Following previous research, this study was conducted on the factors of starting illuminance levels and dimming curves to observe the perceptual characteristics resulting from changes in the brightness of office lightings.
 Per experimental conditions, two desks were placed inside the testing room (Area: 12.25 m²), and two people participated in the experiment at the same time. For the lighting, four HF fluorescent lamps (32W, 6700K) were fixed to the ceiling, and the dimness of light was controlled using a dimmer. The level of illuminance in the acclimation room before the experiment and in between sessions was set at 500lx on the surface of the desk.
 The conditions for Experiment 1 involved 12 patterns, with two levels of staring illuminance (500lx and 1, 000lx), two illuminance ratios (0.54 and 0.7), and three rates of changes. The experimental methods used in the prior paper for Experiment 2 were followed precisely for this experiment.
 Therefore, it was found that the perception of the subject was influenced not only by the illuminance ratios and rates of change, but also by the starting illuminance. It was confirmed that a high starting illuminance of 1, 000lx lowered the perceptibility of the subject, even at the same illuminance ratio and rate of change in the room and on the surface of the desk. As for the tolerance experienced with regard to the changing brightness, it was found that tolerance was increased if the starting illuminance was higher, if the illuminance ratio was higher, and if the rate of change was slower.
 The conditions for Experiment 2 consisted 12 patterns, with the starting illuminance at 750lx, two illuminance ratios (0.5 and 0.7), and three types of light dimming curves (convex, concave, and Weber) for the two rates of change.
 Therefore, no definite effect of the dimming curve was confirmed at any of the illuminance ratios. Within the set conditions of the experiment, it was concluded that the dimming curves had little effect on the perception of brightness and that the illuminance ratio and changing time affect the perception of an office worker.
 As for the tolerance to change in brightness, it was found that tolerance increased for patterns where the illuminance ratio was high and changing time was long. In addition, particularly in patterns with long changing times, the range of tolerance of the Weber curve was slightly larger than that of the other dimming curves. Within the set conditions of the experiment, it was found that linear changes were most suitable for lowering the perceptibility. However, by considering factors such as the difference in the testing environment and lighting apparatus compared to those of experiments in prior research and the fact that the dimming curves were not smoothly operated to the nature of the lighting control system, it is necessary to conduct further experiments in future for observing perceptual characteristics.

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 The design method of structural design was modified from specification-based design to performance-based design by an amended Building Standards Law in 2000. Structural engineers need to elicit request information from home owners by conversation and to determine the target performance to be attained for a performance-based design. This study aims to improve the explanation of environmental vibration. We focus on the relationship between words that express a state of vibration and the vibration image evoked by the word. This study is based on the results of two questionnaire surveys (one with 101 respondents and the other with 32 respondents), an experiment conducted on a vibration table (with 32 respondents), and two hearing surveys (one with 7 respondents and the other with 32 respondents).
  We commence the study by investigating the recognition of environmental vibration. The questionnaire results show that many respondents have felt vibration in their house, but a few respondents did not consider it an important issue. The questionnaire results regarding the types of vibration source experienced by the respondents show that vibration sources other than earthquakes (e.g., wind, railway traffic, road traffic, human footfall, etc.) have a probability lower than 0.35. Therefore, when structural engineers explain the environmental vibration expected to occur at home, the home owner has not experienced the types of vibration source in most cases. Structural engineers therefore need to provide an intelligible explanation to ensure the home owner’s understanding of the concept.
  Through hearing surveys on the explanation of vibration experience by respondents, it is found that a vibration image, which is a mental picture that the respondent recalls when she explains her own experience, consists of three elements (①the type of source the vibration originates from, ②the characteristics of the vibration, ③the magnitude of the vibration). Thus, we found that introducing the three elements into explanations of vibration is effective at making the explanation intelligible. We unveil that onomatopoeia is suitable for explaining the three elements because words can be easily connected with past experience of vibration. Furthermore, it is found that several words (“horizontal vibration” ”vertical vibration” “quick” ”long-short” ”big-small” ”like push-up” ”like swing” ) are suitable for explaining vibration too.
  For explaining the three elements that constitute a vibration image, we investigate what physical properties can be expressed through the above words. With regard to ①vibration source, we show that words relating to vibration sources can express the frequency range because frequency range of vibration image from the word is similar that of actually vibration. With regard to ②vibration characteristic, we show that words that express the direction of vibration or frequency, such as “horizontal vibration” and ”vertical vibration,” are known as words expressing vibration direction. In addition, we show that onomatopoeia and terms such as “like push-up” and ”like swing” can express the direction of vibration plainly and easily. Regarding the expressions of frequency, onomatopoeia can express difference of frequency in three levels. With regard to ③magnitude of vibration, we verify that “big-small” can express the magnitude of acceleration. In addition, we show that onomatopoeia can express gradual difference of acceleration.
  We show specific physical quantities such as frequency and acceleration range, which can be explained using onomatopoeic words or phrases (e.g., “gata-gata”, “yura-yura”, and “don” in Japanese), by the results of the experiment on vibration table.
  Although this study presents useful results, structural engineers will need to select and match words and explanations for each individual separately.

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 This paper examined how varying the shape and color combination of the background and text affected subjective perception of advertising fascia for use on traditional buildings. A survey was conducted, using questionnaires, to evaluate reactions to advertising fascia of different shape and color; the results were then collated and analyzed, in order to gauge the acceptability of advertising fascia based on visual attractiveness and the degree of coordination with the surrounding environment. Also, using varying background colors of different Munsell hues, different color combination of background and text color were explored. The results showed that: 1) a significant difference in the acceptance of advertising fascia was found according to age group, and that the visual attractiveness of advertising fascia affected elderly respondents more; 2) in terms of material and shape of the fascia, using wood in unfinished organic forms, or adding a traditional wooden frame was seen to increase the acceptability of advertising fascia; 3) within the surface area permitted for advertising fascia by local ordinance for historical buildings, appropriate changes to the size of the area did not negatively impact the acceptance of advertising fascia; 4) using colors of hue R with low value and low chroma, and achromatic color with a middle value for the background received the best ratings for acceptability.

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 The purpose of this study is to provide data that will help to create a safe stairway system for barriers-free design. This study targets visually challenged people. Within this context, the authors have sought to evaluate the visibility of lateral lines on stairway edges. The experiments were conducted under 20 varying conditions using 10 luminance contrasts of lateral lines and stairways with 2 low illuminance conditions. Participating in were 30 visually challenged subjects and 28 young subjects. These participants evaluated 5 items ; visual recognition of stair edges, visual recognition of steps, ease of descent, visual recognition of lines and overall score. As a result of this research, the authors determined the following:
 1) When the visually challenged subjects paid close attention to the visibility of the lateral lines on edges indicating that these are very important for them.
 2) As the absolute value of the luminance ratio between lateral lines and goings becomes higher, and as the brightness level of goings becomes higher, evaluation of the visibility of the lateral line becomes grater in both 7.5lx and 75lx illuminance conditions.
 3) As the result of examination of the visually challenged subjects, there are differences in relationship between the illness, thus the retinitis pigmentosa subjects put a low value than the other subjects especially in the 7.5lx condition.
 4) The preference rates by the visually challenged subjects are lower than the young subjects. The rates of the negative contrasts are higher than the positive contrasts, especially by the visually challenged subjects.
 5) Under the 75lx condition, the preference rate reaches 50% of the visually challenged subjects as the luminance ratio is more than 2.16 for positive contrast. Additionally, under the 75lx condition, the rate reaches 50% of the retinitis pigmentosa subjects as the luminance ratio is more than 2.65 for positive contrast, and the rate doesn't reach 50% under 7.5lx for positive and reverse contrasts.
 6) The authors clarified the effectiveness of the lateral lines on edges of stairway, and the lines are very helpful to walk stairs for the visually challenged people. Accordingly, the authors clarified the visibility of lateral lines on edges of stairway in quantitatively.

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 It is known that energy use for lighting accounts for about 20% of the total energy use in Japanese typical office buildings. Electrical power saving countermeasures for lighting, such as partial lighting, were taken after the Great East Japan Earthquake and it was indicated that electrical power use for lighting could be substantially reduced. However, the deterioration of the quality of the visual environment of the office workers was concerned at that time. It is required to find a new lighting method that guarantees the quality of the visual environment in addition to reducing electrical power consumption.
 The purpose of this study is to identify the effects of the lighting control system for ambient lighting with personal switch on energy saving and the occupants' visual comfort. Three different types of the switch for ambient lighting were tested in a real office space located in Chuo-ward Tokyo, Japan. Field measurements were conducted twice, before introducing the personal lighting control system (in June 2012) and after introducing that system (in July 2012), one week for each. Electrical power consumption for ambient lighting, operating conditions of the switch for ambient lighting (on/off) were recorded. The occupancy rate of the occupants, horizontal illuminance and vertical illuminance on window were measured. The lighting environment in the office space and the usability of the switch for ambient lighting were evaluated by the occupants.
 The results showed that the electrical power consumption for ambient lighting was reduced by about 44% in the whole measured office space and that lasted for the next half year except for the summer vacation. The subjects were rather satisfied with the lighting environment in their task area even the brightness level on the desk was not so high due to the individual control of the ambient lighting. However, it was also identified that the occupants seldom switched off the ambient lighting during working hours even in the cases when they left their seats. One of the reasons of this was supposed that the occupants felt fear for the effects of their ambient lighting control on the surrounding lighting environment. Especially for the ambient lighting that could be controlled by more than one occupant, it was kept switched on even when those who living in the area where was lit by the lighting were absent.
 In addition, the effect of the number of the occupants who switch on/off the ambient lighting on the frequency of the occupants' control of the ambient lighting was examined. As results, it was identified that the number of the occupants who switch on/off the target ambient lighting should be minimized to promote active individual control of ambient lighting when they left their seats.

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 1. Introduction
 In this paper, we focused on introduction of phase change material(PCM) into a house to secure a cold storage with night natural ventilation. We conducted measurement in order to understand indoor thermal characteristics in a room with night natural ventilation for introducing PCM on the floor of a house to maximize cooling effect. Measurement was mainly conducted for on a room of the full-scale house where it has two openings at floor level. We measured vertical air temperature distribution and inflow wind speed to understand indoor thermal characteristics. And heat flow was also measured on the floor and under the floor to reveal cold storage mechanism.

 2. Categorization
 We categorized measurement results according to weather condition on each day as follows. 1) Day of large air temperature difference between indoor and outdoor(ΔT) with high inflow wind speed, 2) Day of large ΔT with low inflow wind speed, and 3) Day of small ΔT with high inflow wind speed.

 3. Measurement summary on indoor thermal characteristics
 Vertical air temperature distribution of indoor was influenced by inflow wind speed and ΔT. In case that inflow wind speed was lower than 0.1m/s, cold air accumulated along the floor was not mixed with the air at upper area of indoor. In case that inflow wind speed was over 0.1m/s and under 0.3m/s, inlet air mixed with indoor air. At this time, mixing height was determined by ΔT and inflow wind speed. In case that inflow wind speed was over 0.3m/s, indoor air was entirely mixed with outdoor air, thus vertical air temperature distribution tended to be disappeared.

 4. Measurement summary on cold storage
 Cold storage tended to be proportional to ΔT. Cold storage accelerated as the condition of large ΔT and low inflow wind speed because cold air accumulated along the floor was not mixed with upper air of indoor. In case that air temperature near the floor was 2°C lower than phase change temperature of PCM for solidification, latent cold storage begun to progress. Cold storage ratio of latent heat was averagely 70%, and total cold storage tended to change approximate 1.5 times depending on outdoor air temperature.

 5. Conclusion
 Indoor thermal characteristics and cold storage rate were changed by ΔT and inflow wind speed. In some cases, latent cold storage efficiency of PCM on the floor with night natural ventilation was confirmed. In the future, considering the daily life activity of residents, we are going to research passive cooling effect of PCM including the day time. Also, in order to develop a numerical simulation tool for designing a passive cooling house with PCM including a calculation model of vertical air temperature distribution, we will determine the parameter of turbulence diffusion coefficient by CFD simulation.

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 In recent years, Japan and the rest of the world have been aspiring for the development of net zero energy housing (ZEH) to reduce greenhouse gas emissions. Toward that end, it is required that the conditions necessary to achieve ZEH are clarified with regard to electricity generation using a 3-kW photovoltaic (PV) system; because the implementation of PV systems is feasible on popular house types in the crowded Japanese cities. In this study, we examined the actual energy consumption, carbon dioxide emissions, and thermal environment of high thermal performance houses with solar and natural energy utilization systems. Additionally, we compared actual measurement values to the design values of primary energy consumption that is used for the ZEH assessment criterion in Japan. The issues involved in achieving ZEH are also discussed.
 The major findings of this study are as follows:

 ·The examined houses exhibit “nearly ZEH” performance according to Japan's ZEH assessment criterion.
 ·The total energy consumption of the examined houses amounts to approximately 60% of an ordinary house's total energy consumption; purchased energy amounts to approximately 50% of an ordinary house's purchased energy.
 ·The examined houses' reduction rate of CO2 emissions amounts to over 75% reduction. Thus, it was observed that greenhouse gas emissions are greatly reduced.
 ·The energy costs of examined houses are lesser by approximately \223,000 per year (\18,000 per month) compared to the energy costs of ordinary houses. Demonstrating the cost efficiency of energy-efficient housing contributes to the spread of ZEH.
 ·After accounting for domestic use including home appliances, the energy produced from solar power using a PV system with a capacity of approximately 3 kW, results to approximately 63% of energy self-sufficiency. To achieve ZEH (including their home appliances), additional energy-saving measures are required, such as improving thermal insulation, switching to high-efficiency appliances, and residents choosing more energy-efficient life-styles. Additionally, energy producing measures such as solar heating and hot-water systems should also be considered.
 ·Energy self-sufficiency with regard to total energy consumption excluding home appliances was calculated at 94% (or 106%), assuming that the home appliance use accounts for 33% of total energy consumption (or 20.5 GJ per year), which is similar to the design value of primary energy consumption. This means that the examined houses are almost achieved ZEH (excluding their home appliances).
 ·The actual measurement value of total energy consumption for the examined houses is approximately 83% of the primary energy consumption design value. This difference results from the non-consideration of the contribution of solar heating and hot-water system toward the design value. If the calculation method of primary energy consumption considers various additional energy-saving measures, the popularity of energy-saving measures as well as the popularity of ZEH can increase.

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 In recent years, cross-ventilation is actively used in the mid-season and at night and in the early morning in summer as a countermeasure toward global warming. This aims to gain energy-saving effect of buildings' cooling down and thermal environmental improvements by using of cross-ventilation. Lately, some studies calculated energy-saving effects of cross-ventilation.
 In the calculation of cross-ventilation rate, discharge coefficient is known to change with the wind direction as the same as the wind pressure coefficient is. However, most of the studies calculating the energy-saving effects fixed the discharge coefficient. This means that the precision of these results has still room of examination.
 To this problem, the authors offered the local dynamic similarity model based on the dynamic conditions of inflow openings, and successfully calculated the discharge coefficient changes through the pressure conditions at the openings. This model uses a ventilation driving force, which is the difference between the wind pressure and the indoor pressure, and a dynamic pressure in tangential direction at the opening. The proportion of these two parameters is expressed as dimensionless indoor pressure (PR*), and the discharge coefficient and the inflow angle are decided by PR*.
 This study firstly examined the discharge coefficient changing mechanism on different PR* conditions with CFD (Large Eddy Simulation). The results show that total pressure loss coefficient is steady over all regardless of PR* differences, and that the static pressures increase widely by airflow crashes to window flames when dynamic pressure in tangential direction at the opening excels. The results also show that the cross-ventilation rate and the discharge coefficient decrease because airflows counteract from the static pressure increases to go through the openings.
 Secondary, this study conducted an examination with virtual stream tube to reveal the ventilation energy variation and the pressure loss mechanism after airflow passing through the openings. In the results, the dynamic pressure in tangential direction converted to the dynamic pressure in normal direction and the static pressure decrease appeared in the area where the dynamic pressure in tangential direction at the opening is relatively large (around the area where PR* is close to zero), and the dynamic pressure increase by vena contracta and static pressure decrease also appeared. The results shows that the turbulent kinetic energy production is one of the considerable factors of total pressure decrease.

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 The trajectory analysis of pedestrians using the tracking system of laser scanners is an effective approach for understanding the usage of facility spaces. Carefully looking at the pedestrian trajectories observed in an outpatient reception area of a hospital, we can find some specific patterns of patient behavior. For instance, some patients come in the area from the main entrance, line up at the return visit reception machines, and leave to the consulting room area slowly. Also, some coming from the main entrance, pass through the return visit reception machines, and leave the consulting room area quickly. These examples indicate that behavior patterns and attribute information of facility users can be estimated from their trajectory features such as directionality, staying place and walking speed. However, it requires a heavy load to manually extract the features from pedestrian trajectories and classify them into some adequate patterns. Hence, it is highly desirable to achieve this task automatically.
 In this paper, we proposed a method of pedestrian trajectory classification using the Restricted Boltzmann machine, by which we can automatically find the inherent features of pedestrian trajectories. This method was applied to an outpatient waiting area of a hospital. Comparing manual and automatic classification, we demonstrated the usefulness and sufficient performance of our proposed method in extracting the feature of directionality, staying place and walking speed. The details are as follows:

 (1) Modeling of pedestrian trajectory
 The trajectory data were divided into three-layers composed of 1 m square grids, which were consisting of “Front layer”, “Back layer” expressing the directionality, and “Staying layer” expressing staying places. The restricted Boltzmann machine had input units and binary hidden neurons, by which the feature of the trajectory data were generated after sufficient learning. In setting the number of hidden neurons, the 100 × 8 model, which had 100 neurons in the first hidden layer and 8 neurons in the second hidden layer, was applied by comparing the information entropy of the hidden layer.

 (2) Model validation
 In the 100 × 8 model, the degree of coincidence between the results by manual classification and automatic classification was examined. The entropy ratio, which is an index for checking the degree of agreement, was 0.6% in the entropy ratio by manual classification, and 10.6% by automatic classification. The results showed that the manual classification and the automatic classification was in good agreement. In addition, the trajectory distribution diagrams were configured for each machine classification, and the feature pattern diagrams were made by 2nd hidden neurons, which automatically found inherent features. These diagrams demonstrated the effectiveness of our proposed method.

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