Design of sound environment of urban shopping arcades is important for promotion of a lively atmosphere and better speech/sound transmission. In this study sound environments in arcades of two cities were surveyed for 1) sound levels and audible distances of sounds from loudspeakers, 2) time of day variation of the sound environment with regard to sound levels and types of audible sounds, and 3) reverberation characteristics. The results were: 1) loudspeakers were widely used and sometimes set toward the street; 2) L_<Aeq> values in the arcades were around 70dB in the daytime; 3) The reverberation times were around 1.5 seconds at 500Hz when stores opened.

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This paper shows the result of study on measured excitation force of one person, considering the typical concert audience action and/or tempo of tune. Referring to the result, human action might be classified into three modes, those are, jump mode, TATENORI action mode, and bend and stretch mode. In addition, taking harmonics of fundamental excitation force component into account, the maximum values of excitation forces are shown on each frequency harmonic components, which might have influence on the floor of concert hall during live-concert is given.

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Evaluation of thermal performance of fenestration system under cooling season is based on heat gains by temperature difference and solar radiation, characterized by thermal transmittance (U-value) and solar heat gain coefficient (SHGC), respectively. However, current test methods are only concerned with nighttime performance, and may not accurately reflect the performance improvements of specific window designs. With nighttime test methods, the thermal performance of a fenestration system is characterized only by the U-value. In this paper, a new test method has been developed to measure the thermal performance of fenestration systems. This method enables the determination of SHGC and U-value for various fenestration systems under cooling season, including integral shading devices and complex frame designs.

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The present paper describes the framework of a practical design method based on frequency of relative humidity within wooden wall assemblies. In this practical design method, moisture resistance ratio across the outer surface of a thermal insulation material is employed as a principle design parameter for the wall assemblies. One of the features of this method is that the design parameter can be calculated without hygrothermal simulations. Instead, two equations regarding the excess frequency of relative humidity are determined by statistical analysis of simulation results of a one-dimensional HAM model developed by authors. As a first step of the research, laboratory experiments using full scale specimens were implemented to validate experimentally the HAM model for this study. Furthermore impact of variability of moisture permeability related to relative humidity was examined for the practical design method.

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Large-eddy simulation is applied to the problem of atmospheric dispersion inside urban area for oncoming turbulence, which is time-sequentially generated by unsteady numerical simulation of spatially-developing boundary layer in the driver unit as another computational domain. The present numerical model is validated in comparison with the previous field experimental results for plume dispersion through regular arrays of roughness blocks. We investigate the characteristics of flow and plume dispersion in actual urban area and occurrence of peak-to-r.m.s. concentrations based on various kinds of surface roughness for safety analysis. Obtained results are as follows; 1) The patterns of spatial distribution of mean concentration in actual urban area is very different from those in regular arrays of roughness blocks. 2) Fluctuating concentrations in actual urban area have special features, which can not be explained by the physical mechanism of the dispersion process obtained in regular arrays of roughness blocks.

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Concentrations of acetaldehyde and the ventilation rates were measured in an experimental house for three years. And the emission rates from the materials were measured using small chambers. 1) The concentrations of acetaldehyde changed with the temperature for three years. 2) The influence of the temperature and the concentration upon the emission rate of acetaldehyde was lower than the influence in the case of formaldehyde. 3) The emission rates of acetaldehyde from the materials in three years were as same as the rate from the materials in two years.

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This paper reports the in situ experimental results about the influence on concentration of airborne microorganisms, volatile organic compounds and aldehyde by air ions generated from an ion generator installed in an air conditioning system equipped in a super-high-rise commercial building located in Shanghai, China. Although the concentration of positive air ion and negative air ion raised up to 2.3 times and 1.9 times, respectively, by the operation of the ion generator, there was no reduction of the concentration in any of airborne microorganisms, volatile organic compounds and aldehyde.

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It is examined as a standard for the Micro chamber method to measure SVOC emitted from building materials. DEHP is classified as SVOC and widely used as plasticizers in polyvinyl chloride (PVC). The indoor guideline of the Japan Ministry of Health, Labour and Welfare for DEHP was set at 120μg/m^3. In this study, the authors measured DEHP emitted from PVC wallpaper and flooring using the Micro chamber method. And we evaluated various experiments concerning this method. In these experiments we found that the silylation of the internal chamber surface was effectively in the measurement of SVOC emitted.

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In recent years, hospital infection problem is drawing a social attention. About the indoor air environment in a hospital, although several reports on the indoor airborne microbes in large hospitals have been published, and the actual status of airborne microbial concentration is reported in detail, there are few papers on the behavior of airborne microbes in small hospitals which are numerically more than the large hospitals. This paper reports the results obtained by 1-year field measurements in a small hospital located in Aichi province, Japan. The main conclusions are as follows. (1) The indoor airborne microbe concentration in the survey hospital, where natural ventilation system was adopted, shows the variations on the changes of indoor air temperature and relative humidity through one year. (2) Since the airborne bacteria concentrations in the waiting room and the consulting room were almost the same concentration through the year, the possibility of cross contamination was suggested. (3) From the viewpoint of removal of the airborne microbes, it is desirable to install an air cleaning device in the survey hospital.

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The control strategy for the supplement fan and the damper of hybrid ventilation system is very important point of the system performance. The hybrid ventilation system using a pressure difference sensor for monitoring the exhaust airflow rate and two air supply systems were installed on a test house. Performance of this ventilation system was evaluated through the field measurement. The results of the measurements revealed that the exhaust airflow rate was relatively stable while the indoor-outdoor temperature difference varied and the wind velocity changed. The air supply system through the crawl space(Case B) showed better results for the stability of exhaust airflow rate against the outdoor environment than the passive air supply system (Case A). Totally, the exhaust airflow rate of Case A, Case B met almost the target airflow rate in 60%, 69% of the measuring period respectively. Case B showed better result about the balance of ventilation airflow rate of the first and the second floor, too.

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This paper describes whether its air conditioning system functions properly and achieves the energy saving and reduction of loads on environment. The air conditioning system is featured by the system composed of under-floor air conditioning and natural ventilation in combination and equipped with ceiling fans. The natural ventilation rate and cooling rate due to natural ventilation were estimated through the analysis of the field measurements results.

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We assessed the performance of a commercial jokaso system with a membrane in treating domestic wastewater, including wastewater from garbage disposal systems. We then sprinkled the treated wastewater over sedum propagated on the rooftop of a building to evaluate the ability of the plant to remove phosphorus and nitrogen from the wastewater. In a 6-month demonstration test the membrane-treated wastewater showed stable qualities, with low BOD and SS, for example. There were only low counts of Escherichia coli, and no Legionella bacteria were observed. Furthermore, the phosphorus and nitrogen in the water applied to the rooftop greening were absorbed by the sedum. Rates of removal were phosphorus (66%) and nitrogen (55%). Unlike discharging the wastewater directly to a river, spraying treated wastewater onto the sedum reduced the phosphorus and nitrogen contents. In addition, the final effluent from the rooftop greening had a low concentration of organics, with an average pH of 8.3 and no observable Legionella, so percolation of the effluent through the soil and utilizing it as recycled water presented no problems. Finally, we estimated the water balance of the rooftop greening system using a jokaso system with membrane and offered two model cases.

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We provided a household with a combined treatment-type jokaso system that could treat garbage disposer wastewater and then tested the usefulness of the treated water and excess sludge generated from the jokaso system. Water treated with the tank was used for toilet flushing, car washing, and field irrigation. Excess sludge in the jokaso system was extracted as scum, fermented for a certain period, and then used as compost for the cultivation of corn. The treated water was of good quality. About 13% of the water was utilized for toilet flushing, whereas only a very small amount was used for car washing and field irrigation. In addition, the compost generated from the scum had a nitrogen content of 2.3%, a phosphorus content of 0.8%, and a potassium content of 0.69%. Corn grown using this compost had a low yield because of a poor balance of nitrogen, phosphorus, and potassium. To increase the corn yield it would be necessary to improve this balance by adding phosphorus and potassium to the fertilizer.

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The investment of building construction industry in Japan is about 20% of GDP. This fraction is much higher than in most developed countries. That results the Japanese building construction industry including residential use consumes about one third of all energy and resources of the entire industrial sectors. In order to save energy as well as resource, the recycle of the building materials should be urgent to be carried out In this research, we try to make clear the process of the building demolition construction and to present a method to predict the energy consumption for recycling the building demolition materials. Firstly, we have a questionnaire and field survey on the dismantling and intermediate processing enterprises. Secondly based on the field study, we focus on the potential energy savings with a simple calculated method when the building materials or products are manufactured from recycled materials. The results have shown for most building materials, the energy consumption needed to remake housing materials from recycled materials is lower than that to make new housing materials. The energy consumption of building materials in all case-studies can be saved up to 13%. At the same time, the resource, measured by mass of building materials (kg) can be decreased significantly.

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This paper examines the relationship between energy saving economy in a building facility and the price of CO_2 emission right which is supplied by CDM project like the afforestation, including the case assuming the introduction of carbon tax. The expression of the turning point whether to adopt the energy saving system that the deficit is caused in LCC or to buy the CO_2 emission right is derived. The expression that expresses the upper limit of investment for reducing CO_2 emission from the viewpoint of securing the social meaning is also derived. Using the approximate values, the relationship between energy saving economy and CO_2 emission right price is examined. A problem of the carbon tax as the environment policy is pointed out by this study.

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Demolition work which is used by mechanical equipment, or gas cutting of members by a manual technique is mainly used for finishing materials and building steel structures. Depending on the case, demolition work is carried out sequentially from a part of structure easily demolished. Here, we propose careful demolition of column-girder connection arranged for low-storied steel structures in reverse order of a conventional erection, which is carried out in reverse rotation or gas cutting of high strength bolts, and evaluate about cutting effectiveness and quality of these members. Our verification also indicates that the result applies to actual low-storied steel structures.

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