The objective of this study is to describe room shapes of concert halls quantitatively and to evaluate them objectively. Room shapes in horizontal cross section were described using elliptic Fourier descriptor, and these characteristics can be detected quantitatively. Based on the results, we propose the following: 1) Wavelength and amplitude included in a shape can be calculated from Fourier descriptor. 2) The spatial frequency characteristics expressed as the ratio of the amplitude to wavelength (RAW) enable us to detect the spatial frequency that greatly influences the shape. 3) Room shapes in horizontal cross section can be quantitatively compared using Principal Component Analysis which uses normalized Fourier descriptors.

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Krylov subspace iterative solvers are applied to large-scale finite element sound field analyses of architectural rooms. First, convergence behaviors are compared among four iterative solvers. Results show that Conjugate Orthogonal Conjugate Gradient (COCG) method offers the best characteristics for finite-element (FE) analysis from the viewpoint of robustness of convergence and computation time. Then, two investigations to reduce computation time of the COCG method were carried out. Results show the following. (1) The averaged residual of sound pressure levels between COCG method and direct method are less than 0.1dB if the convergence criterion is set to 10^<-4> and the maximum residual of those between COCG method and direct method is less than 0.2dB if the convergence criterion is set to 10^<-6>. (2) The computation time of the COCG method with diagonal preconditioning is about 30% shorter than that of COCG method without preconditioning. Finally, sound pressure level distributions obtained using the authors' FEM are compared with those obtained by fast multipole BEM (FMBEM) and measurements.

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This research focused on the advance perception of nighttime intersections in Yatsuo Town in Toyama City. The research considered an ideal street lighting method taking into consideration danger avoidance and regional characteristics. First, the present situation regarding the perception of intersections in the town was evaluated. The result showed that many narrow crossroads were not perceived easily at night, and it was found that the visibility of the crossroad outline and the corner buildings was important in perceiving crossroads in advance. Next, a new lighting environment at an intersection was created experimentally using small light sources, and it was found that these lights harmonized with the streetscape and also succeeded in helping drivers to perceive the intersection earlier.

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The effect of evaporative cooling of three kinds of water-absorbing percolation asphalts which made for trial purpose has been examined and it has been found that there is little water absorbing capacity of the percolation asphalt and the water-absorbing percolation asphalt has water absorbing capacity of 5cm at least and the content of barmicurait has a big influence on the water absorbing property. Since these experimental materials used are those immediately after making, the influence of the moisture transfer over along time on the behavior of cement in the sample has not been considered. In the present paper, the deterioration with age of the evaporation performance of the water-absorbing percolation asphalts is examined. The surface temperature and the amount of evaporation are numerically investigated under the same condition with experiment. The influence of moist transfer coefficient on the insolating wet surface temperature of the materials is also examined.

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This paper deals with prediction of heat transfer on internal blinds by Computational Fluid Dynamics(CFD). Tests were conducted to collect detailed data around blinds for the cooling and heating conditions. Test cases include those with different slat angles and those with and without a supply slit below the blinds. Convective heat was estimated from heat balance equations on the slats using radiative heat derived from measured surface temperatures and absorption factors. CFD calculations were made using a low-Reynolds k-ε turbulence model in order to predict convective heat and convective heat transfer coefficients on the blinds and the calculated results were compared with the test results. The results of the comparison demonstrate that calculated distributions of convective heat and convective heat transfer coefficients on the blinds correspond well with the test results for both the cooling and heating conditions. Convective and radiative heat flows and convective heat transfer coefficients on each surface were also analyzed in detail from a macroscopic point of view.

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Current moisture guidelines for building envelopes employ specification standards, which specify the types and the details of building assemblies. However, required performances to avoid moisture damages within building envelopes should be clarified in terms of performance standards. Taking these back grounds into account, we already proposed a framework of a practical design method based on the frequency of relative humidity within wooden wall assemblies in the previous paper of this research. In this paper, a regression model to predict the excess frequency of the relative humidity is proposed by statistical analysis of simulation results of a one-dimensional HAM model. Moisture resistance ratio that is one of the design parameters to determine wall specifications can be derived from the model. Accuracy of the model was examined in comparison with the precise values regarding the excess frequency. Furthermore relation between the moisture resistance ratios and climate conditions was discussed in terms of regional classification based on the required performances.

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We conducted wind tunnel experiments with simple-shaped block models to study the relationship between the widths of connecting streets across a street canyon and the flow and concentration of roadside air pollution within the street canyon. The main results are as follows: 1) The concentration in the vertical section along the central part of the street canyon increases as the widths of gaps or connecting streets decrease. 2) The vertical concentration distribution within the connecting street implies the existence of a vertical vortex, which was pushed outwards from inside the street canyon. 3) The lateral flow parallel to the main street greatly affects the concentration in the connecting streets.

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This paper addresses the effects of fault and optimization of PID parameters in building air-conditioning systems. On setting disorder of PID parameters, the influence was made clear through experiments. It produced hunting at valve and increased ON/OFF frequency of the chiller larger than the difference of electricity consumption and the room's temperature fluctuation, etc. So we can say it is considered that the setting disorder is not noticed, even if only the room's temperature and electricity consumption are watched. On the optimization of PID parameters, optimum adjusting strategy using Genetic Algorithm (GA) was proposed. The strategy simultaneously searches PID parameters of VWV 2-way valve and VAV units. We verified the usefulness of the strategy.

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This paper presents the effective operation methods and the regional energy conservation effects of housing Polymer Electrolyte Fuel Cell Co-Generation System (PEFC-CGS). We built the model-based simulation program to calculate the energy budget in a case that PEFC-CGS was introduced to detached houses considering specifications of a real PEFC-CGS. As a result of model-based simulations, we found that DSS (Daily Start and Stop) operation was the most effective method. Energy conservation effect is higher in cold areas because it varies by quantity of hot water supply load. The primary energy consumptions are reduced by 4-13% and CO_2 emissions are reduced by 7-20% in Japan. These values are increased by 1-2% in a case of the reverse power flow. Utility costs are also reduced by PEFC-CGS, but they vary by payment setting in each area.

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An outdoors experiment was launched for the development of an evaporative cooling pavement system and simulation model in the previous paper (Part 1). In this paper (Part 2), the characteristics of heat and water balance on this evaporative cooling pavement were investigated with a focus on surface wet condition and water content of the pavement. This analysis was conducted using empirical data of sunny and cloudy daytime conditions throughout a year. The results from this study showed the following: (1) Surface wet condition has a large impact on the evaporation and surface temperature of the pavement. (2) There is a correlation between water content and surface wet condition. (3) There is a correlation between water content and vertical water content distribution. These results indicate that surface wet condition depends on water content of the pavement during daytime. This finding is significant and meaningful for the modeling of heat and water balance on evaporative cooling pavement systems.

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The objective is to clarify the influence of CO_2 emission caused by the equipment in the wooden detached house. In this study; pipings, wirings, furnishings, home electric appliances and furniture were defined as 'equipment'. The result showed that CO_2 emission related to manufacturing process of the equipment was about 20%. And with the using process of the equipment included, it was shown that CO_2 emission caused by it occupied 60-80%. In addition, dipending on the specification differences in selected equipment, it was caught that the result of LCCO_2 varied within about 10%.

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The energy consumption in Japanese houses is increasing rapidly, and it's effective saving method and minute investigations are needed. We carried out detailed load survey on actual houses in Kanto district, 9 detached houses and 5 apartment houses. Electricity was measured for air conditioning, hot water, and main each house appliances. Usage estimation was applied for measured gas volume. The main usage in total annual energy consumption is air-conditioning and hot-water. On the analysis using correlation and covariance, we found that energy consumption's difference between houses and seasonal fluctuations are mainly caused by air-conditioning, hot-water and lighting.

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In order to stabilization of the energy supply and demand in residential area, it is important to grasp of the peak energy consumption. In this paper, we examine the peak electricity, frequency distribution of peak electricity, day-load-rate and outbreak time in 6 detached houses based on measurements for energy consumption. In conclusion, 1) In all electrified houses, the outbreak time of peak electricity concentrate in midnight. On the other hand, it is distributed wide time in houses that use electricity, gas and kerosene. 2) The peak electricity in all electrified houses changes by a season and in houses that use electricity, gas and kerosene change by a day. 3) A distribution range of the peak electricity annual frequency is wide in all electrified houses.4) Day-load-rate decreases to the summer in all electrified houses and changes by a day in houses that use electricity, gas and kerosene.

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To induce whether we can obtain a sustainable society shifting our paradigm from the materialism to the eco-conscious idea, a 'universal' prototype model for Environmental Dilemma Game was established, which is one of the authors' series study for the modeling of Human-Environmental-Social System. The meaning of 'universal' comes from the fact that the presented model is obviously different from the previous environmental dilemma games in two points. The first feature is that the recourse restriction is exogenously defined from the inherent game structure (payoff structure) so that the environmental recovery rate can be estimated in time varying way, which differs from n-Chicken type or Tragedy of Commons (TOC) game. The second point is that the game played by agents is defined by a 2×2 game that is standard, well known, widely researched as a prototype game. A series of simulations reveals that a sustainable strategy allowing behavior-shifting to adjust environmental capability can be evolved in a limited region of the 2×2 game world, where game's dilemma is rather weak. Whereas, a set of dangerous strategies always trying to obtain resources has been prevailed.

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