Constructing a Teaching Evaluation Model for the Course of Beijing World Cultural Heritage Based on Dynamic Assessment Theory

The rapid development of international tourism has led to an increasing demand for English professionals. In order to meet this demand, universities have placed greater emphasis on the quality and level of teaching in the courses of tourism English. This paper proposes a dynamic evaluation model for tourism English courses, based on the principles of dynamic assessment theory, such as process-orientation, evaluation-teaching integration, and multiple interactions. Taking the course of Beijing World Cultural Heritage as an example, the model is instantiated to demonstrate the feasibility of applying dynamic assessment theory to tourism English courses and this model helps to provide a reference for the evaluation methods of English courses.

Environmental impact assessment of magnesium alloy automobile hub based on life cycle assessment

In order to find out the impact of aluminum alloy hub replaced by the magnesium alloy hub on environment,the resource consumption,energy consumption and pollutant emission during hub production and their service life of the two types of hubs are investigated based on the life cycle assessment(LCA)theory.The results indicate that the adverse impact on environment can be effectively reduced by the application of magnesium alloy hubs.Compared with aluminum alloy hubs,the global warming potential(GWP)and human toxicity potential(HTP)are reduced by 39.6%and 24.0%,respectively.CO2 is the main pollutant in the life cycles of the two kinds of hubs,which is generated throughout the whole life cycle including the fabrication process and the service life,while the pollutants of particles mainly come from the fabrication stage.Compared with the aluminum alloy hubs,the green effect brought by magnesium alloy hubs is mainly due to the reduction of fuel consumption caused by weight loss.

Handling epistemic uncertainties in PRA using evidential networks

In order to overcome the limitations of traditional methods in uncertainty analysis, a modified Bayesian network(BN), which is called evidence network(EN), was proposed with evidence theory to handle epistemic uncertainty in probabilistic risk assessment(PRA). Fault trees(FTs) and event trees(ETs) were transformed into an EN which is used as a uniform framework to represent accident scenarios. Epistemic uncertainties of basic events in PRA were presented in evidence theory form and propagated through the network. A case study of a highway tunnel risk analysis was discussed to demonstrate the proposed approach. Frequencies of end states are obtained and expressed by belief and plausibility measures. The proposed approach addresses the uncertainties in experts' knowledge and can be easily applied to uncertainty analysis of FTs/ETs that have dependent events.

Negative exponential behavior of image mutual information for pseudo-thermal light ghost imaging： observation, modeling, and verification

When using the image mutual information to assess the quality of reconstructed image in pseudothermal light ghost imaging, a negative exponential behavior with respect to the measurement number is observed. Based on information theory and a few simple and verifiable assumptions, semi-quantitative model of image mutual information under varying measurement numbers is established. It is the Gaussian characteristics of the bucket detector output probability distribution that leads to this negative exponential behavior. Designed experiments verify the model.