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摩擦驱动焊接小车牵引力和通过性分析

焊接 2024年第4期 35-39页

作者：张建军黄继强薛龙李茂勇张瑞英北京石油化工学院北京102617

针对焊接小车对变曲率半径工件适应性差的问题,进行了理论研究,改进焊接小车的驱动系统,建立了焊接小车在斜坡工况下的力学模型,分析了焊接小车运动过程中的牵引力变化规律,为焊接小车设计提供了理论支持。在此基础上,研究了焊接小车在... 详细信息

针对焊接小车对变曲率半径工件适应性差的问题,进行了理论研究,改进焊接小车的驱动系统,建立了焊接小车在斜坡工况下的力学模型,分析了焊接小车运动过程中的牵引力变化规律,为焊接小车设计提供了理论支持。在此基础上,研究了焊接小车在外圆曲面和内圆曲面工况下的通过性,并计算出了2种特殊工况下特定结构和尺寸的焊接小车可以通过的最小曲率半径。基于上述分析结果设计出了一款基于摩擦传动的焊接小车,并进行了仿真验证,结果表明该焊接小车在变曲率半径轨道上具有良好的通过性,可以为焊接小车的设计提供技术保障。

关键词：焊接小车摩擦驱动通过性牵引力变曲率半径

Analysis and Calculation of Tourist Carbon Footprints——A Case Study of Hebei Yesanpo Scenic Area

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Chinese Journal of Urban and Environmental Studies 2014年第1期2卷 130-142页

作者： zhang ruiying Tianjin Agricultural University

The National Tourism Conference in 2010 strongly promoted the concept of energy conservation and emission reduction in the tourism *** then,low carbon travel has been the new direction in tourism *** concern has been put on energy conservation and emission reduction of tourism related elements,such as hotels,transportations,tourist attractions,and most importantly,the tourists *** quantitative assessment of tourist carbon footprint is the key *** research uses Yesanpo scenic area as the example and conducts the comparison and calculation of tourist carbon footprint from different places,attempts to organize different ideas on ways to analyze tourist carbon footprints,constructs a calculation and assessment model,analyzes and measures the levels of tourist carbon footprints from diverse modes of travel,origins,and purchasing *** research has developed a system for quantitative assessment of tourist carbon footprints,with the hope of strengthening the theories and methods on low-carbon travel.

关键词： Tourists carbon footprint Yesanpo

A Message Digest Disposing Algorithm Based on RC4

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Wuhan University Journal of Natural Sciences 2010年第3期15卷 251-254页

作者： LIUYabin CHEN Jing DU ruiying zhang Huanguo School of Computer Wuhan University Wuhan 430072 Hubei China

The characteristics of the wireless network determine the requirement of lightweight cryptography. Towards the huge cost of an existing algorithm such as MD5, this paper proposes a message digest scheme based on the RC4 algorithm which broadens the application area of the RC4 and decreases the requirement of resource or cost. To test the randomicity of the algorithm＇s di- gest, fifteen kinds of randomicity test to NIST randomicity test standard had been done, and the comparative analysis which compares the digest＇s randomicity of the algorithm with MD5 had been performed as well. The performance of the algorithm had been analyzed in aspects of mono-directivity, randomicity, practicality and complexness. Statistic tests and analysis results illustrated that our scheme was of low cost of computing, good statistic performance, high running speed and lightweight.

关键词： RC4 message digest algorithm cryptography information security

The Comparative Study on Peasant Sustainable Livelihood Models in Rural Tourism Areas——A Case from Jixian, Tianjin

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Chinese Journal of Urban and Environmental Studies 2015年第2期3卷 67-78页

作者： zhang ruiying XI Jianchao zhang Nan Tianjin Agricultural University Institute of Geographic Sciences and Natural Resources Research

The differences exist among rural areas of different tourism types in the aspects of peasant livelihood capital, livelihood strategy, and livelihood *** paper conducts the comparative studies on peasant sustainable livelihood on two representatives, Maojiayu village and Changzhou village in Jixian(a county in Tianjin), based on the fieldwork and participatory country evaluating *** study finds that:(1) in rural areas of different tourism types,where their natural background, history of development, resources endowment, and regional policy are different, their tourism livelihood capital is *** comparison finds huge differences in natural capital, material capital, and financial capital, but tiny difference in human resources capital and social capital for Maojiayu village and Changzhou village.(2) For the comparison of livelihood strategy and livelihood outcome, Maojiayu village mainly focus on the tourism-program-driven livelihood, while Changzhou village’s livelihood is driven by tourism facilities and natural *** transformation and upgrading of tourism accommodation can significantly promote the tourism livelihood outcome; meanwhile, the introducing of new tourism programs can also bring the same effect.(3) The peasants in Maojiayu village and Changzhou village feel more comfortable, confident, and healthier by realizing the integration and localization of living and employment, as well as solving the issues of Three Rural Issues, for example left-behind children and empty-nest elderly in rural *** the local government can help to further improve the livelihood capital and extent tourism industry chain in the rural tourism areas, the peasants will have more livelihood strategy choices to promote the rural tourism industry.

关键词： Jixian, Tianjin tourism village peasant livelihood comparison

Study on the Landscape Pattern of Dalian Jinshitan National Holiday Resort in the Context of Tourism Urbanization

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Chinese Journal of Urban and Environmental Studies 2017年第3期5卷 55-68页

作者： zhang ruiying XI Jianchao zhang Nan Tianjin Agricultural University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Resort-based urbanization is an important form of tourism *** paper analyzes the basic characteristics and diversity of landscape elements under the influence of the tourist development of Jinshitan National Holiday Resort(JNHR),discusses the changes in the spatial distribution of landscapes,and reveals how landscapes have changed under the influence of the tourism development of *** study shows that the whole landscape at Jinshitan has undergone a process from fragmentation to integration in the context of manmade tourism development and *** more tourism projects are developed,supporting infrastructures and facilities are continuously *** in Jinshitan have been vigorously developed in depth and extended from coastal area to inland *** shown by the changing spatial distribution of relocated and commercial housing estates since 1992,there have been differences in the location,living environment and available landscapes between the housing estates,indicating the heterogeneity of social space and inequality in the living environment.

关键词： Tourism urbanization Jinshitan landscape pattern evolution

The Research on Peasant Sustainable Livelihood Models in Rural Tourism Areas Under Urbanization——A Case from Jixian, Tianjin

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Chinese Journal of Urban and Environmental Studies 2015年第1期3卷 112-125页

作者： zhang ruiying XI Jianchao zhang Nan Tianjin Agricultural University Institute of Geographic Sciences and Natural Resources Research CAS

Livelihood is fundamental for rural families. A good livelihood model can help to increase the happiness of peasants and promote local harmonious development. During the process of urbanization, peasant livelihood is changing constantly. In rural tourism areas, tourism is a strong force for the development of urbanization, and the research of peasant livelihood is especially important. Based on the basic sustainable livelihood theoretical framework, this paper classifies the peasants in Jixian(a county in Tianjin) tourism areas into four types, including working household, tourism household, part-time tourism household, and part-time non-tourism household, to conduct a comprehensive analysis on livelihood capital, livelihood strategy and livelihood outcome by integrating the questionnaire, interview, observation statistical analysis, GIS and data analysis. We draw the following conclusions. First, during the development of rural tourism, there are hierarchy differences in the livelihood capital among different types of peasant households,and the disparity is increasing. The tourism household shows evidence of the best livelihood capital followed by the part-time tourism household, the part-time non-tourism household, and finally the employee household respectively. Second, the livelihood strategy of Jixian households shows a diversity which is dominated by tourism livelihood. However, because the tourism household and part-time tourism households show outstanding advantage in their livelihood strategy that will be constantly imitated by other peasants, which will lead to an increasing professionalization and specialization in rural tourism. Third, according to the comparative analysis, tourism household and part-time tourism household show a livelihood outcome which is wealthier, provides leisure, and of high-quality living standards. Therefore, the livelihood outcome can be improved obviously by following the professional tourism livelihood model through relying on

关键词： Jixian Tianjin rural tourism livelihood

基于增强现实声音仿真技术的母亲声音刺激对极早产儿的影响

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中国临床护理 2024年第5期16卷 265-268页

作者：余欣沙晓妍孙黎胡改青张瑞英梁茜贺芳广州医科大学附属妇女儿童医疗中心广州510000

目的探讨基于增强现实声音仿真技术的母亲声音刺激对极早产儿的影响。方法选取2021年1月-2022年6月在广州市某三级甲等医院出生的76例极早产儿为研究对象,采用随机数字表法将其分为对照组和观察组,各38例。对照组实施早产儿常规护理干预... 详细信息

目的探讨基于增强现实声音仿真技术的母亲声音刺激对极早产儿的影响。方法选取2021年1月-2022年6月在广州市某三级甲等医院出生的76例极早产儿为研究对象,采用随机数字表法将其分为对照组和观察组,各38例。对照组实施早产儿常规护理干预,观察组在对照组基础上采取基于增强现实声音仿真技术的母亲声音刺激干预,连续干预14 d。比较2组生长发育指标、心率、康复指标、并发症发生率。结果2组心率在时间、组间、交互效应上比较,差异均有统计学意义(F_(时间)=10.318,P0.05)。结论基于增强现实声音仿真技术的母亲声音刺激对极早产儿干预效果良好,可稳定早产儿的心率,促进患儿尽早达到全肠道喂养。

关键词：增强现实声音仿真技术母亲声音刺激极早产儿生长发育心率

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华北克拉通南部早前寒武纪基底形成与演化

岩石学报 2017年第10期33卷 3027-3041页

作者：张瑞英孙勇大陆动力学国家重点实验室西北大学地质学系西安710069 山西师范大学地理科学学院临汾041004

简要总结了华北克拉通南部鲁山地区、小秦岭地区、登封及中条山地区的早前寒武纪地质事件序列及其地质意义,并对各地区地质特征和变质演化特点进行对比。结合前人研究工作,初步探讨了华北克拉通南部早前寒武纪基底的演化特点、陆壳形成... 详细信息

简要总结了华北克拉通南部鲁山地区、小秦岭地区、登封及中条山地区的早前寒武纪地质事件序列及其地质意义,并对各地区地质特征和变质演化特点进行对比。结合前人研究工作,初步探讨了华北克拉通南部早前寒武纪基底的演化特点、陆壳形成的主要时期和华北南部基底的构造区划等问题,提出几点认识:1)华北克拉通南部鲁山、中条山、小秦岭等地区均有2.7~2.9Ga岩石记录,以英云闪长质-奥长花岗质-花岗闪长质(TTG)岩石为主,它们共同构成华北南缘的古老结晶基底,并经历了新太古代晚期~2.5Ga构造-热事件,标志着华北克拉通南部在新太古代末期可能已经形成统一基底;2)华北克拉通南部主要的陆壳形成时期为中太古代晚期-新太古代,与全球其他主要克拉通一致,而古元古代早-中期则以地壳再循环为主;3)综合地质、地球化学等特点,将华北南部鲁山-小秦岭地区和中条山等地区划归为"南部古陆块",并提出该陆块呈现为一个大型的倾伏向斜构造,可能在新太古代晚期已经形成,其枢纽向南东倾斜。"南部古陆块"在新太古代末期与其它微陆块拼合,并发生了变质作用和陆壳的活化与再循环,共同指示新太古代晚期华北克拉通统一基底的形成。

关键词：早前寒武纪基底形成与演化华北克拉通南部

Integrative taxonomy of the Plain-backed Thrush(Zoothera mollissima)complex(Aves,Turdidae)reveals cryptic species,including a new species

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Chinese Birds 2016年第1期7卷 2-39,1页

作者： Per Alstrom Pamela C.Rasmussen Chao Zhao Jingzi Xu Shashank Dalvi Tianlong Cai Yuyan Guan ruiying zhang Mikhail V.Kalyakin Fumin Lei Urban Olsson Department of Animal Ecology Evolutionary Biology CentreUppsala University Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of Sciences Swedish Species Information Centre Swedish University of Agricultural Sciences Department of Integrative Biology and MSU Museum Michigan State University Bird Group The Natural History Museum at Tring Cloud Mountain Conservation Department of Evolutionary Biology Evolutionary Biology CentreUppsala University Researchers for Wildlife Conservation F-21National Centre for Biological Sciences College of Life Sciences University of Chinese Academy of Sciences Zoological Museum of Lomonosov Moscow State University Systematics and Biodiversity Department of Biology and Environmental SciencesUniversity of Gothenburg

Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly ***: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic(two mitochondrial and two nuclear markers), ecological and distributional ***: In earlier field observations, we noted two very different song types of "Plain-backed" Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China("Alpine Thrush"); a forest breeder in the eastern Himalayas and northwest Yunnan(at least), China("Himalayan Forest Thrush"); and a forest breeder in central Sichuan("Sichuan Forest Thrush"). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is probably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists("Yunnan Thrush"). However, we find no consistent morphological differences from Alpine Thrush, and its breeding range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative "Yunnan Thrush" as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato(s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocincla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto(s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest ***: The

关键词： Systematics Morphology Bioacoustics Altitudinal distributions Genetic distances Undescribed taxa Zoothera dixoni Lectotypification Holotype