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The study of the formation and migration of different water bodies is helpful to the rational development and utilization of water resources, and of great significance to the coordinated prevention and control of surface water and groundwater pollution and ecological environment protection. Taking the Jiaozhou Bay north shore shallow groundwater, river water and sea water as the research object, through the acquisition of water chemistry and hydrogen and oxygen stable isotope samples test and analysis, the statistics and Piper diagram were integrated used, different water bodies of water chemical characteristics and influencing factors were analyzed, and in combination with characteristics of hydrogen and the relationship between supply source and transformation was studied by oxygen stable isotopic. The results show that the fissure water of bedrock in the study area is mainly fresh water, and some points are affected by seawater intrusion, showing brackish water characteristics. Quaternary pore water is salt water and its chemical composition is stable. The chemical composition of the river water varies greatly, showing the characteristics of brackish water and salt water. There is a mutual transformation relationship between surface water bodies in the study area. The main source of water in Xiangmao River is atmospheric precipitation. Hongjiang River and Moshui River are mixed water of atmospheric precipitation and sea water, and Moshui River is more affected by sea water mixing than Hongjiang River. The seawater in Jiaozhou Bay is a mixture of river water and standard seawater. There is mutual transformation between groundwater and surface water in the study area. Besides atmospheric precipitation, there is a close hydraulic connection between bedrock fissure water and quaternary pore water, which is affected by seawater intrusion. Quaternary pore water is derived from the mixture of atmospheric precipitation and sea water, which is supplied by surface water or fissure water in bedrock during runoff and experiences evaporation in different degrees. [ABSTRACT FROM AUTHOR]

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When the clear distance between the ramp and the longitudinal slope of the expressway is small, vehicles are easy to be affected by the diverging and merging when going up and down the slope, and the variation of speed is large, which is not conducive to driving safety. Based on the minimum clear distance between the ramp and the longitudinal slope, UC-Win /Road was used to establish the Inlet-uphill and downhill-exit section simulation model, and the experiment was carried out with Forum8 driving simulator and data were collected. The control variable method was used to adjust the characteristic indicators such as the mixing rate of large vehicles and the proportion of diverging and merging to study the real-time variation law of vehicle speed in longitudinal section. A velocity measurement model was built to quantify the relationship between the characteristic indicators and the velocity, and a single factor sensitivity analysis was conducted for the characteristic indicators. The results show that the change of ratio of diverging and merging and the mixing ratio of large vehicles have significant influence on the speed change, and the velocity magnitude and change trend of different vehicle types are quite different. The change of mixing ratio of large vehicles has a great influence on the running state of vehicles in the uphill section, while the change of diverging ratio has a great influence on the running state of vehicles in the downhill section. When the mixing ratio of large vehicles and the ratio of diverging and merging is 30%~40% and 10%~15% respectively, the velocity fluctuation is the largest and the sensitivity is strong. The research results can be used to provide a theoretical basis for vehicle operation management and improvement of safety measures when the clear distance between ramp and the longitudinal slope is small. [ABSTRACT FROM AUTHOR]