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Microbubbles coated by visco-elastic shells are important for ultrasound diagnosis using contrast agents, and the dynamics of single coated bubbles has been investigated in the literature. However, although a high number of contrast agents are used in practical situations, there has long been an absence of a nonlinear acoustic theory for multiple coated bubbles, except for our recent work by Kikuchi and Kanagawa ["Weakly nonlinear theory on ultrasound propagation in liquids containing many microbubbles encapsulated by visco-elastic shell," Jpn. J. Appl. Phys. 60, SDDD14 (2021)], under several assumptions to be excluded. Aiming for generalization, in this study, we theoretically investigate weakly nonlinear propagation of ultrasound in liquid containing multiple bubbles coated by a visco-elastic shell with compressibility. Leveraging the method of multiple scales, both the Korteweg–de Vries–Burgers (KdVB) equation for a low-frequency long wave and nonlinear Schrödinger (NLS) equation for a high-frequency short wave are derived from the volumetric averaged equations for bubbly liquids based on a two-fluid model and the up-to-date model for single coated bubbles with shell compressibility. Neglected factors in our previous paper, i.e., compressibility of the shell and liquid, drag force acting on bubbles, bubble translation, and thermal conduction, are incorporated in the present KdVB and NLS equations; the proposed model will be regarded as a generic physico-mathematical model. The results show that shell compressibility attenuated ultrasound strongly and decreased nonlinearity of ultrasound. Finally, we compared the magnitudes of six dissipation factors (shell compressibility, shell viscosity, liquid compressibility, liquid viscosity, thermal effect, and drag force) for five typical ultrasound contrast agents, and a similar tendency between KdVB and NLS equations was revealed. [ABSTRACT FROM AUTHOR]

In the art museum, lighting plays a crucial role in visitors' understanding and appreciation of exhibits. This paper mainly explores the influence of different lighting mode (general lighting, accent lighting, and mixed lighting) and correlated color temperature (CCTs) (4000 K and 2700 K) changes on the observers' psychology to find the best lighting environment. Based on the simulation carried out at the National Museum of Western Art in Japan, we made six diverse lighting designs. 31 observers were invited to evaluate each scheme, and the results of subjective evaluation were analyzed by means of one-way analysis of variance and the paired sample T-test. According to the results of data analysis, suggestions can be given for art gallery lighting design. It is not recommended to use general lighting alone in art museums, and it is better to use mixed lighting. When the CCT is 4000 K, only accent lighting can be used. When the CCT is 2700 K, the mixed lighting effect is better. [ABSTRACT FROM AUTHOR]

This paper reports on the design and characteristics of a compact module integrating an optical displacement sensor and an electromagnetic actuator for use with vibration–isolation systems installed in KAGRA, the 3-km baseline gravitational-wave detector in Japan. In the technical concept, the module belongs to a family tree of similar modules used in other interferometric gravitational-wave detector projects. After the initial test run of KAGRA in 2016, the sensor part, which is a type of slot sensor, was modified by increasing the spacing of the slot from 5 mm to 15 mm to avoid the risk of mechanical interference with the sensor flag. We confirm that the sensor performance is comparable to that of the previous design despite the modification. We also confirm that the sensor noise is consistent with the theoretical noise budget. The noise level is 0.5 nm/Hz1/2 at 1 Hz and 0.1 nm/Hz1/2 at 10 Hz, and the linear range of the sensor is 0.7 mm or more. We measured the response of the actuator to be 1 N/A and also measured the resistances and inductances of coils of the actuators to confirm consistency with theory. Coupling coefficients among the different degrees of freedom were also measured and shown to be negligible, varying little between designs. A potential concern about thermal noise contribution due to eddy current loss is discussed. As of 2020, 42 of the modules are in operation at the site. [ABSTRACT FROM AUTHOR]

Typhoon-induced P-wave microseisms can be observed using seismological arrays and analyzed for the seismic monitoring of ocean storms. This paper presents a frequency-domain beamforming (FB) method that integrates a three-dimensional (3-D) Earth model to better capture the heterogeneities in the subsurface structure, and therefore yield more accurate ray-tracing and travel-time predictions. This method is applied to the Super Typhoon Lupit (2009) using seismological array observations from the Northeast China Extended Seismic Array (NECESSArray) and high-sensitivity seismograph network in Japan (Hi-net). The results show that the localized P-wave microseism source regions based on the 3-D model are in better agreement with the theoretical source regions and typhoon centers than those based on a conventional one-dimensional (1-D) model. The significance of using a 3-D model instead of a 1-D model in the FB method is further investigated by comparing the consistency of the localization results for the two different arrays, with the localized source regions being more mutually concordant when using the 3-D model. The results demonstrate that integrating the 3-D model into the FB method improves the accuracy of locating the typhoon-induced P-wave microseism source regions. [ABSTRACT FROM AUTHOR]

The energy-resolved neutron imaging system, RADEN, has been installed at the pulsed neutron source in the Materials and Life Science Experimental Facility of the Japan Proton Accelerator Research Complex. In addition to conventional neutron radiography and tomography, RADEN, the world's first imaging beam-line at a pulsed neutron source, provides three main options for new, quantitative neutron imaging techniques: Bragg-edge imaging to visualize the spatial distribution of crystallographic information, resonance absorption imaging for elemental composition and temperature information, and polarized neutron imaging for magnetic field information. This paper describes the results of characterization studies of the neutronic performance and installed devices at RADEN and shows the results of several demonstration studies for pulsed neutron imaging. [ABSTRACT FROM AUTHOR]

The rapid development of wind energy in Japan and the associated high uncertainties and fluctuations in power generation present a big challenge for both wind power generators and electric grids. Accurate and reliable wind power predictions are necessary to optimize the integration of wind power into existing electrical systems. In this study, a hybrid forecasting system of wind power generation was developed by integrating the Kalman filter (KF) with the high resolution Weather Research and Forecasting (WRF) model as well as an empirical formula of wind power output (power curve). The system has been validated with observations including wind speed and power output over a six-month period for 15 turbine sites at a wind farm in Awaji-island, Japan. The results show that the tuned WRF model is able to provide hub-height wind speed prediction for the target area with reliability to some extent. The predicted wind field can be substantially improved by the Kalman filter as a post-processing procedure. The 15-turbine averaged improvements of mean error, root mean square error, and correlation coefficient are 97%, 22%, and 10%, respectively. Meanwhile, the Kalman filter also demonstrates a promising capability of reducing the uncertainties in the power curve model. Systematic validations regarding both wind speed and power output were carried out against the observations for the target wind farm, which show that the hybrid power forecasting system presented in this paper can be an effective and practical tool for short-term predictions of wind speed and power output in Japan area. [ABSTRACT FROM AUTHOR]

A 1.2×1.2 m² muon tracker was moved from Los Alamos to the Toshiba facility at Kawasaki, Japan, where it was used to take ∼4 weeks of data radiographing the Toshiba Critical Assembly Reactor with cosmic ray muons. In this paper, we describe the analysis procedure, show results of this experiment, and compare the results to Monte Carlo predictions. The results validate the concept of using cosmic rays to image the damaged cores of the Fukushima Daiichi reactors. [ABSTRACT FROM AUTHOR]

In this paper we draw up future roadmaps for technologies, policies, and optimal investment timing toward the achievement of a low-carbon society (LCS) in Japan by 2050. Future pathways for Japan to follow are calculated using an analytical model based on a backcasting methodology. Early actions can lead to pathways for minimizing the costs toward a LCS in Japan. However, to take early actions, large investments will be needed at the initial stages. The investment requirements for the residential and commercial sector and transportation sector will be especially costly: The former reaching 2.5 trillion JPY annually from 2010 to 2025 and the latter reaching 2.5 trillion JPY annually from 2010 to 2015. There are four main advantages to early actions. (1) Technologies have learning-by-doing effects: The additional cost of reducing CO2 emissions will fall as the technologies spread. (2) If actions are delayed, learning-by-doing effects may fail to work sufficiently, resulting in higher total investment requirements for achieving a LCS. (3) No infrastructure can be built immediately; hence it would be difficult to switch suddenly to a LCS in the years just before 2050. (4) Future technological development has several uncertainties. If the development of one of the currently dominant technologies falls behind schedule, it will fail to spread as expected and CO2 emission targets will not be met. Early actions will open up new opportunities for the spread of alternative actions toward the LCS should a dominant technology fail in some way. [ABSTRACT FROM AUTHOR]

The aim of this paper is to define low carbon society (LCS) based on the phase diagram with the variables from the IPAT [Human Impact (I) on the environment equals the product of population (P) affluence (A) and technology (T)], starting from the problem definitions: (1) Economy is not everything for LCS and (2) it is not clear if speed on the constraint is more important than liberation from it. To tackle these problems, two research questions are set: (1) What are the basic indicators, objects, and constraints to shape the argument of LCSs and (2) what are the historical paths of several countries and what can be said for their future paths toward carbon societies? Time series data from 1900 or before are used, while the phase diagram with the variables from the IPAT equation is used as the core methodology. In addition to the IPAT variables, the importance of land per capita shall be considered as another basic indicator for LCS related to the carrying capacity. The three different kinds of objects [i.e., total gross domestic product (GDP), GDP per capita, and social indicator] and the two constraints (i.e., total emission and emission per capita) are considered, and it is shown that the combination of these objects and constraints strongly affects the argument of the carrying capacity of climate and land, development of economic system and economic man, and other human developments. Among the four cases analyzed in the phase diagram, the case where GDP per capita is object and total emission is constraint is given the most attention and requires the further research in the future since it does not contradict with a definition of LCS. It is also suggested that if changing the direction of the path with low carbon technology development takes time and cost, institutional arrangement would be additionally necessary in addition to market mechanism where optimal solutions are found on constraint. [ABSTRACT FROM AUTHOR]

In this paper, a sperm whale click analysis scheme is proposed in order to calculate the position of individual sperm whales in a group using data received at two arrays deployed near the surface. The proposed method mainly consists of two parts: short baseline (SBL) with classification and long baseline (LBL) with class matching. In SBL with classification, a click is automatically detected, and its direction of arrival is calculated. The clicks are then classified based on their direction vectors. The class data are then sent together with direction data and matched to the other array’s class data. LBL with class matching is used for localization. The classification algorithm can be used to estimate the number of whales clicking and to list potential candidates for LBL matching. As a result, the proposed method is able to localize the positions of the whales in a group. The performance of the proposed method is evaluated using data recorded off Ogasawara islands with two arrays near the surface. The three-dimensional underwater trajectories of six sperm whales are extracted to demonstrate the capability of the proposed method. [ABSTRACT FROM AUTHOR]

Annoyance to noise is probably a good measure of the potential for complaint and community action. Each individual’s degree of annoyance to noise cannot be accurately predicted from conventional laboratory studies and social surveys. Therefore, a logistic prediction model for individual allowable noise levels has been developed. In a previous paper [K. Furihata et al., Acta Acust. Acust. 93, 73–83 (2007)], an annoyance scale using the most frequently used annoyance ratings related to noise for community noise assessment in Japan was constructed. The dose-response relationships were obtained by actually listening to sounds in a field situation (1474 subjects) carried out at 14 metropolitan cities in Japan. The logistic prediction model was developed using the logistic regression parameters estimated from each cumulative percentage curve of seven annoyance scale scores based on all data (n=2940). To verify the hypothesis, individual relationships between annoyance and LAeq, (5 min) for 24 normal-hearing subjects were constructed using a laboratory experiment. The main conclusion drawn from the results is that if at least one dose-response relation is obtained from each subject, the model can predict whether a sound is annoying or not from its LAeq,(5 min) value. Moreover, validation of the model is needed in a field situation. [ABSTRACT FROM AUTHOR]

The Low Temperature Microgravity Physics Facility currently in the design phase is a multiple user and multiple flight facility intended to provide a long duration low temperature environment onboard the International Space Station. The Facility will provide a unique platform for scientific investigations requiring both low temperature and microgravity conditions. It will be attached to the Japanese Experiment Module's Exposed Facility and can house two science instruments each flight. The Facility consists of a 180-liter superfluid helium dewar, a support enclosure, and control electronics. The facility will be launched full of cryogen, and retrieved after the cryogen is depleted. Industrial partners are responsible for building the reusable facility and standard parts of the instruments. Principal Investigators from universities and other institutions are contracted to develop major parts of the science instrument package. An overview of the detailed technical capabilities of the facility will be presented in this paper. [ABSTRACT FROM AUTHOR]

The SPring-8 project is in progress in Japan. The main facility is an 8 GeV storage ring dedicated to synchrotron radiation [H. Kamitsubo et al. (this conference)]. The main feature of the ring is in the free straight sections 30 m long. In this paper the design of the long straight sections and how to use them is described. The long free straights are achieved through two phases to make the commissioning of the ring smooth. In the second phase, the long free straight sections are available. These long straight sections have the following potential to realize (1) extremely high brilliance, (2) multiundulators with broadband, and (3) free electron lasers. The emittance of the stored electron beam can be reduced to subnano m tad at 4 GeV with damping wigglers. Three-order higher brilliance can be obtained around 4 keV. With these optics, three-dimensional simulation was performed for free electron lasers (FEL). The calculated gain was not so large in the practical peak current level. [ABSTRACT FROM AUTHOR]

The experimental basis and instrumentation for the Gekko XII laser fusion program developed at the Institute of Laser Engineering (ILE), Osaka University are presented. Many diagnostics are in use to evaluate the key parameters of target implosion in an extremely dense, short period region. In this paper, we describe the present status and future planning of these diagnostics, such as xray, radioactive, and reaction particle measurement, because of their importance for fuel ρR determination. [ABSTRACT FROM AUTHOR]

Presents an abstract of a paper detailing the construction of the Australian National Beamline Facility at the Photon Factory in Tsukuba, Japan. Sources of funding for the facility; Aim to provide Australian scientists with routine access to synchrotron radiation in the hard-x-ray region; Description of the multiconfiguration diffractometer installed at the beamline.

Presents an abstract of a paper on the results of high-resolution triple-crystal x-ray-diffraction experiments performed at the Australian National Beamline Facility at the Photon Factory in Tsukuba, Japan. Capabilities of the BIGDIFF two-axis high-resolution vacuum diffractometer; Lattice distortion; Depth resolution that is achievable using BIGDIFF.