Background and aims. Espar is a dairy product of probiotic nature that contains useful bacteria and high calcium content. The aim of this study was to analyze effects of daily consumption of Espar on the number of salivary mutans streptococci and the level of calcium content in a population of 15 to 17 year-old female students. Materials and methods. A double-blind randomized crossover study (n...

Adaptive beamforming with Hamiltonian algorithm is proposed for ESPAR antenna. Hamilton’s equations describing the motion of particles are used to solve optimization problems. In an application of Hamiltonian algorithm to ESPAR antenna, the cost function for beamforming is considered as the potential energy. Although the kinetic energy, acted by momentums, does not appear in the issue of the be...

This paper proposes the 2.45 GHz planar Beam Steering Antenna Array for Indoor Positioning Systems. The antenna array consists of a phase shifter based on 4 × Butler matrix, and an four dipole Yagi antennas. By choosing one beams using switching controller, main beam can steer in directions from +37°, –12°, +12° to –36°. has narrow fan wit...

Advanced automotive thermal management systems integrate electro-mechanical components for improved fluid flow and thermodynamic control action. Progressively, the design of ground vehicle heating and cooling management systems require analytical and empirical models to establish a basis for real time control algorithms. One of the key elements in this computer controlled system is the smart th...

To lower costs and reduce latency, a network of adaptive array ground stations, distributed across the United States, is considered for the downlink of a polar-orbiting low earth orbiting (LEO) satellite. Assuming the X-band 105 Mbps transmitter of NASA's Earth Observing 1 (EO-1) satellite with a simple line-of-sight propagation model, the average daily download capacity in bits for a network o...

This paper presents a novel design of wideband circular polarization 2 × microstrip antenna array working at Ka-band frequencies, from 27.5 to 31 GHz. module is highly integrable with new silicon beamformer chips, creating unit cell that can be part large electronically steerable for compact, ultra-low-profile, Satcom-on-the-move (SOTM) platforms. A multi-layer structure fabricated in standard ...

We investigate the switched parasitic antenna (SPA), which is a novel technique for electronically directing the radiation pattern, in a MIMO system. The correlation between the received signal modes are shown to be sufficiently low to yield a diversity gain. The capacity limit using the SPA is investigated for different SPA configurations and it is found that the capacity is comparable with an...

Developing enhanced simulation capabilities has become a significant priority for the Space Communications and Navigation (SCaN) project at NASA as new space communications technologies are proposed to replace aging NASA communications assets, such as the Tracking and Data Relay Satellite System (TDRSS). When developing the architecture for these new space communications assets, it is important...