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  • Author: Y. Ito x
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This paper proposes a novel adaptation method for behavior-based locomotion robot. Utilization of the hierarchical behavior controller concept makes the controller designing process easier and shorter, because the designer can deal with behavior controllers for simple behaviors independently, and coordinate those behavior controllers in order for a robot to perform the objective behavior after finishing the design of the fundamental behavior controllers. Some problems are still remaining. One is how to adjust the behavior coordinator when the objective behavior or robot parameters are slightly changed. We propose a novel method to adjust the behavior coordinator against some changes. This method measures the effects of the fundamental behavior controllers to the total behavior, and changes the activation values for them in fewer trials. This proposed method is applied to the real brachiation robot control. This brachiation robot has redundant mechanism to locomote from branch to branch with 14 actuators like a long-armed ape.

Summary

A detailed examination was made of the behavior and distribution of ash and silica during atmospheric acetic acid pulping and subsequent bleaching of rice straw. Ash-rich pulps (in unbleached pulp, about 18%; and in bleached pulp, 16%) with matchable strength properties for conventional alkaline pulps were obtained from rice straw by acetic acid pulping. More than 50% of the ash and about 75% of the silica in rice straw were retained in the pulp after pulping. Because only those acid-soluble mineral components were dissolved during acetic acid pulping, the ash remained in the pulp consisted mainly of silica (92.9% of the ash in unbleached pulp and 97.3% of the ash in bleached pulp). Although part of the ash dissolved during bleaching, the ash content of bleached pulp was still 15.5%, a value much higher than that in other conventional pulps. This type of ash might be good as a filler for paper. Fractionation analysis and the profile and mapping of silica by scanning electron microscope combined with an energy dispersive X-ray analysis (SEM-EDXA) indicated that the silica in the bleached pulp was located mainly in epidermal cells and not in other elements, such as fibers and parenchyma, and that the silica-rich epidermal cells were scattered throughout the pulp as single cells or in bundles.

Abstract

A monoclinic metastable phase of anorthite composition, CaAl2Si2O8, has been synthesized as an artificial product. Crystals are twinned mostly on a submicroscopic scale. In the cell whose dimensions are a = 8.228(1), b = 8.621(1), c = 4.827(1) Å, β = 90.00(5)°, there are two formula units. The space group is P21. The structure has been worked out with the minimum-function method based upon intensities measured on an automated diffractometer. Final atomic coordinates give an R of 0.06 with isotropic thermal parameters. The structure is a framework in which there can be recognized rings of four tetrahedra like the ones of felspar. The calcium atoms are statistically distributed in two point positions with the occupancies of 0.403(4) and 0.564(5) respectively. The structure has a pronounced pseudosymmetry of Pmnn. The deviation from this higher symmetry is primarily explained by nearly complete order in the Si and Al sites in the framework. A comparison of this structure with that of anorthite has revealed that the mean T–O–T angles at two- and three-coordinated oxygen atoms are smaller than the corresponding angles of anorthite. A mechanism of twinning is suggested in terms of mistakes in the Si and Al placements which may occur in the process of crystal growth.

There is no evidence that the synthetic “orthorhombic CaAl2Si2O8”, described by Davis and Tuttle (1952), is distinct from the present monoclinic phase.

Abstract

Iron oxide films were produced by pulsed laser deposition (PLD) of 57Fe metal in an oxygen atmosphere and their compositions were studied by Mössbauer spectroscopy. The effects of gas-phase reactions were investigated by varying the pressure of O2 gas or an O2/Ar gas mixture. When PLD was performed in a high-pressure O2 atmosphere, the main product in the film was trivalent iron oxide particles. When the O2 pressure was reduced, hematite Fe2O3 became dominant in the film, while wüstite FeO was produced at very low O2 pressures. PLD in an O2/Ar gas mixture produced films of trivalent iron oxide particles and hematite solid, but wüstite was not produced. Increasing the substrate temperature during deposition induced annealing of the films, reducing the lattice defect density. X-ray diffraction patterns were obtained to confirm the assignments, and the surface morphologies of the films were investigated by scanning electron microscopy.