Based on two-dimensional （2D） rigid-plastic finite element （FE） method, the optimum observation area for metallographic microstructure and the influence of the height-diameter ratio on which were analyzed for the ...Based on two-dimensional （2D） rigid-plastic finite element （FE） method, the optimum observation area for metallographic microstructure and the influence of the height-diameter ratio on which were analyzed for the cylindrical samples with the diameter of 8 mm and different heights from 8 to 16 mm in nonuniform compressive experiments. It is shown that the representative metallographic observation area relevant to the applied deformation condition is located at about 0.835 of the radius from the center of the sample to the solder joint between the sample and the thermocouples. At the same time, the microstructure in that area is more appropriate as the height of the sample is 12 mm. The related parameters of GH4033 superalloy were adopted in the FE analysis, and the validity of this analysis was verified by the compressive experiments.展开更多
快速轨道反馈(Fast Orbital Feedback,FOFB)系统是影响高能同步辐射光源(High Energy Photon Source,HEPS)轨道稳定性的重要因素之一,在设计时应尽可能提高FOFB系统的有效反馈带宽。基于该需求,为HEPS的FOFB系统设计了两层环路集中计算...快速轨道反馈(Fast Orbital Feedback,FOFB)系统是影响高能同步辐射光源(High Energy Photon Source,HEPS)轨道稳定性的重要因素之一,在设计时应尽可能提高FOFB系统的有效反馈带宽。基于该需求,为HEPS的FOFB系统设计了两层环路集中计算式的系统网络拓扑结构,并在此基础上设计完成了FOFB系统信号传输链路的可编程阵列逻辑(Field Programmable Gate Array,FPGA)固件算法逻辑,内容包括束流位置获取、环路数据传输、FOFB算法、电源控制接口以及系统测试等多个部分。经实验室测试验证,当前结构下的FOFB系统总延迟时间约为140μs,满足HEPS装置对FOFB系统有效反馈带宽的需求。展开更多
目的探讨脂联素水平在β1-肾上腺素受体自身抗体(autoantibodies against the second extra-cellular loop of theβ1-adrenoceptor,β1-AA)诱导糖尿病发生发展中的作用。方法收集45例诊断糖尿病患者和42例健康体检者的血清,ELISA法检...目的探讨脂联素水平在β1-肾上腺素受体自身抗体(autoantibodies against the second extra-cellular loop of theβ1-adrenoceptor,β1-AA)诱导糖尿病发生发展中的作用。方法收集45例诊断糖尿病患者和42例健康体检者的血清,ELISA法检测血清中β1-AA及脂联素水平;建立β1-AA主动免疫小鼠模型,动态检测小鼠血糖变化;标记法芯片技术筛选主动免疫模型小鼠外周血清中发生改变的细胞因子,进一步从大体及细胞水平进行验证。结果与健康体检者相比,糖尿病患者血清β1-AA效价及阳性率均增高[(0.82±0.31)vs.(0.12±0.10),57.7%vs.0.1%,P<0.001],脂联素水平降低[(0.19±0.09)vs.(1.08±0.62),P<0.001];主动免疫8周时,免疫组小鼠空腹血糖明显高于对照组[(14.0±0.81)mmol/L vs.(5.03±0.21)mmol/L,P<0.001)],且空腹葡萄糖耐量试验呈阳性;芯片结果显示,主动免疫8周时,小鼠外周血清中脂联素水平显著低于对照组(变化比值>100);蛋白免疫印迹法和实时荧光定量聚合酶链反应显示,主动免疫8周脂肪组织脂联素蛋白及mRNA水平均低于对照组;细胞实验发现,β1-AA刺激后,3T3-L1细胞脂联素分泌减少。结论脂联素在β1-AA诱导的糖尿病发生发挥重要作用。展开更多
Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theo...Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theory exploring the signal sparsity representation, which has been proved to be superior for the DOA estimation. However, the spatial aliasing and the offset at endfire are the main obstacles for CS applied in the wideband DOA estimation. We propose a particle filter based compressive sensing method for tracking moving wideband sound sources. First, the initial DOA estimates are obtained by wideband CS algorithms. Then, the real sources are approximated by a set of particles with different weights assigned. The kernel density estimator is used as the likelihood function of particle filter. We present the results for both uniform and random linear array. Simulation results show that the spatial aliasing is disappeared and the offset at endfire is reduced. We show that the proposed method can achieve satisfactory tracking performance regardless of using uniform or random linear array.展开更多
基金supported by the National Natural Science Foundation of China (No. 51274062)
文摘Based on two-dimensional （2D） rigid-plastic finite element （FE） method, the optimum observation area for metallographic microstructure and the influence of the height-diameter ratio on which were analyzed for the cylindrical samples with the diameter of 8 mm and different heights from 8 to 16 mm in nonuniform compressive experiments. It is shown that the representative metallographic observation area relevant to the applied deformation condition is located at about 0.835 of the radius from the center of the sample to the solder joint between the sample and the thermocouples. At the same time, the microstructure in that area is more appropriate as the height of the sample is 12 mm. The related parameters of GH4033 superalloy were adopted in the FE analysis, and the validity of this analysis was verified by the compressive experiments.
文摘快速轨道反馈(Fast Orbital Feedback,FOFB)系统是影响高能同步辐射光源(High Energy Photon Source,HEPS)轨道稳定性的重要因素之一,在设计时应尽可能提高FOFB系统的有效反馈带宽。基于该需求,为HEPS的FOFB系统设计了两层环路集中计算式的系统网络拓扑结构,并在此基础上设计完成了FOFB系统信号传输链路的可编程阵列逻辑(Field Programmable Gate Array,FPGA)固件算法逻辑,内容包括束流位置获取、环路数据传输、FOFB算法、电源控制接口以及系统测试等多个部分。经实验室测试验证,当前结构下的FOFB系统总延迟时间约为140μs,满足HEPS装置对FOFB系统有效反馈带宽的需求。
文摘目的探讨脂联素水平在β1-肾上腺素受体自身抗体(autoantibodies against the second extra-cellular loop of theβ1-adrenoceptor,β1-AA)诱导糖尿病发生发展中的作用。方法收集45例诊断糖尿病患者和42例健康体检者的血清,ELISA法检测血清中β1-AA及脂联素水平;建立β1-AA主动免疫小鼠模型,动态检测小鼠血糖变化;标记法芯片技术筛选主动免疫模型小鼠外周血清中发生改变的细胞因子,进一步从大体及细胞水平进行验证。结果与健康体检者相比,糖尿病患者血清β1-AA效价及阳性率均增高[(0.82±0.31)vs.(0.12±0.10),57.7%vs.0.1%,P<0.001],脂联素水平降低[(0.19±0.09)vs.(1.08±0.62),P<0.001];主动免疫8周时,免疫组小鼠空腹血糖明显高于对照组[(14.0±0.81)mmol/L vs.(5.03±0.21)mmol/L,P<0.001)],且空腹葡萄糖耐量试验呈阳性;芯片结果显示,主动免疫8周时,小鼠外周血清中脂联素水平显著低于对照组(变化比值>100);蛋白免疫印迹法和实时荧光定量聚合酶链反应显示,主动免疫8周脂肪组织脂联素蛋白及mRNA水平均低于对照组;细胞实验发现,β1-AA刺激后,3T3-L1细胞脂联素分泌减少。结论脂联素在β1-AA诱导的糖尿病发生发挥重要作用。
基金supported by the NFSC Grants 51375385 and 51675425Natural Science Basic Research Plan in Shaanxi Province of China Grants 2016JZ013
文摘Tracking moving wideband sound sources is one of the most challenging issues in the acoustic array signal processing which is based on the direction of arrival(DOA) estimation. Compressive sensing(CS) is a recent theory exploring the signal sparsity representation, which has been proved to be superior for the DOA estimation. However, the spatial aliasing and the offset at endfire are the main obstacles for CS applied in the wideband DOA estimation. We propose a particle filter based compressive sensing method for tracking moving wideband sound sources. First, the initial DOA estimates are obtained by wideband CS algorithms. Then, the real sources are approximated by a set of particles with different weights assigned. The kernel density estimator is used as the likelihood function of particle filter. We present the results for both uniform and random linear array. Simulation results show that the spatial aliasing is disappeared and the offset at endfire is reduced. We show that the proposed method can achieve satisfactory tracking performance regardless of using uniform or random linear array.
