High-speed processing in wired-and-wireless integrated autonomous decentralized system and its application to IC card ticket system

The automatic fare collection systems need both high performance and high reliability. High performance is one of the most expected functions on the automatic fare collection gates (AFCGs) handling the highly dense passengers during rush hours. Reliability is also indispensable because the tickets are equivalent to money. For a wireless IC card ticket system, expected to improve the passengers’ convenience and to reduce the maintenance cost, is difficult to meet these two requirements because of wireless communications between an IC card and an AFCG. This paper introduces the autonomous decentralized system as the solution and how it is applied to the system. Then, two models are prepared and simulated to evaluate the efficiency, especially high-speed processing. The technologies are implemented into the “Suica” system at East Japan Railway Company and have proven the effectiveness.     

In-Situ Measurement of Supply-Noise Maps With Millivolt Accuracy and Nanosecond-Order Time Resolution

An in situ measurement scheme for generating supply-noise maps, which can be conducted while running applications in product-level LSIs, was developed. The design of the on-chip voltage sampling probe is based on a simple ring oscillator, which converts local supply difference between VDD and V_SS to oscillation-frequency deviation. High measurement accuracy is achieved by off-chip digital signal processing and calibration. This scheme was used to successfully measure 69-mV local supply noise with 5-ns time resolution in a 3G-cellular-phone processor. It will thus help in designing power-supply networks and in visually verifying the quality of a power supply     

Macromolecular complexes of the main storage protein of Vicia faba seeds with sulfated polysaccharide

Specific interaction between legumin from Vicia faba seeds and kappa carrageenan at neutral pH (7.3) and low ionic strength (0.01) and the mechanism that leads to increased conformation stability and a decreased aggregation of the protein by addition of the polysaccharide were investigated using high sensitivity differential scanning calorimetry (DSC), circular dichroism (CD), fluorescence (FLU), the size exclusion chromatography equipped with an online multi-angle light scattering detector (SEC-MALS), turbidimetry and a methylene blue spectrophotometric methods (MBS). Kappa carrageenan (kCG) molecules are able to form with legumin at room temperature a water soluble interpolymeric complex. Complex formation leads to a small perturbation and loosening of the secondary structure of the protein. On the contrary, conformation stability and the stability of the protein molecules with respect to thermo aggregation are noticeably increased. It also reduces the extent of thermal modification of secondary and tertiary structure of legumin due to growth of the net charge of a protein and weakening interaction between similar protein molecules. The joint analysis of SEC-MALS and MBS shown the process is proceeded with a high the degree of conversion (>0.8) and the complexes formed are equimolar.     

Fabrication and optical characterization of vanadium oxide nano-particulates thin film

We have succeeded to fabricate the thin films (350 nm in total thickness) consisting of semiconducting Vanadium-oxide (VO_0.9+x (0.30≦x < 0.37)) nano-particles with 3.47 nm in averaged diameter by using the combined magnetron sputtering and gas aggregation methods. The optical band gap of the film is evaluated as 3.88 eV under the ad hoc assumption of direct allowed optical transition mode by spectroscopic ellipsometry. This value is expanded by 0.18 eV comparing with the estimated VO bulk value. The widening of band gap might be due to the lattice strain and/or the quantum confinement effect of the composed nano-particles.     

Effect of fermented papaya preparation on dermal and intestinal mucosal immunity and allergic inflammations

BACKGROUND: Fermented papaya preparation (FPP) from yeast fermentation of Carica papaya Linn is a natural health food that is commercially sold in Japan. A previous study revealed that FPP has antioxidant activity. However, the effect of FPP on allergic diseases remains unclear. The aim of the present work was to examine whether the oral administration of FPP to mice restrained two types of contact hypersensitivity models, FITC (Th2 type) induced ear and colon oedema, and oxazolone (Th1 type) induced ear and colon oedema. RESULTS: The sensitisation of FITC or oxazolone increased the plasma levels of IL‐10, IFN‐γ, and TNF‐α. Histological examinations revealed a marked increase of IgA, dendritic cells and inflammatory cells in the colon. When the animals were given FPP before sensitisation by FITC or oxazolone, all the events induced by either FITC or oxazolone decreased markedly. CONCLUSION: These results suggest that the oral administration of the FPP may have a therapeutic potential for the prevention of contact hypersensitive immuno‐response. Copyright © 2008 Society of Chemical Industry     

Anhydrous proton-conducting electrolyte membranes based on hyperbranched polymer with phosphonic acid groups for high-temperature fuel cells

The two different molecular weight hyperbranched polymers (HBP(L)-PA-Ac and HBP(H)-PA-Ac) with both phosphonic acid group as a functional group and acryloyl group as a cross-linker at the chain ends were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked electrolyte membranes (CL-HBP-PA) were prepared by their thermal polymerizations using benzoyl peroxide and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the low molecular weight CL-HBP(L)-PA membrane and the high molecular weight CL-HBP(H)-PA membrane were found to be 1.2 × 10⁻⁵ and 2.6 × 10⁻⁶ S cm⁻¹, respectively, at 150 °C under dry condition, and showed the Vogel–Tamman–Fulcher (VTF) type temperature dependence. Both membranes were thermally stable up to 300 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurements using a single membrane electrode assembly cell with both cross-linked membranes were successfully performed.     

Energy conversion efficiency of a welded Cu/Bi–Te/Cu composite under periodically alternating temperature gradients

It was reported recently by us that the energy conversion efficiency η_ATG of thermoelectric (TE) generators working under the alternating temperature gradient (ATG) produced by switching at an optimum period of τ = 120 or 240 s is several times higher than η_STG of them operating under the steady temperature gradient (STG), where the generators are sandwiched between two Peltier modules. However, the reason for η_ATG > η_STG has not yet been explained explicitly. In order to clarify the relation between the optimum τ and η_ATG or η_ATG/η_STG in the wide range of τ, long p- and n-type Cu/Bi–Te/Cu composites with t_Bi–Te = 4.0 mm and t_Cu = 5.0 mm were fabricated so that they have an optimum τ longer than the previous periods. The maxima η_ATG of the p- and n-type composites were 0.073% at τ = 960 s and 0.057% at τ = 480 s, respectively, and their η_ATG/η_STG were approximately 1.4. Owing to this experimental result, η_ATG/η_STG is related closely to the thermal diffusion time τ_D of a composite or a generator, so that η_ATG and η_ATG/η_STG were found to be in inverse proportion to τ_D. The reason for this low η_ATG results from the high external resistance and the long τ caused by a thick t_Bi–Te, in addition to too fat Bi–Te sample giving the high thermal conductance. The maximum η_ATG was also found to be expressed successfully by a theoretical expression.     

Silicon microoptical mirrors to make close parallel beams with conventional laser diodes

We have fabricated two kinds of silicon microoptical mirrors to make optical axes of two high-power laser diodes close at an interval of 100 /spl mu/m, utilizing anisotropic etching of silicon with the self-alignment mask. One of them is a microrectangular prism mirror (MRPM). It has two orthogonal reflection mirrors, composed of polished [110] and anisotropically etched (111) planes of silicon. The other is a micro two-reflection mirror (MTRM). It has two pairs of two reflectors facing each other in parallel. The use of MTRM made the mounting process easier than that of MRPM. The use of the self-alignment mask made mirror surface smoother and it has been confirmed that full widths at half maximum (FWHM) are almost the same with and without reflections by MRPM or MTRM, respectively. It has also been shown that the etched (111) plane has the etching-condition dependence of surface roughness.