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• The spatial variation of sediment connectivity in small watershed was quantified by IC. • Significant spatial variation and autocorrelation were detected in IC in black soil region. • Topographic and anthropogenic factors were main determinants of sediment connectivity spatial variation. Connectivity has become an important indicator of the sediment transfer potential through sediment sources to catchment sinks. Connectivity plays a vital role in investigating the rate of soil erosion caused by runoff and sediment output across the watershed landscape. However, there have been few quantitative studies on the spatial variations in sediment connectivity in the black soil region of Northeast China. Seven classic watersheds in the northeast black soil region were selected to discover spatial variations in sediment connectivity and their influencing factors. The connectivity index (IC) was used to study the spatial variation of sediment connectivity, and the weight of IC was calculated using the vegetation cover management factor (C), which reflected the influence of human activities on the soil erosion process caused by cultivated land expansion and encroachment of forest grassland. The redundancy analysis method (RDA) was used to determine the main factors affecting the spatial variation of IC. The results showed that IC decreased from north (0.45) to south (0.12). The spatial variations of watersheds in sediment connectivity showed significant spatial heterogeneity. IC was correlated with topographic, climatic, and artificial management characteristics at 0.01 or 0.05 levels except soil structural index; RDA results showed that topography and human activities were the main factors affecting sediment connectivity. Topographic and climatic factors explained more sediment connectivity changes in the southern watersheds than in the northern watersheds, while the human activities factor explanation was the opposite of topographic factors. Human activities refer to changes in vegetation cover and soil structure and properties resulting from human logging and farming that affect sediment connectivity. [ABSTRACT FROM AUTHOR]

To control driving speed at intersections and assist drivers in making accurate decisions, a vehicle–road collaborative decisionmaking system for the active safety of intersections was developed. The system is divided into three modules: information collection, decision-making control, and intelligent underground lamps. According to the signal phase of intersections and the speed information of approaching vehicles, the auxiliary decision-making model is established based on an analysis of the dynamic characteristics of the dilemma zone. The state of the dynamic yellow light and intelligent underground lamps are controlled based on judgment results. The intelligent underground lamps can be flexibly switched between the three states, and the driver can be alerted by vision. In addition, the dynamic yellow light time can effectively avoid the risk of intersection accidents, shorten the time delay caused by conservative driving behavior, and improve the overall robustness of the road network. [ABSTRACT FROM AUTHOR]