Correlations between subjective sleep latency evaluated at the time of waking and objective sleep latency by polysomnography, sleep stage appearance ratio, and subjective sleep feelings at the time of waking were investigated in healthy young male adults. The authors re-analyzed the data recorded in the experiment that evaluated the light environment before sleep, and examined the data for 150 nights measured from 8 to 10 nights per participant and the mean values calculated for each of the 16 participants. Looking at the daily fluctuations in subjective sleep latency, the first-night effect was not clear, and the time interval of self-evaluation tended to change according to the length of subjective sleep latency. Correlation analysis of data from 16 participants showed that subjective sleep latency had a significant moderately correlation with each objective sleep latency obtained from PSG, and showed the strongest correlation with Stage 2 latency. Furthermore, there was a significant positive correlation with the occurrence rate of Wake in the first segment of sleep divided into four, and a significant moderately negative correlation with OSA factor IV (integrated sleep) in the subjective sleep feelings upon awakening. In addition, some of the participants with short objective sleep latency estimated longer subjective sleep latency, and it is thought to be related to lower subjective sleep feelings. From the above results, the sleep state at the beginning of sleep is subconsciously memorized to a certain extent, and the results recalled when waking up are reflected in the subjective sleep latency. Furthermore, it is suggested that the integrated sleep feeling is strongly involved to the subjective sleep latency. In conclusion, by measuring and recording one person over multiple nights, it is expected that we have obtained new knowledge that will contribute to sleep evaluation methods in daily life.

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Heavy rainfall caused by a baiu-front from July 5 to 8, 2018 and by an autumn rain front from August 11 to 14, 2021 raised the water level of the Chikugo River, resulting in internal flooding in Kurume City, located in the Chikugo region of southern Fukuoka Prefecture. In particular, in the watersheds of the Kanamaru and Ikemachi Rivers, which are tributaries of the Chikugo River, factories, houses, and apartment complexes were flooded and suffered flooding depths of up to 150 cm. The Kanamaru and Ikemachi river basins are flood plains, and in 1900, rice paddies were spread over low-lying areas. However, in the 1960s, a central purification center was constructed, and in the 1980s, an industrial park was opened and houses and apartment complexes were gradually built. The flooding damage in 2018 and 2021 was caused by the Kogasaka Drainage Pump Station on the Kanamaru River, which flows into the Chikugo River, closing the sluice gate due to the rising water level of the Chikugo River caused by heavy rains and the inability to operate drainage pumps due to the rising water level. Currently, efforts are being made by Fukuoka Prefecture and Kurume City to reduce internal flooding.

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The purpose of this study was to examine the influence of students' perceptions of time management on their use of time management. Perceptions of effectiveness, cost, and desirability of three aspects of time management (time assessment, planning, and monitoring) were measured, and the influence of each on time management use was examined. The analysis revealed that perceptions of time management influence time management use, with positive effects for effectiveness and desirability, and negative effects for cost. In particular, the perception of learning effectiveness was shown to have a positive influence on all three aspects of time management.

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This article did a case study with a model using the Grant-in-Aid for Scientific Research called KAKENHI and the number of publications, such indices are popular and basic in the evaluations of research capability of researchers. Through this investigation, the causal relationship involving only these two indicators diversifies the situations of researchers. In this situation, making an ideal and uniform guideline of career path, finding underperforming researchers according to this guideline, and providing supports might not work well because of the variety of the situations of researchers. Then this article conclude that the research support office of the university should prepare many choices of support programs based on the cost-benefit analysis, even when some of which may be rather unlikely to be used, in order to enable researchers to use the desirable support when they want them. Considering the capability of research takes on the character of the Time Study because it relates to the research activities located here and there on the axis of time. Considering causality also relates to the Time Study because it studies the reason and the result, and the reason is located the past side of the time axis comparing to its result. In addition to this, this article contributes to the society because it introduces a basic finding which can be used as a reference for research promotions.

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