A conducive acoustical environment for children is considered essential to support healthy growth. However, the significance of acoustical quality in nursery facilities has not been fully recognized in building design. Further, the management and types of nursery schools are now diversifying and various acoustic disturbances such as excessive noise in the environment or reverberation are often noticed. At present, the architectural Institute of Japan (AIJ) indicates the guidelines for acoustical properties of schoolrooms for elementary schools, as well as junior and senior high schools. AIJ is also working to extend the guideline for schoolrooms to nursery facilities and preschools. Against this background, the study conducted a field survey across twelve nursery facilities to assess the status of acoustical environment.
 The survey observed the division of spaces for each age, the dimensions of and finish on surfaces in rooms, and children's activities conducted within them. Additional information was collected on the background and characteristics of each facility, the users' evaluation of facilities, and evaluation of the acoustical environment in nursery rooms. Noise levels and reverberation time were measured in four facilities, and a management system to maintain a comfortable sound environment was observed in one facility.
 The survey on the division of spaces for each age group indicated that in most facilities, the nursery rooms were designed with poor acoustical separation. A typical case of successive nursery spaces was observed in a rented room in a part of the building. Here, the successive spaces were divided by low shelfs or fences, and groups of different ages engaging in different activities shared the sound environment. Additionally, some nurseries were characterized by mixed-age grouping activities and spaces were set not by ages but by activities. Movable partitions and sliding doors were installed to ensure flexible use of spaces according to the activities. Connectivity between spaces was found to facilitate cooperation, but was detrimental to the sound environment. As observed in the survey, such “mono-spaces”—connected rooms without sufficient sound insulation—may cause acoustical problems. As some teachers mentioned during their interviews, there were instances of acoustical disturbance due to voices from other groups.
 The survey found sound-absorptive materials in use in only a few of the facilities visited. Long reverberation times were measured in nursery rooms without absorptive materials, especially those with a high ceiling and those organized as successive spaces. Another typical problem was noise exposure attributable to the ventilation system and site location such as underneath elevated railway tracks. In nursery facilities, the effects of noise should be considered not only in the context of speech communication, but also in the context of sleep disturbance during naptime.
 It was observed that a management method to maintain a comfortable sound environment was important. In one nursery facility, nurses pursue the concept of “break away from the noise” and participate in a training session every year. The facility also inculcates practices of gentle vocal communication, and measurements showed lower levels of sound generation during activities.
 The results of this study indicate considerable differences between the acoustical environments in nursery facilities and school buildings. It is hoped that the findings of this study will be taken into consideration while formulating guidelines for acoustical environments in nursery facilities. It is also necessary to diversify the method to improve acoustical environment through additional absorptive treatment and effective management to maintain a comfortable sound environment.

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 The construction machineriy noises have a sound peak in low frequency region(approximately less than 100 Hz). Active noise control (in the following, ANC) is one of the methods to reduce the low frequency noise. ANC is a system that reduce noises by interference between noise and sound wave from a speaker that has reverse phase against the noise. In recent years, ANC is occasionally applied to reduce noise of construction machineries like backhoes and rough terrain cranes.
 As usual, the control method of the ANC is feedback that has only error microphone, or feedforward that has the reference microphone and the error microphone. In the construction sites, there are many kinds of noise sources like backhoes, cranes, power generator, roadheader, etc., therefore the ANC using feedback control may lose the target noise. Also, most of construction machineries move around in the construction site during operation, for safety it is hard to set up two microphones on the machineries for feedforward control.
 So we developed an active noise control system for noise of construction machineries that can be set up on moving noise source like backhoes and can control stably. We considered about the applicability of the feedforward control which uses only reference signal, uses no Ĉ. Then, we proposed control methods of the ANC which estimate a predominant frequency and calibrate an amplitude ratio and a phase delay in time domain.
 To estimmate a dominant frequancy in time domain, the proposed control method uses the optimized filter of LMS algorism. The LMS algorism minimizes the difference of input signal and the band-pass- filtered signal in the ANC system. The coefficient of the optimized filter is updated by each sampling time, the estimated frequency at n+1(n means a time number. n=1, 2...) is mainly derived from the estimated freqency at n, and the ratio of the coefficient of the optimized filter at n+1 to the coefficient of the optimized filter at n.
 As for the calibration of an amplitude ratio and a phase delay in time domain, the proposed control method uses correction values of amplitude and phase delay in each frequency, which are obtained in advance from the comparison o of the input signal and the output signal of the ANC system. When the control starts, at first, the system takes out the correction value of the estimated frequency. Next, the system subtracts the number of data of the correction value from the number of data of one wavelength for the estimated frequency. At last, the system takes out the past data at the point of calculated difference from the start point, and the data multiply by the correction value of amplitude is the output signal.
 To confirm the usefulness of the proposed method, we carried out numerical simulations. In the simulation, we used some fixed sin waves of 50Hz to 100Hz, and fluctuated sin waves such as 40Hz to 50Hz or 40Hz to 100Hz, as input signal. As a result, the proposed methods can control stably and the control speed of proposed method is faster than that of conventional feedforward control and conventional feedback control.
 Then, we carried out experiments in a laboratory to verify the effectiveness of ANC system using proposed method. Some fixed sin waves of 50Hz to 100Hz and construction machinery noises are used as input signal. As a result, the ANC reduced fixed sine waves by maximum about 20dB, and the ANC reduced construction machinery noise by about 10dB.

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 Floor vibration is an important factor in living conditions. Recently cases to need countermeasures for floor vibration reduction increase because building life becomes long, and the criteria of vibration may sift by replacement of residents or the exposure force may be large by change of neighboring traffic. In this research, influences that prior experience of floor vibration gives for the judgments of allowance for reduced vibrations was examined in sensory evaluation test. By the examination, it was shown that reduced vibrations may be allowed by being reduced at fixed ratio, no matter the vibrations are larger than individual absolute acceptable limit of examinees. And the unevenness of reduction ratio for allowance caused by individual difference is smaller than the unevenness of the absolute acceptable limit of examinees.

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 The CIE mesopic photometry system (CIE, 2010) was based on target detection performances at an eccentricity angle of 10 degrees. It has not been confirmed whether the MES2 system can be applied to other eccentricity angles in the peripheral visual field. To verify the validity of the CIE mesopic photometry system and modify the system if necessary, this study conducted a target detection experiment by employing six subjects. This experiment measured the subjects' reaction times for targets presented at eccentricity angles of 5, 10, 15, and 25 degrees from the center of the visual field. This experiment used light levels between 0.005 cd/m² and 2 cd/m² and two lamp spectral power distributions of yellow LED (S/P ratio=0.10) and white LED (S/P ratio = 1.86). Based on the results of the experiment, this study found that the visual field within 5 degrees from the center of the visual field can be treated as the central visual field where only cones function even under mesopic light levels. The CIE mesopic photometry showed good correlations between mesopic luminances and reaction times for the two SPD conditions at eccentricity angles of 10 and 15 degrees. However, the luminance borderline between the photopic vision and the mesopic vision at the eccentricity angle of 25 degrees seemed to be higher than 5 cd/m², which the CIE MES2 defined.
 Therefore, this study attempted to modify the mesopic luminance formula only for the eccentricity angle of 25 degrees.

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 In this study, the authors have sought under laboratory conditions to evaluate visually challenged subjects and their preferred level of brightness using three categories: those which are i) barely visible ii) easily visible iii) too bright to be visible.
 On the visual targets, four types of achromatic-color lines at 7.5 cm in width were placed one by one on A4-size backgrounds of different achromatic colors; these were designate N9 and N3. The lines were combined with the backgrounds in a total of seven ways to create a combination of luminance contrasts. These visual targets were displayed on a vertical wall facing the experimental apparatus at a visual distance of 1m.
 The subjects evaluated each illuminance value with three types of criteria: barely visible, easily visible and too bright to be visible. As a result of this research, the authors determined that the relationship between illuminance and contrast for visually challenged people, is as follows;
 (1) The result of illuminance was not affected of visual acuity and impact of eye disease of visually challenged subjects.
 (2) The illuminance of visually challenged subjects varied in individuals and was larger than the young. Also, the data of "barely visible" evaluation in increasing in brightness was higher than decreasing.
 (3) A percentage of 28 to 35 of visually challenged subjects evaluated "too bright to be visible" under 1000lx.
 (4) The ratio illuminance of "easily visible" in the background N9 was 29 to 120 times higher than "barely visible" in increasing in brightness, and the ratio illuminance of "easily visible" was 12 to 62 times higher than "barely visible" in decreasing in brightness. The ratio of "easily visible" in the background N3 was 46 to 90 times higher than "barely visible" in increasing in brightness, and the ratio illuminance of "easily visible" than "barely visible" was 24 to 42 times in decreasing in brightness. Therefore, these numbers of ratio in decreasing in brightness were about a half of the increasing conditions.
 (5) The illuminance of "easy visible" of visually challenged subjects was 0.6 to 1.7 times higher than that of the young subjects, and the illuminance of "barely visible" of visually challenged subjects was 15 to 82 times higher than that of the young subjects.
 (6) The authors showed the percentile values of the illuminances of visually challenged subjects.
 (7) Using the percentile values of illuminance, the authors showed the figures and the regression equation by the relationship between the illuminance and luminance contrast of "proper illuminance range" and "optimum illuminance range".
 (8) The comparison of the illuminances in positive and reverse contrasts, it was reversed at the specific conditions.

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 Studies have previously been undertaken on the prediction of perceived spatial brightness aimed at achieving designs that take account of a feeling of brightness of space, and various estimation models and factors affecting the prediction of perceived spatial brightness are known. In this study the authors focused their attention primarily on factors other than average brightness to explain perceived spatial brightness in nonuniform luminance distribution with the aim of proposing an index which encompasses existing knowledge while being based on simple quantities.
 The authors set 32 different lighting conditions in an office with north-facing windows and measured the luminance images for each condition. They then asked subjects to evaluate the perceived brightness from two seats, one with the windows in sight and with no windows in sight, thereby providing 64 different luminance distribution and estimation value samples. Ten contrast images of different spatial frequency were decomposed from each luminance image by wavelet transformation symlet6, then AD (ambient directivity, low spatial frequency) and CD (contrast detail, high spatial frequency) were defined on the basis of each variance of contrast image.
 The authors used multiple regression analysis to obtain a multiple regression equation to explain spatial brightness using three variables: average luminance, or NB value; AD; and CD. AD lowers spatial brightness, while CD raises it. The estimated accuracy was greater than that achieved using a conventional equation.
 After considering the above, the authors suggested NSB (Natural scale of Spatial Brightness), a spatial brightness prediction model based on luminance contrast.

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 Focusing on areas of traditional architecture and historical importance in China and Japan, this paper is an investigation of the relationship between color and the extent to which the space of advertising fascia can be used for advertising before being perceived as too disruptive to the design of the building and the local ambience. Based on the Munsell color system, a survey was conducted, using questionnaires, to collate responses to different uses of hue, value and chroma combined with varying degrees of fascia coverage. The results showed that: 1) in cases when less than ten percent of fascia of individual buildings was used for advertising, changes in hue, value and chroma had a greater influence on the perceived visual impact of the area as a whole, compared to when changes were made to the amount of the fascia covered with advertising. 2) with chromatic color, changing the values had a stronger effect on people's perceptions than when changing the values of achromatic colors. 3) for chromatic color, when the fascia area used was < 3%, value < 3 and chroma < 6, similar levels of hue R, Y and B were considered to be acceptable, and higher than for hues G and P. 4) questionnaire respondents were more tolerant of increased areas of hue Y when used on Japanese wooden architecture.

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 Since solar radiation has big impact on roofs of the building, the control of solar radiation on roofs is one of the most important subjects in improvement of the indoor thermal environment of residential buildings. Up to now, attic ventilation, insulation, heat insulation coating, roof sprinkler, roof planting, etc. have been studied about the control of solar radiation on roofs. However, the research on the influence which roof shape, roof pitch and roof azimuth give on the heat environment of a building hardly exists. This is a very big problem in residential buildings of Japan which has to consider the climatic change of the four seasons, the typhoon or snow.
 The purpose of this study is to show the roof design guideline of the residential building where environment is considered by clarifying quantitatively relation between the roof form and attic temperature.
 Long-term observations of attic temperature were performed using the model of various roof forms. Compared with the shed roof, attic temperature of the gabled roof was high, and the influence of roof azimuth was small. When the pitch of roof was small, attic temperature was high, and the differences of the attic temperature accompanying various roof forms were more than 4 °C in the summer, and more than 2 °C in the winter.
 Using the algorithm of natural room air temperature, attic temperatures were estimated and the accuracy was verified. The attic temperature that was estimated from weather data matched with the actual experiment data with roof model, and the correlation coefficient of estimated data and measured data was 0.97 or more.
 Based on the Expanded AMeDAS Weather Data of 13 points in Japan, the influence which various roof forms give to attic temperature was investigated. The results of simulation are as follows:
 1) The difference of the attic temperature according to roof forms reaches to 15-25 °C in summer and 5-10 °C in winter.
 2) Difference among regions of the attic temperature with the roof form is affected by solar radiation and wind velocity.
 3) The attic temperature is high at hip roofs or gable roofs in summer, and it is high at shed roofs in winter.
 4) The attic temperature of the roof of a steep slope is low, and the tendency is stronger in summer than winter.
 5) Gable roofs and hip roofs have the low dependence to the roof azimuth, and shed roofs are dependent on the roof azimuth, only when a pitch of roof is large.

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 Tsuchikabe (wall made of a mixture of soil, water, sand, and straw) made of natural materials does not induce sick building syndrome. While being built, tsuchikabe requires no VOC-containing materials. A building with tsuchikabe produces fewer CO₂ emissions. It therefore holds promise for reducing LCC (CO₂). Buildings with tsuchikabe, however, are on the decrease because of the long work period and high labor costs. The authors intend to verify whether the indoor environmental control performance of the tsuchikabe, which uses natural materials, is worth its building price. To begin with, the thermal insulation performance of the tsuchikabe (composite material) built by a plasterer using traditional skills was measured as reported in this paper.
 Two types of specimens were used: one measuring 900 mm on each side that allows measurement of equivalent thermal conductivity with the calibrated hot box method (JIS A1420 Annex B) (hereinafter Specimen A) and the other measuring 300 mm on each side that allows measurement of direct thermal conductivity with the heat flow meter method (JIS A1412-2) (hereinafter Specimen B). Specimen A has the same shape and size as the actual material. Specimen A was prepared over a foundation of two nogs, six bamboo laths, and 28 wattles, with plasterers applying a covering of ara tsuchi (a mixture of paddy field earth, rice straw and water) (55 mm in thickness) and a browning coat of nakanuri tsuchi (mixture of river sand, mountain earth, water and rice straw) (both sides: 10 mm in thickness). Specimen B was prepared over a foundation of 12 wattles and a browning coat of nakanuri tsuchi (60 mm in thickness). As it turned out in our case, the interval of wattles used in the specimens ranged from 22 to 24 mm. This spacing is smaller than that of the standard building procedure.
 The authors confirmed the occurrence of dry shrinkage of tsuchikabe as reported in this paper. The volumetric shrinkage (average) under the steady state (air dry condition) is 4.7% for Specimen A and 5.5% for Specimen B. Plasterers generally estimate dry shrinkage of tsuchikabe prior to building one. The equivalent thermal conductivity of Specimen A as a composite material was 0.392 W/m·K. The thermal conductivity of Specimen B was 0.344 W/m·K. The equivalent thermal conductivity of Specimen A was estimated using the thermal conductivity of a single material (wattle, earth, and nog (cedar)). The thermal conductivity of the wattle part (wattles and earth) is 0.394 W/m·K, and the thermal conductivity of the nog part (wattles, earth and nogs) is 0.336 W/m·K. The authors consider the difference between both measurement values is attributable to nogs. Assuming the wattle part and the nog part conduct heat in parallel, the apparent thermal conductivity of the composite material can explain the measurement value at a sufficient accuracy.
 The thermophysical property of tsuchikabe built by a plasterer was measured as reported in this paper. The thermal insulation performance of the tsuchikabe is no larger than that of other building materials when compared in terms of equivalent thermal conductivity. However, analysis confirmed that sufficient thermal insulation performance is duly expected to occur because of tsuchikabe's thermal capacity. When evaluation of the humidity adjusting performance of the wall progresses, it will be able to evaluate the indoor environmental control performance and the validity of the construction price.

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 The purpose of this study is to quantitatively evaluate the effectiveness of the components of existing PVC windows in the country in providing thermal insulation, to identify the optimal conditions of the components and the insulation performance of windows with the components in the optimal conditions, and to conduct a performance test on samples under the practical specifications for production. We briefly summarize the results below.
 1) For the frame, using a method of quality engineering, we examined the reduction in conductive heat flow across each cross-section for multiple regulatory elements, which would contribute to thermal insulation. We then derived the optimal condition (level) for each regulatory element and showed the reduction rate under the optimal condition (sash frame part 19%-21%, fix frame part 6%-10%, mullion frame part 22%). Furthermore, based on the SN ratio, we found that the reduction rate is highest with the following components: inner-frame insulator in the sash frame part and fix frame part, and physical properties of mullion reinforcement in the mullion frame part.
 2) As for the glazing part, we examined the specifications of the Low-E film suspended air space of a insulated glass and observed the effect of a Low-E film, optimized the arrangement, and the optimal thickness of the air space for each gas fill. We also examined the thermal transmittance at the center of glass with xenon gas having 3 films (0.29 [W/(m²·K)]), and those at the center of glass with krypton gas having 2 films (0.39 [W/(m²·K)]).
 3) We determined the thermal transmittance of the window (0.56 [W/(m²·K)]) with the combined optimal conditions for the frame and glazing parts. In actual manufacturing, however, there are two problems: a technical problem (of forming a metal film inside the frame cross-section and arranging phenolic foam insulator without leaving any space) and a high manufacturing cost (associated with filling xenon gas inside the insulated glass). We therefore examined the insulation performance of samples having practical specifications for production. As a result, we obtained a measured thermal transmittance of 0.63 [W/(m²·K)] in contrast to the calculated value of 0.65 [W/(m²·K)].

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 This paper presents a thermal load simulation method for spaces conditioned by heating, cooling and fresh air control systems combined with natural ventilation. Fresh air control systems enables free cooling, demand control ventilation and energy recovery ventilation. Natural ventilation may be carried out while spaces are conditioned by cooling equipment.
 For simulation of natural ventilation, many conditions which must be satisfied for natural ventilation can be considered and the under limit of space air temperature is supposed to be controlled by regulating ventilation opening area. On the other hand, natural ventilation rate is calculated under the simple conditions where airflow balance is not solved and the location of the neutral zone is assumed to be fixed. Space air temperature control by free cooling and heat recovery ventilation can be simulated. In demand control ventilation, ventilation rate is estimated in proportion of occupancy rate
 For heat balance simulation of multi zones where fresh air control systems combined with natural ventilation are used, a new method was developed in order to enable speedy simulation and to avoid complicated procedure. In the proposed method for iterative solution of heat balance and fresh air rate which means sum of natural ventilation rate and forced ventilation rate for free cooling, space air temperature control by regulating fresh air rate is replaced for control by a virtual heater and cooling and heating capacities are intentionally increased. This procedure suppresses iteration of calculating fresh air rate and the solution such as heating rate, cooling rate and fresh air rate can be obtained by correcting the calculated results.
 The proposed simulation method was applied to the building simulation engine in BEST which is a whole building energy and thermal load simulation program and the simulations for a typical office building located in Tokyo were performed. The basic effects of fresh air control techniques and natural ventilation on space thermal environment and thermal load were presented.
 The interaction effects of energy saving strategies such as high performance building facades, natural ventilation and fresh air control techniques were evaluated through simulations in two buildings. One is a low-performance building and the other is a high-performance building. The energy saving rate for a low-performance building is defined as the thermal load reduction achieved by adding an energy saving strategy, and that for a high-performance building is defined as the thermal load increase resulted by removing the strategy employed in the high-performance building. Although some strategies provide lower energy savings for the high-performance building than for the low-performance building, a few strategies are more effective for the high-performance building.

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