日本建築学会環境系論文集
Online ISSN : 1881-817X
Print ISSN : 1348-0685
ISSN-L : 1348-0685
82 巻, 734 号
選択された号の論文の10件中1~10を表示しています
  • 西野 智研, 今津 雄吾
    2017 年 82 巻 734 号 p. 289-299
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     We proposed a probabilistic method for evaluating a hazard map for tsunami-induced fire. Accumulating combustible density is used as the indicator visualized on the map, which represents the fire vulnerability of an arbitrary point. The accumulating combustible density is evaluated on the basis of multiple accumulation scenarios and their occurrence probabilities using the existing model for the drift and accumulation of tsunami-driven combustible objects. Here, the following factors are defined as the uncertain factors which governs the accumulation scenarios: 1) sea level in the event of tsunami arrival, 2) damage of coastal structures such as a seawall, 3) damage of buildings, and 4) density of movable and fixed combustible objects loaded on buildings. A finite number of accumulation scenarios are sampled to evaluate the average and the standard deviation of accumulating combustible density using event tree and Monte Carlo simulation.
     We applied the proposed method to Yamada town in the 2011 Great East Japan Earthquake Tsunami to verify the evaluation characteristics. Field survey after the tsunami has reported that two fires broke out in tsunami inundation area of Yamada town and developed into spreading fires resulting in 16 hectares of burned area. As a result, the proposed method could estimate the actual fire damage zone plausibly, because high accumulating combustible density areas are concentrated within or around the fire damage zone. This result indicates that the accumulating combustible density is available as the indicator of tsunami-induced fire hazard map which represents the fire vulnerability of an arbitrary point.
     A tsunami-induced fire hazard map of future Nankai Trough Earthquake was estimated using the proposed method. Here, Shimoda city was adopted as the target area of hazard map estimation, and safety of tsunami refuge facilities against the fire was considered by overlaying the high grounds and the tall buildings on the map. The result shows that the hazard map estimated by the proposed method is useful for planning of location and fire safety of tsunami refuge facilities.
  • 岩田 三千子, 北本 裕之
    2017 年 82 巻 734 号 p. 301-308
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     In this study, the authors have sought under laboratory conditions to evaluate the visibility of the targets and the backgrounds consisting of 129 color combinations under two illuminance conditions. The results of our research are as follows:
     (1) The visibility of chromatic and achromatic color lines for visually challenged subjects suffering from defective eye conditions, such as retinal and or ophthalmological diseases, which included defective colour vision, were analyzed. Findings showed that subjects with diseases of the retina scored lowest for achromatic color lines. However, no significant differences were recognized between the groups suffering from defective eye conditions. Additionally, subjects with defective color vision showed low scores for the chromatic color lines.
     (2) The affirmation visibility rates of the achromatic color lines are represented by two graphs which show estimated formulas using luminance contrast or luminance ratio. Thus, a luminance ratio of 2 adhered to guidelines which indicated the leading road line for the almost half of the visually challenged subjects to be inadequate.
     (3) The affirmation visibility rates of the chromatic colour lines were greatly affected by the luminosity difference between the lines and the backgrounds.
     (4) The relationship between the affirmation visibility rates and chroma of 5R4, 5Y8, 5G5, 5B5 chromatic colour lines showed that as chroma increased, the affirmation visibility rate also increased. When the luminosity difference between these lines and the backgrounds increased, the effectiveness of the chroma did not impact upon the affirmation visibility rates. The 5Y8 line shows this characteristic especially.
     (5) The affirmation visibility rates of the 5R4, 5Y8, 5G5, 5B5 chromatic color lines are shown in the graphs, each with a rate of 10%. The affirmation visibility rates of chromatic color lines depend on the luminance ratio and the chroma is clearly depicted by these figures.
  • 原田 昌幸
    2017 年 82 巻 734 号 p. 309-315
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     Currently, a restaurant or a cafeteria is often used not only as a place to have a meal but also as a place to work, take a rest, or just kill time. This change has become significantly enhanced by the development and wider availability of wireless networking services that facilitate all types of internet interaction from recreational use to work from just about any place. At many self-service restaurants, customers can not only select their own seats but also move one or more tables together to create more space for themselves. However, when customers are allowed this freedom, it is not uncommon that other customers are inconvenienced because a single customer has taken up many seats, especially during peak operating hours.
     The objectives of this study are to identify and clarify the characteristics of seat use and over-use behaviors based on customer behaviors in the food court of a shopping mall.

     The observation target for this research was a food court in a large shopping center in Nagoya, Japan where customers are free to choose their seats and connect tables as they like. Activities besides eating and drinking, such as studying are also tacitly permitted by the establishment. The observation time was from 10:00 a.m. to 2:00 p.m. and included both crowded and relatively empty time periods. The observation survey was conducted on 13 weekdays and 10 weekends, and more than 600 groups and more than 1, 400 customers were observed. The observed items included customer age categories and gender (estimated by the observer), the number of group members, arrival and departure times, tables and seating choices, and the activities in which they engaged.

     After observation, it was found that the customers ranged widely in terms of age, from young children (even less than 10-year olds) to senior citizens, with a large number of teenage customers too. There were many single customers on weekdays, whereas on weekends nearly all customers were in groups. The seats chosen most often on weekdays were the bench seats with the atrium to its back, with a slight difference in choosing bench or chair seating on the weekends. Also, looking at how customers tended to choose seats, they regarded the distance or nearness to other customers, which indicated that interpersonal distance had an effect on seat selection in this study.
     Regarding extra seat usage, during the week people in age groups from teenagers to 40-year olds used seats for longer than necessary, with a shift on the weekends to teenagers and people in their 20s, especially teenagers. People who were engaged in chatting were the predominant long-users, with people studying on weekends spending inordinate amounts of time taking up space in the food court observation area during the hours of the study.
     Taking up extra seats was observed much more on weekdays compared to weekends, and decreased significantly on crowded weekends. During the week men more than women took up more extra seats, which likely reflects a cultural norm regarding personal space. However, on both weekdays and weekends, single people and people 70 years old or older tended to take up extra seats for themselves. Interestingly, during the week, resting and reading seemed to require the most seat overuse, but studying took over the number one slot on weekends, followed by resting and reading. Again, the need for more interpersonal distance might be important to being comfortable resting and reading in such a public place.
  • 西川 華乃子, 伊香賀 俊治, 近江 聡子
    2017 年 82 巻 734 号 p. 317-325
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     The reduced ability to exercise and the increasing prevalence of overweight and obesity in students have recently become serious health concerns. Decreased physical activity in students is cited as a factor in these problems. Governmental agencies have promoted improvement of the regional environment in order to encourage physical activity in students. However, there is insufficient quantitative verification of the regional environmental factors that affect the physical activity of students. Therefore, the purpose of this study was to clarify the relationship between the regional environment and physical activity in students, using a questionnaire survey and actual measurements of physical activity.

     A questionnaire survey was conducted for more than 300 teachers across 13 elementary schools to evaluate the satisfaction with the natural environment, the public security, the facilities for communication and the public facilities of each school district. Also, a measurement survey was conducted in the same public schools in Kawasaki city and data were obtained from 702 students aged 10-11 years old across 13 school districts. During a week of September to November 2014, the number of walking steps of each student was measured by a pedometer, HJ326F and HJA-350IT (OMRON).

     1) Impact of the regional environment on physical activity
     Using the results of a questionnaire survey and actual measurements of physical activity, we conducted the multi-level model analysis in order to clarify the impact of the regional environment on physical activity of students in taking account of individual attributes. As a result, for school regions where the satisfaction with the natural environment and the public security were high, the number of walking steps on weekdays exceeded those where the satisfaction was lower. According to the multi-level model analysis, the regional average number of steps increased by about 300 for every 1pt increase in the satisfaction score of the natural environment and the public security.

     2) Relation between satisfaction with neighborhood environments and land use
     Although we examined the relationship between the satisfaction with neighborhood environment and physical activity in students, a concrete factor which increases such satisfaction with regional environment was unclear. Therefore, we carried out a correlation analysis between the satisfaction score of neighborhood environments and the land use and the zoning of the regions. The satisfaction score of the natural environment of a region was correlated with the proportion of a forested region. We also examined the negative correlation between the satisfaction with natural environment and the proportion of a dense low storied building area.

     In conclusion, the result of this study confirmed a relationship between regional environment and physical activity in students and showed the significance value of the natural environment, the public security and the facilities for communication to encourage physical activity in students.
  • 実験BOX内におけるPCM熱容量変化の室温への影響検証
    武田 仁, 足永 靖信, 兼松 学
    2017 年 82 巻 734 号 p. 327-335
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     The use of phase change material (PCM) is considered to be an effective method for energy conservation in buildings. PCM has some attractive properties including light-weight compared to other building materials and increased heat capacity at a specific region of temperature.
     In the present study, the thermal behavior of PCM and the temperature fluctuation in the PCM-installed room were observed to examine by the room temperature variability analysis. The three-dimensional finite difference method were introduced to solve the three-dimensional nonlinear behavior caused by the inhomogeneity of PCM's phases, which the liquid phase, latent heat releasing/absorbing phase and solidification phase coexisted at a certain temperature range.
     In the proposed analysis, the PCM surface heat flow corresponding to the room temperature excitation was calculated and the endothermic response of PCM and the latent heat storage materials (A4 paper size) serving as furniture were considered to determine the weighing factors related to the room temperature fluctuations.
     As a result, numerical analysis on the room temperature, which is calculated through the process assigning weighting factors of room temperature fluctuation into thermal load calculation program (LESCOM-mint), successfully demonstrated the experimental results.
  • 開原 典子, 高田 暁
    2017 年 82 巻 734 号 p. 337-345
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     In order to clarify the influence of indoor temperature and humidity on the change in skin moisture content in daily life, skin moisture content of students engaging in sedentary works in a standard room in a university were measured along with the temperature and humidity of the room where the involving students were staying, from autumn to winter for two years.

     1) In the first year survey, the skin moisture content was measured for one subject. It was indicated from the 80% of the whole data that the fluctuation of the skin moisture content changed following the fluctuation of the indoor absolute humidity. Further, for the other 20% of data, it was possible to explain their behavior by spontaneous activities by the subjects and the outdoor climate such as rainfall or humidity trend. In addition, the correlation between skin moisture content and indoor temperature-humidity was studied, and it was shown that the absolute humidity showed the highest positive correlation among the indoor air temperature, relative humidity and absolute humidity.
     2) In the second year survey, the skin moisture content was measured for seven subject including one subject who attended the first year survey. As the result, it was shown that the indoor hygrothermal parameters (air temperature, relative humidity, absolute humidity) positively correlated with the skin moisture content and that the correlation coefficient with absolute humidity was the highest among the three parameters. At the same time, it was found that the daily fluctuation of skin moisture content followed the fluctuation of indoor absolute humidity, and this trend was common to all subjects.
     3) From the results for subject who was involved in the surveys for both years, the relationship between skin moisture content and indoor absolute humidity was found to be consistent.
     4) From the results of these investigations, it was shown that in ordinary daily life, the indoor absolute humidity has the stronger influence on the skin moisture content than indoor air temperature and relative humidity.
  • 王 美 楠 , 須永 修通
    2017 年 82 巻 734 号 p. 347-355
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     Economic growth and improvements in living standards have resulted in an urgent demand for comfortable and healthy building environments, and this has led to a sharp increase in energy consumption in China. Therefore, in order to achieve a good balance between environmental quality of indoor thermal environment and energy consumption, it is crucial to identify the actual residential energy demand and its influencing factors. In this study, the annual energy demand for a typical multi-residential building in China was dynamically simulated, and the influence of building thermal performance and air-conditioning setting temperature was studied for each climate zone in China. The results show that energy saving strategies in China should be implemented accordingly in response to different climate and geographical conditions. In the severe cold and cold climate zones that require greater levels of heating in winter, air tightness of building should be considered a priority, as better air tightness can deliver a significant heating energy reduction, whereas the quality of the wall insulation is the main contributor to the indoor thermal environment in winter for all climate zones. On the other hand, in the south of China, where comfort in summer is the main concern, the improvement of external window performance and the addition of external shading are the key issues that need to be addressed. Compared with the poor effects of lowering heating temperature in the north of China, raising cooling temperature in the south is relatively effective method to save energy without causing a sharp deterioration of the indoor thermal environment. It may be realistic to reduce energy consumption and ensure the quality of indoor thermal environment in multi- residential buildings by using the appropriate climate-responsive energy-efficient measures.
  • 菊本 英紀, 崔 元準, 大岡 龍三
    2017 年 82 巻 734 号 p. 357-365
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     Natural ventilation is a good measure to reduce the thermal load of a building and create a good thermal environment for the occupants. To predict the ventilation performance of a building, related ventilation parameters should be estimated. However, obtaining an accurate prediction or estimation before the construction is completed is difficult because of the fluctuating characteristics of turbulent, complex local flow field affected by surrounding buildings and city-scale topology. These problems make the application of natural ventilation difficult, and therefore, an in situ experimental method adopted after the construction of a building is completed would be a more reliable way of obtaining accurate ventilation parameters.
     The tracer gas method is a frequently used in situ method to examine ventilation performance. However, deterministic evaluation using this method has its drawbacks in terms of accuracy, and the uncertainty of results could be large because of fluctuating environmental conditions and intrinsic error of measurement. Therefore, when parameters related to natural ventilation are estimated, the estimates and their uncertainty should be concurrently evaluated.
     In this study, using a Bayesian approach, we propose a new estimation method that yields not only the estimates, but also the probability distribution of the estimates. To validate the proposed method, we reproduced a tracer gas experiment using computational fluid dynamics (CFD) simulation because the experimental absolute true values that are unknown in most situations were required for evaluating the proposed method. Using the data from CFD simulation, estimations of the ventilation rate and effective room volume were obtained using two different methods: probabilistic estimation based on Bayes' theorem, and deterministic estimation using the quasi-Newton method. In the probabilistic estimation, a method of simultaneously estimating the degree of the difference between the measurement value and the prediction value required for estimation was proposed.
     The estimation results showed that the estimated values of the deterministic method and probabilistic method (mode of probability distribution function) were very close to the true value set in the CFD simulation. However, the probabilistic method has some advantages over the deterministic method in that the former method can provide not only the estimates, but also the probability distribution of each estimate and its confidence interval. Additionally, in the case of a simultaneous estimation of more than two unknown parameters, it is important to analyze the correlation among parameters. By creating a joint probability density function, the correlation between the estimation parameters is determined, and this is another important advantage of the probabilistic estimation method.
  • 大塚 雅之, 松尾 隆史, 各務 紘史, 秋山 和也
    2017 年 82 巻 734 号 p. 367-375
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     There has been a strong demand for global warming countermeasures and water resource conservation measures, and water-saving toilets have been promoted worldwide. However, while various types of water-saving toilets are commercially available, data about discharge characteristics of each type or variations in the characteristics when being connected to the horizontal drainpipe are insufficient, and basic unit data used in the steady flow rate method by SHASE-S 206 are unclear. Moreover, there is no systematic understanding about the results of carrying performance experiments involving the simultaneous draining of toilet paper, etc. Therefore, the collection and disclosure of basic data is required for plumbing design that involves the installation of water-saving toilets.
     In response, the study examined fixture discharge characteristic values and carrying performance values by carrying out experiments. In the experiments, three water-saving toilet types; type I (low cistern system), type II (flushing valve system), and the common type, which are categorized by JIS A 5207-2014 'Sanitary Wares' according to the amount of flush water and the amount of drained water, were each connected to a fixture drainpipe (total length 16 m, pitch 1/100 and diameter 75A). Subsequently, the following knowledge has been acquired, which is useful for carrying performance and plumbing design.
     (1)Compared to types I and II, the average drainpipe-connected fixture discharge rate, qd', of the common type decreases gently and by a small amount along with the pipe length, and no significant difference is observed between type I and type II.
     (2)Five types of experimental waste substitutes were used in the carrying performance experiment, and the results confirm that the common type ensures a carrying distance of 10 m or longer (with nine bends), and types I and II ensure 4-8 m (with 3-7 bends) when using toilet paper (layered) which is a realistic waste substitute.
     (3)In each case of the five experimental waste substitutes, the relationship between the amount of flush water and the carrying distance has been clarified, and the approximate decrease in the carrying distance in line with the reduction of unit water quantity has been identified.
     (4)The average drainpipe-connected fixture discharge rate, qd', which serves as a carrying limit value, is approximately 0.3 L/s, which can be used as a standard value, and from the safety perspective, it is 0.5 L/s, which is roughly the same as qd' for bathtubs. Therefore, in a plumbing design that ensures good carrying performance, plumbing conditions should be determined within the ranges of pipe lengths and numbers of bends so that the qd' value is met at the end of the horizontal fixture branch.
     The acquired knowledge helps to understand basic unit data about discharge characteristics of different types of commercially available water-saving toilets and carrying performance (carrying distances and the number of bends) through simulation using a plumbing model. Furthermore, the study achieved its objective in providing basic data of fixture discharge characteristics for use in the steady flow rate method stipulated by SHASE-S 206 while ensuring good performance of carrying waste when water-saving toilets are connected to drainpipes. The next study will examine carrying performance when using experimental waste substitutes which are approved for use in the current BL testing, and will discuss the possibility of predicting discharge characteristics of different types of water-saving toilets and carrying performance (e.g., carrying distances) by using a numerical simulation model.
  • -エアコンの使用に関する実態調査-
    糸井川 高穂
    2017 年 82 巻 734 号 p. 377-383
    発行日: 2017年
    公開日: 2017/04/30
    ジャーナル フリー
     Introduction: Every year, 40, 000~50, 000 patients are admitted to hospitals owing to heat stroke. Specifically, the elderly experience such symptoms despite being indoors, especially when the air conditioner is wall-mounted. With age, thermal sensations decrease, and physiological responses to thermal conditions become weaker. Therefore, the appropriate use of an air-conditioner will not only lead comfortable indoor conditions but will also prevent heat stroke. However, it is known that the use of air-conditioners increases costs of electricity use. Being a parent/child, age, and sex impact decisions, e.g., keeping the air-conditioner on/off or setting the temperature. For example, the metabolic rate of elders is lower than that of minors.
     In the past, several studies have examined the relationship between the use of air-conditioning with age and sex based on data from physiological and psychological evaluations. This study aimed to analyze the relationship between the air-conditioner use among the elderly and their physiological and psychological differences.
     Method: I commissioned a senior college to distribute questionnaires. In the questionnaire, the respondent was requested to choose room type, age range, set temperature, and reasons for using or not using an air-conditioner. Reasons for using the air-conditioner were chosen from options such as “Hot,” “Humid,” and “No wind,” while those for not using the air-conditioner were chosen from options such as “Not hot,” “Not humid,” “Wind,” and “High electricity expense.” Additionally, the respondents were requested to report the set temperature that they generally preferred.
     I commissioned a college for the elderly to distribute 300 questionnaires to its students, in October 2014.
     Result and Discussion: In total, 35% of the distributed questionnaires were collected, which provided information on 227 air-conditioner units. About equal numbers of men and women used air-conditioners. Room type had no influence on the set temperature. “Hot” was the most commonly selected reason for using the air-conditioner, followed by “Humid” and “Room temperature.” “Not hot” was the most commonly selected reason for not using the air-conditioner, followed by “Not humid.” The average set temperature was about 26.5°C. Air-conditioner users decided to use it at the room temperature of 29.6°C.
     Conclusion: The results of the survey on the nature of air-conditioner use were analyzed with in accordance with the following four aspects:
     1. There was no difference in the set temperature between users (male/female) and the type of room.
     2. The average set temperature was about 26.5°C.
     3. Air-conditioner users decided to use it at 29.6°C.
     4. The main factors affecting air-conditioner use were high temperature and humidity. The main factors leading to non-use were bearable temperature/humidity, airflow, and costs of electricity use.
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