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No thermodynamic description was performed for the Co-Mg binary system according to literature review. Consequently, this binary system has been investigated by means of CALPHAD (CALculation of PHAse Diagrams) approach in the present work. The experimental phase diagram and thermodynamic data available in the literature were critically assessed. Based on the reliable literature data, a new set of self-consistent thermodynamic parameters for the Co-Mg system is obtained. The calculated results agree well with the experimental data from the literature, indicating the reasonability of the present thermodynamic optimization.

This study was a prospective single arm trial conducted in Zhejiang Jinhua Guangfu hospital from February 2018 to June 2020. A total of 39 patients (32 males and 7 females) with esophageal cancer, aged from 44 to 82 (69±9) years were enrolled. Diffusion weighted magnetic resonance imaging(MR-DWI) was implemented to evaluate the changes of apparent diffusion coefficient(ADC) value before and after chemoradiotherapy. The results showed that the ADC value after chemoradiotherapy was higher than that before treatment[(2.03±0.42)×10⁻³ mm本研究采用前瞻性单臂试验的方法，选择自2018年2月至2020年6月在浙江金华广福医院接受放化疗的39例食管癌患者，男32例，女7例，年龄44~82（69±9）岁。用磁共振扩散加权成像（MR-DWI）检测患者治疗前后表观弥散系数（ADC）变化。结果显示治疗后ADC值较治疗前显著性升高［（2.03±0.42）×10⁻³ mm

The fabrication of individualized hip prosthesis stem requires high machining freedom to dovetail precisely with the bond cavity of the patient. Hence, a 3-axial linkage motion is proposed in 4-axial milling along with a 1-axial differential drive and a cutter offset angle. Its advantage is to prevent from the accumulated errors of multi-axial motions. First, the centerline of spatial stem with the length of 200 mm was installed to a rotating axis; then, the transfer model of non-closed polar coordinate points was constructed to design 2D closed tool paths for the control of 3D cutting contact points; finally, the form error and the surface roughness of milled stem surface were investigated in connection with cutter posture angle. Theoretical analysis shows that the cutter offset angle contributes to an increase in cutter posture angle for high cutting velocity and the predication of the interference between cutter bar and workpiece. Experimental results show that the milled surface roughness and the milled form error are decreased by about 50 % and reach 0.26 and 126 μm when the cutter posture angle decreases to 20–40 °, respectively. It is confirmed that the 3-axial linkage milling along with 1-axial differential drive is likely to realize the precision machining of spatial hip prosthesis stem by controlling the cutter offset angle.

A stochastic variational principle (SVP) is presented in this paper. Based on the SVP, the stochastic finite segment method (SFSM) is developed for and applied to the analysis of shear-lag effect on a box-girder. The random property of physical and/or geometrical parameters is incorporated consistently into the total potential energy functional of the box-girder. Then the second-order perturbation techniques are employed to develop a set of expanded deterministic expressions of the functional. It is shown that the second-order functional is necessary and sufficient to derive all the governing equations. Then the recursive stiffness equations of the SFSM are obtained by the stationary conditions of the second-order energy functional. The stochastic shear-lag effect on the box-girder is evaluated by means of the SFSM. An example is given to demonstrate the efficiency and accuracy of the present method. Results are compared with the analytical variational solutions and those achieved by the technique of direct Monte Carlo simulation and the finite strip method, respectively, showing desirable agreement.

This paper presents a quadratic finite element with generalized degrees of freedom (GDOF) and a quadratic finite strip with GDOF based on the principle that the local displacement fields of elements should be compatible with the global displacement field of the corresponding systems. Firstly, a global displacement field is developed using quadratic B-spline functions. Secondly, local displacement fields of elements and strips are constructed, employing multi-term interpolation polynomials of second degree. Making the local displacement fields of elements and strips be compatible with their corresponding global displacement fields, respectively, models of the finite element with GDOF and the finite strip with GDOF are accordingly generated. On the other hand, the quadratic B-spline function is convenient to derive the explicit form of characteristic equations for computing model because of its lower order, and accordingly simplifies the computation, compared with cubic and quintic spline functions. Several numerical examples demonstrate the accuracy, simplicity and versatility of the present element and strip in the analysis of thin-walled structures.

The integrated optimum problem of structures subjected to strong earthquakes and wind excitations, optimizing the number of actuators, the configuration of actuators and the control algorithms simultaneously, is studied. Two control algorithms, optimal control and acceleration feedback control, are used as the control algorithms. A multi-level optimization model is proposed with respect to the solution procedure of the optimum problem. The characteristics of the model are analysed, and the formulation of each suboptimization problem at each level is presented. To solve the multi-level optimization problem, a multi-level genetic algorithm (MLGA) is proposed. The proposed model and MLGA are used to solve two multi-level optimization problems in which the optimization of the number of actuators, the positions of actuators and the control algorithm are considered in different levels. In problem 1, an example structure is excited by strong wind, and in problem 2, an example structure is subjected to strong earthquake excitation. Copyright © 2001 John Wiley & Sons, Ltd.