In this paper, the cone model is applied to the vibration analysis of two foundations on a layered soil half space. In the analysis, the total stress field in the subsoil is divided into the free-field and the scatter...In this paper, the cone model is applied to the vibration analysis of two foundations on a layered soil half space. In the analysis, the total stress field in the subsoil is divided into the free-field and the scattering field. Seed＇s simplified method is adopted for the free-field analysis, while the cone model is proposed for analyzing the dynamic scattering stress wave field. The shear stress field and the compressive stress field in the layered stratum with two scattering sources are calculated by shear cone and compressive cone, respectively. Furthermore, the stress fields in the subsoil with two foundations are divided into six zones, and the P wave and S wave are analyzed in each zone. Numerical results are provided to illustrate features of the added stress field for two surface foundations under vertical and horizontal sinusoidal force excitation. The proposed cone model may be useful in handling some of the complex problems associated with multi-scattering sources.展开更多
Objective:To investigate the effects of minimally invasive craniotomy combined with edaravone on cerebral oxygen metabolism, cerebrovascular function and oxidative stress in patients with acute cerebral hemorrhage.Met...Objective:To investigate the effects of minimally invasive craniotomy combined with edaravone on cerebral oxygen metabolism, cerebrovascular function and oxidative stress in patients with acute cerebral hemorrhage.Methods:A total of 100 patients with acute cerebral hemorrhage treated in our hospital from March 2015 to February 2017 were randomly divided into control group and observation group. 50 patients in the control group were treated with minimally invasive craniotomy. On the basis of control group, patients in the observation group were treated with edaravone. Cerebral oxygen metabolism, cerebrovascular function and oxidative stress were measured later in both groups.Results:After treatment, the levels of SOD in both groups increased significantly and MDA levels decreased significantly, and SOD level in the observation group was (97.34±1.95) U/mL, which was significantly higher than the control group, MDA level was (2.77±0.11) mol/L and significantly lower than that of the control group after treatment;After treatment, the levels of ET in both groups were significantly lower than those before treatment, and the levels of CGRP were significantly higher than those before treatment. ET level in observation group was (3.24±0.22) μg/L after treatment, which was significantly lower than that in control group (59.67±0.79) pg/mL, which was significantly higher than the control group;After treatment, the levels of SjvO2, CjvO2 and PbtO2 in both groups were significantly increased compared with before treatment, the levels of Da-jvO2 and CEO2 were significantly lower than the level of before treatment, and the levels of SjvO2, The levels of CjvO2 and PbtO2 were (62.93±1.63)%, (99.31±0.94) mL/L and (28.56±1.55) mmHg, which were significantly higher than the control group. Da-jvO2 and CEO2 levels were (51.31±1.13) mL/L and (30.52±0.43)%, which were significantly lower than the control group.Conclusion: Edaravone combined with minimally invasive craniotomy can effectively reduce the level of oxidative stress, improve endothelial function and cerebral oxygen metabolism, and has reliable curative effect. It is worth further clinical application.展开更多
As a new joint structure,the impact of initial imperfection to stress of Concave cone-toroid-cylinder combined shell was analyzed. Firstly the location and shape of combined shell's initial imperfection caused by ...As a new joint structure,the impact of initial imperfection to stress of Concave cone-toroid-cylinder combined shell was analyzed. Firstly the location and shape of combined shell's initial imperfection caused by welding was studied. Secondly dominated stress was chosen after comparing varioustypical stress. Then it was analyzed that the influence of imperfection to dominated stress via changing the shape of frame's deflection and shell's concave-convex. At last the strengthening case for combined shell with imperfection was pointed out. The conclusions are:(1) Stress of frame 9 is more sensitive to initial imperfection than circumferential stress of toroidmidsurface,which is a new concern;(2) To strength the frames in the sides of toroid not only can decrease the stress of frame,but also can reduce the circumference stress of toroid's midsurface.展开更多
基金National Natural Science Foundation of China Under Grant No.50678021
文摘In this paper, the cone model is applied to the vibration analysis of two foundations on a layered soil half space. In the analysis, the total stress field in the subsoil is divided into the free-field and the scattering field. Seed＇s simplified method is adopted for the free-field analysis, while the cone model is proposed for analyzing the dynamic scattering stress wave field. The shear stress field and the compressive stress field in the layered stratum with two scattering sources are calculated by shear cone and compressive cone, respectively. Furthermore, the stress fields in the subsoil with two foundations are divided into six zones, and the P wave and S wave are analyzed in each zone. Numerical results are provided to illustrate features of the added stress field for two surface foundations under vertical and horizontal sinusoidal force excitation. The proposed cone model may be useful in handling some of the complex problems associated with multi-scattering sources.
基金This study was supported by National Natural Science Foundation(81371345).
文摘Objective:To investigate the effects of minimally invasive craniotomy combined with edaravone on cerebral oxygen metabolism, cerebrovascular function and oxidative stress in patients with acute cerebral hemorrhage.Methods:A total of 100 patients with acute cerebral hemorrhage treated in our hospital from March 2015 to February 2017 were randomly divided into control group and observation group. 50 patients in the control group were treated with minimally invasive craniotomy. On the basis of control group, patients in the observation group were treated with edaravone. Cerebral oxygen metabolism, cerebrovascular function and oxidative stress were measured later in both groups.Results:After treatment, the levels of SOD in both groups increased significantly and MDA levels decreased significantly, and SOD level in the observation group was (97.34±1.95) U/mL, which was significantly higher than the control group, MDA level was (2.77±0.11) mol/L and significantly lower than that of the control group after treatment;After treatment, the levels of ET in both groups were significantly lower than those before treatment, and the levels of CGRP were significantly higher than those before treatment. ET level in observation group was (3.24±0.22) μg/L after treatment, which was significantly lower than that in control group (59.67±0.79) pg/mL, which was significantly higher than the control group;After treatment, the levels of SjvO2, CjvO2 and PbtO2 in both groups were significantly increased compared with before treatment, the levels of Da-jvO2 and CEO2 were significantly lower than the level of before treatment, and the levels of SjvO2, The levels of CjvO2 and PbtO2 were (62.93±1.63)%, (99.31±0.94) mL/L and (28.56±1.55) mmHg, which were significantly higher than the control group. Da-jvO2 and CEO2 levels were (51.31±1.13) mL/L and (30.52±0.43)%, which were significantly lower than the control group.Conclusion: Edaravone combined with minimally invasive craniotomy can effectively reduce the level of oxidative stress, improve endothelial function and cerebral oxygen metabolism, and has reliable curative effect. It is worth further clinical application.
文摘As a new joint structure,the impact of initial imperfection to stress of Concave cone-toroid-cylinder combined shell was analyzed. Firstly the location and shape of combined shell's initial imperfection caused by welding was studied. Secondly dominated stress was chosen after comparing varioustypical stress. Then it was analyzed that the influence of imperfection to dominated stress via changing the shape of frame's deflection and shell's concave-convex. At last the strengthening case for combined shell with imperfection was pointed out. The conclusions are:(1) Stress of frame 9 is more sensitive to initial imperfection than circumferential stress of toroidmidsurface,which is a new concern;(2) To strength the frames in the sides of toroid not only can decrease the stress of frame,but also can reduce the circumference stress of toroid's midsurface.
