Global NEST Journal

In order to solve the problems of poor accuracy and long time-consuming of traditional methods in the assessment of sudden oil spill pollution from ships, this paper takes the navigation area in the South China Sea as the research object and proposes to build the assessment model of ship oil spill pollution. Based on the analysis of the transportation advantages of the South China Sea navigation area, the probability of ship collision and the relationship between the probability of ship oil spill and the ship tonnage are obtained. Based on the probability of ship oil spill in the South China Sea navigation area, the evaluation index system of oil spill pollution in the South China Sea navigation area is constructed to determine the oil spill pollution index and pollution level, and to determine the oil spill pollution level The weight of oil pollution index is used to build the assessment model of sudden oil spill pollution in South China Sea navigation area. The experimental results show that the accuracy of the evaluation model is always maintained at 90% and the evaluation time is short.

With the increasing demand for marine resources, the marine ecological environment system is gradually destroyed. The traditional allocation of marine resources has been unable to meet the global resource search, resulting in poor distribution uniformity of marine resources and high packet loss rate of resource allocation. Therefore, an optimal allocation method of sea resources based on ecological environment protection is proposed. Based on the concept of ecological protection, this method builds an evaluation index system for the allocation of Marine resources by measuring the loss of Marine spatial resource assets, and calculates the evolution trend and coordination of Marine ecology according to the weight of evaluation index. A robust optimization method for the optimal allocation of sea resources is established by obtaining the spatial differences in the allocation of sea resources. The experimental results show that the proposed method is more uniform in the distribution of sea resources and has a lower packet loss rate.

High-speed railway (HSR) is severely affected by precipitation disasters. There are many studies on precipitation and precipitation disasters, most of which are precipitation and analysis of disasters caused by precipitation, and few explain climate changes caused by precipitation. This paper uses surface meteorological observation data within 90 km along the Jiangsu section of the Beijing-Shanghai HSR to study the characteristics of precipitation along the line in 2016 ~ 2018 and the characteristics of climate change before the occurrence of precipitation events. This paper presents that when air pressure along the HSR with a relatively low level and a higher probability of precipitation. The low temperatures in April, June and July are more likely to produce precipitation. Correlations analysis shows that the three types of precipitation events are different. The time scale of the correlation between temperature and pressure changes before the occurrence of mild to moderate precipitation events is farther, and the temperature and short-term pressure changes 6 hours before the occurrence of heavy precipitation events. In contrast, the air pressure and temperature within 2 hours before the occurrence of extreme precipitation change rapidly and have a strong correlation, which indicates the occurrence of extreme events.

An experimental study was carried out to investigate the energy dissipation characteristics of sea grass in a dam break flume. Dam break flows were generated in a flume. A steel ball was subjected to the dam break flow, and then climbed on a slope. Artificial sea grass was used as the energy dissipation plant. In the study, the characteristics (such as wave height, wave velocity, Froude number) of the dam break flow were investigated, the ball subjected to the dam break flow was observed, some impact factors of ball climbing height were explored. Results show that, the ball climbing height increases with increasing reservoir water level and decreasing ball diameter. The relative ball climbing height decreases with increasing relative distance and increasing relative grass height. The relative ball climbing height shows logarithmic correlation with relative reservoir water level. The energy dissipation coefficient of the sea grass changed with reservoir water level, with the average value of 0.34 in this study.