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An elastic–slip interface model is proposed to investigate the effective elastic modulus of elliptical-fiber reinforced asphalt concrete, and the nonlinear factor related with the second-order term of strain is used to consider the large deformation of asphalt concrete. The representative volume element with effective isotropic medium is introduced to describe the overall properties of elliptical-fiber reinforced asphalt concrete. Combining the conformal mapping technique and polynomial function expanded method, a closed form solution of effective elastic modulus is obtained. Through numerical examples, the effects of interface material coefficients and the nonlinear factor on the effective elastic modulus under different shapes of fibers are discussed in detail. To validate the present interface model, experimental investigation on the interface effect on the elastic modulus is presented.

Obtaining effective value points is one of key issues in cubic B-spline curve reconstruction. Since it is unfavorable for the selection of value points through curvature methods and the point cloud data acquired from ICT slice images is characterized with large volume of data, high noise and density, a baseline adaptive method is presented to get value points for curve reconstruction, baseline and scale threshold determined by wavelet multi-scale, in which the value points is obtained and curve is reconstructed automatically. Hausdorff distance is adopted to calculate the error of cubic B-spline curve reconstruction. Comparative analysis with existing methods proves that our method can effectively restrain noise and quickly reconstruct contour curves.

How to effectively extract contour dominant points is one of key problems in process of industrial CT image, second extraction method was put forward. Second extraction method included two steps: rough extraction and accurate extraction. Firstly, discrete circular curvatures of contour points are calculated. Secondly, through rough extraction step, bad points and points which arent correlated with contour features were removed. At last, through accurate extraction step, contour dominant points were extracted by levels of detail. Experimental results show that contour dominant points can describe contours shape and redundant data are removed, the proposed method is simple and efficient.

Through considering the symmetry constraint characteristics in mechanical product contours, an auto-identification method of two-dimensional symmetrical contour based on feature matching is presented in this paper. Firstly, the feature points are extracted based on contour cloud point data partition and by using offset method, the different distribution rules of axis-symmetrical and rotation-symmetrical images for judging the type of symmetry was studied. The feature description parameters of symmetrical contour were calculated by adopting rotational inertia method and periodic method, which is regarded as the parameters for solving overall constraint optimization of the contour. Examples show that the proposed method can effectively identify the symmetrical contours and their types, and accurately extract the symmetrical constraint features.

Position-limit protection equipment is the major control equipment on CNC machine, whose logic control method is the assurance of normal work of position-limit protection equipments. It will reduce the effect of position-limit protection or cause it malfunction, if we apply the logical control method not suitably. Current CNC machines are provided with a positive control limitation protection device, and then it is likely to happen malfunction even cause accidents due to its electric circuit errors or its open circuit. In order to solve this shortcoming, somebody has worked out a new method, which is called negative logic control. This paper introduces the new logic control method’s basic principle and its practical usage.

The spring-mass-capacitor structure in micro-electro-mechanical systems (MEMS) is a typical macromodel, its response and stability under step voltage is presented in this paper. Energy method is used to analyze the dynamic behavior of mass block where its velocity is zero and accelerometer is zero, respectively. The condition of stability under step voltage is the initial stiffness ratio must less than 0.25, and finally the relation of energy loss and oscillating behavior of block is analyzed. The conclusion is useful to analyze the response of structure and helpful to design a MEMS system composing of spring-mass-capacitor structure.

To detect the change of p38 protein expression and investigate the relationship of p38 and lymph nodes metastasis in human breast carcinomas. Sixty breast cancer cases were checked by S-P immunohistochemistry technique and 30 breast cancer cases were examined by Western Blot. Immunohistochemical results showed that p38 protein was observed in breast cancer and normal cytoplasm. P-p38 was positive in nucleus in breast cancer. P38 protein expressed positively in 29 out of 38 patients who had lymph nodes metastasis (positive rate 76.3%) and in 9 out of 22 patients who had no lymph nodes metastasis (positive rate 40.9%). There was a significant difference between these two groups (P 0.05). p38 and p-p38 protein expressions had relationship with lymph nodes metastasis and the levels of p38 and p-p38 protein expression in groups with lymph nodes metastasis were higher than in groups without lymph nodes metastasis. P38 and p-p38 protein expressions had relationship with clinical grades and had no relationship with patients’ age and tumor size.

Objective: To investigate the expression of ERK and p-ERK protein in human breast cancer and their corresponding tissue, to assess the significance of ERK signal pathway in tumorigenesis and progression of breast carcinoma. Methods: 40 breast cancer cases were used in S-P immunohistochemistry technique and Western Blot study. Results: The expression of ERK1, ERK2, and p- ERK protein levels increased remarkably in breast cancer tissues in comparison to normal tissues (P

Intensity inhomogeneity often causes considerable difficulties in image segmentation. In order to tackle this problem, we propose a novel region-based active contour model in a variational level set formulation. We first define a data fitting energy with a local Gaussian distribution fitting (LGDF) term, which induces a local force to attract the contour and stops it at object boundaries, and a local signed difference (LSD) term based on local entropy, which possesses both local separability and global consistency. This energy is then incorporated into a level set formulation with a level set regularization term that is necessary for accurate computation in the corresponding level set method. Experimental results show that the proposed model can not only segment images with intensity inhomogeneities and weak boundaries but also be robust to the noise, initial contours.

We sought to explore the pulmonary haemodynamic changes in rheumatic mitral stenosis patients with secondary pulmonary hypertension. The pulmonary artery resistance and compliance of 35 patients with rheumatic mitral stenosis and 12 controls without cardiopulmonary vascular disease were evaluated by using an improved method, which is based on making calculations with parameters obtained from right heart catheterisation. The results are as follows: (1) pulmonary artery compliance in patients with secondary pulmonary hypertension was significantly lower than that of the control group (P0.01); (2) linear correlation analyses showed that preoperative mean pulmonary artery pressure (mPAP) closely correlated with zero-pressure compliance in the mitral stenosis group (r=-0.745, P0.05); (3) PAP and pulmonary vascular resistance decreased significantly in both groups with mitral stenosis after infusing 0.5 μg kg(-1) min(-1) of sodium nitroprusside (P0.01). The pulmonary zero pressure compliance and mean pressure compliance increased significantly in the group with mild pulmonary hypertension; whereas in the severe group, the mean compliance changed with significance as the mPAP decreased (1.51 ± 0.59 vs 1.81 ± 0.77 ml/mmHg), however no significant change occurred in the pulmonary zero pressure compliance (2.35 ± 1.24 ml/mmHg vs. 2.24 ± 1.53 ml/mmHg, P0.05) The walls of pulmonary artery vessels in patients with pulmonary hypertension secondary to rheumatic mitral stenosis appeared to be remodelled by varying degrees as indicated by their haemodynamic properties. Structural remodelling may be a factor affecting preoperative pulmonary artery pressure. Mitral stenosis patients with severe pulmonary hypertension have significantly lower responses to sodium nitroprusside possibly due to aggradation and deposition of collagen in the artery walls, decreasing constriction and dilation, or atrophy of smooth muscle cells.