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Impacts of dams and land-use changes on hydromorphology of braided channels in the Lhasa River of the Qinghai-Tibet Plateau,China

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International Journal of Sediment Research 2022年第2期37卷 214-228页

作者： Yuchi You zhiwei li Peng Gao Tiesong Hu School of Hydraulic Engineering Changsha University of Science & Technology State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Department of Geography and the Environment Syracuse University

Among braided rivers developed on the Qinghai-Tibet Plateau of China at very high elevations(>3,500 m),the middle and lower reaches of the Lhasa River have been affected by comprehensive human activities mainly involving dam construction,urbanization,farming,afforestation,and *** the current study,the impacts of these human activities on hydrology and morphology of the four braided reaches downstream of a cascaded of two dams are *** study period was divided into 1985-2006(P1),2006-2013(P2),and 2013-2019(P3),representing the natural and changed flow regimes by *** available daily discharge data at two stations within the four braided reaches,dam-induced hydrological alteration was analyzed based on the indicators of hydrologic alteration and range of variability approach and key discharge proxies were *** sensed images also were selected in the three periods and morphological metrics extracted from them were compared for the four reaches among these *** hydrological regimes were found for only two *** total channel width(Wc) and braiding intensity(BIt) followed different temporal trends among the four *** average shift rates of the main channel in the four reaches were higher in the short(P2-P3) than in the long(P1-P2 and P1-P3) *** longitudinal changes of Wcand the number of channels did not have any identifiable trend among the four *** linking the morphological changes to quantified spatial and temporal patterns of various human activities,it was found that(1) the two dams had insignificant impact on channel morphology,suggesting that the studied braided river might have a short relaxation time and(2) the evolutional trajectories of morphological changes in most of the four reaches were similar,suggesting that temporal trends of morphological changes due to complex human activities are not affected by the different physiographic settings of the *** exploitati

关键词： Braided river Channel morphology Human activities Dam impact

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Two-dimensional modeling of channel evolution under the influence of large-scale river regulation works

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International Journal of Sediment Research 2022年第4期37卷 424-434页

作者： Meirong Zhou Junqiang Xia Shanshan Deng zhiwei li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

In the middle and lower reaches of alluvial rivers, various kinds of river regulation projects affecting natural channel evolution often are distributed due to the requirements of flood control, navigation,and channel stability. However, the influence of large-scale river regulation works on fluvial processes is not fully known. Therefore, a two-dimensional(2D) morphodynamic model has been improved to address this problem. The new detailed procedure is presented in this paper:(i) First, each node in the study domain was labeled using a specified point code to distinguish the zones with or without regulation works; and(ii) second, a 2D model was improved to consider the effect of river regulation works. In the refined model, the modules of sediment transport and bed deformation were treated separately in different zones. In the unprotected zones, both bed deposition and erosion were likely to occur. In the protected zones, bed erosion could not occur owing to the protection provided by the river regulation works, unless there was a deposition layer newly formed over the previous simulation periods. The observed data of the years 2004 and 2008 were used to calibrate and verify the improved 2D morphodynamic model which was applied in a 68-km-long reach of the Middle Yangtze River. Satisfactory results were obtained indicating that the improved model can better simulate the process of sediment transport and the morphology adjustment in three central bars in the study reach.

关键词： Two-dimensional model River regulation works Channel evolution Central bar Middle Yangtze River

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Modelling of cantilever bank failure for peat-type meander bends in the source region of the Yellow River

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International Journal of Sediment Research 2023年第3期38卷 421-431页

作者： Hanyuan Yang zhiwei li Yongjun Lu Huaixiang liu liqin Zuo State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Yangtze Institute for Conservation and Development

Bank retreat involving a combination of fluvial erosion and bank collapse has been found to be a major contributor to sediment transport, lateral migration, and planform evolution of meandering *** studies have largely examined the general mechanism of cantilever bank failure. However, the composite process of beam(toppling) failure caused by shear failure of the lower part composed of noncohesive soil remains poorly understood. The current paper investigates the diversity and coupling of this collapse process, which is the dominant pattern in the peat-type meandering rivers of the Zoige River basin in the source region of the Yellow River. For this purpose, morphologic and hydraulic measurements were done in the summers of 2016 and 2017. Moreover, a combined method of a theoretical model and numerical simulation was developed to be applied for a continuous meandering channel in the Zoige basin, focusing in particular on five typical cross sections of a highly convoluted bend approaching neck cutoff. Specifically, the theoretical model evaluating the stability of overhanging riverbank was based on static equilibrium theory considering the interaction between composite soil layers. In addition, the Bank Stability and Toe Erosion Model was used to simulate the retreat process of the silt layer based on field measurements including bank morphology, soil composition, and hydrological parameters. Thus, a calculation method for the occurrence of cantilever beam failure in the flood period is proposed, and temporal change and spatial variability in bank profiles caused by three consecutive failures is estimated at the five sections. Satisfactory results showed a relatively close agreement between the calculations and field measurements in terms of the width of the overhanging arms and the dimensions of the slump blocks.

关键词： River bends Bank erosion Cantilever failure Numerical simulation Meandering river

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探头式共聚焦激光显微内镜量化指标诊断幽门螺杆菌相关萎缩性胃炎的临床研究

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中华消化内镜杂志 2024年第6期41卷 465-471页

作者：陈佳颖吴迪党彤汤泊夫刘琳贾语婧李志伟包头医学院第二附属医院消化内科包头014030 包头医学院第一附属医院重症医学科包头014010

目的量化探头式共聚焦激光显微内镜(probe-based confocal laser endomicroscopy,pCLE)诊断幽门螺杆菌相关萎缩性胃炎(***-associated chronic atrophic gastritis,HpCAG)的诊断指标,并评价诊断效能。方法研究分为2个阶段:第1阶段前瞻性纳入2021年11月至2022年9月在包头医学院第二附属医院行胃镜检查及内镜下活检并行13C呼气试验的患者作为研究对象,离线视频采用Image J图像分析软件测量pCLE视野中的毛细血管直径(capillary diameter,CD)、细胞间距(cells spacing,CS)、腺体间距(gland spacing,GS)、腺体面积(gland area,GA)这4个指标,通过分析受试者工作特征(receiver operating characteristic,ROC)曲线下面积,建立pCLE下量化指标诊断HpCAG的标准;第2阶段回顾性纳入2021年10月至2022年10月间在包头医学院第二附属医院行pCLE检查及13C呼气试验的病例,剔除与第1阶段数据重合的病例,试验采用单盲法,内镜医师和病理医师对彼此的诊断结果不知情,pCLE的诊断根据第1阶段获得的标准进行,统计分析pCLE诊断与组织病理学+13C呼气试验结果的一致性。结果第1阶段招募到35例患者共计191块标本入组,根据内镜活检病理结果及13C呼气试验结果将患者及胃黏膜标本分为4组,即幽门螺杆菌(Helicobacter pylori,HP)阳性萎缩性胃炎组(n=59)、HP阳性非萎缩性胃炎组(n=52)、HP阴性萎缩性胃炎组(n=40)、HP阴性非萎缩性胃炎组(n=40)。ROC曲线分析结果显示:在HP阳性患者中,GS区分慢性萎缩性胃炎与非萎缩性胃炎胃黏膜的最佳临界值为29.68μm,在4个参数中ROC曲线下面积最大;在HP阴性患者中,GS区分慢性萎缩性胃炎与非萎缩性胃炎胃黏膜的最佳临界值为23.57μm,在4个参数中ROC曲线下面积最大;在非萎缩性胃炎患者中,GS区分HP阳性与HP阴性胃黏膜的最佳临界值为20.57μm,在4个参数中ROC曲线下面积最大;在慢性萎缩性胃炎患者中,CD、CS、GS、GA区分HP阳性与HP阴性胃黏膜的最佳临界值分别为13.23μm、1.38μm、34.03μm、6066.5μm^(2),ROC曲线下面积分别为0.608、0.888、0.849、0.900。最终选择GS区分HpCAG与非HpCAG胃黏膜,最佳临界值为31.71μm,但考虑到难以通过图像下方的标尺测量31.71μm的距离,故将临界值改为30μm,因此将GS>30μm作为pCLE下HpCAG的诊断标准,此时诊断的敏感度和特异度分别为91.5%和76.0%。第2阶段观察了80例患者的224块标本:pCLE(GS>30μm)诊断HpCAG的敏感度、特异度、阳性预测值、阴性预测值和准确率分别为96.5%(164/170)、88.9%(48/54)、96.5%(164/170)、88.9%(48/54)和94.6%(212/224),与组织病理学+13C呼气试验的诊断一致性极好(Kappa=0.854)。结论pCLE下可以实现胃黏膜微观结构的定量监测,量化后的指标有助于提高HpCAG诊断的准确率。

关键词：胃炎,萎缩性幽门螺杆菌相关萎缩性胃炎探头式共聚焦激光显微内镜量化标准

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Self‑supervised zero‑shot dehazing network based on dark channel prior

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Frontiers of Optoelectronics 2023年第1期16卷 95-108页

作者： Xinjie Xiao Yuanhong Ren zhiwei li Nannan Zhang Wuneng Zhou School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China College of Information Science and Technology Donghua UniversityShanghai 201620China

Most learning-based methods previously used in image dehazing employ a supervised learning strategy,which is timeconsuming and requires a large-scale ***,large-scale datasets are difcult to ***,we propose a selfsupervised zero-shot dehazing network(SZDNet)based on dark channel prior,which uses a hazy image generated from the output dehazed image as a pseudo-label to supervise the optimization process of the ***,we use a novel multichannel quad-tree algorithm to estimate atmospheric light values,which is more accurate than previous ***,the sum of the cosine distance and the mean squared error between the pseudo-label and the input image is applied as a loss function to enhance the quality of the dehazed *** most signifcant advantage of the SZDNet is that it does not require a large dataset for training before performing the dehazing *** testing shows promising performances of the proposed method in both qualitative and quantitative evaluations when compared with state-of-the-art methods.

关键词： Image dehazing Quad-tree algorithm Self-supervised Zero-shot

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模糊积分决策级融合的空地协同目标识别研究

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火力与指挥控制 2024年第2期49卷 95-101,107页

作者：郭宇强陶思源郭俊文卢志刚李志伟北方自动控制技术研究所太原030006 智能信息控制技术山西省重点实验室太原030006 中国航天空气动力技术研究院北京100074

针对单独使用无人机或无人车对目标区域侦察识别效率低、虚警率高等局限性问题,分析了多种决策级信息融合的方法,提出了基于模糊积分改进的决策级空地信息融合目标识别方法,将空地协同探测的目标类型、位置、威胁度、毁伤程度等信息进... 详细信息

针对单独使用无人机或无人车对目标区域侦察识别效率低、虚警率高等局限性问题,分析了多种决策级信息融合的方法,提出了基于模糊积分改进的决策级空地信息融合目标识别方法,将空地协同探测的目标类型、位置、威胁度、毁伤程度等信息进行融合识别并输出。仿真结果表明,该算法有效完善了目标信息,提高了目标特征信息识别准确性,降低了虚警率。

关键词：空地协同决策级融合模糊积分信息融合融合识别

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FPGA Optimized Accelerator of DCNN with Fast Data Readout and Multiplier Sharing Strategy

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Computers, Materials & Continua 2023年第12期77卷 3237-3263页

作者： Tuo Ma zhiwei li Qingjiang li Haijun liu Zhongjin Zhao Yinan Wang College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China

With the continuous development of deep learning,Deep Convolutional Neural Network(DCNN)has attracted wide attention in the industry due to its high accuracy in image *** with other DCNN hard-ware deployment platforms,Field Programmable Gate Array(FPGA)has the advantages of being programmable,low power consumption,parallelism,and low ***,the enormous amount of calculation of DCNN and the limited logic capacity of FPGA restrict the energy efficiency of the DCNN *** traditional sequential sliding window method can improve the throughput of the DCNN accelerator by data multiplexing,but this method’s data multiplexing rate is low because it repeatedly reads the data between *** paper proposes a fast data readout strategy via the circular sliding window data reading method,it can improve the multiplexing rate of data between rows by optimizing the memory access order of input *** addition,the multiplication bit width of the DCNN accelerator is much smaller than that of the Digital Signal Processing(DSP)on the FPGA,which means that there will be a waste of resources if a multiplication uses a single DSP.A multiplier sharing strategy is proposed,the multiplier of the accelerator is customized so that a single DSP block can complete multiple groups of 4,6,and 8-bit signed multiplication in ***,based on two strategies of appeal,an FPGA optimized accelerator is *** accelerator is customized by Verilog language and deployed on Xilinx *** the accelerator recognizes the CIRFAR-10 dataset,its energy efficiency is 39.98 GOPS/W,which provides 1.73×speedup energy efficiency over previous DCNN FPGA *** the accelerator recognizes the IMAGENET dataset,its energy efficiency is 41.12 GOPS/W,which shows 1.28×−3.14×energy efficiency compared with others.

关键词： FPGA accelerator DCNN fast data readout strategy multiplier sharing strategy network quantization energy efficient

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边缘计算在智慧矿山建设中的应用分析

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华北科技学院学报 2024年第1期21卷 1-11页

作者：黎冠李志伟陈浩张明月童波华北科技学院信息与控制工程学院北京东燕郊065201

为了满足智慧矿山建设的技术需求,提出了基于边缘计算的智慧矿山建设新思路。首先,从智慧矿山建设目前存在的问题入手,分析和梳理了智慧矿山建设研究现状,指出了基于云计算矿山集中式架构的不足,通过研究新一代信息技术与工业技术融合应... 详细信息

为了满足智慧矿山建设的技术需求,提出了基于边缘计算的智慧矿山建设新思路。首先,从智慧矿山建设目前存在的问题入手,分析和梳理了智慧矿山建设研究现状,指出了基于云计算矿山集中式架构的不足,通过研究新一代信息技术与工业技术融合应用,阐述了边缘计算的概念,指出了边缘计算将为智慧矿山的建设赋能。然后,介绍了边缘计算的发展历史背景、技术特点、典型架构以及发展趋势。重点分析了边缘计算应用于智慧矿山系统的优势,探讨了边缘计算赋能智慧矿山的关键技术问题,并构建了基于边缘计算的智慧矿山架构模型。与传统监测监控体系相比,基于边缘计算的体系在实时性、高效性和安全性具有一定优势。本文旨在通过对智慧矿山的边缘计算技术研究,为矿山边缘计算模型构建提供思路,为未来智慧矿山建设提供借鉴。

关键词：边缘计算智慧矿山人工智能云计算

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Predefined-time bipartite tracking consensus for second-order multi-agent systems with cooperative and antagonistic networks

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Journal of Control and Decision 2023年第2期10卷 280-292页

作者： Yuanhong Ren Zhiwen Chen Yong Ji zhiwei li School of Artificial Intelligence Application Shanghai Urban Construction Vocational CollegeShanghaiPeople’s Republic of China College of Information Science and Technology Donghua UniversityShanghaiPeople’s Republic of China School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghaiPeople’s Republic of China

This paper addresses the predefined-time bipartite tracking problem for second-order Multi-Agent Systems(MASs)with undirected signed topologies.A group of observers,which can estimate the state tracking errors for each follower in a pre-specified time,is proposed based on the time-varying *** order to deal with the uncertainties caused by the unknown disturbances and the unknown input signal of the leader,we propose a predefined-time distributed control protocol based on the sliding mode control *** addition,an auxiliary dynamic sliding variable is designed to reduce system *** prove that the two control protocols can drive the state trajectories of each follower to reach the corresponding sliding surface within a specified time,and finally ensure that the prescribed-time bipartite tracking consensus is achieved for the *** are provided to verify the proposed schemes,and the simulation results further confirm the superiority of the adaptive control protocol.

关键词： Predefined-time tracking consensus bipartite consensus multi-agent systems prescribed-time observers adaptive dynamic sliding mode control

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红色文化数字化传承服务平台设计与实现

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河南科技 2024年第12期51卷 30-34页

作者：崔嘉俊李志伟王鹏恒郑州科技学院河南郑州450064

【目的】探讨如何通过数字化技术设计和实现一个红色文化数字化传承服务平台。【方法】采用Django作为后端框架,负责处理用户请求和响应,以及与数据库的交互;采用Vue作为前端框架渲染用户的界面和交互,以及后端的通信;采用***来实现3D... 详细信息

【目的】探讨如何通过数字化技术设计和实现一个红色文化数字化传承服务平台。【方法】采用Django作为后端框架,负责处理用户请求和响应,以及与数据库的交互;采用Vue作为前端框架渲染用户的界面和交互,以及后端的通信;采用***来实现3D可视化效果。【结果】成功地设计和实现了一个红色文化数字化传承服务平台,并通过该服务平台,实现了对红色文化遗产的数字化管理、展示和保护,且为广大用户提供了便捷访问和参与红色文化遗产的途径。【结论】结果表明,红色文化数字化传承服务平台是一种有效地保护和传承红色文化的方式,可以为红色文化的保护和传承提供一些有价值的启示和建议。

关键词：红色文化数字化传承服务平台 Django框架 Vue框架 Three.js框架

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