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The low efficiency of nitrogen (N) fertilizers impels the innovation of current N management strategies in cereal production. Site specific N management is an emerging field providing novel alternatives to current nutrient management practices through canopy sensing. Barley N use efficiency can be enhanced with GreenSeeker proximal sensors, whose optimal utilization requires algorithms. The design of such algorithms required four N rates (0, 50, 100 and 150 kg N ha-1) and in-season sensing of barley canopy reflectance using a handheld GreenSeeker sensor as well as crop N analysis. The N rates produced enough variability in yields, N uptake and normalized difference vegetation index (NDVI) readings together with strong determination coefficients between in-season NDVI values on one hand and on the other hand in-season N uptake (R2=0.68, p

Energy storage system would play a crucial role in the electric and hybrid vehicle applications. This paper presents modeling, identification and validation of the behavior of two energy storage devices, battery and supercapacitor, used for a hybrid energy storage system (HESS) in electric vehicle applications. Besides of both main storage elements, the HESS includes bi-directional DC/DC power converters suitable for power electronic interface between the battery main energy storage system and the supercapacitor. Design and modeling of the DC/DC power converter is discussed in this study. The electric state-space models of both power sources, battery and supercapacitor, are also developed. And following that lead, the identification of both storage components constituting the HESS is carried out via many optimization methods based on laboratory experimental data of an urban electric vehicle. The obtained results show the good performance of the state space developed models comparing with the experimental results from a test bench developed in our laboratory.

In the laboratory of plant physiology of the University of Queensland (Gatton Campus), a seed germination experiment was undertaken on seeds of two Australian native plant species – Rhodanthe floribundato and Acacia aneura. Most Acacia, including A. aneura exhibit a physical dormancy due to the waxy coat covering the seed. Comparably, just a few species of Rhodanthe are studied as to their dormancy. However, they are also known to present different forms of dormancy. To understand and describe these dormancy mechanisms, a seed germination experiment was conducted on Acacia aneura and Rhodanthe floribunda. This experiment will either add to the existing knowledge regarding these species’ dormancy or corroborate them. It is expected that both species display some form(s) of dormancy.