In Japan, “open-plan” type classroom is becoming popular in elementary schools. Although this planning has various merits for educational activities, sound propagation between adjacent classrooms tends to be a serious acoustical problem. In this study,therefore, the sound propagation between closely located two classrooms connected by an open-space was investigated by numerical simulation using FDTD method. In the simulation, two classrooms and the open-space connecting them were modeled and the configuration of the rooms and sound absorption treatment on the room boundaries were examined. As a result, it has been found that sound absorption treatment on the ceiling and architectural/acoustic treatment for the wall of the open-space which makes mirror-reflection are effective to mitigate the sound propagation between the classrooms.

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The construction of precision facilities that must be protected against vibrations caused by main roads and railways has been in great demand. In order to satisfy the requirement of performance of these facilities, it is necessary to control the vibrations within the allowable limit being strict for precision instruments in buildings. This implies necessity for development of 3-dimensional dynamic soil-structure analysis that makes it possible to accurately predict the vibrations transmitting from sources to structures via soils, and to apply the most suitable measures for reduction of vibrations. Therefore, we have developed the analysis technique that combines 3-D FEM with thin layer method to predict the ground vibrations produced by traffics, machines and construction operations. Hence, 3-D FEM and thin layer models represent near-field including structures and far-field, respectively. The shaker test in the ground and the rapid load test were simulated, and the effectiveness of this analysys method was confirmed.

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For designing a comfortable visual environment, it is necessary to estimate adaptation luminance of the whole visual field with complicated luminance distribution. It is thought that such adaptation luminance is estimated by considering the summation of the adaptation luminance increase that is the effective luminance brought by a partial luminance of visual fields. For estimating the adaptation luminance, the additibity of adaptation luminance increase should be confirmed to the whole visual field.
Under the various patterns of high luminance surfaces arrangement covering the whole visual field, the luminance difference threshold is determined to each subject for getting adaptation luminance. From the result of such subjective experiments, the additivity of adaptation luminance increase was confirmed in this paper.

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Openable windows of multiple dwelling houses or office buildings are often put on the single-sided wall because of restriction due to architectural planning. Conventional prediction method of airflow rate based on the differential pressure coefficient works on the assumption that openable windows exist on the both, windward and leeward sides of the room. This method is not useful for the room with single-sided opening. The prediction method of air flow rate of single-sided room beneficial to design process is not sufficiently prepared.
In this study, the characteristics of wind induced ventilation with single-sided opening are analyzed with wind tunnel experiment, in which wind velocity profile of the approach flow is created as well as wind velocity profile around a building in build-up area. The normalized airflow rate 'k' is obtained from the wind tunnel experiment for simple prediction of airflow rate of single-sided room. The simple prediction method is mainly based on the normalized airflow rate 'k' and assumed wind velocity around a building, which is decided by CFD simulation or measurement.

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This study aims at the development of the coupled simulation of building energy simulation and computational fluid dynamics (CFD). We proposed the indexes called CRI (Contribution Ratio of Indoor climate), which represents how each heat source (sink) in a room contributes to form the local air temperature in a specific flow field, and how to predict room air temperature at arbitrary points by CRI. In this paper, we propose a new approach to integrate the information of the spatial distribution into the energy simulation program by expressing the air temperature as a function of CRI and the potential of each heat source. This integration method enables the energy simulation to consider the spatial distribution.

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Tracer gases and their monitoring method were studied to measure ventilation rates using the tracer-gas-decay method. Five kinds of gases:sulfur hexafluoride, nitrous oxide, carbon monoxide, carbon dioxide and isobutene were compared from the viewpoints of global warming potential,toxicity, performance and cost. In addition, Photo Ionization Detector was used to compare Photo Acoustic Sensor and Semiconductor-type monitor in some new buildings. The system using isobutene and a photo ionization monitor for measurement was proposed, and the procedure of the system and performance conditions in the fields were studied.

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Chemical Sensitivity (CS) is a disorder in which people report negative symptoms in response to chemical exposure. To examine and treat CS patients, special facilities are needed in which chemical contaminants are minimized. The purpose of this study is to establish methods of reducing contaminant concentrations in new diagnosis and treatment facilities for CS. We developed a special activated carbon (SAC) for the chemical filters, and tested their performance. It was confirmed that SAC was superior to commercial activated carbon for reducing chemicals and particle emissions. We also determined suitable construction materials for the facilities by chemical emission tests, and developed a new bond without polymers for the facilities.

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The aim of this study is to verify the usefulness of thermal storage cooling system for external insulated detached houses built from reinforced concrete. After actual survey of model houses built in Saitama prefecture in the hottest summer season, COP of heat pump (primary side) including that of circulation pump (secondary side) was concretely estimated, and also the performance of this system, such as a floor cooling system by using water as the thermal medium, was evaluated. At once, the evaluation of thermal comfort and humidity management when this system was introduced was practiced, and also the possibility and problems of a floor cooling for highly insulated buildings in the future were revealed.

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We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used sensible thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. It is revealed by experimental studies that thermal behavior of the room is greatly influenced by the heat capacity of the thermal storage. We constructed a computer simulation program of this heating system and showed the ratio of the stored heat for generated heat by the heat pump with the volume of the thermal storage materials. We showed the way to determine the volume of the thermal storage materials and the capacity of the heat pump.

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We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used latent thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. We showed equations to determine the air volumes of the heat pump and the ventilator, and equations to determine the phase transition temperature and the amount of the latent thermal storage materials to keep the room setting temperature. We constructed a computer simulation program of this heating system and confirmed the validity of these equations.

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This paper shows a method of calculating steady-state energy consumption of hot water heating systems by using parameters obtainable in design phase such as plan, characteristics of the boiler, piping, floor and so on. Calculation models of three parts of floor panel, piping and gas boiler were developed based on parametric experiments of a floor heating system installed in a two-story wooden house build in a large chamber at BRI(Building Research Institute), changing experimental parameters such as temperature in the chamber, type of the piping, insulation of the floor and type of the boiler. It is shown that the proposed method can estimate steady-state energy consumption of hot water floor heating system with high accuracy by comparing energy consumption measured in the experiments with one calculated by the methods which is the combination of three calculation models.

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For estimating the energy consumption of a city that consists of numerous different sizes and types of building, it is necessary to estimate the distribution of the energy consumption of buildings in the urban area. The objective of this study is to estimate the household number and household composition of 22 patterns of household life cycle matrix using the co-hort factor method based on the population and regional econometric models. The case study was done for Toyohashi city, Japan. The energy consumption in the residential area was expected to be decreased for 50 years due to the decrease of population and high efficient energy supply system. The estimated household number was determined by the regional econometric model. The population would have decreased by approximately 20% compared with the present population in the central area around Toyohashi station and the population in suburb area would have slightly increased by 1.2%. The total energy consumption of the energy efficient house was expected to be decreased by 17.5% compared with the present level.

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The purpose of this study is to clarify the effect of agricultural irrigation pond on temperature. The irrigation ponds of which the measurements were carried out are located in Kakogawa city, Hyogo prefecture. Temperature, humidity, water temperature, and wind direction and speed were measured. The measurements were carried out from the beginning of July to the end of August in 2004.According to those measurements mentioned above, several results were obtained as follows.
First of all, the tendencies of the temperature formation are different especially in the daytime when the main wind direction is different. In addition, the wind direction can be separated into 2 types. One is from the landside. The another is from the seaside. Furthermore, the landside wind makes the temperature rise and seaside wind makes the temperature drop. Secondly, the difference of the temperature, formed at windward and leeward of the irrigation pond, shows its effects as cool spot in the daytime and heat spot at night. Thirdly, the factors which cause the temperature differences between windward and leeward are grasped by multiple linear regression analysis.
As the results, it is clarified that the difference between the temperature and water temperature affects the formation of temperature between the windward and the leeward at the irrigation pond.

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A field measurement on thermal balance and flow characteristics of a full-scale 2D canopy was done, and following phenomena were observed. 1) Air temperature distribution and sensible heat flux of canopy surfaces show the high irregularity due to the sunshade. 2) Linear relationships exist between wind speed U_1m and convective heat transfer coefficient (CHTC) of most measurement points. The linear regressions of SAT meters fixed on a leeward wall show similar tendency, in contrast those on a windward wall vary with the position. This tendency is consistent with those of former wind tunnnel experiments. 3) CHTCs of walls deduced from measurement result of surface thermal balance show different tendency of those of SAT meters. It may be caused by the effect of the unhomogeneous temperature distribution of canopy.

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Some researches show the results that an interaction exists on subjective evaluation between sound and visual environment. This study takes Taiwan for instance, and is to examine the effects of scenery on psychological evaluation while hearing environmental sounds. The results are as follows:
Evaluation of environmental sound is affected by not only the type of sound, but also the type of scenery. Comparing to the condition without any vision, the evaluation improved under the condition with the relative vision of scenery when hearing the sound. Natural scenery promoted the evaluation of environmental sound; however, artificial scenery reduced it. People like natural sounds and music, but dislike artificial sounds. Besides, the effect of environmental sound on evaluation is stronger than the effect of scenery.
This research shows that the visual sense also affects the audio sense. For creating a comfortable sound environment, we should place importance on not only audio factors but also visual ones.

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We conducted a survey on the occupants.. behavior, consciousness and lifestyle related to air-conditioning (AC) in apartment houses in Kyoto, Japan. The main results are as follows: 1) The necessity to shut the windows to avid rain was one of the reasons to increase the number of occupants who started using AC in rainy season. 2) The occupants who started using AC earlier were sensitive to heat. The occupants who started using AC later could stand heat and did not like to use AC. 3) The amount of time that occupants who started using AC earlier used AC and the period when they used AC were long. And the amount of time that occupants who started using air-conditioning later used electric fan were long.The custom to use electric fan might to make the using period of AC short. 4) The occupants who started using air-conditioning earlier prioritized thermal comfort. And the occupants who started using air-conditioning later prioritized economical life.

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The objective of this study is to propose a new method and system to control set point of air-conditioning system by using occupants' thermal requests with Building Consensus Logic that considers the balance between occupants' satisfactions and energy consumption. As already reported, the authors have proposed system architecture and basic logics of this control system. In this paper, “Women priority control logic” and “Heating control logic” are suggested as additional logics. A series of experiments was conducted in two offices building. It was confirmed that those control logics could enhance thermal satisfactions and improve indoor environment.

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According to the decline of the farming population, irrigation ponds are losing its values. However, the values of the irrigation ponds are not only for farming but also for some other purposes, such as recreation, regional landscape, historical place, and so on. For those reasons, to clarify the evolution structure in the consciousness of the inhabitants around irrigation pond is meaningful for reevaluation irrigation pond.
This study is based on the questionnaire survey carried out in 2003 and 2004. Two irrigation ponds in Kakogawa city were selected. For the comparison, two out of ten irrigation ponds in Higashihiroshima city were selected by cluster analysis from the surface ground conditions around. As the result of this study, the tendencies of the evaluation structure in Kakogawa city and Higashihiroshima city were clarified by using statistical method, such as factor loading matrix and multiple analysis.

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