Stability Criterion of Biped Robot on Rough Terrain

This paper presents a stability criterion for biped robots on rough terrain. On rough terrain, which is not perpendicular to gravity, a robot may not fall even though its center of mass is out of the area of the supported polygon defined by the conventional VHP (virtual horizontal plane) method. This is because there exists a certain force opposing the torque that causes the robot to fall down. We propose a new measure for strictly judging the limit of falling considering all the forces acting on the contact points. Numerical simulations and experimental results are also shown, which verify the proposed method.     

Adaptive system identification using robust LMS/F algorithm

Adaptive system identification (ASI) problems have attracted both academic and industrial attentions for a long time. As one of the classical approaches for ASI, performance of least mean square (LMS) is unstable in low signal‐to‐noise ratio (SNR) region. On the contrary, least mean fourth (LMF) algorithm is difficult to implement in practical system because of its high computational complexity in high SNR region, and hence it is usually neglected by researchers. In this paper, we propose an effective approach to identify unknown system adaptively by using combined LMS and LMF algorithms in different SNR regions. Experiment‐based parameter selection is established to optimize the performance as well as to keep the low computational complexity. Copyright © 2013 John Wiley & Sons, Ltd.     

Combining polymers with diamond-like carbon (DLC) for highly functionalized materials

Diamond-like carbon (DLC) can be effectively coated on polymer surfaces in order to modify polymers for highly functionalized materials. DLC films have been widely used for many industrial applications due to their outstanding physical properties such as high hardness, wear resistance and biological compatibility. Polymers, on the other hand, can create soft, flexible, highly absorbent and cost-effective materials by selecting or controlling their molecular structures. The DLC films coated on such polymer substrates have been investigated and extensively used because recently, quite a few applications of the polymer-DLC composites to e.g. gas barrier films and biocompatible medical devices have been proposed. In this article, we discussed the barrier properties, especially the gas barrier properties and the biocompatibility of DLC-coated polymers, after summarizing the fundamentals of DLC and polymers, followed by the explanation as to the adhesion and fracture behavior of DLC and polymers, which is crucial for the creation of a new polymer-DLC composite.     

Cutting characteristics of twist drill having cutting edges for drilling and reaming

In this study, the cutting characteristics of a drill reamer, which has conventional twist drill cutting edges appended for reaming, were investigated. A drill reamer has three types of cutting edges, whose roles are drilling, semi-finishing, and finishing. The cutting characteristics of a conventional twist drill were compared to those of the drill reamer. The cutting characteristics were evaluated using the thrust force, cutting torque, surface roughness, wear behavior of the cutting edges, and cutting edge temperature. The study used a workpiece made of carbon steel. The temperature of the cutting edge for reaming reached a maximum value of approximately 420°C, even though the depth of the cut was very small. The inner surface roughness with the drill reamer was superior to that with the conventional drill, even under dry and low-speed cutting conditions. The abrasive wear observed on the margin face of the cutting edge used for reaming.     

Non‐homologous end joining‐mediated functional marker selection for DNA cloning in the yeast Kluyveromyces marxianus

The cloning of DNA fragments into vectors or host genomes has traditionally been performed using Escherichia coli with restriction enzymes and DNA ligase or homologous recombination‐based reactions. We report here a novel DNA cloning method that does not require DNA end processing or homologous recombination, but that ensures highly accurate cloning. The method exploits the efficient non‐homologous end‐joining (NHEJ) activity of the yeast Kluyveromyces marxianus and consists of a novel functional marker selection system. First, to demonstrate the applicability of NHEJ to DNA cloning, a C‐terminal‐truncated non‐functional ura3 selection marker and the truncated region were PCR‐amplified separately, mixed and directly used for the transformation. URA3⁺ transformants appeared on the selection plates, indicating that the two DNA fragments were correctly joined by NHEJ to generate a functional URA3 gene that had inserted into the yeast chromosome. To develop the cloning system, the shortest URA3 C‐terminal encoding sequence that could restore the function of a truncated non‐functional ura3 was determined by deletion analysis, and was included in the primers to amplify target DNAs for cloning. Transformation with PCR‐amplified target DNAs and C‐terminal truncated ura3 produced numerous transformant colonies, in which a functional URA3 gene was generated and was integrated into the chromosome with the target DNAs. Several K. marxianus circular plasmids with different selection markers were also developed for NHEJ‐based cloning and recombinant DNA construction. The one‐step DNA cloning method developed here is a relatively simple and reliable procedure among the DNA cloning systems developed to date. Copyright © 2013 John Wiley & Sons, Ltd.     

Cultural variations on optimistic and pessimistic bias for self versus a sibling: Is there evidence for self-enhancement in the West and for self-criticism in the East when the referent group is specified?

A culturally relevant framework was used to examine variations on optimistic and pessimistic bias in Westerners and Easterners. Study 1 showed that 136 European Americans compared with 159 Japanese were more likely to predict typical positive events to occur to self than to a sibling. The opposite pattern emerged in the prediction of typical negative events. Study 2 replicated these findings on the basis of predictions for atypical events in 175 European Americans and 130 Japanese. Across both studies, within-groups analyses indicated that European Americans held an optimistic bias in the prediction of positive and negative events, whereas Japanese held a pessimistic bias for negative events. These findings are taken to offer support for presumed cultural differences in self-enhancement and self-criticism between Westerners and Easterners, respectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fibre management technique for optical device integration oncircuit board with hundreds of optical connections

The authors present a technique for fibre management on a circuit board, which utilises newly-developed, flexible optical fibre circuits and multifibre physical contact connectors. The technique achieves compact fibre wiring and easy fibre connection for hundreds of fibres on a circuit board. The authors have fabricated a compact 8×16 delivery and coupling switch board using the technique     

Mechanism of inhibition of H+, K(+)-ATPase by sodium 2-[[4-(3- methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl]-1H-benzimidazole (E3810)

Sodium 2-[[4-(3-methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl ]- 1H-benzimidazole (E3810) and omeprazole inhibit gastric acid secretion through inhibition of the activity of H+, K(+)-ATPase present in parietal cell membrane vesicles, by chemical modification of SH groups in the enzyme molecule. In order to clarify the mechanism of the chemical modification, reaction products of E3810 and omeprazole with 2-mercaptoethanol under acidic conditions (pH 3, 4, 5, 6) were isolated by HPLC, and subjected to structural analysis by UV, 1H-NMR and mass spectrometry. E3810 and omeprazole appeared to undergo two kinds of reactions, affording disulfide-type products (type I reaction) and sulfide-type products (type II reaction). The rates of these reactions were determined by HPLC, and the stability of the products in the presence and absence of glutathione was investigated. In the case of E3810, type I reaction was found to proceed faster than type II reaction at every pH value studied. The type I reaction of E3810 was faster than that of omeprazole. The rate of type I reaction decreased at pH 5 and 6, especially for omeprazole, and the contribution of type II reaction increased as the pH of the reaction mixture was increased. The sulfide-type modification products were stable, whereas the formation of the disulfide-type modification products was reversed by the action of endogenous SH compounds such as glutathione. These results suggest that higher inhibitory activity of E3810 against gastric acid secretion and faster recovery of the enzyme activity after inhibition by E3810 can be expected, as compared with those of omeprazole.     

Gamma Ray Generation Through a 1.064 μM Laser Beam

We are exploring to process nuclear waste through nuclear transmutation method with γ ray irradiation. The γ ray employed for transmutation is generated in the way of Compton backscattering. Preliminary experiment is being developed on the NewSUBARU storage ring providing an electron beam with energy of 1 GeV, and 17.6 MeV γ ray will be generated through a head-on collision of the electron beam and a 1.064 μm laser light. γ ray flux about the present experiment is predicted theoretically. A planned scheme for promoting the flux is also introduced, As well as the maximum laser power available for the storage ring is discussed.