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1.
我国省域农业隐含碳排放及其驱动因素时空动态分析 总被引:1,自引:0,他引:1
[目的]我国区域农业发展模式由于气候、环境的不同存在较大的差异,而目前针对农业隐含碳的时空动态研究较为缺乏,导致对于区域减排目标的设定缺乏全面的考虑,无法实现农业碳减排的效率性和公平性。因此,有必要分析农业隐含碳排放在不同省域的特征并分析其驱动因素,为制定体现地区间公平性且有效率的碳减排政策提供依据。[方法]文章利用2002年、2007年和2012年3年的投入产出表估算我国各省(市、区)农业隐含碳排放量,根据Kaya恒等关系将其分解为经济规模、经济结构、一般农业技术进步和低碳农业技术进步4类影响因素,并利用LMDI分解分析法对这4类影响因素的驱动力进行了分析。[结果]2002—2012年我国大部分地区农业隐含碳排放量呈上升趋势,空间上呈现从西到东、从南到北逐渐增加的分布规律,经济规模效应在各省份均呈正向驱动,且在经济发展较为迅速、经济增长后劲较强的地区驱动效应逐渐增强;经济结构效应在大部分省份呈负向驱动,且在重型工业的聚集区域负向效应逐渐增强;一般农业技术因素正向驱动区域逐渐扩散,且在农业大省正向驱动效应逐渐增强;低碳农业技术进步因素在东部发达地区负向的驱动效应较强,在西部驱动效应较弱。[结论]在未来的农业减排政策制定过程中,需要充分考虑不同地区的经济发展、产业结构、农业生产等特点。 相似文献
2.
为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70%且换挡品质相当.可见Tip in tip out工况对二者要求最为严格. 相似文献
3.
《Journal of Retailing》2022,98(2):277-293
This research examines how consumers’ intentions to purchase food change depending on the visualisation mode (3D vs. AR) and product format (served vs. packaged). In three studies, we demonstrate that mental simulation of eating experiences (process and outcome) mediate these effects. Study 1 shows that AR visualisation of a served food improves simulation of the eating process over 3D visualisation, with a positive effect on purchase intention. Study 2 reveals that 3D visualisation improves purchase intention for packaged products (high instrumental properties) over served products (low instrumental properties) while the opposite is true for AR visualisation. In addition, interactivity and immersion mediate the effects of 3D (vs. AR) on mental simulation of the eating process for packaged products. Study 3 extends these results by showing that 3D increases purchase intention by eliciting mental simulation of the eating outcome, when the food is visible due to transparent (vs. opaque) packaging (displaying both sensory and instrumental properties), but that no such differences emerge for AR. This research highlights the importance of using different visualisation modes to promote food depending on the product format. The findings have important implications for both offline and online retailers. 相似文献
4.
In the context of personal income tax (PIT) reform in China in 2018, this paper examines some of the major issues of concern regarding the reform and income distribution. Using the China Personal Income Tax Micro‐simulation model, the paper compares the differences between the 2011 and 2018 PIT systems, and finds that residents relying on different income sources may face a large degree of real tax rate change. Once the tax system is altered to PIT 2018, the coverage of PIT for wage earners will decrease from 46.9 to 23.4 percent, the income redistributive effect will drop from 1.95 to 1.22 percent and the PIT's role in fiscal revenue will also be negatively affected. Nevertheless, if individual income continues to grow, the share of PIT in fiscal revenue is expected to return to the 2018 level in 2022, but its income redistribution function is difficult to recover in the short term. The paper finds that the effect of PIT on income distribution depends on the tax structure. Gradual transition to an “entirely comprehensive” tax system when conditions are appropriate will achieve better income redistribution results at a lower average tax rate. 相似文献
5.
This paper investigates the driving factors behind the transition to a low carbon economy. Here, we offer a two-part analysis: First, we examine the factors leading to the current level of cleantech development. To do so, we examine the impact of country-level economic variables (real GDP, market return, and turnover) and country-level institutional variables on patent intensity. Results from this analysis show that cleantech patenting activity is fostered by a supportive institutional environment that promotes innovation and low-carbon development through carbon pricing policies, country-level public R&D expenditure and human capital. Second, we extend the notion of ‘path creation’ to map out different pathways for cleantech development on a country-level within a real options framework, and offer a corresponding valuation of cleantech patents. Our estimates of total wealth creation through the development of cleantech patents by 2050 range from US$10.16 to US$15.49 trillion dollars (13%–20% of the world GDP in 2017) with investment growth from US$2.93 to US$3.71 trillion (3.7%–4.7% of the world GDP in 2017). The results from our analysis suggest that market forces will drive the transition to a cleantech economy. 相似文献
6.
Jaehyun So Nassim Motamedidehkordi Yingjie Wu Fritz Busch Keechoo Choi 《International Journal of Sustainable Transportation》2018,12(4):286-298
This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters. 相似文献
7.
Reinhard Sellmair Tom Schelo 《International Journal of Sustainable Transportation》2019,13(7):479-496
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations. 相似文献
8.
High-speed rail (HSR) and tourism are closely related economic activities because improved mobility is perceived to facilitate tourist behavioral changes. This study examines the influence of HSR on the travel patterns of individual tourists in Taiwan in relation to time, space and carbon emissions. A framework is first provided to discuss how changes in the speed of intercity transportation will affect visitors’ choice of the journey, behavior at destinations and trip quality. In addition, HSR is expected to influence five general aspects of travel decisions relating to mobility and trip emissions, including mode selection, travel distance, length of stay per trip, annual travel frequency and total travel days. In the example of Taiwan, information by onsite sampling of 400 domestic travelers found that HSR had a weak influence on travel distance and length of stay per trip, but was observed to facilitate extended time at each stop, a deeper engagement with the locality, and an approximate 10% reduction in transport carbon emissions through intermodal substitution. These phenomena are in line with the slow travel concept of sustainable tourism consumption. 相似文献
9.
Marcin Maleszka 《Enterprise Information Systems》2019,13(7-8):1120-1142
ABSTRACTWe present a group dynamics model that shows knowledge integration as a process occurring over time. As each individual in the group contact others, his own knowledge changes, and over time the collective knowledge is obtained. This allows modeling knowledge diffusion in a social network and while the models presented in this paper are not competitive in that area, they approach the problem from previously unconsidered direction. We test the behavior of the model in a multi-agent simulation and we test a simple advertisement campaign in a social network. We provide discussion of elements needed for making model more competitive. 相似文献
10.
Sohanur Rahman Tehmina Khan Pavithra Siriwardhane 《Business Strategy and the Environment》2019,28(6):1072-1082
Although corporate environmental disclosures have been researched extensively, empirical evidence regarding the indirect impact of carbon pricing on firms' voluntary disclosures is scarce. The objective of this study is to identify the indirect impact of carbon pricing initiatives on the voluntary environmental disclosures (VEDs) of electricity generating companies, analyzed through the lens of institutional theory. This study adds to the growing literature on the determinants of VED, investigating the impact of adoption of the Global Reporting Initiative and ISO 14001 on VED. Secondary data were collected from 2015 annual reports and/or standalone sustainability reports of electricity generating companies from 53 countries around the world. Content analysis approach was adopted for measuring the extent of the quality of VED. Findings of multiple regression analysis suggest that there is an indirect institutional impact of carbon pricing on the quality of VED. This study also finds that, as the form of nongovernment guidance, the Global Reporting Initiative adoption and ISO 14001 certification also have an institutional influence on the VED. VED is also affected by company size although this study reveals no significant relationship of leverage with VED. 相似文献