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泥沙研究进展综述

泥沙研究 1999年第1期24卷 74-80页

作者：曾庆华泥沙专业委员会

我国河流众多，流域面积大于１００ｋｍ２的有５万多条，流域面积在１０００ｋｍ２以上的河流有１５００多条。全国水利资源丰富，正常年迳流量达２７１１５亿ｍ３，水能蕴藏量为５８亿千瓦。在我国江河治理中，一个十分突出的问题就... 详细信息

我国河流众多，流域面积大于１００ｋｍ２的有５万多条，流域面积在１０００ｋｍ２以上的河流有１５００多条。全国水利资源丰富，正常年迳流量达２７１１５亿ｍ３，水能蕴藏量为５８亿千瓦。在我国江河治理中，一个十分突出的问题就是泥沙问题，大江大河流域内水土流失...

关键词：泥沙研究进展河流泥沙输沙量

基于系统构型替换的固冲发动机故障模式半实物仿真

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国防科技大学学报 2019年第4期41卷 79-85页

作者：王安曾庆华周宇宸国防科技大学空天科学学院湖南长沙410073 中山大学航空航天学院广东广州510006

为全面快速验证冲压发动机的故障检测算法,基于构型替换建立了能模拟多种固冲发动机故障的仿真验证平台。基于此平台,搭建了发动机点火故障模型、压强传感器故障模型、设备接口模型,以及与真实控制器中检测算法具有相同外部接口和系统... 详细信息

为全面快速验证冲压发动机的故障检测算法,基于构型替换建立了能模拟多种固冲发动机故障的仿真验证平台。基于此平台,搭建了发动机点火故障模型、压强传感器故障模型、设备接口模型,以及与真实控制器中检测算法具有相同外部接口和系统构型的故障检测算法模型等。通过系统构型的切换,将同一个故障模式注入故障检测算法模型和真实发动机系统,并通过对比同一组故障模式下故障检测模型检测结果与发动机控制系统检测结果,来对发动机控制器中的故障检测算法进行快速验证。以无喷管助推器点火的检测为例,讲述了该方法的建模、实验验证及分析过程,此外,该方法还能应用到无喷管助推器关机、进气道前后堵盖打开、燃气发生器点火、燃气流量容错控制等多个故障模式的仿真模拟与验证,具有很强的通用性,能大大地降低控制系统开发与验证的时间成本,具有很强的应用价值。

关键词：故障仿真模拟固冲发动机系统构型替换发动机故障建模

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基于时间价值的交通出行方式选择行为研究

管理工程学报 2020年第3期34卷 142-150页

作者：宗刚曾庆华魏素豪北京工业大学经济与管理学院北京100124 中国人民大学农业与农村发展学院北京100872

通勤出行是城市居民最基本和最重要的出行目的,通勤出行时间价值是评价通勤出行者对交通方式选择的重要参数之一,以累积前景理论为基础,将通勤出行时间价值引入广义出行成本函数中,以权重函数和改进的广义出行成本函数作为交通方式选择... 详细信息

通勤出行是城市居民最基本和最重要的出行目的,通勤出行时间价值是评价通勤出行者对交通方式选择的重要参数之一,以累积前景理论为基础,将通勤出行时间价值引入广义出行成本函数中,以权重函数和改进的广义出行成本函数作为交通方式选择模型的依据,并在模型中自定义广义出行成本参考点,选择累积前景值最大的前景作为出行者最优决策。分别基于“期望效用最大化理论”和“累积前景理论”对通勤出行者在三种不同出行场景下进行仿真模拟,研究最优交通方式选择行为。研究结果表明:期望效用理论框架下,通勤出行者的交通方式选择行为不受出行场景的影响,累积前景理论更适用于出行方式选择行为的研究。构建以通勤出行时间价值为核心变量的交通方式选择模型,可帮助通勤出行者选择合理的交通方式,并为政府及相关部门制定交通管理规划和实施缓解交通拥堵政策提供依据。

关键词：通勤出行时间价值交通方式累积前景理论

城市多级公交线路优化设计研究——来自于北京城市副中心的案例

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中国管理科学 2024年第9期32卷 121-130页

作者：曾庆华宗刚北京物资学院经济学院北京101149 北京工业大学经济与管理学院北京100124

日益增长的城市道路交通需求带来的交通拥堵和大气污染问题,已经成为近些年受到广泛关注、亟待解决的问题。本文以北京市通州区居民公交出行相关的调研数据为样本,在公交线路“异质性”假设的基础上,将轴辐式网络设计引入到城市公交线... 详细信息

日益增长的城市道路交通需求带来的交通拥堵和大气污染问题,已经成为近些年受到广泛关注、亟待解决的问题。本文以北京市通州区居民公交出行相关的调研数据为样本,在公交线路“异质性”假设的基础上,将轴辐式网络设计引入到城市公交线路优化问题中,验证居民出行距离与模拟电子云分布和双阶威布尔分布相吻合。提出宏观层面的公交总费用概念,构建轴辐式多级公交线路配置模型。测算不同级别公交线路的需求量和供给量,以及居民的优势出行距离,检验居民公交出行需求与公交系统提供的运力间的错配问题。研究发现:通州区轴线和辅线的居民出行需求量大于相应等级线路的公交供给量,存在供不应求的错配问题;支线居民公交出行需求量小于该等级的公交供给量,存在供过于求的错配问题。文章提出相应的对策建议,以期为交通运输部门为推进碳中和目标的实现,对降污减排和缓解交通拥堵等问题进行政策制定提供科学的理论依据。

关键词：多级公交线路优化轴辐式网络缓解交通拥堵供需均衡资源配置

Leaching kinetics of ionic rare-earth in ammonia-nitrogen wastewater system added with impurity inhibitors

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Journal of Rare Earths 2014年第12期32卷 1175-1183页

作者：邱廷省朱冬梅方夕辉曾清华高广阔朱华磊 Faculty of Resource and Environmental Engineering Jiangxi University of Science and Technology SLon Magnetic Separator Ltd. School of Computing Engineering and Mathematics University of Western Sydney

Ammonia-nitrogen wastewater is produced during the dressing and smelting process of rare-earth *** wastewater includes a very high concentration of NH4＋, as well as other ions（e.g., NH4＋, RE3＋, Al3＋, Fe3＋, Ca2＋, Cl–, and Si O32–） with a p H of 5.4–*** direct discharge will pollute, yet it can be recycled and used as a leaching reagent for ionic rare-earth *** this study, leaching kinetics studies of both rare earth ions and impurity ion Al3＋ were conducted in the ammonia-nitrogen wastewater system with the aid of impurity *** showed that the leaching process of rare-earth followed the internal diffusion kinetic *** the temperature was 298 K and the concentration of NH4＋ was 0.3 mol/L, the leaching reaction rate constant of ionic rare-earth was 1.72 and the apparent activation energy was 9.619 k J/*** leaching rate was higher than that of conventional leaching system with ammonium sulfate, which indicated that ammonia-nitrogen wastewater system and the addition of impurity inhibitors could promote ionic rare-earth *** leaching kinetic process of impurity Al3＋ did not follow either internal diffusion kinetic model or chemical reaction control, but the hybrid control model which was affected by a number of process ***, during the industrial production the leaching of impurity ions could be reduced by increasing the concentration of impurity inhibitors, reducing the leaching temperature to a proper range, accelerating the seepage velocity of leaching solution, or increasing the leaching rate of rare earths.

关键词： ionic rare-earth ammonia-nitrogen wastewater impurity inhibitor leaching kinetics

SEDIMENT　TRANSPORT　BEHAVIOR　FOR　DIFFERENT　SIZE　GROUPS　IN　THE　LOWER　YELLOW　RIVER

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International Journal of Sediment Research 1995年第3期 51-68页

作者： ZHOU Wenhao zeng qinghua ZHAO Huaxia and CHEN Jianguo China Institute of Water Resources and Hydropower Research

ＳＥＤＩＭＥＮＴＴＲＡＮＳＰＯＲＴＢＥＨＡＶＩＯＲＦＯＲＤＩＦＦＥＲＥＮＴＳＩＺＥＧＲＯＵＰＳＩＮＴＨＥＬＯＷＥＲＹＥＬＬＯＷＲＩＶＥＲＺＨＯＵＷｅｎｈａｏ；ＺＥＮＧＱｉｎｇｈｕａ；ＺＨＡＯＨｕａｘｉａａｎｄＣＨＥＮ...

ＳＥＤＩＭＥＮＴＴＲＡＮＳＰＯＲＴＢＥＨＡＶＩＯＲＦＯＲＤＩＦＦＥＲＥＮＴＳＩＺＥＧＲＯＵＰＳＩＮＴＨＥＬＯＷＥＲＹＥＬＬＯＷＲＩＶＥＲＺＨＯＵＷｅｎｈａｏ；ＺＥＮＧＱｉｎｇｈｕａ；ＺＨＡＯＨｕａｘｉａａｎｄＣＨＥＮＪｉａｎｇｕｏ（ＴｈｅＥｎｇｌｉｓ...

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Calibration Method for LiDAR Cameras in Natural Dynamic Environments

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Calibration Method for LiDAR Cameras in Natural Dynamic Envi...

第十四届中国卫星导航年会

作者： Sheng Hong qinghua zeng Yineng Li Xiaorong Sun Jizhou Lai College of Automation Engineering Nanjing University of Aeronautics & Astronautics

The external calibration of sensors has a crucial impact on the accuracy of subsequent integrated navigation. In this paper, an automatic calibration method for a lidar/RGB camera system is proposed under dynamic environmental disturbances without any target present. The theoretical analysis focuses on the characteristics and limitations of edge features, as well as their influence on calibration accuracy. In terms of implementation, the measurement principles of the lidar and camera are analyzed. A projection-based method for dynamic point rejection of the lidar is proposed, and the external calibration of the sensor is achieved using a Bundle Adjustment optimization method based on the edge extraction results of point clouds and images. Since edge features are abundant in natural scenes, the proposed method is evaluated in an indoor scene with dynamic environmental disturbances. The results demonstrate that the proposed method has higher robustness and accuracy than conventional algorithms, achieving good calibration results in the presence of dynamic environmental disturbances.

关键词：

Smartphone heading correction method based on LSTM Neural Network

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Smartphone heading correction method based on LSTM Neural Ne...

第十三届中国卫星导航年会

作者： Yan Huang qinghua zeng Qiyao Lei Zhijun Chen Kecheng Sun College of Automation Engineering Nanjing University of Aeronautics ＆ Astronautics

The error of heading estimation is the main factor that affects the accuracy of the navigation and positioning of the smartphone based on the pedestrian dead reckoning. In this paper, aiming at the heading error caused by gyroscope drift in smartphone pedestrian heading estimation, a smartphone heading error compensation model based on Long Short-Term Memory network（LSTM） is proposed. Due to the low precision of inertial devices in smartphones, the direct integration will lead to cumulative errors that the neural network can correct. Considering that the calculation method of inertial navigation is dead reckoning, the data time of the preceding and following moments is related. And LSTM performs better in the long sequence than the ordinary neural network, so this paper uses a dynamic capture system to get high-precision attitude information. The LSTM actual value of the neural network training establishes the direction error correction model of smartphones. By comparing the proposed algorithm with traditional quaternion heading estimation methods, the error correction model presented in this paper can effectively suppress the influence of gyroscope drift. The result is better,which can meet the basic needs of pedestrian navigation and positioning.

关键词： Pedestrian dead reckoning Heading correction Smartphone Netural network

An Auxiliary Heterogeneous Visual Localization Algorithm Based on Improved Hough Transform Line Matching

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An Auxiliary Heterogeneous Visual Localization Algorithm Bas...

第十三届中国卫星导航年会

作者： Yixue Luo qinghua zeng Wenqi Qiu Yineng Li Kecheng Sun College of Automation Engineering Nanjing University of Aeronautics and Astronautics Key Laboratory of the MIIT advanced aircraft navigation control and health management Jiangsu University Collaborative Innovation Center for satellite communication and navigation

With the increasing demand for all-weather,uninterrupted aviation missions,heterogeneous visual navigation and positioning technology based on visible images and infrared images has been developed,and the key technology of heterogeneous image matching has become a research *** to the different imaging mechanisms of heterogeneous images,it is difficult to directly apply the homogeneous image matching algorithm to heterogeneous images,and the feature extraction accuracy of algorithms based on line segment structure such as Hough transform needs to be ***,an improved Hough transform line matching algorithm to assist heterogeneous visual positioning is proposed in this *** on the heterogeneous image obtained by different optical sensors,the adaptive Canny operator of the improved maximum inter-class variance method is used for edge *** detected edge binary image is processed by Hough transform,and the line features in the heterogeneous images are extracted for *** experimental results show that the Hough transform line matching algorithm using the improved Canny operator has a line feature detection accuracy of 66%,which is 74.23% higher than the traditional Hough transform line matching *** number of correctly matched line features of the proposed algorithm is better than that of the traditional algorithm,which can provide ideas for the pose calculation based on heterogeneous *** running time of the proposed algorithm is better than that of the traditional Hough transform line matching algorithm,and the total time is reduced by 46.62%.

关键词： Heterogeneous Image Hough Transform Canny Operator Feature Matching Visual Positioning