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1.
各种设备设施的制造及应用给人们的日常生活带来了便利,体现了人类社会文明的进步,但是这些设备设施运转时产生了大量的振动,给人们的正常生活带来了困扰。本文以北京某小区为例介绍了振源的辨识过程,并找出了住宅楼振动产生主因。  相似文献   

2.
Abstract Many factors affect the airflow patterns, contaminant removal efficiency and the indoor air quality at individual workstations in office buildings. The effects of office furniture design and workstation layouts on ventilation performance, contaminant removal efficiency and thermal comfort conditions at workstations were studied. The range of furniture configurations and environmental parameters investigated included: 1) partition heights, 2) partition gap size, 3) diffuser types, 4) supply air diffuser location relative to the workstation, 5) return air grill location relative to the workstation, 6) heat source locations, 7) presence of furniture, 8) supply air temperatures, 9) adjacent workstations, 10) contaminant source locations, 11) supply air flow rates, and 12) outdoor air flow rates. The tracer gas technique was used to study experimentally the relative impact of these parameters on the air distribution and ventilation performance, as well as contaminant removal efficiency. Thermal environmental parameters such as air velocity and temperature were monitored at several locations to characterize the impact of these parameters on the thermal comfort conditions. The results showed that the outdoor air flow rate had a significant influence on the mean age of air. The air distributions at all the workstations were good even when the supply air flow rate was relatively low (i.e 5 L/s). At the same time, most of the parameters tested had a significant influence on contaminant removal efficiency when there was a contaminant source present somewhere in the office.  相似文献   

3.
A number of measurements were made to help define the thermal and flow conditions in a 9 × 18 meter pool fire that was used to simulate a transportation accident. Temperatures were measured at twenty-eight locations throughout the continuous flame region. Velocities were measured at four vertical stations near the centerline of the pool. Heat fluxes were estimated from thermal measurements on and near vertical steel plates. As is often the case in fires of this size, the effects of mild, ambient winds on the measurements were pronounced. Attempts have been made to mitigate these effects by the application of conditional sampling. Temperatures and velocities are compared with other experimental results as well as results of modeling efforts.  相似文献   

4.
Indoor climate of two new blocks of flats was investigated. The case building was built for people with respiratory diseases by following the instructions of the Finnish Classification of Indoor Climate, Construction and Finishing Materials, while the control building was built using conventional building technology. The main indoor air parameters (temperature, relative humidity and levels of CO, CO2, ammonia, total volatile organic compounds, total suspended particles, fungal spores, bacteria and cat, dog and house dust mite allergens) were measured in six apartments of both the buildings on five occasions during the 3-year occupancy. In addition, a questionnaire to evaluate symptoms of the occupants and their satisfaction with their home environment was conducted in connection with indoor air quality (IAQ) measurements. The levels of indoor air pollutants in the case building were, in general, lower than those in the control building. In addition, the asthmatic occupants informed that their symptoms had decreased during the occupancy in the case building. This case study showed that high IAQ is possible to reach by careful design, proper materials and equipment and on high-quality construction with reasonable additional costs. In addition, the study indicated that good IAQ can also be maintained during the occupancy, if sufficient information on factors affecting IAQ and guidance on proper use and care of equipment are available for occupants.  相似文献   

5.
Previous studies have shown that building, social and personal factors can influence one’s perceived health and comfort. The aim of the underlying study was to get a better understanding of the relationships between these factors and perceived comfort. Self-administered questionnaires from 5732 respondents in 59 office buildings and building-specific data from the European Health Optimisation Protocol for Energy-efficient buildings (HOPE) study were used. Principal Component Analysis (PCA), reliability analyses, and linear regression analysis were performed. The outcome showed that perceived comfort is strongly influenced by several personal, social and building factors and that their relationships are complex. Results showed that perceived comfort is much more than the average of perceived indoor air quality, noise, lighting and thermal comfort responses. Perceived comfort is a phenomenon that deserves more research.  相似文献   

6.
Indoor air pollution in developing countries is a major global health problem, yet estimates of the global burden of disease vary widely and are associated with large uncertainty. The World Health Organization uses the fuel based approach to estimate 1.6 million premature deaths globally each year associated with exposure to indoor air pollution, of which 420 000 are in China. The fuel based approach uses a ventilation factor to account for differences in indoor air concentrations and exposures in different parts of the world based on regional differences in stove technology. In China this approach assumes that flues eliminate the majority of indoor air pollution, with a ventilation factor of 0.25. To account for historic exposure leading to current disease patterns the ventilation factor was adjusted to 0.5 for adult health endpoints. Measurements in three Chinese provinces, Shaanxi, Hubei and Zhejiang, however, show that high PM4 concentrations are present in kitchens and living rooms even with stoves with flues as a result of multiple stove and flue use. Comparison of Indian and Chinese indoor air concentrations suggests more appropriate ventilation factors in the range 0.76-1.0 for women and children, and 1.0 for men. Premature mortality in the three provinces using these estimates would be closer to 60 600, rather than current estimates of 46 000. With the addition of cardiovascular diseases these estimates would increase by 92 000. Pollutant based estimates using measured indoor air concentrations and combined with dose-response estimates would imply a burden of disease of 157 800 premature deaths including cardiovascular diseases, a tripling of current estimates.  相似文献   

7.
对于地板辐射供暖系统,建立数值计算的数学模型,应用有限元法得出一定表面温度均匀条件下的适宜的地板结构尺寸,可作为地板辐射供暖系统的设计依据。  相似文献   

8.
The 10 m diameter Dekani motorway tunnel was constructed using the principles of the NATM method. The tunnel was located in a flysch geological sequence, which was classified as heterogeneous weak rock. The aim of the research presented in this paper was to examine whether fibre reinforced shotcrete can be successfully used as the only material for the primary tunnel lining in these geological conditions. The interpretation of the interaction between the fibre reinforced shotcrete lining and the surrounding rock, which was based on monitoring in a 60 m long test section, is presented in the paper. The development of the new mix of steel and polypropylene fibres and shotcrete is described and the results of the laboratory testing of strength, stiffness and post-crack strength are presented. The success of the field test led to the use of the fibre reinforced shotcrete for the primary lining in a 410 m long section of the tunnel. Significant savings were made in the use of time and material without compromising the quality of the final product.  相似文献   

9.
Marina Lathouri provides a critical overview of the historiography of typology, tracing the word ‘type’ back to its 18th-century origins and through to its re-emergence as a standardised objet-type in the Modernist era. She closes by questioning the pertinence of type and typology today.  相似文献   

10.
The method of distributing the outdoor air in classrooms has a major impact on indoor air quality and thermal comfort of pupils. In a previous study, ([11] Karimipanah T, Sandberg M, Awbi HB. A comparative study of different air distribution systems in a classroom. In: Proceedings of Roomvent 2000, vol. II, Reading, UK, 2000. p. 1013–18; [13] Karimipanah T, Sandberg M, Awbi HB, Blomqvist C. Effectiveness of confluent jets ventilation system for classrooms. In: Idoor Air 2005, Beijing, China, 2005 (to be presented).) presented results for four and two types of air distribution systems tested in a purpose built classroom with simulated occupancy as well as computational fluid dynamics (CFD) modelling.  相似文献   

11.
A pilot study was performed to investigate whether the application of a new mechanical ventilation system with a fine F8 (MERV14) filter could improve indoor air quality in a high school near the Amsterdam ring road. PM10, PM2.5, and black carbon (BC) concentrations were measured continuously inside an occupied intervention classroom and outside the school during three sampling periods in the winter of 2013/2014. Initially, 3 weeks of baseline measurements were performed, with the existing ventilation system and normal ventilation habits. Next, an intervention study was performed. A new ventilation system was installed in the classroom, and measurements were performed during 8 school weeks, in alternating 2‐week periods with and without the filter in the ventilation system under otherwise identical ventilation conditions. Indoor/outdoor ratios measured during the weeks with filter were compared with those measured without filter to evaluate the ability of the F8 filter to improve indoor air quality. During teaching hours, the filter reduced BC exposure by, on average, 36%. For PM10 and PM2.5, a reduction of 34% and 30% was found, respectively. This implies that application of a fine filter can reduce the exposure of schoolchildren to traffic exhaust at hot spot locations by about one‐third.  相似文献   

12.
Abstract Fifty-nine houses in the small Canadian community of Wallaceburg, 39 with high levels of biologically active contaminants and 20 with low levels, were subjected to detailed field inspections: testing to determine house-operating parameters; monitoring of indoor environmental conditions; and simulating to predict the condensation formation potential under winter conditions. It was found that low air leakage and natural ventilation were not associated with higher levels of mold growth, as measured by ergosterol concentrations and airborne viable particulates. Analyses showed that moisture sources in the houses were a more significant factor in mold levels and dust mite antigen levels than relative humidity. Mold areas visible during inspection were not a good predictor of ergosterol concentrations in dust, indicating that much of the mold growth was in hidden locations.  相似文献   

13.
建筑业安全文化的内涵、表现、评价与建设   总被引:10,自引:0,他引:10  
本文从文化和安全的定义入手,结合建筑业的特点,讨论了建筑业安全文化的内涵.分析了施工企业的安全文化在企业、项目、项目中层管理者和工人四个层面上的特征和具体表现.讨论了安全文化和安全氛围这两个概念的区别和联系,对施工企业安全氛围的评价指标体系进行了归纳和分析.回顾了以往的施工企业安全氛围调查实践,并通过一个典型的案例,说明了安全文化与安全绩效的关系.最后,讨论了企业如何进行安全文化的建设、持续提高企业安全文化.  相似文献   

14.
Ventilation in the building is to assure a microclimate suitable for humans and animals as well as the durability of structures. Based on the data from literature theoretical heat and moisture balancing ventilation rate calculations for uninsulated cowshed are presented. At an indoor temperature of −6.7 °C and indoor–outdoor temperature difference of 1 °C, the theoretical ventilation rate of 2300 m3/h per cow is necessary to remove the water vapour produced by the cows from the building. At a difference of 2 °C the ventilation rate of 1200 m3/h per cow and at 5 °C 530 m3/h per cow is needed. But these calculated ventilation rates are probably unrealistic. Traditional methods are unreliable for uninsulated cowsheds and instead of that an alternative method for evaluating the ventilation rate is needed.  相似文献   

15.
Laboratory tests of particle removal were performed with a pair of carbon fiber ionizers installed upstream of a glass fiber air filter. For air flow face velocities of 0.4, 0.6, and 0.8 m/s, the overall particle removal efficiencies of the filter for all submicron particles were 17%, 16%, and 14%, respectively, when the ionizers were not turned on. These values increased to 27%, 23%, and 19%, respectively, when the ionizers were used to generate ions of 6.0 × 109 ions/cm3 in concentration. The carbon fiber ionizers were then installed in front of a glass fiber air filter located in a heating, ventilation, and air-conditioning (HVAC) system. Field tests were performed in a test office room with a total indoor particle concentration of 2.2 × 104 particles/cm3. When the flow rate was 75 cubic meters per hour (CMH), the steady-state values of the total indoor particle concentrations using the glass fiber air filter with and without ionizers decreased to 0.87 × 104 particles/cm3 and 1.15 × 104 particles/cm3, respectively, resulting in a 25% decrease of the ionizer effect. When the operation flow rate was increased to 115 and 150 CMH, the effect of the ionizer decreased to 19% and 17%, respectively. These experimental data match the results calculated using a mass-balance model whose parameters were determined from laboratory tests.  相似文献   

16.
Acute lower respiratory illnesses (ALRI) are the leading cause of death among children <5 years. Studies have found that biomass cooking fuels are an important risk factor for ALRI. However, few studies have evaluated the influence of natural household ventilation indicators on ALRI. The purpose of this study was to assess the association between cooking fuel, natural household ventilation, and ALRI. During October 17, 2004-September 30, 2005, children <5 years living in a low-income neighborhood of Dhaka, Bangladesh, were assessed weekly for ALRI and surveyed quarterly about biomass fuel use, electric fan ownership, and natural household ventilation (windows, ventilation grates, and presence of a gap between the wall and ceiling). Bivariate and multivariate analyses were performed using generalized estimating equations. Six thousand and seventy-nine children <5 years enrolled during the study period (99% participation) experienced 1291 ALRI. In the multivariate model, ≥2 windows [OR = 0.75, 95% CI = (0.58, 0.96)], ventilation grates [OR = 0.80, 95% CI = (0.65, 0.98)], and not owning an electric fan [OR = 1.50, 95% CI = (1.21, 1.88)] were associated with ALRI; gap presence and using biomass fuels were not associated with ALRI. Structural factors that might improve household air circulation and exchange were associated with decreased ALRI risk. Improved natural ventilation might reduce ALRI among children in low-income families. PRACTICAL IMPLICATIONS: The World Health Organization has stated that controlling pneumonia is a priority for achieving the fourth Millennium Development Goal, which calls for a two-third reduction in mortality of children <5 years old compared to the 1990 baseline. Our study represents an important finding of a modifiable risk factor that might decrease the burden of respiratory illness among children living in Bangladesh and other low-income settings similar to our study site. We found that the existence of at least two windows in the child's sleeping room was associated with a 25% decreased ALRI risk. Increasing available natural ventilation within the household in similar settings has the potential to reduce childhood mortality because of acute lower respiratory illnesses.  相似文献   

17.
François Roche of R&Sie(n) ruminates on the contradictory nature of the present: a time that is ‘vibrating’ while ultimately ‘lacking momentum’. Reclaiming ‘the scenarios and substances that condition architecture’, he rejects the large-scale flights of fancy of international signature architects and argues for the reactivation of ‘a throbbing, complex and unfinished “localism”’. In so doing, he advocates a machinism that enables fictionalisation and speculation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

18.
This study illustrates the utility of empirical and digital methodologies in examining the question to which degree an architect who lives and builds in one distinctive geographic and climatic region adapts his sacred architecture design to a different climatic region. Specifically, we analysed the thermal comfort in a Synagogue in Tel Aviv, Israel, designed by a renowned Swiss architect in 1996. The morphological analyses, actual measurements, and computerized energy simulations show that the synagogue exhibits high thermal discomfort during the hot-humid summers in Tel Aviv. The results of morphological analyses and simulations also show thermal discomfort in the synagogue during Tel Aviv's mild winters. When simulating the synagogue as if built in Switzerland, the results also show high thermal discomfort. Thus, the design of this synagogue did not necessarily consider climate conditions. However, the design does exhibit attentiveness and sensitivity to symbols and faith requirements.  相似文献   

19.
Zhang X  Zhao Z  Nordquist T  Norback D 《Indoor air》2011,21(6):462-471
There are few incidence studies on sick building syndrome (SBS). We studied two-year change of SBS in Chinese pupils in relation to parental asthma/allergy (heredity), own atopy, classroom temperature, relative humidity (RH), absolute humidity (AH), crowdedness, CO?, NO?, and SO?. A total of 1993 participated at baseline, and 1143 stayed in the same classrooms after two years. The prevalence of mucosal and general symptoms was 33% and 28% at baseline and increased during follow-up (P < 0.001). Twenty-seven percent reported at least one symptom improved when away from school. Heredity and own atopy were predictors of SBS at baseline and incidence of SBS. At baseline, SO? was associated with general symptoms (OR=1.10 per 100 μg/m3), mucosal symptoms (OR=1.12 per 100 μg/m3), and skin symptoms (OR=1.16 per 100 μg/m3). NO? was associated with mucosal symptoms (OR=1.13 per 10 μg/m3), and symptoms improved when away from school (OR=1.13 per 10 μg/m3). Temperature, RH, AH, and CO? were negatively associated with prevalence of SBS. Incidence or remission of SBS was not related to any exposure, except a negative association between SO? and new skin symptoms. In conclusion, heredity and atopy are related to incidence and prevalence of SBS, but the role of the measured exposures for SBS is more unclear. PRACTICAL IMPLICATIONS: We found high levels of CO? indicating inadequate ventilation and high levels of SO? and NO?, both indoors and outdoors. All schools had natural ventilation, only. Relying on window opening as a tool for ventilation in China is difficult because increased ventilation will decrease the level of CO? but increase the level of NO? and SO? indoors. Prevalence studies of sick building syndrome (SBS) might not be conclusive for causal relationships, and more longitudinal studies on SBS are needed both in China and other parts of the world. The concept of mechanical ventilation and air filtration should be introduced in the schools, and when planning new schools, locations close to heavily trafficked roads should be avoided.  相似文献   

20.
广东省标准DBJ 15-60-2008《建筑地基基础检测规范》提倡采用高应变法对预制管桩桩身完整性和单桩竖向抗压承载力进行验收检测,本文在论述高应变检测各种适用性的基础上,针对某工程进行动静对比试验,证明高应变检测应用于管桩完整性及承载力检测是科学和准确的,将其作为基桩验收的依据是值得推广的.  相似文献   

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