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With the continuous development of information technology, computer has been gradually used in people’s daily life. The management and system maintenance of computer room in colleges and universities are trivial and complex. It not only faces a large number of users, but also ensures the normal operation of all computer systems. This work discussed the importance of strengthening the management and maintenance of the computer room in colleges and universities and researched on the problems existing in the management and maintenance of the computer room at the present stage. Subsequently, this work proposed the effective solutions to the problems and carried on a systematic discussion from the aspects of environment maintenance, safety management, hardware management, system maintenance, and software management in order to ensure the maximum utility of computer and the normal business operation of daily work in colleges and universities.

With the rapid development of modern science and technology, computer technology has penetrated into various fields and become an indispensable tool for various industries. And the wide application of computers in daily life, proficiency in computer technology has become a must for all colleges and universities. Therefore, in addition to arranging a large number of computer theory courses for students, colleges and universities should also arrange enough experimental courses for students, and how to arrange reasonable time for each student. The management of traditional laboratories consumes a lot of manpower and energy and experimental course management. Many problems such as chaos are exposed. This paper will analyze and discuss the existing computer experiment management system, and explore ways to improve the efficiency of computer lab use.

Practical teaching is very important for cultivating students’ practical ability and innovative ability. At present, practice teaching of electronic commerce is insufficient, so it is necessary to construct an effective practice teaching mechanism for the major of electronic commerce. This paper puts forward that the teaching practice process should run through the cultivation of students’ independent ability, the teaching process should pay attention to efficiency and effect as well as the combination of basic theory and practical teaching, the teaching practice should pay attention to the mode of cooperation and joint training between schools and enterprises, and practical teaching should pay attention to the various abilities cultivation of the major of electronic commerce, which provides a certain theoretical basis for the establishment of the practical teaching mechanism of electronic commerce.

“Public entrepreneurship and innovation” can alleviate the employment pressure of college students, effectively promote the transformation of China’s economic development mode, maintain the sustained and steady growth of China’s economy, and promote the vertical flow of society and fairness and justice, and increase the income of residents. Nowadays, the primary problem faced by college entrepreneurs and the focus of entrepreneurial issues actively explored by relevant departments in the country 8 are still the bottleneck of the shortage of venture capital. Therefore, it is particularly urgent for the government to accelerate the support of financial institutions for college students’ entrepreneurship. This paper discusses the current situation of college students’ entrepreneurial financial support system. Through the analysis of the problems existing in the needs of college students’ entrepreneurial financial education, this paper puts forward some suggestions for the needs of college students’ entrepreneurial financial education.

In order to identify structural damage locations and extent, a method based on ridge estimation and modal strain energy is presented in this paper. First, structural modal strain energy is given and a modal strain energy sensitivity damage equation is obtained. Then, considering the TikhonovTT regularization theoryTT, a ridge estimation method is proposed to solve the damage equation and ridge parameter of the method is optimized. Simulation results demonstrate that the proposed damage detection method based on ridge estimation and modal strain energy can identify structural damage locations and extent with good accuracy.

In order to study Particle Swarm Optimization (PSO) algorithm and structural damage diagnosis, a method based on PSO algorithm and Evidence theory is presented in this paper. First, structural frequency and modal strain energy are considered as two kinds of information sources, and frequency change method and modal strain energy method are utilized to extract damage information. Then, evidence theory is utilized to integrate the two information sources and preliminarily detect structural damage locations. Finally, the PSO algorithm is used to identify structural damage extent. An improved PSO algorithm is also presented. Simulation results show that the evidence theory can identify the suspected damage locations, and the PSO algorithm can precisely detect the damage extent. It can also be observed that the improved PSO algorithm is obviously better than the simple PSO algorithm.

In order to solve a structural multi-damage identification problem, a two-stage damage identification method based on evidence fusion and improved particle swarm optimization (IPSO) is presented. First, structural modal strain energy and frequency are considered as two kinds of information sources. Then, evidence fusion theory is utilized to integrate the two information sources and preliminarily identify structural damage locations. After the damaged locations are determined, particle swarm optimization (PSO) is used to identify the extent of structural damage. Considering that the search efficiency of a basic PSO is still not very good, some improved strategies are presented, such as mutation position iteration formula, micro-search of an elitist, two convergence conditions, etc. The simulation results demonstrate that the proposed two-stage method can estimate the damage locations and extent with good accuracy.

In order to solve structural multi-damage identification problem, a two-stage damage detection method based on Bayesian theory and immune genetic algorithm (IGA) is presented. First, structural modal strain energy and frequency are considered as two kinds of information sources, and Bayesian theory is utilized to integrate the two information sources and preliminarily identify structural damage locations. After the damaged locations are determined, immune genetic algorithm is used to identify structural damage extent. Considering the search efficiency of the simple IGA is still not very good, some improved strategies are presented, such as culture vaccine, concentration control of the best antibody, and two termination conditions etc. Simulation results show that the two-stage method can precisely identify structural damage locations and extent, and the calculated results of the proposed improved IGA are obviously better than those of both the simple IGA and the genetic algorithm with elitist strategy.

In order to solve structural damage identification problem, a damage identification method based on improved Particle Swarm Optimization (IPSO) is presented. First, structural frequency and modal strain energy are utilized to obtain damage information. Then, evidence fusion theory is utilized to integrate the information and preliminarily identify structural damage locations. After the damaged locations are determined, Particle Swarm Optimization (PSO) is used to identify structural damage extent. Some improved strategies are presented to enhance the search efficiency. The simulation results demonstrate that the proposed method can estimate the damage locations and extent with good accuracy.

Ba0.5Sr0.5TiO3film was successfully fabricated by micro arc oxidation of titanium plate in aqueous solution containing Sr(OH)2and Ba(OH)2for 25 minutes. X-ray diffraction , energy dispersive spectrometer and scanning electron microscopy were used to characterize the crystalline structure, elements composition and surface morphology and HP4284 capacitance prober was used to analyze the dielectric properties of the film. The micro arc oxidation film is mainly composed of tetragonal Ba0.5Sr0.5TiO3 phases and possesses both high dielectric constant of 454.2 and low dielectric loss of 0.052 at the frequency of 100Hz.The surface morphology appeares smooth and homogeneous except that some holes are uniformly distributed outwardly.

Pure titanium plates as anode and mixture of solutions containing 0.2M Sr(OH)2and 0.2M NaOH as electrolyte, titanium plates were microarc-oxidated for 10 minutes. X-Ray Diffraction (XRD) analysis indicated that SrTiO3film was successfully deposited. The MAO film is composed mainly of tetragonal SrTiO3phases and found to possess high dielectric constant of 371.0 at the frequency of 1 kHz. Scanning Electron Microscopy (SEM) and portable roughness tester were used to characterize the surface morphology and roughness values(Ra), The influences of electrolyte concentration, current density and frequency on the surface morphology of SrTiO3film were investigated in detail . several rules were drawn from the results. A kinetics expression was established for the growth of film thickness and agreed well with the experimental results.

In order to solve structural multi-damage identification problem, a two-stage damage detection method based on energy balance equation and evidence fusion is presented. First, a Frequency Change Identification (FCI) method and Modal Strain Energy Dissipation Ratio (MSEDR) method are utilized to preliminarily identify structural damage locations, and then a Fusion Damage Localization (FDL) method based on evidence theory is proposed to precisely detect damage locations. The FDL method mainly utilizes evidence theory to combine both the FCI localization information and the MSEDR localization information. Thus, more precise damage localization information can be acquired. After the damaged locations are determined, an Energy Balance Equation (EBE) index is presented to identify structural damage extent. Considering that strain energy dissipation should be equal to the change of modal strain energy, a quartic EBE equation is deduced, and structural damage extent can be obtained through the solution of the equation. An average quantification index is also proposed to improve identification precision. The simulation results demonstrate that the FDL method can perfectly detect structural damage locations, and the EBE index and average index can identify structural damage extent.

In order to precisely identify the location and extent of structural damage, a two-stage damage detection method using frequency responses and statistical theory is presented in this paper. First, a damage index, which comes from the product of the stiffness changes and measured responses, is proposed. We can utilize degree-of-freedom (d.f.) damage index to localize the damage locations. Then, in order to calculate the extent of damage, a damage quantification formula is deduced from a reduced degree-of-freedom system. Finally, the effect of measurement noise is taken into account in the identification process and the measurement noise sensitivity formula based on statistical theory is presented. The numerical example and analysis demonstrate the excellent performance of the proposed two-stage method to identify damage locations and extent compared with other methods, such as the directness generalized inverse method.

In order to solve the damage detection problem, a damage detection method based on strain energy and evidence theory is presented in this paper. First, an evidence theory method is proposed to identify structural damage locations. Then, structural modal strain energy is utilized to quantify structural damage extents. In general, structural strain energy dissipation should be equal to the change of modal strain energy, according to this theory, a new energy equation is deduced, and structural damage extent can be obtained through the solution of the equation. The simulation results show that the method can perfectly identify damage locations and extents. Therefore, the proposed method is effective for the structural damage identification.

In order to solve the structural optimization problem of long-span transmission tower, topology combination optimization (TCO) method and layer combination optimization (LCO) method based on discrete variables are presented, respectively. An adaptive genetic algorithm (AGA) is proposed as optimization algorithm. Four methods: cross-section size optimization (CSSO) method, shape combination optimization (SCO) method, the TCO method and the LCO method, are utilized to optimize the transmission steel tower, respectively. The topology optimization rules are presented for the TCO method, and the layering optimization rules are presented for the LCO method. A high-voltage steel tower is analyzed as a numerical example to illustrate the performance of the proposed methods. The simulation results demonstrate that the calculated results of both the proposed TCO method and the LCO method are obviously better than those of the CSSO method and the SCO method.

In order to solve structural multi-damage identification problems, a damage detection method based on modal strain energy equivalence index (MSEEI) is presented. First, an accurate expression of modal strain energy (MSE) before and after damage occurs is given. Then, according to the energy equivalence theory that the change in MSE caused by the damage should be equivalent to the energy dissipation caused by the same damage, an energy equivalence equation is deduced. Finally, four roots of the energy equivalence equation are found and a MSEEI is obtained from the four roots. Simulation results demonstrate that the proposed MSEEI method can identify structural damage locations and extent with good accuracy. Identification precision of the proposed method is clearly better than that of the modal strain energy dissipation ratio index (MSEDRI) method.