Recognition and movement in an artificial environment with a bipedal robot

However well we control a walking bipedal robot, the images obtained by a camera are tilted to the left or right, and have small irregularities. This complicates the recognition of an environment by using a camera in a walking robot when the robot cannot move smoothly. The reason for using a bipedal robot is to make the robot as similar as possible to a human in body shape and behavior in order to make collaboration easier. This is difficult to attain with other types of robot such as wheel-driven robots (Sato et al. AROB2008; Fujiwara et al. WMSCI2009). In an artificial environment which mainly consists of vertical and horizontal lines, the tilt angle of camera images must be corrected by using the Hough transformation, which detects lines which are nearly vertical (Okutomi et al. 2004; Forsyth and Ponce 2007). As a result, the robot can successfully recognize the environment with stereo vision using images obtained by correcting the tilted ones.     

A novel method applicable to large-scale active magnetic shielding system which effectively compensates gradient magnetic fields originated from the surrounding buildings

We propose the novel magnetic compensation method which is suitable to compensate gradient magnetic fields. The method is to be applied to a conventional large-scale, tri-axial active magnetic shielding system such as a spacecraft magnetic testing facility. The essences of this method are the adoption of compensation coils which have degrees of freedom in their coil orientations, and their installation position, which is chosen to have certain distances from the center of the shielding area. The method works with at least four compensation coils. In this research, we actually demonstrated the method with a scaled-down experiment. Disturbance magnetic field (B) at the target zone was suppressed from 21.33 nT to −1.54 nT and magnetic field uniformity (ΔB) within the test zone was improved from 2.3 nT to 0.015 nT. In terms of magnetic field gradient, improvement from over 4 nT/m to below 0.5 nT/m was achieved.     

Synthesis and properties of polyethylene and polypropylene containing hydroxylated cyclic units in the main chain

Polyethylene and isotactic polypropylene containing hydroxylated cyclic units were synthesized by copolymerization of ethylene or propylene and cyclodiolefins, dicyclopentadiene (DCPD), 5-vinyl-2-norbornene (VNB), 5-ethylidene-2-norbornene (ENB), with zirconocene catalysts and subsequent hydroboration reaction of residual unsaturated group. The resulting hydroxylated copolymers showed higher glass transition temperature (T_g) than the original and hydrogenated copolymers. Relationship between the cyclodiolefin content and ΔT_g (ΔT_g=difference of T_g between hydroxylated copolymer and hydrogenated copolymer) was given by a straight line independent of the structure of the comonomers. Improvement in shape memory effect was observed in the hydroxylated ethylene-VNB copolymer.     

Absolute frequency stability of a diode-laser-pumped Nd:YAG laser stabilized to a high-finesse optical cavity

We report the frequency stabilization of a diode-laser-pumped monolithic ring Nd:YAG laser locked to a high-finesse optical cavity. With an independent cavity as a frequency discriminator, the absolute frequency noise was measured to be as low as 2 × 10(-2) Hz/Hz(1/2) at the Fourier frequency of approximately 3 kHz. We also measured the heterodyne beat note between two lasers locked to the independent cavities. The beat linewidth is narrower than 30 Hz and the minimum root Allan variance is approximately 6 × 10(-14).     

Higher-order correction to the FDTD method based on the integral form of Maxwell’s equations

We propose a higher-order correction to the finite-difference time-domain (FDTD) method based on the integral form of Maxwell’s equations. We calculate the errors between the numerical and analytic solutions. Numerical solutions are obtained by the original method and our corrected FDTD method to show that the accuracy and reliability of our corrected FDTD method is superior to that of the original FDTD method.     

Fabrication of vertically aligned ultrafine ZnO nanorods using metal-organic vapor phase epitaxy with a two-temperature growth method

We report the fabrication of vertically aligned ultrafine ZnO nanorods using metal-organic vapor phase epitaxy and applying a two-temperature growth method. First, thick nanorods were grown vertically on the substrate at a lower temperature. Then, ultrafine ZnO nanorods with an average diameter of 17.7?nm were grown from the tips of the thick nanorods at a higher temperature. The direction of the ultrafine ZnO nanorods followed that of the preformed vertically aligned thick nanorods. Electron microscopy revealed that the ultrafine nanorods were single crystals and the growth direction was along the c axis. Excellent photoluminescence characteristics of the nanorods were confirmed.     

Synthesis and properties of ethylene‐substituted styrene copolymers

The copolymerization of ethylene and substituted styrenes [RSt's; p‐methylstyrene (MSt), p‐tert‐butylstyrene (BSt), 2‐vinylnaphthalene (VN), and p‐(tert‐butyldimethylsilyloxy)styrene (BMSiOSt)] were investigated with dimethylsilylene(tetramethylcyclopentadienyl)(N‐tert‐butyl)titanium dichloride to yield the corresponding ethylene–RSt copolymers. The substituent on the styrene (St) monomers did not affect the monomer reactivity ratio. The effect of the substituent structure of RSt on the thermal and mechanical properties was studied with differential scanning calorimetry, dynamic mechanical thermal spectroscopy, and elongation testing. The glass‐transition temperature (T_g) of the copolymers increased with increasing RSt content, and the order of T_g was as follows: BSt > VN > MSt = St. A copolymer with p‐hydroxystyrene (HOSt) was successively synthesized by means of deprotection of the copolymer with BMSiOSt. The copolymer showed a much higher T_g than the other copolymers because of the hydrogen connection of its OH groups. The mechanical properties of the copolymer in the glass state, at a lower temperature than T_g, were almost independent of the nature of the RSt. The substituent of the St monomers affected the pattern of the stress–strain curve in the elongation testing in the amorphous state. An improvement in the shape memory effect was observed in poly(ethylene‐co‐BSt). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Submerged Hydraulic Jumps below Abrupt Expansions

In submerged flows below an expanding outlet, both symmetric and asymmetric flows are observed. The hydraulic conditions required to form a symmetric submerged jump are necessary for design purposes. In this study, the flow conditions are presented for the submerged flows at an abrupt-symmetrical expansion. Also, the hydraulic conditions for the formation of a symmetric submerged jump are clarified, and an expression is developed for the transition between symmetric and asymmetric flows. Further, an equation on the length of submerged jumps is derived.     

Thermal and Rheological Properties of Dough and Bread as Affected by Various Cross‐linked Cornstarch Substitutions

Various kinds of cross‐linked cornstarches (CLCSs) were used to substitute for wheat flour (5 and 10%), and thermal and rheological properties of dough and bread were examined. The pastes of the substituted flours had lower gelatinization temperatures and higher viscosities than those of the control. The substitution with low‐swelling waxy CLCS (L‐CWCS) had higher paste consistency and lower transition enthalpy than those with high‐ or low‐swelling non‐waxy CLCS (H‐CNCS or L‐CNCS) or the control. The substitutions with L‐CNCS made harder doughs and higher firmness of breadcrumbs during storage than the others. The specific volumes of breads with cross‐linked cornstarch substitutions were slightly smaller than that of the control because of the lack of gluten. The firmness of bread substituted with L‐CWCS was softer than that with H‐ or L‐CNCS. In addition, the breads with H‐CNCS were softer than that with L‐CNCS. The results showed that the compression stress of dough was highly positively correlated with firmness of breads after storage for one and three days (r = 0.876, P < 0.01 and r = 0.809, P < 0.05, respectively). Also, significant positive correlations were detected between the transition enthalpy of dough and firmness of breads after storage for one and three days (r = 0.840, P < 0.05 and r = 0.853, P < 0.05, respectively), whereas no correlation between transition enthalpies of breadcrumbs and firmness of breads was observed.     

Analysis of volatile compounds in Polished-graded wheat flours using headspace sorptive extraction

Headspace sorptive extraction method was used to determine the volatile flavor compounds of the Polished-graded wheat flours and commonly milled wheat flour (CW). The Polished-graded wheat flours of three fractions, C-1 (100-90%), C-5 (60-50%) and C-8 (30–0%), and CW obtained from a hard-type wheat cultivar ‘1CW’ (No. 1 Canada Western Red Spring) were used in the present study. A total of 48 volatile flavor compounds determined in all samples were common as in the wheat grain or flour. The major volatile compounds in C-1 included methoxybenzene (i.e. 1,4-dimethoxybenzene, 1,2,4-trimethoxybenzene, 1,2-dimethoxybenzene) associated with musty odors, and nitrogen compounds (i.e. trimethylamine, 3(4)-methyl pyridine, and 3-methoxy pyridine). The volatile flavor compounds identified in C-5 and C-8 were similar to those in CW. But, some compounds that have a connection with both oxidation products from unsaturated fatty acids and metabolites of a number of species associated with moldy grains, were more abundant in C-5 and C-8 than in CW. Furthermore, hexanal, methanol, ethanol, hexanol, 1-octen-3-ol, 3-octen-2-one, (E,Z)-3,5-octadien-2-one, (E,E)-3,5-octadien-2-one were considerably abundant in C-5 and C-8.