Soil nitrate N as influenced by annually undersown cover crops in spring cereals

Cover crops can reduce leaching and erosion, introduce variability into crop rotations and fix nitrogen (N) for use by the main crops. In Finland, undersowing is a suitable method for establishing cover crops in cereals. The effect of annual undersowing on soil nitrate N was studied at two sites. Red clover (Trifolium pratense L.), white clover (Trifolium repens L.), a mixture of red clover and meadow fescue (Festuca pratensis Huds.), and westerwold ryegrass (Lolium multiflorum Lam. var. westerwoldicum) were undersown in spring cereals during six successive seasons, and a pure stand of cereal was grown in two years after that. In all years, the soil nitrate N was measured in late autumn, and in addition in different times of the season in last four years. The effect of undersowing on soil NO3-N content was generally low, but in one season when conditions favoured high N leaching, westerwold ryegrass decreased soil NO3-N. The negligible increase of N leaching risk in connection with undersowing clovers, associated with late autumn ploughing, supports the use of clovers to increase the cereal grain yield. The highest levels of soil NO3-N were recorded at sowing in spring irrespective of whether a crop was undersown or not. NO3-N contents were higher in sandy soil than in silt. Undersowing can be done annually in cereal cultivation either to fix or catch N. No cumulative effects on soil nitrate N were associated with undersowing after six years

Paving the Roadway for Safety of Automated Vehicles: An Empirical Study on Testing Challenges

The technology in the area of automated vehicles is gaining speed and promises many advantages. However, with the recent introduction of conditionally automated driving, we have also seen accidents. Test protocols for both, conditionally automated (e.g., on highways) and automated vehicles do not exist yet and leave researchers and practitioners with different challenges. For instance, current test procedures do not suffice for fully automated vehicles, which are supposed to be completely in charge for the driving task and have no driver as a back up. This paper presents current challenges of testing the functionality and safety of automated vehicles derived from conducting focus groups and interviews with 26 participants from five countries having a background related to testing automotive safety-related topics.We provide an overview of the state-of-practice of testing active safety features as well as challenges that needs to be addressed in the future to ensure safety for automated vehicles. The major challenges identified through the interviews and focus groups, enriched by literature on this topic are related to 1) virtual testing and simulation, 2) safety, reliability, and quality, 3) sensors and sensor models, 4) required scenario complexity and amount of test cases, and 5) handover of responsibility between the driver and the vehicle.Comment: 8 page

Time budget and lying synchronisation of cows in conventional and automatic milking system departments

We compared the time budget and synchronised lying behaviour of cows in a conventional and in an automatic milking systems, both situating inside the same barn

Radiological environmental monitoring at the ESS facility – Annual report 2020

Results from the radiological environmental monitoring of the European Spallation Source (ESS) are presented for year 2020.Among the 63 environmental samples analysed for gamma emitting radionuclides, no elevated levels of anthropogenic radioactivity were observed. All samples (except two samples of lichen) had activity concentrations below the MDA for the natural radionuclides as well as 137Cs, and normal levels of 40K. In sewage sludge, detectable levels of 177Lu and 1311 were observed in samples that were measured within one week after sampling.Mobile gamma spectrometry surveys were carried out around ESS and MAX IV (when operating at high frequency during a test run). No deviating radiation levels were observed.The samples analysed for their 3H activity concentration (120 samples) were generally below the detection limit using the current procedure, instrumentation and analysis time (MDA typically 1.6 Bq L-1). The results show no evidence of any local contamination of 3H in Lund during 2020.The 14C data in the 26 samples of grass, fruits, berries, crops, milk, honey and meat of in the Lund area and in southern Sweden is consistent with the declining 14C specific activity in atmospheric CO2. Seasonal variations were observed in the 14C data. No evidence of anthropogenic 14C contamination in the Lund area was noted during 2020.The report presents the first base-line measurements of 129I (10 samples) in the ESS environmental monitoring programme. The 129I activity concentrations ranged between (3.18 ± 0.20)∙1011 atoms/kg d.w. for grass and (1.31 ± 0.03)∙1013 atoms/kg d.w. for moss. These values are in the expected range

Modeling of Long Term Memory Effects in RF Power Amplifiers with Dynamic Parameters

This paper presents a new radio frequency power amplifier behavioral model that is capable of modeling long term memory effects. The proposed model is derived by assuming linear dependence of the parameters of a conventional model to a long term memory parameter, which enables the model to better track the signal-induced changes of the power amplifier electrical behavior. The model is experimentally tested and shows a 2-3 dB improvement compared to common behavioral models