Results 91 to 100 of about 56,261 (228)

Differences in characteristics between naturalized threatened plants and other threatened plants

open access: yesConservation Biology, EarlyView.
Abstract Many non‐native plant species introduced by humans have become naturalized. At the same time many species are threatened in their native range. However, the number of plant species threatened in their native range that are naturalized elsewhere remains unknown.
Weihan Zhao   +10 more
wiley   +1 more source

Comprehensive framework for assessing and optimizing existing research networks

open access: yesConservation Biology, EarlyView.
Abstract Conservation, monitoring, and research networks, or collections of ecological research sites unified under a common mission of data collection or a research mission, are essential infrastructure for understanding large landscapes. However, most networks developed opportunistically over decades rather than through systematic design, creating ...
Alyson East   +2 more
wiley   +1 more source

考虑多因素的棒形悬式复合绝缘子老化评估研究

open access: yesGaoya dianqi, 2018
综合考虑复合绝缘子在运行中表现出来的各种老化特性,客观评估其老化程度是保障复合绝缘子安全运行的关键。为此,提出一种复合绝缘子的老化评估模型,将复合绝缘子试品的外观检查试验、憎水性试验、红外测温试验结果作为评估模型的输入参数,对复合绝缘子试品进行老化评估,发现2号复合绝缘子老化程度最重,建议退出运行;1号复合绝缘子老化程度最轻;而3号复合绝缘子老化程度一般,需要跟踪监测。最后通过扫描电镜试验和傅里叶红外光谱试验,验证了评估结果的正确性,说明文中提出的评估模型对于复合绝缘子的老化评估具有一定的意义。
胡雯, 赵淳
doaj  

一种基于未确知测度理论的油纸绝缘老化评估方法

open access: yesGaoya dianqi, 2022
依据油纸绝缘时域介电响应介电谱及其能量谱,定义了两个能反映油纸绝缘老化程度的新特征量——去极化能量初始斜率SW和去极化能量半衰期thalf。通过测试样本分析确定了SW、thalf与油纸绝缘老化程度之间的关联性,验证了其作为绝缘老化指标在油纸绝缘老化评估中的有效性。针对复合油纸绝缘介电特征量,提出了一种新的未确知测度理论的绝缘老化特征指标综合评估体系。建立了绝缘老化评估结构层次与评价指标分级区间,在复合特征指标的权重分析基础上,引入未确知测度理论,针对其中等级评定环节的主观性问题 ...
舒恺, 高飞翎, 余萃卓, 苏凯强
doaj  

Design and Implementation of Traffic Accident Information System for Kunming City [PDF]

open access: yes, 2016
进入21世纪,我国经济快速增长,车流、人流、物流均大幅度增长,道路供需矛盾日趋突出,市政道路建设、规划建设相对滞后,交通流量组织不够科学,路网布局不尽合理,广大交通参与者交通安全意识普遍不高,重、特大事故不断发生,全国每年都有约10万余人死于道路交通事故。交通事故处理作为公安交通管理部门的一项专有职责,对于化解因交通事故所引发的社会矛盾,深入推动和谐交通建设具有举足轻重的意义。因此,交通事故处理信息系统可以帮助公安交通部门管理交通事故信息,是与群众联系的窗口 ...
王丹雯
core  

Global overview of progress in respecting the contributions of traditional knowledge in biodiversity governance

open access: yesConservation Biology, EarlyView.
Abstract Recognition and engagement of Indigenous Peoples and local communities (IP&LCs) and other traditional knowledge (TK) holders in formal biodiversity governance remain limited, despite their significant contribution to the conservation and sustainable use of biodiversity through their knowledge, innovations, practices, and land stewardship.
Kinga Öllerer   +8 more
wiley   +1 more source

Design and Implementation of Wireless Broadband Speed Test System [PDF]

open access: yes, 2014
目前信息产业已发展成为中国经济的先导产业和支柱产业。据中国互联网络信息中心最新报告显示,截至2012年6月底,中国网民数量达到5.38亿,是15年前的867倍。中国宽带用户数达到1.58亿,位列全球第一。互联网普及率为39.9%。IPv6地址数比上年底增长33%,仅次于巴西和美国位列全球第三。我国手机网民数量大幅上升,达到3.88亿,手机首次超越台式电脑成为第一大上网终端。与此同时,无线宽带的用户人数也飞速增加,因此解决无线宽带网络的测速分析及维护成为了运营商迫切需要解决的当务之急 ...
孙旭初
core  

Representation of obligate groundwater‐dwelling copepod diversity in European protected areas

open access: yesConservation Biology, EarlyView.
Abstract Groundwaters sustain diverse surface ecosystems and are populated by metazoan species, mostly invertebrates, that provide fundamental ecological functions and are often of prominent conservation value due to narrow endemism and high phylogenetic rarity.
Francesco Cerasoli   +7 more
wiley   +1 more source

流域泥石流防治的社会效益评估模型研究

open access: yesShuitu Baochi Xuebao, 1995
在流域泥石流防治社会效益评估指标研究的基础上,重点探讨了泥石流防治社会效益的主要评估指选取和6个主要评估指的量化问题,并建立了相应的数学模型。
李华容 唐晓春
doaj   +2 more sources

基于传输性能指标预测的光缆可用性评估

open access: yesGuangtongxin yanjiu, 2016
为准确评估既设光缆未来任务时间是否适用于高性能光端传输设备,提出一种基于传输性能指标预测的光缆可用性评估方法。在构建组合模型准确预测光缆性能指标的基础上,根据光端设备对线路允许损耗变化范围的要求评估光缆的可用性。通过实例验证说明了基于性能指标预测的光缆可用性评估方法的准确性和有效性,对解决光缆可用性评估问题具有一定的参考价值和指导意义。
傅蕾   +5 more
doaj  

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