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高铁网络发展下的站城空间与功能关系研究--以长三角地区为例

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中国名城 2024年第9期38卷 40-49页

作者：王磊张潇冉韦胜任宗悦中国科学院南京地理与湖泊研究所江苏省规划设计集团有限公司

在过去近20年里,中国高铁网络化已成为城市和区域空间发展的重要推动力,各级政府也在不同层面上实施了高铁站区建设与城市空间协同发展策略。为此,建立站城空间及站城功能联系的分析框架,以长三角为案例区,探讨不同类型高铁站的站区发... 详细信息

在过去近20年里,中国高铁网络化已成为城市和区域空间发展的重要推动力,各级政府也在不同层面上实施了高铁站区建设与城市空间协同发展策略。为此,建立站城空间及站城功能联系的分析框架,以长三角为案例区,探讨不同类型高铁站的站区发育及站城关系特征。结果表明,长三角地区高铁站城联系具有较大的分异特征,大多站区功能发育水平较低,区域中心城市和部分地级城市与其主要高铁站区之间相互强化发展,而其他高铁城市与站区之间功能联系有待提升,不同类型高铁站的站城功能联系发育水平受站区、城市和区域因素的交互影响。结合站区发展潜力、地区差异化的高铁出行需求、城市空间发展规划,建议提升站城交通服务质量、分类分级培育站区主导功能、优化站城功能联系。

关键词：高铁站城关系时空距离功能联系站区发展长三角地区

Usefulness of analyzing endoscopic features in identifying the colorectal serrated sessile lesions with and without dysplasia

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World Journal of Clinical Cases 2023年第29期11卷 6995-7003页

作者： Rui-gang wang Yu-Tang ren Xuan Jiang Lai wei Xiao-Fei Zhang Hao Liu Bo Jiang Department of Gastroenterology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Center for Hepatobiliary and Pancreatic Diseases Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Center for Clinical Epidemiology and Statistics Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Department of Pathology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

BACKGROUND Sessile serrated lesions(SSLs)are often missed on colonoscopy,and studies have shown this to be an essential cause of interstitial colorectal *** SSLs with dysplasia(SSL-D+),in particular,have a faster rate of carcinogenesis than conventional tubular ***,there is a clinical need for some endoscopic features with independent diagnostic value for SSL-D+s to assist endoscopists in making immediate diagnoses,thus improving the quality of endoscopic examination and *** To compare the characteristics of SSLs,including those with and without dysplasia(SSL-D+and SSL-D-),based on white light and image-enhanced endoscopy,to achieve an immediate differential diagnosis for *** From January 2017 to February 2023,cases of colorectal SSLs confirmed by colonoscopy and histopathology at the Gastrointestinal Endoscopy Center of Beijing Tsinghua Changgung Hospital were *** general,endoscopic,and histopathological data were reviewed and analyzed to determine the diagnostic *** analysis was used to find potential diagnostic factors,and then multivariate regression analysis was performed to derive endoscopic features with independent diagnostic values for the SSL-D+.RESULTS A total of 228 patients with 253 lesions were collected as a *** were 225 cases of colorectal SSL-D-s and 28 cases of SSL-D+*** to the colorectal SSL-D-,the SSL-D+was more common in the right colon(P=0.027)with complex patterns of depression,nodule,and elevation based on cloud-like surfaces(P=0.003),reddish(P3.684-94.974],microvascular varicose(OR=6.768,95%CI:1.717-26.677),and mixed pattern of crypt opening(OR=20.704,95%CI:2.955-145.086)as the independent predictors fo

关键词： Sessile serrated lesions Dysplasia Endoscopic features

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车辆与无人机协同配送路径规划问题研究进展

内燃机与配件 2024年第9期 129-131页

作者：付为刚廖喆中国民用航空飞行学院航空工程学院四川广汉618307

随着民用无人机技术的不断发展,无人机速度快、通行能力强等优势更加凸显。且无人机已经被一些企业应用到了物流配送当中。最近,一种车辆与无人机协同进行配送的模式在物流运输领域得到了广泛关注,国内外的学者针对车辆与无人机协同配... 详细信息

随着民用无人机技术的不断发展,无人机速度快、通行能力强等优势更加凸显。且无人机已经被一些企业应用到了物流配送当中。最近,一种车辆与无人机协同进行配送的模式在物流运输领域得到了广泛关注,国内外的学者针对车辆与无人机协同配送路径规划问题进行了大量的研究。首先,本文从优化目标以及约束两个方面对车辆与无人机协同配送路径规划模型进行了梳理。然后,对现有的车辆与无人机协同配送路径规划算法进行了分类总结。最后,探讨了车辆与无人机协同配送路径规划问题相关的研究热点与方向。

关键词：车辆与无人机协同路径规划物流配送

强风化花岗混合岩上硬下软地层公路隧道施工优化

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公路交通科技 2024年第7期41卷 153-162页

作者：袁刚徐金峰李守仁石州严绍明云南省交投集团投资有限公司云南昆明650228 同济大学土木工程学院上海200092 云南临云高速公路有限公司云南临沧675800

针对临云高速公路特长隧道全、强风化花岗混合岩上硬下软地层的特殊地质情况,采用原开挖支护方案施工过程中围岩变形收敛较大并可能发生局部坍塌、冒顶等问题,结合隧道变形监测结果,针对性提出缩短隧道台阶长度+锚杆长度及布置的优化方... 详细信息

针对临云高速公路特长隧道全、强风化花岗混合岩上硬下软地层的特殊地质情况,采用原开挖支护方案施工过程中围岩变形收敛较大并可能发生局部坍塌、冒顶等问题,结合隧道变形监测结果,针对性提出缩短隧道台阶长度+锚杆长度及布置的优化方案,并通过有限差分数值模拟软件对不同开挖支护工况的围岩压力、隧道变形、锚杆轴力和塑性区深度等进行对比分析。结果表明:隧道采用台阶法施工时,开挖至硬、软岩层交界处附近,由于拱脚下围岩性质软弱,无法形成可靠的支撑,上覆岩土体会挤压衬砌使其产生较大的沉降和收敛变形,且该交界位置的围岩压力最小;上硬下软地层隧道开挖过程中,中台阶开挖支护对隧道变形收敛影响最大,随着中台阶长度的缩短,隧道变形收敛逐渐减小,围岩压力逐渐增大;短锚杆对围岩的变形控制作用较弱,增长锚杆长度可以更好发挥锚杆的悬吊增强作用,充分利用了围岩的承载能力,减小了开挖支护后隧道的变形;采用上台阶、中台阶、下台阶、仰拱长度分别为4,6,2,2 m,锚杆长度分别为4.5,6.0,6.0,4.5 m的开挖支护方案既可以满足隧道变形收敛要求,也可以方便实际施工,保证了隧道的安全、快速掘进。

关键词：隧道工程施工优化数值模拟台阶长度锚杆布置上硬下软地层

可直接计算转向流量的改进型DIAL交通分配算法

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中国公路学报 2005年第4期18卷 83-86页

作者：任刚王炜东南大学交通规划与管理江苏省重点实验室江苏南京210096

为了在交通分配中直接计算转向流量而不是通过事后推算获取,利用转向—路段拓扑关系及其衍生路段上流量守恒的规律,对Logit交通分配中最常用的DIAL算法进行改进。改进后的DIAL算法既继承了原算法的基本结构和全部优点,又可在得到路段流... 详细信息

为了在交通分配中直接计算转向流量而不是通过事后推算获取,利用转向—路段拓扑关系及其衍生路段上流量守恒的规律,对Logit交通分配中最常用的DIAL算法进行改进。改进后的DIAL算法既继承了原算法的基本结构和全部优点,又可在得到路段流量的同时直接计算转向流量,且能避免传统的FURNESS、FRATOR等事后推算模型在进行路段流量至转向流量迭代推算时的过大计算量及其他缺点。最后通过一个经典算例验证了该算法的有效性。

关键词：交通工程转向流量改进的DIAL算法路段流量守恒交通分配

浙闽山地丘陵地区传统地域景观研究——以福建沙县为例

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中外建筑 2024年第3期 52-59页

作者：张嘉林任维福建农林大学风景园林与艺术学院

厘清人与自然和谐共生的传统人居智慧,是实现城乡人居环境高质量发展的必由之路。浙闽地区地域景观是传统人居智慧研究荟萃的重要区域之一,但既有研究对其内陆山地丘陵地区的关注与研究严重不足。选取闽中综合交通枢纽沙县为研究对象,... 详细信息

厘清人与自然和谐共生的传统人居智慧,是实现城乡人居环境高质量发展的必由之路。浙闽地区地域景观是传统人居智慧研究荟萃的重要区域之一,但既有研究对其内陆山地丘陵地区的关注与研究严重不足。选取闽中综合交通枢纽沙县为研究对象,从国土景观研究视角出发,运用景观层状体系研究方法,完成以下三方面研究:(1)梳理沙县传统人居环境发展史;(2)从山形地势、水系水利、农业生产与聚落营建4个方面进行区域景观系统的分层解析;(3)归纳总体格局、城邑景观2个尺度的沙县传统人居环境地域景观体系。研究有助于完善浙闽地区内陆山水人居环境地域景观及其传统人居智慧的普查性研究。

关键词：风景园林传统人居环境国土景观地域景观浙闽地区山地丘陵沙县

Experimental and numerical investigation of a Hall thruster with a chamfered channel wall

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Chinese Physics B 2018年第10期27卷 484-494页

作者： Hong Li Guo-Jun Xia wei Mao Jin-Wen Liu Yong-Jie Ding Da-ren Yu Xiao-gang wang Plasma Propulsion Laboratory Harbin Institute of Technology Harbin 150001 China Beijing Institute of Control Engineering Beijing 100190 China Department of Physics Harbin Institute of Technology Harbin 150001 China

A discharge channel with a chamfered wall not only has application in the design of modern Hall thrusters, but also exists where the channel wall is eroded, and so is a common status for these units. In this paper, the laws and mechanisms that govern the effect of the chamfered wall on the performance of a Hall thruster are investigated. By applying both experimental measurement and particle-in-cell simulation, it is determined that there is a moderate chamfer angle that can further improve the optimal performance obtained with a straight channel. This is because the chamfering of the wall near the channel exit can enhance ion acceleration and effectively reduce ion recombination on the wall, which is favorable to the promotion of the thrust and efficiency. However, the chamfer angle should not be too large; otherwise, both the density of the propellant gas and the distribution of the plasma potential in the channel are influenced, which is undesirable for efficient propellant utilization and beam concentration. Therefore, it is suggested that the chamfer shape of the channel wall is an important factor that must be carefully considered in the design of Hall thrusters.

关键词： Hall thruster chamfered wall discharge performance physical mechanism

Dispersal behaviors stimulated by habitat alterations in golden snub-nosed monkeys(Rhinopithecus roxellana)in the Qinling Mountains, China

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Zoological Research 2023年第2期44卷 366-369页

作者： Cheng-Liang wang Liang Chen gang He Xiao-Dong Yan Tong Wu wei Li Hai-Tao Zhao Yi ren wei-wei Fu Yan wang He Zhang Xiao-wei wang wei-Feng wang Hong-Tao Zhao Ru-Liang Pan Bao-Guo Li Shaanxi Key Laboratory of Animal Conservation Shaanxi Institute of ZoologyXi’anShaanxi 710032China Shaanxi Key Laboratory of Animal Conservation College of Life SciencesNorthwest UniversityXi’anShaanxi 710069China Shaanxi Nature Reserve and Wildlife Management Station Shaanxi Forestry BureauXi’anShaanxi 710082China school of Anatomy Physiology and Human BiologyUniversity of Western AustraliaWestern Australia 6907Australia International Centre of Biodiversity and Primate Conservation Dali UniversityDaliYunnan 671003China Shaanxi Niubeiliang National Nature Reserve Xi’anShaanxi 710100China Management Bureau of Shaanxi Changqing National Nature Reserve HanzhongZhejiang 723000China

DEAR EDITOR,Combining location data, species distribution modeling(Max Ent), and major conservation events, we analyzed historical distribution changes in golden snub-nosed monkeys(Rhinopithecus roxellana) in the Qinl... 详细信息

关键词： China Qinling Mountains

Vacuum-free fabrication of high-performance semitransparent perovskite solar cells via e-glue assisted lamination process

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Science China Chemistry 2019年第7期62卷 875-882页

作者： Hengkai Zhang Yaokang Zhang Guang Yang Zhiwei ren wei Yu Dong Shen Chun-Shing Lee Zijian Zheng gang Li The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057 China Department of Electronic and Information Engineering The Hong Kong Polytechnic University Hong Kong China Institute of Textiles and Clothing The Hong Kong Polytechnic University Hong Kong China Center of Super-Diamond and Advanced Films Department of Chemistry City University of Hong Kong Hong Kong China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalin 116023 China

From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsiloxane elastomer by an acid treatment and transfer *** with the D-sorbitol-doped PEDOT:PSS electric glue,we successfully demonstrated a vacuum-free and ambient lamination fabrication process for semi-transparent perovskite solar cells using triple cation Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)*** this manufacturing-friendly lamination process,we fabricated semitransparent perovskite solar cell devices with power conversion efficiencies up to 16.4%and variable transparencies.

关键词： perovskite solar cells lamination electric glue semi-transparent vacuum-free fabrication