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11.
本文以长沙黄兴南路步行街为调查研究对象,采用现场行为观察法和抽样调查法,从环境行为学、环境心理学的角度分析步行街外部环境,通过评估使用者对公园的满意程度和主要行为特点,从而探索城市商业步行街设计的外部环境评价标准。 相似文献
12.
Mapping of background air pollution at a fine spatial scale across the European Union 总被引:5,自引:0,他引:5
Rob Beelen Gerard Hoek Danielle Vienneau David J. Briggs 《The Science of the total environment》2009,407(6):1852-1867
Background
There is a need to understand much more about the geographic variation of air pollutants. This requires the ability to extrapolate from monitoring stations to unsampled locations. The aim was to assess methods to develop accurate and high resolution maps of background air pollution across the EU.Methods
We compared the validity of ordinary kriging, universal kriging and regression mapping in developing EU-wide maps of air pollution on a 1 × 1 km resolution. Predictions were made for the year 2001 for nitrogen dioxide (NO2), fine particles < 10 µm (PM10), ozone (O3), sulphur dioxide (SO2) and carbon monoxide (CO) using routine monitoring data in Airbase. Predictor variables from EU-wide databases were land use, road traffic, population density, meteorology, altitude, topography and distance to sea. Models were developed for the global, rural and urban scale separately. The best method to model concentrations was selected on the basis of predefined performance measures (R2, Root Mean Square Error (RMSE)).Results
For NO2, PM10 and O3 universal kriging performed better than regression mapping and ordinary kriging. Validation of the final universal kriging estimates with results from all validation sites gave R2-values and RMSE-values of 0.61 and 6.73 µg/m3 for NO2; 0.45 and 5.19 µg/m3 for PM10; and 0.70 and 7.69 µg/m3 for O3. For SO2 and CO none of the three methods was able to provide a satisfactory prediction.Conclusion
Reasonable prediction models were developed for NO2, PM10 and O3 on an EU-wide scale. Our study illustrates that it is possible to develop detailed maps of background air pollution using EU-wide databases. 相似文献13.
鉴于历史地图自身信息的模糊性,采用历史地图解译法对桂湖水系相关的历史地图进行解译绘制,通过解译图纸能较为清楚展示桂湖水系的演变过程,进而相对客观地总结其水系的演变特点。从城市水系与园林水源、水系周边建筑营建、水系空间形态划分3个方面,按照隋唐、宋代、明清、近代、现代的时间段对桂湖水系的演变过程进行梳理,并从新都城市水系与桂湖园林水系的关系、水系周边建筑功能及附属空间属性的变化、水系形态的艺术划分3方面归纳总结水系演变特点: 1)新都城市水系与桂湖园林水系在形态结构联系上呈现出完整、完善、破坏、重建4个阶段,桂湖园林水系与新都城市水系在水系体系构成上经历融合、维持、撤离、融入4个阶段的变化。2)水系周边建筑功能经纪念性萌芽、公共性增强、纪念性强化、纪念性精炼的变化,其建筑附属空间布局经历游赏性空间错列分布、公共性空间沿岸排布、纪念性空间中心贯穿、纪念性空间核心主导的4个阶段,使得桂湖从以游玩聚会为主的驿站园林变为以纪念为主的公共园林。3)桂湖水系的形态结构划分呈一池三岛“粗”分、五岛两堤“概”分、五岛两堤“密”分与五岛两堤“旷”分的演变特点。 相似文献
14.
利用Gleeble3500热模拟机对25Cr Mo钢进行热压缩试验,研究变形温度为950~1 100℃、应变速率为0.01~10 s-1条件下的应力-应变曲线。根据动态材料模型DMM建立材料的热加工图,确定其热变形的流变失稳区,得到25Cr Mo钢在试验参数范围内的最佳热变形工艺参数:温度为1 050~1 100℃、应变速率为0.1 s-1。 相似文献
15.
Michael Lanahan Sarah Engert Taewoo Kim 《Journal of Building Performance Simulation》2019,12(1):68-81
Buildings feature a prominent role in electric grid loading, as they use about 75% of the total electricity generated in the United States and are main drivers of electric peak demand in the summer due to electrically driven air conditioning systems. Energy storage is a key technology that can increase energy cost savings, and add flexibility to the grid. However, cost is an important factor to consider. This study proposes a rapid approach that allows for visualization of potential cost savings by introducing energy storage as a peak load control for residential buildings in California. A combination of EnergyPlus load data generation, Matlab post-processing, and Google Fusion Tables data presentation analyses the potential cost savings when energy storage is implemented and TOU rates are applied. The study presents potential annual cost savings of $420 per home with storage capacities of 24?kWh. 相似文献
16.
Dragos Horvath Michael Lisurek Bernd Rupp Ronald Kühne Edgar Specker Jens von Kries Didier Rognan C. David Andersson Fredrik Almqvist Mikael Elofsson Per‐Anders Enqvist Anna‐Lena Gustavsson Nikita Remez Jordi Mestres Gilles Marcou Alexander Varnek Marcel Hibert Jordi Quintana Ronald Frank 《ChemMedChem》2014,9(10):2309-2326
This work describes a collaborative effort to define and apply a protocol for the rational selection of a general‐purpose screening library, to be used by the screening platforms affiliated with the EU‐OPENSCREEN initiative. It is designed as a standard source of compounds for primary screening against novel biological targets, at the request of research partners. Given the general nature of the potential applications of this compound collection, the focus of the selection strategy lies on ensuring chemical stability, absence of reactive compounds, screening‐compliant physicochemical properties, loose compliance to drug‐likeness criteria (as drug design is a major, but not exclusive application), and maximal diversity/coverage of chemical space, aimed at providing hits for a wide spectrum of drugable targets. Finally, practical availability/cost issues cannot be avoided. The main goal of this publication is to inform potential future users of this library about its conception, sources, and characteristics. The outline of the selection procedure, notably of the filtering rules designed by a large committee of European medicinal chemists and chemoinformaticians, may be of general methodological interest for the screening/medicinal chemistry community. The selection task of 200K molecules out of a pre‐filtered set of 1.4M candidates was shared by five independent European research groups, each picking a subset of 40K compounds according to their own in‐house methodology and expertise. An in‐depth analysis of chemical space coverage of the library serves not only to characterize the collection, but also to compare the various chemoinformatics‐driven selection procedures of maximal diversity sets. Compound selections contributed by various participating groups were mapped onto general‐purpose self‐organizing maps (SOMs) built on the basis of marketed drugs and bioactive reference molecules. In this way, the occupancy of chemical space by the EU‐OPENSCREEN library could be directly compared with distributions of known bioactives of various classes. This mapping highlights the relevance of the selection and shows how the consensus reached by merging the five different 40K selections contributes to achieve this relevance. The approach also allows one to readily identify subsets of target‐ or target‐class‐oriented compounds from the EU‐OPENSCREEN library to suit the needs of the diverse range of potential users. The final EU‐OPENSCREEN library, assembled by merging five independent selections of 40K compounds from various expert groups, represents an excellent example of a Europe‐wide collaborative effort toward the common objective of building best‐in‐class European open screening platforms. 相似文献
18.
《Education for Chemical Engineers》2014,9(1):e1-e14
In this work the usefulness of qualitatively studying and drawing three-dimensional temperature–composition diagrams for ternary systems is pointed out to understand and interpret the particular behavior of the liquid–vapour equilibrium of non-ideal ternary systems. Several examples have been used in order to highlight the interest and the possibilities of this tool, which should be an interesting support not only for lecturers, but also for researchers interested in experimental equilibrium data determination. 相似文献
19.
A method is proposed to be used as the first step in the ontology acquisition process. This method is based on the use of concept maps as a means of expression for the expert, followed by an application that assists the expert in detailing the structure of the knowledge represented in the map. This application analyses the concept map, taking into account the map topology and key words used by the expert. From this analysis a series of questions are presented to the expert that, when answered, reduce the map ambiguity and identify some common patterns in ontological representations, such as generalizations and mereologic relations. This information can be used by the knowledge engineer during further knowledge acquisition sessions or to direct the expert to a further improvement of the map. The method was tested by a group of volunteers, most of them engineers working at the aerospace sector, and the results suggest that both the use of concept mapping as well as the refining step are acceptable from the point of view of the end user, supporting the claim that this method is viable as an option to reduce some of the difficulties in large scale ontology construction. 相似文献
20.
《Journal of Location Based Services》2013,7(2):138-166
With the prevalence of mobile computing systems and location based services, large amounts of spatio-temporal data are nowadays being collected, representing the mobility of people performing various activities. However, despite the increasing interest in the exploration of these data, there are still open challenges in various application contexts, e.g. related to visualisation and human–computer interaction. In order to support the extraction of useful and relevant information from the spatio-temporal and the thematic properties associated with human trajectories, it is crucial to develop and study adequate interactive visualisation techniques. In addition to the properties of the visualisations themselves, it is important to take into consideration the types of information present within the data and, more importantly, the types of tasks that a user might need to consider in order to achieve a given goal. The understanding of these factors may, in turn, simplify the development and the assessment of a given interactive visualisation. In this paper, we present and analyse the most relevant concepts associated to these topics. In particular, our analysis addresses the main properties associated with (human) trajectory data, the main types of visualisation tasks/objectives that the users may require in order to analyse that data and the high-level classes of techniques for visualising trajectory data. In addition, this paper also presents an overview on a user study, conducted in function of this analysis, to compare two classes of visualisation techniques, namely static maps and space-time cubes, regarding their adequacy in helping users completing basic visualisation tasks. 相似文献