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A cross-analysis framework formulti-source volunteered, crowdsourced, and authoritative geographic information: The case study of volunteered personal traces analysis against transport network data

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Geo-Spatial Information Science 2018年第3期21卷 257-271页

作者： Gloria Bordogna Steven Capelli Daniele e.Ciriello Giuseppe Psaila CNR IReA MilanoItaly DISCo Universitádegli studi di Milano BicoccaSesto San GiovanniItaly DIGIP University of BergamoDalmineItaly

The paper discusses the need of a high-level query language to allow analysts,geographers and,in general,non-programmers to easily cross-analyze multi-source vGI created by means of apps,crowd-sourced data from social networks and authoritative geo-referenced data,usually represented as JSON data sets(nowadays,the de facto standard for data exported by social networks).Since an easy to use high-level language for querying and manipulating collections of possibly geo-tagged JSON objects is still unavailable,we propose a truly declarative language,named J-CO-QL,that is based on a well-defined execution model.A plug-in for a GIS permits to visualize geo-tagged data sets stored in a NoSQL database such as MongoDB;furthermore,the same plug-in can be used to write and execute J-CO-QL queries on those *** paper introduces the language by exemplifying its operators within a real study case,the aim of which is to understand the mobility of people in the neighborhood of Bergamo ***-analysis of data about transportation networks and vGI from travelers is performed,by means of J-CO-QL language,capable to manipulate and transform,combine and join possibly geo-tagged JSON objects,in order to produce new possibly geo-tagged JSON objects satisfying users’needs.

关键词： Cross-analysis framework comparing vGI crowd-sourced and authoritative geographical data JSON data-sets declarative query language heterogeneous data-sets

Rock engineering design of post-tensioned anchors for dams-A review

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岩石力学与工程学报 2015年第1期34卷 1-13页

作者： e.T.Brown Golder Associates Pty Ltd.

High-capacity, post-tensioned anchors have found wide-spread use, originally in initial dam design and construction, and more recently in the strengthening and rehabilitation of concrete dams to meet modern design and safety standards. Despite the advances that have been made in rock mechanics and rock engineering during the last 80 years in which post-tensioned anchors have been used in dam engineering, some aspects of the rock engineering design of high-capacity rock anchors for dams have changed relatively little over the last 30 or 40 years. This applies, in particular, to the calculations usually carried out to establish the grouted embedment lengths required for deep, post-tensioned *** calculations usually make simpli fi ed assumptions about the distribution and values of rock e grout interface shear strengths, the shape of the volume of rock likely to be involved in uplift failure under the in fl uence of a system of post-tensioned anchors, and the mechanism of that failure. The resulting designs are generally conservative. It is concluded that these aspects of the rock engineering design of large, posttensioned rock anchors for dams can be significantly improved by making greater use of modern,comprehensive, numerical analyses in conjunction with three-dimensional(3D) models of the rock mass structure, realistic rock and rock mass properties, and the results of prototype anchor tests in the rock mass concerned.

关键词： Dam engineering Post-tensioned anchors Rock engineering design Groutetendon bond Rockegrout bond Rock mass uplift failure

基于自适应Sketch的高速网络流大小测量机制

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中国科学：信息科学 2024年第7期54卷 1677-1691页

作者：卜霄菲黄河孙玉娥王兆杰吴晓灿沈阳师范大学软件学院沈阳110034 苏州大学计算机科学与技术学院苏州215006 苏州大学轨道交通学院苏州215131

高速网络流大小的测量面临着高速存储资源极度稀缺的挑战,难以满足海量流式数据的实时存储需求.目前的研究大多采用存储资源共享技术,以便将设计的估计器置于稀缺的高速片上缓存中.然而,这种方法引入了大量难以消除的噪声,导致中小规模... 详细信息

高速网络流大小的测量面临着高速存储资源极度稀缺的挑战,难以满足海量流式数据的实时存储需求.目前的研究大多采用存储资源共享技术,以便将设计的估计器置于稀缺的高速片上缓存中.然而,这种方法引入了大量难以消除的噪声,导致中小规模流的估算精度不高.为了解决这一问题,本文提出一种能根据流大小自适应调整所占用存储空间的自适应Sketch技术,并在此基础上设计出一个高精度、低存储开销的每流大小估计器.自适应Sketch技术利用可逆计数器高效滤除海量噪声小流,并进一步采用采样概率逐层递减的采样计数器实现对不同规模流的自适应采样计数,从而控制大流对资源的过多占用,实现了低开销、高精度的每流大小测量.基于真实网络数据集CAIDA 2019的仿真实验表明,所提出的自适应Sketch流大小估计器的平均相对误差较现有机制降低了接近1个数量级.

关键词：高速网络流大小测量 Sketch 噪声小流过滤可逆计数器

effects of Grain Refinement by eCAP on the Deformation Resistance of Al Interpreted in Terms of Boundary-Mediated Processes

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Journal of Materials Science & Technology 2016年第12期32卷 1309-1320页

作者： W.Blum J.Dvorak P.Kral P.eisenlohr v.Sklenicka Department of Materials Science and engineering Institute I: General Materials Properties Friedrich-Alexander University Erlangen-Niirnberg Martensstn 5 Erlangen 91058 Germany Institute of Physics of Materials Academy of Sciences of the Czech Republic Zizkova 22 Brno CZ 61662 Czech Republic Department of Chemical engineering and Materials Science Michigan State University East Lansing M148824 USA

Results of a large set of tensile and compressive creep tests on pure Al were reanalyzed for the influence of low-and high-angle grain boundaries on the deformation resistance at the temperature T = 473 K = 0.51 Tmwhere Tm is the melting *** treatment by equal channel angular pressing followed by heating to T led to strong increase of areal fraction of high-angle boundaries in a structure of subgrains of ≈10^-6m in size,accompanied by significant reduction of subgrain strengthening and of the stress sensitivity of the deformation rate.（Sub）grain strengthening by low-angle boundaries is most effective;the strengthening effect virtually disappears during creep as the boundary spacings coarsen toward their stress-dependent,quasi-stationary size *** same type of coarsening is found for（sub）grain structures with large fraction of high-angle boundaries;in the quasi-stationary state they lead to softening at low and strengthening at high stresses,and a significant increase in tensile fracture strain to values up to *** results are analogous to former results for Cu and are explained in the same way by the influence of boundaries on storage and recovery of crystal defects and the homogenization of glide.

关键词： Deformation Grain boundaries equal channel angular pressing (eCAP) Creep Dynamic recovery Fine grained microstructure

An implementation assessment of China's environmental Information Disclosure Decree

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Journal of environmental Sciences 2010年第10期22卷 1649-1656页

作者： Lei Zhang Arthur e J Mol Guizhen He Yonglong Lu School of environment and Natural Resources Renmin University of China Beijing 100872 China environmental Policy Group Wageningen University Hollandseweg 1 6706 KN Wageningen The Netherlands State Key Laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

China＇s 2007 Open Government Information Regulations is widely considered as a milestone in the country＇s information policy history and is praised as a ＂sunshine program＂. The environmental Information Disclosure Decree was the first to operationalize these general regulations into a sectorai information disclosure system on environment. This study assessed the implementation of the environmental information disclosure system about six months after the Decree took effect on May 1, 2008. Through reviewing the websites of all 31 provincial environmental Protection Bureaus and the Ministry of environmental Protection, conducting an experiment with actual information disclosure request, and through interviews with all provincial environmental Protection Bureaus, this article concluded that the implementation of the environmental information disclosure system still fails short. Future improvements should focus on further publicity of the regulations and decree to enhance public participation, the establishment of an independent evaluation and supervision system for information disclosure, the exchange of experiences and best practices among provincial environmental Protection Bureaus, and on strengthening the legal status of environmental information disclosure.

关键词： environmental information disclosure environmental governance

Making Biological Materials

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Journal of Bionic engineering 2005年第4期2卷 209-237页

作者： Julian F.v.vincent Centre for Biomimetics and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

1 Chemistry and synthesis 1.1 Production and control of materials These days there can be few people who do not know that proteins are defined by DNA. DNA is made of two strands, each of which has along it, like a string of fairy lights, side branches that meet between the strands and hold them together. It is the sequence of these paired side branches （bases） that stores the information needed to define a protein. Three of the bases in sequence provide the information which, translated by the cell＇ s machinery, codes for a particular amino acid. Amino acids polymerise to make up specific proteins and, eventually, us. In defining an organism, that can weigh several tons, in its sequence of bases, the minute amount of DNA necessary for this task is an amazing example of data compression. When I was at school in Cambridge, shortly after Crick and Watson had worked out the basic structure of DNA for their Nobel prize, an enterprising breakfast cereal company had a cardboard cut-out DNA double spiral on the back of their packets. No doubt if you ate enough breakfasts you could save up for a whole gene. I don＇ t know what bit of protein the DNA coded for - I suspect no one did at the time. I remember another of the big names in genetics, Sydney Brenner （whose son went to our school and who later also got a Nobel prize）,

关键词： Making Biological Materials

Rotational Swashplate Pulse Continuously variable Transmission Based on Helical Gear Axial Meshing Transmission

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Chinese Journal of Mechanical engineering 2012年第6期25卷 1138-1143页

作者： SUN Jiandong FU Wenyu LeI Hong TIAN e LIU Ziping College of Mechanical and electrical engineering Beijing Union UniversityBeijing 100020China

The current research on pulse continuously variable transmission（CvT） is mainly focused on reducing the pulse degree and making pulse degrees a constant value. Current research mainly confined to find out new design parameters by using the method of optimization, and reduce the pulse degree of pulse CvT and its range of variation. But the fact is that the reduction of the pulse degree is not significant. This article presents a new structure of mechanical pulse CvT--the rotational swashplate pulse CvT with driven by helical gear axial meshing. This transmission is simple and compact in structure and low in pulsatile rate （it adopts 6 guide rods）, and the pulsatile degree is irrelevant to the transmission ratio. Theoretically, pulsatile rate could be reduced to zero if appropriate curved surface of the swashplate is used. Compared with the connecting rod pulse CvT, the present struc^tre uses helical gear mechanism as transmission part and it avoids unbalanced inertial force in the former model. This paper analyzes the principle of driving of this transmission, presents its mechanical structure, and discusses its motion characteristics. experimental prototype of this type of CvT has been manufactured. Tests for the transmission efficiency（when the rotational speed of the output shaft is the maximum） and the angular velocity of the output shaft have been carried out, and data have been analyzed. The experimental results show that the speed of the output shaft for the experimental prototype is slightly lower than the theoretical value, and the transmission efficiency of the experimental prototype is about 70%. The pulse degree of the CvT discussed in this paper is less than the existing pulse CvT of other types, and it is irrelevant to the transmission ratio of the CvT. The research provides the new idea to the CvT study.

关键词： pulse continuously variable transmission pulsatile rate motion analysis

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拉力式甘蔗剥叶机剥叶元件作业参数研究

中国农机化学报 2024年第7期45卷 122-126页

作者：陈明东陆静平林运东冯武铠钟义略广西大学机械工程学院南宁市530004

拉力式甘蔗剥叶机剥叶元件合理的作业参数可有效改善剥叶机构剥叶质量,为降低含杂率,建立甘蔗剥叶过程仿真模型,采用单因素仿真试验分析剥叶辊筒转速、剥叶角度及剥叶辊筒中心距(剥叶元件交错深度)对蔗叶所受峰值应力的影响规律和蔗叶... 详细信息

拉力式甘蔗剥叶机剥叶元件合理的作业参数可有效改善剥叶机构剥叶质量,为降低含杂率,建立甘蔗剥叶过程仿真模型,采用单因素仿真试验分析剥叶辊筒转速、剥叶角度及剥叶辊筒中心距(剥叶元件交错深度)对蔗叶所受峰值应力的影响规律和蔗叶的剥离断裂情况,确定参数范围;在仿真分析基础上采用中心组合法进行多因素样机试验,探究3个作业参数对含杂率的影响规律并得出最佳作业参数:剥叶角度120°、剥叶辊筒中心距77.2 mm、剥叶辊筒转速128 r/min、最小含杂率为2.03%,样机试验验证所得含杂率结果为2.09%。为改善拉力式甘蔗剥叶机剥叶效果、提高作业适应性提供参考。

关键词：甘蔗拉力式剥叶元件剥叶效果

86.2%氧化亚铜可湿性粉剂与化学农药混配对百合叶斑病的防治效果评价

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中国生物防治学报 2024年第5期40卷 1149-1159页

作者：李梦梁巧兰魏列新蔺珂陈应娥芮静耿洪旗甘肃农业大学植物保护学院/甘肃省农作物病虫害生物防治工程实验室兰州730070

为探究矿物源农药氧化亚铜WP与化学农药混配对百合叶斑病Alternaria alternata的防治效果。采用喷雾法、离体叶片法分别测定了矿物源农药86.2%氧化亚铜WP与3种化学农药混配后混配剂的增效效果及持效期。结果表明,86.2%氧化亚铜WP:70%霉... 详细信息

为探究矿物源农药氧化亚铜WP与化学农药混配对百合叶斑病Alternaria alternata的防治效果。采用喷雾法、离体叶片法分别测定了矿物源农药86.2%氧化亚铜WP与3种化学农药混配后混配剂的增效效果及持效期。结果表明,86.2%氧化亚铜WP:70%霉灵SP(7:3)、86.2%氧化亚铜WP:80%代森锰锌WP(2:8、7:3、9:1)对链格孢菌的抑制效果表现为增效作用,eC50分别为22.29、21.48、37.58、95.68μg/m L,CTC分别为237.03、134.25、169.05、127.89。86.2%氧化亚铜WP:70%霉灵SP(7:3)的防病效果最好,离体防效中保护作用、治疗作用防效分别为86.13%、78.21%,田间防效为75.21%,持效期为7 d,且对兰州百合安全。本试验发现,86.2%氧化亚铜WP与70%霉灵SP以7:3混配后,对百合叶斑病防治效果最高,持效期最长,可用于田间防治。

关键词：矿物源农药化学农药混配百合叶斑病防治效果持效期