Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated nu...Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated numerically by software Fluent, and its dynamic characteristics were analyzed during the work process such as raising leg, loading and overflow, the influence of the related parameters on high-flow water three-way valve was determined. The results as follows: during the raising leg stage and early raising leg stage, when the damping ratio increases, the overshoot of system decreases and the setting time reduces, and the dynamic response performance has a significant improvement. During the loading stage and the overflow stage, the pressure in plunger chamber of single hydraulic prop, the output flow and the displacement of the high-flow water three-way valve decrease with the decreasing of the external load. The spring stiffness of the safety valve directs the flow and the spool's displacement of the safety valve, and it can be used to control the high-flow three-way valve's sensitivity.展开更多
Objective: To investigate the correlations of vascular endothelial growth factor (VEGF)-positive tumor angiogenesis and the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogeni...Objective: To investigate the correlations of vascular endothelial growth factor (VEGF)-positive tumor angiogenesis and the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma. Methods: 30 patients with VEGF-positive bronchogenic adenocarcinomas (diameter ≤ 4 cm) underwent multi-location dynamic contrast material-enhanced (nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/sec by using an autoinjector) serial CT. The quantifiable parameters (Perfusion, peak height, ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta and mean transit time) of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma were compared with microvessel densities (MVDs) and VEGF expression by immunohistochemistry. Results: Peak height of VEGF-positive bronchogenic adenocarcinoma was 36.06 HU ± 13.57 HU, bronchogenic adenocarcinoma-to-aorta ratio 14.25% ± 4.92, and perfusion value 29.66 ± 5.60 mL/min/100 g , mean transit time 14.86 s ± 5.84 s, and MVD 70.15 ± 20.03. Each of peak height, ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta and perfusion correlated positively with MVD (r = 0.781, P < 0.0001; r = 0.688, P < 0.0001; r = 0.716, P < 0.0001; respectively). No significant correlation was found between mean transit time and MVD (r = 0.260, P = 0.200 > 0.05). Conclusion: Perfusion, peak height and ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta reflect MVD in VEGF-positive bronchogenic adenocarcinoma. Perfusion, peak height and ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta derived with dynamic CT might be index for VEGF-related tumor angiogenesis in bronchogenic adenocarcinoma.展开更多
Tensor representation is useful to reduce the overfitting problem in vector-based learning algorithm in pattern recognition.This is mainly because the structure information of objects in pattern analysis is a reasonab...Tensor representation is useful to reduce the overfitting problem in vector-based learning algorithm in pattern recognition.This is mainly because the structure information of objects in pattern analysis is a reasonable constraint to reduce the number of unknown parameters used to model a classifier.In this paper, we generalize the vector-based learning algorithm TWin Support Vector Machine(TWSVM) to the tensor-based method TWin Support Tensor Machines(TWSTM), which accepts general tensors as input.To examine the effectiveness of TWSTM, we implement the TWSTM method for Microcalcification Clusters(MCs) detection.In the tensor subspace domain, the MCs detection procedure is formulated as a supervised learning and classification problem, and TWSTM is used as a classifier to make decision for the presence of MCs or not.A large number of experiments were carried out to evaluate and compare the performance of the proposed MCs detection algorithm.By comparison with TWSVM, the tensor version reduces the overfitting problem.展开更多
Currently in China, to study the replacement rate of pension reform in public institutions and to find out the key problems, which is of practical significance for the reform of the pension insurance system. In this p...Currently in China, to study the replacement rate of pension reform in public institutions and to find out the key problems, which is of practical significance for the reform of the pension insurance system. In this paper, the impact of pension income and expenditure patterns on the substitution rate is analyzed, and the factors that affect the level of substitution rate are analyzed, and the corresponding policy recommendations are put forward.展开更多
The paper shows that, for a unit circular plate, Reissner-Mindlin plate model with hard simply support does not capture the boundary layer behaviour for the bending moment when the load is independent of θ, where (r,...The paper shows that, for a unit circular plate, Reissner-Mindlin plate model with hard simply support does not capture the boundary layer behaviour for the bending moment when the load is independent of θ, where (r,θ) is the polar coordinates in plane. In contrast p-model shows this boundary layer, which is proved theoretically and numerically. But for the case when the boundary is a straight line, the boundary layer for p-model is weak and disappears as the plate thickness tends to zero.展开更多
Recently, the LHCb collaboration reported the first evidence for the decay B08 →μ+μ-. A branching ratio of (B08 →μ+μ-) = (3.2+1.5-1.2) x 10-9 is given. Using the newest data, and together with the most pr...Recently, the LHCb collaboration reported the first evidence for the decay B08 →μ+μ-. A branching ratio of (B08 →μ+μ-) = (3.2+1.5-1.2) x 10-9 is given. Using the newest data, and together with the most precise predictions of the Standard Model contributions to the decay, we derive the constraints on the combinations of the R-parity violating parameters. Our results are several orders of magnitudes stronger than the constraints in the previous literature. We also update the constraints on the relevant parameters using the upper limit of B(B08 →μ+μ-).展开更多
基金Supported by the National Natural Science Foundation of China (51075001) the Nature Science Research Project of Anhui Province (KJ2009A020)
文摘Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated numerically by software Fluent, and its dynamic characteristics were analyzed during the work process such as raising leg, loading and overflow, the influence of the related parameters on high-flow water three-way valve was determined. The results as follows: during the raising leg stage and early raising leg stage, when the damping ratio increases, the overshoot of system decreases and the setting time reduces, and the dynamic response performance has a significant improvement. During the loading stage and the overflow stage, the pressure in plunger chamber of single hydraulic prop, the output flow and the displacement of the high-flow water three-way valve decrease with the decreasing of the external load. The spring stiffness of the safety valve directs the flow and the spool's displacement of the safety valve, and it can be used to control the high-flow three-way valve's sensitivity.
文摘Objective: To investigate the correlations of vascular endothelial growth factor (VEGF)-positive tumor angiogenesis and the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma. Methods: 30 patients with VEGF-positive bronchogenic adenocarcinomas (diameter ≤ 4 cm) underwent multi-location dynamic contrast material-enhanced (nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/sec by using an autoinjector) serial CT. The quantifiable parameters (Perfusion, peak height, ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta and mean transit time) of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma were compared with microvessel densities (MVDs) and VEGF expression by immunohistochemistry. Results: Peak height of VEGF-positive bronchogenic adenocarcinoma was 36.06 HU ± 13.57 HU, bronchogenic adenocarcinoma-to-aorta ratio 14.25% ± 4.92, and perfusion value 29.66 ± 5.60 mL/min/100 g , mean transit time 14.86 s ± 5.84 s, and MVD 70.15 ± 20.03. Each of peak height, ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta and perfusion correlated positively with MVD (r = 0.781, P < 0.0001; r = 0.688, P < 0.0001; r = 0.716, P < 0.0001; respectively). No significant correlation was found between mean transit time and MVD (r = 0.260, P = 0.200 > 0.05). Conclusion: Perfusion, peak height and ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta reflect MVD in VEGF-positive bronchogenic adenocarcinoma. Perfusion, peak height and ratio of peak height of the bronchogenic adenocarcinoma to that of the aorta derived with dynamic CT might be index for VEGF-related tumor angiogenesis in bronchogenic adenocarcinoma.
基金Supported by the National Natural Science Foundation of China (No. 60771068)the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2007F248)
文摘Tensor representation is useful to reduce the overfitting problem in vector-based learning algorithm in pattern recognition.This is mainly because the structure information of objects in pattern analysis is a reasonable constraint to reduce the number of unknown parameters used to model a classifier.In this paper, we generalize the vector-based learning algorithm TWin Support Vector Machine(TWSVM) to the tensor-based method TWin Support Tensor Machines(TWSTM), which accepts general tensors as input.To examine the effectiveness of TWSTM, we implement the TWSTM method for Microcalcification Clusters(MCs) detection.In the tensor subspace domain, the MCs detection procedure is formulated as a supervised learning and classification problem, and TWSTM is used as a classifier to make decision for the presence of MCs or not.A large number of experiments were carried out to evaluate and compare the performance of the proposed MCs detection algorithm.By comparison with TWSVM, the tensor version reduces the overfitting problem.
文摘Currently in China, to study the replacement rate of pension reform in public institutions and to find out the key problems, which is of practical significance for the reform of the pension insurance system. In this paper, the impact of pension income and expenditure patterns on the substitution rate is analyzed, and the factors that affect the level of substitution rate are analyzed, and the corresponding policy recommendations are put forward.
文摘The paper shows that, for a unit circular plate, Reissner-Mindlin plate model with hard simply support does not capture the boundary layer behaviour for the bending moment when the load is independent of θ, where (r,θ) is the polar coordinates in plane. In contrast p-model shows this boundary layer, which is proved theoretically and numerically. But for the case when the boundary is a straight line, the boundary layer for p-model is weak and disappears as the plate thickness tends to zero.
基金Supported by the National Science Foundation of China under the Grant Nos, 11075168, 11228512, and 11235005, and the National Science Council of Taiwan under Grant No. 101-2811-M-001-060
文摘Recently, the LHCb collaboration reported the first evidence for the decay B08 →μ+μ-. A branching ratio of (B08 →μ+μ-) = (3.2+1.5-1.2) x 10-9 is given. Using the newest data, and together with the most precise predictions of the Standard Model contributions to the decay, we derive the constraints on the combinations of the R-parity violating parameters. Our results are several orders of magnitudes stronger than the constraints in the previous literature. We also update the constraints on the relevant parameters using the upper limit of B(B08 →μ+μ-).