Diverity evalution and developing strategies of forestry view of scenic spots:taking Lushan as an example

Diversity indexes of current forestry view, such as dominance degree, fragmentation degree and overcast degree, were evaluated by the software ARCVIEWGIS. And developing strategies to improve diversity were put forward in this paper, that is, combining with the items of forestry tour and enhancing scientific management, and choosing typical trees to change forestry structure on the basis of general conditions of dominance degree, fragmentation degree and overcast degree.

Network Security Situation Evaluation Based on Modified D-S Evidence Theory

With the rapid development of global information and the increasing dependence on network for people, network security problems are becoming more and more serious. By analyzing the existing security assessment methods, we propose a network security situation evaluation system based on modified D-S evidence theory is proposed. Firstly, we give a modified D-S evidence theory to improve the reliability and rationality of the fusion result and apply the theory to correlation analysis. Secondly, the attack successful support is accurately calculated by matching internal factors with external threats. Multi-module evaluation is established to comprehensively evaluate the situation of network security. Finally we use an example of actual network datasets to validate the network security situation evaluation system. The simulation result shows that the system can not only reduce the rate of false positives and false alarms, but also effectively help analysts comprehensively to understand the situation of network security.

An experimental analysis of situation awareness for cockpit display interface evaluation based on flight simulation

Aircraft cockpit display interface （CDI） is one of the most important human-machine interfaces for information perceiving. During the process of aircraft design, situation awareness （SA） is frequently considered to improve the design, as the CDI must provide enough SA for the pilot to maintain the flight safety. In order to study the SA in the pilot-aircraft system, a cockpit flight simulation environment is built up, which includes a virtual instrument panel, a flight visual display and the corresponding control system. Based on the simulation environment, a human-in-the-loop experiment is designed to measure the SA by the situation awareness global assessment technique （SAGAT）. Through the experiment, the SA degrees and heart rate （HR） data of the subjects are obtained, and the SA levels under different CDI designs are analyzed. The results show that analyzing the SA can serve as an objective way to evaluate the design of CDI, which could be proved from the consistent HR data. With this method, evaluations of the CDI design are performed in the experimental flight simulation environment, and optimizations could be guided through the analysis.

Evaluation and prediction of the status of COVID-19 epidemic prevention and control based on the SEIR+CAQ model

This paper analyzes the spread of the COVID-19 epidemic in China,establishes a SEIR^(+CAQ)epidemiologic model that classifies the diagnosed population into asymptomatic,mild,and severe,and considers the condition of an isolated population.First of all,we theoretically analyzed the key problems of the disease-free equilibrium,stability,and basic reproduction number of the model.Then,combined with the actual data,the development trend of the epidemic situation is simulated and compared,and the influence of some important parameters is discussed in the model evaluation part.Finally,based on the theoretical analysis and numerical simulation results,we forecast the future development of the COVID-19 epidemic and put forward some reasonable scientific suggestions for the government to formulate a future epidemic prevention policy.