A model based on a two-layer zone model is proposed for the prediction of fire spread between combustible items in a compartment. Smoke layer temperature and height are calculated by the conservation of energy in the compartment. The effects of thermal feedback from flames, smoke layer and compartment surfaces are taken into account by radiation network. Calculation results of the heat release rate, smoke layer temperature, heat flux, and time to spread between combustible items were compared with those of model experiments carried out previously. As to the time to fire spread during the initial stage could be predicted fairly well. As the smoke layer temperature increases, this model seems to overestimate radiation feedback to fuel surfaces; this in turn estimate the shorter time to fire spread than that in the experiments.

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In Japan, there are many signs unrelated to safety and evacuation in buildings, because of insufficient regulation on advertisement placement. We comprehended the effects of setting conditions of signs on evacuee's ability to distinguish needed information.. We measured the amount of sign's information represented by configuration factor in the visual field with 1.0 m interval. In the results, the value of configuration factor of advertisements was greater than the others, and the one of evacuation guidance was extremely limited. We also examined the difference of results among interval levels and found out that the results with 5.0m interval could be treated almost the same as the one with 1.0m interval.

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The authors have developed a passive cooling wall (PCW) constructed of a porous ceramics. The ceramics has a capillary force to soak up water and allow its vertical surface to be wet to a level higher than 1 m when its lower end is placed in water. The present paper describes experiments to investigate the developed ceramics performance and cooling effects of a prototype PCW constructed of the pipe-shaped ceramics. The following findings were understood from experimental data monitored in a summer period. Wet vertical surfaces of the ceramic pipe reached a height of more than 1 m. Surface wet conditions can be maintained throughout successive sunny days in the summer. It was found that there is a slight difference in vertical surface temperatures of the ceramic pipe on a sunny summer day. The air passing through the PCW was cooled and its temperature can be reduced by several degrees in the summer daytime. It was also found that surface temperatures of the shaded ceramic pipe can be kept at a temperature nearly equal to the wet-bulb temperature of outdoor air.

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From the standpoint of creating a sustainable global environment, it is necessary to improve the building performance of school facilities. In this study, the actual conditions and problems of Eco-schools, which are specifically designed to optimize building performance considerations such as thermal insulation and sun protection, and which are funded by grants from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), are investigated through a nationwide questionnaire survey. The survey clarified that the thermal performances of numerous Eco-schools fail to meet expectations. For example, 16% of the respondent schools do not have thermal insulation installed and the thermal insulation performances of those buildings are lower than the 1999 energy standard for residential houses excluding schools in Zone I. Additionally, it was found that Eco-schools tend to consume more energy than older schools. Therefore, achieving higher levels of building performance is considered necessary for Eco-schools.

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When planning the thermal environment for an indoor area, it is critical to avoid uneven air flow distributions in the occupied zone and to ensure the conditioned air is uniformly circulated in the room. It is also essential to avoid generating cold drafts that may cause occupants to experience unpleasant chilliness. For these reasons, when air conditioning a large space it is common practice to employ a horizontal supply diffusing device that supplies air parallel to the ceiling from upper sections of the walls. In most horizontal supply diffusing devices, nozzle outlets with air long throw are commonly used. It is important to determine an appropriate supply velocity and an appropriate temperature difference between the nozzle temperature and the occupied zone temperature in order to appropriately control the thermal environment of rooms.
We have proposed a movable nozzle-type supply air outlets method in which the supply direction varies periodically as a means of controlling the terminal velocity in the occupied zone by increasing the diffusion area of the air flow without reducing the throw. A previous report compared the conventional outlet design guideline and the movable nozzle-type supply air outlets method by assuming the outlet is installed on the ceiling. It is confirmed that it is possible to constitute a comfortable occupied zone by adopting the movable nozzle-type supply air outlets to a large room by calculating the air diffusion performance index (ADPI). In the present report, the characteristics of the movable nozzle-type supply air outlets method are analyzed by assuming that the nozzle outlet is on the wall and by using an unsteady simulation based on a CFD simulation. The ADPI is used in the thermal environmental evaluation of the occupied zone in a similar manner as the previous report. However, in this present report, the effect of drafts in the occupied zone is additionally evaluated using the draft rating (DR) that calculates the effect of drafts in the occupied zone based on the air flow velocity and the occupied zone temperature.

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The impact of the pollution caused by human bioeffluents on the occupants' perceived air quality was studied in two different thermal conditions, i.e., warm condition (28°C), and neutral condition (25°C) air-conditioned by heat pump. Fifty subjects occupied a room for 75 minutes in the above conditions. The concentrations of VOCs were also measured for identifying possible VOCs emitted from human bioeffluents. VOCs presented in the room air of warm condition showed the presence of various types of compounds including organic fatty acids, alkane, aromatic compounds, and aldehydes. Besides above VOCs, which might be emitted from human bioeffluents, were not derected in the air-conditioned air and background. The occupants evaluated thermal condition, air freshness, feeling of sleepiness, easiness to concentrate though questionnaire. Occupants in the condition of 28°C felt malodor such as body odor and felt discomfort to IAQ.

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In order to make clear the relationship the chemical substances concentration and symptom of sick house syndrome, an investigation of 62 houses in Japan has been done for 9 years. The results showed that the indoor air of many sick houses was polluted with high carbonyl compounds and Volatile Organic Compounds (VOC) concentrations exceeded the criterions of Japan Standard. In addition, high concentration was found not only in the houses which were just built or renovated, but also in the houses with well-air-tightened and low air change rate.

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It is important to manage the residual disinfectant concentration as a countermeasure against Legionella for circulation bath. Based on the experimental data, this report examines that the differences of measuring results by absorption spectrometry which are used for determination of chlorine dioxide concentration. As a result, the simple DPD measuring device could be measured in the high precision like a spectrophotometer which went at a laboratory. Bath water however, the simple DPD measuring device could be measured in the high precision like the tap water. And it found that it was possible to use as a chlorine dioxide concentration measuring method which uses the simple DPD measuring device on fields. When measuring chlorine dioxide concentration, the influence of free residual chlorine can restrain a glycine by adding it.

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This study intends to propose a testing method for examining the influence of combined drainage in the house drain on the drainage performance of the stack drainage system which is used for housing complexes. The study also intends to propose a drainage performance prediction technique using the testing method, and subsequently discusses the effectiveness of the testing method and the prediction technique. Subsequent to the previous paper, this paper aims to clarify, using the drainage system with special fittings, the following three points: (1) the aeration property of components of the model, which was proposed in the previous paper for predicting the pressure in the house drain when combined drainage occurs, and evaluate the adaptability of the model, (2) using the model, the prediction of the drainage performance of the house drain which is connected to the stack drainage system and compare acquired values to the SHASE-S206 values, (3) the discussion on the vertical height of the horizontal fixture drain branch against combine drainage, i.e. the horizontal fixture drain branch installable at the lowest floor from the house drain. Based on the above points, this paper also looks at the characteristics of combined drainage in the house drain, which are different when the house drain is on the drainage system with special fittings and when it is on the drainage system with JIS-DT fittings.

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The purpose of this research is to develop "The Optimization Tool" that achieves the optimization of the air-conditioning system operation in general building air-conditioning systems. The influence of errors in the load prediction, which is the biggest problem in realizing the optimization, is examined in this report. It is shown that there is a case where the operation deteriorates due to the optimization when the margin of error is large. Thus, an optimization technique that takes into account errors in the load forecasting is suggested, and the technique is proved to be a robust procedure which stably selects appropriate set values.

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This study aims to found the basic data for promoting energy conservation policies by assessing the energy consumption in common space of apartment block. We investigated the actual electricity consumption in common use space of apartment houses. The data of electricity usage in common use space was collected from 1,345 apartment blocks (623,022 houses). We classified the apartment blocks by 1) year when administration had started, 2) number of floors, 3) number of houses, 4) water supply method and 5) number of elevators, in order to analyze the influences of those attributes on the electricity consumption. As a result, it became clear that the specific energy consumption of the apartment block differs significantly in the range from 42 kWh/year/house to 2,272 kWh/year/house, depending upon the abovementioned attributes.

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This paper presents simple and practical measuring system in order to determine the solar shading and heat transfer performance of advanced windows in actual conditions and verifies measurement accuracy of this system in practical use.
The presented system enables to measure directly heat gain from the window without assumption of heat transfer coefficient, and verified measurement accuracy by the examination using full-sized window mock-up and heat generator. In addition, existing calculation model for estimating annual heat load is verified in validity by comparison of long term actual measurement.

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This paper describes an energy demand model of the commercial sector of Osaka city. We investigated the distribution of building stock in terms of building size and the utilization of energy saving measures. The modelling methodology is designed to take into account the distribution of building stock and energy saving measures as well as building attributes with a significant influence on the energy consumption. By using the model, we estimated the potential reduction of CO₂ emission that can be gained by disseminating energy saving measures and energy efficient lighting devices and heat source machines in the sector.

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In recent years, high-albedo materials and products have been utilized for urban building roofs and roads to lower their surface temperatures. These high-albedo materials and products include those with spectral selectivity. Accordingly, a scale model experiment and a numerical simulation were conducted to investigate the spectral dependency and characteristics of the urban albedo. The experimental results suggest that the spectral albedo is high in the near-infrared region especially in hours with low solar altitudes. The distribution of the spectral albedo relative to the albedo over the entire spectrum agreed well between the experimental and numerical investigations. The effects of the spectral selectivity of urban materials on the urban albedo are discussed using the results from the numerical simulation.

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In building sector, improving energy efficiency, reducing energy consumption and organizing energy in buildings, or switching to low-carbon fuels including a higher share of renewable energy are studied in many researches. Renewable and low-carbon energy can be supplied to buildings or generated on-site by distributed generation technologies. In distributed generation system among buildings, there is enormous amount of combinations between energy demand and energy supply. So it is difficult for stakeholders to make a quantitative evaluation about which energy system is the best, what way to operate equipment is the best, in order to minimize environmental impact. The authors have developed the optimal design method for building energy systems using “Genetic Algorithm (GA)” which could deal with nonlinear optimization problems. In this study, the effect of GA parameters on the prediction accuracy is estimated and this method is applied for distributed energy system using cogeneration system. The result shows that the cogeneration system has the potential to reduce energy consumption to some extent.

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The number of schools, where air conditioners for cooling are equipped, has been rapidly increasing in Tokyo. Although most home has air conditioner in Tokyo, Pupils do not get used to school life exposed to air conditioned space in public elementary schools. The purpose of this study is to investigate the change of pupils behavior and corresponding indoor environmental change after installing cooling system into classrooms. Air temperature, relative humidity and CO₂ concentration were measured during summer season in twelve classrooms in an elementary school before installing cooling system and after installing. The investigated public elementary school is located in downtown Tokyo and has twelve classes, i.e., each grade has two classes. The questionnaire survey was conducted for investigating pupils perception and learning performance after installing air conditioner. The absenteeism survey was also conducted for health effect of air conditioned classroom.

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[in Japanese]

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Air quality, thermal environment, and several environmental controls were investigated in elementary school classrooms equipped with cooling systems in mild climate areas. Pupils' thermal evaluations and preferred temperature evaluations were obtained from a questionnaire. There were variations in control conditions of cooling systems at the beginning of summer while cooling systems were almost always operated in midsummer. There were classroom and seasonal variations in opened and closed conditions of windows and doors while cooling systems were operating. Outside windows were completely closed in many classrooms while cooling systems were operating in midsummer. When windows and doors were closed while cooling and heating systems were operating, there were air quality problems such as increase in indoor CO₂ concentration. Excessive increase in indoor CO₂ concentration could be avoided by opening windows and doors on corridor side. The neutral temperatures based on pupils' thermal evaluations changed seasonally and declined to outside temperatures compared with neutral temperatures of adaptive model in case less than 20°C.

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In almost all the Japanese versions of Mies's inaugural address at AIT the German word, ‘Persönlichkeit,’ was translated as the Japanese word, ‘Kosei,’ and in Japan they have circulated Mies's respect for ‘Kosei’ in architectural education. The meaning of ‘Kosei’ contradicts not only the meaning of the other sentences, but also his other discourses. Investigation into the process of translation from German through English to Japanese shows that there were some subtle differences between them. They derived the unsuitable equivalent, ‘Kosei,’ distinctive character of a person for ‘Persönlichkeit.’ The more appropriate equivalent is ‘Jinkaku,’ the condition of being a person.

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