to discriminate between different classes or patterns.Each level may capture different aspects of the input data,contributing to a more comprehensive representation.CatBoost,a robust and efficient gradient-boosting algorithm,is utilized to effectively learn and predict the complex relationships between these features and the political orientation labels associated with the articles.A dataset of political Arabic texts collected from diverse sources,including postings and articles,is used to assess the suggested technique.Conservative,reform,and revolutionary are the three subcategories of these opinions.The results of this study demonstrate that compared to other frequently used machine learning models for text classification,the CatBoost method using multi-level features performs better with an accuracy of 98.14%. 展开更多
关键词 Political articles orientation detection CatBoost classifier multi-level features context-based classification social networks machine learning stylometric features
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view
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作者 Wei Wang Jiaqi Liu +2 位作者 Shiyao Lin Baokui Geng Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期211-221,共11页
In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated... In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets. 展开更多
关键词 Integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function command filtered backstepping control Nonlinear adaptive control Extended state observer
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Construction of a Multi-Level Strategic System for Cultivating Cultural Industry Management Talents in Colleges and Universities
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作者 Zhenzhen Hu Tao Zhou 《Journal of Contemporary Educational Research》 2024年第10期75-82,共8页
Through SWOT(strengths,weaknesses,opportunities,and threats)and PEST(political,economic,social,and technological)analysis,this study discusses the construction of a multi-level strategic system for the cultivation of ... Through SWOT(strengths,weaknesses,opportunities,and threats)and PEST(political,economic,social,and technological)analysis,this study discusses the construction of a multi-level strategic system for the cultivation of cultural industry management talents in colleges and universities.First of all,based on SWOT analysis,it is found that colleges and universities have rich educational resources and policy support,but they face challenges such as insufficient practical teaching and intensified international competition.External opportunities come from the rapid development of the cultivation of cultural industry management talents and policy promotion,while threats come from global market competition and talent flow.Secondly,PEST analysis reveals the key factors in the macro-environment:at the political level,the state vigorously supports the cultivation of cultural industry management talents;at the economic level,the market demand for cultural industries is strong;at the social level,the public cultural consumption is upgraded;at the technological level,digital transformation promotes industry innovation.On this basis,this paper puts forward a multi-level strategic system covering theoretical education,practical skill improvement,interdisciplinary integration,and international vision training.The system aims to solve the problems existing in talent training in colleges and universities and cultivate high-quality cultural industry management talents with theoretical knowledge,practical skills,and global vision,so as to adapt to the increasingly complex and diversified cultural industry management talents market demand and promote the long-term development of the industry. 展开更多
关键词 Cultural industry management talents Personnel training multi-level strategic system
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基于反射的Command模式实现Undo/Redo 被引量:2
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作者 张兴亮 《计算机应用》 CSCD 北大核心 2010年第A01期233-234,共2页
针对经典Command模式在实现Undo/Redo功能时的两个缺陷,提出了基于反射的Command模式实现Undo/Redo的设计思路和实现方法,给出了该方法的数据模型,说明了事务处理的过程。
关键词 反射 command模式 设计模式 UNDO/REDO
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基于Command and Control通信信道流量属性聚类的僵尸网络检测方法 被引量:9
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作者 苏欣 张大方 +2 位作者 罗章琪 曾彬 黎文伟 《电子与信息学报》 EI CSCD 北大核心 2012年第8期1993-1999,共7页
僵尸网络(Botnet)是一种从传统恶意代码形态进化而来的新型攻击方式,为攻击者提供了隐匿、灵活且高效的一对多命令与控制信道(Command and Control channel,C&C)机制,可以控制大量僵尸主机实现信息窃取、分布式拒绝服务攻击和垃圾... 僵尸网络(Botnet)是一种从传统恶意代码形态进化而来的新型攻击方式,为攻击者提供了隐匿、灵活且高效的一对多命令与控制信道(Command and Control channel,C&C)机制,可以控制大量僵尸主机实现信息窃取、分布式拒绝服务攻击和垃圾邮件发送等攻击目的。该文提出一种与僵尸网络结构和C&C协议无关,不需要分析数据包的特征负载的僵尸网络检测方法。该方法首先使用预过滤规则对捕获的流量进行过滤,去掉与僵尸网络无关的流量;其次对过滤后的流量属性进行统计;接着使用基于X-means聚类的两步聚类算法对C&C信道的流量属性进行分析与聚类,从而达到对僵尸网络检测的目的。实验证明,该方法高效准确地把僵尸网络流量与其他正常网络流量区分,达到从实际网络中检测僵尸网络的要求,并且具有较低的误判率。 展开更多
关键词 网络检测 聚类 僵尸网络检测 命令与控制信道 流量属性
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Multi-level access control model for tree-like hierarchical organizations
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作者 於光灿 李瑞轩 +3 位作者 卢正鼎 Mudar Sarem 宋伟 苏永红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期393-396,共4页
An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning secur... An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning security tags to subjects and objects is greatly simplified.The interoperation among different departments is implemented through assigning multiple security tags to one post, and the more departments are closed on the organization tree,the more secret objects can be exchanged by the staff of the departments.The access control matrices of the department,post and staff are defined.By using the three access control matrices,a multi granularity and flexible discretionary access control policy is implemented.The outstanding merit of the BLP model is inherited,and the new model can guarantee that all the information flow is under control.Finally,our study shows that compared to the BLP model,the proposed model is more flexible. 展开更多
关键词 multi-level access control hierarchical organization multiple security tags
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MVC与COMMAND设计模式的应用 被引量:1
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作者 杨小姝 高娇 杨志东 《河北北方学院学报(自然科学版)》 2006年第4期59-63,共5页
通过实现“模拟银行”转帐功能,详细阐述了在JSP与Servlet技术开发中,对MVC与COM-MAND设计模式的使用.
关键词 MVC command 设计模式 JSP SERVLET
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广灭灵(Command)防除大豆田杂草试验 被引量:1
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作者 张文凤 何庸 《杂草科学》 1989年第1期10-13,共4页
广灭灵通用名为Fenoxan,化学名为2—(2—氯苯)甲基—4,4—二甲基—3—异(口恶)唑烷酮。系美国FMC公司近年开发的一种选择性除草剂。受农业部农药检定所委托,1986~1988年我所进行了广灭灵防除大豆杂草的试验。现将结果报告如下。一、材... 广灭灵通用名为Fenoxan,化学名为2—(2—氯苯)甲基—4,4—二甲基—3—异(口恶)唑烷酮。系美国FMC公司近年开发的一种选择性除草剂。受农业部农药检定所委托,1986~1988年我所进行了广灭灵防除大豆杂草的试验。现将结果报告如下。一、材料与方法 (一)供试药剂:72%广灭灵乳油;48%氟乐灵乳油(意大利产);70%赛克津可湿粉(西德拜耳公司产)。 (二)试验处理: 1.播前处理: 展开更多
关键词 广灭灵 command 杂草防除 大豆田 氟乐灵乳油 选择性除草剂 除草效果 播前处理 下茬作物 防除效果
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应用Command模式实现短信互动程序设计 被引量:1
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作者 王建宣 张严林 《计算机时代》 2008年第12期51-52,共2页
介绍一种采用XML描述流程,应用Command模式实现短信互动流程的程序设计方法。详细介绍了如何用XML描述流程以及如何用Command模式实现自定义流程的执行。该设计方法使维护人员只需修改XML文件就可以自动实现流程变更。
关键词 command模式 XML 短信互动 流程
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使用Command设计模式实现编辑器的RedoUndo 被引量:3
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作者 侯军伟 康慕宁 《科学技术与工程》 2010年第4期1033-1036,共4页
设计模式是对于共性问题成功的解决方案,采用设计模式可以减少系统设计的复杂度,提高系统开发的效率[1]。Command模式是常用的23种设计模式中的一种。Command模式是将"动作"进行抽象,将与动作有关的所有信息进行封装,从而实... 设计模式是对于共性问题成功的解决方案,采用设计模式可以减少系统设计的复杂度,提高系统开发的效率[1]。Command模式是常用的23种设计模式中的一种。Command模式是将"动作"进行抽象,将与动作有关的所有信息进行封装,从而实现调用操作的对象与知道如何实现该操作的对象解耦。RedoUndo是现代编译器中必不可少的一种工具,可以提高工作效率。详细探讨了如何使用Command模式实现RedoUndo以及各种扩展。 展开更多
关键词 设计模式 command模式 RedoUndo
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VB中ADO对象的Command对象用法探讨
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作者 牟瑛 《福建电脑》 2006年第3期174-175,共2页
本文阐述ADO对象的Command对象用法,并给出编程实例。
关键词 ADO command 存储过程 记录集
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Shape retrieval using multi-level included angle functions-based Fourier descriptor 被引量:1
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作者 徐国清 穆志纯 徐烨 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期22-26,共5页
An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation tran... An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation translation and scaling are the intrinsic properties of the MIAFs.For each contour point the multi-level included angles are obtained based on the paired line segments derived from unequal-arc-length partitions of contour.And a Fourier descriptor derived from multi-level included angle functions MIAFD is presented for efficient shape retrieval.The proposed descriptor is evaluated with the standard performance evaluation method on three shape image databases the MPEG-7 database the Kimia-99 database and the Swedish leaf database. The experimental results of shape retrieval indicate that the MIAFD outperforms the existing Fourier descriptors and has low computational complexity.And the comparison of the MIAFD with other shape description methods also shows that the proposed descriptor has the highest precision at the same recall value which verifies its effectiveness. 展开更多
关键词 shape description image retrieval multi-level included angle function Fourier descriptor
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COMMAND.COM命令处理文件的结构与使用
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作者 朱猛 《电脑知识》 1996年第2期7-8,共2页
众所周知,DOS是个人计算机的核心软件,是计算机硬件资源和软件资源的管家,而命令处理文件COMMAND.
关键词 DOS 命令处理文件 command.COM
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基于MVC和Command设计模式的线号打印机软件系统开发 被引量:1
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作者 赵学芳 林湧涛 《计算机与现代化》 2009年第7期130-132,共3页
分析线号打印机软件需求和MVC框架设计的优势,充分利用Command设计模式的灵活性,将线号打印机的特定内容通过预定义的标记来适应不同的需求,由此提出一个基于MVC的软件系统。该系统为用户提供良好的交互界面,给线号打印机应用提供了有... 分析线号打印机软件需求和MVC框架设计的优势,充分利用Command设计模式的灵活性,将线号打印机的特定内容通过预定义的标记来适应不同的需求,由此提出一个基于MVC的软件系统。该系统为用户提供良好的交互界面,给线号打印机应用提供了有力的支持。 展开更多
关键词 线号打印机 MVC command设计模式 交互界面
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Observer模式与Command模式在条码采集系统中的应用研究 被引量:2
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作者 焦付强 闵联营 +1 位作者 赵辉 裴朝举 《电脑知识与技术》 2009年第2期1002-1003,1008,共3页
结合条码采集系统的设计与开发,探讨了设计模式中的Observer模式与Command模式,结果表明:使用Observer模式进行数据管理,使用Command模式进行功能管理,可以增强系统代码的重用性、灵活性和模块化,提高了系统开发效率。
关键词 设计模式 OBSERVER模式 command模式
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KBA Commander宽幅轮转胶印机版卡机构检修
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作者 王淑海 丁勇 《印刷技术》 2021年第1期43-46,共4页
KBA Commander宽幅轮转胶印机版卡机构在进口设备中比较少见,其独特的设计理念会给每个检修者留下深刻的印象。KBA Commander宽幅轮转胶印机版卡机构由版卡、定位销、间隔挡块、开夹气囊、气囊及衬层钢片、气阀等部件组成,在设备运行过... KBA Commander宽幅轮转胶印机版卡机构在进口设备中比较少见,其独特的设计理念会给每个检修者留下深刻的印象。KBA Commander宽幅轮转胶印机版卡机构由版卡、定位销、间隔挡块、开夹气囊、气囊及衬层钢片、气阀等部件组成,在设备运行过程中遇到的较多故障是连接开夹气囊的气管因老化而出现破裂漏气,导致版卡打不开。一旦遇到这种情况,对大多数检修者来说就是一种煎熬!本文,笔者根据多年来的实际操作,分享自己的感受和解决技巧,供同仁参考借鉴。 展开更多
关键词 轮转胶印机 进口设备 commandER 定位销 宽幅 解决技巧 气囊 设计理念
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Adaptive optimization of agile organization of command and control resource 被引量:8
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作者 Yang Chunhui Liu Junxian +1 位作者 Chen Honghui Luo Xueshan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期558-564,共7页
Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put for... Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put forward by analyzing the interrelating concept and research. The model takes the adaptive process as a multi-stage decision making problem. The 2-phases method is presented to calculate the model, which obtains the related parameters by running the colored Petri net (CPN) model of AOC2R and then searches for the result by ant colony optimization (ACO) algorithm integrated with genetic optimization techniques. The simulation results demonstrate that the proposed algorithm greatly improves the performance of AOC2R. 展开更多
关键词 command and control organization adaptive optimization of organization dynamic-window-search ant colony optimization 3-phase organizational design.
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Seasonal Dynamics of Nitrogen and Phosphorus in Water and Sediment of A Multi-level Ditch System in Sanjiang Plain,Northeast China 被引量:6
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作者 GUO Le MA Keming 《Chinese Geographical Science》 SCIE CSCD 2011年第4期437-445,共9页
The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasona... The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasonal dynamics of nitrogen (N) and phosphorus (P) transportation in the ditch system and the role of different ditch size is thus crucial for water pollution control of the rivers in the Sanjiang Plain.In this study,an investigation was conducted in the Nongjiang watershed of the Sanjiang Plain to study the nutrient variation and the correlation between water and sediments in the ditch system in terms of ditch level.Water and sediments samples were collected in each ditch level in growing season at regular intervals (once per month),and TN,NO 3--N,NH 4+-N,TP,and PO 4 3--P were analyzed.The results show that nutrient contents in water were higher in June and July,especially in July,the contents of TN and TP were 3.21mg/L and 0.84mg/L in field ditch,4.04mg/L and 1.06mg/L in lateral ditch,2.46mg/L and 0.70mg/L in branch ditch,1.92mg/L and 0.63mg/L in main ditch,respectively.In August and September,the nutrient contents in the water were relatively lower.The peak value of nutrient in ditch water had been moving from the field ditch to the main ditch over time,showing a remarkable impact of ditch system on river water environment.The nutrient transfer in ditch sediments could only be found in rainfall season.Nutrient contents in ditch sediment had effect on that in ditch water,but nutrients in ditch water and sediments had different origination.Ditch management in terms of the key fac-tors is hence very important for protecting river water environment. 展开更多
关键词 multi-level ditch system nitrogen PHOSPHORUS spatio-temporal variation drainage water sediment
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