This paper presents an optical sensor technique used in the damage evaluation which is formed by structurally integrated fiber optic reticulate sensors embedded in the composite materials. The fibers are processed by ...This paper presents an optical sensor technique used in the damage evaluation which is formed by structurally integrated fiber optic reticulate sensors embedded in the composite materials. The fibers are processed by chemical method and their outsides are peeled to form particles of irregular distribution and they differ in size, so the slight disturbance range of stochastic wall are formed in fibers. According to the characteristics of power loss of waveguide mode caused by slight disturbance of stochastic wall and radiative mode transmission, the range of slight disturbance of stochastic wall may be served as the sensitive range of the sensor. On the basis of theory of slight disturbance of stochastic wall of planar optical waveguide, the relation between the corrosion time and the opposite power loss by experiments is investigated. In this paper, the measurement results of object of SIFORS are also presented. The results show that the optical sensor technique may be used in the damage evaluation of an aircraft.展开更多
AIM: To evaluate the feasibility, safety and efficacy of ultrasound-guided microwave (MW) ablation for abdominal wall metastatic tumors. METHODS: From August 2007 to December 2010, a total of 11 patients with 23 abdom...AIM: To evaluate the feasibility, safety and efficacy of ultrasound-guided microwave (MW) ablation for abdominal wall metastatic tumors. METHODS: From August 2007 to December 2010, a total of 11 patients with 23 abdominal wall nodules (diameter 2.59 cm ± 1.11 cm, range 1.3 cm to 5.0 cm) were treated with MW ablation. One antenna was inserted into the center of tumors less than 1.7 cm, and multiple antennae were inserted simultaneously into tumors 1.7 cm or larger. A 21 gauge thermocouple was inserted near important organs which required protection (such as bowel or gallbladder) for real-time temperature monitoring during MW ablation. Treatment outcome was observed by contrast-enhanced ultrasound and magnetic resonance imaging (MRI) [or computed tomography (CT)] during follow-up. RESULTS: MW ablation was well tolerated by all patients. Six patients with 11 nodules had 1 thermocouple inserted near important organs for real-time temperature monitoring and the maximum temperature was 56 ℃. Major complications included mild pain (54.5%), post-ablation fever (100%) and abdominal wall edema (25%). All 23 tumors (100%) in this group were completely ablated, and no residual tumor or local recurrence was observed at a median follow-up of 13 mo (range 1 to 32 mo). The ablation zone was well defined on contrast-enhanced imaging (contrast-enhanced CT, MRI and/or contrast-enhanced ultrasound) and gradually shrank with time. CONCLUSION: Ultrasound-guided MW ablation may be a feasible, safe and effective treatment for abdominal wall metastatic tumors in selected patients.展开更多
Turbulent penetration can occur when hot and cold fluids mix in a horizontal T-junction pipe at nuclear plants. Caused by the unstable turbulent penetration, temperature fluctuations with large amplitude and high freq...Turbulent penetration can occur when hot and cold fluids mix in a horizontal T-junction pipe at nuclear plants. Caused by the unstable turbulent penetration, temperature fluctuations with large amplitude and high frequency can lead to time-varying wall thermal stress and even thermal fatigue on the inner wall. Numerous cases, however, exist where inner wall temperatures cannot be measured and only outer wall temperature measurements are feasible. Therefore, it is one of the popular research areas in nuclear science and engineering to estimate temperature fluctuations on the inner wall from measurements of outer wall temperatures without damaging the structure of the pipe. In this study, both the one-dimensional(1D) and the two-dimensional(2D) inverse heat conduction problem(IHCP) were solved to estimate the temperature fluctuations on the inner wall. First, numerical models of both the 1D and the 2D direct heat conduction problem(DHCP) were structured in MATLAB, based on the finite difference method with an implicit scheme. Second, both the 1D IHCP and the 2D IHCP were solved by the steepest descent method(SDM), and the DHCP results of temperatures on the outer wall were used to estimate the temperature fluctuations on the inner wall. Third, we compared the temperature fluctuations on the inner wall estimated by the 1D IHCP with those estimated by the 2D IHCP in four cases:(1) when the maximum disturbance of temperature of fluid inside the pipe was 3℃,(2) when the maximum disturbance of temperature of fluid inside the pipe was 30℃,(3) when the maximum disturbance of temperature of fluid inside the pipe was 160℃, and(4) when the fluid temperatures inside the pipe were random from 50℃ to 210℃.展开更多
文摘This paper presents an optical sensor technique used in the damage evaluation which is formed by structurally integrated fiber optic reticulate sensors embedded in the composite materials. The fibers are processed by chemical method and their outsides are peeled to form particles of irregular distribution and they differ in size, so the slight disturbance range of stochastic wall are formed in fibers. According to the characteristics of power loss of waveguide mode caused by slight disturbance of stochastic wall and radiative mode transmission, the range of slight disturbance of stochastic wall may be served as the sensitive range of the sensor. On the basis of theory of slight disturbance of stochastic wall of planar optical waveguide, the relation between the corrosion time and the opposite power loss by experiments is investigated. In this paper, the measurement results of object of SIFORS are also presented. The results show that the optical sensor technique may be used in the damage evaluation of an aircraft.
文摘AIM: To evaluate the feasibility, safety and efficacy of ultrasound-guided microwave (MW) ablation for abdominal wall metastatic tumors. METHODS: From August 2007 to December 2010, a total of 11 patients with 23 abdominal wall nodules (diameter 2.59 cm ± 1.11 cm, range 1.3 cm to 5.0 cm) were treated with MW ablation. One antenna was inserted into the center of tumors less than 1.7 cm, and multiple antennae were inserted simultaneously into tumors 1.7 cm or larger. A 21 gauge thermocouple was inserted near important organs which required protection (such as bowel or gallbladder) for real-time temperature monitoring during MW ablation. Treatment outcome was observed by contrast-enhanced ultrasound and magnetic resonance imaging (MRI) [or computed tomography (CT)] during follow-up. RESULTS: MW ablation was well tolerated by all patients. Six patients with 11 nodules had 1 thermocouple inserted near important organs for real-time temperature monitoring and the maximum temperature was 56 ℃. Major complications included mild pain (54.5%), post-ablation fever (100%) and abdominal wall edema (25%). All 23 tumors (100%) in this group were completely ablated, and no residual tumor or local recurrence was observed at a median follow-up of 13 mo (range 1 to 32 mo). The ablation zone was well defined on contrast-enhanced imaging (contrast-enhanced CT, MRI and/or contrast-enhanced ultrasound) and gradually shrank with time. CONCLUSION: Ultrasound-guided MW ablation may be a feasible, safe and effective treatment for abdominal wall metastatic tumors in selected patients.
基金supported by the National Natural Science Foundation of China(Project No.51276009)Program for New Century Excellent Talents in University(No.NCET-13-0651)
文摘Turbulent penetration can occur when hot and cold fluids mix in a horizontal T-junction pipe at nuclear plants. Caused by the unstable turbulent penetration, temperature fluctuations with large amplitude and high frequency can lead to time-varying wall thermal stress and even thermal fatigue on the inner wall. Numerous cases, however, exist where inner wall temperatures cannot be measured and only outer wall temperature measurements are feasible. Therefore, it is one of the popular research areas in nuclear science and engineering to estimate temperature fluctuations on the inner wall from measurements of outer wall temperatures without damaging the structure of the pipe. In this study, both the one-dimensional(1D) and the two-dimensional(2D) inverse heat conduction problem(IHCP) were solved to estimate the temperature fluctuations on the inner wall. First, numerical models of both the 1D and the 2D direct heat conduction problem(DHCP) were structured in MATLAB, based on the finite difference method with an implicit scheme. Second, both the 1D IHCP and the 2D IHCP were solved by the steepest descent method(SDM), and the DHCP results of temperatures on the outer wall were used to estimate the temperature fluctuations on the inner wall. Third, we compared the temperature fluctuations on the inner wall estimated by the 1D IHCP with those estimated by the 2D IHCP in four cases:(1) when the maximum disturbance of temperature of fluid inside the pipe was 3℃,(2) when the maximum disturbance of temperature of fluid inside the pipe was 30℃,(3) when the maximum disturbance of temperature of fluid inside the pipe was 160℃, and(4) when the fluid temperatures inside the pipe were random from 50℃ to 210℃.
