检索结果-南通市图书馆

An Algorithm for Short-Circuit Current Interval in Distribution Networks with Inverter Type Distributed Generation Based on Affine Arithmetic

引用

Energy Engineering 2024年第7期121卷 1903-1920页

作者： Yan Zhang bowen du Benren Pan GuannanWang Guoqiang Xie Tong Jiang Electric Power Research Institute State Grid Jiangxi Electric Power Co.Ltd.Nanchang330096China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing102206China

during faults in a distribution network,the output power of a distributed generation(DG)may be ***,the output currents of distributed power sources are also affected by the output power,resulting in uncertainties in the calculation of the short-circuit current at the time of a ***,the impacts of such uncertainties around short-circuit currents will increase with the increase of distributed power ***,it is very important to develop a method for calculating the short-circuit current while considering the uncertainties in a distribution *** this study,an affine arithmetic algorithm for calculating short-circuit current intervals in distribution networks with distributed power sources while considering power fluctuations is *** proposed algorithm includes two *** the first stage,normal operations are considered to establish a conservative interval affine optimization model of injection currents in distributed power *** by the fluctuation range of distributed generation power at the moment of fault occurrence,the model can then be used to solve for the fluctuation range of injected current amplitudes in distributed power *** second stage is implemented after a malfunction *** this stage,an affine optimization model is first *** model is developed to characterizes the short-circuit current interval of a transmission line,and is constrained by the fluctuation range of the injected current amplitude of DG during normal ***,the range of the short-circuit current amplitudes of distribution network lines after a short-circuit fault occurs is *** algorithm proposed in this article obtains an interval range containing accurate results through interval *** with traditional point value calculation methods,interval calculation methods can provide more reliable analysis and calculation *** range of short-circuit current amplitude ob

关键词： Short circuit calculation inverter type distributed power supplies affine arithmetic distribution network

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于语义分割网络的植保机器人视觉伺服控制方法

引用

农业机械学报 2024年第5期55卷 21-27,39页

作者：李秀智方会敏朱玉垒杜博文董泓佑北京工业大学信息学部北京100124 江苏大学农业工程学院镇江212013 现代农业装备与技术教育部重点实验室(江苏大学) 镇江212013

为实现稳定可靠的植保机器人视觉伺服控制,提出了一种基于语义分割网络的作物行特征检测方法。基于语义分割网络ESNet实现农田场景图像像素级带状区域检测,并利用最小二乘算法拟合得到每条行作物线特征;在此基础上通过设计一种主导航线... 详细信息

为实现稳定可靠的植保机器人视觉伺服控制,提出了一种基于语义分割网络的作物行特征检测方法。基于语义分割网络ESNet实现农田场景图像像素级带状区域检测,并利用最小二乘算法拟合得到每条行作物线特征;在此基础上通过设计一种主导航线提取算法获取导航路径,并利用卡尔曼滤波对主导航线几何参数进行平滑处理,有效抑制了不平整地面导致的机器人运动颠簸与视觉图像测量噪声引起的导航参数波动。继而构建机器人前轮转向、后轮差速的阿克曼运动学模型;在图像空间坐标下设计纯追踪控制器实现植保机器人的伺服运动控制。大田环境下的现场实验结果为:总体横向偏差为0.092 m,验证了本文方法的有效性。

关键词：植保机器人视觉伺服控制深度学习语义分割网络作物行特征检测

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Conception and Exploration of Using Data as a Service in Tunnel Construction with the NATM

引用

Engineering 2018年第1期4卷 123-130页

作者： bowen du Yanliang du Fei Xu Peng He State Key Laboratory of Software Development Environment Beihang University Beijing 100083 China Structural Health Monitoring and Control Institute Shijiazhuang Tiedao University Shijiazhuang 050043 China Research Center of Geotechnical and Structural Engineering Shandong University Jinan 250061 China

The New Austrian Tunneling Method （NATM） has been widely used in the construction of mountain tun- nels, urban metro lines, underground storage tanks, underground power houses, mining roadways, and so on, The variation patterns of advance geological prediction data, stress-strain data of supporting struc- tures, and deformation data of the surrounding rock are vitally important in assessing the rationality and reliability of construction schemes, and provide essential information to ensure the safety and scheduling of tunnel construction, However, as the quantity of these data increases significantly, the uncertainty and discreteness of the mass data make it extremely difficult to produce a reasonable con- struction scheme; they also reduce the forecast accuracy of accidents and dangerous situations, creating huge challenges in tunnel construction safety, In order to solve this problem, a novel data service system is proposed that uses data-association technology and the NATM, with the support of a big data environ- ment, This system can integrate data resources from distributed monitoring sensors during the construc- tion process, and then identify associations and build relations among data resources under the same construction conditions, These data associations and relations are then stored in a data pool, With the development and supplementation of the data pool, similar relations can then he used under similar con- ditions, in order to provide data references for construction schematic designs and resource allocation, The proposed data service system also provides valuable guidance for the construction of similar projects.

关键词： New Austrian Tunneling Method Big data environments Data as a service Tunnel construction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Travel Patterns Analysis of Urban Residents Using Automated Fare Collection System

引用

Chinese Journal of Electronics 2016年第1期25卷 40-47页

作者： WANG Ya du bowen RONG Qiannan LIN Xia State Key Laboratory of Software Development Environment Beihang University School of Software Beihang University

As one of the essential information, passenger Origin-destination(OD) matrix is crucial for transit system planning. Automated fare collection(AFC) system is widely used in big cities all around the world, OD data not only can be collected in dynamic way but also through citywide. It is only a byproduct of AFC and have the imperfection. This paper proposes a novel method to infer trip chain information of each commuter’s OD matrix based on travel pattern identify, and then the relationship between lines which have the character of the geographical proximity is used to calibrate the result of inferring. A serious of experiment results based on the real data show that the method has relatively high accuracy and can be use to practical application.

关键词： Smart card Public transportation Travel patterns

来源：

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

Real-time prediction of mechanical behaviors of underwater shield tunnel structure using machine learning method based on structural health monitoring data

引用

Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 886-895页

作者： Xuyan Tan Weizhong Chen Tao Zou Jianping Yang bowen du State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Software Development Environment Beihang UniversityBeijing100191China

Predicting the mechanical behaviors of structure and perceiving the anomalies in advance are essential to ensuring the safe operation of infrastructures in the long *** addition to the incomplete consideration of influencing factors,the prediction time scale of existing studies is ***,this study focuses on the development of a real-time prediction model by coupling the spatio-temporal correlation with external load through autoencoder network(ATENet)based on structural health monitoring(SHM)*** autoencoder mechanism is performed to acquire the high-level representation of raw monitoring data at different spatial positions,and the recurrent neural network is applied to understanding the temporal correlation from the time ***,the obtained temporal-spatial information is coupled with dynamic loads through a fully connected layer to predict structural performance in next 12 *** a case study,the proposed model is formulated on the SHM data collected from a representative underwater shield *** robustness study is carried out to verify the reliability and the prediction capability of the proposed ***,the ATENet model is compared with some typical models,and the results indicate that it has the best *** model is of great value to predict the realtime evolution trend of tunnel structure.

关键词： Shied tunnel Machine learning Monitoring Real-time prediction Data analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Continuous amino-functionalized University of Oslo 66 membranes as efficacious polysulfide barriers for lithium−sulfur batteries

引用

Frontiers of Chemical Science and Engineering 2023年第2期17卷 194-205页

作者： bowen du Yuhong Luo Feichao Wu Guihua Liu Jingde Li Wei Xue Hebei Provincial Key Laboratory of Green Chemical Technology and High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

The shuttle effect of soluble polysulfides is a serious problem impeding the development of lithium−sulfur ***,continuous amino-functionalized University of Oslo 66 membranes supported on carbon nanotube films are proposed as ion-permselective interlayers that overcome these issues and show outstanding suppression of the polysulfide shuttle *** proposed membrane material has appropriately sized pores,and can act as ionic sieves and serve as barriers to polysulfides transport while allowing the passage of lithium ions during electrochemical cycles,thereby validly preventing the shuttling of ***,a fast catalytic conversion of polysulfides is also achieved with the asdeveloped ***,lithium−sulfur batteries with this interlayer show a desirable initial capacity of 999.21 mAh·g^(-1)at 1 C and a durable cyclic stability with a decay rate of only 0.04%per cycle over 300 ***,a high area capacity of 4.82 mAh·cm^(-2)is also obtained even under increased sulfur loading(5.12 mg·cm^(-2))and a lean-electrolyte condition(E/S=4.8μL·mg^(-1)).

关键词： lithium−sulfur batteries aminofunctionalized University of Oslo 66 membrane polysulfide interlayer

来源：

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

Effects of a rooftop wind turbine on the dispersion of air pollutant behind a cube-shaped building

引用

Theoretical & Applied Mechanics Letters 2021年第5期11卷 296-303页

作者： Shuaibin Zhang Haoze Yang bowen du Mingwei Ge State Grid Pingdingshan Power Supply Company Pingdingshan 467001China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

The concentration distribution of urban air pollutants is closely related to people’s *** an important utilization form of urban wind power,rooftop wind turbines have been widely used in *** wake effect of the rooftop wind turbines will change the flow behind buildings and then affect the pollutant *** this end,the pollutant dispersion behind the building is studied via the computational fluid dynamics *** actuator disk model and idealized cube are adopted to model the wind turbine and the building,*** study shows that the rooftop wind turbine can reduce the pollutant mass fraction near the ground and the pedestrian *** to the wake effect of the rooftop wind turbine,the turbulent fluctuation behind the building is weakened,and the spanwise pollutant dispersion is ***,the rooftop wind turbine weakens the downwash movement of the building,which enhances the vertical pollutant dispersion.

关键词： Urban wind power Actuator disk model Wind-turbine wake Pollutant dispersion

来源：

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

无牙颌固定种植取模误吞事件1例及风险防范

引用

口腔医学研究 2024年第9期40卷 840-842页

作者：王爽段思意陈锐王子剑杜博文汤雨龙中国人民解放军北部战区总医院口腔科辽宁沈阳110000 中国医科大学辽宁沈阳110000 大连医科大学辽宁大连116000

本文报告1例无牙颌种植术后取模过程中误吞事件发生的详细经过,结合文献分析,总结意外误吞的预防和治疗措施,给临床医生以警示和参考,避免此类事故的发生。

关键词：无牙颌种植误吞异物胃肠镜

来源：

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

Pressure and flowrate distribution in central exhaust shaft with multiple randomly operating range hoods

引用

Building Simulation 2022年第1期15卷 149-165页

作者： Lingjie Zeng Leqi Tong Jun Gao bowen du Chengquan Zhang Lipeng Lv Changsheng Cao Xihui Ding College of Environmental Science and Engineering Tongji UniversityShanghai 200092China School of Mechanical Engineering Tongji UniversityShanghai 200092China Department of civil and mineral engineering University of TorontoTorontoCanada

Central flues are now commonly adopted in high-rise residential buildings in China for cooking oil fumes(COF)*** hoods of all floors are connected to the central shaft,where oil fumes were gathered and exhausted through the outlet at the building *** households may cook and use their range hood at random periods,there is great uncertainty of the amount of COF being *** addition,users can often adjust the exhaust rate of the range hood according to their *** a result,thousands of possible operating conditions consisting of distinct combinations of on/off conditions and fan speed occur randomly in the central COF exhaust system,causing the exhaust performance to vary considerably from condition to *** work developed a mathematical model for characterizing the operation of the central COF exhaust system in a high-rise residential building as well as its iterative solving ***-scale tests coupled with CFD simulation referring to a real 30-floor building were conducted to validate the proposed *** results show that the model agreed well with the CFD and experimental data under various system operating ***,the Monte-Carlo method was introduced to simulate the random operating characteristics of the system,and a hundred thousand cases corresponding to distinct system operating conditions were sampled and statistically analyzed.

关键词： central exhaust shaft building ventilation range hood high-rise residential building randomly operating Monte-Carlo simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Localization and characterization of intermittent pollutant source in buildings with ventilation systems:Development and validation of an inverse model

引用

Building Simulation 2021年第3期14卷 841-855页

作者： Lingjie Zeng Jun Gao Lipeng Lv bowen du Yalei Zhang Ruiyan Zhang Wei Ye Xu Zhang College of Environmental Science and Engineering Tongji UniversityShanghai200092China School of Mechanical Engineering Tongji UniversityShanghai 200092China Department of Civil and Mineral Engineering University of TorontoTorontoCanada

Terrorist attacks through building ventilation systems are becoming an increasing *** case pollutants are intentionally released in a building with mechanical ventilation systems,it is critical to localize the source and characterize its releasing *** inverse modeling studies have adopted the adjoint probability method to identify the source location and used the Tikhonov regularization method to determine the source releasing profile,but the selection of the prediction model and determination of the regularization parameter remain *** limitations can affect the identification accuracy and prolong the computational time *** address the difficulties in solving the inverse problems,this work proposed a Markov-chain-oriented inverse approach to identify the temporal release rate and location of a pollutant source in buildings with ventilation systems and validated it in an experimental *** the modified Markov chain,the source term was discrete by each time step,and the pollutant distribution was directly calculated with no *** forward Markov chain was reversed to characterize the intermittently releasing profile by introducing the Tikhonov regularization method,while the regularized parameter was determined by an automatic iterative discrepancy *** source location was further estimated by adopting the Bayes *** chamber experiments,the effectiveness of the proposed inverse model was validated,and the impact of the sensor performance,quantity and placement,as well as pollutant releasing curves on the identification accuracy of the source intensity was explicitly *** showed that the inverse model can identify the intermittent releasing rate efficiently and promptly,and the identification error for pollutant releasing curves with complex waveforms is about 20%.

关键词： intermittent source inverse identification Markov chain regularization parameter ventilation system

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：