As a new teaching and assessing method in modern Information society,E-portfolios has been widely used in various education fields.E-portfolios has many educational characteristics such as real-time teaching, freedom choosing and formative assessment which are very fit for the social-aided learning of STE.It has the bright future and practical meaning to fulfill E-portfolios in the work of social-aided learning of STE.
Based upon analysis of the diseases of bridge deck pavement encountered in service process of highway bridges,from cement concrete,asphalt concrete,technology and other aspects discussion is made.At the same time prevention and improvement measures are proposed,which has a certain instruction value for construction and maintenance of highway bridges.
This paper briefly introduces with the status quo of higher education,and expatiates with three aspects of teaching,such as reforming traditional teaching concepts,changing rigid teaching methods and implementing various teaching approaches.Through all these discussions,this paper proceeds with the exploration of teaching reformation in the higher education aimed at the innovative spirits and practical skills of college students.
The periodicity of the wars between 1000 and 1900 AD in China was analyzed;it was found that the periodicity of 263 years,98 years,and 72 years was highly significant,and periodicity of 57 years,43 years was remarkably too,the periodicity of 263 years was corresponding to the dynasties alternation.The periodicity of wars is related to the climate change.There was a certain extent correlation between the war frequency and the monsoon precipitation intension.The war frequency increased in arid period,so drought maybe one of the important causes to the outbreak of the war.It might also be noted that due attention should be paid to the social factors as well as climate factors.
Indium gallium zinc oxide (IGZO) thin films were deposited by radio-frequency magnetron sputtering at room-temperature. Then, thermal annealing was conducted to improve the structural ordering. X-ray diffraction and high-resolution transmission electron microscopy demonstrated that the as-deposited IGZO thin films were amorphous and crystallization occurred at 800 and 950 °C. As a result of crystallization at high temperature, the carrier concentration and the Hall mobility of IGZO thin films were sharply increased, which could be ascribed to the increased oxygen vacancies and improved structural ordering of the thin films.
Abstract The degree of natural fracture formation and their link to hydraulic fracturing fractures are critical factors in production in the current large-scale fracturing development of shale gas reservoirs. Any magnitude of fractured reservoir heterogeneity may be described using the Discrete Fracture Network (DFN) model. This paper builds on earlier research by providing an additional summary of the multiscale DFN fracture modeling method, analyzing the fracture occurrence using statistical analysis techniques, analyzing the fracture scale using fractal theory, and determining the fracture development degree by combining the fracture attributes in imaging logging and three-dimensional seismic data. Different-scale fracture network models were developed. Simulating the growth of hydraulic fractures accurately using Mohr Coulomb and Barton Bandis criteria, this study also takes into account the interaction between natural and hydraulic fractures, as well as the physical properties of the rock (e.g., elastic modulus, Poisson’s ratio), closure pressure, crustal stress field, and other factors. The fracture network information, sitmulated reservoir volume, stress shadow and other attributes obtained from fracturing simulation can further analyze and evaluate the effect of fracturing simulation, and optimize the well location deployment plan and construction plan in combination with geological engineering conditions.
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