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131.
Urban green spaces offer multiple ecosystem services (ES), which provide a variety of benefits to human well-being. Yet in urban planning they are not taken into account systematically. Recently new tools have been developed integrating ES into procedural modeling and visualization to raise stakeholder awareness for the explicit ES trade-offs that have to be made. These tools yet do not allow fast and comprehensive integration of ES provision in urban environments. In this paper we show how urban green space typologies can be linked to ES provision for facilitating collaboration between stakeholders of different backgrounds. Based on a generic typology green spaces were mapped and linked with information on potentially provided ES and their parameters. Further, pattern designs of the green space types were described with a form-based code. Both the map of green space types and the pattern designs were integrated into the parametric modeling and visualization chain of Esri CityEngine resulting in 3D visualizations of the green space patterns and correlating ES indicators. The green space typology allows for integrating different kinds of knowledge from both science and practice communities. The procedural model enables rapid interactive visualization of urban patterns and calculation of simple indicator values on the provision of ES. The simple approach for mapping green space types with low data requirements and the generic green space design patterns allow for transferability to other places and application to large areas. The developed approach is simple and fast yet comprehensive to communicate the vital importance of all green space types within the urban environment. 相似文献
132.
In 2014, a cloudburst hit Malmö City and parts of the city were severely flooded. In this study, we assess the possibility to forecast this event by high-resolution ensemble rainfall-runoff modelling. Meteorological reforecasts are generated by the convection-permitting HarmonEPS model and the hydrological response is simulated by the HYPE model. Although the meteorological forecasts manage to reproduce the observed extreme rainfall intensities, due to location errors only a weak, low-probability signal of a high runoff in Malmö City is obtained in direct forecasts. To describe and visualize the spatial uncertainty of local rainfall extremes in forecasts, and construct hydrological model forcing representing “worst-case ensembles”, an approach called Distance-Dependent Depth-Duration in Forecasts (4DF) is proposed. In this approach, a depth-duration analysis is combined with a neighborhood approach to describe rainfall severity as a function of distance from the basin. The results demonstrated the applicability of the approach for improved situation awareness. 相似文献
133.
《Energy Policy》2013
Using 1997 personal trip survey (PTS) data in the Kumamoto metropolitan area, this paper examined the influence of urban form on energy consumption through an energy estimation model from a microeconomic perspective. As all goods and service are assumed to satisfy the need of people, we estimated the individual energy consumption based on the demand of goods, which is explained by a utility maximization problem constrained by income. 52.84 GJ of energy is estimated for one person one year in Kumamoto metropolitan area. 19.57% of energy is used for mobility goods. A spatial regression was performed to analyze the relationship between energy efficiency and urban form characteristics in terms of density, diversity, and accessibility. The results of regression analysis show that employment density, ratio of employee in retail department, transit fare, and distance to city center are the most influential factors of energy efficiency. Findings suggest compact development and integrated policies for increasing employment density, especially, employment proportion of local residents are suggested. Moreover, measures to improve the attractiveness of mass transit should be encouraged to increase energy efficiency in Kumamoto. 相似文献
134.
M. Shahadat Hossain Sayedur Rahman Chowdhury Nani Gopal Das S.M. Sharifuzzaman Abida Sultana 《Landscape and urban planning》2009,90(3-4):119-133
Site selection is a key factor in any aquaculture operation, affecting both success and sustainability as well as solving land or water use conflicts. This study was conducted to identify suitable sites for carp farming development in urban water bodies (UWBs) of Chittagong, Bangladesh using Geographical Information Systems (GIS) based MultiCriteria Evaluation (MCE) of water, soil and infrastructure database. ASTER imagery and 14 thematic layers were analyzed with ENVI and GIS capabilities, and developed a series of GIS models to identify and prioritize the appropriate UWBs for carp farming. The study identified 487 UWBs occupying 362 ha and revealed 280 ha (77%) is the most suitable, 36 ha (10%) is moderately suitable and 46 ha (13%) is not suitable which was consistent with field verification. The results are encouraging for extension of carp culture and diversify the economic activities of the urban dwellers. 相似文献
135.
A wind-tunnel study of flow distortion at a meteorological sensor on top of the BT Tower, London, UK
Janet F. Barlow James HarrisonAlan G. Robins Curtis R. Wood 《Journal of Wind Engineering & Industrial Aerodynamics》2011,99(9):899-907
High quality wind measurements in cities are needed for numerous applications including wind engineering. Such data-sets are rare and measurement platforms may not be optimal for meteorological observations. Two years' wind data were collected on the BT Tower, London, UK, showing an upward deflection on average for all wind directions. Wind tunnel simulations were performed to investigate flow distortion around two scale models of the Tower. Using a 1:160 scale model it was shown that the Tower causes a small deflection (ca. 0.5°) compared to the lattice on top on which the instruments were placed (ca. 0-4°). These deflections may have been underestimated due to wind tunnel blockage. Using a 1:40 model, the observed flow pattern was consistent with streamwise vortex pairs shed from the upstream lattice edge. Correction factors were derived for different wind directions and reduced deflection in the full-scale data-set by <3°. Instrumental tilt caused a sinusoidal variation in deflection of ca. 2°. The residual deflection (ca. 3°) was attributed to the Tower itself. Correction of the wind-speeds was small (average 1%) therefore it was deduced that flow distortion does not significantly affect the measured wind-speeds and the wind climate statistics are reliable. 相似文献
136.
Sketchup软件作为一款功能强大的3D设计软件,在城市景观深化设计中有着诸多应用优势,可充分表达创作者设计理念,完成与客户的实时交流,方便进行详细的细节推演,有利于空间的意象塑造,可通过深入对比材质肌理达到最佳景观效果。本文介绍了Sketchup软件在城市景观设计中的三大深化运用效果,并对其应用的策略和方法进行了探究,希望能为城市景观设计提供参考。 相似文献
137.
Objective
Describe age-based urban pedestrian versus auto crash characteristics and identify crash characteristics associated with injury severity.Materials and methods
Secondary analysis of the 2004–2010 National Highway and Traffic Safety Administration database for Illinois. All persons in Chicago crashes with age data who were listed as pedestrians (n = 7175 child age ≤19 yo, n = 16,398 adult age ≥20 yo) were included. Incidence and crash characteristics were analyzed by age groups and year. Main outcome measures were incidence, crash setting, and injury severity. Multivariate logistic regression analysis was performed to estimate injury severity by crash characteristics.Results
Overall incidence was higher for child (146.6 per 100,000) versus adult (117.3 per 100,000) pedestrians but case fatality rate was lower (0.7% for children, 1.7% for adults). Child but not adult pedestrian injury incidence declined over time (trend test p < 0.0001 for <5 yo, 5–9 yo, and 10–14 yo; p < 0.05 for 15–19 yo, p = 0.96 for ≥20 yo). Most crashes for both children and adults took place during optimal driving conditions. Injuries were more frequent during warmer months for younger age groups compared to older (χ2p < 0.001). Midblock crashes increased as age decreased (p < 0.0001 for trend). Most crashes occurred at sites with sub-optimal traffic controls but varied by age (p < 0.0001 for trend). Crashes were more likely to be during daylight on dry roads in clear weather conditions for younger age groups compared to older (χ2p < 0.001). Daylight was associated with less severe injury (child OR 0.93, 95% CI 0.87–0.98; adult OR 0.90, 95% CI 0.87–0.93).Conclusion
The incidence of urban pedestrian crashes declined over time for child subgroups but not for adults. The setting of pedestrian crashes in Chicago today varies by age but is similar to that seen in other urban locales previously. Injuries for all age groups tend to be less severe during daylight conditions. Age-based prevention efforts may prove beneficial. 相似文献138.
Footpaths provide an integral component of our urban environments and have the potential to act as safe places for people and the focus for community life. Despite this, the approach to designing footpaths that are safe while providing this sense of place often occurs in silos. There is often very little consideration given to how designing for sense of place impacts safety and vice versa. The aim of this study was to use a systems analysis and design framework to develop a design template for an ‘ideal’ footpath system that embodies both safety and sense of place. This was achieved through using the first phase of the Cognitive Work Analysis framework, Work Domain Analysis, to specify a model of footpaths as safe places for pedestrians. This model was subsequently used to assess two existing footpath environments to determine the extent to which they meet the design requirements specified. The findings show instances where the existing footpaths both meet and fail to meet the design requirements specified. Through utilising a systems approach for footpaths, this paper has provided a novel design template that can inform new footpath design efforts or be used to evaluate the extent to which existing footpaths achieve their safety and sense of place requirements. 相似文献
139.
140.
我国正迈入快速城市化建设过程中,运用GIS技术手段来解决城市规划过程中的城市化建设进程信息整合管理,对于提高城市规划信息整合效率、避免重复建设、重叠规划、一库多建等城市规划问题有着积极意义。 相似文献