THE TRANSITON ABOUT TRAFFIC SYSTEM OF BICYCLES

本研究は，自転車の普及や法的整備の歴史から，道路通行システムにおける自転車の位置付けと通行実態の変遷を明らかにすることで，自転車の歩道通行の常態化や双方向通行の要因について一示唆を得ることを目指す．まず，各法制度の変遷から，1970年と1978年の道路交通法改正が自転車の位置付けの変化点であることを明らかにした．次に，1960年から1985年の自転車通行状況を写した写真や映像資料からデータベースを作成し自転車の道路通行実態の変遷を把握した結果，改正前は自転車の車道・左側走行が浸透していたが，1970年の道路交通法改正後に歩道走行が出現し，1978年の道路交通法改正後に車道走行が減少し歩道走行が増加したことがわかった．また，利用目的と道路交通法に基づいた道路通行システムやルールの曖昧さと周知不足が，自転車の歩道通行の常態化や双方向通行の要因である可能性を示唆した．The aim of this study is to understand the transition and the actual condition on the traffic system of bicycles by the spread of bicycles and the change of the legal system, in order to consider the factor that brought the current bicycle traffic situation. As a result, it is cleared that, as a transition about traffic system of bicycles, the revision of the Road Traffic Act in 1970 and 1978 became a point of change in the positioning of bicycles, and it brought the present bicycle traffic situation. To understand the actual condition of bicycle traffic system, a database was built from photograph and video materials during the perion of 1960 to 1985 . The actual condition of the traffic system of the bicycle, the bicycle roadway, bicycling on the left side had penetrated before the revised period, but from the beginning of revision period, bicycling on the sidewalk and on right side of the roadway had appeared. It was revealed that bicycling on the roadway decreased and on the sidewalk increased, as bicycling on the sidewalk was permitted in the second revised period. In addition, the authors suggested that the lack of understanding or discordance with the characteristics of bicyle as avehicle on the bicycle traffic system and rules based on the Road Traffic Act may be factors wich brought the bicycling on the sidewalk and two way running

Single-Channel Speech Enhancement Based on Frequency Domain ALE

In the present paper, a new single-channel speech enhancement system is proposed. The proposed system is based on frequency domain adaptive line enhancer; therefore, it is advantageous to non-stationary environments. Also, frequency domain decorrelation parameters are introduced and then adjusted independently. The performance of the proposed system is examined through computer simulations. The effectiveness of the proposed system is confirmed through computer simulations

Speech Noise Reduction System Based on Frequency Domain ALE Using Windowed Modified DFT Pair

The speech noise reduction system based on the frequency domain adaptive line enhancer using a windowed modified DFT (MDFT) pair is presented. The adaptive line enhancer (ALE) is effective for extracting sinusoidal signals blurred by a broadband noise. In addition, it utilizes only one microphone. Therefore, it is suitable for the realization of speech noise reduction in portable electronic devices. In the ALE, an input signal is generated by delaying a desired signal using the decorrelation parameter, which makes the noise in the input signal decorrelated with that in the desired one. In the present paper, we propose to set decorrelation parameters in the frequency domain and adjust them to optimal values according to the relationship between speech and noise. Such frequency domain decorrelation parameters enable the reduction of the computational complexity of the proposed system. Also, we introduce the window function into MDFT for suppressing spectral leakage. The performance of the proposed noise reduction system is examined through computer simulations

Observing Supernova Neutrino Light Curves with Super-Kamiokande. III. Extraction of Mass and Radius of Neutron Stars from Synthetic Data

Neutrinos are guaranteed to be observable from the next Galactic supernova (SN). Optical light and gravitational waves are also observable, but may be difficult to observe if the location of the SN in the Galaxy or the details of the explosion are unsuitable. The key to observing the next SN is to first use neutrinos to understand various physical quantities and then link them to other signals. In this paper, we present Monte Carlo sampling calculations of neutrino events from Galactic SN explosions observed with Super-Kamiokande. The analytical solution of neutrino emission, which represents the long-term evolution of the neutrino light curve from SNe, is used as a theoretical template. It gives the event rate and event spectrum through inverse beta decay interactions with explicit model parameter dependence. Parameter estimation is performed on these simulated sample data by fitting least squares using the analytical solution. The results show that the mass, radius, and total energy of a remnant neutron star produced by an SN can be determined with an accuracy of ∼ 0.1 M⊙, ∼1 km, and ∼ 10⁵¹ erg, respectively, for a Galactic SN at 8 kpc

Large edge magnetism in oxidized few-layer black phosphorus nanomeshes

The formation and control of a room-temperature magnetic order in two-dimensional (2D) materials is a challenging quest for the advent of innovative magnetic- and spintronic-based technologies. To date, edge magnetism in 2D materials has been experimentally observed in hydrogen (H)-terminated graphene nanoribbons (GNRs) and graphene nanomeshes (GNMs), but the measured magnetization remains far too small to allow envisioning practical applications. Herein, we report experimental evidences of large room-temperature edge ferromagnetism (FM) obtained from oxygen (O)-terminated zigzag pore edges of few-layer black phosphorus (P) nanomeshes (BPNMs). The magnetization values per unit area are ~100 times larger than those reported for H-terminated GNMs, while the magnetism is absent for H-terminated BPNMs. The magnetization measurements and the first-principles simulations suggest that the origin of such a magnetic order could stem from ferromagnetic spin coupling between edge P with O atoms, resulting in a strong spin localization at the edge valence band, and from uniform oxidation of full pore edges over a large area and interlayer spin interaction. Our findings pave the way for realizing high-efficiency 2D flexible magnetic and spintronic devices without the use of rare magnetic elements

FEM Analysis for Sinusoidal Perturbation of Hydrogen Permeation into a Steel Sheet

Numerical calculation for the diffusion problem of hydrogen absorbed in a steel sheet during hydrogen permeation measurement using a double electrochemical cell was carried out. The finite element method (FEM) was applied to obtain the concentration distribution of hydrogen expressed by one- or two-dimensional Fick’s laws in the sheet, assuming that hydrogen concentration at the hydrogen entry interface was perturbed sinusoidally and both the hydrogen entry and exit reactions were in a mass-transport controlled process. From a comparison with experimental results reported previously, in which a phase shift from entry current to exit current waves observed on a single grain of the specimen sheet was at least two-times larger than that on two grains, it was estimated that the diffusion coefficient at a grain boundary located between two grains was five orders in magnitude larger than that on a single grain

Large edge magnetism in oxidized few-layer black phosphorus nanomeshes

et al.The formation and control of a room-temperature magnetic order in two-dimensional (2D) materials is a challenging quest for the advent of innovative magnetic- and spintronic-based technologies. To date, edge magnetism in 2D materials has been experimentally observed in hydrogen (H)-terminated graphene nanoribbons (GNRs) and graphene nanomeshes (GNMs), but the measured magnetization remains far too small to allow envisioning practical applications. Herein, we report experimental evidences of large room-temperature edge ferromagnetism (FM) obtained from oxygen (O)-terminated zigzag pore edges of few-layer black phosphorus (P) nanomeshes (BPNMs). The magnetization values per unit area are ~100 times larger than those reported for H-terminated GNMs, while the magnetism is absent for H-terminated BPNMs. The magnetization measurements and the first-principles simulations suggest that the origin of such a magnetic order could stem from ferromagnetic spin coupling between edge P with O atoms, resulting in a strong spin localization at the edge valence band, and from uniform oxidation of full pore edges over a large area and interlayer spin interaction. Our findings pave the way for realizing high-efficiency 2D flexible magnetic and spintronic devices without the use of rare magnetic elements.This work at Aoyama Gakuin was partly supported by a Grant-in-aid for Scientific Research (Basic research A: 24241046 and Challenging Exploratory Research: 15K13277) and grant for private University in MEXT and AOARD grant (No. 135049) in U.S. Air Force Office of Scientific Research. The work in the University of Tokyo was also supported by Grant-in-Aid for Scientific Research on Innovative Area, “Nano Spin Conversion Science” (No. 26103003), and by Grants (Nos. 25247051 and 15K17676). S. R. acknowledges Funding from the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (No. FIS2015-67767-P (MINECO/FEDER)), the Secretaria de Universidades e Investigación del Departamento de Economía y Conocimiento de la Generalidad de Cataluña, and the Severo Ochoa Program (MINECO, No. SEV-2013-0295).Peer Reviewe

FEM Analysis for Sinusoidal Perturbation of Hydrogen Permeation into a Steel Sheet

Numerical calculation for the diffusion problem of hydrogen absorbed in a steel sheet during hydrogen permeation measurement using a double electrochemical cell was carried out. The finite element method (FEM) was applied to obtain the concentration distribution of hydrogen expressed by one- or two-dimensional Fick’s laws in the sheet, assuming that hydrogen concentration at the hydrogen entry interface was perturbed sinusoidally and both the hydrogen entry and exit reactions were in a mass-transport controlled process. From a comparison with experimental results reported previously, in which a phase shift from entry current to exit current waves observed on a single grain of the specimen sheet was at least two-times larger than that on two grains, it was estimated that the diffusion coefficient at a grain boundary located between two grains was five orders in magnitude larger than that on a single grain