针对在短期负荷功率预测过程中,因负荷功率波动大而导致单一模型存在预测精度低的问题,提出基于时间特征分析的短期负荷功率NST-IRN组合预测模型。首先,深度挖掘负荷功率的时间特性变化,将其分解为趋势成分以及循环分量,构建新型时间序...针对在短期负荷功率预测过程中,因负荷功率波动大而导致单一模型存在预测精度低的问题,提出基于时间特征分析的短期负荷功率NST-IRN组合预测模型。首先,深度挖掘负荷功率的时间特性变化,将其分解为趋势成分以及循环分量,构建新型时间序列(NTS)模型。其次,考虑多时间尺度输入特征与日类型对负荷功率的影响,构建含特征输入结构与深度学习结构的改进残差神经网络(IRN)模型。最后,利用D-S证据理论对NTS与IRN模型的预测结果进行权重融合,以获取最终负荷预测结果。以ISO New England的真实负荷数据进行仿真实验,结果表明所提模型具有较高的预测精度和鲁棒性。展开更多
A new analytical solution for ground surface settlement induced by deep excavation is proposed based on the elastic half space Melan’s solution,and the analytical model is related to the physical and mechanical prope...A new analytical solution for ground surface settlement induced by deep excavation is proposed based on the elastic half space Melan’s solution,and the analytical model is related to the physical and mechanical properties of soil with the loading and unloading action during excavation process.The change law of earth pressure of the normal consolidation soil after the foundation pit excavation was analyzed,and elastic displacement calculation methods of analytic solution were further established given the influence of excavation and unloading.According to the change of stress state in the excavation process of foundation pit,the planar mechanical analysis model of the foundation excavation problem was established.By combining this model with the physical equations and geometric equations of plane strain problem with consideration of the loading and unloading modulus of soil,constitutive equation of the plane strain problem was also established.The loading and unloading modulus formula was obtained by using the parameter calculation method in Duncan-Chang curve model.The constitutive equation obtained from the model was used to calculate the soil stress state of each point to determine its loading and unloading modulus.Finally,the foundation pit displacement change after excavation was calculated,and thus the soil pressure distribution after retaining structure deformation.The theoretical results calculated by making corresponding programs were applied to engineering practice.By comparing the conventional calculation results with monitoring results,the practicability and feasibility of the calculation model were verified,which should provide a theoretical basis for similar projects.展开更多
Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and atten...Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and attenuates loading4nduced bone formation in perlecan deficient mice(Hypo).Considering that intracellular calcium[Ca2+]i is an ubiquitous messenger controlling numerous cellular processes including mechanotransduction,we hypothesized that perlecan deficiency impairs bone’s calcium signaling in response to loading.To test this,we performed real-time[Ca2+]i imaging on in situ osteocytes of adult murine tibiae under cyclic loading(8 N,Figure 1).Relative to wild type(WT),Hypo osteocytes showed decreases in the overall[Ca2+]i response rate(-58%),calcium peaks(-33%),cells with multiple peaks(-53%),peak magnitude(-6.8%),and recovery speed to baseline(-23%).RNA sequencing and pathway analysis of tibiae from mice subjected to one or seven days of unilateral loading demonstrated that perlecan deficiency significantly suppressed the calcium signaling,ECM-receptor interaction,and focal adhesion pathways following repetitive loading.Defects in the endoplasmic reticulum(ER)calcium cycling regulators such as Ryr1/ryanodine receptors and Atp2a1/Sercal calcium pumps were identified in Hypo bones.Taken together,impaired calcium signaling may contribute to bone’s reduced anabolic response to loading,underlying the osteoporosis risk for the SJS patients.展开更多
文摘针对在短期负荷功率预测过程中,因负荷功率波动大而导致单一模型存在预测精度低的问题,提出基于时间特征分析的短期负荷功率NST-IRN组合预测模型。首先,深度挖掘负荷功率的时间特性变化,将其分解为趋势成分以及循环分量,构建新型时间序列(NTS)模型。其次,考虑多时间尺度输入特征与日类型对负荷功率的影响,构建含特征输入结构与深度学习结构的改进残差神经网络(IRN)模型。最后,利用D-S证据理论对NTS与IRN模型的预测结果进行权重融合,以获取最终负荷预测结果。以ISO New England的真实负荷数据进行仿真实验,结果表明所提模型具有较高的预测精度和鲁棒性。
基金Project(41672290)supported by the National Natural Science Foundation of ChinaProject(2016J01189)supported by the Natural Science foundation of Fujian Province,China
文摘A new analytical solution for ground surface settlement induced by deep excavation is proposed based on the elastic half space Melan’s solution,and the analytical model is related to the physical and mechanical properties of soil with the loading and unloading action during excavation process.The change law of earth pressure of the normal consolidation soil after the foundation pit excavation was analyzed,and elastic displacement calculation methods of analytic solution were further established given the influence of excavation and unloading.According to the change of stress state in the excavation process of foundation pit,the planar mechanical analysis model of the foundation excavation problem was established.By combining this model with the physical equations and geometric equations of plane strain problem with consideration of the loading and unloading modulus of soil,constitutive equation of the plane strain problem was also established.The loading and unloading modulus formula was obtained by using the parameter calculation method in Duncan-Chang curve model.The constitutive equation obtained from the model was used to calculate the soil stress state of each point to determine its loading and unloading modulus.Finally,the foundation pit displacement change after excavation was calculated,and thus the soil pressure distribution after retaining structure deformation.The theoretical results calculated by making corresponding programs were applied to engineering practice.By comparing the conventional calculation results with monitoring results,the practicability and feasibility of the calculation model were verified,which should provide a theoretical basis for similar projects.
基金supported by NIH grants ( P30GM103333,R01AR054385)supported partially by a core access award through NIH NIGMS IDeA Program grant ( P20GM103446)
文摘Perlecan,a heparan sulfate proteoglycan,acts as a mechanical sensor for bone to detect external loading.Deficiency of perlecan increases the risk of osteoporosis in patients with Schwartz-Jampel Syndrome(SJS)and attenuates loading4nduced bone formation in perlecan deficient mice(Hypo).Considering that intracellular calcium[Ca2+]i is an ubiquitous messenger controlling numerous cellular processes including mechanotransduction,we hypothesized that perlecan deficiency impairs bone’s calcium signaling in response to loading.To test this,we performed real-time[Ca2+]i imaging on in situ osteocytes of adult murine tibiae under cyclic loading(8 N,Figure 1).Relative to wild type(WT),Hypo osteocytes showed decreases in the overall[Ca2+]i response rate(-58%),calcium peaks(-33%),cells with multiple peaks(-53%),peak magnitude(-6.8%),and recovery speed to baseline(-23%).RNA sequencing and pathway analysis of tibiae from mice subjected to one or seven days of unilateral loading demonstrated that perlecan deficiency significantly suppressed the calcium signaling,ECM-receptor interaction,and focal adhesion pathways following repetitive loading.Defects in the endoplasmic reticulum(ER)calcium cycling regulators such as Ryr1/ryanodine receptors and Atp2a1/Sercal calcium pumps were identified in Hypo bones.Taken together,impaired calcium signaling may contribute to bone’s reduced anabolic response to loading,underlying the osteoporosis risk for the SJS patients.
