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Measuring positive public transit accessibility using big transit data

Geo-Spatial Information Science 2021年第4期24卷 722-741页

作者： Tong Zhang Wenyuan Zhang zhenxuan he State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Department of Computer Science and Engineering New York UniversityNew YorkNYUSA

Most of the current existing accessibility measures quantify the potential of reaching desirable opportunities across space and ***,these potential measurements only illus-trate the maximum possible accessibility a person can have,which may not accurately measure real-world transit accessibility in urban *** paper introduces a novel methodology to measure positive public transit accessibility based on multi-source big public transit data such as Smart Card Data(SCD)and Global Navigation Satellite System trajectory data,which embed rich travel information and real-world spatio-temporal ***,we use multi-source transit data to reconstruct trip chains,which are used to extract popular destinations.A novel transit accessibility measure is defined to account for latent trip information such as mode/route preference,opportunity attraction,and travel impedance that are difficult to capture explicitly via traditional normative ***,we produce accessibility maps to visualize time-varying and heterogeneous accessibility patterns distributed over the study *** performed an empirical evaluation on real-world transit data collected in Shenzhen City,China,demonstrating the applicability and effectiveness of the proposed method in mapping positive transit accessibility over large metropolitan *** results and findings of the empirical study demonstrate that the proposed positive accessibility measure can better capture travel behavior characteristics and constraints than traditional normative *** measure-ment method can be used as a practical high-resolution mapping tool for transit decision makers in evaluating public transit systems,supporting strategic transit planning,and improv-ing daily transit management.

关键词： Public transit positive accessibility smart card data spatio-temporal

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差分度量的三维模型语义部件定义方法

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小型微型计算机系统 2024年第12期45卷 3050-3056页

作者：谭小慧朱晓贺振轩杨洪鼎李俊首都师范大学人工智能教育研究院北京100048 首都师范大学信息工程学院北京100048 埃克塞特大学计算机科学学院埃克塞特EX44QJ

本文提出了一种基于差分度量的三维模型语义部件描述符计算方法.当三维模型发生缺失变化时,模型上点的全局描述符产生相应的变化,利用这两者变化的映射关系,使用随机森林算法进行描述符变化量到对应部件的标签映射,可实现对部件的语义... 详细信息

本文提出了一种基于差分度量的三维模型语义部件描述符计算方法.当三维模型发生缺失变化时,模型上点的全局描述符产生相应的变化,利用这两者变化的映射关系,使用随机森林算法进行描述符变化量到对应部件的标签映射,可实现对部件的语义特征提取.对于一族模型的标签化问题,本文利用提出的部件描述符计算方法,将模型中对称的部件统一化标签,解决了模型部件的对称部件快速标签化问题.使用半监督的方法,解决了族内模型的差异性问题.在公开COSEG数据集上进行模型部件自动语义标签化,实验结果证明了所提方法的有效性.

关键词：三维模型模型分割描述符

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棒材用小离心高速钢轧辊的一种浇铸方法

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河北冶金 2015年第9期 63-64页

作者：郭小军贺振轩李晓刚中钢集团邢台机械轧辊有限公司河北邢台054025

分析了棒材精轧机架用辊现状,介绍了高速钢轧辊常用的生产方法及传统复合离心工艺存在的问题。采用芯部溢流浇铸方式,实现了对高速钢离心复合轧辊结合层质量的控制,同时得到高的辊颈强度,成功生产出了抗事故性好,能够适用于棒材轧机精... 详细信息

分析了棒材精轧机架用辊现状,介绍了高速钢轧辊常用的生产方法及传统复合离心工艺存在的问题。采用芯部溢流浇铸方式,实现了对高速钢离心复合轧辊结合层质量的控制,同时得到高的辊颈强度,成功生产出了抗事故性好,能够适用于棒材轧机精轧机架的小离心高速钢轧辊。

关键词：棒材精轧机架高速钢轧辊离心复合浇铸参数溢流法

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Monolithic integration of flexible lithium-ion battery on a plastic substrate by printing methods

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Nano Research 2019年第10期12卷 2477-2484页

作者： zhenxuan Zhao Huaqiang Wu Institute of Microelectronics Tsinghua UniversityBeijing 100084China

En ergy storage devices with flexible form factor have become critical components of wearable electr onic *** spired by methods of monolithic integration in the microelectronics fabrication process,we propose a planar flexible full-solid-state lithium-ion battery(FSLB)architecture and a layer-by-layer stencil printing assembly method for fabricating batteries on polyethylene terephthalate(PET)*** use quasi-solid electrolyte based on LiTFSI and ultraviolet(UV)-curable ethoxylated trimethylolpropane triacrylate(ETPTA)polymeric matrix in combination with Li4Ti50i2(LTO)/LiFePO4(LFP)-based *** mechanical flexibility(hemical characteristics of electrolyte,including ion conductivity,physical stability during room-temperature and tender assembly processes,are promising.A complete thin film-shape FSLB demonstrated working operation both under planar and bending *** unique architecture and assembly processes open new ways for planar flexible devices to be integrated with flexible energy devices.

关键词： flexible printable full-solid-state battery lithium-ion battery polymer electrolyte

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一种基于YOLO的口罩佩戴检测终端的设计

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现代计算机 2023年第11期29卷 117-120页

作者：张良陈周欢林耿名叶绮雯何镇轩韶关学院信息工程学院韶关512005

对新冠疫情现状的调查,依托RT-thread平台设计一款用于公共场所进出口对口罩佩戴的检测和提醒(未佩戴口罩时)终端。通过植入推理模型,使终端在脱机状态下正常工作。硬件平台由主板ART-PI以及多媒体拓展板和GC0328摄像头模块构成。选用YO... 详细信息

对新冠疫情现状的调查,依托RT-thread平台设计一款用于公共场所进出口对口罩佩戴的检测和提醒(未佩戴口罩时)终端。通过植入推理模型,使终端在脱机状态下正常工作。硬件平台由主板ART-PI以及多媒体拓展板和GC0328摄像头模块构成。选用YOLOv5s和YOLO-Fastest网络模型分别应用于联机状态和脱机状态。经过训练的YOLO目标检测模型,对同一组100张图片测试,在联机状态下准确率达到了92.3%,在脱机状态下达到了74.9%。

关键词： RT-Thread YOLO目标检测口罩识别

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Cultivation and Dissemination of Core Values in the New Media Age

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学术界 2018年第6期 257-271页

作者： Xu zhenxuan Anhui Broadcasting Movie and Television College Hefei Anhui 230011

The rapid development of information technology and the fierce conflict of multiple values lead information communication to present different characteristics in the new media era,which has brought both challenges and opportunities to the cultivation and dissemination of core *** the development of new media,the environment for cultivating core values is becoming increasingly complex,and the main content of core values is being dispelled,thus weakening its function of leading and affecting its guiding *** the same time,the development of new media can not only broaden the cultivation mode of core values and highlight the powerful force of core values,but also stimulate the people to highly identify with core *** present,the new media has become the main tool and mainstream position for the dissemination of core values,so it is necessary to continuously innovate the communication mechanism of the core values,and enhance their pertinence and effectiveness communication,so that they can play a leading role in the whole society better.

关键词：媒介传播耕作价值年龄信息通讯开发

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Optimal guidance of extended trajectory shaping

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Chinese Journal of Aeronautics 2014年第5期27卷 1259-1272页

作者： Wang Hui Lin Defu Cheng zhenxuan Wang Jiang School of Aerospace and Engineering Beijing Institute of Technology China North Industries Group Corporation

To control missile＇s miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control *** extended trajectory shaping guidance（ETSG） law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile＇s acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed.

关键词： Extended trajectory shaping Impact angle error Miss distance Missile Optimal guidance Terminal constraint

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The mapping methods and division of tectonic units of the regional tectonic map in the eastern China seas and adjacent regions

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Acta Oceanologica Sinica 2009年第4期28卷 57-64页

作者： YIN Yanhong ZHANG Xunhua WEN Zhenhe GUO zhenxuan Qingdao Institute of Marine Geology Qingdao 266071 China

The geological-geophysical map series of the eastern China seas and adjacent region （1：1 000 000） will be published in the late half year of 2009. The regional tectonic map is one of the main professional maps. The Mapping methods, the division method of geological tectonic units and the main geological tectonic units are mainly discussed. The strata from Pliocene to Holocene are peeled off so as to display the Pre-Pliocene structures. In basins, isopaches are drawn for the Cenozoic deposits. The plate tectonic theory and present tectonic pattern are adopted as the priorities in tectonic division. As to the division of intraplate tectonic units, it is a revision, complement and improvement of previous dividing systems, and the nomenclature for each tectonic unit follows the current system in China. The first-order tectonic unit is plate （Pacific Plate, Eurasian Plate and Philippine Sea Plate）. The second-order tectonic unit is tectonic domain （East Asian continental tectonic domain,East Asian continental margin tectonic domain and west Pacific tectonic domain）. The Philippine Sea Plate and the west part of the Pacific Plate are called the West Pacific tectonic domain. The part of the Eurasian Plate involved in this study area can be further divided into East Asian continental tectonic domain and East Asian continental margin tectonic domain. The East Asian continental margin domain is composed of the Ryukyu island arc, the Okinawa Trough back-arc basin and the back-arc basin of Sea of Japan. The East Asian continental tectonic domain in this study area is composed of the Sino-Korea Massif, the Changjiang River （Yangtze） Massif and South China Massif. In turn, these massifs consist of basins, folded belts or uplift zones. The basins,the folded belts or the uplift zones are further divided into uplifts and depressions made up of sags and swells.

关键词： regional tectonic map eastern China seas geological tectonic units division

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Symmetric and symplectic methods for gyrocenter dynamics in time-independent magnetic fields

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第2期7卷 139-151页

作者： Beibei Zhu zhenxuan Hu Yifa Tang Ruili Zhang LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190P.R.China School of Software Fudan University Shanghai 201203P.R.China Department of Modern Physics and School of Nuclear Science and Technology University of Science and Technology of China hefei 230026 P.R.China

We apply a second-order symmetric Runge–Kutta method and a second-order symplectic Runge–Kutta method directly to the gyrocenter dynamics which can be expressed as a noncanonical Hamiltonian *** numerical simulation results show the overwhelming superiorities of the two methods over a higher order nonsymmetric nonsymplectic Runge–Kutta method in long-term numerical accuracy and near energy ***,they are much faster than the midpoint rule applied to the canonicalized system to reach given precision.

关键词： Symmetric Runge-Kutta method symplectic Runge-Kutta method numerical accuracy near energy conservation

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Hydrogen release of NaBH_(4) below 60 ℃ with binary eutectic mixture of xylitol and erythritol additive

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Chinese Journal of Chemical Engineering 2024年第7期71卷 225-234页

作者： Yugang Shu Jiaguang Zheng Chengguo Yan Ao Xia Meiling Lv zhenxuan Ma Zhendong Yao School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China

NaBH_(4) was widely regarded as a low-cost hydrogen storage material due to its high-mass hydrogen capacity of approximately 10.8%(mass)and high volumetric hydrogen capacity of around 115 g·L^(–1).However,it exhibits strong stability and requires temperatures above 500℃ for hydrogen release in practical *** this study,two polyhydric alcohols,xylitol and erythritol(XE),were prepared as a binary eutectic sugar alcohol through a grinding-melting *** binary eutectic sugar alcohol was used as a proton-hydrogen carrier to destabilize NaBH_(4).The 19NaBH_(4)-16XE composite material prepared by ball milling could start releasing hydrogen at 57.5℃,and the total hydrogen release can reach over 88.8%(4.45%(mass))of the theoretical *** the 19NaBH_(4)-16XE composite was pressed into solid blocks,the volumetric hydrogen capacity of the block-shaped composite could reach 67.2 g·L^(–1).By controlling the temperature,the hydrogen desorption capacity of the NaBH_(4)-XE composite material was controllable,which has great potential for achieving solid-state hydrogen production from NaBH_(4).

关键词： Hydrogen Desorption Binary mixture NaBH_(4) Xylitol Erythritol

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