In this study, a series of experiments were carried out regarding water film flow formed by a water discharge system on the surfaces of steel shutters as a means to secure the thermal insulation of the steel shutter in order to ensure the fire spread prevention from the fire room to the adjacent space and the safety of activities of firefighters.
In this experiment, the steel shutters, which are three types (Type A1, A2, A3) of fire protection equipment, were used under non-heating. Each slat of Type A1, A2, A3 steel shutters is composed of the main curved surface portion and the connecting portion. The steel shutter used in the experiment has dimensions of approximately 1000 to 1100 mm in height × 500 mm in width. The number of connected slats is 11 for Type A1 and A2, and 9 for Type A3. In addition, in order to compare with the steel shutter, an experiment using the steel plate with a height of 1000 mm × W 500 mm was also conducted. The steel shutter surface was painted in matte black to suppress the generation of reflected light due to illumination. The amount of water Ws supplied to the steel shutter from the slit of the water discharge system was set to five conditions of 10, 12.5, 15, 17.5 and 20 [L / min]. In this experiment, the water film flow formed on the shutter surface where the convex side of the main curved surface of the slat continued was observed. In this study, basic knowledge on water film properties was collected and discussed, focusing on the velocity and the arrival time of the water film flow formed on the steel shutter surface under non-heating.
Next, the temperature distribution etc. of the steel shutter (Type A2 and A3) formed water film were investigated under heating condition by the radiation panel.
As a result, the following findings were obtained:
(1) Water film flow properties formed on the steel shutter surface
The velocity of water film flow on the surface of steel shutter was analyzed by direct cross correlation method using PIV system. Water film accelerates on the main curved surface portion of the slats and then decelerates near the connecting portion between the slats. As water film moves from the connecting portion onto the main curved surface portion of the lower slat, it flows down while accelerating again.
The peak value of the velocity of water film flow on the main curved surface of the slat tends to decrease slightly as the distance from the slit of the water discharge system increases. As a factor which becomes such a tendency, the influence of the water droplet scattered from the water film formed on the shutter surface can be considered.
The arrival time of the water film flow on the surface of steel shutter tends to be about 1.6 to 1.9 times longer than the time of the flat steel plate.
(2) Thermal insulation effect by water film flow formed on the surface of steel shutter exposed to the radiation heat
As the incident heat flux to the specimen becomes higher, the temperature rise value at the same distance Dx from the slit of the water discharge system tends to increase almost in proportion to the incident heat flux. In addition, the temperature rise value tends to be higher as the distance Dx is longer and the amount of supplied water is smaller.
The β value tends to be slightly lower than the value obtained using steel plates in the previous study (β = 2.3 × 10-4).
Many human-environmental models were proposed by researchers of environmental psychology and surrounding fields, in order to deepen the understanding. Proposal of those models often defines and differentiate similar conditions and/or expand the usage of the former proposed model. For example, Kuno et al proposed two-dimensional thermal sensation model that introduced surrounding environmental index axis and thermal physiological index model, which differentiated “hot” to “warm” and “comfort” to “pleasant”. Likely, model of two turning points introduced by Hirate et al differentiated the type of decision, namely one turning point and two turning points. One turning point is where decision only changes once, like good / bad. Two turning points was where decision changes twice, like bad / good / bad, which indicates the adequate range. In addition, this model was developed from model proposed by Thustone, which adapted the model to experiments done by pairwise comparison method. Hirate et al not only introduced the model with two turning points as an expansion of the model, but also developed the model to explaining the experimental results of semantic differential method.
In chapter 2, model of two turning points is explained to discuss the limits and problem it holds. Two problems were shown. One is the premises of homoscedasticity, and second is the application to the experiment conducted using semantic differential method. To verify homoscedasticity (chapter 3), Bartlett test was conducted using data of pleasant lighting environment experiment obtained by adjustment method. As a result, homoscedasticity wasn’t shown under several bright conditions. In case of experimenting under broad range, this premise might not be fulfilled. However, there are two mathematical importance to this model. One is that P distribution is obtained by two times integration of R distribution (Eq. 5). Other is that this model can be interpreted by cumulative distribution function with the average of the true reaction (Eq. 6). To test the latter importance, goodness of fit test was conducted with normal distribution and logistic distribution. Both distributions fitted, and to expand the application of the model, the data was applied using multinomial logistic analysis and sequential logistic analysis. Both applied, which showed the possibility of adapting the model to non-equal variance data.
In chapter 4, the first mathematical importance was verified, using quartic function. If P distribution was obtained by two times integration of the R distribution, then known P distribution may be used to calculate the unknown R distribution. By setting the inflection points as two turning points, quartic function is applied to the known P distribution, and two times differentiation was done to obtain unknown two turning points. Further considerations on constraint condition has to be done, yet expansion of the model was shown.
The model with two turning points was re-considered using the data obtained by adjustment method. Unlike the premises of the model, homoscedasticity was not proven, yet through adaptation of logistic analysis, it was shown that model can be applied to cases of non-equal variance. In addition, through mathematical analysis, quartic function was applied and two unknown turning points were calculated, showing the new application of the model.
In the development of the sound insulation structures for buildings, evaluation of sound reduction index R is performed by laboratory measurement in accordance with JIS A 1416. Regarding multiple-layered structures with composite elements that are often used in building walls, assessment of low-frequency resonance transmission is crucial in the evaluation of their insulation performances. Implementation of numerical simulation on laboratory measurement of such complex structures is expected to contribute to improvement of efficiency in performance evaluation and to elucidation of sound transmission phenomena. The purpose of this paper is to simulate laboratory measurement of airborne sound insulation performances for composite members used in building walls by applying finite element method (FEM) and to validate the simulated results in low frequencies.
First, aiming to evaluate the wall structures for the separating walls in RC apartment buildings, measurement of sound reduction index R for an RC single wall and multiple-layered composite walls composed of RC panels and additional linings was performed in Type I reverberation room in accordance with JIS. Measurement of wall vibration due to acoustic excitation was also performed to observe the characteristics of the test walls.
Then, numerical simulation of the sound insulation measurement was performed using FE models where the entire sound fields of the source and receiving room were reproduced. The detailed structures of the test walls were modeled using elastic elements for the RC panels, the steel studs and the stud supports, along with plate elements for the gypsum boards. The material properties of the wall elements such as loss factor for the additional linings and Young’s modulus for the support material were identified experimentally. R was calculated for the frequency range of 50 to 315 Hz 1/3 octave bands.
The models of the RC single wall with several support conditions were investigated, and the analyzed results of R showed that some models succeeded in partially reproducing dips corresponding to the measurement, suggesting the possibility of simulating sound insulation performance for elastically-supported heavy-weight panels as targeted in this study.
The calculated results of R for the two composite walls exhibited that the models with limited simply-supported edges for the RC panels correspond to the general trends of the measured results in the frequency range above 100 Hz 1/3 octave band. Furthermore, the calculated results of sound reduction improvement index ΔR for the composite walls demonstrated the trend of decrease in value due to the decline of the degree of constraint in the RC panels, indicating the importance of the boundary condition of the basic wall in evaluating the influence of low-frequency resonance transmission by additional linings.
Although the simulation of the low frequency sound insulation for the composite members was validated within the scope of the experiment and the targeted frequency ranges, it is considered extremely important to obtain knowledges on modeling various measurement conditions through experimental and numerical investigations to improve the applicability of the simulation.
Traffic vibration causes problems from a viewpoint of habitability. In recent years, due to the densification of the city and the development of the transportation network, it is difficult to take enough distance between living space and road or railway which are vibration sources. Therefore, the problems due to traffic vibration are increasing. The aim of our study is to establish assessment measures for traffic vibration. The characteristics of traffic vibration are non-stationary vibration whose amplitude changes momentarily and multi-direction vibration.
In this study, we conducted sensory evaluation tests using the vibration waveforms measured in the housing, and considered a performance value that is relative to a human sense of vibration.
The investigated procedure is described as follows;
1) The traffic vibration waveforms measured at the upper floor of a wooden house near a road or railroad were selected.
2)Two sensory tests were conducted in the same way. The first sensory test is for fore-and-aft vibration, and the other sensory test is for dual-axis vibration. At the sensory tests, the panels were made to experience sample vibration on the shaking table and answer how they felt it. The sample vibrations were made by changing the amplitude each of waveforms selected 1) to several levels.
3)From the panels answer, we constructed psychological scales of feelings of amplitude, annoyance and discomfort against various vibrations using a method of successive categories.
4)We calculated several kinds of performance value candidates which were supposed to correspond to human sense and examined the correspondence with the psychological scales.
The results are described as follows;
1)The performance values VLT(630ms, 57dB), VLT(630ms, 60dB) and VLT(630ms, 62dB) of lateral vibration presented in the previous paper are applicable to the evaluation of fore-and-aft vibration. These performance values consist of the maximum value of vibration level and duration time of vibration. It is written as follows;
VLT=VLmax+20 · log10T1/4
Where, VLmax is the maximum value of vibration level (time constant is 630ms), T is total time when vibration level is exceeding 57dB or 60dB or 62dB.
2)Human’s sense of vibration is more severe in the fore-and-aft direction than lateral direction. VLT(630ms, 60dB) corresponding to the same evaluation is smaller by about 2.4 to 4.1 dB in the lateral vibration than in the fore-and-aft vibration.
3)The performance value C(1:√2)VLT(630ms, 60dB) is applicable to dual-axis vibration. C(1:√2)VLT(630ms, 60dB) is calculated from a value obtained by multiplying the RMS acceleration value in the fore-and-aft direction by √2 (+3dB) and combining it with the RMS acceleration value in the lateral direction.
In this study, we clarified how the shelter suppresses salt damage at Motomachi Sekibutsu, that is stone Buddha directly carved into a cliff at Motomachi, by calculating the hygro-thermal environment in the shelter. By numerical analysis, we modeled the cliff including the stone Buddha in two dimensions and the wall of the shelter in one dimension, and analyzed the heat and moisture behavior. In addition, we built a combining model to calculate the temperature and humidity in the shelter, and we verified the validity about the analytical results by reproducing the hygro-thermal environment in the shelter during the period from November 2014 to October 2017. We quantitatively estimated the risk of salt precipitation and salt damage by the hygrothermal properties in the stone Buddha, assuming that the amount of salt precipitation is proportional to the amount of evaporation from the statue and salt damage occurs during when salt(sodium sulphate) changes its phase. By using those models, we divide the renovation of the shelter into three elements: improvement of the thermal insulation, air tightness and shielding of solar radiation. The main results obtained by numerical analysis are described below.
1. By the renovation of the shelter, the amount of evaporation from the surface of the stone Buddha is suppressed by all the elements.
2. Focusing on the seasonal change in the amount of evaporation, it is possible to suppress the evaporation in summer, but difficult in winter except for the thermal insulation renovation.
3. In the study on the phase change of sodium sulphate, since the relative humidity in the shelter is higher than before the renovation and the hygrothermal property of the surface of the statue have become unfavorable to Thenardite, it is considered that the number of phase change about sodium sulphate is reduced. In other hand, if only we improve the air tightness, temperature in the shelter is kept high and it is easy for sodium sulphate to change its phase into Thenardite, so it may not be possible to say that the risk of salt damage has been generally suppressed.
4. When all the renovations are carried out (i.e. after the renovation), it is considered that the amount of salt precipitation and the the number of phase change about sodium sulphate are significantly reduced, so the risk of salt damage is suppressed.
Future issues are as follows. In Motomachi Sekibutsu, as a result of renovation of the shelter, the relative humidity in the shelter has become more humid throughout the year. In such a high humidity environment, there is a high risk of mold growth and we concern about the influence on the health of the visitor. In addition, as long as there is a huge water supply source such as groundwater, it is difficult to suppress the evaporation from the statue completely. Therefore, since salt is gradually accumulated in the stone Buddha, it is considered that the precipitation salt cannot be suppressed completely. In particular, the latter problem cannot be solved only by controlling the hygrothermal environment in the shelter, so we will start developing a technology to remove the salt accumulating in the statue. Furthermore, it is necessary to consider the preservation and exhibition method of Motomachi Sekibutsu based on the health risks of visitors and the preservation of the statue.
The purpose of this paper is to derive the numerical expressions on the air velocity and the neutral plane height at the indoor and outdoor boundary area from the theory of gravitational flows through a single opening.
In Chapter 2, we examined the relation between steady-state condition and mass flow balance in gravitational ventilation through opening. From the consideration based on the formula which is expressing the air volume difference in gravitational ventilation, it was shown that steady state conditions both of flow rate and temperature are necessary for the assumption of mass flow balance in the same space volume. This condition is not general as a condition of a room where ventilated by gravitational flows. Thus, the numerical expression that simply assuming mass flow balance cannot be adopted to general conditions. In this paper, we derived the mass conservation formula (4) corrected with the coefficient rm in order to apply the mass conservation law to the same space volume, assuming that the room temperature changes due to gravitational flows.
In Chapter 3, we applied the energy conservation law to the area through which air flows by gravitational ventilation, and derived the basic formula (6) considering mass flow correction and discharge coefficient. The formula (7) for obtaining the boundary air velocity, and the formula (10) to determine the neutral plane height are also shown. And the conventional numerical expression of gravitational ventilation can be considered as a formula assuming an external reference point where the windward dynamic pressure is 0. We also corrected the conventional formula obtaining neutral plane height, and derived the formula (11). The inclination of the neutral plane height which appears in the calculation result of CFD was explained by this formula.
In Chapter 4, in order to verify the theory of gravitational ventilation shown in Chapter 3, numerical experiments using CFD and calculation results of each formula in Chapter 3 were compared. As a result, the air velocity distribution and the neutral plane height calculated from the equations shown in this paper coincided with CFD and the theoretical validity was proved. On the other hand, in the conventional numerical expressions, since the dynamic pressure distribution at the boundary area was ignored, there was an error in the neutral plane height and the air velocity distribution.
The high cost of improving thermal insulation performance in houses is one of the hindrances to the spread of the improvement in thermal insulation performance, and it takes a long time to recover these costs through reduction of heating and cooling costs alone. Under such circumstances, in recent years, it has been reported that improvement in thermal insulation performance reduces the likelihood of various diseases among people inhabiting these houses, and this reduces medical costs. However, the relationship between thermal insulation performance and medical costs has not been quantitatively evaluated. If medical costs in relation to the thermal insulation performance of a house can be evaluated quantitatively, they can be taken into consideration in the recovery period of the costs of the improvement of the thermal insulation performance. Furthermore, it is possible to examine the most economical thermal insulation performance when considering the costs for thermal insulation, heating and cooling costs, and medical costs together.
Therefore, in this study, we estimated the medical costs in relation to the thermal insulation performance of the house, and examined the thermal insulation performance that is most economical when the costs for thermal insulation, heating and cooling costs, and medical costs are considered. Furthermore, we examined the cost recovery period for the improvement in the thermal insulation performance from that which satisfied the 2013 standard to the above-mentioned most economical thermal insulation performance, taking into consideration the reduction in heating and cooling costs and medical costs.
We assumed that the onset of various diseases is not directly affected by the thermal insulation performance of the house, but is affected by the thermal environment in the house, which is formed according to the thermal insulation performance of the house and the heating and cooling method. On the basis of the relationships between insulation levels of various houses and improvement rates in various diseases shown in the previous research, we estimated the thermal environments in houses in correspondence to each level of insulation and estimated medical costs from improvement rates in various diseases. We proposed formulas to estimate the medical costs for heart diseases and vascular brain diseases from the mean daily minimum operative temperature of the house from February 1 to February 7 and formulas to estimate the medical costs for diseases, excluding heart diseases and vascular brain diseases, from the mean operative temperature of the rooms the family inhabits from January 1 to February 28. We proposed these formulas separately for the age groups 0 to 19, 20 to 39, 40 to 59, and 60 and older.
Furthermore, using these formulas, we examined the most economical insulation performance, including insulation costs, heating and cooling costs, and medical costs. The average heat transmission coefficient of the envelope (UA value) of a house having this most economical insulation performance is 0.4 to 0.5 W/m2K for a floor-insulation house, and 0.36 to 0.4 W/m2K for a foundation-insulation house. We found that by considering not only heating and cooling costs but also medical costs, the cost recovery period for the improvement in the thermal insulation performance from that which satisfied the 2013 standard to the above-mentioned most economical thermal insulation performance was significantly shortened, to around ten years.
According to statistical data reported by the Japanese government, the major causes of death for Japanese people are cancer, heart disease and cerebrovascular disease. The incidence rate of cerebrovascular disease in particular is higher during winter than summer (Hayama, 2011). One possible reason for this seasonal difference is that exposure to low temperatures can cause fluctuations in blood pressure. In houses with poor thermal insulation, indoor temperature differences between heated and non-heated spaces, such as the bathroom, corridors, and lavatory can be larger during winter. Many houses in the Tohoku region have a poor thermal environment during winter, and the incidence rate of cerebrovascular disease in this area is the highest compared to the other areas in Japan. Hasegawa and Yoshino (1985) investigated indoor thermal environment in houses of Yamagata prefecture, which is included in Tohoku region, during the heating season and the death rate of cerebrovascular disease in 1983 and 1984. As a result, the temperature difference between the heated living room and the unheated rooms was found to be great. Also it was revealed that if the lavatory temperature was low or the bedroom was not heated, the occupants living in such houses statistically tended to be susceptible to cerebral vascular accident.
In order to clarify the association between the indoor environment of residential buildings and cerebrovascular disease, an epidemiological survey of 188 elderly persons living in Yamagata Prefecture in the Tohoku region of Japan was conducted. The specific areas investigated included three rural towns (former Yahata town, former Haguro town and Asahi town) and these areas are same as the investigated areas about 30 years ago. The survey was divided into three phases. The first phase (Phase 1) was a cross-sectional questionnaire on housing characteristics related to the indoor thermal environment and occupants' lifestyle habits among elderly persons. This paper describes the results obtained from this questionnaire and presents the characteristics of the indoor thermal environment and occupants' lifestyle habits during winter. Moreover, an association between the increase in rate of death due to cerebrovascular disease and factors that influenced the indoor environment of houses is examined using multivariable logistic regression analysis.
The multivariable logistic regression analysis shows that always feeling a draft in the living room while operating heating equipment (AOR, 8.14; 95%CI, 1.55-42.8) and low temperature in a living room at morning (AOR, 0.87; 95%CI, 0.78-0.98) was positively associated with an increased rate of death due to cerebrovascular disease for former Yahata town. These results indicate that a poor indoor thermal environment may contribute to an increase in the rate of death due to cerebrovascular disease. In addition, a high salt diet may contribute to the onset of cerebrovascular disease. When participants moved from a living room to a bathroom during winter, they reported thermal sensations, such as ‘warm’, ‘neutral’ and ‘cold’. AOR for ‘cold’ when entering a bathroom (AOR, 0.17; 95%CI, 0.05–0.58) was significant for former Yahata. These results indicate that occupants in this town did not feel cold, although the indoor temperatures among surveyed towns were similar. AOR for light clothing when staying at home was significant for former Yahata town and participants were thinly dressed during heating season. Therefore they may be more readily exposed to a cold indoor environment than other towns.
The purpose of this study was to clarify the individual difference of participants in “Wooden Craftsmanship Activity (WCA)” based of the questionnaire to the university students. There are few study related for wooden craftsmanship including design education that searching the individual difference of each group which clarifying the effect of the activity. In this study, the influence from architectural design education through field research, planning, design, production, presentation, contribution to the local and activity of WCA which is related environment education is focused.
WCA activity including design education developed as environment education and contributing to the local in Mountain Villages, Miyama-cho Nantan City, Kyoto. However, the education effect is different depends of the participants, the choice of the best education method is expected. And identification of individual difference is required for that.
Following is the finding through the research.
1) Based on the questionnaire about the effect of participating WCA, 3 components are extracted. It is “Contribution to the Local”, “Forest conservation”, and “wooden craftsmanship”. And participants are clarified into 4 group as “Local contribution”, “Craftsmanship”, “The middle”, and “Environment conservation”.
2) The students in the group of Contribution to the local is heighten the sense of contribution to the local and environment conservation based of the various experience with positive attitude. They seize their own experience and actual feeling effect to the sense of environment conservation and action.
3) The students in the group of design is tend to seize the area objectively. They feel communication with locals such as homestay as the way for product design include filed research and hearing reserch. It is possible to raise their forest conservation sense through the production program themed sustainable design.
4) The students in the group of middle is deepen the though and showing the motivation through the real size production activity. However, the many of them is modest and taking the middle way.
5) The students in the group of environment conservation may can not feel the effect because of the excessive work which is not the reason to participate to the WCA activity. They may require the program of the forest conservation and timber inderstry. And they seize the conversation with local people and friends give influence to the environment conservation and action.
In this study, we search the identification of the participants based on the clarification of the effect of WCA. It is reveled that heighten the educational effect of the WCA the care for the various aspects are required. This study targeted the limited number of participants, but as the study related to the wooden craftmanship including design education it can be said to get some results. The comparison with the other WCA and the research with the local residents is an issue in the future.
Animals raised in elementary schools are relevant to several subjects in the curriculum, with educational goals such as “life dignity, ” “nature providence, ” and “kindness to animals.” Outside the curriculum, raising animals in schools is increasingly necessary because of changes to children’s social circumstances, such as the decreasing number of siblings and the reduced number of animals being raised at home due to changing house environments. Although the need for raising animals in schools is recognized, more schools are no longer raising animals because of several problems, such as the increased number of children with allergies, the care that is necessary during school holidays, and the severe climate during hot summers.
The purpose of this study was to suggest animal-raising spaces and their environments in accordance with the present constraints issues in schools. To accomplish this purpose, the study consisted of two parts: the first part aimed to understand the changes that have occurred over time in animal-raising environments and educational goals － a history of raising animals in schools that dates back to the 1900s. The second part aimed to reveal the problems and clarify the space requirements for animal-raising environments in today’s elementary schools through a fieldwork survey, a questionnaire survey, and interviews with teachers.
Research about changes in animal-raising environments were as follows: an outside hutch for raising animals has been used for a long time, but the way of using the front space of hutch for children to observe animals as well as the outdoor space around the hutches have changed.
Research about the problems of and requirements for animal-raising environments in current school systems were as follows: many teachers selected “outdoors” as an ideal animal-raising space, but some teachers selected “entrance hall” and “classroom.” Each space has different advantages and disadvantages. It also has a different tendency in the choice of animal species ; that is, there is diversity in the animal-raising environment that schools require.
These studies show that the animal-raising environment most suitable for the current elementary school system, aiming at the next-generation type, is as follows: it is necessary to prepare variations of raising environments in a school. At the same time, an animal-raising environment and system should be prepared so that schools can ask for and accept the cooperation of regional habitants or animal experts. Through this study, we can suggest various style choices that each school can utilize, depending on their management and educational goals.