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Efficient slope reliability and sensitivity analysis using quantile-based first-order second-moment method

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第10期16卷 4192-4203页

作者： Zhiyong Yang Chengchuan Yin xueyou li Shuihua Jiang Dianqing li School of Civil Engineering Sun Yat-Sen UniversityZhuhaiChina Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiChina School of Infrastructure Engineering Nanchang UniversityNanchang330031China State Key Laboratory of Water Resources and Hydropower Engineering Science Institute of Engineering Risk and Disaster PreventionWuhan UniversityWuhan430072China

This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method(QFOSM).The core principles of the QFOSM are elucidated geometrically from the perspective of expanding *** on this geometric interpretation,the QFOSM is further extended to estimate sensitivity indices and assess the significance of various uncertain parameters involved in the slope *** proposed method has the advantage of computational simplicity,akin to the conventional first-order second-moment method(FOSM),while providing estimation accuracy close to that of the first-order reliability method(FORM).Its performance is demonstrated with a numerical example and three slope *** results show that the proposed method can efficiently estimate the slope reliability and simultaneously evaluate the sensitivity of the uncertain *** proposed method does not involve complex optimization or iteration required by the *** can provide a valuable complement to the existing approximate reliability analysis methods,offering rapid sensitivity evaluation and slope reliability analysis.

关键词： Slope reliability Sensitivity analysis Quantile First-order second-moment method(FOSM) First-order reliability method(FORM)

Spatiotemporal distribution of an endangered large-sized ungulate in a high-biodiversity region

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Spatiotemporal distribution of an endangered large-sized ung...

linking camera trapping with multispecies hierarchical occupancy modeling to evaluate diversity and distribution of rare cryptic species across landscapes

第十三届全国野生动物生态与资源保护学术研讨会暨第六届中国西部动物学学术研讨会

作者： xueyou li Xuelong Jiang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences

Understanding spatiotemporal distribution of species is fundamental for both theoretical and practical *** on presence-only species distribution model and camera trapping events,we assessed spatiotemporal distribution of the poorly studied Mishmi takin to map potential distribution of the species in the Dulongjiang Region,a hotspot for *** try to identify the key factors relevant to takin distribution and to explore

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Linking camera trapping with multispecies hierarchical occup...

第十三届全国野生动物生态与资源保护学术研讨会暨第六届中国西部动物学学术研讨会

作者： xueyou li Xuelong Jiang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences

Assessing species distribution and biodiversity patterns are fundamental for prioritizing conservation ***,such work can be challenging for rare or cryptic species for which survey data are often *** developed Bayesian hierarchical multispecies occupancy model that allow us to obtain estimates for species richness and occupancy based on combining camera trapping data from three landscapes:alpine and subalpine

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岩溶地区超长桩基的竖向承载特性

铁道建筑 2023年第6期63卷 89-93页

作者：李学友中铁二局第四工程有限公司成都610031

以南玉铁路(南宁—玉林)跨黎湛特大桥桩基建设为工程背景,采用PLAXIS建立有限元模型进行数值模拟,探讨有无溶洞发育地层条件下超长桩基工作特性。结果表明:岩溶发育时桩基容许承载力比无溶洞时削弱22.2%,溶洞一定程度上减弱了地基刚度,... 详细信息

以南玉铁路(南宁—玉林)跨黎湛特大桥桩基建设为工程背景,采用PLAXIS建立有限元模型进行数值模拟,探讨有无溶洞发育地层条件下超长桩基工作特性。结果表明:岩溶发育时桩基容许承载力比无溶洞时削弱22.2%,溶洞一定程度上减弱了地基刚度,同时造成复杂应力重分布现象;有溶洞发育地基中桩身轴力除出现局部增大现象外,相同荷载下其桩底轴力是无溶洞地基的2倍左右;无溶洞时,地基中位移等值线呈盆状对称分布,有溶洞时等值线在溶洞周围局部弯折,地基中溶洞不对称分布会加剧桩身轴力分布的不均匀性,进而可能导致桩基局部失效。工程中应对串珠状溶洞进行加固处理以提高地基承载力,进而保障桥梁桩基正常使用。

关键词：桥梁桩基岩溶超长桩基承载特性数值模拟桩侧摩阻力

Untangling key predictors of terrestrial mammal diversity patterns in Kenya: implications for protected areas management

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Untangling key predictors of terrestrial mammal diversity pa...

干寒大温差下早龄期混凝土收缩特性及防裂技术

第十六届全国野生动物生态与资源保护学术研讨会

作者： Kenneth Otieno Onditi xueyou li Wenyu Song Quan li Simon Musila James Mathenge Esther Kioko Xuelong Jiang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences Kunming College of life Sciences University of Chinese Academy of Sciences Department of Zoology National Museums of Kenya Sino-Africa Joint Research Centre Chinese Academy of Sciences

The global proliferation of protected areas(PAs) is an enduring means of combating biodiversity declines and was a commendable tool towards achieving Aichi Biodiversity Target 11. Even so, the effectiveness of PAs in conserving biodiversity remains debated due to continued species declines and ecosystem degradations within them. It is increasingly recognized that merely designating new and expanding existing PAs does not guarantee the protection of critical ecosystems and species. Instead, their management must be effective for meaningful long-term conservational success and viability, integral to the success of the historic Kunming-Montreal Global Biodiversity Framework goals and targets. Evaluating the effectiveness of biodiversity management tools such as PAs requires a good understanding of how institutional(such as PA governances and designations) and noninstitutional(such as abiotic [environmental and anthropogenic] factors) variables affect species diversity and distribution patterns and ecological-evolutionary opportunities, especially in biodiversity-rich countries such as Kenya. In this study, we coupled data on Kenya's terrestrial mammal occurrences, phylogenetic associations, functional traits, and abiotic factors to derive multiple taxonomic, functional, and phylogenetic diversity indices. We then inferred PAs' management effectiveness based on the diversity and distribution patterns, their association with governance and designation types, and with several abiotic factors using multivariate statistics and regression analysis. We found that nearly all terrestrial mammals in Kenya were represented in at least one PA(≈ 98%), although the range proportion overlapping in PAs was low. Spatial conservation prioritization analysis showed that a best-solution reserve system required significant expansion of current PAs to achieve a one-third coverage of focal species ranges. Among the diversity indices, species richness was weakly associated with the phylogenet

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西南交通大学学报 2023年第6期58卷 1405-1412页

作者：李福海文涛唐慧琪李继芸李瑞陈昭李学友李超西南交通大学土木工程学院四川成都610031 中铁二局集团有限公司中国建筑第四工程有限公司四川成都610031

为探究干寒大温差下早龄期混凝土收缩变形规律,降低开裂风险,采用3种养护方法对混凝土进行早龄期养护,以抗压强度、劈裂抗拉强度、自由收缩率及最大约束应力为表征手段,设置了基本力学性能试验、自由收缩试验与约束收缩试验,并采用综合... 详细信息

为探究干寒大温差下早龄期混凝土收缩变形规律,降低开裂风险,采用3种养护方法对混凝土进行早龄期养护,以抗压强度、劈裂抗拉强度、自由收缩率及最大约束应力为表征手段,设置了基本力学性能试验、自由收缩试验与约束收缩试验,并采用综合型多指标的灰色关联法分析了不同养护方式下混凝土的抗裂性能.同时,设计了纳米涂层保温性能试验,探究其对混凝土的保温隔热性能.试验结果表明:在-20.0~15.0℃的循环温度中,采用纳米涂层使得圆柱体混凝土试件内部平均温差降低2.95℃;相比于标准养护,3种养护方式下混凝土抗压及劈裂抗拉强度均有显著降低,干寒大温差不利于混凝土的强度发展;自由收缩率随温度变化明显,呈现出温度降低,自由收缩率增大,反之,温度升高自由收缩率减小,并在-20.0℃与15.0℃时出现极值;最大约束应力受到养护方式影响,自然养护下最大约束应力发展最快,终值最大,薄膜养护次之,涂层养护最大约束应力发展最慢,终值最小;涂层养护下灰色关联度高达0.914 9,明显高于自然养护与薄膜养护,表现出优异的抗裂性能.

关键词：早龄期混凝土养护方式强度收缩抗裂性能

基于强度折减采样与高斯过程回归的空间变异土坡自适应可靠度分析

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岩土工程学报 2024年第5期46卷 978-987页

作者：刘亚栋刘贤黎学优杨智勇中山大学土木工程学院广东广州510275 南方海洋科学与工程广东省实验室(珠海) 广东珠海519082 广州市建筑科学研究院集团有限公司广东广州510440

土体参数空间变异性对土坡稳定性的影响已受到岩土工程界的广泛关注,繁冗的计算量是空间变异土坡可靠度分析面临的瓶颈问题。基于强度折减采样(SRS)和高斯过程回归(GPR)模型,提出一种适用于高维空间的空间变异土坡自适应可靠度分析方法(... 详细信息

土体参数空间变异性对土坡稳定性的影响已受到岩土工程界的广泛关注,繁冗的计算量是空间变异土坡可靠度分析面临的瓶颈问题。基于强度折减采样(SRS)和高斯过程回归(GPR)模型,提出一种适用于高维空间的空间变异土坡自适应可靠度分析方法(SRS-GPR)。首先采用Karhunen-Loève展开法将空间变异土体强度参数离散为高维随机变量,随后根据SRS生成土坡临界样本点,接着通过GPR构建土体参数随机场与边坡安全系数之间的高维非线性函数关系,并基于主动学习策略自动搜寻最优训练样本点,迭代更新GPR模型。在此基础上,结合GPR模型和蒙特卡洛模拟进行边坡可靠度分析。最后,通过两个典型算例验证所提方法的准确性、高效性、鲁棒性和适用性。结果表明:所提方法可有效识别靠近极限状态面附近的最优样本点,使得迭代更新的GPR模型在该区域的预测精度逐渐提高。此外,所提方法不受随机变量维度的影响,可直接在高维参数空间应用,且对边坡稳定性模型的调用次数较少,在计算效率方面具有显著优势。

关键词：强度折减采样高斯过程回归自适应可靠度分析高维空间空间变异性

人力资源管理在煤矿辅助运输区队的应用与实践

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神华科技 2019年第12期17卷 88-92页

作者：李学有国家能源集团宁夏煤业有限责任公司梅花井煤矿宁夏灵武751405

针对国家能源集团宁夏煤业有限责任公司梅花井煤矿现状,以生产业务运输一队人力资源优化为例,分析了当前运输一队人力资源方面存在的问题,总结了企业人力资源优化改进方向,提出了人力资源节约方案,并总结其产生效益,以期为同类工作提供... 详细信息

针对国家能源集团宁夏煤业有限责任公司梅花井煤矿现状,以生产业务运输一队人力资源优化为例,分析了当前运输一队人力资源方面存在的问题,总结了企业人力资源优化改进方向,提出了人力资源节约方案,并总结其产生效益,以期为同类工作提供经验借鉴。

关键词：人力资源优化替代效应设备全生命周期远程集中控制减人增效

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WJ1165型胶辊提高纺纱质量的实践

纺织器材 2013年第A03期40卷 28-29页

作者：李学有天津天纺投资控股有限公司天津300308

胶辊的性能和适纺性是决定成纱质量的关键,通过应用WJ1165型低硬度高弹性铝衬管免处理胶辊进行试纺,并与国内某大厂同硬度铝衬管免处理胶辊进行纺纱对比,结果表明,WJ1165型胶辊适纺范围广、纺纱性能优越,在提高成纱条干,降低粗、细节方... 详细信息

胶辊的性能和适纺性是决定成纱质量的关键,通过应用WJ1165型低硬度高弹性铝衬管免处理胶辊进行试纺,并与国内某大厂同硬度铝衬管免处理胶辊进行纺纱对比,结果表明,WJ1165型胶辊适纺范围广、纺纱性能优越,在提高成纱条干,降低粗、细节方面效果显著;结合实际应用,介绍了WJ1165型胶辊的制作、磨砺工艺及注意事项。

关键词： WJ1165型胶辊低硬度制作磨砺成纱质量