Fire plume ejected from an opening tend to have a central axis of air current that rises closer to the wall surface as the cross-sectional shape of the opening (hereinafter , horizontal opening) becomes more horizontal. Fire plume ejected from such openings increase the potential risk of fire spreading to upper floors. Furthermore, fire plume from an opening may become longer due to increased thermal decomposition of combustible materials inside the compartment and the effect of pyrolysis gas burning outside the building.
 Currently in building design practice in Japan, the method proposed by Yokoi is generally used when investigating measures for preventing the spread of fire to the upper floors due to fire plumes from openings in buildings. However, the opening conditions that Yokoi examined covered aspect ratios n = 2W/H (W: width of opening; H: height of opening) of up to around 6.4, whereas the openings in modern buildings may have openings with aspect ratios greater than 6.4. Furthermore, although the amount of pyrolysis gas emitted from the opening is expected to increase with increased amounts of flammable material brought into the building, the Yokoi method is unable to take into account such changes in the amount of pyrolysis gas.
 The focus of this research was therefore placed on the shape of the plumes of hot air under various flammable material conditions for openings with a horizontal shape. A series of experiments using a full-size compartment focusing on the shape of the temperature distribution in order to obtain knowledge related to the shape of the temperature distribution were conducted.
 In the experiment, we aimed to determine the temperature distribution above horizontal openings with aspect ratios of n = 5~20. The experimental apparatus consisted of a combustion compartment and a facade for modeling a room on fire. The dimensions of the combustion compartment were 4000[mm] wide × 4000[mm] deep × 1700[mm] high. The shape of the opening was fixed with opening widths of 2[m] and 3.7[m], and the opening aspect ratio was set in the range n = 5~20 in six sets of conditions for the opening width of 2[m] and three sets of conditions for the opening width of 3.7[m]. Three different fuels were used for the heat source: methanol, ethanol, and heptane.
 The following was found from this study.
 · Temperature attenuated with height Z above the opening to essentially the -1 power, the same as the gradient of the temperature distribution of the rectangular heat source.
 · The temperature distribution near the wall above the opening, nondimensionalized by taking T^* for the vertical axis and Q^*_(H-Zn)^-2/3z_(H-Zn)^* for the horizontal axis, exhibited a correlation with the temperature distribution of the rectangular heat source in free space when using the amount of heat Q_ef generated by pyrolysis gas.
 · Q_ef,max may underestimate the amount of heat generated by the pyrolysis gas. When Q_ef,crit was used, under the conditions where ethanol and heptane were used, the calculated and experimental values tended to match well.

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 Strategy for the development of wooden fireproof structural elements based on the sacrifice-layer concept through bench-scale tests is studied through a series of bench scale tests on the design composed of sacrifice layer (chemically untreated wood), barrier (fire retardant treated wood) and loadbearing part (untreated wood). It has revealed importance of the design of the sacrifice layer to reach the glowing combustion temperature at around the end of the heating for the achievement of self-extinguishment. It has resulted in the development of Japanese-cedar based 1-hour fireproof beam only with small test apparatuses available almost everywhere, demonstrating its advantage for the technical development in the districts not accessible to large furnaces.

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 The purpose of this study is to estimate the airborne sound insulation performance of partition walls with cross laminated timber panels (=CLT panels). Results of sound insulation experiments in the laboratory are as follows.
 (1) In case of a partition wall without slit between CLT panels, its sound transmission loss increases monotonically to frequency up to 3150 Hz band. Regression line formula is applicable in this frequency range with a high correlation coefficient.
 (2) In case of partition walls with narrow slits between CLT panels, effect of sound transmission through the slits is not negligible. Especially in frequency range over 500 Hz band, decrease of sound transmission loss appears remarkably compared to the case of no slit. However, this decrease is predictable by a formula with the total length of the slits.
 (3) If improvement of the sound insulation performance is required, additional gypsum board wall or CLT panel wall on one side of the CLT wall is effective. This improvement effect will differ due to conditions of the slit between CLT panels and sound insulation materials inside the double wall constructions.

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 In earlier studies, we developed a PCM-plastered wall, which is a novel finishing material with a high thermal storage capacity. In addition, previous experiments by our research group have shown that the PCM-plastered wall significantly improves indoor environments and saves energy when an experimental module is used. In the present study, we developed a radiant heating－cooling hybrid system shown in Fig. 1 and measured its thermal performance. The indoor environment and the amount of energy saved from two experimental housings were also measured.
 First, as shown in Photo1 and Fig. 2, we constructed the hybrid system by combining a PCM-plastered wall and capillary tubing mats. We proposed a method for using the new system that combines natural energy for the effective use of the PCM through the application of a thin tube, which increases the contact area. In the summer, the system is used with a geothermal coil, whereas in the winter, solar heat obtained via a solar collector is effectively used. Fig. 3 depicts the renewable energy utilization.
 In the basic thermal performance test, the experimental device was installed in a room thermostat, and hot water from the refrigerant was circulated using a pump (Photo 3, Fig. 4 and Fig. 5). The temperature of the water, the surface temperature of the front and back of the PCM, and the surface heat flow on the PCM layer were measured in one-minute intervals (Fig. 6 and Fig. 7). The heat dissipation ability of the prototype was calculated from the difference between hot water and room temperatures, as shown in Fig. 8 to Fig. 10 and in Table1.
 Next, the basic thermal performance was tested using a geothermal coil to measure the heat storage and the temperature distribution of the soil. Photo 4 and Fig. 11 show the test device, which is a polyethylene pipe and a sensor installed inside the soil and covered with a heat insulating material. As shown in Table 2 and Fig. 12, the temperature was measured by a thermocouple, and an analysis was conducted by calculating two-dimensional non-steady heat conduction. Fig. 13 shows the temperature of the water, which was approximated by a sixth-order polynomial. Measurements results and analysis data were indicated that a position close to the pipe (30mm) was approximately the same (Fig. 14). All of the values approximately match after 30 hours.
 Finally, the energy savings and indoor environments were measured on the two experimental housings. The two buildings installed the hybrid system and geothermal coil. Table3 gives an overview of the experimental housing. The system diagram is shown in Fig. 16. Water is used as the refrigerant, and the heat source is a heat pump unit. The solar collector would be a secondary construction. One building is used by the office, and the other is a model house. Both buildings are in Sapporo, Hokkaido and plans for these buildings are shown in Fig. 17 and Fig. 18.
 In the summer, the room temperature of the N-project was stable and near the PCM melting point (Fig. 19). Even when the outside temperature reached 35 °C, P-project's room temperature remained approximately 26 °C. Therefore, it was confirmed that it had the cooling capacity required during the summer in Hokkaido (Fig. 20 and Table4). In the winter, the heating required for the experimental house is generally reduced to between 4% and 6% of the high thermal insulation and the significantly airtight house. It also demonstrated the reduction of the heating period. Furthermore, as shown in Fig. 21, Fig. 22, and Table5, there was a demonstrated decrease in heating. We confirmed, as shown by the graphs in Fig. 23 and Fig. 24, that the equivalent heat loss coefficient decreases owing to the PCM-plastered wall.

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 The Kamao tumulus in Kumamoto city, Japan is a national historic site and is generally not open to the public because of potential deterioration of its decorated chamber walls. The deterioration is attributed to the flow of water on to the decorated walls owing to dew condensation and rainwater infiltration; however, the wetting mechanism of the walls has not been sufficiently examined. Therefore, the purpose of this study is to investigate this mechanism and to propose the most effective preservation method. The following examinations were done to achieve the same.
 1. We analysed the temperature, humidity and wetting in the stone chamber using field surveys.
 2. We developed a three-dimensional heat and moisture transfer model for the mound and surrounding ground. We then validated the model and examined the cause of wetting by comparing the results of the model to the measurements of the hydrothermal environment and wetting behaviour in the stone chamber.
 3. We proposed an effective method for preventing dew condensation using a two-dimensional model that produces results similar to those of the three-dimensional model.
 The main results of the field survey are as follows:
 1. The decorated northern walls in the lower part in the burial chamber are dry in winter, whereas the entire surface is wet during summer.
 2. There is moisture on the ceiling and upper part of the northern wall in the burial chamber throughout the year.
 The main results of the case studies using numerical analysis model which was validated are as follows:
 1. Wetting of the walls in summer is attributed to evaporation on the ceiling because of the high temperature and dew condensation on the lower cooler part of the northern wall; however the location of these effects is opposite in winter. Rainwater infiltration is another factor that occurs throughout the year, causing the wetting of the walls.
 2. The main source of moisture responsible for the dew condensation in summer is the ventilation between the burial chamber and the entrance because of high absolute humidity and evaporation owing to the high outdoor temperature and solar radiation incident on the iron door.
 3. The most effective methods for preventing condensation in the burial chamber are to improve the ventilation during the dry seasons of autumn and winter, protect the iron door from the sun and insulate the mound in addition to waterproofing the ceiling in the burial chamber.
 4. The most effective methods other than improving the ventilation are shading the door and insulating the mound, as mentioned earlier; however, the dew condensation on the decorated chamber walls will still continue to occur in summer and can be suppressed either through cooling and dehumidification or only dehumidification of the stone chamber or through radiation heating of the stone surface.

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 Computational Fluid Dynamics(CFD) is classified by steady-state analyses and transient analyses. Since the computational cost of steady-state analyses is generally lower than transient analyses, steady-state analyses have been widely used to understand the flow field. On the other hand, because steady-state analyses are difficult to maintain high accuracy and unable to obtain transient data, transient analyses can be appropriate for the flow field which contains large time fluctuation. Since the separation flow around a building cause the complex flow field, transient analyses are likely to be competitive with the accuracy and information quantity when the accuracy of outside airflow which varies periodically and spatially is important.
 Previous studies have shown that Large Eddy Simulation(LES) is one of simulation methods of the transient analyses and can predict the airflow around a building with high accuracy. In LES, the velocity and pressure need to be separated grid the scale components and sub-grid scale components. However, LES which is applied the coarse computational grid resolution can give inadequate results from the viewpoint of the accuracy and information quantity. Therefore, understanding the scale of velocity fluctuation can be important before determining the grid resolution.
 Although there are many researches about the separation flow, there are not experimental data of time fluctuation scales which is influenced separation flow around a building. This paper focuses on the influence on the various fluctuation scale which generated by the separation flow. In this paper, the filtered velocity is obtained by applying spatial filters to the data of Particle Image Velocimetry (PIV).
 In order to understand influences of fluctuation scales on the separation flow, filtered velocity data are evaluated by the power spectrum, the averaged velocity, the Root-Mean-Square(RMS) of velocity fluctuations, the turbulent intensity, the branch points and the two-dimensional smagorinsky constant. The main concluding remarks of the present study are as follows.
 1) As the spatial filter becomes bigger, power spectrums are overestimated above 100Hz at X^*=-0.45, 0, 0.45 on Z^*=1.104 and are underestimated below 20Hz at X^*=-0.45, 0 on Z^*=1.104.
 2) The averaged velocity, the RMS of velocity fluctuations and the turbulent intensity approximately match with CASE_F1 and CASE_F3.
 3) The spatial size of about 50% of vortex flow which occurring on the upstream side from X^*=-0.2 is smaller than the filter size of CASE_F3. Moreover, The spatial size of about 60% of vortex flow which occurring on the downstream side from X^*=-0.2 is bigger than the filter size of CASE_F9.
 4) The smagorinsky constant is influenced by the filter size and has irregular distribution in the measuring area of PIV.

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 The Impinging Jet Ventilation System is an air-conditioning method to form thermal stratification. The final objective of this work is to establish a simplified prediction method of vertical temperature profile. As a numerical experiment, a parametric study on supply air momentum is first conducted by CFD in this paper. Based on those results, appropriate turbulent thermal diffusivity in the Block Model corresponding to the supply air condition is determined, because it is of great importance on vertical temperature distribution. The correlation between key dimensionless number regarding important design conditions and the turbulent thermal diffusivity are finally shown.

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 Particulate matter (PM) adversely affects human health. Even though PM tends to consist of higher concentrations outdoors, indoor PM concentrations should not be overlooked, given that people spend most of their time indoors. When there is no strong indoor PM source, indoor concentrations change within a certain ratio following the diffusion of outdoor concentrations indoors. The Indoor/Outdoor (I/O) concentration ratio is affected by static building properties such as airtightness, ventilation system type, and the system's air filter performance. However, natural ventilation can have a dynamic influence on the I/O ratio because of significant changes in ventilation rates and flow patterns within the building.
 This study measured PM concentrations for particles ranging from 0.3 to 10 μm in size. The study was conducted in a room of an office building in Tokyo, over a three-week period. The size ranges were divided into 16 channels and 10-min averages of the number of particles at each channel were measured using an optical particle counter. Occupants in the room utilized natural ventilation by manually opening a window. The window was opened and closed twelve times during the entirety of the measurements.
 Because outdoor PM consisted of higher concentrations than that found indoors, the natural ventilation lead to larger Indoor/Outdoor (I/O) concentration ratios. The PM concentrations were observed to increase and decrease just after the window was opened and closed, respectively. These concentration changes were more remarkable for PM consisting of larger particle sizes. Where PM measured 10 μm, concentrations increased 8 times after opening the window and decreased 0.5 times after closing the window on an average hourly basis.
 Particle-size is a factor for concentration changes caused by natural ventilation as discussed using concentration prediction based on the mass balance equation of indoor PM. As a result, the dependency was explained quantitatively in terms of the difference in the gravity-settlement velocity of the particles. Using ventilation parameters estimated in this analysis, the I/O ratio of PM concentration as a function of the particle size was predicted. During natural ventilation, indoor PM consisting of particles smaller than 1 μm can have the equivalent concentration of outdoor PM. However, particle size increase leads to a larger gravity-settlement velocity and lower I/O ratio. Therefore, particles measuring 10 μm are predicted to have an I/O ratio of 40% in accordance with the room analyzed in this study.

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The authors have proposed an air-conditioning system utilizing under-floor chambers and currently available commodity products such as domestic electric air-conditioners. In an existing detached house which is highly insulated and equipped with the system, the measurements were carried out. The air distribution of the system was measured. Furthermore temperature and electric power consumption have been measured over three years. The air distribution was reasonable, the temperature was moderate and the difference among the rooms was very small, and primary energy consumption was lower than the criterion of the energy standard in Japan. Thus the air-conditioning system was verified.

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 In recent years, global warming and the urban heat island phenomenon have become a serious problem not only in urban cities but also in local cities in Japan. One of the main causes is the change in land cover especially the loss of natural cover such as green spaces and water bodies and increase of artificial land cover such as buildings and asphalt coverage.
 In this study, we aimed to extract the degree of influence of the heat island phenomenon on the air temperature by analyzing the change in land cover and climate over the past 30 years across Japan. The study investigated the factors that influenced change in temperature at 288 weather observation points. Climate classification and geographical features analysis of all the stations was conducted. The results showed that the pacific side to the north from central Japan experienced a severe rise in temperature. Furthermore, the results showed that there was a moderate increase in temperature at points close to high altitude or latitude areas. In addition, we confirmed restraint in temperature at points close to the sea which were influenced by the effect of the water body.
 Investigation of the relationship between land cover and climate change showed that in the past 15 years there were many weather stations where there was decrease in natural land cover such as green spaces and an increase in artificial land cover. Moreover, in comparison to points with higher percentage of green cover, points with a higher percentage of artificial land cover showed a more rapid increase in air temperature.
  degree at which urban heat island phenomenon affects temperature was extracted from the yearly change in land cover of the selected regions. The results showed that in the period between 1985 to 2000, the average temperature gradient was 0.008°C per year. 14.3% of the temperature rise within the period was caused but the urban heat island phenomenon. In the period between 2000 to 2014, the average temperature gradient was 0.002°C per year. 22.2% of the temperature rise within the period was caused by the increase in urban heat phenomenon. Furthermore, as a secondary result, we found that after a certain percentage of green land cover is exceeded, the effect of restriction of temperature increase reaches its absolute peak.
 In order to understand the degree at which certain factors influence the air temperature increase, land cover condition, geographical features and wind patterns were stipulated as influencing factors. We quantified these factors and analyzed them using Hayashi's Quantification Method I. The analysis showed that latitude and land cover change had the greatest influence on the air temperature.
 From the above, this study extracted the degree at which the urban heat island phenomenon influences the temperature increase. In addition, we confirmed the influence of land cover change on the microclimate in an area. However, we could not analyze all the weather stations across Japan due to lack of satellite images in some points. Therefore, inclusion and analysis of these points and detailed investigation of the directional temperature around the weather stations are some of the points for further improvement in this study.

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 Energy consumption in houses depends on the lifestyle of the residents. It is important to grasp the trend of each household and to propose the energy-saving method to each home. We have been studying the estimation method of each usage of energy consumption. In the method, we use the only three measured data of principal electric power, gas and water consumption logged at a certain time interval. By processing the acquired data, we can grasp the energy consumption of hot water, heating, and other usage within a certain level of accuracy. We hope that the useful information for energy-saving behavior fit for every households will be provided.
 In this study, we measured the principal electricity, gas and water consumption data in large-scale apartment housings in the metropolitan area. Electricity is mainly used for lighting, electric appliances, heating (air-conditioner and electric heater), cooling (air-conditioner). Gas is used for hot water, floor heating, bathroom heating (the heat source of hot water, floor heating and bathroom heating is only one hot water boiler in each house) and cooking. Using electricity and gas for these purpose in the house is very popular in Japan. By using the data logged in every 10 minutes in 249 households and the data logged in every minute in 16 households, we studied the estimation method of electricity and gas consumption in each usage. As a result, the difference of estimated energy consumption between using the data logged in every 10 minutes and the data logged in every minute was quite small. Therefore, we confirmed that the data logged in every 10 minutes was useful to analyze the amount of gas and electricity consumption in each usage in recent apartment houses.
 By using this method, it was proved that the hot water and heating energy consumption in each household were drastically varied in winter. The amount of gas and water consumption for hot water varied every month according to outside air temperature and supplied water temperature. Nevertheless, the total amount of water consumption in each households did not fluctuate throughout the year. This tendency was similar to the precise evaluation by the data logged in every second in the past paper. Therefore, the method using the data logged in every 10 minutes was quite reliable. In the heating energy consumption, it was shown that the more residents live in the house, the total heating energy consumption and the ratio of gas usage became higher.

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 The purpose of this research is to predict the amount of the metal in home electrical appliances left at homes at time of tearing them down. We investigated the number and the processing method of home electrical appliance products left at homes at time of tearing them down by a questionnaire survey. From the results, we calculated that the number of home electrical appliances treated improperly. Furthermore, in order to predict the number of home electrical appliances were treated left at homes at time of tearing them down improperly in the future, we predicted houses that will be torn down in the future.
 From the questionnaire survey, we received from 414 house demolition companies, and from 366 industrial-waste disposal companies. According to the responses, from the home demolition companies, they said that the home electrical appliances that were left behind the most were air conditioners at 40 %. Next, compact appliances classified as bulky refuse (ex. heating installation, microwave oven and lighting system) was 33%. In addition, from the industrial-waste disposal companies, they said that the home electrical appliances that were left behind the most were compact appliances classified as bulky refuse was 44%. From the companies, they said that they knew the small size appliances (ex. camera, clock, and cellular phone) recycling law was about 60%. We guess that small size appliances are left behind because companies do not have the knowledge or know the right method for processing them.
 We predicted the number of housing stock and demolition houses. We predicted the number of home electrical appliances left at homes at time of tearing them down treated by improper processing. We predicted the integrated number of home electrical appliances left at homes at time of tearing them down treated by improper processing will be about 6 million from 2013 to 2053. We calculated this data based on the responses of the number of home electrical appliances left at homes at time of tearing them down and methods of treating home electrical appliances treated by improper processing in 2014. If most companies knew the small size appliances recycling laws, the number of small size appliances treated by improper processing would be reduced.

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