Assessing the oppressive impact of the form of tall buildings on citizens: Height,width, and height-to-width ratio

The tremendous growth in the development of tall buildings has necessitated assessment of their oppressive impact on citizens. Accordingly, this study seeks to assess the oppression caused by changes in the form of tall buildings (i.e. height, width, and height-to-width ratio) on observers at different distances. For this purpose, an assessment framework was developed based on the literature and examined through a case study with the results being compared with the criterion of permissible oppression (a visual weight of 8%) that can be endured by citizens. Finally, the accuracy of the results was evaluated by a survey of people's opinions.The findings indicated a relative correlation between the results of the framework and the participants' opinions, through there were some differences. Based on our survey, the effect of the building's height on oppression was generally more significant than that of the width. In scenarios where the height of the building was fixed, the width of 20 m was a critical point in oppression. If the building's width exceeded 20 m, the oppressive effect on citizens would significantly increase. Given a constant height, changing the height-to-width ratio from 2 to 3 was more effective in reducing oppression than altering it from 3 to 4.In conclusion, tall buildings with a height of 60 m or higher and a width of 15 m or higher on streets which are 30 m wide or narrower impose the highest oppression on the observer which can be mitigated with sufficient vegetation in front of the building.     

A Quantile Regression Approach to Evaluate Factors Influencing Residential Indoor Radon Concentration

Indoor radon concentrations depend on building characteristics such as building materials, ventilation and water supply. In this paper, a quantile regression approach is proposed to evaluate the effect of some buildings factors potentially influencing indoor radon concentration. Many of the considered factors, such as soil connection, age of construction and being a single family building, are found to have a statistically significant effect; however, this is far from being constant across the entire support of indoor radon concentration. A potential impact due to geological and geo-physical reasons is also found using the altitude of building locations as a surrogate variable. In addition, a clear local spatial effect is detected by a spatial autoregression approach.     

Dynamic global warming impact assessment integrating temporal variables: Application to a residential building in China

Climate warming is a global concern, and buildings have been recognized as a major contributor because the carbon emissions during their entire life cycles constitute a large share of the total value (almost 40% globally). Many life cycle assessments of buildings have been conducted to quantify the associated global warming impacts. However, few studies have considered the potential temporal variation over the long lifetimes of buildings. In this study, various temporal variables were combined to evaluate the dynamic life cycle global warming impact of a residential building in China. First, annual material and energy consumption data throughout the entire life cycle were acquired from questionnaire survey, statistical reports and literatures. Five dynamic variables (household size, usage behavior, replacement and improvement of components, waste treatment, and energy mix) and their effects on consumption levels were considered. Second, a dynamic inventory analysis tool (DyPLCA) was used to transform the temporal consumption data into dynamic greenhouse gas quantities. The global warming effects of these emissions were quantified using a dynamic characterization tool (DynCO₂). Finally, emission reduction targets for future decades were used to weight the severities of the impacts at different times. The dynamic instantaneous and cumulative global warming impacts of the building were calculated. Dynamic and static assessment results were compared. We also analyzed the contribution of each dynamic variable to the final results and found that the dynamic variables had very different effects (ranging from −42.00% to 45.34%). This study provided an operable dynamic assessment model and available dynamic data for the global warming impact assessment of buildings in China.     

Seasonal variation in ambient PM mass and number concentrations (case study: Tehran, Iran)

Tehran, the capital city of Iran, is an important industrial and commercial center. This city is one of the worst cities in the world in terms of air pollution, which is mostly due to mobile sources rather than stationary sources. Particulate matter (PM), which is a complex mixture of extremely small particles and liquid droplets, is considered as an important source of air pollution in Tehran. In this study, our objective was to study PM₁₀, PM_2.5, and PM_1.0 mass and number concentrations and find the correlations of these two parameters in the west-central parts of Tehran during two consecutive warm and cold seasons. The particles collected from five stations were analyzed for their mass and number simultaneously by a laser-based Grimm dust monitor. In general, it was found that the accumulation of the PM in this region is more in the cold season. PM₁₀ mass concentration increases almost twofold and PM_2.5 and PM_1.0 almost three times in this season. The mean number concentration of the particles (0.3–20 μm) was found to be almost 4.8 times in the cold season. It was also noticed that the average dimensions of the particles decrease in that season.     

Flow Field and Pollution Dispersion in a Central London Street

Urban pollution due to roadways is perceived as a major obstacle to implementing low-energy ventilation design strategies in urban non-domestic buildings. As part of a project to evaluate the use of a computational fluid flow model as an environmental design tool for urban buildings, this paper seeks to address the impact of pollution from roadways on buildings in areas of restricted topography and assess dominant influencing factors and other requirements for testing the flow model predictions. Vertical profiles of carbon monoxide (CO) and temperature at the facade of a building in a Central London street, in addition to above-roof wind speed and direction, were measured over a period of three months. The street has a height-to-width (h/W) ratio of 0.6 and is of asymmetric horizontal alignment. The air flows in the area surrounding the building were modelled using a computational fluid flow model for two orthogonal wind directions. CO concentrations were calculated from the steady-state flow field in order to place point measurements in the context of the flow field, identify persistent features in the measured data attributable to the flow structure and, by comparison with measurements, identify further testing requirements.Some qualitative and quantitative agreement between measured and modelled data was obtained. Measured CO levels at the building facade and vertical variations of CO were small, as predicted by the model. A wake-interference type flow was predicted by the model for wind speeds >2ms-1 with formation of a vortex cell occurring for roof-level wind speeds >5ms-1 for the cross-wind direction, which was reflected in the measured CO levels and facade gradients. A direction-dependent inverse relationship was noted, both in the model and measurements, between above-roof wind speed and facade CO levels although statistical correlations in the time series were poor. CO concentrations at the facade were found to increase with height frequently, as well as decrease, especially for parallel winds. It is expected that mechanical turbulence due to vehicles was largely responsible. In comparison, thermal stratification appeared to play only a minor role in controlling vertical mixing in the street, under low wind speed conditions.     

A case study on the historical peninsula of Istanbul based on three-dimensional modeling by using photogrammetry and terrestrial laser scanning

Terrestrial laser scanning is a popular methodology that is used frequently in the process of documenting historical buildings and cultural heritage. The historical peninsula region sprawls over an area of approximately 1,500 ha and is one of the main aggregate areas of the historical buildings in Istanbul. In this study, terrestrial laser scanning and close range photogrammetry techniques are integrated into each other to create a 3D city model of this part of Istanbul, including some of the buildings that represent the most brilliant areas of Byzantine and Ottoman Empires. Several terrestrial laser scanners with their different specifications were used to solve various geometric scanning problems for distinct areas of the subject city. Photogrammetric method was used for the documentation of the facades of these historical buildings for architectural purposes. This study differentiates itself from the similar ones by its application process that focuses on the geometry, the building texture, and density of the study area. Nowadays, the largest-scale studies among 3D modeling studies, in terms of the methodology of measurement, are urban modeling studies. Because of this large scale, the application of 3D urban modeling studies is executed in a gradual way. In this study, a modeling method based on the facades of the streets was used. In addition, the complimentary elements for the process of modeling were combined in several ways. A street model was presented as a sample, as being the subject of the applied study. In our application of 3D modeling, the modeling based on close range photogrammetry and the data of combined calibration with the data of terrestrial laser scanner were used in a compatible way. The final work was formed with the pedestal data for 3D visualization.     

The interaction between physical and social-psychological factors in indoor environmental health

Indoor environmental health is now recognized as an important factor in preventing respiratory health problems in the United States. It is also a concern in Canada due to the amount of time that Canadians spend indoors because of cold weather and the potential for increased time indoors during the summer if theclimate warms. The negative health effects are often labeled assick building syndrome, but diagnosing a building or itsoccupants as sick is complicated by the variety of symptoms, thepresence of chronic versus acute symptoms and social andpsychological (socio-psychological) factors that may reduce theeffectiveness of an engineering solution. As a case study, thecontribution of various factors to indoor environmental health,in three buildings at the University of Toronto, was examinedusing five different methods. The results indicate that theinhabitants of the buildings consider features other than airquality in considering building health such as design,maintenance, funding cuts and socio-psychological factors.     

Land mismatches,urban growth and spatial planning: A contribution to metropolitan sustainability

The unequal growth of population and buildings in metropolitan regions reflects dispersed urban expansion. This study illustrates an operational framework grounded on a diachronic analysis of urbanization processes in advanced economies that provides a comprehensive evaluation of the mismatch between resident population and building stock. Studying the urban cycle of a European city (Athens, Greece), a mismatch indicator was derived at the municipal level as the elasticity rate of resident population and total building stock changes over 7 time intervals between 1920 and 2010. Results indicate that divergences in population and building stock growth rates increased since the early 1980s. The population-buildings mismatch displays an increasingly asymmetric spatial distribution, evidencing more or less accelerated paths toward dispersed settlements that may outline unsustainable forms of land management. Municipalities with a compact morphology at the beginning of the study period showed a higher rate of self-contained urban expansion than municipalities with more dispersed settlements. A comparative analysis of the impact of town planning on enlarging population-settlement mismatches was finally proposed as a basic knowledge to sustainable land management in (rapidly expanding) metropolitan regions.     

Enhancing public building energy efficiency using the response surface method: An optimal design approach

Today, energy problems are becoming increasingly serious. The direct energy consumption of buildings accounts for 20% of the total energy consumption in a country. There are difficulties in continuing the mode of high energy consumption in the traditional construction industry. Therefore, the future of construction is in the development of green buildings. In the life cycle of a building, the consumption during the construction phase accounts for only approximately 20% of the total energy consumption. Most of the consumption occurs during buildings operations, such as lighting, heating, air conditioning and the running of various electrical appliances. Therefore, this paper focuses on the energy consumed during the building operation period with the aim of optimizing relevant design parameters to reduce total energy consumption. The West Twelfth Teaching Building (WTTB) of Huazhong University of Science & Technology (HUST) is used as a prototype, and Design Builder is used to establish a model of energy consumption and validate the reliability of the model based on the data obtained from the investigation. Based on this model, the study takes the perspective of energy conservation to analyze ten factors that may affect the energy consumption of the building: the heat transfer coefficient of the roof, the amount of fresh air, the heat transfer coefficient of interior walls, the heat transfer coefficient of the floors, the interior temperature, the energy efficiency ratio of the air conditioner, the thickness of the outer wall insulation, the ratio of windows to walls, the natural ventilation starting temperature and the solar heat gain coefficient of the outer windows. Those factors are then ranked according to their energy-saving potential through partial factorial design tests. The six factors with the most potential for energy savings are selected and divided into 2 groups to conduct a response surface optimization analysis of three factors at three levels. The best level of each factor and the optimal combination of all factors are obtained to reduce building energy consumption to the greatest possible extent and to provide a reference for teaching buildings and similar public buildings (PBs) in achieving the goal of “green building.”     

Monitoring of flow field based on stable isotope geochemical characteristics in deep groundwater

As circumstances of operating and maintenance activities for landfilling and composting in Tehran metropolis differ from those of cities in developed countries, it was concluded to have an environmental impact comparison between the current solid waste management (MSW) strategies: (1) landfill, and (2) composting plus landfill. Life cycle assessment (LCA) was used to compare these scenarios for MSW in Tehran, Iran. The Eco-Indicator 99 is applied as an impact assessment method considering surplus energy, climate change, acidification, respiratory effect, carcinogenesis, ecotoxicity and ozone layer depletion points of aspects. One ton of municipal solid waste of Tehran was selected as the functional unit. According to the comparisons, the composting plus landfill scenario causes less damage to human health in comparison to landfill scenario. However, its damages to both mineral and fossil resources as well as ecosystem quality are higher than the landfill scenario. Thus, the composting plus landfill scenario had a higher environmental impact than landfill scenario. However, an integrated waste management will ultimately be the most efficient approach in terms of both environmental and economic benefits. In this paper, a cost evaluation shows that the unit cost per ton of waste for the scenarios is 15.28 and 26.40 US$, respectively. Results show landfill scenario as the preferable option both in environmental and economic aspects for Tehran in the current situation.     

天津生态城低碳体验中心碳排放及减碳潜力研究

基于绿色建筑评价指标体系,采用eFootprint软件对天津市中新生态城低碳体验中心全生命周期碳排放量和运营阶段采用的主要绿色技术减碳潜力进行计算与分析,结果表明:该建筑运营阶段碳排放量占比最大,为89.74％,其次是物化阶段,为10.08％,废弃阶段仅占比0.18％.同时,太阳能热水技术措施的利用对建筑的减碳效果最好...     

Cumulative risk assessment for an urban agglomeration based on a relative risk model and multi-media fugacity model: A case study in Guangdong province,China

Urban agglomeration, which is an organism with distinct organizational characteristics, differs from a single city. In its policy-level environmental impact assessment, the ecological and health risks need to be addressed in a unified manner, because multiple cities interact and influence each other, and the environmental risks have multiple elements, multiple processes, and multiple effect interaction and superposition. To this end, this study proposed a regional-level cumulative risk assessment framework coupling a relative risk model (RRM) with a multi-media fugacity model (MFM). The RRM translated the risk causal relations into four city-differentiated matrices, which consisted of normalized factors (NFs), ranging from 0 to 1, that were indicative of the impact intensity and possibility. The MFM was embedded into the RRM to generate the NFs. The NFs were multiplied for each city-source-endpoint combination to get the overall risk score, and the score provided policy references. This framework was applied to Guangdong Province of China (GD). As heavy metal contamination is one of the GD's major concerns, this study analyzed their cumulative risks due to industrialization for the year 2020 and compared the city level and industrial level risk scores. The results showed that the central part of GD was under the highest risk, with Guangzhou, Foshan, and Jiangmen having the highest risk. From the perspective of the risk pressure sources, Pb and Cd were the biggest stressors. Non-ferrous/ferrous metals mining and processing and metal products manufacturing were the major threats. As these industries gain greater footholds in the GD's ecologically susceptible region, the relevant policies should be elaborately designed before new entrants commence their operations.     

Study of trace elements in wet atmospheric precipitation in Tehran,Iran

In this study, measurements of the trace metals Zn, Cd, Cr, Ni, Pb, Cu, Fe and Al were performed on 53 wet atmospheric precipitation samples (snow and rainwater) collected at a central site of Tehran. Samples were collected using a bulk sampler equipped with a high-density polyethylene funnel from November to May in 2011 and 2012 on the roof of a building in the city centre. Trace metals in the filtered samples were measured with ICP-MS. Statistical analysis of the results revealed that Al, which is principally a crustal-derived element, was the highest mean measured concentration. The pH ranged from 4.2 to 7.1 with a mean value of 5.1. Crustal enrichment factors (EF_c) related to the relative abundance of elements in crustal material was calculated using Al as reference crustal. EF_c calculations indicated that samples were not enriched with Fe and Cr but were, fairly to extremely, enriched with Zn, Cd, Ni, Pb and Cu. Factor component analysis with varimax-normalized rotation was conducted to find the probable sources of the measured species. This resulted in two factors with eigenvalues greater than unity. Factor 1 showed an anthropogenic source, mostly industrial combustion and local traffic emissions, for Zn, Cd, Ni, Pb, and Cu while factor 2 showed a crustal contribution for Al, Fe and Cr.     

重庆市住宅楼环境电磁辐射的初步测量与分析

初步探测重庆市住宅楼环境电磁辐射的现状及其影响因素,为建立人居环境电磁场特征数据库提供依据。按照国家标准的要求和方法,在重庆市选择4个典型居住小区,分别测量各小区住宅楼不同楼层电梯门口或楼梯间以及各住宅楼楼顶的电磁辐射水平,结果表明,本次横断面调查中,在1MHz～40GHz频段,各栋楼的综合场强为17.13～17.18V/m,已接近GB 8702-88《电磁辐射防护规定》的公众照射导出限值,各楼层间差异无统计学意义(P>0.05)。在5～1000Hz频段,各栋楼楼内综合场强分布差异无统计学意义(P>0.05),而临近高压线的住宅楼楼顶综合场强明显高于其他小区楼顶以及同一栋楼其他楼层的综合场强(P<0.05),并且该楼各楼层的磁场强度明显高于其他住宅楼(P<0.05)。所测住宅楼的环境电磁辐射水平未超出国家相应标准限制,不同楼层电磁辐射水平与极低频辐射源的分布有关。     

Assessment Of Trampling Simulation Impacts On Native Vegetation In Mediterranean Sclerophyllous Forest

This study examines the effects of visitors on vegetation of natural semi-arid areas of Mediterranean basin using controlled experimental trampling. Impacts were assessed on days 1, 5, 15 and 30 examining presence of plant species, their cover and height in linear transects suffering a constant trampling intensity (25, 75, 100 and 200 passes/day). In addition, the study included the analysis of factors such as plant species, trampling intensity, the cumulative impact (day effect) and the type of footwear on plant variables. The results showed a decrease on plant cover and height influenced by cumulative (day) effect, an effect of trampling intensity and a different effect for each species. In contrast, shoe type affected only slightly the decrease in plant height. The evolution of plant cover revealed which species were most resistant to trampling. The disappearance of plant individuals during trampling appeared to be an impact index better than plant cover, because cover increased in some species when they were trampled thus introducing a bias.     

北京市高架道、桥交通噪声状况调查与对策研究

对北京市区内８１座道路立交桥和１１段高架道路的声环境状况进行了多方位的调研与实测。分析了高架道、桥附近声环境的地面水平分布特征、高层楼房垂直分布特征、昼夜时间分布特征及产生的原因。从增强城市总体规划与交通管理，注意沿街建筑功能配置与布局，加强临街住户门窗隔声效果，适当建设有效的道路隔声屏障等方面提出了城市发展中解决和控制交通噪声污染的对策建议。     

Analysis and assessment of ground-level ozone measured at two stations in Tehran

In this study, variations of ambient ozone level are thoroughly analysed according to the monitored data in a mixed residential, commercial and industrial city, Tehran, based on considering the meteorological factors. Ozone as a pollutant shows typical annual, weekly and diurnal cycles. This analysis has shown that the ozone level concentrations were below the WHO guidelines in Tehran during 2000–2003. The relation between ozone level at two different stations (Aghdasieh and Fatemi) is found (r?=?0.51). The ozone level response to meteorological parameters is investigated. The results suggest that the ozone level is affected (positively or negatively) by meteorological conditions, e.g. relative humidity, solar radiation, air temperature, wind speed and wind direction.     

The changes of densities and patterns of roads and rural buildings: a case study on Dongzhi Yuan of the Loess Plateau, China

Roads and buildings are considered as primary causes of rural landscape changes. In this study, linear regression models were used to analyze the dynamic influences of environmental factors and variables on roads and rural buildings from 1979 to 2005 in Dongzhi Yuan (tableland) of the Loess Plateau, China. The relationship between roads and rural buildings and their effects on Dongzhi Yuan are discussed also. The results showed that three environmental factors (topography, land cover, and development level) explained roads better than rural buildings referring densities and patterns. The environmental variables significantly related to roads have decreased, whereas those related to rural buildings have increased over time. Among these significant variables, percent of farmland mostly determined the densities and patterns of both roads and rural buildings. There was significant correlation between roads and rural buildings in terms of density and pattern. In addition, roads and rural buildings have increased greatly in gully areas of this region. Therefore, more attention should be paid to planning of roads and rural buildings in Dongzhi Yuan.     

Improving the living environment of Singapore

For the past quarter century, the government of Singapore has redeveloped the city with multiple objectives. The city should be free of squatters, slums and pollutive influences. It should be clean, green and healthy for living. All necessary infrastructures are provided and function well. All the necessary building floor spaces are available to facilitate the daily needs of the people and to enhance economic growth.While all of these objectives should be kept and augmented, the city must now update its position and even give added attention to the quality of the living environment, visual and otherwise, in order to make Singapore a tropical city of excellence. This paper attempts to review the past achievements and outline the approaches envisaged for the near future.Plenary speaker.     

Developing an automated BIM-based life cycle assessment approach for modularly designed high-rise buildings

Modular construction has attracted increasing attention due to its energy and environmental benefits. Digital technologies such as building information modelling (BIM) have also been explored to generate and manage data through the lifecycle of buildings. Although research has been performed in the area of integrating BIM and modular construction, BIM-based automated lifecycle assessment (LCA) of prefabricated buildings remains unexplored. This study therefore aims to develop a BIM-based LCA method for prefabricated buildings incorporating different assessment levels with unique system boundaries and functional units. The developed approach can support automated assessments through all lifecycle phases of a prefabricated building. It is achieved through an automated process of creating parameters to merge LCA data into the building model, systematic zoning, model setup and impact estimation. This approach is applied to evaluate the energy and environmental performances of a case building in Hong Kong. The case study validated the efficiency of the developed BIM-based LCA method in providing a systematic and detailed assessment of modularly designed buildings. This study extends the knowledge in automated BIM-based LCA by addressing specific characteristics of prefabrication and promotes the incorporation of comprehensive and detailed LCA data into BIM models for improved design robustness and holistic performances of buildings. This validated approach will enhance the willingness of designers to apply LCA during the design stages for minimizing the energy and environmental impacts of both new and renovated buildings with prefabrication.