The ignition temperature of the combustible that received the radiant heating was measured with corn calorimeter examination device. The specimens were seven kinds of wood, one kind of painted wood, and four kinds of building materials. As a result, it has been understood that the surface temperature for piloted ignition that measured using cone calorimeter was 300℃ to 400℃, which was 10-100℃ higher than the flash point.

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Based on the actual measurement results covering a period of approximately twenty-seven months, we have clarified the indoor thermal environment and energy consumption characteristics of a well-insulated and airtight residential house, located in a temperate region. We have also made clear the potential for further energy savings. The key points are as follows: (1) Heating starts when the daily average outdoor temperature falls to 15℃ or lower, and measured values for the coefficient of heat loss and energy consumption efficiency, heating of the house, were similar to the original specifications. (2) When the daily average outdoor temperature ranges from 15 to 25℃, neither heating nor cooling is required. (3) Cooling starts when the daily average outdoor temperature exceeds 25℃ and the energy consumption for it can be kept low even in fierce heat. (4) For further energy saving, it is important to optimize the air-conditioner capacity according to air-conditioning load. At the same time, in a temperate region where humidity is high in summer, the selection of optimum dehumidifying methods is important.

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Recent lines of research show that light is important not only to human vision but also to human circadian regulation. The photometric quantities based on the relative photopic luminous efficiency function are used to express lighting condition. However it has been shown that the spectra sensitivity curve for circadian regulation is different from the spectra sensitivity curve for the photopic visual system. In order to support lighting design considering circadian regulation, in this paper, a method to evaluate light based on melatonin suppression, one of circadian rhythms, was proposed. A formula, using spectrum distribution of radiant flux and action spectrum of melatonin suppression shown in a previous study, was developed to calculate the effect of light on human circadian regulation. Also a simplified formula was proposed in which illuminance and color temperature were used. The applicability of the simplified formula to actual spaces was tested by measuring light from lamps, the sun, and computer display and light in houses.

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Cross-ventilation mechanism with large openings is different from one with small openings. The kinetic energy occurred at the windward opening interfere with the airflow characteristic of the leeward opening. The effect depends on opening conditions. In this paper the correlation between airflow characteristics and the opening area ratio and relative locations is studied through wind tunnel experiment and CFD. It is concluded that the airflow characteristics could be divided to three cases by the ratio of opening area (A_L/A_W) and the airflow angle to windward opening (β). In the case of A_L/A_W ≪ 1, the airflow is dominated by static pressure. In the case of A_L/A_W > 1 and β≒0, the airflow characteristics is defined by only windward opening shape. In the other cases, the airflow is influenced by both of kinetic energy and static pressure.

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The purpose of this paper is to quantitatively determine the removal performance on cedar pollen of domestic air cleaners which have widely been utilized in ordinary houses. Five domestic air cleaners were tested in an experimental chamber, using cedar pollen and the JIS Test Powder. The evaluation were made with an index of equivalent clean air rates (ECAR). The results showed that the removal rates of cedar pollen were 19.12〜180.2(m^3/h) for 0.3μm particles, and 18.7〜213.0 (m^3/h) for 0.5μm particles except for one type and with JIS Test Powder 20〜50(m^3/h) for all type of domestic air cleaners. The pollen has smaller particle portion than the JIS Test Powder No.11 and the performance of cleaners cannot be estimated simply from the morphological size distribution of the test aerosols. The analytical prediction of pollen concentration were made and compared with the results of experiment to show a fairly good fit for particles smaller than 1μm.

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This paper reports the results of test chamber experiments and the estimation of mass accommodation coefficient of ozone to solid surfaces. The test chamber had one supply inlet and one exhaust outlet, with a cavity of dimensions 2.0m (x)×0.3m (y)×0.01m (z) in which a two-dimensional flow field was developed. A laminar flow field was developed in the test chamber. In order to discuss the order of wall surface deposition for ozone, the concentration reduction of ozone in the test chamber were measured. Furthermore, to estimate the mass accommodation coefficient, which represents the deposition ratio of ozone to solid wall surface, numerical analysis corresponding to the experimental conditions and with a built-in deposition flux model that include mass accommodation coefficient were carried out. The estimated value of the mass accommodation coefficient for ozone to solid wall surface ranges from 2.3×10^<-6> to 8.7×10^<-6> [-] under temperature conditions of 293 [K].

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In this paper, a test method for evaluating the ability of adsorptive building materials to reduce the concentration of formaldehyde is examined. The authors developed a new method that uses a small chamber to test the suppressive effect of adsorptive building material on formaldehyde-emitting materials. Two small chambers are prepared, with the formaldehyde-emitting building material placed in one chamber, and a composite building material comprised of adsorptive building material and the same kind of the formaldehyde-emitting building material in the other. The formaldehyde emission factors of the two chambers are compared, and the equivalent ventilation rate Q_<ads> is calculated. This test method enables the indoor concentration reducing performance and the suppressive performance of the adsorptive building materials to be evaluated at the same time. The tests of the suppressive effect are examined using several kinds of adsorptive building materials, and accordingly the validity of the test method is verified.

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In order to clarify the mechanism of indoor air pollution with semi-volatile organic compounds (SVOC), it is important to accurately measure the emission rates from building materials and products. The authors have already reported the thermal desorption test chamber method (TDC method) that can measure the emission rates of SVOC from test pieces of materials with certain accuracy. In this study, we evaluated the reliability and accuracy of the TDC method from the various points of measurement procedures. In these evaluations, it was found that the accuracy of the measurement depends on the configuration, volume, and inertness of the chamber.

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This paper presents measurements of SVOCs (semi-volatile organic compounds) emitted from building materials, household electric appliances, and products in a room. Until now many reports have been published on the emission test chamber method for measuring VOCs (volatile organic compounds), whereas there are very few reports on the measurement of SVOCs In this paper, we apply the thermal desorption test chamber method that we developed to measurements of SVOCs. This method can measure correctly the emission rate of SVOCs emitted from materials under actual room air temperature conditions.

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Subjective experiments with a desktop based task conditioning system were carried out to investigate the benefits of system in an office like chamber. The experiments were conducted under three different combinations of ambient air temperature and relative humidity, (1) 27℃/40%RH, (2) 30℃/40%RH, and (3) 30℃/70%RH. Each of 16 college age subjects was exposed to the three different experimental room air conditions. There were six supply air flow patterns for task air conditioning, which parameters included isothermal air flow and non-isothermal airflow with three different air velocities. Setting of task condition was fixed at first, and then the subjects were allowed to control the environment freely after certain period in the subjective experiments. Thermal sensation, airflow sensation, and other variable were investigated. The way the subjects controlled the task system was also monitored. It was considered that the task conditioning system could keep subjects thermally comfortable with their ambient temperature higher than condition without it. Questionnaire responses under the 'preferred air' condition revealed the importance of adjustment of task conditioning.

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In large enclosures such as gymnasiums, it is difficult to control air temperature in the occupied zone comfortable in heating condition. There are two main reasons that air temperature in an occupied area is not increased efficiently in large enclosures. 1) A hot supplied air goes up and stays upper area due to buoyancy and it takes long time to reach lower occupied area. 2) Heat capacity of building structure disturbs to increase air temperature and cold air stays lower area. In this paper, the field measurement is presented in which the under floor return air system is applied to the gymnasium to resolve these problems. The CFD simulations coupled with the control simulation of the supply air temperature are also demonstrated and the details of temperature distributions and time dependence are discussed.

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This paper proposed two types of heating design weather data, the t-x basis data and the t-Jh basis data. They were produced from the weather values on the extreme-weather days selected out of Expanded AMeDAS weather data from 1981 through 2000 using the two weather indices. The extremity of the proposed design weather data were evaluated obtaining the cumulative frequencies of occurrence of the daily weather values and the probabilities of occurrence of the thermal load exceeding the heating design load calculated with the proposed weather data.

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This study examined a method of producing two types of cooling design weather data sets based on the daily total of solar radiation and the daily mean of outdoor air temperature. The design weather data sets were produced for three cities and their severity were evaluated by investigating both the frequency of occurrence of the daily weather value and the possibility of occurrence of the thermal load exceeding the design value calculated with the proposed design weather data.

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In the rapid penetration of advanced and highly networked information society, it is necessary to assure the safety of computer systems at the wide-area disaster in the inner city district of Tokyo. We examined distribution and concentration of computers that take the important roles in business activities and administrative activities from introduction records. They stand evenly on intensity 6 upper and intensity 6 lower ground of the earthquake intensity map and we found comparatively high concentration around the representative business district of Tokyo. This result is that it is important to make infrastructures secure and to enhance the credibility of infrastructures of the representative business district of Tokyo would contribute to assuring the safety of computer systems at the wide-area disaster in the inner city district of Tokyo.

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This research attempted to analyse the thermally distributed flow by using the Schlieren image. By arranging two dimensional building models with heating floor, thermally distributed building canopy space was established in the wind tunnel. In the Schlieren images, dense color zones, which show the existence of steep temperature distribution according to the principle of Schlieren were observed at the top of building canopy and near the ground surfaces. The same tendency was verified in the temperature measurement data of the wind tunnel. This research also indicated that temperature distribution inside the wind tunnel could be quantified with high precision by the Schlieren image analysis, applying the quadratic function of brightness.

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Integrated panel coated with the super-hydrophilic photocatalyst can spread water film on the surface and evaporate water efficiently. This paper demonstrates the efficiency of the cooling effect obtained by the observations with the actual scale model. The following remarks may be given. (1) The heat balance formula on the outer wall surface to calculate surface temperature and released heat is shown. (2) The predicted value agrees well with the measurement. (3) The parameters in the formula were obtained through the experiments under the various weather conditions.

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Thermal environment was measured at six spots with different tree species and layered structures in National Government Showa Kinen Park and evaluated by MRT and CSE. The results were as follows. 1. CSE was large in double-layered forests of high trees and small in single-layered forests and MRT was low in both. 2. A variance analysis of CSE of different sunshine hours was performed for the variance factors of Forest type and the time of the day. The result revealed that both were significant at 0.1%. Forest type showed a particularly marked effect, which was large on fine days and small on cloudy days. 3. A regression equation to calculate CSE and MRT from verdure was examined, an equation to predict CSE was obtained, which expressed with Ratio of tree crown shadow to give R^2&ge;0.84, and an equation to predict MRT was obtained, which expressed with green leaf factor (GLF) to give R^2&ge;0.88.

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Aliasing phenomenon in Computer Graphics images and animations is serious problem to lose quality. Techniques to solve the problem, namely antialiasing technique, have been researched and developed, but these usual techniques have weak point to consume much calculation time. This paper proposes a new antialiasing algorism that keeps image quality and speeds calculation up. Applying different antialiasing method to each step at rendering process, namely finding visible object, shadow casting, mapping, and reflecting, is main strategy of the new algorism proposed here. Appropriate different method for each step can optimizes image quality and calculation time.

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