Preferences for and attitudes towards street flowers and trees in Sapporo, Japan

The benefits of street vegetation, in particular the importance of trees, for urban dwellers have been given wide attention. There is, however, a lack of research on flowers as an element of street vegetation. This paper explores preferences for various street-planting models, particularly those with different compositions of flowers, with or without trees. Eighty-one residents of Sapporo evaluated 59 photomontage simulations and answered a questionnaire concerning their attitudes to street flowers. Results revealed trees to be the factor with the greatest influence on preference. Among possible elements for the space beneath trees from a choice including soil, grass, hedge and flowers, flowers were the most favoured. In particular, low and ordered compositions of brightly coloured flowers were the most preferred. Tall flowers were not found to be either attractive or appropriate for streetscapes in this case study. A factor analysis of the variables related to attitudes towards street flowers revealed the following five factors: “psychological benefits and aesthetic value”, “natural–environmental”, “practical concerns”, “effort to maintain” and “non-aesthetic”. The highest rated items were all related to the aesthetic and psychological benefits of street flowers. Flowers were the most preferred element beneath street trees and were seen as not only contributing to the aesthetic quality of a street but as also having a positive influence on psychological well-being.     

Aerodynamic effects of trees on pollutant concentration in street canyons

This paper deals with aerodynamic effects of avenue-like tree planting on flow and traffic-originated pollutant dispersion in urban street canyons by means of wind tunnel experiments and numerical simulations. Several parameters affecting pedestrian level concentration are investigated, namely plant morphology, positioning and arrangement. We extend our previous work in this novel aspect of research to new configurations which comprise tree planting of different crown porosity and stand density, planted in two rows within a canyon of street width to building height ratio W/H = 2 with perpendicular approaching wind. Sulfur hexafluoride was used as tracer gas to model the traffic emissions. Complementary to wind tunnel experiments, 3D numerical simulations were performed with the Computational Fluid Dynamics (CFD) code FLUENT™ using a Reynolds Stress turbulence closure for flow and the advection-diffusion method for concentration calculations. In the presence of trees, both measurements and simulations showed considerable larger pollutant concentrations near the leeward wall and slightly lower concentrations near the windward wall in comparison with the tree-less case. Tree stand density and crown porosity were found to be of minor importance in affecting pollutant concentration. On the other hand, the analysis indicated that W/H is a more crucial parameter. The larger the value of W/H the smaller is the effect of trees on pedestrian level concentration regardless of tree morphology and arrangement. A preliminary analysis of approaching flow velocities showed that at low wind speed the effect of trees on concentrations is worst than at higher speed. The investigations carried out in this work allowed us to set up an appropriate CFD modelling methodology for the study of the aerodynamic effects of tree planting in street canyons. The results obtained can be used by city planners for the design of tree planting in the urban environment with regard to air quality issues.     

A new method for evaluating sulfur dioxide tolerance of certain trees

The paper proposes a new method for evaluating the tolerance of trees to SO₂ pollution stress, and grouping plants as indicators and controllers by tolerance index values. The index is calculated by a new arithmetic formula. The developed model is useful in identifying tolerant and susceptible plants to SO₂.     

A rating scale for housing-based health hazards

Objectives

This study investigated the validity and responsiveness of a rating scale designed to assess the housing-based hazards and their relationships to burden of disease symptoms in the building occupants.

Study design

A population-based cross-sectional survey.

Methods

Random-digit dialing with computer-assisted phone interviews was conducted to obtain information from 642 households in the City of Saginaw, Michigan about 71 housing-based hazards, symptoms of 43 diseases often associated with environmental exposures and demographic characteristics. The housing-based hazard index (HHI) was calculated from scores of hazards across the following eight dimensions: structural scale (18 items); moisture/mold scale (8 items), electrical scale (7 items), ventilation and combustion appliances scale (6 items); pest scale (6 items); pets scale (4 items), fire scale (6 items) and lifestyle-associated factors scale (12 items). Each item was assigned a relative score based on the likelihood that the housing occupants would be exposed to the hazard, the potential for serious health impacts, and the reported strength of its association with childhood lead poisoning and respiratory diseases. The psychometric properties of HHI and individual domains (scales) were assessed along with the associations between these indicators and the inventory of disease symptoms.

Results

The reliability of HHI was demonstrated by assessments of its dimensionality and internal consistency. Analysis of the predictive validity and responsiveness indicates that HHI and scores for most of the individual scales can discriminate between households in relation to the burden of reported disease symptoms.

Conclusions

The HHI represents a valid, reasonably reliable, and parsimonious measure of hazards that are congruent with the burden of symptoms generally associated with housing-related diseases.     

A fire danger rating system for Hawaii

Extremes in rainfall on the Hawaiian Islands make it difficult to judge forest fire danger conditions. The use of an automatic data collection and computer processing system helps to monitor the problem. Note: Messrs. Burgan and Fujioka are on the staff of the Pacific Southwest Forest and Range Experiment Station, Forest Service, U. S. Department of Agriculture. Mr. Hirata is with the National Weather Service. All three are stationed at Honolulu, Hawaii.     

A novel method to model trees for building daylighting simulation using hemispherical photography

The ability to simulate the effect of trees on natural light performance in buildings is contingent upon accurate simulation of light passing through the canopy. Accurate simulations require some assumption of leaf angle distribution (LAD) to compute canopy gap fractions. The ellipsoidal LAD can very closely approximate real plant canopies. The method requires calculation of leaf area density from observed distribution of gap fraction as a function of zenith angle. Two sets of Neem trees were studied (small and large). Hemispherical image acquisition and analysis for both groups was carried out to measure gap fractions. The results helped to develop a 3D tree model that was used to simulate the effect of tree interception of daylight. The illuminance levels were simulated under the tree model and the output results were validated against actual measurements using MBE and RMSE techniques (small trees: MBE = 0.33, RMSE = 0.20; large trees: MBE = 9.68, RMSE = 2.02).     

材料产烟毒性危险分级的动物试验方法

介绍了材料产烟毒性的评估方法及动物染毒试验方法原理和装置,对材料燃烧性能分级的毒性技术要求及判定进行阐述,指出了GB/T 20285-2006<材料产烟毒性危险分级>标准的重要作用.     

强度折减法在地下过街道稳定性分析中的应用

对有限元强度折减法在地下过街道稳定性分析中的应用进行了探讨,并模拟计算了在无支护、超前初次支护和二次衬砌条件下地道的开挖稳定安全系数,结果表明:无支护条件下,安全系数小于1.0,过街道不稳定;采取超前支护及加固措施后,安全系数大于1.0,但不满足规范要求;采用二次衬砌后,安全系数达到1.5,满足规范标准要求。     

Attitudes of residents of a medium sized town in South West Scotland to street trees

This paper considers the attitudes of residents, living in currently treeless streets in a Scottish town, to street trees. Tour streets were selected for the study to provide a gradation from underprivileged to affluent. Most respondents did not see trees as important in improving the quality of their street. Trees were seen as most important in the two affluent streets, and least important in a low income street with a preponderance of elderly residents. Male respondents were significantly more likely to favour street tree planting than females. Other factors investigated, such as respondent age, and the degree of maintenance care and structural complexity demonstrated by respondents' front gardens, did not show statistically significant associations with the expressed preference for street trees.     

依据城市自然条件和规划性质做好行道树树种规划

通过对海口市行道树现状的分析，提出依据城市自然条件和规划性质，按骨干树种、一般树种和试用树种进行树种规划的构思，同时对行道树树种选择和实施措施也作了一些探讨。     

城市街道空间活力的营造研究

随着城市建设的加快,导致城市活力的缺乏,对城市街道空间进行了分析,从街道空间的作用、问题和现状,探讨了如何创建充满活力的街道,提出了创建城市街道的方法,解决了城市街道空间活力的问题。     

最小二乘法在监测仪器检验率定中的应用

分析了最小二乘法的原理,探讨了岩土工程监测仪器检验与率定的目的和内容,对多点位移计的率定步骤和率定结果进行了分析,实际应用表明通过程序设计实现最小二乘法理论在监测仪器检验与率定工作中的应用是可行的。     

浅析街道景观照明设计

阐述了街道与景观照明的涵义,归纳了街道景观照明设计应注意的几个方面,分析了街道景观照明的影响因素,探讨了城市街道景观照明的设计原则,为城市景观照明设计提供依据,从而创造更人性化的街道夜景氛围。     

A rule-based weighted rating system forconcrete culverts

This paper demonstrates the use of a rule-based weighted rating system (RWRS) developed for improving the rating of concrete culverts. RWRS combines the qualitative rating based on a guideline commonly used by the Department of Transportation, the quantitative rating based on a regression model, and the inspector's own judgment on the culvert's rating. Weight on each rating is provided by the supervisor. A case study is presented to demonstrate the use of RWRS.     

Dispersion in a street canyon for a wind direction parallel to the street axis

We investigate pollutant dispersion in a street canyon for an external wind direction parallel to the street axis, a case which has been poorly documented in the literature. The study is performed numerically and analytically by means of a model based on a series of simplifying assumptions. The range of validity of these assumptions is discussed by comparing analytical and numerical results for two different street aspect ratios. Our results show that, for a critical length of the street, ground level concentration can be higher than those observed in a street canyon whose axis is perpendicular to the external wind direction. We show that this critical length depends on the street aspect ratio.     

城市街道家具表情初探

从感性和理性两个方面出发,对影响街道家具表情表达的特征因素进行了分析,提出了物态表情、情态表情、理性价值三个关于街具表情的概念并进行了阐述,对进一步研究街具总体表情类型奠定了基础。     

城市行道树选择规划初探

行道树是城市绿化的重要组成部分,对美化城市环境具有不可忽缺的作用。由于城市在选择行道树方面不够重视,导致行道树在城市绿化中不能充分显现景观效果。从目前城市行道树选择存在的问题入手进行分析,阐述了如何选择城市行道树的对策。     

关于创造有生命力的街道形态的研究

以太原市街道建设为例,对生命力要素和街道形态进行了论述,提出了创造具有生命力的街道形态理念,以期通过对创造有生命力的城市街道形态的研究,赋予街道新的有机生命力。     

混凝土构件试验回弹法检测及质量评定方法

主要阐述了回弹法的基本原理、对回弹仪的要求、检测方法、回弹值的计算、混凝土强度的计算和应注意的问题.     

A critical comparison of green building rating systems

Various green rating systems are established globally to evaluate the sustainability of construction projects. Their categories and criteria have been under constant updates to follow the sustainable trend of building development. This paper aims to develop a systematic review of the development of green rating systems. The specific objectives are: 1) discover how interest and research in green rating systems have developed; 2) identify the similarity,difference,strength and weakness of green rating systems;3) examine whether they fully assess the projects in all aspects of sustainability. Specifically,LEED( Leadership in Energy and Environmental Design),BREEAM( Building Research Establishment Assessment Method),CASBEE( Comprehensive Assessment Systemfor Building Environmental Efficiency) and Green Star NZ were analysed in this paper. The results indicate that BREEAM,LEED, and CASBEE have been utilized since late the 2000 s while Green Star NZ is still in its earlier stages. 70%of the research papers focusing on BREEAM,LEED,CASBEE are developed geographically in the USA,Canada, the UK,China, and Australia. Although these four rating systems were initiated in different contexts with different standards, Indoor Environment Quality,Energy,and Material are core common categories for all. Environmental concerns are the main focus in New Construction manuals while Society is emphasized in Neighbourhood Development manuals. Currently,BREEAM has been the only tool which could assess all four sustainable factors. Further in-depth research is anticipated to focus more on economic and institutional factors to improve the capability of green rating systems for sustainability assessment purposes.