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Zhendong Ceshi yu Zhenduan为了研究大跨屋盖表面风压非高斯特性及极值风压分布，对某高铁站房屋盖进行了风洞测压试验。首先，对表面风压进行高斯分布和非高斯分布的划分；其次，对比3种不同单一概率分布（Gumbel、Lognormal和Weibull）及其对应的组合分布（双Gumbel、双Lognormal和双Weibull）对屋盖表面风压时程的拟合效果，并比较了组合概率分布获取的极值风压与修正Hermite法的估计结果；最后，给出全风向角下屋盖极值风压分布。结果表明：组合概率分布对风压时程的拟合效果优于单一分布 ...
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四川大学学报. 自然科学版, 2004 用血管铸型和组织透明方法观察研究了蓝马鸡(Crossoptilonauritum)心脏左、右冠状动脉的分支分布情况.结果表明,蓝马鸡的心脏由左右冠状动脉营养.左冠状动脉分为前室间隔支、前降支和旋支.前降支又分出动脉圆锥左支,旋支又分出左缘支.前室间隔支分布于室间隔前1/3部,前降支分支分布于左心室前壁、动脉圆锥的左侧部及右心室上部的小部等,旋支分布于左室侧壁、隔壁的部分及左心房等处.右冠状动脉沿途分出后室间隔支、动脉圆锥右支、右室前支及右缘支.后室间隔支分为三支分布于室间隔后2/3部及左右心室的隔壁等 ...
俞诗源 +4 more
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Modeling seed germination data to meet biodiversity conservation needs in the Mediterranean
Conservation Biology, EarlyView.Workflow to assess the availability and quality of germination data and assign species' thermal risk in the Mediterranean. (a) Assessment of data availability, including the phylogenetic distribution of the number of records (i.e. available germination data); (b) data quality assessment; and (c) assignment of climate risk categories for species that ...
Diana María Cruz‐Tejada +2 more
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Dianci bileiqi, 1980 本文研究了具有内部微观结构缺陷的瓷件在单轴向应力状态下强度的维布尔分布,给出δu=0情况下决定维布尔参数的一个图解方法。根据维布尔分布导出抗折瓷件在一定可靠性下极限应力下限值的计算公式,并比较了按维布尔分布和按正态分布计算的在相同可靠性下瓷件极限应力下限值的结果,结果表明按维布尔分布计算的下限位偏于安全。
马功勋, 刘长荣, 陶增炎
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Conservation Biology, EarlyView.Abstract Reversing ongoing biodiversity loss requires effectively managing anthropogenic threats. Although conservation actions can mitigate these threats, prioritizing and targeting such actions remain challenging because species respond differently depending on the nature of the threats and their biological traits.
Camila Guerrero‐Pineda +3 more
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, 1996 椴树属Tilia是椴树科一个形态特殊且唯一的北温带分布属,分布于亚洲、欧洲和北美,构成典型的北温带分布格局,三个分离的分布区之间缺乏共有种。本文对各分布区的种类进行重新评价,确认全属25种。其中东亚17种,占68％,包含了现存种类各个演化阶段的类群,是现代分布中心;欧洲-西西伯利亚6种,属于木果组及壳果组;北美2种,均为木果组成员。化石分布与现代地理分布格局基本相似,但分布纬度较现代分布偏北,达到北纬80°附近,且还出现于现今无椴树分布的亚洲大陆腹地,北美西部椴树至第三纪末完全绝迹 ...
唐亚,诸葛仁, 诸葛仁
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Conservation Biology, EarlyView.Abstract Modeling species distributions in dynamic pelagic environments remains challenging, particularly for wide‐ranging and highly mobile species when there is limited guidance on model performance. This limitation constrains the effective use of species distribution models (SDMs) in marine conservation, where robust and transferable predictions are
E. Pasanisi +32 more
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Dianci bileiqi, 2018 电位分布及温度分布情况是对避雷器健康运行进行评价的重要指标,直接关系到整支避雷器的运行寿命,在无均压措施的情况下,将导致老化速度加快,甚至发生热崩溃。对避雷器的电位分布情况进行测试是对避雷器进行均压的首要条件,但传统检测手段均为基于有线光纤方式进行电位分布采集。本项目基于高性能AVR微处理器,便携式单片微型计算机采样,无线通信,同步采样分析等手段,成功研制了避雷器电位分布及温度分布无线检测系统。对避雷器电位分布及温度分布情况以无线同步方式进行测试,避免了测试现场繁琐的光纤布线 ...
李佳奇 +5 more
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, 2010 【目的】研究不同生境的多枝树柳种群空间分布点格局。多枝柽柳(Tamarix ramosissima)种群在自然界中主要有4种生境分布类型:风沙土生境类型、草甸土生境类型、吐加依土生境类型和盐土生境类型。【方法】采用点格局分析法分析了不同生境中多枝柽柳在不同尺度下的空间分布格局。【结果】①风沙土生境类型,尺度2~7 m以内,其为集群分布,当尺度大于7 m时,则为随机分布;②草甸土生境类型和吐加依土生境类型的柽柳种群,在所有的尺度(t)下,均显著地偏离集群分布,呈随机分布;③盐土生境类型,尺度6~7 m以内,
陈金星, 尹林克
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Subspecies taxonomy reflects social and geographic patterns of taxonomic effort in tetrapods
Conservation Biology, EarlyView.Abstract Subspecies have been used in conservation biology to account for intraspecific patterns in genetic diversity, which is crucial to long‐term population viability. Although over 3200 subspecies are currently assessed by the International Union for Conservation of Nature Red List, their biological relevance remains controversial.
Jhonny J. M. Guedes +3 more
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