日本建築学会環境系論文集
Online ISSN : 1881-817X
Print ISSN : 1348-0685
ISSN-L : 1348-0685
81 巻, 727 号
選択された号の論文の12件中1~12を表示しています
  • 鈴木 一幸, 久田 隆司, 大宮 喜文
    2016 年 81 巻 727 号 p. 739-747
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     To prevent spread of a fire, the glass that has fire prevention performance has to be used in windows of fire proof walls. The glass called fire glass is generally used for that, and now fire glass panes have been used very much. On the other hand, from the point of view of energy saving, windows tend to be the weak point in the daily life, and the glass of which high heat insulation and the solar shading effect of the Low emissivity (Low-E) Insulated Glass Unit (IGU) is widely used. Although Low-E glass is used to shade solar radiation heat of infrared wavelength domain, the effect can also be shown to the radiant heat by fire as well as sunshine. Now many Japanese window-manufacturers acquire the certifications as the Low-E IGU combined with wired glass or heat-resistant tempered glass for house windows. If it would be possible to reduce the radiant heat flux of fire, Low-E glass can be expected as glass for prevention of fire spread from windows in a crowd uptown.
     Therefore the purpose of this study was to clarify fire prevention performance of the Low-E glass on fire by checking the breakage of glass and the radiant heat reduction effect.

     The fire test condition is shown below.
     ·Fire tests were performed for Low-E coating single glass pane coated one side, and each Low-E glass pane was heated with the both sides along the ISO834 Heat Curve for each specimen. (Figure3)
     ·The temperature of the glass was measured by thermocouples and ΔT was defined as the temperature difference of the center of glass and the edge of glass. The radiant heat flux was measured 1.0m away from glass surface by a heat flux gauge. (Figure4)
     ·In these fire tests, Low-E coating glass panes of emissivity value 0.05±0.02 , 0.15±0.02 and no coating glass panes were used.

     Findings are as follows.
     1) Figure8 and Table 3 shows that when Low-E coating glass is heated on coating side, temperature difference(ΔT) decreases by the radiant heat reduction effect of the Low-E coating. Therefore if the Low-E coating side is heated, the strength of the Low-E glass can be lowered.
     2) Figure12 shows that by the data obtained from the fire test, relations with ΔT and the surface compression is led, the relation has a strong correlation by being classified in every emissivity value.
     3) Figure15 shows that by consideration of glass surface heat balance, temperature reduction by Low-E coating is obtained, the relation of glass surface compression and temperature difference can be expressed in the same way as no coating glass.
     4) Figure13 shows that radiant heat flux is lowered as the value of Emissivity of Low-E glass is Low, Low-E coating glass which has emissivity value 0.05±0.02 can reduce around 90% of radiant heat in comparison with no coating glass.
     5) Figure24 shows that radiant heat flux from glass on fire can be explained by transmission of spectral characteristic of the radiant energy on fire and radiant heat flux from the unheated glass surface temperature. The radiant heat flux from a fire can penetrate no coating glass, that can’t do the Low-E coating glass with emissivity value 0.05±0.02. That is, if Low-E is coated on heating side, radiant heat flux depends only on the glass surface temperature.

     In this study, the strength of glass was defined as glass surface compression. However not only the surface compression but also glass edge strength is very essential for glass breakage evaluation, so that needs further consideration.
  • 冬期の視覚・聴覚要因等を活用した住まい方に関するアンケート調査より
    福坂 誠, 松原 斎樹
    2016 年 81 巻 727 号 p. 749-756
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     The authors perceive the living environment of existing houses as a complex environment entity surrounded by light, heat, sound, air, etc., while focusing on the psychological conditions of the residents and their behavior. We then devised a plan for the residents to endure heat and cold by practically using audio-visual stimuli etc. to mitigate thermal discomfort. Further, we proposed a hypothesis of this study leading to an energy-saving way of living and conducted field studies at actual households. The previous survey report regarding the season of summer revealed the residents' behavior of obtaining coolness through audio-visual stimuli etc. by means of sprinkling water, changing rugs in accordance with the season, and using glass tableware, etc., and not simply obtaining coolness from air conditioners and electric fans.
     The purpose of this research is to investigate energy conservation and the facts regarding the practical use of audio-visual stimuli etc. by studying the behavior of housing residents to obtain warmth in the winter. The authors collected the responses from residents of detached houses using a questionnaire regarding the use of heating equipment in winter, the implementation conditions, and reasons for the behavior of obtaining warmth, as well as information concerning the awareness, values, and physical constitution of the residents. The survey was conducted in the Nijojo-kita area of Kamigyo-ku in Kyoto City, where the previous summer survey was conducted. The survey was distributed to 600 households in the district and responses were received from 196 households via mail, with a collection percentage of 32.7%. The questionnaires were distributed in late March 2011 and returned in mid-April of 2011.
     The information obtained from this study can be summarized as follows:
     (1) The study revealed a diversity in the choices of the residents to obtain warmth.
     (2) The residents were classified into four groups based on questions relating to awareness, values, and physical constitution by extracting the two components: “degree of emphasis of tradition and sense of the season” and “tolerance to cold and the degree of endurance.”
     (3) Groups 2 and 3 are tolerant to cold and cope with the heat or cold by adjusting their clothing rather than the temperature. Also, by implementing the behavior of obtaining warmth from other than a heater, they tend to have reduced heater usage time.
     (4) Groups 1 and 4 placed importance on the ‘degree of emphasis of tradition and sense of the seasons’. While the groups obtain thermal warmth from a heater, they also emphasize the ‘sense of seasons’ by a warm appearance of rugs and warm colored interiors. This group implemented more behaviors of warmth from psychological and visual stimuli.
     (5) Group 1 and 4 evaluated the comfort of their residence to be high and their tolerance level of thermal comfort through psychological and visual stimuli etc. was similar to that of the summer season. These groups demonstrate energy-conserving living without being overly dependent on heaters.
  • 加藤 洋子, 明石 行生, 菅野 普
    2016 年 81 巻 727 号 p. 757-764
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     In order to reduce global warming while maintaining occupants' health it is important to make the best use of daylight in interior spaces. To maintain comfortable interior environments while utilizing daylight it is necessary to control window luminance appropriately. To this end, many researchers have referred to discomfort glare from high-luminance windows. However, since recent office workers often perform visual tasks by using computer displays their visual performances are susceptible to high-luminance windows. Ocular light scatter covers the entire visual field of a worker, and therefore often reduces the luminance contrast of a target against its background.
     The purpose of this study was to investigate how a high-luminance side window impairs visual performance of a computer task. Subjects were asked to detect targets presented at the central and peripheral visual field, and the subjects' response times were measured. In order to investigate the mechanisms of how window luminance affects target detections, veiling luminance on each target caused by the window was calculated under each of the experimental conditions. The findings of the study are listed below.
     1) The high-luminance window behind the computer display significantly impaired the detection performance of targets presented on the computer display. As the luminance of the window increased, the visual performance was decreased. The validity of the experimental dataset was confirmed by comparing the dataset with existing experimental data.
     2) When window luminance exceeded a certain luminance between 3000 cd/m2 and 6000 cd/m2, visual performance was deteriorated significantly. This implies that window luminance should be reduced to lower than 3000 cd/m2 for computer tasks.
     3) Evaluations of discomfort glare did not necessarily correspond to visual performance. Therefore, in order to design windows for efficient task environments it is important to minimize the effects of windows on discomfort glare and visual performance.
  • 山本 果奈, 明石 行生
    2016 年 81 巻 727 号 p. 765-773
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     General lighting has been widely used for office rooms in Japan. However, to reduce energy consumption it is important to use task and ambient lighting (TAL) systems in office rooms. It is known that TAL systems can minimize electric energy consumption without compromising lighting quality in office rooms To make TAL systems be used more widely in office rooms, it is important to take any measures to improve lighting quality, especially perceived room brightness in office rooms which employ TAL systems.
     We conducted two experiments in a real office room and 1/10-scale office model rooms. In the real office experiment, we employed a proposed TAL system that adopts suspended indirect luminaires as ambient lighting. This is because we hypothesized that the proposed TAL system could reduce gloomy non-lit areas by the indirect ambient lighting and therefore increase perceived room brightness. We measured the energy consumption of the office room and evaluated the quality of the working environment by using questionnaires. From the results, we found that the proposed TAL system with indirect ambient lighting helped reduce deep shadows and discomfort glare, and therefore improved its lighting quality. In addition, the TAL system with indirect ambient lighting reduced lighting energy by about 40% from conventional general lighting.
     In the additional laboratory experiment using 1/10-scale models, we compared the lighting quality of the TAL system using indirect ambient lighting with a TAL system using direct ambient lighting, a TAL system with dimmed ambient lighting, and a general lighting system. In this experiment, we confirmed the results of the real size field experiment and found the lighting quality of the TAL with indirect ambient lighting to be better than the other lighting systems.
     However, this study found the brightness uniformity of the TAL with indirect ambient lighting to be worse than the general lighting and TAL with direct ambient lighting systems. On the other hand, physical indexes such as luminance uniformity (minimum luminance over average luminance) and luminance variation coefficient (luminance standard variation over average luminance) showed better performances for the TAL system with indirect ambient lighting than for the other lighting systems. This implies that luminance modulations within a certain special frequency range may influence perceived brightness uniformity and therefore perceived room brightness. Further research is needed to investigate the mechanisms of how people evaluate uniformity of luminance distributions in lit office rooms.
  • 不満足者率及び投入熱量による空間的不均一性の評価手法の提案
    清野 新, 前 真之, 佐藤 誠, 赤嶺 嘉彦, 高瀬 幸造, 芹川 真緒, 米澤 星矢
    2016 年 81 巻 727 号 p. 775-783
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     Inside the housing, the thermal environment is uneven in terms of vertical temperature, horizontal temperature, mean radiant temperature and draft because of the thermal insulation, plans and the heating system. According to ASHRAE Standard, the comfortable thermal environment is defined as that “PMV is within comfortable range with Predicted Percentage of Dissatisfied of floor temperature, vertical temperature, draft and uneven mean radiant temperature low”.
     According to the previous researches dealing with subjective experiments and human body models, mainly evaluating the local thermal discomfort by parts of human body where the subject or human body model is located. On the other hand, a room with uneven thermal environment because of a large window and so on, needs to be evaluated not only at the center point but also for each distribution. Properly speaking, the thermal environment should be evaluated in terms of the heat balance of a human body. But in this research, first, in order to research the basic study of the thermal environment caused by both of the thermal insulation and the heating system, set a temporary evaluation index of total predicted dissatisfied as “PDall”, which is taking air temperature, mean radiant temperature and draft into account, and analyze the relationship between the distribution of that index and thermal load. Through CFD analysis, changing the parameters of the thermal insulation and the heating system, learn the tendency of distribution of the uneven thermal environment. Based on the results of CFD analysis, develop a thermal network calculation model reproducing the tendency of the vertical temperature and draft in CFD. Calculating more cases with this, analyze the relationship between both of the thermal insulation and heating system and both of the uneven thermal environment and the thermal load.
     As a result, the thermal environment becomes more uneven as the thermal insulation gets worse. With convention air-conditioner heating, the thermal unevenness is mainly composed of the vertical temperature and draft, and depends on the supply wind speed, with supply wind speed higher, draft becomes stronger and thermal temperature less. With underfloor heating, the thermal environment is almost even. With radiation heater such as stove or heating panel, the thermal unevenness is mainly composed of the vertical temperature and mean radiant temperature, and depends on the radiation area, with it larger, the vertical temperature becomes more uneven and mean radiant temperature more even.
     In this research, through the CFD analysis and the thermal network analysis, reveal the relationship between the thermal insulation and the heating system in terms of the thermal unevenness and the thermal load.
  • 大阪市の集合住宅を対象とした夏季の温熱環境調節に関する研究
    林 小 勇 , 梅宮 典子
    2016 年 81 巻 727 号 p. 785-794
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     Electricity shortages prevailed in many areas of Japan after the earthquake that occurred in Tohoku on March 11, 2011. Electricity conservation was requested by government in the national interest. Excessive air-conditioning and illumination were discouraged. In summer 2012, electric utility in Kansai asked businesses and households to reduce electricity consumption by up to 10 percent, and 9 percent was reduced in households.
     Survey on use of Air-Conditioners, electric fans and natural ventilation in summer was conducted in 2004 in southern Osaka city. Questionnaire sheets were distributed to 1,805 apartments; responded 257 of them by mail were analyzed. Another survey of the same items was conducted at the same 26 apartment buildings in the summer in 2011 when 1,765 sheets were delivered and responded 185 of them were analyzed. Weather conditions in summer in 2004 and 2011 were as normal as those of an average year.
     Most frequent setting temperatures were 27.0°C in 2004 and 27.5°C in 2011. However, the settings were 17.0°C to 29.0°C in 2004, and were 23.5°C to 30.0°C in 2011. The mean setting temperature was 26.0°C in 2004 and 27.5°C in 2011(p<.0001). These results demonstrate the success of the COOL-BIZ government campaign, which requested that cooling temperature settings be set at 28°C. Defining the cooling charge as the difference between May and August billing amounts, results show the following for 2011 compared to 2004. Electricity charges in August were 2, 413 yen (23.0%) lower. Electricity charges in May were 515 yen (8.8%) lower. Cooling charges were 2,051 yen (43.3%) lower. Also, differences in cooling charges per 1 degree difference of setting temperature were 595 yen in 2004 and 567 yen in 2011. Differences of regression estimates of cooling charges for mean setting temperatures between 2004 and 2011 were similar to differences of mean cooling charges between those of 2004 and of 2011.
     Comparison of 2011 data to 2004 data revealed that more respondents were satisfied with AC, orientation to AC use was higher, and awareness of cooling costs was lower. Residents depended more on AC to control indoor thermal conditions in 2011 than in 2004, and environmental consciousness was lower. Dissatisfaction with ‘high electric charge for cooling season’ decreased from 72.9% to 55.6%. The AC performance possibly improved during 2004‐2011.
     The cooling charge increased along with disturbances by solar radiation indoors in 2004, but no relation was found in 2011. The relation between the subjective degree of apartment ventilation and the degree of window opening was stronger both when asleep and when awake in 2004, but no relation was found in 2011.
     Respondents were less concerned about environmental issues and depended more on AC in 2011 than in 2004. Habits of controlling the indoor thermal environment according to the outdoor climate were not as strong in 2011. Most electricity conservation can be characterized as realized by higher AC temperature settings.
  • 尾関 義一, 中村 俊太, 尾方 壮行, 宮嶋 裕基, 鈴木 雅一, 田辺 新一
    2016 年 81 巻 727 号 p. 795-802
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     We have tried to predict thermal sensation by using of thermo-regulation model, but the prediction was limited to physiological response. PMV or SET* are used as method to predict thermal sensation, but these are applicable to only uniform thermal environment and not able to predict the thermal sensation in non-uninform thermal environments. Zhang proposed a predicting model for local thermal sensation, but the sensitivity of thermal sensation to the operative temperature is not examined.
     In this study we propose a new predicting model OTn based on Zhang model for local thermal sensation under non-uninform thermal environments.
     OTn model is proposed for the local thermal sensation with ASHRAE seven-point scale under non-uniform thermal environments. To develop the prediction model, the subject experiments in the climate chamber was conducted under the thermal conditions from cold side to hot side. The local thermal sensations to the operative temperature under steady states are predicted by the proposed model and original Zhang model respectively, and compared with the measured values. As a result of examinations, there were three issues.
     (1) Gap of set-point temperatures
     (2) The prediction trend is different according to the amount of clothing
     (3) Deterioration of prediction accuracy in high temperature condition
     Therefore it was necessary to introduce changing neutral skin temperature, supplementary skin temperature considered latent heat load and correction term considered the amount of clothing into Zhang model. So we added three improvements.
     (1) Changes to the set-point temperatures in which the amount of clothing and metabolic rate are considered.
     (2) Skin temperature is corrected by the latent heat load.
     (3) Addition of term where material and ventilation of clothes are considered
     It was found the accuracy of the predicted local thermal sensations in the hot environment using OTn model is much improved compared to the predicted value using Zhang model on the whole.
     To validate the new prediction model, it was tested with the Nilsson's subjective experimental results. The experiments were executed in a vehicle cabin and the environmental condition in summer and winter. To verify accuracy, we compared results of local thermal sensation and prediction result by the new model and Zhang model. The prediction accuracy on Head and under the hot environment were improved in particular compared with original Zhang model
     We developed OTn model which predicts the local thermal sensation with the use of the thermo-regulation model JOS-2. In developing OTn model, we incorporated the elements of the latent heat loss in the thermal sensation prediction equation, and the method of setting the set point temperature was changed. As a result, we confirmed that accuracy of prediction using OTn model has been improved compared to the previous model.
  • 高断熱化を図った体育館の断熱・気密性能の検証
    菊田 弘輝, 菊地 洋, 青柳 志歩, 羽山 広文
    2016 年 81 巻 727 号 p. 803-810
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     Immediately after the Great East Japan Earthquake, 622 school facilities were performing the function as evacuation shelters. However, the problems such as ensuring of power and water, shortage of heating equipment, and so on occurred. On the other hand, as an important measure against cold for disaster prevention in Sapporo, it has been stockpiling a lot of sleeping bag, blanket, portable kerosene stove. Moreover, an approach to high thermal insulation for gymnasiums was shown in June 2011, and it has actually been attempted from FY2014. The aim of this study is to quantitatively clarify the effects of building envelope performance improvement of gymnasium at Eco-Schools in cold regions designed by high thermal insulation that will contribute to improvement of thermal comfort, reduction of heating energy consumption and strengthening of disaster prevention. The results are as follows:
     1) Because eating and sleeping will be main actions at the time of emergency evacuation, there were the most 20 °C or more at the minimum room temperature that should be secured. In addition, the occurrence frequency of icicles was particularly high due to warm air retained near a ceiling and insufficient thermal insulation of a roof.
     2) Annual heating energy consumption per floor area in a gymnasium building was 344 MJ/m2/year that was equivalent to 2 times of that in a school building. About 80 % gymnasiums were widely distributed over 20-40 % regarding the heating consumption rate of gymnasium among entire school.
     3) There was no case that room temperature fell below 10 °C in gym H for high thermal insulation type designed by external insulation and SRC structure. Gym H had the superior temperature characteristics of minimum room temperature and room temperature fluctuation rate compared to gym I and A for old standard type. It was confirmed that gym H had the thermal insulation performance of more than twice of present standard specification.
     4) Inside-outside temperature difference based on solar heat in gym H was 11.4 °C on average. On the other hand, because it based on human body heat ensured by calorific value 34.56 kW from evacuees was 19.1 °C, it can be determined that the design target was almost achieved.
     5) The performance values of air leakage coefficient, air leakage exponent and effective leakage area were verified by airtightness measurement. It was considered that the difference of airtight performance was greatly influenced by the differences such as mainly structure type or window sash type.
     6) Equivalent leakage area including a confidence interval in gym H was 692-937 cm2, and also ACH50 was 0.41 h-1 (per envelope area 1.68 m3/h/m2). It was confirmed that infiltration heat loss was 5.5-22.1 kW under inside-outside temperature difference 20 °C and wind velocity 0-10 m/s.
  • 気象モデルと工学LESモデルのシームレスな結合手法の開発(その2)
    飯塚 悟, 玄 英 麗
    2016 年 81 巻 727 号 p. 811-817
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     For seamlessly merging mesoscale/regional meteorological models and engineering large eddy simulation (LES) models, the generation of appropriate velocity fluctuations at the inflow boundary (inflow turbulence) for engineering LES models has become a big issue. Generally, when coupling mesoscale/regional meteorological models and engineering LES models, the boundary conditions of engineering LES models are given based on the output results of mesoscale/regional meteorological models. However, due to the great difference in grid resolution between the two models, mesoscale/regional meteorological models cannot provide all the necessary boundary conditions for engineering LES models, especially inflow turbulence.
     The approaches to generating inflow turbulence can be divided into two types: (1) making use of separated or simultaneous preliminary simulations to provide the time-series data of velocity fluctuations to a primary computation and (2) artificially generating inflow turbulence data without flow simulations by making them satisfy various turbulence statistics.
     In our previous study (Kondo and Iizuka (2012)), an artificial generation method of inflow turbulence based on the Cholesky decomposition of the Reynolds stresses in the LES analysis of a plane boundary layer flow has been tested. The artificially generated inflow turbulence perfectly reproduced the targeted velocity and turbulent kinetic energy at the inflow boundary. However, the well-generated inflow turbulence was rapidly and unphysically attenuated when it flowed downstream. We concluded that this was mainly caused by the dissatisfaction of the governing equations, i.e., continuity and momentum equations.
     In this study, an approach to imposing the continuity condition on the artificially generated inflow turbulence was proposed and, in the LES analysis of a plane boundary layer flow, its effects were examined by comparing the results with those without the continuity condition and using periodic inlet-outlet boundary condition. As a result, the attenuation of the turbulent kinetic energy near the inflow boundary was slightly improved by imposing the continuity condition on the artificially generated inflow turbulence.
  • 隙間ネットワークを用いた室内濃度推移に関する数値実験
    林 基哉, 大澤 元毅, 本間 義規
    2016 年 81 巻 727 号 p. 819-826
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     The aim of this study is to clarify the influences of pollutants infiltration from concealed spaces upon indoor air quality in detached houses. The annual changes of pollutant concentrations were calculated using three leakage networks of wooden structures (A: a highly airtight wooden 2x4 stud structure, B: an airtight post-and-beam structure and C: a common post-and-beam structurer). The simulation program “Fresh” was used. The simulation program is based on three methods: a dynamic thermal calculation method using successive integration by Dr. Aratani, a calculation method of ventilation networks using Newmark-beta by Hayashi and Dr. Enai and a calculation method of pollutant concentrations using the ventilation networks by Hayashi. The annual changes of concentrations of pollutants which generate in the concealed spaces (beam spaces and a crawl space) in models with two ventilation systems (an exhaust ventilation system and an exhaust and supply ventilation system) are calculated using the weather data of Tokyo. These simulation results were compared with the measured infiltration ratios from concealed spaces.
     The results are the followings:
     1. The pollutants move upward by temperature difference and wind pressure and the pollutants infiltrate to the indoor spaces from the concealed spaces.
     2. The influence of leakage networks and ventilation systems upon the concentrations of pollutants which generate in the concealed spaces, is not similar to the influence upon those of CO2 and CO which generate in the indoor spaces.
     3. The indoor concentrations of pollutants from concealed spaces (beam spaces and a crawl space), are high in the case of the airtight houses (the equivalent leakage area: 2.8 cm2/m2) and the highly airtight houses (the equivalent leakage area: 0.3 cm2/m2), especially in those with exhaust ventilation systems.
     4. The similar characteristics of indoor decompression by ventilation systems and infiltration from concealed spaces are seen both in the simulation results and the measurement results.
     These results showed that it is necessary to prevent the pollutant infiltration from the concealed spaces according to the building standards on the sick house syndrome enforced in 2003. And the results showed that indoor air quality depends on the airtightness of houses and the decompression by ventilation systems. It is necessary to control air quality in the concealed spaces and to design ventilation networks in consideration of infiltration.
  • -2013年・大阪市内の観測を通して-
    橋本 侑樹, 鍋島 美奈子, 重田 祥範, 亀卦川 幸浩, 井原 智彦
    2016 年 81 巻 727 号 p. 827-834
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     The urban heat island (UHI) phenomenon has been more accelerated and the outdoor air temperature (OT) has become higher. Such OT rise is posing an increase in electricity consumption (EC) for air conditioning. Nowadays, the UHI countermeasure such as green roofs is developed and installed in order to decrease OT and reduce energy consumption for air conditioning. However, the countermeasure can bring adverse effects on the society. For example, green roof increases outdoor air humidity. It can increase EC for air conditioning through lowered efficiency of air conditioners due to dew condensation. Therefore, we need to understand a quantitative relationship between the energy consumption and the meteorological elements such as OT and air humidity throughout the year for reasonable installation of the UHI countermeasures. Thus, we aimed at quantifying sensitivities of EC to meteorological elements in city-block scale, which are residential and business districts. Moreover, we compare previous studies which analyzed sensitivities of EC to OT before the Grate East Japan Earthquake because some studies reported the relationship between EC and OT was changed due to this earthquake.
     Two apartment residential, one detached residential, and two business districts in Osaka city, which is the second largest city of Japan, were chosen as the target districts in this study. The district sizes are 1 to 3 km2. We installed meteorological instruments to the rooftops of five primary schools in the five target district so that we measured the meteorological data which are OT, and relative humidity from April 2013 to March 2014. We also obtained hourly electricity consumption data in the target districts. Then, we calculated the sensitivities of EC to OT and specific humidity (SH) using the multiple regression (hockey stick regression) analysis. We analyzed branch points and sensitivities of summer OT and SH during only summer.
     Our analysis showed that the branch points of summer OT in the business districts were 7°C lower than those in the residential districts. It is suggested that occupants and appliances in the business districts lead to the air conditioning demand. The branch points of winter OT in the business district were similar to that in the residential districts. In the residential districts, the sensitivities of EC to summer OT in early morning is the smallest and that at night is the largest during a day. The sensitivities of summer SH were the similar tendency of those of summer OT because dehumidification on the fan coils in the air conditioner occurs and leads to EC.
     We compared our results with the previous studies' results before the Great East Japan Earthquake (March 11, 2011). Sensitivities of EC to winter OT in our result were similar to those in the previous studies, however, those to summer OT in our analysis were 50-60% smaller than those in the previous studies. People is considered to conserve electricity in summer by not introduction of energy-saving appliances but change in their behaviors.
  • -建物内放射線量の簡易計算法(その1)-
    大森 敏明, 加藤 信介, 金 敏 植 , 糠塚 重裕
    2016 年 81 巻 727 号 p. 835-843
    発行日: 2016年
    公開日: 2016/09/30
    ジャーナル フリー
     Large amounts of fission products (FP) were released at the Fukushima Daiichi Nuclear Power Plant of Tokyo Electricity Power Company due to the accident, initiated by the tsunami that was triggered by the East Japan Great Earthquake on March 11, 2011. It has been more than five years since the disaster occurred. The radioactivity owing to FP deposited on the grounds, houses, forests and so on have been decreasing steadily by the decay of FP, soil infiltration, weathering effect and the planned decontamination. As a result, the residence restriction areas have been re-organized as areas prepared for evacuation cancellation and it has been allowed for the residents to return to their homes. The conscious surveys for residents showed that they were worrying about the influence of radioactivity to human body. Therefore, it is necessary to let them know sufficient detailed information and knowledge. The decrease of radiation dose depends considerably on the density of the building construction materials, so that it would be desirable for indoor radiation dose rate to be estimated by taking account of housing types and floor plans.
     This paper deals with a novel method for calculating radiation dose rate within a building and around its surroundings. We employed the Monte Carlo method to calculate gamma ray penetration through various shield configurations and the absorption within an object positioned at an evaluation point. The gamma rays shifted to lower energy levels caused by the Compton scattering, i.e. buildup fluxes, were simply treated using the buildup factor as a function of the mean free path of photons.
     RADAR-γ code which has been developed on the basis of this study was benchmarked for a simplified geometry case with Cesium 137 deposited on the ground surface. The results were compared with the point-kernel integration code QAD-CGGP-A, which has been widely used in radiative physics analyses to calculate operational exposures and gamma radiation fields through shielding. The results of both methods were in good agreement. It was confirmed that the proposed method could be used for predicting radiation dose rate in the area where FP have been deposited.
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