Temperature and moisture content of 2-hour rated fire-proof timber beam with partly treated wooden protective layers were measured at a furnace test consisting of 2-hour standard heating and 24-hour natural cooling. Air-dried and completely-dried specimens were used. Refractory moisture content probes developed by the authors were used. The results generally reproduce the typical feature of the influence of the phase change on the moisture movement within the wood, yet leaving some uncertainty in the precision. Mechanical properties estimated based on the measurement suggests considerable impact of initial moisture content on the mechanical performance of beam.
The authors conducted an online survey in Japan in March 2019 (N=2,684) to gather feedback from workers who commute to their offices and work with several people in a corporate environment. However, considering the COVID-19 pandemic changed our workstyle, a second survey (n=490) was conducted in December 2020 for workers whose offices remained mostly unchanged since the last survey to compare data from both surveys for the same respondents and investigate the changes in the value of office spaces. The result suggested that the survey respondents were influenced by the changes in workstyles and attitudes in the telework experience.
While surrounded by a built environment, various interpersonal cognitions and behaviors such as impression formation, communication, and cooperation are regulated and executed. It has become clear through many years of environmental psychology studies that the physical environment not only surrounds but also implicitly influences interpersonal cognition and behavior. This paper reviews the literature on the effects of visual environmental factors specifically brightness, color, and depth on interpersonal cognition and behavior in a little more than 20 years, clarifying the achievements and expansion of the research area, the challenges to be overcome, and the outlooks for the future directions.
The purpose of this study is to examine the relationship between “visibility from inside” and “estimated visibility from outside” and the factors that affect “visibility from inside” in various lighting environments and windows in order to predict visual privacy. From the results of experiments in actual housing complex and the laboratory, it was found that the linear relation between “visibility from inside” and “estimated visibility from outside” was established for all types of window treatment. The relationship is unaffected by lighting condition, window shape, or evaluation position. However, this relationship is only valid when the outdoor illuminance ≥ indoor illuminance.
In this research, the author proposed a supercooling phenomenon reduction PCM that suppresses the decrease in latent heat by installing a PCM with a small supercooling degree on the heat transfer surface side of the PCM with a large supercooling degree. As a result, it was shown that the supercooling phenomenon reduction PCM can reduce the supercooling degree by forming and growing solidified crystals even when the temperature is higher than the supercooling release temperature. Furthermore, the calculation results for predicting the cooling and heating characteristics of the supercooling phenomenon reduction PCM were in good agreement with the experimental values.
From an economic point of view, it is expected that airflow-screen façade will be adapted to Green building. Therefore, there is a need for a practical thermal load simulation model that can evaluate various airflow-screen façades systems and can be used in mechanical design work. In this paper, using NewHASP and ventilation network program, a multi-space model of the entire airflow-screen facade system consisting of glazing, an air layer between the glazing and the venetian blind, airflow cavity and rolling screen is proposed. And we clarify the effect of rolling screen air permeability on thermal performance of airflow-screen.
Double skins are an effective technique for achieving ZEB. In this research, we will use meta-simulation and AI to construct a general-purpose blind control that can minimize the energy consumption of lighting and air conditioning when daylight is used. First, we built a simple double-skin meta-simulation model to clarify the thermal performance and energy consumption performance when various kinds of blind controls are performed. Next, we performed machine learning and element analysis using AI with the simulated result. Then, we clarified the most effective parameters on thermal performance and energy consumption performance.
When alcohol is applied to wooden surfaces, the amount and composition of released substances and secondary products influence the perceived air environment. This study aimed to determine the effects of applying alcohol to indoor wood surfaces on volatile organic compounds emissions and perceived air quality. The perceived air quality in the room deteriorated and the odor rating decreased when cleaning work was performed indoors with 130 mL/m2 of alcohol applied to unpainted wood interior and furniture surfaces. Furthermore, the airborne concentration of acetaldehyde was detected more than the indoor guideline values.
The purpose of this study was to develop a method for estimating the energy consumption of residential CO2 refrigerant heat-pump water heaters. This paper considered a calculation model involving the use of actual machine data analyzed in Part 1. It was evaluated by considering the effect of efficiency losses on the ideal system COP. The calculation model estimated "heat-pump COP", "storage heat loss" and "auxiliary power loss". The developed method was applicable to wide-ranging hot water supply conditions. The estimation and test values of the system COP agreed to within a tolerance of around ±0.2.
This paper describes the analysis of cooling operation data for an office building with multiple air-conditioning heat sources, and the estimation of energy saving effect of cooling water temperature relaxation.
1. BEMS data of an office building in Tokyo was analyzed to reveal the cooling operation of the air-conditioning heat source. Furthermore, chilled water temperature characteristic equations were created.
2. A study using a simulation model of the heat source that incorporates the chilled water temperature characteristic equations confirmed that more energy-saving potential from further relaxation of the temperature for the mid-term period.
As the trend toward a decarbonized society accelerates, Net Zero Energy Houses are expected to become more popular. In recent years, the residential sector has been facing the problem of inadequate adjustment of power supply and demand due to the expansion of renewable energy installations.
The objective of this study is to understand the actual situation of energy consumption and electricity supply and demand in Net Zero Energy Houses. The primary energy consumption of all-electrified and gas-combination ZEHs were compared. In addition, the relationship between house attribute, occupant lifestyle, and primary energy consumption of all-electrified ZEH were analyzed.
This study aims to identify factors that need to be improved to enhance work efficiency of workers in both office and home environments by focusing on activities classified into communication and intellectual ones. In this study, questionnaire surveys were conducted in four buildings. From results of questionnaires, ease of communication and intellectual activities are ensured in office work. Each activity has an equal impact on work efficiency of office workers. In work from home, ease of intellectual activities also has a stronger impact on work efficiency than ease of communication activities, and intellectual activities are easy.
Partial insulation retrofitting is an effective method for improving thermal insulation in existing houses as its construction cost is lower than that of total insulation retrofitting. This study aimed to clarify the actual conditions of the thermal environment in partially insulated retrofitted houses in summer and winter. Furthermore, the size of insulated areas and heating methods were examined from perspective of energy consumption and health. Field surveys on indoor environments were conducted in an actual partially insulated retrofitted house in Chiba prefecture. Subsequently, we show the effects of different insulation areas and heating methods on energy consumption and health.
Today, the demand for telework is increasing, and the use of non-face-to-face office work is more common. However, dissatisfaction with the loss of productivity in non-face-to-face work is an issue. As a cause of dissatisfaction in non-face-to-face communication, it is indicated that there is a lack of “noticing the existence, actions, and feelings of collaborators without strain” (awareness), which was common in face-to-face communication. Therefore, we conducted a web-based questionnaire survey of teleworking office workers on factors that contribute to productivity in non-face-to-face work. Our results showed that awareness of voice in non-face-to-face work needs improvement.