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91.
《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
92.
《Energy Policy》2013
Household consumption requires energy to be used at all stages of the economic process, thereby directly and indirectly leading to environmental impacts across the entire production chain. The levels, structure and determinants of energy requirements of household consumption therefore constitute an important avenue of research. Incorporating the full upstream requirements into the analysis helps to avoid simplistic conclusions which would actually only imply shifts between consumption categories without taking the economy wide effects into account. This paper presents the investigation of the direct and indirect primary energy requirements of Australian households, contrasting urban, suburban and rural consumption patterns as well as inter- and intra-regional levels of inequality in energy requirements. Furthermore the spatial and socio-economic drivers of energy consumption for different categories of energy requirements are identified and quantified. Conclusions regarding the relationships between energy requirements, household characteristics, urban form and urbanization processes are drawn and the respective policy implications are explored. 相似文献
93.
Solar radiation is a key factor determining electricity produced by photovoltaic (PV) systems. This paper presents a solar radiation database of Europe developed in the geographical information system, and three interactive web applications providing an access to it. The database includes monthly and yearly average values of the global irradiation on horizontal and inclined surfaces, as well as climatic parameters needed for an assessment of the potential PV electricity generation (Linke atmospheric turbidity, the ratio of diffuse to global irradiation, an optimum inclination angle of modules to maximize energy yield). In the first web application, a user may browse radiation maps and query irradiation incident on a PV module for different inclination angles. The second application simulates daily profiles of irradiance for a chosen month and module inclination and orientation. The third web application estimates electricity generation for a chosen PV configuration. It also calculates optimal inclination and orientation of a PV module for a given location. The database and the applications are accessible at http://re.jrc.cec.ev.int/pvgis/pv/imaps/imaps.htm. 相似文献
94.
Geostar地图符号的实现方法 总被引:4,自引:0,他引:4
对面向对象的 G I S软件— Geostar 中地图符号的实现方法进行了研究。分析了 Auto C A D, Arc/ I N F O 符号组织情况及其特点;用面向对象的方法对 G I S地图符号进行了抽象分类和组织;在分析符号的绘制、表示和存贮特点的基础上,提出了基于{ 代码( 图素代码或函数代码) + 参数} 符号库的建立方法;提出了7 位数字字符的方法建立《地形图图式》符号代码的方案,该方案便于建立分类与分类索引机制;对面向对象 G I S 中地图符号的组织提出了合理性的方案:通过“对照表”将空间对象与符号库联系起来,可以减少空间对象数字化和空间对象符号化时的麻烦;采用拷贝临时数据库和建立元文件索引的方法,为 G I S 获得较好的地图输出效果提供了良好的手段。 相似文献
95.
A scientific debate is in progress about the intersection of climate change with the new field of fossil fuels depletion geology. Here, new projections of atmospheric CO2 concentration and global-mean temperature change are presented, should fossil fuels be exploited at a rate limited by geological availability only. The present work starts from the projections of fossil energy use, as obtained from ten independent sources. From such projections an upper bound, a lower bound and an ensemble mean profile for fossil CO2 emissions until 2200 are derived. Using the coupled gas–cycle/climate model MAGICC, the corresponding climatic projections out to 2200 are obtained. We find that CO2 concentration might increase up to about 480 ppm (445–540 ppm), while the global-mean temperature increase w.r.t. 2000 might reach 1.2 °C (0.9–1.6 °C). However, future improvements of fossil fuels recovery and discoveries of new resources might lead to higher emissions; hence our climatic projections are likely to be underestimated. In the absence of actions of emissions reduction, a level of dangerous anthropogenic interference with the climate system might be already experienced toward the middle of the 21st century, despite the constraints imposed by the exhaustion of fossil fuels. 相似文献
96.
97.
《Journal of Great Lakes research》2019,45(6):1142-1149
The St. Clair-Detroit River System watershed is a large, binational watershed draining into the connecting channel between lakes Huron and Erie. In addition to extensive agricultural lands, it contains large urban areas that discharge phosphorus from point source facilities, runoff of impervious surfaces, and overflows of combined sewers. To help guide actions to reduce phosphorus input to Lake Erie, we analyzed the spatial and temporal dynamics of loads from the three largest urban areas in the watershed (southeast Michigan; Windsor, Ontario; and London, Ontario), and used a previously calibrated storm water management model (SWMM) to explore options for reducing loads around metro Detroit. Point sources in these three urban areas contribute, on average, 81% of the total urban load and 19% of the Detroit River’s total phosphorus (TP) load to Lake Erie, while combined sewer overflows and runoff both contribute about 10% each to the urban load and about 2.5% each to the Detroit River’s load to Lake Erie. Most of the urban load (56%) comes from a single point source, the wastewater treatment facility in Detroit; however, TP loads from that facility have decreased by about 51% since 2008 due to improvements in wastewater treatment. Model simulations suggest that increasing pervious land area or implementing green infrastructure could help reduce combined sewer overflows in certain upper portions of the metro Detroit sewer system, but reductions were much less expressed for wet-weather discharge from the system. 相似文献
98.
北京城市副中心规划防洪标准为100a一遇,其流域上游规划2座中型水库、50余处蓄滞洪区尚未建成,副中心周边防洪工程距离规划标准差距较大,导致副中心防洪安全难以保障。针对副中心来自上游的外来洪水压力大、区内防洪工程不达标等问题,采用一维、二维数学模型,分别对区域洪水风险、穿越副中心的北运河漫溢造成的淹没风险,以及副中心周边三条干流河道堤防不达标造成的防洪风险进行模拟计算和具体分析。结果表明:流域上游洪水不经有效拦蓄下泄后,将导致北运河干流100a一遇洪峰流量增加33%;同时,副中心周边三条河道均存在堤防安全风险。其中北运河发生100a一遇洪水时,即使区内宋庄蓄滞洪区建成启用,仍将有2 590万m~3洪水从3 km无堤段漫溢,并淹没副中心核心区0.2~2 m深。风险研究结果还表明,一旦近期通州境内宋庄蓄滞洪区、温潮减河分洪道等规划工程建成后,将有效降低城市副中心的部分防洪风险。研究成果对保障副中心防洪安全的规划工程实施安排及防汛抢险安排具有重要指导意义。 相似文献
99.
100.
通过对当前城市环境现状的描述,提出城市环境设计的必要,然后对城市环境设计的范围、特点、趋向、层面等进行了分析. 相似文献