Multi-vector feature space based on pseudo-Euclidean space and oblique basis

The Earth Mover’s Distance (EMD) and the quadratic-form distance (QFD) are representative distances used in similarity searches of images. Although the QFD greatly outperforms the EMD in speed, the EMD outperform the QFD in performance. The EMD, however, has almost no theoretical justification and requires high computation costs. We propose a feature space model we call a “multi-vector feature space based on pseudo-Euclidean space and an oblique basis (MVPO).” In MVPO, an object such as an image is represented by a vector set (roughly speaking, a solid) and the EMD is reinterpreted as the distance between vector sets while the QFD is reinterpreted as the distance between the centroids of vector sets. Therefore MVPO gives a common geometrical view to these distances. We hypothesized that in MVPO the entity of an image is represented by a vector set (solid) and geometrical reasoning is applicable to MVPO. Our hypothesis explains well that the EMD outperforms the QFD in performance because the centroid of a solid is the simplest approximation of it. Our hypothesis implies that the performance of the QFD should be good when solids are far apart but bad when they are close together. We conjectured that discriminability would decline—that is, dissimilar images would be judged to be similar—when the centroids of solids are very close. Our experiment supported this conjecture. And from our hypothesis we conjectured that by making an original solid simpler, we can make an approximation method that has better performance than the QFD and faster than the EMD. The results of our experiment with this method supported our conjecture and consequently our hypothesis.

High-temperature strengths of aluminium composite reinforced with continuous SiC fibre

Aluminium alloys were reinforced unidirectionally with 30, 35, 40 and 50 vol %SiC fibres by a liquid-pressing method. The SiC fibres for reinforcement were produced from a polycarbosilane and were yarns consisting of 500 continuous filaments of length 300 m and diameter 13m, having a tensile strength of 2000 MPa. High-temperature tensile and bending strengths of the composites were examined in air in the temperature range from room temperature to 500° C. The strengths were not influenced by temperature up to 400° C, but were decreased at 500° C. The decrease is considered to be caused by the reduction in transfer efficiency of the stress accompanying the decrease in adhesion between fibres and matrix.     

A simple test method,NAL-II,to evaluate the strength and elastic modulus of polymer matrix composite laminates

This study proposes and assesses a simple test method (NAL-II) to evaluate compressive properties of carbon fiber-reinforced polymer matrix composite laminates (CFRP). Compressive tests based on ASTM D6641 and NAL-II methods were conducted for direct comparison using three kinds of quasi-isotropic composite laminates (T800H/3633, T800S/3900-2B, and IM600/133). Stress–strain curves including the compressive modulus obtained using the NAL-II method showed good agreement with those obtained using the ASTM D6641. The NAL-II method gave slightly higher (approximately 10%) compressive strengths than the ASTM D6641 method, probably because of suppression of bending (buckling) before failure. The experimentally obtained results suggest that the NAL-II method can be useful for international standard testing of the non-hole compressive strength of CFRP laminates.     

Synthesis and polymerization of nucleic acid base substituted L-lysine

Summary Poly-l-lysines containing nucleic acid bases, that is, adenine, thymine, uracil and theophylline were synthesized. The nucleic acid base substituted l-lysine derivatives were prepared from ,N-Cbz-l-lysine and the p-nitrophenyl esters of the carboxyethyl derivatives of the nucleic acid bases. The polymers were obtained from these l-lysine derivatives by the NCA method.     

Chemical sensing plate with a laser-terahertz monitoring system

A new type of laser-terahertz emission system for noncontact investigations of chemical solutions has been developed. The system monitors terahertz emission from a sensing plate, which consists of silicon oxide and silicon thin film layers on a sapphire substrate. Sensing of chemical solutions with pH values between 1.68 and 10.01 was demonstrated. The amplitude of the terahertz emission from the sensing plate increased with increasing pH value. This change in the amplitude was caused by a change in the depletion layers of the silicon thin film when protons were adsorbed on the surface of the sensing plate. This study demonstrates that full noncontact monitoring of chemical solutions is possible using the laser-terahertz emission system.     

Reconnaissance report on geotechnical damage caused by 2018 Hokkaido Eastern Iburi earthquake with JMA seismic intensity 7

The 2018 Hokkaido Eastern Iburi earthquake with the JMA seismic intensity of 7 occurred at a central south part of Hokkaido, Japan at 3:08 a.m. on September 6, 2018. Considering the social importance of this historical earthquake-induced geo-disaster, the Japanese Geotechnical Society (JGS) organized a “JGS Survey Team for Geotechnical Disasters in Hokkaido, Japan Induced by the 2018 Hokkaido Eastern Iburi earthquake,” mainly comprised of experts from the industry and academia of the Hokkaido branch of JGS. The aim of the survey team was to investigate the phenomena and factors which contributed to disaster recovery and disaster prevention/mitigation from both short- and mid- to long-term perspectives, and to provide academic advice to related government organizations. Based on the results of the site investigations conducted by the JGS survey team (JGS, 2019), this report provides a summary of the geotechnical damage caused by 2018 Hokkaido Eastern Iburi earthquake by presenting the detail of strong seismic motion and a various types of geo-disasters which occurred due to the earthquake. Furthermore, this report highlights future research issues on disaster prevention/mitigation in Hokkaido considering the features of the geo-disasters attributed to the earthquake.     

Wave-optical evaluation of interference fringes and wavefront phase in a hard-x-ray beam totally reflected by mirror optics

The intensity flatness and wavefront shape in a coherent hard-x-ray beam totally reflected by flat mirrors that have surface bumps modeled by Gaussian functions were investigated by use of a wave-optical simulation code. Simulated results revealed the necessity for peak-to-valley height accuracy of better than 1 nm at a lateral resolution near 0.1 mm to remove high-contrast interference fringes and appreciable wavefront phase errors. Three mirrors that had different surface qualities were tested at the 1 km-long beam line at the SPring-8/Japan Synchrotron Radiation Research Institute. Interference fringes faded when the surface figure was corrected below the subnanometer level to a spatial resolution close to 0.1 mm, as indicated by the simulated results.     

Patch Plate Repair Method for Steel Structures Combining Adhesives and Stud Bolts

International Journal of Steel Structures - Recently, a repair method by bonding patch plates is being applied to corroded steel structures. However, one of the issues of patch plate bonding repair...     

Mechanical activation of TiFe for hydrogen storage by cold rolling under inert atmosphere

TiFe is a very interesting material for hydrogen storage in the solid state, due to its hydrogen capacity of 1.9 wt % and to the fact it can be absorb/desorb hydrogen at room temperature. However, the TiFe produced by casting does not absorb hydrogen, unless a procedure called activation is applied, which is based on a repetition of several thermal cycles. This study evaluates the effects of a mechanical activation route for the TiFe intermetallic compound, namely, cold rolling (CR) under inert atmosphere. Stoichiometric TiFe was prepared from elementary powders by arc melting. Ingot was grinded and then cold rolled for 20 and 40 passes under argon inside a glove box, with moisture and oxygen contents below 0.1 ppm. Cold rolled samples consisted of two parts: powder particles and thin cracked flakes. The results showed that mechanically activated samples by CR exhibited rapid absorption of hydrogen at room temperature, without using a thermal activation process. In general, the average storage capacity of hydrogen was 1.4 wt% H₂ for the first absorption, regardless of the number of passes for both flake and powder samples.     

Tubulin-Based Nanotubes as Delivery Platform for Microtubule-Targeting Agents

Tubulin-based nanotubes (TNTs) to deliver microtubule-targeting agents (MTAs) for clinical oncology are reported. Three MTAs, docetaxel (DTX), laulimalide (LMD), and monomethyl auristatin E (MMAE), which attach to different binding sites in a tubulin, are loaded onto TNTs and cause structural changes in them, including shape anisotropy and tubulin layering. This drug-driven carrier transformation leads to changes in the drug-loading efficiency and stability characteristics of the carrier. TNTs coloaded with DTX and LMD efficiently deliver dual drug cargoes to cellular tubulins by the endolysosomal pathway, and results in synergistic anticancer and antiangiogenic action of the drugs in vitro. In in vivo tests, TNTs loaded with a microtubule-destabilizing agent MMAE suppress the growth of tumors with much higher efficacy than free MMAE did. This work suggests a new concept of using a drug's target protein as a carrier. The findings demonstrate that the TNTs developed here can be used universally as a delivery platform for many MTAs.