Results 11 to 20 of about 1,078,321 (193)
Jianzhu Gangjiegou Jinzhan, 2010 针对5种典型单层球面网壳结构型式（联方型、施威德勒型、凯威特型、三向格子型和短程线型）,本文采用基于离散变量的序列两级截面优化算法对一百个不同跨度（30m60m）、不同矢高（1/31/7）的网壳进行截面优化设计,在截面优化设计结果中提取选型所需的优秀样本,一个优秀样本由3部分组成:跨度,矢跨比和该跨度、矢跨比下用钢量最少的网壳结构类型;然后利用BP人工神经网络对复杂非线性映射关系的模拟能力建立网壳跨度、矢跨比与用钢量最少的网壳型式之间的映射关系,避免了结构选型优化的多维、多重非线性模型的求解困难 ...
陈世英, 郭玉霞, 鹿晓阳
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Jianzhu Gangjiegou Jinzhan, 2022 提出了一个考虑内力重分布影响的高层结构减震构件单步优化法，为高层结构减震构件的优化设计提供了一个单步、高效的方法。首先，考察了内力重分布对单自由度并联体系比虚应变能的影响规律。然后提出了考虑并联关系的目标比虚应变能修正系数用以解决已有的单步优化法没有考虑超静定结构内力重分布的问题，并用算例说明优化结果的合理性。然后，作者用非减震构件的单步优化法去优化减震构件，并结合减震性能曲线提出了考虑内力重分布影响的高层结构的减震构件的单步优化法。最后通过算例对所提出的优化法进行验证 ...
陈荣 +4 more
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Jianzhu Gangjiegou Jinzhan, 2023 为实现网壳各节点抵抗荷载能力的均匀分布，提升结构稳定承载力，基于网壳结构受力特点，引入了单层网壳结构的杆件构形刚度参数。以结构杆件构形刚度均匀化为目标，将网壳杆件截面尺寸作为优化变量，采用惯性权重改进后的粒子群算法对网壳的杆件截面进行优化配置。优化结果表明，构形刚度方差能较为准确地反映结构的杆件构形刚度均匀程度。通过粒子群算法优化后求得的杆件配置可以使网壳结构接近于等稳定性，最大程度地提升结构的稳定极限承载力。
张澜, 孙建恒, 史若琪, 王军林
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Gaoya dianqi, 2020 结构小型化和高绝缘水平的优化设计是固封极柱设计中的重要组成部分。以40.5 kV高海拔穿墙式固封极柱为例,通过对普通结构、外绝缘加高结构、伞裙优化与屏蔽优化相结合等不同结构形式的固封极柱的电场进行分析,实现了绝缘结构的最优化。解决了40.5 kV高海拔穿墙式固封极柱的绝缘问题和局部放电问题,为类似40.5 kV穿墙式固封极柱的绝缘结构优化提供了参考。
李红梅, 王志川, 刘玉春
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Gaoya dianqi, 2021 针对高压直流断路器的电磁斥力机构,提出了一种优化机构结构参数的方法。首先运用场路耦合方法对电磁斥力机构建立模型,利用有限元方法进行电磁场计算,分析了斥力盘结构参数、线圈结构参数、放电电容电容值和预充电压变化对动态特性的影响。以电流峰值、电磁斥力峰值、2 ms时刻位移值和速度值作为目标函数,利用神经网络算法,拟合了斥力机构结构参数与目标函数之间的关系,从而对斥力机构的结构进行了优化设计。优化结果表明,在不增大2 ms时刻运动速度条件下,初始运动速度和2 ms时刻位移均得到提高,改善了机构的动态性能 ...
孟洲恬, 淡淑恒
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Wildlife Letters, EarlyView.Human‐caused leopard deaths in Sri Lanka averaged 9.65 ± 4.5 records year−1 over 17 years (2008–2024; n = 164), with records highly clustered in the central highland mosaic ecosystem. Mortality was dominated by adult males and driven primarily by snaring in plantation landscapes, and indicating an increase approximately 0.7–0.8 deaths per year.
Sanjaya Weerakkody +11 more
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Gaoya dianqi, 2022 针对因真空断路器大电流故障开断过程中灭弧室断口场域磁感应强度弱，导致磁场对电弧等离子体有效控制力减弱的问题，将NSPSO多目标优化方法与磁场有限元分析相结合，以12 kV/1 250 A/31.5 kA典型技术参数的中压真空断路器灭弧室纵磁触头系统为对象进行结构优化设计，以触头片开槽长度、斜槽深度、触头片开槽偏转角、触头杯座厚度为优化设计变量，以灭弧室断口中心截面纵磁最大值与磁场有效作用面积同时达到最大值为优化设计目标，求得Pareto前沿非支配优化解集 ...
臧谦 +6 more
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Conservation Biology, EarlyView.Abstract Constructed value of information (CVoI) is an expert elicitation decision‐analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation
Kristin P. Davis +7 more
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Perceived costs as drivers of wildlife management preferences in rural Tanzanian communities
Conservation Biology, EarlyView.Abstract Effectively managing human–wildlife interactions is crucial for fostering coexistence on shared landscapes. Management options are most effective when aligned with the preferences of people directly affected by wildlife, yet little is known about how socioecological factors influence these preferences.
Christian Kiffner +10 more
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Structured machine learning modeling to support conservation of deep‐sea benthic biodiversity
Conservation Biology, EarlyView.Abstract Biodiversity monitoring programs need to deliver accurate, timely, and actionable predictions. To establish a predictive monitoring program for deep‐sea benthos of the Santos Basin, Brazil, we developed a two‐stage structured model that allowed comparison of biodiversity predictions obtained from environmental simulations (2M‐Sim).
Gustavo Fonseca +23 more
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