This paper describes the design, simulation and fabrication of an inductive angular position sensor on a flexible substrate. The sensor is composed of meandering silver coils printed on a flexible substrate (Kapton film) using inkjet technology. The flexibility enables that after printing in the plane, the coils could be rolled and put inside each other. By changing the angular position of the internal coil (rotor) related to the external one (stator), the mutual inductance is changed and consequently the impedance. It is possible to determine the angular position from the measured real and imaginary part of the impedance, in our case in the frequency range from 1 MHz to 10 MHz. Experimental results were compared with simulation results obtained by in-house developed software tool, and very good agreement has been achieved. Thanks to the simple design and fabrication, smaller package space requirements and weight, the presented sensor represents a cost-effective alternative to the other sensors currently used in series production applications.

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Amorpha fruticosa L. (Fabaceae), known as indigo bush, false indigo bush, false indigo and desert false indigo, is deciduous shrub (1-6 m tall). The woody weed species A. fruticosa has a high environmental adaptability and is present in different environmental conditions. In Vojvodina region (Northern Serbia), it is mostly present near irrigation channels and river banks, especially in alluvial or marshy areas. Since A. fruticosa is continually spreading near river banks, the aim of research was to determine seed bank composition near the Danube River. In 2014, soil sampling was performed at localities with high population of A. fruticosa (3-4 plants at age over two years and 10-14 plants at age 1-2 years). Soil samples were taken from two localities (Futog and Šangaj) with alluvial sandy soil and chernozem near the Danube River. Each sample was sieved through a system of copper sieves of various diameters. After the separation of seeds from samples, they were identified. Significant presence of A. fruticosa seeds (1,914 seeds/m²) was established in a layer of 0-10 cm. In the same soil layer, the significant presence of seeds of Stellaria media (L.) Vill. and Urtica dioica L. were also established. Seeds of A. fruticosa were not found in soil layers 10-20 cm and 20-30 cm. The invasive weed species A. fruticosa produces a large number of seeds in two cycles. The majority of the seeds stay in the upper soil layer, being dispersed by water (hydrochory).

Phytotoxic substances released by invasive plants have been reported to have anti-pathogen, anti-herbivore, and allelopathic activity. The aim of this study was to determine the allelopathic influence of the Ambrosia trifida L. on oxidative stress parameters (the lipid peroxidation process; reduced glutathione (GSH) content; and activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and peroxidase (PX)) and phenolic compounds (total phenolic and tannin content) in maize (Zea mays L.), soybean (Glycine max L.), and sunflower (Helianthus annuus L.) crops to explore the effect of released allelochemicals through A. trifida root on crops. An analysis by HPLC confirmed the presence of protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, and syringic acid as major components in the A. trifida. Based on the obtained results for oxidative stress parameters, it can be concluded that the sunflower was the most sensitive species to A. trifida allelochemicals among the tested crops. The other two crops tested showed a different sensitivity to A. trifida. The soybean did not show sensitivity, while the maize showed sensitivity only 10 days after the sowing.

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In this paper, we performed analytical, numerical and experimental studies on the generation of soliton waves in discrete nonlinear transmission lines (NLTL) with varactors, as well as the analysis of the losses impact on the propagation of these waves. Using the reductive perturbation method, we derived a nonlinear Schrödinger (NLS) equation with a loss term and determined an analytical expression that completely describes the bright soliton profile. Our theoretical analysis predicts the carrier wave frequency threshold above which a formation of bright solitons can be observed. We also performed numerical simulations to confirm our analytical results and we analyzed the space–time evolution of the soliton waves. A good agreement between analytical and numerical findings was obtained. An experimental prototype of the lossy NLTL, built at the discrete level, was used to validate our proposed model. The experimental shape of the envelope solitons is well fitted by the theoretical waveforms, which take into account the amplitude damping due to the losses in commercially available varactors and inductors used in a prototype. Experimentally observed changes in soliton amplitude and half–maximum width during the propagation along lossy NLTL are in good accordance with the proposed model defined by NLS equation with loss term.