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161.
Xinyou Lin Guangji Zhang Shenshen Wei Yanli Yin 《International Journal of Green Energy》2020,17(8):488-500
ABSTRACT The drive range of electric vehicle (EV) is one of the major limitations that impedes its universalism. A great deal of research has been devoted to drive range improvement of EV, an accurate and efficiency energy consumption estimation plays a crucial role in these researches. However, the majority of EV’s energy consumption estimation models are based on single motor EV, these models are not suitable for dual-motor EVs, which are composed of more complex transmission mechanisms and multiple operating modes. Thus, an energy consumption estimation model for dual-motor EV is proposed to estimate battery power. This article focuses on studying the operating modes and system efficiency in each operating mode. The limitation of working area of each mode ensures the vehicle dynamic performance, then PSO algorithm is adopted to optimize the torque (speed) distribution between two motors to improve the system efficiency in the coupled driving mode. Finally, the energy consumption estimation model is established by multiple linear regression (MLR). The result shows that the proposed model has a high precision in energy consumption estimation of dual-motor EV. 相似文献
162.
Sustainable Tourism and the Touristic Ecological Footprint 总被引:27,自引:0,他引:27
Colin Hunter 《Environment, Development and Sustainability》2002,4(1):7-20
There is growing interest in ecological footprint analysis in aiding our understanding of societal demands upon the biosphere. Increasingly, attention is being focused on potential new applications of the technique. Tourism is one of the world's largest industries and can play a major part in encouraging more consumerist lifestyles. It is now widely accepted that tourism development may have profound impacts on local environments, and that, consequently, the sustainable development of tourism at destination areas is an important issue. However, sustainable tourism studies rarely look beyond the destination area, and there has been no substantive recognition of the wider ecological footprint of tourism activities. This paper attempts to connect, conceptually, the realms of sustainable tourism and ecological footprint thinking. In so doing, various conceptualisations of the 'touristic ecological footprint' (TEF) are suggested, along with some potential applications. It is argued that primary research should focus on calculating the touristic ecological footprint associated with individual tourism products, throughout the product's life-cycle. As well as bringing another dimension to our understanding of tourism's actual ecological demand, it is also argued that the concept of the touristic ecological footprint may be used to clarify theoretical aspects of the sustainable tourism debate, helping to rejuvenate this debate in the process. 相似文献
163.
本文分析了流域水资源开发利用中存在的问题及原因,并根据可持续发展的理论,提出了流域水资源可持续开发利用的原则及相应的激励机制:①水价机制;②宏观调控机制;③水权机制;④相应的流域管理机制。 相似文献
164.
Hong?ZhengEmail author Yoshitaka?Nitta Isamu?Yokota 《Journal of Material Cycles and Waste Management》2004,6(2):153-161
In this article, the systems for the collection and intermediate processing of used beverage cans (UBCs) are compared and analyzed, focusing on the time taken and the cost of processing, the energy consumption, and the emissions of CO2, SO
x
, and NO
x
, during the process. We found that cases where the UBCs were crushed in the discharging process gave better results, and how the UBCs were collected was the most important factor. It was more desirable to treat UBCs in one place than in two places. When the transportation distance was longer, the pressed form of UBCs was more convenient. When the transportation distance was short, the original form, the crushed form, and the shredded form of UBCs were all suitable. That is, the contribution of the transportation process to the evaluation was large when the transport distance was long, and the contribution of the treatment process was large when the transport distance was short. 相似文献
165.
166.
We examined the impact of single-tree selective logging and fuel reduction burns on the abundance of hollow-nesting bird species
at a regional scale in southeastern Queensland, Australia. Data were collected on species abundance and habitat structure
of dry sclerophyll production forest at 36 sites with known logging and fire histories. Sixteen bird species were recorded
with most being resident, territorial, obligate hollow nesters that used hollows that were either small (<10 cm diameter)
or very large (>18 cm diameter). Species densities were typically low, but combinations of two forest management and three
habitat structural variables influenced the abundances of eight bird species in different and sometimes conflicting ways.
The results suggest that habitat tree management for biodiversity in production forests cannot depend upon habitat structural
characteristics alone. Management histories appear to have independent influence (on some bird species) that are distinguishable
from their impacts on habitat structure per se. Rather than managing to maximize species abundances to maintain biodiversity, we may be better off managing to avoid extinctions
of populations by identifying thresholds of acceptable fluctuations in populations of not only hollow-nesting birds but other
forest dependent wildlife relative to scientifically valid forest management and habitat structural surrogates. 相似文献
167.
"开放型"区域资源策略探析--以浙江省为例 总被引:1,自引:0,他引:1
本文从区域资源安全的内涵出发,以浙江省为研究对象,在分析了省域资源条件及供给现状的基础上,提出了构建“开放型”区域资源安全体系的总体思路。 相似文献
168.
中国可持续发展信息共享现状和展望 总被引:8,自引:0,他引:8
本文阐述了开展可持续发展信息共享的的意义和存在的障碍,介绍了信息共享的现状和中国持续发展信息网的成就,提出了深入开展信息共享的对策建议。 相似文献
169.
170.
秦皇岛市50年来气候变暖变干,年平均气温提高2.3℃,≥10℃年积温增加11.4%,无霜期延长22天,但年平均降水量却减少12.6%。这对农业和工业的影响弊大于利,对旅游业的影响则有利有弊。为此应趋利避害,加强水资源的开源节流,发展节水经济和循环经济,发展休闲度假旅游,延长旺季。 相似文献