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MBA education has become the fastest growing segment of education in China in recent years and a segment that can now be considered indispensible. However, how best to teach it has long been a source of debate. One of the key issues is how to match student traits with teaching methods. While engaged as teachers of marketing management, the authors collected data by questionnaire, carried out empirical research and data comparison, and undertook contingency analysis. It was found that different personal traits in students lead to different attitudes towards teaching methods. A student’s major in college, gender, and sector of employment has little influence on attitudes towards teaching methods, while age, the most sensitive factor, plays the biggest role, followed by job and class. Therefore, these factors should be taken into consideration when arranging classes, developing the curriculum, and planning teaching methods.

To evaluate the effect of Collagen cross-linking on the prevention of melting in rabbit corneas after alkali burn.Twenty New Zealand white rabbits were randomly divided into model control group and collagen cross-linking treatment group. The second group of rabbits received collagen cross linked treatment. Both groups were applied with antibiotic eye drops to prevent infection. The corneas were evaluated for melting, opacity, pathological and immunohistochemistry, record the changes when 28 days after the animals were killed.In the control group, 6 out of 8 rabbits showed corneal melting after injury (14±4) days, while two corneal perforated. In collagen cross-linking treatment group, one rabbit showed corneal melting after injury 23 days, without corneal perforation; corneal dissolution rate between the two groups was significantly different (P0.05). Pathological examination suggested that in the treatment group, mild corneal edema, mild damage to collagen fibers, inflammatory cell infiltration was significantly less than the control group. Immunohistochemistry showed that corneal collagen fibers arranged in neat rows in the control group.Collagen cross-linking treatment not only can prevent and delay the corneal melting after alkali burn, but also can reduce the destruction of corneal collagen fibers and infiltration of inflammatory cells in the corneal tissue.

Boundary element method (BEM) is widely used in engineering analysis, especially in solving the transient heat conduction problem because of the advantage that only boundary of the problem needs to be discretized into elements. The general procedure of solving the variable-coefficient transient heat conduction problem by using the BEM is as follows. First, the governing differential equations are transformed into the boundary-domain integral equations by adopting the basic solution of the linear and homogeneous heat conduction problemGreen function. Second, domain integrals in the integral equation are converted into boundary integrals by the radial integral method or the dual reciprocity method. Finally, the time difference propulsion technology is used to solve the discrete time differential equations. A large number of practical examples verify the correctness and validity of the BEM in solving the variable coefficient of transient heat conduction problem. However, two deficiencies are encountered when the system of time differential equations is solved with the time difference method, i.e., one is the stability of the algorithm, which is closely related to the time step size, and the other is time-consuming when the freedom degree of the problem is large and all specified time steps are considered, because a system of linear equations needs to be solved in each time step. Therefore, in this paper we present a reduced order model analysis method of solving the variable-coefficient transient heat conduction problem based on BEM by using the model reduction method of proper orthogonal decomposition (POD). For variable-coefficient transient heat conduction problems, the discrete integral equations which are suitable for order reduction operation are deduced by using the BEM, the reduced order model is established by using the model reduction method of POD, and a lowdimensional approximate description of the transient heat conduction problem under time-varying boundary condition is obtained by projection of the initial discrete integral equations on some few dominant POD modes obtained from the problem under constant boundary conditions. First, for a variable coefficient transient heat conduction problem, boundary-domain integral equations are established and the domain integrals are transformed into boundary integrals by using the radial integration method. Second, the time differential equations with discrete format which is suitable for order reduction operation are obtained by reorganizing the integral equations. Third, the POD modes are developed by calculating the eigenvectors of an autocorrelation matrix composed of snapshots which are clustered by the given results obtained from experiments, BEM or other numerical methods for transient heat transfer problem with constant boundary conditions. Finally, the reduced order model is established and solved by projecting the time differential equations on reduced POD modes. Examples show that the method developed in this paper is correct and effective. It is shown that 1) the low order POD modes determined under constant boundary conditions can be used to accurately analyze the temperature field of transient heat conduction problems with the same geometric domain but a variety of smooth and time-varying boundary conditions; 2) the establishment of low order model solves the problem of heavy workload encountered in BEM where a set of large linear equations will be formed and solved in each time step when using the time difference method to solve the large time differential equations.

The new findings can be outlined as follows: Two new simple auxiliary equations which are required to supplement the fundamental boundary integral equations in solving traction-discontinuity problems using multiple-node technique are derived from the symmetric property and the equilibrium equations of the stress tensor. These equations have been used to deal with the corners and edges of single region and multi-region problems. A sub-structure algorithm is developed for solving multi-region problems with corners and edges, using the derived auxiliary equations. This algorithm can deal with nodes where more than two materials intersect.A novel infinite element formulation suitable for multi-layered media was developed. In particular, a set of useful analytical expressions was derived for evaluating strongly singular surface integrals over the infinite surface. A set of unified elastoplastic constitutive relationships dealing with hardening, softening and ideal plasticity behaviour is derived from the Il'iushin postulate in strain space. These relationships are suitable for both small and finite deformation rate-independent elastoplastic problems. Some new identities are derived for the initial stress and strain kernels. Based on these, a new transformation technique from domain integrals to cell boundary integrals is developed, for accurate evaluation of the strongly singular domain integrals pertaining to interior stresses. Two new iterative schemes are introduced for the first time in the incremental variable stiffness method for solving the non-linear system of equations. In particular, in the second one, a novel assembly process was proposed, in which the system equations are expressed in terms of the plastic multiplier.These formulations have been implemented within a Fortran computer code and illustrative numerical examples have been solved to demonstrate its practical utility.