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This work is concerned with the problem of robot localization using standard RFID tags as landmarks and an RFID reader as a landmark sensor. A main advantage of such an RFID-based localization system is the availability of landmark ID measurement, which trivially solves the data association problem. While the main drawback of an RFID system is its low spatial accuracy. The result in this paper is an improvement of the localization accuracy for a standard short-range RFID sensor. One of the main contributions is a proposal of a machine learning approach in which multiple classifiers are trained to distinguish RFID-signal features of each location. Another contribution is a design tool for tag arrangement by which the tag configuration needs not be manually designed by the user, but can be automatically recommended by the system. The effectiveness of the proposed technique is evaluated experimentally with a real mobile robot and an RFID system.

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This study focus on the synthesis of amorphous silicon nanoparticles and understanding the formation mechanism. Counter-flow quenching gases with different flow rates were injected from downstream of the torch to understand the effect of quenching gas on the formation of silicon nanoparticles. Transmission electron microscopy show that nanoparticles with spherical shape and agglomerates consist of smaller particles were synthesized. X-ray diffraction analysis is used to calculate the amorphization degree, which is defined as fraction of amorphous silicon in the silicon nanoparticles including both crystal and amorphous. The obtained results show that higher quenching gas flow rate leads to smaller diameter with higher amorphization degree. Electron diffraction patterns reveal that nanoparticles with diameter less than 10 nm are amorphous and agglomerated together, while for the nanoparticles with diameter larger than 10 nm are crystal. The formation mechanism of amorphous silicon nanoparticles is explained by estimated nucleation temperature and experimental results. Consequently, silicon nucleates at about 2400 K and then silicon vapor condenses on the nucleus. Finally, smaller nanoparticles will keep amorphous phase, while nanoparticles with a larger diameter grow to form crystalline.

Primary psoas abscess is due largely to hematogenous or lymphatic spread under immunocompromised conditions, whereas secondary psoas abscess is due largely to direct spread from adjacent infected structures. Trauma or hematoma within the muscle may predispose to the development of a primary abscess, especially if infection is present prior to injury, despite the absence of previous signs or symptoms of infection. This report describes a 17-year-old female high school student who developed an abscess within her iliacus muscle due to methicillin-susceptible <i>Staphylococcus aureus</i> after running 3 km on a hill as a school exercise. She was positive for antinuclear antibody and had had atopic dermatitis, suggesting that these factors, as well as exercise-related minor trauma or hematoma within the muscle, may have predisposed to abscess formation. She was treated with appropriate antibiotics and surgical drainage, resulting in recovery after 4 weeks.