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Conserving our global botanical heritage:The PSESP plant conservation program

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Plant Diversity 2020年第4期42卷 319-322页

作者： Peter crane Oak Spring Garden Foundation 1776 Loughborough LaneUppervilleVA20184USA School of Forestry and Environmental Studies Yale UniversityNew HavenCT06511USA

It is a fundamental truth of ecology that most species are *** this rarity extends beyondmeasures of abundance to geographic *** a global context,very few species are truly abundant,and most are more or less restricted *** the world of plants,where there are several hundred thousand species,the number of species with especially small population sizes and small fragmentary ranges is extremely *** recent assessment,the most exhaustive undertaken so far,based on 200 million observations taken from herbarium records,ecological surveys and other sources,suggests that of the more than 400,000 species of land plants,ca.36%are“exceedingly rare”(Enquist et al.,2019).

关键词： Plants Conservation Paleobotany PSESP program

A Wavelet-Based Method to Measure Stock Market Development

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Open Journal of Statistics 2014年第1期4卷 89-96页

作者： Adel al Sharkasi Heather J. Ruskin Martin crane José Matos Sílvio M. A. Gama CMUP & Departamento de Matemática Aplicada Faculdade de Ciencias Universidade do Porto Porto Portugal CMUP & Grupo de Matemática Informática Faculdade de Econmia Universidade do Porto Porto Portugal Department of Statistics Faculty of Science University of Benghazi Benghazi Libya School of Computing Dublin City University Dublin Ireland

In this paper, we introduce a novel algorithm, based on the wavelet transform, to measure stock market development. This algorithm is applied to the return series of fourteen worldwide market indices from 1996 to 2005. We find that a comparison of the return series in terms of the quantity of fractional Gaussian noise (fGn), for different values of Hurst exponent (H), facilitates the classification of stock markets according to their degree of development. We also observe that the simple classification of stock markets into “emerging” or “developing” and “mature” or “developed” is no longer sufficient. However, stock markets can be grouped into three categories that we named emerging, intermediate and mature.

关键词： Wavelet Transform Hurst Exponent (H) Stock Market Classifications

Deployment of Self-Propelled Modular Transporter for Vessel Installation

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Open Journal of Civil Engineering 2022年第4期12卷 554-558页

作者： Michael A. Stogdill Mohammad K. al-Dossary Nezar H. al-Khalifah Project Management Team—OFPD/SCIPD Saudi Aramco Dhahran Kingdom of Saudi Arabia

The traditional way of installing large vessels has always been to employ the use of cranes. The Water Handling Debottlenecking Project team has, instead, made use of a different technology—employing a Self-Propelled Modular Transporter (SPMT) to install nine vessels in situ. These SPMT units have many advantages over crane installations, such as safety and efficiency, not to mention lower costs due to their self-propelled capabilities.

关键词： Self-Propelled Modular Transporter (SPMT) Transportation Vessel Transportation Vessel Installation Horizontal Vessel

Design of Fuzzy PD-Controlled Overhead crane System with Anti-Swing Compensation

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Engineering（科研） 2011年第7期3卷 755-762页

作者： Shebel Asad Maazouz Salahat Mohammed Abu Zalata Mohammad alia Ayman al Rawashdeh 不详

This work aimed to find a proper control strategy to transfer loads using overhead cranes. The proposed control strategy, which is Fuzzy PD-based, should take into account two main factors. First, the time needed to move the payload from the initial pick up point to the destination point that must be minimized. Second, the oscillation of the payload must be reduced to prevent hazards for people and equipment in the work place. The current work, presents a comparative analysis of fuzzy PD based control basing on classical PD approach. A simplified model has been derived. The proposed control techniques have been designed and validated with MatLab. Numerical comparative results have been obtained and discussed.

关键词： Induction Motor Modeling Stationary Reference Frame Matlab/Simulink

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竖井门式起重机制造关键技术分析

河南机电高等专科学校学报 2017年第2期25卷 17-20,74页

作者：李翔赵敬云刘传贺新乡市起重设备厂有限责任公司河南新乡453000 河南工学院河南新乡453003

针对水电站深大竖井建设中所使用的传统提升设备进行了分析,指出传统设备使用和功能上的诸多缺点。详细论述了竖井门式起重机制造过程中所采用的多种关键技术,试用表明竖井门式起重机样机能够满足深大竖井建设工况要求,在安全和提升工... 详细信息

针对水电站深大竖井建设中所使用的传统提升设备进行了分析,指出传统设备使用和功能上的诸多缺点。详细论述了竖井门式起重机制造过程中所采用的多种关键技术,试用表明竖井门式起重机样机能够满足深大竖井建设工况要求,在安全和提升工作效率方面有着突出优势和良好的应用前景。

关键词：竖井门式起重机冗余绳系抗旋转载人吊笼

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潼关吊机两用水文测量船设计

武汉造船 2001年第3期 9-11页

作者：刘家新董元胜龚昌奇于明澜武汉理工大学武汉430063

介绍了黄河潼关吊机两用水文测量船的主要参数确定 ,适应黄河浅水。

关键词：水文测量船主尺度型线布置设计特点

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新技术在焦化装置中的应用

石油化工设备技术 2003年第4期24卷 24-28,31页

作者：李锋滕春红赵岩张强闻明科中国石油锦西石化分公司辽宁葫芦岛125001

在焦化装置中能够长周期运行且应用较好的几种新设备、新技术:水力除焦程控系统改造;5T桥式抓斗起重机改装频敏变阻器;外环流转子式凸轮泵及双螺杆泵的应用;DCS集散控制系统。

关键词：新技术程控系统频敏变阻器 DCS系统凸轮泵螺杆泵应用

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试论N1002型100t铁路起重机改造

铁道车辆 2003年第2期41卷 30-34页

作者：赵秀德范思圣齐齐哈尔铁路车辆(集团)有限责任公司技术中心黑龙江齐齐哈尔161002

对 N10 0 2型 10 0 t铁路起重机的发展过程进行了回顾 ,对其技术水平和各种技术改造方案进行了评述 ,提出了改造建议。

关键词：铁路起重机发展过程技术改造吊车铁路车辆

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塔式起重机吊臂截面设计

山东建筑工程学院学报 2001年第3期16卷 45-48页

作者：曲振波宋世军王积永山东建筑工程学院机械工程系山东济南250014

依据GB/T1375 2— 99《塔式起重机设计规范》 ,提出影响塔式起重机吊臂截面高宽比的参数 ,通过实例说明了在以往塔式起重机吊臂设计中采用的计算公式 :H =Blox2loyAA1对于轴心受压构件是恰当的 ,而对于偏心受压构件存在较大误差。给出... 详细信息

依据GB/T1375 2— 99《塔式起重机设计规范》 ,提出影响塔式起重机吊臂截面高宽比的参数 ,通过实例说明了在以往塔式起重机吊臂设计中采用的计算公式 :H =Blox2loyAA1对于轴心受压构件是恰当的 ,而对于偏心受压构件存在较大误差。给出了一种新的计算方法 ,即根据钢结构设计规范中双向格构式压弯构件的稳定性来确定截面的高度 ,这种方法能够使计算中的受力分析更加符合实际工况 ,因而使设计的塔式起重机吊臂结构优、材料省、可靠性高。

关键词：塔式起重机吊臂截面尺寸计算方法