A comparison of trends and magnitudes of household carbon emissions between China, Canada and UK

Household carbon emissions (HCEs) contribute a large proportion of global carbon emissions. For several reasons there are large differences in HCEs between countries. Using governments’ annual data, this study aims to compare the trends and magnitudes of HCEs between China, Canada and the UK and pinpoint where these countries are heading and what lessons they can learn from others. In the years when HCEs were first reported (1995 in China, 1990 in Canada and 1997 in UK), per person HCEs in China, Canada and the UK were 0.54 tCO2, 13.54 tCO2 and 9.63 tCO2, respectively. These values had changed to 1.77 tCO2, 13.14 tCO2, 8.20 tCO2 by the end of reporting (2011 in China and UK and 2007 in Canada), representing an increase of 7.7%/yr in China and a decrease of 0.18%/yr in Canada and 1.14%/yr in the UK. Although the rate of ncrease in China was high, in absolute terms China’s per person CE remained many times lower than that of Canada and the UK. The reasons why China may not follow Canada and UK’s emissions pathways are discussed. In comparison with several other studies, China’s average HCEs were found to be much lower than that of developed countries. Among the developed world, Sweden and Norway had much lower HCEs, probably due to the production of electricity by hydro and nuclear power generation and the use of centralised heating systems in Sweden, and production of electricity by hydropower in Norway. Where possible, countries all around the world can learn lessons from these two countries

Characteristics and trends of household carbon emissions research from 1993 to 2019 A bibliometric analysis and its implications

The study of household carbon emissions (HCEs) has become one of the most important topics in sustainability research due to the growing awareness of its significances in responding to global warming. This paper aims to identify the trends and characteristics of HCEs research for the period 1993-2019 through the bibliometric analysis approach. The impacts of most productive journals, countries, institutions and authors are evaluated by citation analysis, while the co-authorship network between various countries, institutions as well as the co-occurrence among different keywords are presented. The results of this paper provide a detailed picture on HCEs-related articles from 1993 to 2019. Both the number of publications on HCEs and the cooperation among countries and institutions have increased during the period. Keyword analysis suggests that the revelation of current status of HCEs and corresponding influencing factors are the main lines of HCEs research, and the prediction of HCEs should become the focus of future research. The valuable results obtained from this study can help the academic professionals keep informed of the latest developments in the HCEs-related field.</p

降级路网组合出行交通流分配模型与算法 = Traffic assignment model and algorithm with combined modes in a degradable transportation network

研究降级路网条件下的组合出行交通平衡问题。首先，基于出行者对降级路网的不同风险态度，将出行者分为三类：守时型，冒险型和平均型。其次，考虑小汽车出行和小汽车换乘地铁出行两种出行模式，分析降级路网条件下不同用户类的组合出行行为，建立相应的多用户变分不等式交通分配模型，讨论模型解的性质。最后，设计模型的求解算法，并通过算例说明模型和算法的有效性。算例结果表明：不同出行时间预算的出行者在降级路网中的路径选择行为存在较大差异，路网降级程度对出行者出行选择行为影响显著；随着道路通行能力的降低，出行者更倾向于选择组合出行模式。To study the effect of the degradable road network on travel decision and traffic assignment, firstly all travelers were categorized into three classes: risk-averse travelers, risk-prone travelers and risk-neutral travelers. Secondly, two travel modes including car trip and car-subway trip were considered in a multi-modal networks. A stochastic traffic equilibrium model was proposed by using the variational inequality theory, and the properties of the solution were discussed. Finally, an example was used to testify the validity of the model and the algorithm. The results show that the travel behavior varies greatly with different travel time budget; with the decrease of traffic capacity, travelers prefer to choose the combined modes.Accepted versio