A subjective experiment on listener envelopment (LEV) was carried out using synthesized sound fields in an anechoic room. The results are as follows. 1) The largest LEV was observed around azimuth 90 degree as to arriving direction of reverberation. 2) Longer reverberation time makes LEV larger. 3) Larger energy of reverberation makes LEV larger. 4) Left-to-right imbalance of reverberant energy makes LEV smaller. 5) Front-to-back imbalance of reverberant energy makes LEV smaller. 6) Reverberation arriving from frontal direction makes LEV larger than from behind. The results 1) to 5) generally coincide with previous works, but result 6) differs from them. Based on these results, SDR (spatial distribution of reverberation) was proposed as a measure of LEV. SDR shows higher correlation with the experimental results on LEV than already proposed measure LG by Bradley or SBTs by Hanyu.

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Finite-difference time-domain (FDTD) acoustic simulation technique in generalized curvilinear coordinates using contravariant velocity and pressure as variables for two-step leapfrog time marching scheme is presented. The technique excels the conventional generalized curvilinear technique using contravariant velocity, covariant velocity and pressure as variables for three-step time marching, especially in that normal acoustic impedance boundary conditions which are indispensable in practical application are also presented. Validation of the technique through comparison against orthogonal FDTD with staircasing applied in irregularly-shaped sound field shows suppressions of phase error in initial time marching stage and diffusion from staircased boundaries.

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This paper presents a proposal of phase interference method for reduction of multiple excitation force. Firstly, conventional vibration reduction methods are discussed, mainly on the merits of general elastic suspension methods and on their demerits of difficulties on reduction of lower frequency vibration components. Secondly, a new method of vibration reduction is presented which is effective on lower frequency vibration case. Theoretical reduction effects of it are studied and differences from conventional isolation methods are discussed. Finally, practical effects and feasibilities of the newly presented method are studied and discussed, considering of various application situations on the building vibration-proof engineering.

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The purpose of this study is to examine illumination levels and balances of street and shop lighting in a commercial street during shop opening hours and after closing time. An experiment to coordinate light quantities of a street and shops was carried out in each time zone. The principle results were summarized as follows. 1. The minimum illuminance and luminous flux levels for the street were different according to the type of shop lights and color of street lights. 2. When the strength and colors of shop lighting were harmonious than the present heterogeneous condition, the total illuminance or luminous flux could be set lower. 3. The ratio of street lighting to shop lighting was higher when the color temperature of street lights was low. This tendency appeared strongly in the minimum required lighting level after the shops' closing time.

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The human thermoregulation model COM (Complex Thermal Environment Comfort Model) was developed, incorporating the blood flow model for extremities and the conductive heat transfer model at contacting skin surfaces. The whole body model has 17 body segments, each consisting of 2 compartments for core and skin. Each core compartment of extremities has artery and vein blood pool in its center. The central blood compartment exchanges heat with blood pools and the tissues except extremities. The heat balance equations for each tissue are described. The current model is able to predict fairly well for the body temperature distribution under unsteady state conditions.

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The aim of this study is to verify qualities of indoor thermal environment and heating energy consumption through this research on highly insulated buildings introduced reduction systems of fresh air load in cold regions. The research objects are two government offices for outside insulated RC buildings newly built in Obihiro City and Hakodate City. We consider the temperature characteristics on effects of high heat insulation and thermal storage in buildings, and the heating systems and control techniques on operations for highly insulated buildings. Also we consider the effects of energy reduction and usefulness on introductions of reduction systems of fresh air load. Based on what we have learned through this research, we discuss the subjects and suggestions for highly insulated buildings in cold regions.

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The several error factors are included in the separations of global solar irradiance into direct and diffuse components, and the factor of short-term solar fluctuation is taken as an example. In this paper, we propose the new index for properties of short-term solar fluctuation, and indicate the characteristics how the index is occurred in actual and virtual weather conditions. We examine the round off errors of peak integrating solar irradiance, the prediction accuracy of direct-to-global irradiance, etc., with much of short-term fluctuation.

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To clarify the feasibility of passive heating for residences in China, the heating degree-days were computed using the observational database. A model for the monthly solar radiation was improved by adding the parameter of outdoor temperature difference between the highest and the lowest. The potential of passive heating for residences was defined as the ratio of accumulative solar radiation during the heating season to heating degree-days. The regional characteristics of potential of passive heating for residences in China were clarified by making a map with contour lines of the ratio of radiation to degree-days.

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Network models of a hybrid ventilation system for multifamily dwellings were constructed. The following prediction results were checked by the experimental results. 1) Fresh air supply rate during the operation of the auxiliary fan 2) The ratio of the time when the auxiliary fan works 3) Fresh air supply rate of the hybrid ventilation system during the wind induced ventilation and mechanical ventilation by the auxiliary fan System parameters of the hybrid ventilation system, such as pressure loss of the ducting system, the capacity of the auxiliary fan, the operation criteria of the fan (air speed in the duct), can be optimized by the prediction method developed in this research.

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Recently, the "sickhouse" has been attracted as our urgent problem. The domestic air cleaners have been widely used as a pollution mitigation measure in Japan. The removal efficiency of domestic air cleaners on some pollutants has been reported. Though we have already reported the formaldehyde removal rates on the domestic air cleaners, the detailed reports concerned with the VOC removal aren't provided yet. So, this study was carried out to comfirm the 22 VOCs removal rates of the equipments. From our results, it turned out that the VOC removal rates of the air cleaners with a rich activated carbon filters were ranged from 14.6 to 18.3 [m^3/h] by the equipment index of ECAR (Equivalent clean air rates) and the VOC ones of the electrostatic type units were only a little less than 1.40 [m^3/h].

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Full-scale chamber of test house was used to investigate emission data of terpenes from cypress wood and pine wood. This experiment involved placing samples of the specimens and an ozone generator in one room of the test house. The major terpene emitted from the specimens was pinene<alpha->. The indoor concentration of pinene<alpha-> with ozone emission was much lower than that without ozone emission. It was found that the higher the indoor ozone concentration, the lower the concentration of pinene<alpha->. The pinene<alpha-> might have been consumed by the reaction with ozone during the experiment. The concentrations of acetaldehyde were not changed regardless of the change of ozone concentration for both specimens. On the other hand, the concentration of formaldehyde with high emission of ozone was fairly higher than that without ozone emission for the specimen of cypress wood.

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Now believed to be responsible for anaphylaxis to chemical substances, concentration of formaldehyde (HCHO) and volatile organic compounds (VOCs) given off by interior finishing materials and furniture is very low in residential spaces.To accurately measure this concentration, it is necessary to concentrate the air sample during sampling and to employ high-precision analyzers such as a gas chromatographic (GC) analyzer and a GC Mass Spectrometer (GC/MS) to obtain the results. Since these complicated sampling and analytical operations require a high-level of expertise, the development of an on-the-spot precise measuring instrument has long been awaited. This study examines the application of a semiconductor-based odor sensor capable of measuring andevaluating TVOC (total VOCs) levels in low concentrations quickly and in a timed sequence. To evaluate the characteristics of the sensor, the results of the measurements were compared with results obtained from a GC analyzer and/or a GC/MS. A relatively good correlation was obtained between the results, indicating the sensor can be used to develop an effective complementary system to enhance the analyzers.

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This paper proposed three types of cooling design weather data, the h-t basis data, Jc-t basis and the Js-t basis data. They were produced from the weather values on the extreme-weather days selected out of Expanded AMeDAS weather data from 1981 through 2000 using the two weather indices. The extremity of the proposed design weather data were evaluated obtaining the cumulative frequencies of occurrence of the daily weather values and the probabilities of occurrence of the thermal load exceeding the cooling design load calculated with the proposed weather data.

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The aims of this study are to verify the optimum operation methods and the indoor comfort about thermal storage heating and cooling systems consisting of piping laid inside the floor for highly insulated buildings based on simplified predictive control. Principally, We consider the usefulness of continuous and nighttime operations on the basis of energy consumption for heating and cooling systems and indoor environment. As a result, the operation methods of equivalent for continuity like continuous and nighttime operations were effective for the problem of stopping operations on Saturday and Sunday in heating season. But stopping operations on Saturday and Sunday & continuous operations on weekdays was irrational. The operation methods of equivalent for intermittence like intermittent and nighttime operations were effective for the problem of rising room temperature during daytime in cooling season.

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The growing energy consumption of commercial buildings in the field of civilian sector strongly requires to take effective energy saving measures. Especially as the energy consumption of heat source system in office buildings occupies as high as about 30% of the total building energy consumption, the efficiency of the heat source system should urgently be upgraded. For this purpose, it is essential to grasp the annual thermal load fluctuation and corresponding operation status of the heat source system for analysis. At present, however, the examples of measurement survey of the energy efficiency ratio of the system in commercial buildings can scarcely be found. Backed by such circumstance as above, this study conducted actual measurement on the heat generation and energy consumption of the heat source system in three typical commercial buildings to grasp the operation status and energy efficiency ratio by employing the system COP as a performance index.

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The water leakages due to corrosion occurred from the dry sprinkler piping and the wet sprinkler piping which both are galvanized steel pipes after 1.5 year and one years of use respectively. The cause of corrosion was investigated by the electrochemical analysis of the cut sample pipes and the reproduction experiments. It was clarified that the cause of corrosion depended on the reversal phenomenon of electrical potential between the zinc and the steel, and the high density of dissolved oxygen caused by high pressure in piping. For preventing corrosion, the water in dry sprinkler piping should be pulling out and the airs in dry and wet sprinkler piping should be substituted for nitrogen.

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This study aims at quantitative investigation of the radiative temperature distributions in detail for the Osaka central area, by overlaying airborne thermal image with GIS data. Principal findings we have described this report are the following.(1) In the park, the radiative temperature of "Grass" is lower.(2) In the water area, the radiative temperature of the large river is lower.(3) On the wide east-west road, the radiative temperature on the north side of the road is higher than that of south side.(4) The radiative temperature of the intersections is higher than that of other road areas.

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This study is on the reproductivity of the visual environment by the dynamic simulation displayed on the wide screen. The result shows that a sense of reality is highly influenced by the modeling accuracy and supplemented by speeding up the moving velocity if the modeling accuracy is low. On the other hand, the quality of the mesh division and the resolution of the texture for mapping do not influence a sense of reality so much under the circumstances of this study.

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The purpose of this study is to clarify the usefulness concerning the survey in free descriptive answer style and the evaluation process to decide whether preferable or not, against the familiar regional landscapes recalled by the subjects. First of all, a questionnaire survey on preferable and dis-preferable landscapes in free descriptive answer style to the students of Hiroshima University as subjects was carried out. As for the analysis method of the answers, they were divided into three components, such as 'main object','condition of the object' and 'reason for the decision'. As a result of the survey, the fact that the subjects recalled not only the specific landscape elements, such as trees and buildings, but also the variety combination of landscape elements and whole image of landscapes was found out. In addition, the process of landscape evaluation was grasped by the fact that the relationships between each 'main object' and 'reason for the decision' have the feature which prompts to decide whether preferable or not. On the other hand, we clarified that 'main object' and 'reason for the decision' have the strong effect for separating the landscapes into two groups. However,'condition of the object' does not have such effect because it is the supplements for 'main object'.

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This research examined experimentally the effects of lighting colors and types of background music on conversational behavior at a cafe. When each table was occupied by same sex friends in the laboratory assumed as a cafe, the effect of the background music on their behavior was strong, but the effect of the lighting colors was weak. That is, when the tempo of the background music was fast there was a tendency for eye contact, the amount of conversation, and the conversational volume to increase. The lighting colors were important in regard to providing sufficient illumination for conversation partners to see each other's faces. Ease of talking was affected both by lighting colors and background music. The evaluation was more favorable with the use of general white lighting and with background music of an intermediate tempo, such as bossa nova and ballad style music.

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Recently, wireless LAN is widely used around/inside building, and some problems have been appeared, such as multi path fading or security. Some EM-wave absorbers are proposed to solve above problems. In this situation, three layer type absorber by using common building materials is presented. In this paper, first three steps of design procedure are introduced. Secondary, the frequency of the temperature and relative humidity for the experimental room are investigated in order to estimate the condition of setting environment, and the variation of the water contents for the fiber reinforced cement boards are estimated. Lastly, comparison of measured absorption and calculated one for experimental absorber to confirm the validity of the design procedure and effectiveness of the absorber. Recently, wireless LAN is widely used around/inside building, and some problems have been appeared, such as multi-path fading or security. Some wave absorbers are proposed to solve these problems as a one of the counter plan. In this situation, we presented the three layers type absorber by only common building materials (the Absorber) to propose the better wireless communication environment, while other absorber is expensive and difficult for handling, comparing common building materials. The target of the absorption is 12dB for two major wireless LAN frequency ranges up to 30 degree of TE and TM polarization wave including normal incident. The Absorber has advantage of cost and handling, and absorber with two layers is widely known to have two absorption peaks. Most of building materials, however, have very low absorption, especially for oblique incident, even with two layers structure. So, we try to insert air layer into two building materials to increase the performance. Fig.1 shows the basic structure of the Absorber. Fig.2 shows the design procedure of the Absorber. The absorption of the Absorber could be calculated by gradually electric circuit equivalent equations with 9 unknown factors (3 thicknesses, 3 real parts and 3 imaginary parts for complex permittivities). By linear relationship between complex permittivity (real and imaginary) and water content in certain range (typically 5-10%) shown in Fig.3, 9 factors can be reduced to 5 unknown factors (3 thicknesses and 2 water contents). Table 1 shows the combination ranges for each layer and water content for type A, which can be over 12dB absorption, as results of the calculation for the Absorber by fiber reinforced cement board. As the first step, the course calculations are conducted in the range of 0 to 30mm, 0.1mm step for each layer and 5% to 10%, 0.1% step for water content. Selected number in the table means the number of combinations of three thicknesses and two water contents satisfied the target absorption (12dB for up to 30 degree TE and TM oblique incident). The results of course survey indicated only two combination ranges for type A could be over the 12dB among wide survey ranges for two types of fiber reinforced cement board, and case 1 have narrow ranges for d_1 and d_2, comparing that for d_3, and also have narrow ranges for wc_3 comparing that for wc_1. Next, fine calculations are conducted to fix the thickness of each layer for the design of the Absorber. Table 2 and Table 3 show the fixing procedure for the thickness of the layer in the order of narrow range. The results of the fine calculation indicate fixed combination for case 1 has wide range for wc_1 comparing that for case 2. This property is suitable for the Absorber, because layer 1 is more affected to the variation of temperature and humidity in the setting environment than layer 3. Fig. 4 and Fig.6 show the area of water content of each layer over 12dB and 10dB, respectively, and Fig.5 shows frequency characteristics of the Absorber. The frequency of the temperature and relative humidity for the experimental room are also investigated in order to estimate

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The adsorption process on the Si wafer was investigated by using molecular mechanics (MM), molecular dynamics (MD), Monte Carlo (MC), and computer graphics. The adsorption energy of organic gaseous contaminants, such as dibutyl phthalate (DBP), dioctyl phthalate (DOP) and low molecular-weight cyclosiloxane (LMCS), on the hydrogen terminated Si surface and its oxide surface, were estimated and compared. The amount of saturated adsorption onto silicon wafer was also calculated. The adsorption isotherm of airborne molecular contaminants, such as dibutyl phthalate (DBP), dioctyl phthalate (DOP) and low molecular-weight cyclosiloxane (LMCS), onto the oxide surface of Si wafer, were estimated and compared. It indicated that the configuration of the adsorbed DBP molecules over its gas concentration of 1.9 μg/m^3 showed multi-layer adsorption. It was indicated that adsorption energy and the amount of the saturated adsorption is a good index to estimate the adsorption properties of organic molecules.

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