Design of thick film microstrip lowpass filters

This paper presents the CAD of RF and microwave filters such as shielded single layer thick film lowpass filters for wireless communication systems. The performances of the filter were investigated and the optimisation of filter elements was performed

Antlia B: A Faint Dwarf Galaxy Member of the NGC 3109 Association

We report the discovery of Antlia B, a faint dwarf galaxy at a projected distance of similar to 72 kpc from NGC 3109 (M-V similar to -15 mag), the primary galaxy of the NGC 3109 dwarf association at the edge of the Local Group. The tip of the red giant branch distance to Antlia B is D = 1.29 +/- 0.10 Mpc, which is consistent with the distance to NGC 3109. A qualitative analysis indicates the new dwarf \u27s stellar population has both an old, metal-poor red giant branch (greater than or similar to 10 Gyr, [Fe/H] similar to -2), and a younger blue population with an age of similar to 200-400 Myr, analogous to the original Antlia dwarf, another likely satellite of NGC 3109. Antlia B has H I gas at a velocity of v(helio, H I) = 376 kms(-1), confirming the association with NGC 3109 (v(helio) = 403 km s(-1)). The H I gas mass (M-H I = 2.8 +/- 0.2 x 10(5) M-circle dot), stellar luminosity (M-V = -9.7 +/- 0.6 mag) and half light radius (rh = 273 +/- 29 pc) are all consistent with the properties of dwarf irregular and dwarf spheroidal galaxies in the Local Volume, and is most similar to the Leo P dwarf galaxy. The discovery of Antlia B is the initial result from a Dark Energy Camera survey for halo substructure and faint dwarf companions to NGC 3109 with the goal of comparing observed substructure with expectations from the Lambda+Cold Dark Matter model in the sub-Milky Way regime

The Satellite Luminosity Function of M101 into the Ultra-Faint Dwarf Galaxy Regime

We have obtained deep Hubble Space Telescope (HST) imaging of four faint and ultra-faint dwarf galaxy candidates in the vicinity of M101 - Dw21, Dw22, Dw23 and Dw35, originally discovered by Bennet et al. (2017). Previous distance estimates using the surface brightness fluctuation technique have suggested that these four dwarf candidates are the only remaining viable M101 satellites identified in ground based imaging out to the virial radius of M101 (D~250 kpc). Advanced Camera for Surveys imaging of all four dwarf candidates shows no associated resolved stellar populations, indicating that they are thus background galaxies. We confirm this by generating simulated HST color magnitude diagrams of similar brightness dwarfs at the distance of M101. Our targets would have displayed clear, resolved red giant branches with dozens of stars if they had been associated with M101. With this information, we construct a satellite luminosity function for M101, which is 90% complete to M_V=-7.7 mag and 50% complete to M_V=-7.4 mag, that extends into the ultra-faint dwarf galaxy regime. The M101 system is remarkably poor in satellites in comparison to the Milky Way and M31, with only eight satellites down to an absolute magnitude of M_V=-7.7 mag, compared to the 14 and 26 seen in the Milky Way and M31, respectively. Further observations of Milky Way analogs are needed to understand the halo-to-halo scatter in their faint satellite systems, and connect them with expectations from cosmological simulations.Comment: 9 Pages, 3 Figures, 1 Table, Accepted by ApJ

Opportunities for Precision Agriculture in Serbia

The aim of this paper is to analyze the factors leading to low adoption rate of precision farming in Serbia and to describe steps being taken by BioSense institute to increase it. The majority of the arable land in Serbia is grown by small family owned and operated farms most of which are in the range of 2 to 5 ha making them highly unsustainable. Only 16% of the arable land is managed by agricultural companies and cooperatives. We believe that the adoption of advanced technologies with the currently available precision farming solutions is low among the small farmers due to the small size of the agricultural fields and their inability to invest in technologies. Therefore BioSense institute aims to develop low cost, easy to use precision farming solutions that can be applied anywhere regardless of size, the type and age of agricultural machinery used by the farmers and make IT an important tool to drive small farms towards sustainability. With the new applications developed by BioSense all farmers, even small, can benefit from the diffusion of IT into agriculture making precision farming widely accepted in the years to come. In the framework of the “Digital Agriculture of Serbia” program, several technologies are being developed in the areas of nano and microelectronic in-situ sensors, robotic platforms, genotyping/phenotypic, remote sensing (UAS, satellites), internet of things (IoT), and big data analytics as a means to create new information and extract new knowledge that is not otherwise available. A web-based and android-based digital platform named “AgroSense” was recently released for public use and got widely accepted with a large number of large, medium and small farmers registering to the system. The platform brings the benefits of IT to the end users providing free and paid tools (for advanced users) for better decision making. It is also an excellent tool for big data collection that will create new agronomic knowledge. We foresee a great potential for advancing and modernizing farming in Serbia leading towards a more sustainable and environmentally friendly agriculture