Improved Sensor Selection Technique by Integrating Sensor Fusion in Robot Position Estimation

Modelling and reducing uncertainty are two essential problems with mobile robot localisation. Previously we developed a robot localisation system, namely, the Gaussian Mixture of Bayes with Regularised Expectation Maximisation (GMB-REM), which introduced the sensor selection technique. GMB-REM allows a robot"s position to be modelled as a probability distribution and uses Bayes" theorem to reduce the uncertainty of its location. A new sensor selection technique incorporated with sensor fusion is introduced in this paper. Actually the new technique is realised by incorporating with the sensor fusion scheme. Empirical results show that the new system outperforms the previous GMB-REM with sensor selection alone. More specifically, we illustrate that the new technique is able to considerably constrain the error of a robot"s position.     

Suppression of H2S gas generation from the 75Li2S·25P2S5 glass electrolyte by additives

Solid electrolytes in the system Li₂S–P₂S₅ are attractive for all-solid-state lithium batteries since the electrolytes have high lithium ion conductivities and wide electrochemical windows. In particular, the 75Li₂S·25P₂S₅ (mol%) glass showed the highest stability to moisture in the system Li₂S–P₂S₅ because the amount of H₂S gas generated from the glass was the smallest in the system Li₂S–P₂S₅. In this study, several additives such as metal sulfides and metal oxides (FeS, CuO, etc.) were mixed with the 75Li₂S·25P₂S₅ glass in order to suppress H₂S gas generation from the sulfide glasses in air. The addition of more than 30 mol% FeS greatly decreased H₂S gas generation from the sulfide glass in air. In the case of the FeS addition, sulfur crystal was precipitated and the 75Li₂S·25P₂S₅ glass changed to Li₃PO₄ crystal after a reaction with water. On the other hand, the addition of 30 mol% CuO dramatically decreased H₂S gas generation from the sulfide glass in air. In the case of the CuO addition, Cu₃PS₄ crystal was precipitated after the reaction with water. Furthermore, the 75Li₂S·25P₂S₅ glass added with 30 mol% FeS or CuO showed relatively high conductivities of more than 10^?4 S cm^?1 at room temperature. Therefore, the 75Li₂S·25P₂S₅ glass added with FeS or CuO was expected to be a suitable solid electrolyte material for all-solid-state batteries.     

Extension of distance measurement range in a sinusoidal wavelength-scanning interferometer using a liquid-crystal wavelength filter with double feedback control

The optical path difference (OPD) and amplitude of a sinusoidal wavelength scanning (SWS) are controlled with a double feedback control system in an interferometer, so that a ruler marking every wavelength and a ruler with scales smaller than a wavelength are generated. These two rulers enable us to measure an OPD longer than a wavelength. A liquid-crystal Fabry-Perot interferometer (LC-FPI) is adopted as a wavelength-scanning device, and double sinusoidal phase modulation is incorporated in the SWS interferometer. Because of a high resolution of the LC-FPI, the upper limit of the measurement range can be extended to 280 microm by the use of the phase lock where the amplitude of the SWS is doubled in the feedback control. The ruler marking every wavelength is generated between 80 microm and 280 microm, and distances are measured with a high accuracy of the order of a nanometer in real time.     

Synthesis of copolymer beads with various phenolic derivatives attached via different linkages and their antioxidation activity

Macroporous copolymer beads with various phenolic derivatives introduced via three types of linkages—amide, methylene, and ether—were prepared from chloromethyl styrene/tetra(ethylene glycol) dimethacrylate copolymer beads. The antioxidation activity of these phenolic copolymer beads was investigated by the measurement of the inhibition activity against the hydroperoxidation of 1,4-dioxane. The phenolic copolymer beads with the dihydroxybenzene moiety exhibited the highest antioxidation activity, and the antioxidation activity of methylene- or ether-linked phenolic copolymer beads was higher than that of amide-linked copolymer beads. Thus, the antioxidation activity of the phenolic copolymer beads was affected by not only the kinds of phenolic moieties attached but also the type of linkage group. In addition, the swelling of the copolymer beads in an organic solvent was greatly affected by the linkage type of the phenolic copolymer beads. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Antibacterial activity of resin-containing triethylenetetramine side chains and/or thiol groups–metal complexes

Four chelating resins containing triethylenetetramine side chains and/or thiol groups were made from macroreticular 2,3-epithiopropyl methacrylate, styrene–divinylbenzene (DVB), or methyl methacrylate–DVB copolymer beads, and then the resins bearing metal ions such as Ag⁺, Cu²⁺, and Zn²⁺ were made. The antibacterial activity of the resins bearing metal ions against Escherichia coli (E. coli) or Staphylococcus aureus (S. aureus) was investigated. The resins containing thiol groups showed the higher adsorption capacity for silver ions than for other metal ions. The resins, which contain both triethylenetetramine side chains and thiol groups, bearing silver ions (RE-TTA-Ag) exhibited high antibacterial activity against bacteria, especially E. coli, without the residual silver ions in water after contacting with bacteria. The activity of the RE-TTA-Ag did not decrease even after reusing several time. © 1996 John Wiley & Sons, Inc.