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31.
In developing countries, providing all citizens an access to modern forms of energy is among the central energy policy objectives, as the linkages between modern energy services and human development are widely recognized. This paper presents in a scenario analysis of rural energy consumption, how energy services in different sectors of a village economy contribute to the achievement of the UNDP Millennium Development Goals. In a rural village in Lao People’s Democratic Republic, household energy demand and energy uses were surveyed immediately prior to the electrification of the village. Based on the situation preceding electrification of the village, the development of village electrification was studied by simulating the village energy system, accounting for all village energy uses but transportation. To study the potential development of electricity demand in the village, three scenarios were constructed using the LEAP model: “residential demand”, “income generation” and “public services”. Energy demand in each scenario was analyzed with reference to the Millennium Development Goals.  相似文献   
32.
杜焕强  袁思达  陈军 《计算机教育》2010,(16):141-143,146
操作系统安全实训综合运用操作系统安全与局域网组建的基础知识,是一个实用性很强的综合实践环节。针对目前高职院校实习实训基地条件受限、实训过程跟踪困难及评价方式单一,提出工作场景模拟的实训课程思想,以具体教学过程为主线指出工作场景模拟、学生角色扮演和教师的作用。  相似文献   
33.
India’s growing population and economy generate an increasing demand for energy. Facing the decline of global fossil fuel resources, the Indian government and energy industry are considering the long-term expansion of biofuel production in order to increase energy security. This development leads to a strong competition of energy crops versus food crops for land and may result in an increasing pressure on natural resources. In a pilot scenario study, the LandSHIFT model is applied to assess the impact of biofuel production on land-use change in India up to the year 2030. The model aims at the spatially explicit simulation of land-use change and its relation to other global change processes on the national up to the global scale. It explicitly addresses competition between land-use activities such as human settlement, biofuel production and food production as well as the resulting effects on the spatial extent of natural land. Baseline of the study is a simulation with drivers from the “Order from Strength” scenario of the Millennium Ecosystem Assessment. To illustrate the consequences of expanded biofuel production for the extent of natural land, we calculate three scenarios of bioethanol production to substitute 5%, 10% and 20% of the expected petrol demand in 2030. In the simulations shown, a comprehensive linkage is made between driving forces (such as population change) and policies (such as biofuel usage) that will affect land-use change over the coming decades.  相似文献   
34.
The current situation regarding the maintenance of concrete structures in Japan is reviewed. Firstly, the Standard Specification for Concrete Structures ‘Maintenance’ is introduced. Secondly, the Manual for Maintenance of Pre-stressed Concrete Bridges is explained for pre-stressed concrete bridges. In addition, Recommendations on Design and Construction of Electrochemical Corrosion Protection is briefly presented as the most recent set of recommendations on maintenance.  相似文献   
35.
Refueling costs account for much of the fuel cost for light-duty hydrogen fuel-cell electric vehicles. We estimate cost savings for hydrogen dispensing if metal hydride (MH) storage tanks are used on board instead of 700-bar tanks. We consider a low-temperature, low-enthalpy scenario and a high-temperature, high-enthalpy scenario to bracket the design space. The refueling costs are insensitive to most uncertainties. Uncertainties associated with the cooling duty, coolant pump pressure, heat exchanger (HX) fan, and HX operating time have little effect on cost. The largest sensitivities are to tank pressure and station labor. The cost of a full-service attendant, if the refueling interconnect were to prevent self-service, is the single largest cost uncertainty. MH scenarios achieve $0.71–$0.75/kg-H2 savings by reducing compressor costs without incurring the cryogenics costs associated with cold-storage alternatives. Practical refueling station considerations are likely to affect the choice of the MH and tank design.  相似文献   
36.
Pen-based user interface (PUI) has drawn significant interest, owing to its intuitiveness and convenience. While much of the research focuses on the technology, the usability of a PUI has been relatively low since human factors have not been considered sufficiently. Scenario-centric designs are ideal ways to improve usability. However, such designs possess some problems in practical use. To cope with these design issues, the concept of “interface scenarios” is proposed in to facilitate the interface design, and to help users understand the interaction process in such designs. The proposed scenario-focused development method for PUI is coupled with a practical application to show its effectiveness and usability.  相似文献   
37.
Observation is the beginning of reading site and inspiring design. When the site lacks obvious features, designers not only need to observe in detail but also step out of the site’s physical boundaries and expand the scope of observation. This process involves reflection on the intrinsic factors of the site, seeking landscape reference in the broader context according to the subject’s core connotations, through which design concepts can emerge from the simulation, selection, and expression of scenarios. The new Duke Garden, located in the city of Kunshan in Jiangsu Province, is situated in a typical Chinese suburban area, which bears little distinction in geographical features. The ordinary site condition forced designers to search for deeper characteristics of the place through alternative methods which allow designers to examine the site from three perspectives: 1) through the study and comparison of precedents which share a spiritual lineage; 2) through the physiographical investigation on regional ecosystem to which the site belongs; and 3) through a revisit of the preceding phases of the project and a probe into the temporal connection between adjacent sites. Observations from these three perspectives have enabled the design of Duke Garden to explore contemporary spiritual connotations of the landscape typology of “garden” and intepret it through this project.  相似文献   
38.
Landscape planning adjusts spatial structures and functions by altering the types of land use / land cover and the patterns of landscapes, and thus further impacts ecosystem services. This paper examines the impacts of landscape planning on ecosystem services and draws the conclusion that the control over the types of land use / land cover, the altering of landscape patterns, and the adjustment of landscape functional characteristics could change the type, quality, and performance of ecosystem services, respectively. Through an overall review on the application of ecosystem service evaluation, spatial mapping, and scenario simulation, this paper further concludes their roles in landscape planning: ecosystem service evaluation provides means to ensure scientific landscape planning; spatial mapping serves as a basis to the decision making; and scenario simulation visualizes all kinds of possibilities for an optimal choice. At the same time, such applications in landscape planning practices, ranging from green space planning, ecological conservation redline planning, land use planning to biodiversity protection planning, are exemplified. Finally, this paper summarizes existing research findings and limitations and proposes that future research is expected to study the relationship between landscape planning and ecosystem services, to build a dynamic composite planning framework that can improve ecosystem services, and to propel the research on the tradeoff-and-synergy among ecosystem services in landscape planning.  相似文献   
39.
Models to evaluate the impact of plant diseases on crop production under current and future climatic conditions are increasingly requested by different stakeholders. This paper presents four software components – InoculumPressure, DiseaseProgress, ImpactsOnPlants, AgromanagementDisease – which implement models to simulate the dynamics of generic polycyclic fungal epidemics and interactions with crop physiological processes. The software architecture adopted allows extending the components with alternate approaches to reproduce specific pathosystems or compare predictive capabilities. As proofs of concept, (i) the components are coupled with two crop simulators to reproduce wheat brown rust and rice blast epidemics and their impacts on leaf area and yield formation; (ii) spatially distributed sensitivity analyses are performed for rice in China and wheat in Europe to investigate model behaviour; (iii) a preliminary evaluation against observations of rice blast severity is performed in Northern Italy. The components are explicitly targeted to the modelling of crop–pathogen interactions to perform scenario analysis.  相似文献   
40.
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