Search

Tsunamis, such as the 2004 Indian and 2011 Japan tsunamis, routinely cause severe damage along coasts. Coastal vegetation serves as an excellent, naturally occurring protection from tsunamis. However, prior studies focusing on the wave attenuation by vegetation assumed that solitary waves would adequately represent the major aspects of tsunamis. However, there are substantial differences between solitary tsunami waves with regards to their wave profiles and how it evolves with time. This study aims to improve our understanding of the wave-vegetation interactions by employing a more realistic wave profile (tsunami-like instead of solitary). This work uses measurements obtained during the 2011 Japan tsunami to parameterize the observed tsunami-like wave profile, which is then used to investigate the wave-vegetation interaction on a sloped beach, using a nonhydrostatic wave (NHWAVE) model. The work investigates the efficiency of vegetated sloped beach in mitigating the maximum run-up height and total wave energy as function of wave height, water depth, vegetation width, vegetation density and wave model (solitary vs. tsunami-like). Results show that a vegetated sloped beach is effective in reducing the wave energy of both kinds of waves. However, when a solitary wave is used, the vegetation patch is shown to be relatively better at attenuating wave energy and in reducing maximum run-up heights. The findings indicate that the solitary wave model overestimates protections afforded by coastal vegetation, and that it underestimates maximum run-up heights. The findings drawn from this study further broaden our understanding on the wave attenuation of tsunami surges and waves by a vegetated sloped beach. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the metro stray current cannot be directly numerically measured by the existing methods, and the data acquisition distortion caused by the special operating environment of the metro system, a new on‐line monitoring method for stray current was put forward in this paper. First, the stray current distribution function at different positions of metro trains was derived. Then, the equivalent circuit of stray current was built according to the field measured environment, and the numerical calculation formula of stray current was deduced. On the basis of the formula, the metro stray current could be calculated by the real‐time monitoring data, and the calculated data can be filtered and fitted with the stray current distribution function. In order to identify the distorted data, the potential energy function was introduced to judge the deviation degree of data point from the fitting function, so the erroneous data can be effectively eliminated. Thus, the accurate distribution value of stray current along the metro track was obtained. Taking a metro station in a certain city as the prototype, the CDEGS simulation model was built to verify the proposed method. The simulation results showed that even under the condition of sampling data distortion, the method could directly calculate the stray current value in real time, which had strong fault tolerance. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

As for research on sector-coupled energy systems, few studies comprehensively deal with energy carriers and energy demand sectors. Moreover, few studies have analyzed energy conversion functions such as Power-to-Gas, Power-to-Heat, and Vehicle-to-Grid on the energy system performance. This study clarifies the required renewable resources and costs in the sector-coupled energy system and cost-optimal installed capacity and operation. We formulated an optimization model considering sector coupling and conducted a case study applying the model in the Tohoku region. As a result, due to sector coupling, the total primary energy supply (TPES) is expected to decrease, and system costs are expected to increase from 1.8 to 2.4 times the current level. System costs were minimized when maximizing the use of V2G by electric vehicles and district heating systems (DHS). From the hourly analysis, it becomes clear that the peak cut effect by Power-to-Heat and the peak shift effect by Vehicle-to-Grid result in leveling the output of electrolyzer and fuel synthesizer, which improves the capacity factor reducing capacity addition. Since a large amount of renewable energy is required to realize the designed energy system, it is necessary to reduce the energy demand mainly in the industrial sector. Besides, in order to reduce costs, it is required to utilize electric vehicles by V2G and provide policy support for district heating systems in Japan. [ABSTRACT FROM AUTHOR]

This study investigated differences in the color association with energy drinks between two populations in different cultures, i.e., Taiwanese and Japanese. An anonymous, self-administered paper questionnaire was administered to first- and second-year students at National Taiwan Normal University (Taiwan) and Naragakuen University (Japan). In our inter-country, gender-stratified comparison, the color selected most often in response to the question, "What color comes to your mind for energy drink label?" was red for the Taiwanese and blue for the Japanese. The color associations with energy drinks selected by 20% or more participants in at least one population and showing statistical difference were extracted as noticeable difference. The present study demonstrates that the color and energy drink functions are closely associated. Specifically, yellow and nourishment, black and stimulant, yellow and vitamin supplement, green and dietary fiber supplement, and red and iron supplement are tightly associated regardless of the country. The strong tie between cosmetic and white is specific to the Taiwanese consumers. This suggests that careful color selection based on consumers' environmental and cultural backgrounds is important in communicating information regarding energy drink functions. It would be worth for energy drink manufacturers to consider those associations in designing labels for products. [ABSTRACT FROM AUTHOR]