Shibaura Institute of Technology

Abstract The spectral ratio between horizontal and vertical components (H/V ratio) of microtremors measured at the ground surface has been used to estimate fundamental periods and amplification factors of a site, although this technique lacks theoretical background. The aim of this article is to formulate the H/V technique in terms of the characteristics of Rayleigh and Love waves, and to contribute to improve the technique. The improvement includes use of not only peaks but also troughs in the H/V ratio for reliable estimation of the period and use of a newly proposed smoothing function for better estimation of the amplification factor. The formulation leads to a simple formula for the amplification factor expressed with the H/V ratio. With microtremor data measured at 546 junior high schools in 23 wards of Tokyo, the improved technique is applied to mapping site periods and amplification factors in the area.

Impedance spectroscopy was applied to investigate the characteristics of dye-sensitized nanostructured TiO2 solar cells (DSC) with high efficiencies of light to electricity conversion of 11.1% and 10.2%. The different parameters, that is, chemical capacitance, steady-state transport resistance, transient diffusion coefficient, and charge-transfer (recombination) resistance, have been interpreted in a unified and consistent framework, in which an exponential distribution of the localized states in the TiO2 band gap plays a central role. The temperature variation of the chemical diffusion coefficient dependence on the Fermi-level position has been observed consistently with the standard multiple trapping model of electron transport in disordered semiconductors. A Tafel dependence of the recombination resistance dependence on bias potential has been rationalized in terms of the charge transfer from a distribution of surface states using the Marcus model of electron transfer. The current-potential curve of the solar cells has been independently constructed from the impedance parameters, allowing a separate analysis of the contribution of different resistive processes to the overall conversion efficiency.

Climate change and the urgency of decarbonizing the built environment are driving technological innovation in the way we deliver thermal comfort to occupants. These changes, in turn, seem to be setting the directions for contemporary thermal comfort research. This article presents a literature review of major changes, developments, and trends in the field of thermal comfort research over the last 20 years. One of the main paradigm shift was the fundamental conceptual reorientation that has taken place in thermal comfort thinking over the last 20 years; a shift away from the physically based determinism of Fanger's comfort model toward the mainstream and acceptance of the adaptive comfort model. Another noticeable shift has been from the undesirable toward the desirable qualities of air movement. Additionally, sophisticated models covering the physics and physiology of the human body were developed, driven by the continuous challenge to model thermal comfort at the same anatomical resolution and to combine these localized signals into a coherent, global thermal perception. Finally, the demand for ever increasing building energy efficiency is pushing technological innovation in the way we deliver comfortable indoor environments. These trends, in turn, continue setting the directions for contemporary thermal comfort research for the next decades.

Using the ``modified DPMJET-III'' model explained in the previous paper [T. Sanuki et al., preceding Article, Phys. Rev. D 75, 043005 (2007).], we calculate the atmospheric neutrino flux. The calculation scheme is almost the same as HKKM04 [M. Honda, T. Kajita, K. Kasahara, and S. Midorikawa, Phys. Rev. D 70, 043008 (2004).], but the usage of the ``virtual detector'' is improved to reduce the error due to it. Then we study the uncertainty of the calculated atmospheric neutrino flux summarizing the uncertainties of individual components of the simulation. The uncertainty of $K$-production in the interaction model is estimated using other interaction models: FLUKA'97 and FRITIOF 7.02, and modifying them so that they also reproduce the atmospheric muon flux data correctly. The uncertainties of the flux ratio and zenith angle dependence of the atmospheric neutrino flux are also studied.

Reproducible switching of the polymorph-dependent excited-state intramolecular proton-transfer (ESIPT) luminescence of an imidazo[1,2-a]pyridine between blue-green and yellow (see picture) is achieved by thermal control of its solid-state molecular packing. Thus, ESIPT is a promising mechanism for packing-to-luminescence transduction and amplification that offers a novel design concept for tunable organic luminescent solids.

A novel thiocyanate-free cyclometalleted ruthenium sensitizer for solar cells is designed and developed. Upon anchoring to nanocrystalline TiO(2) films, it exhibits a remarkable incident monochromatic photon-to-current conversion efficiency of 83%. The solar cell employing a liquid-based electrolyte exhibits a short circuit photocurrent density of 17 mA/cm(2), an open circuit voltage of 800 mV, and a fill factor of 0.74, corresponding to an overall conversion efficiency of 10.1% at standard AM 1.5 sunlight. To understand the structural, electronic, and optical properties of the cyclometalleted ruthenium sensitizer, we have investigated using density functional theory (DFT) and time-dependent DFT (TDDFT). Our results show the HOMO is located mostly on ruthenium and cyclometalated ligand, while the LUMO is on 4-carboxylic acid-4'-carboxylate-2,2'-bipyridine. Molecular orbitals analysis confirmed the experimental assignment of redox potentials, and TDDFT calculations allowed assignment of the visible absorption bands. The present findings provide new design criteria for the next generation of ruthenium sensitizers and help foster widespread interest in the engineering of new sensitizers that interact effectively with the I(-)/I(3)(-) redox couple.

In recent years, there has been major interest in the exposure to physical therapy during rehabilitation. Several publications have demonstrated its usefulness in clinical/medical and human machine interface (HMI) applications. An automated system will guide the user to perform the training during rehabilitation independently. Advances in engineering have extended electromyography (EMG) beyond the traditional diagnostic applications to also include applications in diverse areas such as movement analysis. This paper gives an overview of the numerous methods available to recognize motion patterns of EMG signals for both isotonic and isometric contractions. Various signal analysis methods are compared by illustrating their applicability in real-time settings. This paper will be of interest to researchers who would like to select the most appropriate methodology in classifying motion patterns, especially during different types of contractions. For feature extraction, the probability density function (PDF) of EMG signals will be the main interest of this study. Following that, a brief explanation of the different methods for pre-processing, feature extraction and classifying EMG signals will be compared in terms of their performance. The crux of this paper is to review the most recent developments and research studies related to the issues mentioned above.

ABSTRACT Global-scale 21st-century glacier mass change projections from six published global glacier models are systematically compared as part of the Glacier Model Intercomparison Project. In total 214 projections of annual glacier mass and area forced by 25 General Circulation Models (GCMs) and four Representative Concentration Pathways (RCP) emission scenarios and aggregated into 19 glacier regions are considered. Global mass loss of all glaciers (outside the Antarctic and Greenland ice sheets) by 2100 relative to 2015 averaged over all model runs varies from 18 ± 7% (RCP2.6) to 36 ± 11% (RCP8.5) corresponding to 94 ± 25 and 200 ± 44 mm sea-level equivalent (SLE), respectively. Regional relative mass changes by 2100 correlate linearly with relative area changes. For RCP8.5 three models project global rates of mass loss (multi-GCM means) of >3 mm SLE per year towards the end of the century. Projections vary considerably between regions, and also among the glacier models. Global glacier mass changes per degree global air temperature rise tend to increase with more pronounced warming indicating that mass-balance sensitivities to temperature change are not constant. Differences in glacier mass projections among the models are attributed to differences in model physics, calibration and downscaling procedures, initial ice volumes and varying ensembles of forcing GCMs.

Silver nanoparticles (AgNPs) have been employed in various fields of biotechnology due to their proven properties as an antibacterial, antiviral and antifungal agent. AgNPs are generally synthesized through chemical, physical and biological approaches involving a myriad of methods. As each approach confers unique advantages and challenges, a trends analysis of literature for the AgNPs synthesis using different types of synthesis were also reviewed through a bibliometric approach. A sum of 10,278 publications were analyzed on the annual numbers of publication relating to AgNPs and biological, chemical or physical synthesis from 2010 to 2020 using Microsoft Excel applied to the Scopus publication database. Furthermore, another bibliometric clustering and mapping software were used to study the occurrences of author keywords on the biomedical applications of biosynthesized AgNPs and a total collection of 224 documents were found, sourced from articles, reviews, book chapters, conference papers and reviews. AgNPs provides an excellent, dependable, and effective solution for seven major concerns: as antibacterial, antiviral, anticancer, bone healing, bone cement, dental applications and wound healing. In recent years, AgNPs have been employed in biomedical sector due to their antibacterial, antiviral and anticancer properties. This review discussed on the types of synthesis, how AgNPs are characterized and their applications in biomedical field.

Abstract The hypotheses that a firm's environmental performance has a positive impact on its financial performance and vice versa are statistically supported by Japanese data. However, this tendency for two‐way positive interaction appears to be only a relatively recent phenomenon. The tendency for realizing the two‐way interaction is not limited to the top‐scoring firms in terms of both financial and environmental performance. On the contrary, this is also a trend that can be observed fairly generally. Obviously, when we consider only scores of those companies that published the relevant information in their environmental reports, and conduct the statistical causality test with such information as additional input to the pooled time‐series and cross‐section data of financial performance, the results become more strongly significant. From the recent experience of environmental policies in Japan, we infer that information‐based environmental policy measures are effective to encourage the ongoing transition toward a more sustainable market economy. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.

A magneto-optical isolator is demonstrated for use with a Si waveguide. The isolator is based on a Mach–Zehnder interferometer employing a nonreciprocal phase shift and is fabricated by bonding a magneto-optic garnet CeY2Fe5O12 (Ce:YIG) directly onto the Si waveguide. The surface-activated bonding is based on oxygen-plasma exposure in a high-vacuum chamber. The nonreciprocal phase shift is observed by applying an external magnetic field. An isolation ratio of 21dB is obtained at a wavelength of 1559nm.

Control of nonlinear systems preceded by unknown hysteresis nonlinearities is a challenging task and has received increasing attention in recent years due to growing industrial demands involving varied applications. In the literature, many mathematical models have been proposed to describe the hysteresis nonlinearities. The challenge addressed here is how to fuse those hysteresis models with available robust control techniques to have the basic requirement of stability of the system. The purpose of the note is to show such a possibility by using the Prandtl-Ishlinskii (PI) hysteresis model. An adaptive variable structure control approach, serving as an illustration, is fused with the PI model without necessarily constructing a hysteresis inverse. The global stability of the system and tracking a desired trajectory to a certain precision are achieved. Simulation results attained for a nonlinear system are presented to illustrate and further validate the effectiveness of the proposed approach.

In order to verify whether brain damage caused by chronic oxidative stress induces the impairment of cognitive function, the ability of learning and memory was assessed using the water maze and the eight-arm radial maze tasks. Young rats showed significantly greater learning ability before the stress than the old and vitamin E-deficient rats. At five days after subjection to oxidative stress, the memory function of the young declined toward the level of that in the aged rats maintained under normal condition. This phenomenon is supported by the findings that the delayed-type apoptosis appeared in the CA1 region of the hippocampus of the young at five to seven days after the stress. Vitamin E supplementation to the young accelerated significantly their learning functions before the stress and prevented the deficit of memory caused by the stress. When rats were subjected to stress, thiobarbituric acid-reactive substance (TBARS), lipid hydroperoxides, and protein carbonyls were significantly increased in synaptic plasma membranes. It was found that zeta-potential of the synaptic membrane surface was remarkably decreased. These phenomena were also observed in the aged and vitamin E-deficient rats maintained under normal condition. These results suggest that oxidative damage to the rat synapse in the cerebral cortex and hippocampus during aging may contribute to the deficit of cognitive functions.

The 2016 oxide electronic materials and oxide interfaces roadmap, Lorenz, M, Ramachandra Rao, M S, Venkatesan, T, Fortunato, E, Barquinha, P, Branquinho, R, Salgueiro, D, Martins, R, Carlos, E, Liu, A, Shan, F K, Grundmann, M, Boschker, H, Mukherjee, J, Priyadarshini, M, DasGupta, N, Rogers, D J, Teherani, F H, Sandana, E V, Bove, P, Rietwyk, K, Zaban, A, Veziridis, A, Weidenkaff, A, Muralidhar, M, Murakami, M, Abel, S, Fompeyrine, J, Zuniga-Perez, J, Ramesh, R, Spaldin, N A, Ostanin, S, Borisov, V, Mertig, I, Lazenka, V, Srinivasan, G, Prellier, W, Uchida, M, Kawasaki, M, Pentcheva, R, Gegenwart, P, Miletto Granozio, F, Fontcuberta, J, Pryds, N

To elucidate the influence of oxidative stress on the brain functions during aging, the cognitive performance ability of rats was assessed by using the water-maze test as an oxidative stress before and after hyperoxia. Young rats showed significantly greater learning ability than both old rats and vitamin-E-deficient rats. Although the memory functions of all rats were Impaired after oxidative stress, the memory retention of young rats was greater than those of other groups. After the stress, none of the rats recovered their learning ability. During aging and through hyperoxia, the release of acetylcholine from nerve terminals was remarkably decreased. Instead, thiobarbituric acid reactive substance (TBARS) contents in rat hippocampus and cebral cortex, and their synaptic membranes, were significantly increased during aging and by oxidative stress. The antioxidative defense system in rat brain was also changed by the stress. These results suggest that oxidative stress may contribute to learning and memory deficits following oxidative brain damage during aging.

Since the inhibitory effect of eugenol (a), which was isolated as an antioxidative component from plant, Caryopylli flos, on lipid peroxidation was less than that of alpha-tocopherol, we synthesized the eugenol-related compounds dieugenol (b), tetrahydrodieugenol (c), and dihydroeugenol (d), to find new strong antioxidants and assessed them for their inhibitory effect on lipid peroxidation and scavenging ability for superoxide and hydroxyl radicals. The antioxidative activities were in the order: (b)>(c)>(d)>(a) for the thiobarbituric acid reactive substance (TBARS) formation. These results suggest that the dimerized compounds have higher antioxidant activities than that of the monomers. Electron spin resonance (ESR) spin trapping experiments revealed that eugenol and its dimer, having allyl groups in the structure, scavenged superoxide, and that only eugenol trapped hydroxyl radicals under the conditions used. These finding suggest that eugenol and dieugenol have a different mechanism of antioxidation, i.e. eugenol may inhibit lipid peroxidation at the level of initiation, however, the related dimeric compounds may inhibit lipid peroxidation at the level of propagation of free radical chain reaction like alpha-tocopherol.

EMTP has been widely used in Japan to analyze switching and lightning overvoltages to design power stations and substations from the viewpoint of insulation coordination. The Japanese standard of high voltage testing, JEC-0102-1994, and the insulation design and the coordination of an 1100-kV line of Tokyo Electric Power Company were mostly based on EMTP simulations. This paper presents a method of a lightning surge analysis using the EMTP recommended in the Japanese standard and related guidelines, and suggests further work to be done based on discussions of applicable limits and problems of the recommended models.

We develop a new spectral model for the broad-band spectral energy distribution (SED) of active galactic nuclei (AGN). This includes an outer standard disc, an inner warm Comptonizing region to produce the soft X-ray excess and a hot corona. We tie these together energetically by assuming Novikov–Thorne emissivity, and use this to define a size scale for the hard X-ray corona as equal to the radius where the remaining accretion energy down to the black hole can power the observed X-ray emission. We test this on three AGN with well-defined SEDs as well as on larger samples to show that the average hard X-ray luminosity is always approximately a few per cent of the Eddington luminosity across a large range of Eddington ratio. As a consequence, the radial size scale required for gravity to power the X-ray corona has to decrease with increasing Eddington fraction. For the first time, we hardwire this into the spectral models, and set the hard X-ray spectral index self-consistently from the ratio of the hard X-ray luminosity to intercepted seed photon luminosity from the disc. This matches the observed correlation of steeper spectral index with increasing Eddington ratio, as well as reproducing the observed tight UV/X relation of quasars. We also include the reprocessed emission produced by the hot inner flow illuminating the warm Comptonization and standard disc regions and show that this predicts a decreasing amount of optical variability with increasing Eddington ratio as observed, though additional processes may also be required to explain the observed optical variability.

We demonstrated single-shot measurements of spectral interference between a white-light continuum generated in a hollow-fiber and its second harmonic. The interference has information on the carrier-envelope phase of an input pulse to the fiber and the time delay of the blue wing of the continuum. By analyzing the observed spectral interference, we estimated shot-by-shot changes of the carrier-envelope phase. This method is useful for determining the carrier-envelope phase changes of a low-repetition-rate, high-intensity laser.

Estimates of future flood risk rely on projections from climate models. The relatively few climate models used to analyze future flood risk cannot easily quantify of their associated uncertainties. In this study, we demonstrated that the projected fluvial flood changes estimated by a new generation of climate models, the collectively known as Coupled Model Intercomparison Project Phase 6 (CMIP6), are similar to those estimated by CMIP5. The spatial patterns of the multi-model median signs of change (+ or -) were also very consistent, implying greater confidence in the projections. The model spread changed little over the course of model development, suggesting irreducibility of the model spread due to internal climate variability, and the consistent projections of models from the same institute suggest the potential to reduce uncertainties caused by model differences. Potential global exposure to flooding is projected to be proportional to the degree of warming, and a greater threat is anticipated as populations increase, demonstrating the need for immediate decisions.