A model for predicting fire behavior in a compartment is formulated that considered the following two points regarding mass loss rate: (i) the heat transfer from flame to fuel is decreased with lack of oxygen concentration; and (ii) the heat transfer from walls, ceilings and smoke layer to fuel with development of compartment fire. In addition a computer simulation model based on zone concept is developed that considers conditions in a compartment from the initial period to the decay period of compartment fire. Namely, this approach applies a two-layer zone model for the growth or pre-flashover stage and a one-layer zone model for the fully developed or post-flashover fire. The compartment fire experiment is performed to validate this model. In general, good agreement between experimental and theoretical results about the mass loss rate and the temperature in the compartment is obtained.

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The reduction of residential fire deaths is achieved not only by popularization of fire protection equipment such as smoke detectors and/or residential sprinklers, but also by many other efforts such as improvement in fire safety of appliances and popularization of fire-resistive construction in homes. The authors believe that preventing fire ignitions and mitigating fire damage through passive fire protection measures are both effective and fundamental approaches to reduce future fire deaths in addition to active fire protection systems. Therefore, we are working toward examining the availability of various measures that would reduce residential fire fatalities in high-risk groups. For this purpose, two main kinds of data sources were used in the analysis to see the relation between attributes of residents and houses and fire death risk in residential fires. One is the national database of fire incident and fire fatality reports collected by the Fire and Disaster Management Agency. The other source is the housing survey database with data such as age of residents, type of household, type of house and structure, and so forth. As a result, we found housing conditions such as type of house and structure are significantly relating to the fire deaths risk in residential fires together with the attributes of victims such as physical capability and/or age.

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This paper aims to find the preferred combinations of illuminance and color temperature under RGB LED lighting in living rooms and to compare them with those found in the previous research under RGB fluorescent lighting.
Subjective experiments were carried out using scale models illuminated by RGB LEDs with the dimmer. “Preference” and “Brightness” were evaluated as the scenes of “Relaxing” and “Getting together”. 25 combinations which consist of 5 illuminances (50lx, 100lx, 200lx, 400lx, 800lx) and 5 color temperatures (300K, 3500K, 4200K, 5000K, 6500K) were investigated. Although the color rendering indices under RGB LED lighting were significantly lower than RGB fluorescent lighting, preferred combinations of illuminance and color temperature found were very similar to those under RGB fluorescent lighting.

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In this study we examined ventilation in summer and solar insolation in winter as elements of the indoor environment, with the objective of analyzing the seasonal characteristics of thermal environment evaluation as well as identifying how particular characteristics of space affect the evaluation of the thermal environment. The results were as follows. We found that in summer, feelings of discomfort disappeared even at the high indoor temperature of 33°C when a breeze of at least 0.6 m/s was present. In winter, some subjects expressed a desire for the temperature to be raised while others desired it to be lowered, with a neutral temperature of 23-25°C. We found that subjects' degree of satisfaction to exposure to sunlight was “just right” at temperatures over 25°C, with dissatisfaction at the amount of sunshine being eliminated. During winter, by moving into and out of sunlit areas, subjects created a transient thermal environment in which they actively enjoyed temporary pleasant sensations even in high temperatures.

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This study intends to set a habitability grade based on residents' consciousness on a performance level of environmental vibration.
A sensory test was conducted with forty subjects to investigate the relationship between habitability grade and physical quantity of vertical vibration of floor slabs. The subjects' answered to a questionnaire focused on views on habitability grade of environmental vibration before and after the test. Results of the sensory test and the consciousness survey show that the habitability grade of floor vibration can be set on the basis of perception probability. The authors propose a new habitability grade of floor vibration based on the A.I.J. Guidelines in consideration of this relationship between habitability grade and perception probability.
This study determines specific meanings of habitability grade of environmental vibration based on residents' consciousness, such as a standard level and a request level of a majority of people.

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This study aims to clear the effect of view components on evaluation for window faculties related to visual environment in family room. It is assumed that the ultimate evaluation for window in family room consists of five faculties; “day-lighting”, “visibility of view”, “comprehensibility of outside”, “part of interior”, and “protection of privacy”. Furthermore, it was extracted five view components; ‘sky’, ‘ground’, ‘wall’, ‘window’, and ‘green’. In order to examine the effect of each area rate of view components on the evaluation for each window faculty and ultimate evaluation, a subjective evaluation was carried out. It was shown that the evaluation of each window faculty was related to one or more view components.

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In the current air-conditioning load calculation, the relation between air-conditioning load and thermal sensation of the resident is uncertain in design stage, because the air-conditioning load is calculated regardless the thermal sensation of resident. This paper showed a new air-conditioning load calculation method that considered the thermal sensation of the resident. The results of case study are the following. 1) The new load calculation method can calculate air-conditioning load for a function of the resident thermal sensation. The results of case study showed the new load calculation method has high load more than 20% in comparison with the current load calculation method. 2) In this new load calculation method, the heat extraction rate from indoor air or walls is calculated as air-conditioning load to maintain thermal sensation of the resident. 3) In this new load calculation method, air-conditioning load changes by the position of the resident. The results of case study showed the difference became about 6%.

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There are two points of view for the prevention design of moisture problem in the building insulated envelope. One is the strictly prevention of high moisture condition in the insulated wall cavity. The other one is the permission of short-term high moisture condition, condensation and high moisture content of the wooden material as long as keeping physical durability. If the later standpoint were chosen, the insulated envelope design of every variety for Japan would be possible. Nevertheless, there are no criteria to estimate the damage of physical durability of wood by the biological factors related high moisture condition. In the previous paper, we reported about the concept of the prevention design of moisture problem in the building insulated envelope and the relationships between water content and decay various woods under hygrothermal steady conditions. In this paper, the relationships between water content and decay of various woods under two kinds of hygrothermal transient conditions are shown.

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The purpose of this study is to clarify the effect of the passive environmental control methods in the traditional vernacular of Taketomi Island, a small village in Japan. The indoor thermal environment for building scale and the effects of thermal environmental relaxation and windbreaking for district scale are analyzed based on field measurement. The following results were obtained: 1) Windbreak, that is, shelter belts around the village decrease the wind velocity in the village. On Taketomi Island, numerous typhoons pass through every year, so this windbreak defends the houses from the strong wind. 2) Alleys covered with the white sand are superior in the thermal environment compared to the alleys of asphalt and concrete pavement, and also stone walls made of coral are superior to the walls made from reinforced concrete in this thermal environment. 3) In summer, the thermal environment in traditional vernacular houses is by no means comfortable, due to the change of architectural forms and resident's life styles. Indoor air temperature of the houses is higher than that outside during the day.

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Groundwater heat pump (GWHP) systems can achieve the higher coefficient of performance (COP) and more energy-saving than the conventional air-source heat pump (ASHP) systems. The performance of GWHP system significantly depends on conditions of groundwater and thermal properties of underground. For the optimum design of a GWHP system, it is necessary to comprehensively consider them and building conditions. In this research, heating and cooling experiments with real-scale experimental equipments have been conducted to examine the performance of system. Furthermore, the feasibility study of GWHP system on two different conditions and three local sites has been performed by using heating and cooling load model in building. In the result, cost payback time of this system has been calculated and it has been found that this system is enough efficient in the site where heating and cooling load are balanced.

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In predicting flow rate of a cross-ventilated building, the conventional method using the discharge coefficient obtained from the chamber method and the wind pressure coefficient from a sealed model could underestimation. Authors aim to establish the prediction method of flow rate based on power balance within the stream tube inside and outside the building. In this paper, focusing the flow around the building, velocity, static pressure, and total pressure distribution will be shown by using PIV and rotatable to measure total/static pressure. In addition, those experiments are simulated by CFD because of its strength in determining the stream tube. In the last part of this paper, accuracy of CFD analyses will be shown.

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Although it is well known that carpets collect particles and other dirt and can be source of contamination of indoor environment, very little analysis have been done on the relation of carpets and indoor environment and cleaning effect of vacuum cleaners on floor carpets.
This paper made, firstly, theoretical analysis of collection and removal characteristics of vacuum cleaners on carpets, secondly, experimentally determined residual and collection rate of test dust on three types of floor coverings, two types of carpets and ‘tatami’, traditional Japanese floor covering, and, thirdly, deduced an equation to estimate the residual contaminants in the carpets.
The results show that 20 to 30% of contaminants is left in the structure of carpets after vacuum cleaning only. It is difficult to remove 100% of contaminants only with vacuum cleaning and necessary to use other methods such as washing with solutions for complete removal.

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In order to evaluate odor, the measurement method by olfaction is in common use. The various scales have been used for the odor sensory evaluation, for example, the intensity scale of Ministry of the Environment, one use by Yaglou, and one used by P.O.Fanger. These scales, however, have been used without any verification that these are interval scales or ordinal scales or neither of them. In this study, 8 kinds of intensity scales and 3 kinds of hedonics scales are discussed. Consequently the psychological distance between words for rating each scale and the difference between scales are made clear.

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This study aimed at investigating indoor air qualities of chemical contaminants for office buildings. This research carried out measuring volatile organic compound (VOC) concentrations with the passive method during office hours at 102 office buildings. From the 24-hour continuous measurement, VOC concentrations have a different tendency between air conditioning and non air conditioning time. The results indicated that the passive samplers should be exposed for 8 hours during air conditioning time. The formaldehyde and acetaldehyde concentrations of some buildings were higher than guideline values. One of the reasons for the guideline exceeds might be environmental tobacco smoke leakage from smoking space neighbor the office room.

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To investigate the effect of thermal environment and the ventilation rate on productivity, a subjective experiment was conducted. The conditions were the combination of thermal environment: operative temperature of 25.5°C and 28.5°C; and the ventilation rate: 11m³/(h•p) and 90m³/(h•p). Eleven subjects participated in a 350min exposure and worked on three-digit multiplication tasks for 180min. The percentage of dissatisfied with air quality was higher in the higher temperatures and in the lower ventilation rates. The performance of the task was not significantly different among the conditions. The increase of the level of fatigue was more in the higher temperature condition. Correlation between the percentage of dissatisfied derived from perceived air quality and the fatigue level was obtained. The relationships of the task performance and the satisfaction vote of the indoor environment and the level of fatigue were obtained.

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The aim of this study is to accelerate simulation software developments by abstraction of source code. ITermStructure the “interface” for a time period is developed to make complex term structure general. By using “Composite-Pattern”, all the concrete term classes which implement ITermStructure can be integrated into complex tree structure. By using “Generics”, specifications of schedules class shall not be specified until scheduler classes is declared and instantiated by a client code. Since the program code developed in this research and a code made by a client were separated clearly, developed scheduler classes is generally applicable for long term simulation programs.

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In this study, a subjective experiment was conducted in a climatic chamber to investigatethe effect of moderately hot environment on performance, fatigue, and especially the relationship between performance and fatigue. The climatic chamber was conditioned at operative temperature of 25°C (insulation value of 0.96clo), 28°C (insulation value of 0.96clo), and 28°C (insulation value of 0.61clo). Fourteen subjects were exposed in the environment for six hours. In this experiment subjects' performance at 28°C condition was lower than at 25°C condition, while they felt fatigue more strongly at 28°C condition than at 25°C condition. Besides, correlation between personal rates of complaints of fatigue and performance in z-score was observed with correlation coefficient of -0.72. From the linear regression model, increase in 10% of fatigue corresponded to the decrement in z-score by 0.083point.

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The reuse system mentioned in this paper is an overall system for realizing a reuse business in a cyclic of process in a reuse flow, namely, design, fabrication, construction, maintenance, dismantling, and storage. Here, we take up Rolled H-section steels. It is easy to handle them as reusable members because of manufactured in accordance with Japanese Industrial Standard. We propose reuse business model in order to circulate reusable members called securitization and asset based lending using integrated circuit tag in the view point of fund procurement. Then, economic condition of reuse business model is evaluated through cost simulation.

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