In Japanese assessment of thermal environment, we generally express thermal sensation by using the words samui, suzushii, atatakai and atsui. In this paper, we relate internet search frequency of the thermal sensation words to outside temperature. We then propose a practical method for predicting future outside temperatures using Google Trends data.

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This paper reports the association between work life balance factors (work hours, commute time, teleworking), health behaviors (sleep duration and exercise habits) and mental health. A cross-sectional dataset (n=1997) obtained from a web-based survey of office workers in Japan was used for the analysis. Logistic regression analysis was used to adjust for confounding factors (gender, age, annual household income, marriage, occupation, employment type and position), and odds ratios (AOR) with 95% confidence intervals (CI) were calculated with no overtime work, less than 60 minutes/day commuting, and no teleworking as the reference group. As a result, overtime work and commuting more than 120 minutes/day were associated with sleep deprivation, teleworking was associated with daily exercise habits, and overtime work of more than 40 hours/month and commuting more than 120 minutes/day were associated with an increased risk of mental disorders.

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The authors examined the effects of wearing a collarless full harness (FH) compatible ventilated working vest (VWV), which was modified to facilitate the wearing of the harness (hereafter referred to as "new model"), on physiological and psychological responses of workers at a construction site during the summer. A VWV with a collar before improvement (hereinafter referred to as "conventional model") was used for comparison. A comparison of the physiological and psychological responses of seven subjects who wore the FH inside the VWV for the new model and outside the VWV for the conventional model showed no significant differences.

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This study measured the skin temperatures of workers at construction sites to verify the effectiveness of heatstroke prevention measures. The results suggest that a break and drinking water at 2 PM, which is implemented as a heatstroke countermeasure, may reduce the subsequent rise in workers' skin temperature.

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Kotatsu is one of the traditional heating methods in Japan, and especially Hori-Gotatsu (trench kotatsu) is sometimes used all year round as a part of living space because it is integrated with a dwelling unit. There have been few studies on the thermal environment of Hori-Gotatsu, and especially there are no studies on Hori-Gotatsu. The purpose of this study is to evaluate the thermal comfort of Hori-Gotatsu. In this paper, the thermal environment of Hori-Gotatsu is investigated by assuming the thermal environment of Hori-Gotatsu by CFD analysis and inputting the skin temperature calculated from the JOS-2 model to the Zhang model. In this study, it was found that there was almost no difference depending on the turbulence model used, but there was a significant difference in skin temperature by site depending on the size of the mesh used, which resulted in a spillover effect to thermal sensation and comfort.

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A method of improving the thermal environment by floor plan changes focusing on non-air-conditioned rooms with undressing activities was proposed to reduce the risk of heat shock. In this study, the influence of floor plan changes on the indoor thermal environment from the perspective of summer health in a detached house in temperate climate was verified by numerical simulation. As a result, the floor plan changes models focusing on non-air-conditioned rooms showed a small difference from the original model in terms of room temperature in the living room on the hottest day. However, in the room temperature of the toilet on the hottest day, it was up to 4K lower than the original model. Furthermore, some models showed a reduction in WBGT in non-air-conditioned rooms, suggesting that floor plan changes may improve the risk of heat stroke in non-air-conditioned rooms.

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This study aimed to clarify the effect of streaming water surface on the indoor thermal environment, measurements of the indoor thermal environment in summer and winter were conducted on a Kawabata in Yokokawa settlement, Shichikashuku town, Miyagi prefecture. As a result, a representative point in the Kawabata room during the day was affected by the outside temperature and solar radiation, the indoor thermal environment was hotter than the outside temperature in both summer and winter. On the other hand, a relatively cool environment in summer and a warm environment in winter were formed near the floor and streaming water surface in the Kawabata room. It was pointed out that due to the influence of the streaming water surface, which is relatively cool in summer and warm in winter, it may prevent the freezing of ripened pickles, especially in winter.

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In hot environments, exposure to sunlight lead to increased skin temperature, resulting in physical stress like higher heart rate, fatigue, and reduced sports performance. This impact is particularly notable in outdoor activities such as golf. A study investigated how clothing and sunscreen blocking near-infrared radiation (NIR) could affect the physical stress and performance. Ten healthy male golfers aged 18-22 were tested in hot conditions mimicking sunny summer weather. Tests are implemented under the following two conditions, control condition using regular clothing and UV-protective sunscreen, and a test condition using NIR radiation-blocking clothing and sunscreen. NIR blocking condition exhibited lower heart rate, reduced sweating compared to the control condition. The findings suggest that blocking NIR can alleviate physical strain and potentially enhance performance.

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Due to the deterioration of the hot environment in the summer season, Outdoor residents and pedestrians pay attention to behavioral adaptations. In this paper, we performed CFD analysis to analyze both the human physiological responses of parasol users and the microclimate around it. We also evaluated the effects of parasol use and transmittance on pedestrians' adaptation to hot environments based on CFD Analyses. Three cases were analyzed. In Case1, a pedestrian without a parasol stands alone in the computational domain, while in Case2, a pedestrian with the 30% transmittance parasol. Additionally, in Case3, the value of the transmittance of the parasol is changed from 30% to 15%, compared to case2. The analysis revealed that a decrease in the transmittance of the parasol reduces solar radiation, increases the surface temperature of the parasol, decreases skin temperature, and reduces sweating. Therefore, a decrease in the transmittance of the parasol improves the hot outdoor environment in summer. Future duel of this study is to clarify the optimal heat adaptation measures for pedestrians through the further investigations on analysis of the case of further increase in transmittance.

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No consistent conclusions have been reached regarding the effects of the thermal environment of office spaces on cognitive function. This study aims to achieve the following objectives: 1) to evaluate the effects of moderate heat exposure on cognitive function using EEG event-related potentials; 2) to identify physiological and psychological factors of changes in cognitive function through respiratory and circulatory measurements and questionnaires. Twenty young men and women were exposed to two environmental conditions for 3 hours: medium temperature (23°C) and high temperature (33°C) conditions, both with 60% relative humidity and air velocity less than 0.15 m/s. The results showed no significant differences in P300 amplitude of EEG event-related potentials or performance on the computational task between temperature conditions. However, physical fatigue was significantly stronger and cerebral blood flow tended to decrease over time under the high temperature condition. This suggests a negative effect on productivity, including cognitive function, during longer heat exposure.

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The purpose of this study is to evaluate effects of combinations between air conditioning and ceiling fans (CF) on both thermal environment and air quality in a residential atrium space. We examined these effects by changing CF operation, and evaluated the spatial distributions of airflow, thermal environment, and thermal comfort indexes in the summer and the winter seasons. From the results of the investigations, the following knowledges were found: (1) In both the summer and the winter seasons, the CF operation calmed the vertical differences of air temperature in the atrium space: (2) From the results of predicted mean vote (PMV), it was found that the CF operation improved the thermal comfort in the atrium space in the summer season, while not in the winter season. We suppose that the further investigations were needed because of concern that the results of the winter season were affected by the measurement locations of airflow.

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In this study, we conducted experiments on the effects of vertical temperature difference on physiological and psychological responses in women who are prone to skin temperature decrease. Experiments were conducted in a laboratory simulating an office under various temperature conditions, and physiological parameters such as skin temperature were measured, and psychological evaluation was conducted on 11 items including thermal sensation and thermal comfort. In addition, the experimental participants were asked to perform cognitive and memory tasks. The results confirmed that the combined use of the floor blowout affected the whole-body thermal sensation by preventing a decrease in lower body skin temperature. In addition, although there was no significant difference in scores for work efficiency, the results indicated that the sense of work efficiency was affected.

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A subject experiment was conducted in which the forearms of young female subjects were exposed to airflow at different wind temperatures to measure the threshold of wind speed at which they began to perceive airflow, and a subject experiment was conducted to measure the threshold of cold sensation in the same subject's forearms. As a result, the effect of the threshold of cold perception on the threshold of wind speed at which they began to perceive airflow was smaller than the results for the male subjects. Although extrapolated by the regression line, it was found that wind speeds of 0.4 m/s or higher are required to perceive airflow without cold sensation. At ambient temperature of 22℃, subjects were found to perceive airflow even at wind speeds of 0.1 m/s or less, and at ambient temperature of 30℃, no subjects perceived airflow even at wind speeds of 0.2 m/s.

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A “green curtain” using bitter gourd was installed outside the west window to improve the thermal environment and visual environment in the S University H campus EV hall. To understand the thermal and visual environment, air temperature, humidity, airflow, surface temperature, illuminance, and chromaticity were measured. In addition, a questionnaire survey was conducted to evaluate the impression of the space. As a result, the infrared thermography camera images allowed us to understand the effectiveness of the green curtains in blocking solar radiation, which was within the thermal comfortable range 74% of the time with the use of the green curtains. The illuminance on the desk top surface was at least 500 lx, so the environment was considered to be well-lit for a work environment.

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With the improvement of living standards, the number of people with obesity (high Body Mass Index, BMI) has been increasing. However, research on thermal environments during sleep for individuals with high BMI remains limited. This study aims to investigate the sleep environments of individuals with different BMI levels and to explore optimal thermal conditions for comfortable sleep.

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With the aim of preventing traffic accidents involving elderly drivers at night and during rainfall, visibility evaluation experiments were conducted on 144 image samples of four-color umbrellas with reflective tape affixed in three patterns (four locations, circumferential, radial) and four-color umbrellas without tape for two groups: young age and elderly-simulated groups. Visibility ratings for the young age group were significantly higher than the elderly-simulated group for all umbrellas (p<0.05). When the reflective tape was applied in the circumferential or radial direction, the visibility rating was 4.0 (slightly visible) or higher for both groups up to 50-60m points of low-beam illumination. The circumferential pattern was found to be more effective in improving visibility than the radial pattern because it uses less area of reflective tape and is more economical.

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As a measure to prevent medication errors, we focused on pictograms and conducted a survey targeting young women regarding their medication habits, awareness of medication pictograms, and opinions on comprehensible designs. Approximately 7% of the participants reported experiencing medication errors, with mistakes in timing and dosage frequency. The awareness of medication pictograms was about 20%, and the correct response rate for the content of five existing pictograms ranged from 64.1% to 98.1%. It was found that adding Japanese or English text was effective in making the pictograms easier to understand. Additionally, depictions of actual human actions, numbering instead of arrows to indicate sequences, and simplifying designs were suggested to be effective in making the pictograms more understandable.

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In order to understand the differences and characteristics of the hygiene management of medium-sized buildings and specified buildings from the subjective evaluations of building users, we conducted a secondary analysis of data from previous studies. Overall, complaints from employees were seen in 15-25% of properties regarding “temperature”, “humidity”, and “water leakage, condensation, and leaks”. Complaints about humidity were significantly higher in specified buildings, while complaints about “hygiene pests, etc.” were higher in non-specified buildings. With regard to the workplace environment that employees were aware of, “items related to humidity, temperature and ventilation” occupied the top positions, and in particular, “too dry” and “insufficient air flow, air stagnation” were perceived as regular problems by 10-20% of employees. In addition, employees in non-specified buildings were more aware of a wider range of issues than those in specified buildings, and the percentage of awareness was also higher. These results suggest that it is possible to understand to some extent the perception of employees regarding temperature, humidity and ventilation, and that this can be used as a trigger for appropriate environmental hygiene management.

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The objective of this study is to investigate the actual condition of workers’ clothes in an office in summer. The clo values were surveyed using a web-based questionnaire from August to September 2023 in six buildings (three of which were small- and medium-sized buildings) and was calculated based on the clo value database of ISO 9920. The results showed that the average value of basic thermal insulation of clothing （Icl） was 0.58 clo for males and 0.64 clo for females. Most of the male workers (73.5%) wore between 0.5 clo and 0.6 clo. Females were relatively more widely distributed than males, with 36.8% in the 0.5clo to less than 0.6clo category. The analysis by building size showed that the clo value was 0.56 clo for buildings larger than 3,000 m2 and 0.62 clo for small and medium-sized buildings, with significantly higher values for small and medium-sized buildings.

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In this study, as a basic investigation to propose a comfortable method of using air conditioners that considers the characteristics of cold constitution, we measured changes in skin temperature and subjective valuation of thermal sensation and thermal comfort under 25°C and 20°C conditions in the climate chamber with male and female university students as subjects and analyzed their physiological and psychological responses. Subjects with a cold constitution generally showed a marked decrease in peripheral skin temperature, and female subjects tended to show a greater decrease in skin temperature on the thighs and legs.

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In order to consider in gender differences in comfortable wind exposure in consideration of energy saving, we measured the physiological and the psychological response in the climate chamber. The subjects were 23 healthy young men and women. The subject adjusted the installation position of the spot electric fan and the speed of the air velocity so that the subject themselves was comfortable. The young men used the spot electric fan near their body and the air velocity was faster than young women. Similarly, the same trend was shown among the cold constitution.

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We conducted a web survey to find out about the problems people have when there is a long-term power outage due to a disaster (e.g. household electrical appliances that they want to be restored as soon as possible), the level of inconvenience they experience when there is a long-term power outage, and the possession and consideration of power supply equipment, as well as the reasons for this, with a focus on seasonal and regional differences. As a result, we found that there were seasonal and regional differences in the problems people have with ‘air conditioning equipment’. In addition, the proportion of people who owned power supply equipment was high among those who answered that they would not be troubled by a long-term power outage. In addition, the hurdle to purchase in terms of price was high for those who did not own power supply equipment, and the proportion of those who did not feel the need to purchase was high, especially among those who were not considering purchasing.

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It is believed that the temperature and humidity of the environment being evaluated affect odor evaluation. In last year's study, the effect of humidity in the odor bag on the threshold measurement was examined using the standard odor A (β-phenylethyl alcohol). In this study, we will continue to investigate the effect of humidity inside the odor bag on threshold measurements. The humidity inside the odor bag was set to two conditions: low humidity (30%～35%) and high humidity (90%～98%), and the odorants were the five standard odors used in the panel selection test. Liquid reagents were vaporized in a thermostatic chamber, sealed in odor bags, and presented to the subjects. Threshold values were calculated using the official three-point comparison triangle odor bag method. Six male and six female subjects in their 20s who passed the panel selection test were recruited. The results showed that the humidity inside the odor bag influenced the results of the threshold measurement depending on the characteristics of the odorant.

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One of the factors that affect daily sleep is social time constraints. We conducted a survey of daily sleep during two periods of different social time constraints (“busyness”) using actigraphy devices on college students who were living with many social time constraints, such as part-time jobs and test periods. The sleep of 33 female college students was analyzed for two weeks each during a “busy” and a “not busy” period. During the “busy” period, the time of leaving bed was significantly earlier than during the “not busy” period, and sleep duration was slightly shorter. When the relationship between sleep and the personal characteristics quantified by the questionnaire was examined, it was found that during busy periods, those with higher levels of neuroticism in their personality traits tended to spend more time to fall asleep.. The results suggest that individual characteristics may affect sleep under different social time constraints.

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In this study, we examined whether vascular endothelial function is involved as a mechanism of cold constitution. Flow mediated vasodilation (FMD) after releasing the brachial artery occlusion was evaluated using near-infrared spectroscopy and laser doppler flowmetry in 24 healthy young (21.8±2.2 years old) male students (each 12 in group with and without cold constitution). The results showed no significant differences between the groups in the 10-sec slope, maximum value, and time to reach the maximum of tissue oxygen saturation during FMD. However, the maximum value in forearm skin blood flow in the cold constitution group was significantly lower than that in the non-constitution group (P<0.05).

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The influence of cooling upper surfaces of seat on human thermal/comfort sensation and skin/core temperatures was examined through a subject experiment in outdoor stand in an aquarium in hot climate, during a consecutive process of standing, seating, and again standing for 20 minutes each. The surface temperature of the cooled seat was 28°C. Based on the subjects' declaration, the whole-body-sensation of “hot” was mitigated by cooling the seat surface, and there was a significant difference between the groups with and without cooling the seat surface. Both those who shifted toward comfort with seat surface cooling, and at the same time, those who did not were identified. Buttock skin temperature decreased when the seat surface was cooled, but increased for the case of no cooling. The buttock skin temperature was lower than that before seating, 20 minutes after leaving the cooled seat, while the thermal/comfort sensation, and forearm skin temperature returned to the same level as before seating.

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In order to evaluate the influence of partial cooling of the human body in a hot environment, we analyzed the results of a subject experiment in which the subject was exposed to a hot environment, sat in a cooling chair for 20 minutes, and then returned to the hot environment again, using a human body thermal model. By combining with the heat transfer model inside the chair, the tendencies of the measured buttock skin temperature and forearm skin temperature for both the cases of cooled and uncooled chairs were reproduced. The analytical model was used to predict the magnitude and the duration of influence of cooling the buttock by mean skin and core temperatures, and the blood flow and perspiration rates.

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A survey of the sleep environment in college students' home bedrooms throughout the year was conducted to investigate the relationship between sleep variables and thermal environment. The combined clothing insulation (clo) of bedding and clothing were measured with a woman thermal manikin in the climate chamber to estimate the thermal insulation of the clothing and bedding used by individuals in their homes. SET*was calculated and the relationships between the SET* and sleep variables were examined

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The average heart rate during sleep (SHR) is considered useful for evaluating autonomic nervous system activity during sleep. This study constructed a nonlinear model using all the obtained environmental factors as features to assess which environmental factors in the bedrooms of male subjects influence SHR, using Shapley values and Partial Dependence Plots. Nine male subjects were monitored over an extended period, measuring heart rate, body movements, room temperature, radiant temperature, relative humidity, bed temperature, carbon dioxide concentration, and illuminance. The results showed that SHR increased monotonically with body movement. Among environmental factors, room temperature and radiant temperature around 25-26[°C] were associated with the lowest SHR, while bed temperature above 32[°C] led to a steady increase in SHR. Sleep durations of less than seven hours showed a tendency for higher SHR, but there was little variation above seven hours. Absolute humidity showed a minimum SHR around 13[g/kg], and illuminance over 130[lx] showed a tendency for negative Shapley values. However it is necessary to carefully consider whether the results obtained from the model construction method used in this study are appropriate in terms of physiological mechanisms.

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This study investigated the effects of bathing method and time to bedtime on sleep in winter, and examined the relationship between indoor thermal environment and sleep. A total of 21 subjects, 10 male students and 11 female students in their 20s, participated in the study. The experiment was conducted in the subjects' homes under four conditions: 39°C and 42°C for bathing, 30 minutes and 90 minutes from bathing to bedtime, and the bedroom environment during sleep. For the bedroom environment, we combined a condition in which the air conditioner heater was turned on during sleep, a condition in which the air conditioner was set to run on a timer for 1 hour, and a condition in which the heater was not used. The results showed a gender difference, with men sleeping better at higher bath temperatures, which was associated with better sleep. The latency to fall asleep was shorter for women under the condition of air conditioner heating, suggesting that the effect of heating was greater than that of bath temperature.

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The physiological and psychological responses of the human body at the start of air conditioning were explored in a total of four experimental rooms, that is, standard and low-emissivity (low-e) interiors, individually combined with two types of window glass, low-e and regular windows. The results showed that both temperature and PMV decreased faster in the low-e room than the standard room, and such lower values were maintained until the end of the experiment. The difference in window glass specifications more remarkably clarified, the difference in these measured values between the standard and low-e rooms. Among the physiological responses, the skin temperature decreased after subjects enter the room, and the degree of the decrease was greater in the low-e room than the standard room. The temperature of the room with the low-e window glass was about 0.5°C lower than that in the room with regular window glass. Psychologically, the subjects only in the low-e environment felt “cool” over time, and the combination of the low-e window made them more rapidly felt “cool” than the combination of the regular window. To conclude, physiological and psychological responses are strongly influenced by the low-e environmental condition in the viewpoints of transitional and settled periods.

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The objective of this study is to evaluate the increase in heat and the effectiveness of summer resorts in cities and resort areas in the summers of 2014 and 2023. WBGT data from the Ministry of the Environment was used to calculate the number of hours exceeded and the accumulated temperature. Except for resort areas in highland plateaus, a significant trend toward increased heat was observed in 2023 in both cities and resort areas. Furthermore, the change in heat load could be evaluated by the relative value ratio of the number of hours and the accumulated temperature. In seaside resorts, the effect of avoiding heat was seen in 2014, but in 2023 the environment was closer to that of an urban area.

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The purpose of this study was to clarify the thermal environment formed under two types of tarp tents. Thermal environment measurements were carried out in summer for tarp tents A and B, as well as without a tarp tent (in the sun). The following findings were obtained through the measurements. The MRT around noon was extremely high in the sun, reaching approximately 75 °C. Meanwhile, the MRT under the tarp tents were approximately 15 °C lower than in the sun at 1.1 m above the ground. The UTCI reduction of the tarp tents A and B at a solar radiation of 800 W/m2 were 2.1 °C and 2.3 °C, respectively.

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Physiological changes acquired in daily life in accordance with seasonal climate variations are referred to as seasonal acclimatization. This study examined the relationship between ambient temperature and physiological changes during daily life. From May to September 2024, subjects were conducted continuous exercise load experiments in a controlled climate chamber under a constant heat environment (32°C, 50% RH), measuring physiological responses to heat stress. Additionally, subjects carried temperature loggers to measure ambient temperatures during their daily activities. The ambient temperatures experienced by the subjects showed smaller variations compared to outdoor temperatures, with some days when the observed outdoor temperatures exceeded the subjects’ ambient temperatures by more than 6°C. Therefore, it was suggested that measuring ambient temperature is useful for assessing individual heat exposure. The results of the subject experiments indicated a negative correlation between ambient temperature and the increase in mean skin temperature and sweating rate, confirming the suppression of skin temperature rise and water loss as the hot season approached. It was also shown that subjects who regularly exercise exhibited a smaller increase in core body temperature, indicating superior heat tolerance.

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In this study, we conducted an experiment on the effects of wearing a vest with a fan in the office room after using cooling space. Among the three conditions compared, the condition with a cooling space of 24℃, a room of 28℃ after using cooling space, and wearing a cooling vest was the most comfortable and satisfying in office space. Heart rate did not differ between the three conditions, but sweating rate of abdomen was relatively high under the condition with a cooling space of 24℃ and a room of 28℃ wearing a cooling vest.

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A new index 'Heat Sensation Index (HSI)' is proposed to more accurately reflect the human thermal sensitivity to glass. This index is calculated by taking into account both the spectral transmission and emission characteristics of the glass as well as the spectral transmission and absorption characteristics of the human skin, in relation to the solar radiation reaching the outer surface of the glass. To validate the HSI, we conducted an experiment on a real vehicle with various types of glass in a climate laboratory. The results showed that the HSI correlates more closely with the thermal sensation of the participants than the total solar transmittance Tts, which is the conventional index to assess thermal performance of glass.

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To evaluate the effectiveness of using a vest with fans for working in an air-conditioned room using CFD analysis, this paper conducted an analysis that introduced a model construction and a human body thermal model. The shape of the human body and the shape of the work clothes with fans were created using a 3D scanner, and an analysis was performed by setting the measured fan air volume to evaluate the thermal sensation and comfort. To verify the analysis model, PIV measurements were performed and the wind speeds at the chin, nose, back of the neck, and back of the head were compared with the analysis results. As a result, when the work clothes with fans model was worn, the skin temperature decreased at the head, neck, chest, and back, and the thermal sensation and comfort of the whole body also decreased. The wind speed at the chin and nose was weaker in the CFD analysis than in the PIV measurement.

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Airflow velocity out of the opening and clothing thermal resistance were measured by changing the position of the inner pad inside the work clothes with fans. There were three conditions: one with the inner pad attached to the chest or back, and one without the inner pad positioned. Measurements were taken in an indoor environmental test chamber with a thermal mannequin wearing work clothes with fans and a full body harness safety belt under each condition. When the inner pad was placed on the back, the air velocity exiting the opening was greater than that of the back of the chest. The whole-body clothing thermal resistance was lowest in the condition with the back of the chest and was 0.03 clo lower than in the condition without the inner pad.

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In this study, in order to evaluate the degree of comfort of students learning in the classroom, we conducted observations of the thermal environment in the classroom twice a month from April to June and conducted a questionnaire survey for students. Students’ comfort level during class was compared between objective evaluation using PMV obtained in the classroom and subjective evaluation using thermal sensation and imagined temperature collected through a questionnaire. As a result, (1) thermal sensation and clo value, which are subjective evaluations, showed similar trends, but different trends from PMV. (2) Imagined temperature showed psychological adaptation of comfort level. (3) The negative correlation between imagined temperature and clo value suggested that it was also related to behavioral adaptation.

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This study focused on the environment near the skin, examining the temperature and humidity within clothing and their relationship with skin conditions. The investigation into the temperature and humidity within clothing revealed that the humidity on the back is higher than that on the arms and shins, with significant individual differences. The analysis of the relationship between temperature and humidity within clothing and skin conditions indicated that higher humidity inside clothing on the back correlates with a decrease in the barrier function of the stratum corneum and an increase in the degree of itchiness. It was suggested that even the level of humidity within clothing can deteriorate the barrier function of the stratum corneum, leading to a skin condition that is more susceptible to irritation.

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In order to clarify the skin characteristics that affect the occurrence of dryness sensation in winter, 56 subjects participated to measurements of skin characteristics (moisture content, oil content, elasticity, temperature, fineness of texture) and questionnaires on skin dryness sensation and lifestyle habits. The skin characteristics with significant differences between subjects who reported "do not feel dry much" or "feel dry very much" about daily skin dryness sensation were moisture content and texture. When they reported dryness more strongly, the skin moisture content and the skin texture were tended to lower and coarser, respectively. There were no significant differences in physical build or lifestyle habits (weight, frequency of exercise, frequency of drinking, sleeping time, bathing time) due to daily skin dryness sensation; all the subjects who had atopic dermatitis or smoking habit, a very small proportion of all, answered "feel dry somewhat" or "feel dry very much" about daily skin dryness sensation.

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Essential oils extracted from petals, leaves, roots, and other parts of plants possess a variety of scents. By effectively utilizing these essential oils, it is expected to enrich our living environments with pleasant scents and beneficial effects. This study aimed to clarify the relationship between impressions of scents and their aromatic components, focusing on 137 types of essential oils with various scent qualities. Odor samples were prepared by adding essential oils to screw-top vials to achieve an odor intensity of approximately level 3. These samples were presented to 36 university students for evaluation. The evaluation indicators included basic measures such as odor intensity, as well as indicators related to the impressions and emotions. In a study examining the relationship between the components of the 137 types of essential oils and impression ratings, it was found that essential oils containing high amounts of limonene, linalool and geraniol tended to receive relatively positive impression ratings.

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A high-precision living environment sensing device for academic research has been developed. It can measure dry-bulb temperature, relative humidity, globe temperature, and atmospheric pressure for comprehensive thermal environment evaluation. Designed for widespread use, this device features a safety-conscious form and battery, and enables humidity ratio, WBGT, and PMV calculations, as well as long-term data storage and measurement historical management in the cloud. In the future, we plan to add additional sensors and enhance features such as psychrometric charts.

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The purpose of this study was to investigate the effects of humidity conditions in an isothermal SET* environment on mental stress, arousal, fatigue, and task performance. The experiment was conducted in two isothermal SET* environments (approximately 26°C and 28°C) under four conditions combining temperature and humidity. In this experiment, the relative humidity of the high-humidity condition was set at 70% and that of the low-humidity condition at 30%. The findings are as follows. In the SET*26 ℃ environment, there were no significant differences in thermal comfort, mental stress, arousal, fatigue, or task performance due to the humidity conditions. This suggests that controlling the room temperature to 28 ℃ and relative humidity to 30 % or 26.5 ℃ and relative humidity to 70 % in the summer does not affect comfort, stress, or task performance.

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