Subjective experiment was conducted to identify the relationship between brightness sensation and the percentage of the subjects who turned on the ceiling luminaire in an experimental room which introduced diffused direct sunlight by using reflecting panel beside the window. Brightness sensation judged by the subjects just after they entered the room with diffused direct sunlight became higher than that without diffused direct sunlight. However diffused direct sunlight introduced into the room had no significant effects on the subjects' brightness sensation judged after they stayed in the room for 5 minutes. It was also identified that in the case when the illuminance on the desk was higher than about 200-400 lx, half of the subjects turned off the ceiling luminaire.

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The blind source separation and specification of location on time-frequency domain considering time lag information are conducted. The formulation based on the independency of time-frequency domain is presented. First of all, the number of source signals is specified. Next, the locations of source signals are specified. Then, the source signals are obtained. The numerical test is conducted to confirm our method, and then the locations of source signals and source signals are obtained by high accuracy.

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The development of blue color LED (Light Emitting Diode) made it possible to express manifold light colors by mixing the light colors such as red, green, and blue. The popularization of unusual light LED colors should get started owing to the development of blue color LED. The new light environment should bring about unexpected psychological and physiological effects and the basic research about light colors will be more necessary in the future. This research is about the psychological and physiological effects according to LED light colors and the purpose is to determine on the unpleasant range and pleasant range from LED light saturation. The research progressed by changing the saturation (up and down) of the three primary colors (Red, Green, Blue) and three compound colors (Yellow, Magenta, Cyan). All six species of light colors were used and the research progressed using two experiments color change and discomfort change. As a result, tint sensitivity and discomfort increase in case of approaching to pure color. In the range of feeling tint, the range of not feeling discomfort exists. The stage of evaluation of tint sensitivity and discomfort is specified to CIE 1931 Chromaticity diagram.

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The purpose of this research is to examine impressive elements of the Yamate Western-style Houses in Yokohama city, and consider how Christmas illuminations were used to promote the recognition of the place. First, a questionnaire survey was conducted to identify building elements which would be easily associated with the place. It was found that elements in characteristic shapes or in prominent places such as arches and balconies tended to be associated with the place. Next, the Christmas illuminations were experimentally set up. These did not illuminate entire buildings but rather parts of buildings. The energy consumption of the illuminations slightly exceeded that of the current flood lighting, but the total amount of luminous flux was much less. Furthermore, questionnaire survey s were conducted to investigate the psychological effects of the lighting. As a result, it was found that the elements that were most associated with the place were successfully picked out by the illuminations.

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A calculation method of transmission and reflection of glazing with Venetian blind has been proposed, taking into account not only specular transmission and reflection but also diffuse transmission and reflection. The proposed detailed calculation method was compared with the conventional simplified calculation method. Both of the calculations gave almost similar results, when the blinds were installed at the indoor side of glazing. However, non-negligible difference was found when blinds were installed at the outside of glazing, especially when the surface reflectance of the slats was large. As an application of the detailed method, calculation examples of the direction distribution of transmitted and reflected lights were also shown.

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A holistic numerical model to predict total utility demand such as thermal requirement, various energies, domestic hot water, and city water of a residential house or a set of dwellings like a residential building, a residential area and even a city was established, which we call Total Utility Demand Prediction System (TUD-PS). The system based on the methodology for generating actual inhabitants' behavior schedules with 15 minutes time-resolution, previously reported, and a dynamic thermal load calculation. The latter part of the model takes account into the probabilistic model for HVAC turning On/ Off events derived from the Markov Chain, also previously developed, which can realize to obtain probabilistic thermal requirement impacted by inhabitants' On/ Off behaviors. Simulation concerned on seasonal and peak loads for a single dwelling reveals that the so-called maximum load is phenomenally influenced by the assumption whether HVAC turning On/ Off events are probabilistic or deterministic. Hence, a spatial accumulated time-series of utility demands of respective dwellings must be predicted by the proposed model, where simultaneous dynamics of respective dwellings can be reproduced, at least, must not be applied a conventional and practical method where you predict a holistic demand by superposition of a demand at a typical and ideal dwelling.

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Even in relatively warm area in Japan, frost damage of roof tiles occurs. Our research deals with the frost damage from a thermal environmental point of view.
Condensation on the external surfaces of roof tiles, which is caused by a temperature drop due to nocturnal radiation, is estimated as one of the most important factors influencing the frost damage. The frequency of condensation and the amount of condensed water were calculated by a numerical analysis.
The influence of the parameters, such as the outside wind speed, inclination angle and the orientation of the roof, is investigated. It is clarified that a surface condensation on the roof tiles occurs very frequently even in a warm area of Japan.

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Development of a measuring unit for air flow volume within a natural ventilation system with the results of laboratory test and on-site measurement is described. As it was considered necessary to make a continuous, simultaneous multi-point measurement of a fluctuating air flow within the vertical shafts towards solar chimney in a natural ventilation system of a school building, a simple measuring system was devised. This system consists of pressure detector and data logger to be installed at several locations on site. The results of the field measurement agreed quite well with the laboratory test results so that the effects of the natural ventilation system with solar chimney could clearly be estimated. This measuring system could be used for measuring air volume in general multi-story buildings with natural ventilation system.

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A one-equation-type subgrid-scale model for a Large Eddy Simulation of plant canopy flows was proposed in this paper. The subgrid-scale kinetic energy equation was derived from the equations of continuity and Navier-Stokes. This subgrid-scale kinetic energy equation was closed by modeling several unknown terms which appeared in the equation. The present model was compared with an experiment of an open channel water flow where the open channel had a model plant canopy made of cylindrical rods. The present model well estimated the experimental value.

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This study investigated the effect of absorptive building materials in decreasing indoor concentration of formaldehyde by numerical simulation. Many studies have been reported on this subject, but most were limited to the investigation of one room. In this study, the numerical analysis models were based on the standard house of AIJ (Architectural Institute of Japan) to study the building material in full-size house. The performances of absorptive materials were compared by changing the surface area and position, and the most effective arrangement was studied. The case that absorptive materials were placed on the whole walls showed large effect of decreasing pollutant concentration compared to that without absorptive materials. It is also shown that installing absorptive building materials in the room with high formaldehyde oncentration is most effective. It can be concluded that the performance of decreasing formaldehyde is not determined by absorptive surface area proportionally and the layout of the absorptive materials is also important to achieve better effect.

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UVGI (Ultraviolet Germicidal Irradiation) system is recently considered for the sterilization of indoor air and practically applied to the buildings where need hygienic control mainly in America and Europe. In this study, the factors influencing the germicidal effect such as UV intensity and exposure time were reviewed and the several methods to evaluate the germicidal efficacy of UR (Upper Room)-UVGI system were introduced. The methods mainly use CFD simulation to calculate UV dose, considering the distribution of UV intensity of UR-UVGI system and the air flow induced by air handling system in a room. The methods were applied to a typical 4-patient ward model. Results showed that the positions of UR-UVGI system and supply or exhaust openings are important for UV dose. For example, spatial average UV dose decrease when UR-UVGI system is installed near the exhaust openings. Similar results were shown in the cases that the contaminants assumed to be exhausted from the mouth of patient. In the cases assuming infectious microbe flow in through supply openings or breathing of occupant, the germicidal efficacy of UR-UVGI could be evaluated with the methods.

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The findings of hearings and questionnaire surveys regarding waste collection points in municipalities are given in Part 1 of this report. The regulations for waste collection points varied by municipality, and within custodial spaces, each municipality had different regulations, especially regarding recyclable items. In the present report, a survey was conducted to ascertain the actual conditions of waste collection points at office buildings, and a waste collection planning method that supports resource recovery is proposed based on the those results, with the following findings.
1) According to the survey, even among buildings reporting adequate space for waste collection points, respondents reported insufficient working space for waste separation.
2) There were about 11 separated waste groups at surveyed buildings after excluding waste groups specific to individual buildings. Of the various separated waste groups, groups for paper, cans and bottles were established at all buildings, but there were differences in the handling of types of plastics.
3) When investigating custodial space use, it is important to account for the apparent specific volume of waste, the differences in storage containers, and the number of separated waste groups.
4) With the proposed planning method, by selecting proper storage containers based on waste volume and properties, custodial spaces can be arranged in a rational manner to ensure sufficient working space for waste separation.

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There are two factors to decide proper capacity and structure of oil-interceptor. One is the factor which flows in the interceptor and another is factor which exists in the interceptor itself. As for the inflow factor, suggestion performance criterion based on carwash experiment was already made. Therefore in this report regarding factor in the interceptor itself, several experiments, that used pure proper lard instead of oil, have been made and as a result, it could get performance criterion which can be a fundamental vale.

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This study aims to clarify the actual installing conditions of heating, ventilating, and air-conditioning (HVAC) systems and their operations in public elementary schools based on 568 school data obtained from a nation wide investigation. Some results are shown as follows: 1) Insufficient thermal insulation and air tightness were provided in many school buildings in warm climate areas, 2) Heating systems were provided in almost all rooms but their installing conditions varied with respective areas, 3) Air-conditioning systems for cooling are on the increase in many areas, especially urban areas, and 4) Ventilating systems are not operated under optimum conditions because of inadequate management. We suggest that the building envelope systems should be improved and it is necessary to make guidelines and inform teachers of the essentials of maintenance for HVAC systems for efficient operation.

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This paper presents effects of perimeterless air conditioning system on indoor thermal environment and energy conservation in the office building by long-term actual measurement. It is verified that the high-performance window system including automatic external venetian blind and glass with heating layer enables perimeterless environment through all seasons, and advanced air conditioning system including low-temperature air supply applying Sock filter and VAV realize comfortable indoor environment and energy conservation. It is also shown that tuning and refining of the system based on measurement and verification in the actual condition contribute greatly to the effective operation.

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