Research on vehicle handling inverse dynamics based on optimal control while encountering emergency collision avoidance

Vehicle driving safety is the urgent key problem to be solved of vehicle independent development while encountering emergency collision avoidance with high speed. And it is also the premise and one of the necessary conditions of vehicle active safety. A new technique for vehicle handling inverse dynamics which can evaluate the emergency collision avoidance performance is proposed. Firstly, the steering angle input of 3-DOF vehicle mode is established. The steering angle input imposed by driver is the control variable, and accurately tracking the expected path was the control object. The optimal control problem can be converted into a nonlinear programming problem while using the state variables conversion, which was solved by the sequential quadratic programming (SQP) algorithm. The results show that vehicle can well track the expected path in high speed

Urban Ground Covers Influence Soil Characteristics and Beetle Communities in Riparian Zone

Riparian zones are terrestrial habitats adjacent to rivers or streams that frequently undergo environmental fluctuation and offer unique ecosystem services. Previous research has shown that varying ground cover due to urbanization can lead to adverse effects on soil quality and arthropod abundance. This experiment investigates ground cover effects on arthropod communities, soil pH, and conductivity. The ground covers examined in this experiment were control, litter addition, litter removal, and grass addition. Forty plots were constructed in October 2020 in an urban riparian forest within Binghamton University’s Nature Area. Ground arthropods were collected in June, July, and September of 2021 while soil was collected in July and October. Ground arthropods were collected using twenty-four-hour wet pitfall traps and then counted and identified to order and family levels. Arthropod groups primarily consisted of spiders, centipedes/millipedes, beetles, springtails, ants, and mites. In June, we found the highest abundance of beetles in the grass addition (11.0 ± 1.6), followed by the removal (9.8 ± 1.7), and lastly the control (8.7 ± 1.1) and the addition (8.7 ± 1.3). The high abundance of beetles in grass treatment may be attributed to the dietary resources added, while the removal plots create an open habitat space. Results also show a difference in pH and conductivity for each treatment when compared to the control. This suggests that differences in microclimates caused by treatments may alter ground arthropods present and soil characteristics.https://orb.binghamton.edu/research_days_posters_2022/1014/thumbnail.jp

Biomass Accumulation and Carbon Sequestration in Four Different Aged Casuarina equisetifolia Coastal Shelterbelt Plantations in South China

Thousands of kilometers of shelterbelt plantations of Casuarina equisetifolia have been planted to protect the southeast coastline of China. These plantations also play an important role in the regional carbon (C) cycling. In this study, we examined plant biomass increment and C accumulation in four different aged C. equisetifolia plantations in sandy beaches in South China. The C accumulated in the C. equisetifolia plant biomass increased markedly with stand age. The annual rate of C accumulation in the C. equisetifolia plant biomass during 0-3, 3-6, 6-13 and 13-18 years stage was 2.9, 8.2, 4.2 and 1.0 Mg C ha(-1) yr(-1), respectively. Soil organic C (SOC) at the top 1 m soil layer in these plantations was 17.74, 5.14, 6.93, and 11.87 Mg C ha(-1), respectively, with SOC density decreasing with increasing soil depth. Total C storage in the plantation ecosystem averaged 26.57, 38.50, 69.78, and 79.79 Mg C ha(-1) in the 3, 6, 13 and 18-yrs plantation, with most of the C accumulated in the aboveground biomass rather than in the belowground root biomass and soil organic C. Though our results suggest that C. equisetifolia plantations have the characteristics of fast growth, high biomass accumulation, and the potential of high C sequestration despite planting in poor soil conditions, the interactive effects of soil condition, natural disturbance, and human policies on the ecosystem health of the plantation need to be further studied to fully realize the ecological and social benefits of the C equisetifolia shelterbelt forests in South China

Microplastics Reduce Earthworm (Eisenia fetida) Biomass and Impact Behavior

This study aims to understand the impacts of common anthropogenic pollutants on earthworms (Eisenia fetida) and soil health. Earthworms were exposed to high microplastics and low microplastics, high and low salinity, imidacloprid pesticide, and combinations of salinity and pesticide. After 28 days, earthworms reared in different concentrations of microplastics showed significant reduction in biomass. The individual escape assay demonstrated that microplastics significantly reduced the earthworms’ ability to escape the induced stressor. We ran a pilot study for avoidance with the varying treatments and found that earthworms preferred the microplastics and high salt and pesticide environments. We found no effects on soil pH but did observe significant differences in conductivity. Earthworms are essential for soil ecosystems with functions of burrowing and decomposition, therefore further research should be conducted to explore effects of anthropogenic pollutants on their ecology.https://orb.binghamton.edu/research_days_posters_2023/1101/thumbnail.jp

Effects of nitrogen and phosphorus additions on nitrous oxide emission in a nitrogen-rich and two nitrogen-limited tropical forests

Nitrogen (N) deposition is generally considered to increase soil nitrous oxide (N2O) emission in N-rich forests. In many tropical forests, however, elevated N deposition has caused soil N enrichment and further phosphorus (P) deficiency, and the interaction of N and P to control soil N2O emission remains poorly understood, particularly in forests with different soil N status. In this study, we examined the effects of N and P additions on soil N2O emission in an N-rich old-growth forest and two N-limited younger forests (a mixed and a pine forest) in southern China to test the following hypotheses: (1) soil N2O emission is the highest in old-growth forest due to the N-rich soil; (2) N addition increases N2O emission more in the old-growth forest than in the two younger forests; (3) P addition decreases N2O emission more in the old-growth forest than in the two younger forests; and (4) P addition alleviates the stimulation of N2O emission by N addition. The following four treatments were established in each forest: Control, N addition (150 kg N ha(-1) yr(-1)), P addition (150 kg P ha(-1) yr(-1)), and NP addition (150 kg N ha(-1) yr(-1) plus 150 kg P ha(-1) yr(-1)). From February 2007 to October 2009, monthly quantification of soil N2O emission was performed using static chamber and gas chromatography techniques. Mean N2O emission was shown to be significantly higher in the old-growth forest (13.9 +/- 0.7 mu g N2O-N m(-2) h(-1)) than in the mixed (9.9 +/- 0.4 mu g N2O-N m(-2) h(-1)) or pine (10.8 +/- 0.5 mu g N2O-N m(-2) h(-1)) forests, with no significant difference between the latter two. N addition significantly increased N2O emission in the old-growth forest but not in the two younger forests. However, both P and NP addition had no significant effect on N2O emission in all three forests, suggesting that P addition alleviated the stimulation of N2O emission by N addition in the old-growth forest. Although P fertilization may alleviate the stimulated effects of atmospheric N deposition on N2O emission in N-rich forests, this effect may only occur under high N deposition and/or long-term P addition, and we suggest future investigations to definitively assess this management strategy and the importance of P in regulating N cycles from regional to global scales