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Rotational speed and load-carrying capacity are two mutual coupling factors which affect high precision and stable operation of a hydrostatic thrust bearing. The purpose of this paper is to study reasonable matching relationship between the rotational speed and the load-carrying capacity.

A mathematical model of relationship between the rotational speed and the load-carrying capacity of the hydrostatic bearing with double-rectangle recess is set up on the basis of the tribology theory and the lubrication theory, and the load and rotational speed characteristics of an oil film temperature field and a pressure field in the hydrostatic bearing are analyzed, reasonable matching relationship between the rotational speed and the load-carrying capacity is deduced and a verification experiment is conducted.

By increasing the rotational speed, the oil film temperature increases, the average pressure decreases and the load-carrying capacity decreases. By increasing the load-carrying capacity, the oil film temperature and the average pressure increases and the rotational speed decreases; corresponding certain reasonable matching values are available.

The load-carrying capacity can be increased and the rotational speed improved by means of reducing the friction area of the oil recess by using low-viscosity lubricating oil and adding more oil film clearance; but, the stiffness of the hydrostatic bearing decreases.

This paper aims to present a simplified solution method for the elasto-plastic consolidation problem under different stress paths.

First, a double-yield-surface model is introduced as the constitutive model framework, and a partial derivative coefficient sequence is obtained by using numerical approximation using Gauss nuclear function to construct a discretization constitutive model which can reflect the influence of different stress paths. Then, the model is introduced to Biot’s consolidation theory. Volumetric strain of each step as the right-hand term, the continuity equation is simplified as a Poisson equation and the fundamental solution is derived by the variable separation method. Based on it, a semi-analytical and semi-numerical method is presented and implemented in a finite element program.

The method is a simplified solution that is more convenient than traditional coupling stiffness matrix method. Moreover, the consolidation of the semi-infinite foundation model is analyzed. It is shown that the numerical method is sufficiently stable and can reflect the influence of stress path, loading distribution width and some other factors on the deformation of soil skeleton and pore water pressure.

Original features of this research include semi-numerical semi-analytical consolidation method; pore water pressure and settlements of different stress paths are different; maximum surface uplift at 3.5a; and stress path is the main influence factor for settlement when loading width a > 10 m.

The purpose of this paper is to efficiently use as few sample points as possible to get a sufficiently explored design space and an accurate optimum for adaptive metamodel-based design optimization (AMBDO).

A parameterized lower confidence bounding (PLCB) scheme is proposed in which a cooling strategy is introduced to guarantee the balance between exploitation and exploration by varying weights of the predicting error and optimum of a metamodel. The proposed scheme is investigated by a set of test functions and a structural optimization problem, in which PLCB with four kinds of cooling control functions are studied. Moreover, other infill criteria (such as expected improvement and its extension versions) are taken into comparison.

Results show that the proposed PLCB (especially PLCB with the first cooling control function) based AMBDO method can find the optimum with fewer evaluations and maintain good accuracy, which means the proposed PLCB contributes to the excellent efficiency and accuracy in finding global optimal solutions.

The parameterized version of the lower confidence bound metric is proposed for AMBDO, typically used in the context of adaptive sampling in efficient global optimization.

The purpose of the study reported in this paper is to synthesis curcumin, which was reported to possess broad pharmacological effects and excellent dyeing properties, via Claisen-Schmidt condensation reaction catalysed by an efficient and green solid base catalyst, KF/Al₂O₃.

A series of catalysts with different KF loadings and varying calcination temperatures had been prepared, characterised by Brunauer–Emmett–Taller surface area, temperature-programmed desorption with CO₂ using infrared spectroscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy, and tested in the Claisen–Schmidt condensation reaction. The effects of different reaction parameters such as temperature, the amount of catalyst, reactant ratio and time on the synthesis of curcumin were examined. The possibility of recycling the catalyst was also investigated in detail. Moreover, the reaction mechanism and the role of KF/Al₂O₃ in the synthetic process were discussed.

The study provides an efficient and green solid base catalyst, KF/Al₂O₃, and 64.3 per cent yield of curcumin was obtained under the optimum reaction conditions. Experimental results indicate that the third reused catalyst could retain part of the catalytic activity, and the regenerated one could be reused with reasonable catalytic activity. Besides, K₃AlF₆ was proposed as the active site of the catalyst for the reaction by the analysis of the characterization results of KF/Al₂O₃.

KF/Al₂O₃ was found to be an efficient catalyst for catalytic synthesis of curcumin and could be easily recycled several times. This information may be useful for further research and practical applications of curcumin.

This paper aims to effectively achieve endmembers and relative abundances simultaneously in hyperspectral image unmixing yield. Hyperspectral unmixing, which is an important step before image classification and recognition, is a challenging issue because of the limited resolution of image sensors and the complex diversity of nature. Unmixing can be performed using different methods, such as blind source separation and semi-supervised spectral unmixing. However, these methods have disadvantages such as inaccurate results or the need for the spectral library to be known a priori.

This paper proposes a novel method for hyperspectral unmixing called fuzzy c-means unmixing, which achieves endmembers and relative abundance through repeated iteration analysis at the same time.

Experimental results demonstrate that the proposed method can effectively implement hyperspectral unmixing with high accuracy.

The proposed method present an effective framework for the challenging field of hyperspectral image unmixing.

The purpose of this paper is to investigate the long-term differences in household income and their causes in the people’s commune through a panel of micro-data.

The income mobility method (including static Gini mobility and dynamic income transition matrix) as well as the multinomial logit model) are employed in this paper.

Empirical results indicate that differences in household income were relatively low during the people’s commune period. In addition, both Gini mobility and income transition matrix analyses show that income mobility in the long term was faster than that in the short term, suggesting income mobility was beneficial for low-income earners in the long term, i.e., there was an pro-poorness. The major factor influencing household income was the structure of family population, not the quantity of labor input.

This paper is the first using income mobility method to study farmers’ income disparity and conducting factor decomposition on it in the people’s commune period. The micro-data on production team level applied in the paper is of high value, and the paper is helpful to understand the low efficiency of the people’s commune.

College graduates' unemployment problems have gradually become a social problem. This paper aims to find out whether entrepreneurship education can promote employment and improve job satisfaction by finding the impact of entrepreneurship education on increasing employment performance.

The paper surveys the undergraduates who graduated by 2010 from Jilin University and attained their entrepreneurship and employment performance value. The paper draws a conclusion by making correlation analysis.

The results showed that entrepreneurship has a positive impact effect on the employment performance. It is confirmed entrepreneurship education has a positive effect on employment.

The paper made a link between the entrepreneurship research and the employment study, and provided a theoretical underpinning to the concept of “Encouraging entrepreneurship to drive employment”. This also provided the rationality and necessity of entrepreneurship education.

The purpose of this paper is to design and develop 14-degree of freedom (DOF) robotic micromanipulator with which LIGA devices and axle hole part can be both manipulated and assembled.

The in-house robotic microassembly system is composed of a 6-DOF large motion serial robot with microgrippers, a hexapod six-DOF precision alignment worktable and a vision system whose optical axis of the microscope is parallel with the horizontal plane. A prism with special coating is fixed in front of the objective lens, thus, two-part figures can be acquired simultaneously by the microscope with 1.67 to 9.26 micron optical resolution. The relative discrepancy between the two parts can be calculated from image plane coordinate instead of calculating the space transformation matrix. A modified microgripper was designed to clamp meso-scale parts and its effectiveness was confirmed experimentally. Through the use of the other vision system, the insert action can be successfully manipulated. A laser ranger finder was integrated in this micro-assembly system to measure the assembly result.

A new 14-DOF robotic micromanipulator, including eight axes automatically and six axes manually, has been developed for the assembly of LIGA meso-scale flat parts and axle hole parts. The microassembly system with coaxial alignment function (MSCA) system is able to concurrently manipulate all eight axes automatically and six axes manually.

The robotic microassembly is applied in the assembly of meso-scale parts. The new capabilities of the MSCA will allow for the assembly of microsystems more efficiently and more precisely.