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Abstract The negative appraisals of the impact of airline industry on climate change have forced the industry to become greener. Over the past several decades, CO 2 emissions in the airline industry have increased considerably, thereby adversely affecting the environment. Therefore, airlines are seeking different approaches to reduce the environmental degradation. In this paper, we study cruise speed control to achieve this goal by reducing CO 2 emissions while studying passenger service level. We use some indicators to measure the passenger service level in the airline industry. These indicators create a conflict between CO 2 emissions and passenger service level. We develop a bi-objective mixed-integer non-linear programming model to integrate flight scheduling, aircraft-path assignment, and gate assignment with the aim of reducing CO 2 emissions while increasing passenger service level. Based on a real problem, the model can lead to 11% and 31% improvement in CO 2 emissions and passenger service level, respectively. The model is NP-hard. Therefore, we develop a new constructive heuristic method, and we also use the multi-objective simulated annealing algorithm and extend this algorithm to enhance its performance. We also use the design of experiment and Taguchi method to optimize the algorithms parameters. Finally, we evaluate the proposed methods based on information retrieved from major U.S. airlines. [ABSTRACT FROM AUTHOR]

The so-called Paris Agreement, signed by 195 countries, has led to the setting of some ambitious target reductions in greenhouse gas emissions by most developed countries. The over-arching goal of those reduction targets is to limit global warming to less than 2 o C compared to pre-industrial levels. Yet, despite these commitments from the highest governance levels, there is still no deterministic model on how these national target reductions will be cascaded down to the commercial sector, which accounts for the lion's share of these emissions. In this paper, we present a novel framework which enables the setting, measurement and tracking of the emissions performance of every commercial entity based on a single metric. We further present empirical evidence from the automotive industry to illustrate how the model helps to readily identify the low versus high performers. The model also reveals one car company that stands out as the industry benchmark by already exceeding the performance required by the 2025 emissions target set by the US. The model proves successful in achieving the objectives of being: science-based, goal-driven, equitable, comparable and actionable, and as such can be readily used to accurately compare competitors from the same industry and provide the basis of a more equitable, performance-based carbon tax market, as well as the ability to assess accurately how well a specific country is meeting its reduction quota and how the various industry sectors are impacting that goal. [ABSTRACT FROM AUTHOR]

Various environmental regulations put ever stringent requirements on the automotive industry as a part of solution to the problem of global warming and climate change. In Europe, the upcoming Euro 6 standard that will come into force on September 1, 2014 demands reduction in NO x emissions from cars and vehicles intended for transport by more than 50% compared to the current standard. The urea-water-solution (UWS) based selective catalytic reduction (SCR) is currently the most promising method for fulfilling these requirements. In principle, the UWS spray is injected into a hot exhaust gas stream preceding the SCR catalyst and ammonia is generated through series of chemical reactions. Then, the generated ammonia acts in various deNO x reactions as a reductant. This paper investigates application of numerical modeling in the area of environmentally friendly technology of mobile SCR as a green engineering measure to reduce pollution in the road transport sector. Within this work the mathematical model of surface tension has been developed and compared to analytical expression for isothermal droplet spreading. Furthermore, this model was incorporated into the wall film module of the commercial computational fluid dynamics code FIRE for description of urea-water-solution injection into hot exhaust gases of diesel engine and compared to experimental data. Results of the conducted numerical study support the feasibility of commercial application of the presented model. [ABSTRACT FROM AUTHOR]