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Human activities, including walking, generate an airflow, commonly known as the slipstream, which can disperse contaminants indoors and transmit infection to other individuals. It is important to understand the characteristics of airflow to prevent the dissemination of contaminants such as viruses. A cylinder of diameter 500 mm, which is the average shoulder width of an adult male, was installed in a motorcar and moved at a velocity of 1.2 m/s, which is the walking speed of an adult male. The velocity profile of the slipstream generated during this movement was measured by locating the sensor support at 0.15–2.0 m behind the cylinder. The wind velocity was set to 1.2 m/s to conduct the numerical analysis. The measurement data revealed the velocity profile of the space behind the cylinder, and a comparison of the numerical analysis and the measurement results indicate very similar u (measured velocity)/U (moving velocity) results, with a maximum difference of 0.066, confirming that the measured values were correctly estimated from the results of the numerical analysis.

In this study, measurements were carried out to identify the generation characteristics of wear particles emitted under a subway cabin during operation. Along with a fast mobility particle sizer, probes were installed under a subway cabin and in a subway tunnel to measure the size distributions of nanoparticles at 1-s intervals. Based on the particle density measured under the cabin minus that measured in the tunnel, the size distribution of wear particles generated under the cabin during deceleration was estimated to be bimodal at 165.5 nm and 6.98 nm. These particles were most likely generated from wheel-rail contact, as the train utilized electric braking (no mechanical force applied). In addition, a change in the wear mechanism appears to have arisen due to the increased temperature of the wheel-rail contact while nanoparticles were being emitted, leading to an initial generation of 165.5-nm particles followed by 6.98-nm particles 1 s later.

In this study, we describe a novel peroxidase-like activity of Co-aminoclay [CoAC] present at pH ~5.0 and its application to fluorescent biosensor for the determination of H2O2 and glucose. It is synthesized with aminoclays (ACs) entrapping cationic metals such as Fe, Cu, Al, Co., Ce, Ni, Mn, and Zn to find enzyme mimicking ACs by sol–gel ambient conditions. Through the screening of catalytic activities by the typical colorimetric reaction employing 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid)diammonium salt (ABTS) as a substrate with or without H2O2, Fe, Cu, and CoACs are found to exhibit peroxidase-like activity, as well as oxidase-like activity was observed from Ce and MnACs. Among them, CoAC shows exceptionally high peroxidase-like activity, presumably due to its ability to induce electron transfer between substrates and H2O2. CoAC is then used to catalyze the oxidation of Amplex® UltraRed (AUR) into a fluorescent end product, which enables a sensitive fluorescent detection of H2O2. Moreover, a highly sensitive and selective glucose biosensing strategy is developed, based on enzyme cascade reaction between glucose oxidase (GOx) and CoAC. Using this strategy, a highly linear fluorescence enhancement is verified when the concentration of glucose is increased in a wide range from 10 μM to 1 mM with a lower detection limit of 5 μM. The practical diagnostic capability of the assay system is also verified by its use to detect glucose in human blood serum. Based on these results, it is anticipated that CoAC can serve as potent peroxidase mimetics for the detection of clinically important target molecules.

The part-feeding system at an assembly shop controls the feeding of parts from the warehouse to workstations of the assembly shop in accordance with the production of vehicles. The part-feeding system plays a crucial role in determining the level of the inventory and stockout rate at the automotive assembly line. In this study, we propose a dynamic part-feeding system for an automotive assembly plant which estimates the part consumption amounts dynamically considering the actual production progress and directs the feeding orders dynamically to feeders. The results of a simulation show that the proposed dynamic feeding system produces better results than a static feeding system.

This paper analyzes how the vegetable production region in Yachiyo Town has developed, clarifies the basis on which it is sustained and discusses the sustainability of rental fallow land use. The settlement of Osaki, which specializes in vegetable production, is selected as the study area in Yachiyo Town.Until about 1960, the main form of agriculture in Yachiyo Town was wheat and barley. A method of cultivation for water melons and Chinese cabbages was introduced by a regional leader in the early 1950s. The introduction of this method of cultivation is related to changes in the economic environment-for example, the importation of wheat after World War 2. The vegetable production region in Yachiyo Town is categorized in two stages based on the type of selling: The first stage in which the requirements of farm groups is sought, and the second stage in which the marketing of the individual farm is sought. The market, which is organized privately in the surrounding area, was established in the early 1960s. Most of the Chinese cabbages are shipped to the Tohoku and Hokkaido regions through these markets. As a result, Yachiyo Town is devoted to growing Chinese cabbage and occupied the first rank in Japan in the late 1960s.However, its productivity declined due to the repeated mono-cultivation of melons and Chinese cabbages. Vegetable production in vinyl plastic hothouses was introduced in the early 1970s, but this was not developed into the dominant agricultural form. The farmhouse has managed a large amount of rental fallow farmland both within and outside the area of the town. Internal factors, including social relationships between landlord and tenant farmer have influenced the farmer's decision-making with implications for the development and sustainability of the vegetable production region.