The number of cold-formed steel framed houses is increasing and they tend to be built as apartment houses rather than detached houses. Along with this trend, heavy-floor impact sound insulation performance of the houses is expected to be improved. In order to meet this expectation, experimental test and numerical analysis are carried out, using the really-constructed houses as specimens. The results indicate, 1) in order to improve the heavy-floor impact sound insulation performance of cold-formed steel framed houses, sound pressure in a frequency band of 63 Hz has to be reduced, 2) floors of cold-formed steel houses tend to vibrate in a perpendicular direction to floor joists axis in the low-ranged frequency band, which is caused by the anisotropy of floor bending stiffness, 3) considering the vibrating mode shape, to improve sound insulation performance, it seems one of the solutions to increase the floor bending stiffness of weak axis, and 4) the possibility of the suggested solution is confirmed through the on-site test.

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 It is effective for power-saving of office lighting to set working plane illuminance lower than usual, but without consideration of room appearance this tends to lead to gloomy impression. To avoid this negative effect, some methods to predict brightness impression are used for office lighting design, but they have not been well examined from the view point of applicability to office lighting. It is apparent that the average luminance of office perspective image is important but the value changes in accordance of view range. This study, as a basic research, examined appropriate vertical range for prediction of perceived spatial brightness.
 The authors set 48 different luminance distribution conditions in a 1/6 scale model of office environment, and asked the subjects to evaluate spatial brightness with magnitude estimation technique. The luminance distribution from the subjects' evaluation point was measured by a digital camera with 180 degree fish-eye lens and average luminance was examined.
 As the result, the authors obtained followings;
 1) When sitting on a desk seat, spatial brightness can be predicted by mean luminance ranging from 0 to 20 degrees on the luminance image in vertical, with exclusion of objects just around the desk like partitions, but in the case of short room depth or including windows, the mean should be ranging from 0 to 40 degrees.
 2) Vertical range to average luminance for prediction of spatial brightness should be adjusted in accordance with characteristics of the room examined.

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 Thermal environment around each occupant changes in different ways, because thermal distribution in a room changes at every hour. To evaluate indoor thermal environment, usually CFD simulation in a certain time is done. However, this evaluation is insufficient, because time change of thermal distribution cannot be considered. It is preferable that every occupant is comfortable at more than a certain rate of time. Based on this idea, an air-conditioning system which can removing internal heat gain within the vicinity of the heat source, was developed to minimize the thermal distribution of occupied zone. Thus the purpose of this study is to evaluate the thermal environment in occupied zone of this system considering space distribution and time change. In this study, PMV values of all occupants over the cooling period were calculated, and the comfortability rates of occupants by this system were compared with those by conventional system. By using the calculation result of PMV, time, point and factor of the case that comfortability is not satisfied in the cooling period. By this system, the differences of PMV value were smaller and the comfortability rates were higher than that by conventional system. In contrast, by conventional system, the comfortability rates were different even among occupants close to each other. A calculation method is proposed to calculate PMV values of multiple occupants over a period, and accuracy verification is done by means of comparing with CFD analysis.

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 The purpose of this study is to establish the evaluation and measurement methods of the odor of new constructed houses based on the electronic nose analysis.
 In recent years, the number of complaints against the nasty smell in new constructed houses has been increased. But the evaluation and measurement methods for the perceived air quality in the new constructed houses have not been established. The previous studies concerned with the perceived air quality in the new constructed houses are intended to identify the appropriate finishing materials that may not emit a powerful smell. The measurement and evaluation methods for the odors emitted from finishing materials in the previous studies are mostly based on the sniffing tests by the subject. While the measurement of the odor intensity based on the triangular odor bag method is relatively simple, the specification of odor characters needs the complicated process. For example, ISO have many standards of ISO 5496” Initiation and training of assessors in the detection and recognition of odours”, ISO 8586” General guidelines for the selection, training and monitoring of selected assessors and expert sensory assessors” and ISO 11035” Identification and selection of descriptors for establishing a sensory profile by a multidimensional approach” and et.al. for the sensory analysis to specify the odor characters.
 In this paper, the electronic nose is adopted to measure the odors emitted from finishing materials. This analyzer has the technique of odor similarity mapping represented in the radar chart in order to make clear the odor characters. The specification of odor characters obtained by the electronic nose is comparatively easy as compared to the sensory analysis.
 In the first stage of this study, a field research for the perceived air quality in the new constructed houses was carried out. The nasty smell in the new constructed 12 dwellings of 8 detached houses, 4 units of the newly-built two apartments were analyzed by the electronic nose. The odors diffused from the floor components, the wall components and the ceiling components comprised with multiple finishing materials such as a structural plywood, an adhesive, a composite flooring, a gypsum plaster board and a vinyl wall paper are focused.
 The following results were obtained. (1)The perceived air quality among the new constructed houses with the same material and the components specifications for interior finishes is similar. (2) The main source of the nasty smell in new constructed houses is suggested to be the odors dissipated from interior finishing materials.
 The small chamber tests for the similarity level among the odors emitted from the floor components, the wall components, the ceiling components and the nasty smell in new constructed houses of the field survey were conducted. The similarity between the actual odors in the new constructed houses and the odors emitted from the floor components is high, but the other odors dissipated from the wall components, the ceiling components, the adhesive, the composite flooring and the gypsum plaster board have low similarity to the actual odors.
 Model experiments may be necessary to elucidate the odor pollution mechanism. As the first step, the odor in a test chamber set in the same floor component, wall component and ceiling component as actual one was confirmed the reproducibility of the perceived air quality in the new constructed houses.

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 Energy conservation technology has been in high demand in relation to efforts to realize (net) zero-energy buildings (ZEBs). Ceiling radiant cooling panel systems represent a key energy-conservation technology which can yield high efficiency, since it uses moderately cold water (16－18°C), offers integration with other energy-efficient strategies, such as indirect evaporative cooling or ground source heat pumps, and does not require energy to propel a fan to remove the cooling load. Furthermore, a radiant ceiling cooling panel system provides greater comfort to occupants because it does not produce a draught. Therefore, ceiling radiant cooling panel systems can offer both reductions in cooling energy consumption and a comfortable environment for occupants.
 However, there are several problems with applying a ceiling radiant cooling system in Japan. Firstly, there is limited data about the cooling performance of such systems because few have been constructed in Japan. For this reason, it is important to determine the cooling performance of radiant ceiling panels. Secondly, radiant ceiling panels have limited cooling performance, so it is necessary to consider a special system to remove the perimeter load. Thirdly, an outdoor air-conditioning system is needed to provide outdoor air to occupants. The objective of this paper is to present an outline of the proposed system, results of the thermal performance tests in an experimental facility, and the operational performance in a building to which the proposed system is applied.
 The proposed system consists of ceiling radiant cooling panels, perimeter chilled beams, and an outdoor-air supply system. The ceiling radiant cooling panels remove the interior cooling load. The perimeter chilled beams remove the perimeter cooling load. The outdoor-air supply system has a personal floor diffuser, a perimeter linear diffuser and a return-air inlet near the window top. The return-air inlet removes the hot air from the window to remove the perimeter load efficiently.
 An experimental facility for the proposed system was constructed, and thermal performance tests were performed. The results show a vertical temperature differential of less than 0.5°C, and the perimeter chilled beam can remove the peak summer cooling load appropriately. The cooling capacity of the ceiling radiant cooling panels and perimeter chilled beams are approximately 80 W/m² and 120 W/m² respectively under conditions whereby the difference in temperature between the water input and output is 9.0°C.
 Measurement of the system was performed in the actual building to which the system was applied. The results show that the ceiling radiant cooling panels and chilled beams can be controlled to remove varying cooling loads. The cooling capacity of the ceiling radiant cooling panels and chilled beams in the actual building proved almost equal to the experimental data. Thus, it is demonstrated that the proposed system can remove the cooling load as expected.

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 The energy consumption in the commercial buildings sector has been still increasing in Japan. Especially, that for cooling and heating demands accounts for about 30%. In exciting buildings, which have an overwhelming proportion in the construction market, there is the possibility that the cooling / heating load is different as that at the point of design of the air conditioning system. Commissioning, which is a process to analyze the performance, find problems and apply adjustments, is an effective solution for operation improvement in such buildings.
 We have investigated the effect of operation improvement through commissioning for a central heat source system installed in a hospital facility which has the total floor area of 13,364 m² and 100 beds for in-patients. Possibilities for further energy saving were discussed based on the analysis of the seasonal variations of cooling / heating load and the system performance using the BEMS data. Several kinds of operation changes were examined by computer simulation using the Life Cycle Energy Management (LCEM) tool. We further demonstrated the effect quantitatively by applying the operation changes in the facility and also discussed the differences between the calculation and measurement.
 The heat source system had two units of gas-driven absorption type chiller-heaters (ABS) and two units of electricity-driven air source heat pump chillers (ASHP) with ice storage function, where each capacity for cooling was 633 kW and 206 kW at the rated condition. The annual primary energy consumption was 2,153 MJ per the total floor area, which was about 14% smaller than the value from the DECC database. This is probably due to few surgical operations that consume a large amount of energy for sterilization and air conditioning. About half of the total energy was used for air-conditioning, in which two third of that was in the form of electricity.
 At the original operation during cooling, chilled ice was stored in the one or two units of ice storage in the nighttime; the cold energy was used for cooling in the daytime. The rest of the cooling load was covered by the ABSs. We found that the heat sources produced too much cold energy compared to the cooling load throughout the season. The ice storage operation also resulted in a relatively lower thermal efficiency, which was a ratio of the energy consumption to the covered cooling load, than the ASHP without storage or the ABS. We therefore proposed decrease of number of the operated heat sources and non-storage operations. Simulations by the LCEM suggest that the maximum load can be covered by the one ABS, and the ASHPs lead to energy reduction in the low load period. As the result of the operation changes in the facility, we finally obtained energy reductions of 29 % in June and 18% in July in 2014.
 In the heating season, the ABSs were originally operated throughout the season. The produced heat usually reached 1.8 times as large as the heating load. This is due to the large capacities of the ABSs compared to those of the ASHPs. We therefore proposed to adjust the produced heat by use of the ASHPs also for heating. The operation change provided an energy reduction of 25% in 2014 whereas the LCEM simulations predicted an effect of 40% in maximum. The difference seems to be due to a problem in the actual piping, where produced heat once passes through the storage tank even in the non-storage mode.
 We conclude that a certain amount of energy reduction can be obtained by commissioning for the heat source system in both the cooling and heating seasons.

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 Many experiments and numerical simulations have been conducted for decades to investigate the relationship between urban flow characteristics and urban geometries (e.g. Kubota et al. J. Environ. Eng., AIJ. vol. 43, 2008).
 Meanwhile, most of the studies in the past assumed the real urban geometry as idealized block arrays; however, real urban surfaces generally include diverse and complicated topographies derived from balconies and penthouses. A few pioneering studies investigated the impact of complex surface topographies on flow fields. For example, Reynolds-averaged Navier-Stokes (RANS) simulation for 2D street canyon with flat eaves carried out by Mohamad et al. (Building and Environment vol. 44, 2008) presented the drastic effects of eaves on temporally averaged flow fields around building models. With this curious investigative result, the authors have conducted a wind tunnel experiment with a time-resolved particle image velocimetry (TR-PIV) system for further investigation about the nature of turbulent flows around 2D street canyons with flat eaves.
 In this study, 2D street canyons of four different shapes were employed. A canyon aspect ratio (ratio of the street width to canyon roof height) of 3 and 7 for canyons with eaves and without eaves are used. The images of turbulent flow fields were photographed at a frequency of 1, 000 Hz and a camera magnification of 0.17 mm/pixel. A direct cross-correlation algorithm is employed for image analysis with the combination of a recursive cross-correlation method and an image transforming method (window deformation iterative multigrid, WIDIM). An appropriate setting for the size of an interrogation window is important in the WIDIM method for improving the data accuracy and spatial resolution. Thus, the authors optimized the size of the interrogation window size based on the histograms of the particle displacement rate so that peak locking problems do not arise. In this study, the following four results are obtained.
 In a narrow canyon, the vector maps of temporally averaged flow fields indicate that the flow regime inside the canyon was drastically changed by eaves causing a complicated flow field, which contains three vortexes of similar sizes. In contrast, in a wide canyon, the flow regimes of the canyons with eaves have a few points in common around the center with that of the canyons without eaves. However, eddies appear under the upward and downward eaves causing a change in local flow field structures.
 The standard deviations of streamwise and vertical turbulent components and the Reynolds stress become small inside a narrow canyon with eaves. However, they become slightly large in the area where the high-speed downward flow directly reaches from above the canyon. In contrast, in a wide canyon with eaves, the standard deviations and Reynolds stress become small in the upstream region while the maximum peaks appear in the downstream region.
 The canyon ventilation rate of a narrow canyon with eaves is only 11% when compared to that of a narrow canyon without eaves, whereas, the ventilation rate is maintained at 70% in a wide canyon with eaves. Judging from the 2 point correlation function of the vertical velocity component, in a narrow canyon with eaves, the penetration of a large-scale turbulent structure into the canyon is prevented by the eaves reducing the vertical air mixing. In contrast, in a wide canyon, the impact of eaves on the large-scale turbulent motion is small; thus, the air exchange rate is maintained.
 Large-scale upward and downward turbulent motions cause air mixing in the spanwise direction in canyon. The intensity of spanwise air mixing with a large turbulent motion is close to the canyon ventilation in the narrow canyons; however, it is weaker than vertical air mixing in the wide canyons.

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 In recent years, the population of Japan has experienced an increase in allergy-type ailments such as asthma and other forms of respiratory distress, particularly among members of the younger generation. There are several reasons behind this upsurge in allergy-type diseases, and it is deemed likely that indoor dampness provides some of the strongest contributory factors. In order to clarify the association between child allergic diseases and indoor dampness, a cross-sectional survey has been conducted to 4 - 12 years old children through the internet survey. Questionnaires were distributed on the web to the 6, 618 houses in all prefectures of Japan on February of 2013, and the 5,071 completed questionnaires were sent in five days. The response rate was 76.6%.
 This paper firstly described the estimation method of indoor dampness using the results of occupants' self-reported answer to questions about visible vapor condensation, visible mould growth, perception of mouldy odor and so on during winter season. This dampness index proposed in this paper was calculated as the value from 0 to 24 points and its values classified into four kind of rank on the basis of the quartile. Rank 4 presented the house which had the most serious problems related to indoor dampness. The dampness index revealed the association between indoor dampness and allergic disease such as asthma and rhinitis.
 Secondly, from the questionnaire the prevalence of current asthma on the basis of diagnosis of a doctor was around 8.0% among children. The prevalence of allergic rhinitis was increasing as they grew up and it was 20.5% among 10 - 12 years old boys. This tendency was seen in the prevalence of hay fever and allergic conjunctivitis. In general, boys had higher prevalence of allergic disease than girls. On the other hand, the prevalence of chemical sensitivity and SHS(Sich House Syndrome) are much less than that of allergic disease, and these symptoms were less than 1%.
 Finally, the association between adverse health effect and influencing factors related to indoor dampness was discussed. Adjusted Odds Ratios(hereinafter referred to as ORs) was calculated using a multivariable logistic regression model adjusted for gender, age, location of house, a yearly income and so on. Adjusted ORs of current asthma (OR = 1.46 and 1.81, p < 0.001) was statistically significant in both rank 3 and rank 4 of the dampness index. In this analyzed results, the increased risk of asthma due to indoor dampness was estimated (p for trend <0.01). In addition, adjusted ORs allergic rhinitis in from rank 2 to 4 was statistically significant in higher rank of the dampness index. The dose-response relationships between indoor dampness and both current asthma and allergic rhinitis were presented using the dampness index proposed in this paper. Analyzed results revealed that the operation of a mechanical ventilation (p for trend < 0.05) and living near arterial roads (p < 0.05) were associated with current asthma. The living near industrial factory (p < 0.01) and river (p < 0.01) were associated with allergic rhinitis, as well. We could conclude that children who were living in dampness are at significant risk for allergic diseases such as asthma and rhinitis.

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 Through the analysis of the design method of Kenzo Tange Laboratory, the University of Tokyo, and the theory as its background, this study has clarified how the clear system in the urban design of Tange Laboratory has been adopted to the computer simulation and examined the significance of the method in the present context. After organizing the cases where computer is used in the early stage of Japanese architecture field, the study has clarified that the use of computer by Tange Laboratory had uniqueness in the point that the target of such use was the urban area. The study showed that this viewpoint of the use of computer by Tange Laboratory was related to the leading study in the United States at that time that was conducted by K. Lynch and C. Alexander, and discussed about its characteristics.
 The study indicated that the computer simulation method of Tange Laboratory could be broadly classified into the one of macro type that treats the whole nation and the one of micro type that treats human spatial cognition. The simulation of macro type is related to the simulation method of social sciences at that time, such as system dynamics or discrete simulation, which was distinctive in the point that such simulation intended to introduce the viewpoints of social sciences in addition to the rationality of civil engineering. The simulation of micro type is related to urban space analysis by K. Lynch, which was outstanding in the point that such simulation was carried out to understand how the elements of scenery image would influence the human spatial cognition, without liMITing to the issues whether the spot is visible or invisible. Through the analysis for the project of Tange Laboratory that was conducted by using these computer simulations, the study clarified that the computer simulation method of Tange Laboratory was the one that was developed from the study on the urban area of Tange Laboratory conducted before the introduction of computer simulation. In addition, it showed that the use of computer by Tange Laboratory has developed on the background of the development of computer technology in the same period of time and maintenance of social information environment, while correlating to urban design projects which had been worked on in parallel.
 The study clarified that the attempt of the introduction work for the use of computer by Tange Laboratory was the one that intend to develop “URTRAN” that has three subroutines as “URBOT”, “RIBOT” and “GRAPHOT”. The characteristics of “Urgorithm”, the concept of the use and development of the computer of Tange Laboratory, was that it focused on feedback circuit and human-machine system. The ideas, which attempt to produce designing plans from more diversified optimization conditions by placing the intervention of the human will on the computer processing, were the significant ones that led to the current use of computer. The study showed that the use of computer by Tange Laboratory and its concept, “Urgorithm”, was also applicable to the current computational design.

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