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In response to global warming, it is urgent to control and reduce greenhouse gas (GHG) emissions, especially from the supply chain perspective. The most often discussed topic in this domain indicates that emission trading scheme (ETS) could be employed as one of policy instruments for supply chain emissions management. Via mathematical models, scholars have shown that the employment of emission trading is affecting supply chain performances (both environmental and economic) in different levels. However, previous literature focus on the cost-effectiveness analysis only from the mathematical aspect. To provide policy-makers and companies with the theoretical bases on this hot topic, it is significant to discuss how ETS, one of market-based instruments, could be imposed in the context of supply chain from the mechanical point of view. By incorporating ideas from relevant literature, this paper generates two concepts/modes in imposing ETS on supply chain: jointly imposed supply chain emission trading (e.g., jointly imposed SC-ETS) and separately imposed supply chain emission trading (e.g., separately imposed SC-ETS). It illustrates the working principles of both concepts/modes and conducts a sandbox example to analyze the cost-effectiveness of them. Furthermore, this paper discusses the challenges and opportunities of implementing two modes from practical aspects. Results of quantitative analysis and discussion show that for the sake of both policy-makers and supply chain companies, the separately imposed SC-ETS allowing selling permits would be so far the better mode to manage supply chain GHG emissions compared to the jointly imposed SC-ETS. [ABSTRACT FROM AUTHOR]

Combustion of fossil fuels in the transport sector represents the second largest source of greenhouse gas emissions. For this reason, governments are fostering diversification of energy sources by creating a set of governmental environmental policies and initiatives. In this context, biofuels are expected to represent a substantial part of source diversification, but it is necessary to assess the sustainability of their market to explore its effect on economical, technological, social, political and environmental dimensions. This research presents a dynamic simulation modelling of the Colombian biodiesel market and analyzes the policy support instruments for creating and managing it. A system dynamics based model is proposed to enable decision-makers to understand the influences between the different variables that describe the system and the impact of the biodiesel government policy in Colombia. The primary focus of this paper is to establish the characteristics of each sustainability dimension for the case of study and apply the system dynamics methodology with different types of validation. Finally, the Colombian market status and a sensitivity analysis are developed. The results show that in order to support the development of this sector, it is necessary to diversify the raw materials for the production of biodiesel in the medium term, which means raw materials without competence for the primary rainforest or competition with food productive lands. [ABSTRACT FROM AUTHOR]

Construction and demolition waste (C&DW) is currently a worldwide issue, and the situation is the worst in China due to a rapid increase in the construction industry and the short life span of China's buildings. To create an opportunity out of this problem, comprehensive prevention measures and effective management strategies are urgently needed. One major gap in the literature of waste management is a lack of estimations on future C&DW generation. Therefore, this paper presents a forecasting procedure for C&DW in China that can forecast the quantity of each component in such waste. The proposed approach is based on a GM-SVR model that improves the forecasting effectiveness of the gray model (GM), which is achieved by adjusting the residual series by a support vector regression (SVR) method and a transition matrix that aims to estimate the discharge of each component in the C&DW. Through the proposed method, future C&DW volume are listed and analyzed containing their potential components and distribution in different provinces in China. Besides, model testing process provides mathematical evidence to validate the proposed model is an effective way to give future information of C&DW for policy makers. [ABSTRACT FROM AUTHOR]