This study developed flooring and carpet materials with consideration for vibration damping and conducted experimental evaluations on their effectiveness in reducing heavy-weight floor impact sound and their perceived hardness during walking. For the 63 Hz frequency band of heavy-weight impact sound, reductions of 1–3 dB were observed on a concrete slab, and 4–7 dB on dry-type floating floors. In terms of walking comfort, subjective evaluations indicated that the materials were generally perceived as neutral or easy to walk on, demonstrating a balance between acoustic performance and usability.

This paper aims to improve the accuracy of an empirical method for predicting train-induced ground vibration in viaduct sections. We first investigated values of distance attenuation on surface ground in the cases with/without considering dynamic characteristics of a viaduct foundation using a numerical simulation. Secondly, a formula to estimate the correction value of the distance attenuation that is used by the empirical prediction method was proposed based on the simulation results. Finally, the applicability of the formula was investigated by comparing with field measurement records. The result showed that the prediction accuracy is improved by using the proposed formula.

In Japan, there are no standards that define methods for evaluating combined vibration. The aim of this study is to establish an evaluation method for tri-axis traffic vibration. Sensory test using a shaking table which can vibrate simultaneous tri-axis was conducted, and relationship between human sense and vibration was examined. As a result, a performance value C_(1/√2:1:1)VLT_(630ms,60dB) that relative to human’s vibratory senses were established: C_(1/√2:1:1)VLT_(630ms,60dB) is calculated by the maximum value of the level value combined from accelerations in three directions and the duration of the level over 60dB.

In recent years, much attention has been focused on the development of neurophysiology-based models as a new way to evaluate visual environment. In our previous paper, we proposed a method for evaluating the visibility from an edge detection algorithm. In this study, we incorporate chromatic mechanism into existing algorithm in order to make it applicable to a greater variety of spaces with colors. The results of the subjective experiment conducted in a model space showed that the visibility could be well estimated by the algorithm proposed in the research.

Based on NASA’s satellite observations, we created nationwide ozone data from 2005 to 2022. Using this ozone quantity, UV-B values were calculated by Igawa’s ultraviolet model and compared with the observations by JMA. As the calculated values were approximately 30% larger than the observed values, we investigated the reason of the difference and proposed the correction method of the model. The UV-A calculations obtained by Igawa’s model were also compared with the UV-A observations by the UV Monitoring Network which was active from 2000 to 2021. The results showed that the calculations were approximately 17% larger than the observations

Bird et al.’s spectral solar irradiance model, Spectral2, accurately estimates spectral solar irradiance for clear skies. Since the model estimates spectral solar irradiance for global as well as direct and diffuse, it can easily be extended to the spectral irradiance calculation for tilted surfaces with various azimuth. This paper describes a method for extending Spectral2 to all-weather conditions. We use data observed at Tsukuba and Naganuma in 2015 from NEDO's database for the extension and examine the accuracy including observed data at Gifu, Tosu and Okinoerabu. We name the proposed model Spec_allsky.

This study aimed to clarify the concentration at which skatole’s odor quality begins to change and its characteristics. Olfactory thresholds were measured using the triangle odor bag method, and the odor quality of samples identified as odorous was evaluated.

As a result, the average olfactory threshold was determined to be 7.3×10^⁻7 ppm. At an odor concentration of 3, the odor quality of skatole was observed to shift from light and mild to heavy and cloying. An odor concentration of 3 was designated as the recommended level corresponding to a 20% unacceptability rate, as defined by the AIJES odor guidelines.

This study clarifies how differently toilets, which are sanitary fixtures, influence the generation and spread of droplets and aerosols at the time of flushing, depending on the flushing method, the structure and the fixture discharge characteristic values. The study also aims to establish, on the basis of the clarification results, conditions for toilets which would enable the suppression of droplets and aerosols, and to acquire knowledge conducive to the designing of hygienic toilet spaces with infection prevention in mind.

We proposed a system that provides seat recommendations or air conditioning feedback based on user reports such “hot” or “cold.” This system was validated through experiments and simulations. As a result, we confirmed that control logic ensuring temperature variation, minimizing seat changes, and considering thermal dynamics significantly improves satisfaction. Additionally, we found that using large language models (LLMs) is crucial for considering various qualitative factors. Based on these insights, we developed a system integrating LLMs and deep reinforcement learning (DRL), which improved overall satisfaction by 31–35% compared to steady-state operation.

In this study, we investigated about supercooling of erythritol, and modeled the supercooling, and incorporated it into a one-dimensional unsteady heat conduction calculation, and conducted unsteady heat conduction experiment and verification. Consequently, the model was confirmed to be approximately valid. In addition, we incorporated the model into the heat transfer simulation model for latent heat storage tank, and conducted the experiment of latent heat storage tank of cylindrical capsules and verification. As a result, although this supercooling model was able to capture the trend, it was not a sufficiently accurate verification experiment.

In this study, we report on the operational adjustment process for air conditioning system using thermos-active building system. Annual operation settings were established throughout the building’s first year of operation. Indoor environment after system adjustment was evaluated based on the measurements and the results of a questionnaire survey of workers. By examining long-term operation records, long-term characteristics in slab temperature transition were extracted, and notable human errors in operating were discussed.

In this study, we aimed to understand the power consumption in the common areas of apartment buildings and to create basic data for considering energy conservation measures. We measured the power consumption of various equipment and clarified the relationship between equipment capacity and power consumption. The findings are as follows. 1)The power consumption in common areas of apartment buildings is greatest for electric light, followed by disposers and water pumps, which account for most power consumption. 2) Equipment capacity and building attributes show a relatively high correlation with power consumption.

This report provides an example of the calculation of embodied carbon for a research facility that has achieved 『ZEB』, based on international standards, specifically for air conditioning and plumbing systems. The result of the embodied carbon calculation for air conditioning and plumbing was 5.82 kg-CO₂e/m₂year, or 12.8% of the total embodied carbon of the building. Refrigerants also accounted for a large share, 69.8%, of the total EC for air conditioning and plumbing. To provide example to be compared, embodied carbon calculations were also performed for general buildings.

Online questionnaire survey was conducted to clarify the influence structure on workplace productivity. Based on the survey results, a workplace productivity model was constructed by structural equation modeling. The hypothesis that environmental, communication, and work factors lead to intellectual activity through the ease of relaxation and concentration was proposed. Total effect of impact on “workplace productivity” was significant for “relaxation,” “job fulfillment,” and “concentration.” For main workers who are mainly engaged in intellectual processing and knowledge creation, an environment that facilitates concentration was important, while for those who often spend time on information processing and relaxation, job fulfillment was essential.

In this paper, changes in electricity, gas and water consumption associated with behavior change triggered by COVID-19 pandemic were ascertained using measured data and a questionnaire survey of living conditions at two apartment buildings in Tokyo area. The results showed that (1) consumption during weekday daytime increased significantly just after the pandemic, with delayed morning and advanced evening peaks, (2) annual energy consumption in FY2020 considering the yearly difference of outdoor temperature increased remarkably compared to before the pandemic, and (3) the evening peak shift was observed even in FY2023, indicating that some pandemic-induced behavior changes had become well-established.