Thick Nb-Doped Bismuth Titanate Film with Controllable Grain Orientation

In the current work, we reported a potential approach to obtain thick ceramic films with controllable grain orientation based on magnetic alignment and polymerization techniques. The slurry containing 40 vol% Bi₄Ti_2.96Nb_0.04O₁₂ (BINT) ceramic powder, monomer, initiator, and catalyst was drop coated on a Pt substrate and then moved into a vertical 10 T magnetic field. In 1–2 min, the ceramic particles were aligned by a strong magnetic force in slurry and then in situ locked by polymerization on the substrate. After sintering at 1000°C, a BINT ceramic film (50–80 μm in thickness) with a highly a / b plane orientation was obtained. Theoretically, the grain orientation in the films can be easily controlled by adjusting the magnetic field direction. This approach is readily applicable to other materials with a non-cubic structure and is expected to facilitate the fast preparation of grain-oriented thick films.     

Simultaneous particulate design of primary and agglomerated crystals of steroid by spherical agglomeration in liquid for dry powder inhalation

Spherical agglomerates of steroid KSR-592, consisting of fine primary drug crystals suitable for dry powder inhalation (DPI), were prepared by the spherical agglomeration method in liquid with a bridging liquid. It was found that the particle size of primary crystals increased until the dispersing medium was saturated with the bridging liquid, whereas the spherical agglomeration of primary crystals was continued even after the saturation of medium with the bridging liquid. The growth rates of primary crystals and agglomerates increased with an increase in the temperature and/or a reduction in the agitation speed of the system. The agglomerates were easily disintegrated into the primary crystals depositing ideally on carrier lactose particles for DPI by mixing. The in vitro efficiency of the mixed system of lactose and disintegrated primary crystals of drug was 2 to 3 times higher than that of crystals prepared conventionally. Furthermore, the soft agglomerates disintegrated easily into respirable particles in air stream when emitted from the inhalation device were prepared by reducing the agitation speed after the dispersing medium was saturated with the bridging liquid.     

Posture estimation of hose-shaped robot by using active microphone array

Hose-shaped rescue robots have been developed for searching narrow spaces such as under collapsed buildings. The posture estimation independent of the past history is critical, because conventional inertial-sensor-based posture estimation has two main problems; a cumulative error problem peculiar to inertial sensors, and a sudden posture change problem caused by external forces. For coping with the two problems, we developed a novel posture estimation method by putting an active microphone array, a set of microphones and loudspeakers, on the robot. The method calculates the time difference of arrival (TDOA) of the reference signal emitted from one loudspeaker, and estimates the posture from the distance obtained by TDOA. This concise method still has three problems: (1) external noise, (2) reverberation and reflection, and (3) obstacles. These problems are tackled by (1) TSP signal, (2) GCC-PHAT and a threshold-based onset detection, and (3) rejecting incorrect onset times, respectively. Experiments with simulated sounds and actual recordings demonstrate that the method attains the performance of estimation comparable to that of conventional methods, that is, less than 20 cm of the tip position error. Even without historical data, the method attains the similar performance while conventional methods fail.     

Towards Management of Future Networks and Services: A Report on IEEE/IFIP NOMS 2010

The 12th IEEE/IFIP Network Operations and Management Symposium (NOMS 2010) was held on April 19–23, 2010 in Osaka, Japan. Since 1988, NOMS, which has been held in even-numbered years, has been the primary forum for technical exchange among all constituencies in network and service management, including the research, vendor, standards, development, systems integration, service provider, user communities, and many others.     

Simulation of drop deposition process in annular mist flow using three-dimensional particle method

The three-dimensional moving particle semi-implicit (MPS) method is employed to simulate the deposition process of single droplet on the liquid film. The model accounts for the presence of inertial, gravitation, viscous and surface tension and is validated by comparison with experimental results. The parameters of liquid droplets and film are calculated by a one-dimensional mixture model in which correlations and methods on void fraction, entrainment fraction and droplet velocity and size distribution are employed. The simulation results are analyzed to study the effect of splash on the deposition and re-entrainment processes in annular-mist flow. It is found that splash plays an important role in the deposition and re-entrainment processes in high quality conditions of BWR.     

Effects of Pb Intercalation on the Structural and Electronic Properties of Epitaxial Graphene on SiC

The effects of Pb intercalation on the structural and electronic properties of epitaxial single‐layer graphene grown on SiC(0001) substrate are investigated using scanning tunneling microscopy (STM), noncontact atomic force microscopy, Kelvin probe force microscopy (KPFM), X‐ray photoelectron spectroscopy, and angle‐resolved photoemission spectroscopy (ARPES) methods. The STM results show the formation of an ordered moiré superstructure pattern induced by Pb atom intercalation underneath the graphene layer. ARPES measurements reveal the presence of two additional linearly dispersing π‐bands, providing evidence for the decoupling of the buffer layer from the underlying SiC substrate. Upon Pb intercalation, the Si 2p core level spectra show a signature for the existence of Pb? Si chemical bonds at the interface region, as manifested in a shift of 1.2 eV of the bulk SiC component toward lower binding energies. The Pb intercalation gives rise to hole‐doping of graphene and results in a shift of the Dirac point energy by about 0.1 eV above the Fermi level, as revealed by the ARPES measurements. The KPFM experiments have shown that decoupling of the graphene layer by Pb intercalation is accompanied by a work function increase. The observed increase in the work function is attributed to the suppression of the electron transfer from the SiC substrate to the graphene layer. The Pb intercalated structure is found to be stable in ambient conditions and at high temperatures up to 1250 °C. These results demonstrate that the construction of a graphene‐capped Pb/SiC system offers a possibility of tuning the graphene electronic properties and exploring intriguing physical properties such as superconductivity and spintronics.     

Change in the fractal dimension of the grain boundaries in pure Zn polycrystals during creep

The effects of creep deformation on the shape of grain boundaries were investigated on pure Zn polycrystals at 373 K. The fractal dimension of the grain boundaries D(1D2) was estimated by the box-counting method. There was then discussion on the relationship between the value of D, the microstructures, and the creep or plastic strain in the deformed specimens of metallic materials.The fractal dimension of the grain boundaries (D) increased with increasing the creep strain in pure Zn polycrystals, but the increase in the value of D levelled off when the creep strain exceeded about 0.30. The value of D decreased as the creep stress decreased. The increase in the value of D with the creep strain was correlated with the increase in the density of slip lines in the grains that formed the ledges and steps on grain boundaries. The value of D on the plane in parallel with the tensile axis was slightly larger than that on the plane transverse to the tensile axis. The mean shear strain on grain boundaries estimated from the value of D was correlated with the creep or plastic strain in the deformed specimens.     

Fabrication of Stable Al2O3 Slurries and Dense Green Bodies Using Wet Jet Milling

A wet jet milling process was used as a novel method to prepare Al₂O₃ slurries. The wet jet-milled slurries showed very low viscosity compared with the ball-milled slurries. Moreover, the viscosity of the wet jet-milled slurries was constant for long times, whereas that of the ball-milled slurries increased rapidly with time. Al₂O₃ particles after wet jet milling retained initial surface conditions, although Al₂O₃ particles after ball milling yielded more OH groups on the surface. Casting rate was sensitive to the solid content and preparation method of slurry. The relative density of the green bodies prepared from the wet jet-milled slurries was about 65% or more and was independent of the slurry solid content. On the other hand, the relative density of the green bodies prepared from the ball-milled slurries increased with increasing solid content and was higher than 60% at the solid content of 50% by volume. Linear shrinkage of the sintered bodies prepared from the wet jet-milled slurries was very low and independent of the solid content of the slurry whereas that of the sintered bodies prepared from the ball-milled slurries increased with decreasing solid content.     

Growth Mechanism of Nanometer-Sized SiC and Oxidation Resistance of SiC-Coated Diamond Particles

Diamond particles were coated with a thin SiC layer by the reaction of SiO vapor with diamond, and the growth mechanism of SiC as well as the oxidation resistance of the SiC-coated diamond were studied. The growth process of the SiC layer can be separated into two steps. In the first step, a thin layer of SiC with a thickness of about 15 nm is formed due to the reaction between SiO vapor and diamond. In the second step, nanometer-sized SiC granules are deposited on the SiC layer by the reaction between SiO vapor and CO. The apparent activation energy for the formation of SiC layer on diamond was found to be 100 kJ/mol. This value suggests that the SiC coating process occurred mainly by vapor-phase reaction. The oxidation resistance of the SiC-coated diamond was improved depending on the thickness of the SiC layer. Oxidation of the SiC-coated diamond particles began at 950°C, which was 400°C higher than that of uncoated diamond.     

Contact-based stiffness sensing of human eye.

Goldmann applanation tonometry is commonly used for measuring intraocular pressure (IOP) to diagnose glaucoma. However, the measured IOP by conventional applanation tonometry is valid only under the assumption that all subjects have the same structural eye stiffness. This paper challenges in vivo measurement of eye stiffness with a noninvasive approach and investigates individual differences of eye stiffness. Eye stiffness is defined by the applied force and displacement of the cornea. The displacement is detected based on captured images by a high resolution camera. The experimental results show that the measured stiffness nicely matches the analytical result that is derived from a simple spherical deformation model with an internal pressure. However, some subjects have different eye stiffness even with the same IOP. IOP with abnormal stiffness may be over/underestimated by conventional applanation tonometry. The proposed eye stiffness measurement can help detect the misestimated eye and it contributes to the early detection of glaucoma.