Tempered fire resistance glass is designed to be able to tolerate thermal stress on fire by giving the surface compression stress that is higher than general tempered glass. However the surface compression stress is able to be measured by optical method along Japanese Industrial Standard, but edge strength is not able to be checked without breaking glass panes. On setting glass strength, many glass panes are broken and the glass breaking stress obtained by statistically processing becomes allowable glass stress. In the previous report, it was obtained as basic knowledge that there was a strong correlation between temperature difference ΔT and surface compression stress. However, even if glass had high surface compression stress, if the edge strength of the glass is much lower, it is quite possible that the tempered fire resistance glass is broken in an early stage of fire. Therefore, tempered fire resistance glass has to be evaluated as the total strength about both the surface compression stress and glass edge strength. On this study, the glass edge strength was checked by glass breakage four-point bending tests, tempered fire resistance glass in the same production lot was used in fire tests. The surface compression stress was measured the glass that is evaluated by fire tests. To grasp the correlation between temperature difference and the total glass strength of tempered fire resistance glass, the temperature data of glass was obtained by fire tests.
 The four-point bending test condition is shown below.
 ·Glass size is W1,000mm×H100mm, glass thickness is 3mm～12mm , and the number of glass panes is 50 sheets.
 ·The glass was put on the supported point of the 900mm span, and was loaded from the upper end of glass on loading point of the 300mm span as four-point bending test method.
 The fire test condition is shown below.
 ·Fire tests were performed for Single glass panes and Low-E Insulated Glass Units.
 ·Concerning Low-E -IGU, tempered fire resistance glass was located on fire side(Figure7, 8).
 ·Fire tests were performed along the ISO834 Heat Curve for each specimen.
 ·The temperature of the glass was measured by thermo couples with a data logger.(Figure9).

 Findings are as follows.
 1) Glass edge strength was checked by glass breakage four-point bending tests. Figure 2 shows that the total strength of tempered fire resistance glass could be expressed as surface compression stress and edge strength. On this study, the edge strength was treated as lower-limit value of the lognormal distribution 3σ_n-1.
 2) Figure10, 13, Table10, 11 show that the upper peak of temperature difference arrives at 400K degree for Low-E IGU, at 300K degree for Single glass without depending on the glass thickness. That is to say, the strength of tempered fire resistance glass for Low-E-IGU needs to be much stronger than Single glass.
 3) Figure15, 16 show that on this fire tests, fire tempered glass or Low-E glass was broken by touching each other on 10mm and 12mm thickness of tempered fire resistance glass. That is the reason why the glass that has the thickness is easy to increase temperature difference of front and back sides, and the touch is caused before glass temperature is reached at softened temperature.
 4) The lowest total strength for tempered fire resistance glass not to be broken could be evaluated by ΔT without depending on the glass thickness from a number of fire tests. (Formula 4: σ₀>0.6178·ΔT_max+5.161) The thermal stress of the glass was expressed in consideration of a parameter to affect the difference of temperature (Formula 3: σ₌0.608·K·ΔT)

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 In order to reduce big damage by conflagration caused by devastating earthquake, we must give high priority on fireproofing high density areas of wooden houses in big cities. Joint rebuilding in these areas is expected as the most effective measure of disaster control of this kind.
 However, landowners tend to maintain the status quo and consensus making of rebuilding do not go forward easily, while they understand the utility of joint rebuilding to some extent. As the reason for this, road conditions of building lots in those areas are not sufficient compared the request by Japanese Building Code. In addition, transaction costs are felt as big burden.
 The prisoner's dilemma in game theory can explain this kind of situation. We analyzed this situation with the prisoner's dilemma in game theory, and clarified the obstacles and externalities concerning joint rebuilding. We verify the validity of the prisoner's dilemma model with effects of policies predicted by the model and several joint rebuilding examples. Furthermore, based on this analysis, we examined effective and fair policies to use mediators, embedding commitment devices with fair building restrictions, and/or reduce transaction costs.

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 The present study aims to demonstrate the degradation of intelligibility of Japanese words at higher than normal speech levels in reverberant fields. The reason why the degradation of intelligibility due to increased speech level have not yet observed clearly seemed to be that only high-familiarity-word-lists were used in almost every study on speech intelligibility in Japan. The score of intelligibility tests with high-familiarity-word-lists keeps almost 100 % till the hearing condition degrade to some extent, so the degradation of hearing condition due to increased speech level rarely reflect on intelligibility score. On the contrary, the intelligibility test with low-familiarity-word-lists responds sensitively to a small difference of hearing condition. Therefore the present study uses these two lists and demonstrates the degradation of intelligibility due to increase of speech level.
 Reverberation is added to the test words by reverberation unit (YAMAHA Srev1). Reverberation times of test fields are set 0.8, 1.4, 2.0 and 3.0 s and STI values are 0.791, 0.672, 0.633 and 0.578 respectively. Speech levels are set at 6 steps of 5 dB interval from 70 to 95 dB and adjusted at the position to be the center of the head of the subjects. Subjects are 10 young persons (age of 20-25) and 29 aged persons (age of 65-82). Hearing loss consistent with age was observed in aged group. Intelligibility tests were conducted in an anechoic room with one loudspeaker radiating reverberation added test words.
 The significant degradation of intelligibility due to speech level increase at higher than normal speech levels was not observed by intelligibility tests with high-familiarity-word-lists. However the degradation is clearly observed by tests with low-familiarity-word-lists. The degradation of young group starts at speech level of 70 dB and of aged group 80 dB. The degree of degradation of intelligibility per speech level is -0.80 RAU/dB for young group and -1.20 RAU/dB for aged group, and no significant difference is observed as to reverberation time. Here, RAU is the unit transformed from intelligibility score, rationalized arcsine unit.

 SII (Speech intelligibility index) is the only physical index that can evaluate the effect of absolute speech levels. So the correspondence between SII and the result of the intelligibility tests was examined. The figures which show the word intelligibility as a function of SII (figure 12–15) demonstrate that SII can be an index rating the effect of reverberation and speech level all together for each subject group. Though SII include healing level as a factor and must be an index which can rate intelligibility of different hearing level group all together, the figures indicate disagreement.
 The disagreement between different hearing groups seems to occur from ‘band audibility function’ in calculation of SII. So a correction of ‘shift factor’ was introduced to calculation of ‘band audibility function’, and the optimum value of ‘shift factor’ was searched. The optimum values of correction are 2.5 dB for the whole aged group, 1.5 dB for the aged group of hearing level lesser than 25 dB, and 4.0 dB for the aged group of hearing level greater than 25 dB. It is shown that the corrected SII calculated with corrected ‘shift factor’ can evaluate the effect of reverberation, speech level and hearing level all together (figure 16–19).

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 There has been a significant increase in foreign visitors to Japan in the past few years. In 2010, there were 8.6 million foreign visitors, which more than doubled in 2015 to 19.7 million. Consequently, the Japanese Government increased their expectation to 40 million visitors in 2020 when the Tokyo Olympic Games are to be held. Therefore, the need to establish multilingual charts and signs at railway stations has become increasingly urgent. Signs and charts at many Japanese stations are only in Japanese or in Japanese and English. However, because of space restrictions, it is often difficult to find a place for these multilingual charts or signs. Installing fare charts near ticket vending machines also has similar problems. Therefore, determining the optimum text size and luminance for such charts is necessary.
 The objectives of this paper are to assess the influence of viewing distance, character size, and luminance on the visibility of the station name on installed fare charts and to propose improvements to the fare charts to ensure that they are easily read by visitors.
 First, a measurement investigation was carried out on the currently installed fare charts and their installation environments, after which an evaluation experiment was conducted on the visibility of the currently installed fare charts. The following results were obtained.
 For the ticket vending machine illumination, no participants felt that it was too dark when the illumination exceeded 400 lx; however, at 200–300 lx, some participants felt that it was a little dark, and at 50 lx, all participants felt it was too dark. Therefore, it is recommended that illumination should be 200 lx at a minimum with 400 lx being the ideal illumination.
 The elevation angle, viewing distance, text size, and chart luminance influenced fare chart visibility. The elevation angle affected how close a customer can make an approach to read the fare chart and it was found that the elevation angle was ideal at less than 37°, with indistinctness experienced at around 45°.
 The viewing distance, text size, and chart luminance also influenced fare chart visibility. Using multiple regression analyses, an estimated formula with high fitness (the adjusted R-square was 0.80) was determined. It was found that if the text size is 15 mm, when the luminance is doubled, the viewing distance is about 20 cm.
 To determine what improvements need to be made, the visible area of the fare chart at E gate of A-railway was taken as an example. If the fare charts were lowered by 25 cm and the luminance increased to 200 cd/m2, the near point of the visible area would be 77 cm and the far point would be 422 cm, increasing the visible area to 345 cm, an increase of 35%. And then, if the installation height were lowered by 25 cm and the luminance increased in all areas to at least 200 cd/m2, the fare chart size could be reduced to 80% of its present size to ensure current visibility. A reduction of 80% means that the fare chart installation area would be 64% of its current size.

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 Along with the development of lighting engineering during the high-growth period of the Japanese economy, the idea of "the brighter, the better" has become the paradigm. Darkness has been an essential part of Japanese architecture, to reveal its soft lighting distribution and to show expressions of texture being used. Several studies on darkness have been carried out to show the evaluation items, and shown that pleasant darkness depends on behaviors and lighting methods. Yet, these studies do not clarify the quantitative lighting environment range of pleasant darkness. Therefore, this research aims to show the pleasant darkness range depending on the lighting method and behavior of the room. Most standards use illuminance; yet, most designers agree that illuminance is not enough for designing, and researchers point out that luminance is more related to brightness of space. Therefore, within this research, lighting environment is defined not only by illuminance levels, but also with luminance distributions and several indices derived from them.
 The preliminary survey was conducted to define the target usage for the experiment. From the result of brain storming of "dark space", and pleasantness evaluation of it, a restaurant was set to be the target of this experiment. As a result of further literature survey of architectural magazines, three most popular lighting methods were selected to be the experimental setting. 1. Using spot light to lighten the table top, 2. uniformal light with down light and 3. spot light for table and indirect light for lightening walls.
 The first experiment was undertaken to select the most suitable experimental method and to verify the range of darkness. Experimental apparatuses were set as follows: square room with the white interior, a square table with food models, one spot light lightening the table top, and each participant eating with a mannequin as an accompanying person. 20 subjects were asked about the lighting environment using the adjustment method and the constant method. As a result, the existence of pleasant and dark lighting environments was shown using both experimental methods. The pleasant darkness range derived from constant method were between 120 to 151 lx and that of adjustment method were between 133 to 159 lx. For shortening experimental time and getting the precise threshold value, the experimental method of the second experiment was set to be the adjustment method.
 The second experimental was performed to see the relationship between the pleasant darkness and the lighting method and assumed behaviors. Three lighting methods and four behaviors (eating, drinking, chatting and relaxing) were set, and 20 subjects were asked to adjust until they reached the threshold value of darkness with ascending and descending series. The same procedure was taken for the pleasantness value. Using the logistic analysis, the pleasant darkness range were derived. ANOVA showed that the darkness threshold value and the pleasantness threshold value differed, and that these results were valid. The average luminance range was 5 ~ 17 cd/m². According to the main visual target, the most-fit lighting environmental index differs.
 Experimental values were compared with the standards. The experimental results shows that subjects felt pleasant even if the average illuminance level is lower than the standard level. On the other hand, AIJES suggests the usage of average luminance of the interior surfaces. The experimental results showed that pleasant luminance level differs by the lighting method being used. Further investigations using different interior materials and different levels of brightness is needed.

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 Japan establishes the goals to realize ZEBs (net zero energy building) in average newly constructed public and private buildings by 2030. The primary energy consumption of the illumination in the office building accounts for around 20% of the whole building. Therefore, thorough saving energy is demanded for illumination to achieve ZEB.
 The effective method for the saving energy of illumination is the use of day light. The natural light of the workplace in office building is generally adopted through a side window. Venetian blinds are installed in the window for solar shading. In the automatic blind control system installed at the large scale building, slats of blind are uniformly controlled by illuminance censor fixed on the top of the building. This is not able to detect direct sunlight and the light from adjacency building at the side window.
 We devised technique to detect not only the direct sunlight but also the dazzling borrowed light from adjacency building based on a luminance image provided with a CCD camera for the purpose of the development of the higher precise judgment of solar shading. We built the system which could perform shading immediately at the time of the detection and introduced it into the actual work office.
 As a result of proof experiment, the following knowledge was provided in conclusion.

 1) A method to measure high range of luminance including direct sun light and the borrowed light by a fisheye lens and the CCD camera which attached two kinds of filters which varied in the spectral transmittance was showed.
 2) Using luminance contrast (C value) and the logarithm luminance mean (A value) to be provided by N filter and the averaging filter developed by Nakamura, detect direct rays of the sun and borrowed light can be identified in luminance image.
 3) The threshold of C value: 0.4 and A value: 4.5 that can detect direct rays of the sun and borrowed light using the luminance image measured at single shutter speed of 1/200 second by the CCD camera are identified for speedup of the control.
 4) The evaluation method proposed in this study applied to blind control system in actual workplace could detect direct sun light and borrowed light of neighboring buildings with high precision and was able to confirm the usefulness and effectiveness.
 5) The possibility that could contribute to increase of the day lighting and view-related improvement by controlling every window is showed
 6) The result of this study showed the possibility that could help it toward the spread of blind control systems with higher precision.

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 Assessment of the energy saving performance of high performance glass, selective coatings, and photovoltaic power generation systems in buildings requires data, the annual spectral solar irradiance under all weather conditions. Existing annual hourly weather data include the amount of solar irradiation measured with pyranometers, but there is a lack of spectral solar irradiance data. Thus, for the results to be meaningful, a model of spectral global solar irradiance and a model of spectral direct or spectral diffuse solar irradiance are necessary to supplement the existing hourly weather data.
 In this paper, we develop a simple regression formula that estimates spectral diffuse solar irradiance incident on a horizontal surface from four weather parameters, such as diffuse solar irradiation, global solar irradiation, air temperature, and humidity.
 Using grating spectroradiometers (MS-710 and MS-712) with rotating shadow blade (PRB-100) to record the irradiance between 350 and 1700 nm, we measured the spectral global solar irradiance and the spectral diffuse solar irradiance under a variety of weather conditions for two years, from 2010 to 2011. Simultaneously, we also used a pyranometer (MS-802), conforming to the ISO 9060 Secondary Standard, to measure the amount of diffuse solar irradiation between 305 and 2800 nm. These measurements were conducted at Kagoshima city, Japan.
 Using the measurements from 2010, we found a high degree of correlation between the spectral diffuse solar irradiance and the amount of diffuse solar irradiation.
 We then created a regression formula that estimates spectral diffuse solar irradiance from 350 to 1700 nm at 5 nm intervals. In this regression formula, the amount of diffuse solar irradiation is used as an independent variable. We also found that the coefficients of this regression formula vary depending on the wavelength of the solar irradiance, clearness index, air mass, and precipitable water in the atmosphere. Using these variables we divided the measurements into 36 datasets, and using the least squares method we determined the coefficients of this formula on 36 weather conditions. We then used Equation (5) with these derived coefficients as the equation to estimate spectral diffuse solar irradiance.
 Using Equation (5), we calculated the all-weather spectral diffuse solar irradiance during 2011 and compared it with the measured values. The root mean square error for the estimated spectral diffuse solar irradiance with respect to the measured values was found to be 0.1～30.7 [W/m²/μm] at 350～1700 nm.

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 In this research, we report the development of a new model of heat pump used for annual energy simulation of building. The main conditions that affect the energy consumption of the heat pump are the flow rate, temperature of the chilling and cooling water and partial load rate. Therefore, many of the previous characteristic models also calculate energy consumption with using these elements. The temperature related to the condensing or evaporating temperature is not the inlet temperature but the outlet temperature of the heating medium to be sent to the heat pump, but most of the previous models use the inlet temperature to avoid iterative calculation. In recent years, a new heat pump machines has been provided on the market that achieves high efficiency by lowering the compression ratio by utilizing a low condensing temperature like an inverter centrifugal chiller. The heat pump system using geothermal is also increasing. In these systems, it is impossible to find the optimum operating point by predicting the efficiency of a single heat pump machine. It is necessary to predict the influence of simultaneous change of the flow rate and temperature of cooling water on heat pump.
 The feature of the model proposed in this research is that the characteristic expression used in the model makes it possible to calculate the outlet temperature without performing iterative calculation. Chapter 2 describes the problem of characteristic expression of existing program. Chapter 3 explains how to formulate characteristic equation in this model. Chapter 4 reports characteristic coefficients of geothermal heat pump model and the case study results.

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 Residential photovoltaic (PV) systems are becoming increasingly popular. However, the satisfaction level of PV users has been scarcely studied, despite the fact that user satisfaction affects the future prospects of PV systems. Specifically, no research has been conducted on the influence of performance of PV systems on user awareness of these systems.
 In this context, we undertook a survey to look at the relationship between PV system user awareness and the performance of PV systems. The survey was conducted between December 2015 and January 2016 and included residents living in detached houses with PV systems. We received 571 valid responses, including 283 responses for annual power consumption and 183 responses for monthly power consumption. Followings are the main results of this study:
 · Users who recently installed PV systems tend to choose these systems for reducing their electricity bill and/or selling electricity. They were less likely to choose these systems for reasons of energy conservation/environmental protection and/or the enjoyment of generating electricity at home.
 · The overall user satisfaction rate is 90%, with 52% who indicated they were “satisfied” and 39% who indicated they were “relatively satisfied.” This demonstrates that most users have positive attitude towards PV systems.
 · Seventy percent of the following user groups indicated they are “satisfied” with PV systems: users who rated themselves as “very conscious” about saving power in everyday life; users who rated themselves as “very conscious” about choosing environment-friendly products and services; users who consider PV panels to “add to the beauty of their houses;” and users who have used a PV system's self-sustained operation more than twice during a power failure.
 · Users with a high overall satisfaction rate tend to be interested in increasing PV system capacity and driving electric or plug-in hybrid vehicles. We also found a statistically significant relationship between user satisfaction and using a personal electric or hybrid vehicle as a power source for a PV system. Furthermore, users with a high satisfaction rate have a greater tendency to recommend PV systems to others.
 · The average capacity of a PV system is 4.8 kilowatts (kW). The mode of photovoltaic power production is between 1,200 and 1,300 kWh annually. The PV system performance ratio, which represents power generation performance, is between 0.80 and 0.85 (n=283).
 · The percentage of generated power being used at home annually is 27% in the houses with electric water heaters, and 26% in other houses (n=99).
 · The ratio of power generation to electricity consumption is 0.68 in houses with electric water heaters and 1.15 in other houses. Seventy percent of other houses (n=69) and 22% of houses with electric water heaters (n=40) generate more power than they consume. At least 10% of houses with electric water heaters have achieved having a Net Zero Energy House (ZEH).
 · When the PV system performance ratio is higher, user satisfaction with power generation is also significantly higher. We also found that when the PV system performance ratio is less than 0.75, negative reviews outnumber positive ones among users who installed PV systems for reducing their electricity bill and/or selling electricity.

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 In urban areas where population and city functions are aggregated, there are calls for the construction of business continuity districts, in which energy supply is secured in times of disaster. A decentralized and self-reliant community-level energy network is expected to contribute to improving resilience and regional vitalization, as well as to reducing carbon emissions. However, the initial investment is high and the stakeholders involved are diverse, creating potential obstacles to the introduction of such an energy network because the necessary measures are of larger scale than a simple construction project. Prior studies have shown the need for accurate recognition of non-energy benefits (NEBs) in addition to energy benefits such as energy cost savings. Moreover, evaluation methods for various co-benefits have been proposed. Yet, NEBs accrued through risk reduction have not been evaluated with respect to temporal changes in business and daily life activities associated with lifeline utilities such as electricity, water, and gas.
 In this study, we conducted a questionnaire survey of city residents and non-manufacturing workers. Using the data from the questionnaire, we developed an evaluation method for improvements in resilience. In addition, we verified the effect of improving resilience through a case study of a real urban district and a housing complex district.
 The results of this research are summarized below.
 (1) Proposal of an evaluation method for resilience in the business sector
 In the questionnaire survey, we asked non-manufacturing workers about the effect on business activities of lifeline stoppages (electricity, water, and gas) and derived a “Resiliency Factor” according to the type of business. Then, we proposed a method for resilience improvements based on Resiliency Factor and a recovery curve for business activity according to the lifeline stoppage time, and we plotted a recovery curve for business activity according to the lifeline stoppage time. In addition, we expressed the resilience improvement in the business sector in monetary terms.
 (2) Proposal of an evaluation method for resilience in the housing sector
 In the questionnaire survey, we asked residents about the losses incurred as a result of electric power failure. Then, we derived a basic unit of loss due to electric power failure according to stoppage time. This basic unit was then used in an estimation model considering housing type and location to assess resilience improvements in the housing sector in monetary terms.
 (3) Case study
 We performed a case study of the effect on resilience of introducing a community energy network under the assumption of a large-scale earthquake. In the evaluation, the Tamachi Station district was taken as an example of urban areas and the Hamamidaira housing complex district was taken as an example of areas around existing housing complexes We found that by introduction of the community energy system, the Tamachi Station district would accrue NEBs of 140 million yen per year and the Hamamidaira housing complex district would accrue NEBs of 5.11 million yen per year.

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 We have proposed the below two calculation models efficient for estimating indoor radiation dose; 1) a calculation method of transport of photons released from radioactive materials that were deposited on solid surface such as ground surface or building walls, 2) a model using a single-layer wall that represented and was equivalent to a multiple layered wall consisted of different building materials. RADAR-γcode which has been developed on a basis of a series of this study was applied to estimate indoor radiation dose (rate) for Meckbach's prefabricated house and detached house proposed by IBEC.

 Indoor radiation doses calculated for Meckbach's wooden prefabricated house were 10 ~ 20 % higher than in Meckbach's paper. The discrepancies could be attributed to values of linear absorption coefficients of building construction materials and ways of dealing with the buildup effects.

 As for IBEC detached house, three types of building structures have been considered; concrete, light-weighted concrete (ALC) and wooden house. The indoor radiation dose rates estimated by this study were in good agreement with calculation results of Furuta et al. when we compared with houses of same type of structures in almost the same position. The indoor radiation dose rate tends to decrease as density of building construction materials used increases. In a case where Cs-137 has infiltrated into soil, the radiation dose rate in second floor tends to be lower than the rate in first floor for a concrete house, but tendency turns out to be opposite for a wooden house.
 In this study, the exposure buildup factor in concrete material was used for all materials because the exposure buildup factors are not so much different by materials since the mean free paths of photons occurring in detached houses are thought to be less than three or so.

 Although half-life of Cs-134 is about two years, which is much shorter than 30 years of Cs-137, the radiation dose per a decay is estimated by a factor of 2.75 of Cs-137. Considering these facts, the radiation dose (rate) from radioactive cesium can be estimated to be k - fold of the radiation dose of Cs-137. n is the number of years since the nuclear accident occurred (2011.3).
 k = 1 + 2.75 × 0.5^0.451n

 A package of the methods for easier prediction that have been proposed in a series of this study can be utilized to estimate radiation dose (rate) in houses built in areas containing radioactive materials on ground or in soil. Adequate buildup factors must be chosen when it is used for radiation protection facilities.

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