The present study examines the long-run and short-run impacts of fossil fuels consumption, foreign direct investment and economic growth on carbon emissions in fifteen developing Asian countries. Our ...empirical evidence analyses panel data for the period from 1990 to 2013, and it applies an Autoregressive Distributive Lag (ARDL) model. Our results show that in these developing economies, the efforts to foster economic growth are contributing to the generation of CO2 emissions, and that fossil fuels consumption is contributing to carbon emissions and to the deterioration of the environment at the regional level. Moreover, the empirical results spotlight that foreign direct investment is a source of environmental degradation that increases carbon emissions at the domestic level, confirming the Pollution Haven hypothesis. Furthermore, our data confirms the existence of an Environmental Kuznets Curve (EKC) in these developing Asian countries. Finally, our study suggests that reducing the consumption of fossil fuels and fostering an environmentally friendly economic growth strategy in these developing countries will prove helpful for the well-being of this part of the developing world.
•The efforts to foster economic growth in Asia are increasing environmental challenges.•The study shows that the use of fossil fuels energy is increasing carbon emissions.•The study depicts, FDI in developing countries is significant source of CO2 emissions.•Results show a bell-shaped relationship between economic growth and CO2 emissions.•Results confirm the pollution haven hypothesis and reject halo effect hypothesis.
With the development of automated driving and communication technologies, the connected automated vehicles (CAVs) gradually enter market and become more popular. At the same time, the mixed traffic ...composed of conventional vehicles and CAVs will gradually become a very common form of traffic. In fact, the driving process of CAV is a typical cyber physical process which couples tightly the cyber factor of traffic information with the physical components of the vehicles. In this paper, we present a mixed traffic model from the perspective of cyber physical fusion, the model focuses on the fact that the CAVs can obtain the information from multiple vehicles ahead and the drivers have a reaction delay in driving process. The stability condition of the proposed model is derived via linear stability analysis. Furthermore, we investigate the fuel consumption and CO2 emission using the model we propose under different penetration rates of CAVs. The results show that the stability of mixed traffic is related to driver’s reaction delay, the penetration rate of CAVs, and the information from multiple vehicles ahead that CAVs can obtain. Numerical simulations are conducted to verify the analytical results. The simulation results demonstrate that the model proposed in this paper can better reflect the real advantages of CAV in mixed traffic, and further show that the model in this paper is more realistic. More specifically, the information obtained from multiple vehicles ahead including conventional vehicle and CAV can improve the stability of mixed traffic and traffic efficiency to a greater extent, and the driver’s reaction delay will destabilize mixed traffic. Besides, when the penetration rate of CAVs is high, the fuel consumption and CO2 emission in mixed traffic can be greatly reduced.
•A general model framework of mixed traffic is proposed.•Multiple vehicles ahead and driver’s reaction delay are considered in the model.•The stability condition of the model is derived via linear stability analysis.•The fuel consumption and CO2 emission using the model we propose are investigated.
•Propose a multi-stage optimal control problem to minimize vehicle fuel consumption.•Consider the impacts from queue on the optimal vehicle speed trajectory.•Develop a constrained optimization model ...to solve the problem efficiently.
Vehicle speed trajectory significantly impacts fuel consumption and greenhouse gas emissions, especially for trips on signalized arterials. Although a large amount of research has been conducted aiming at providing optimal speed advisory to drivers, impacts from queues at intersections are not considered. Ignoring the constraints induced by queues could result in suboptimal or infeasible solutions. In this study, a multi-stage optimal control formulation is proposed to obtain the optimal vehicle trajectory on signalized arterials, where both vehicle queue and traffic light status are considered. To facilitate the real-time update of the optimal speed trajectory, a constrained optimization model is proposed as an approximation approach, which can be solved much quicker. Numerical examples demonstrate the effectiveness of the proposed optimal control model and the solution efficiency of the proposed approach.
Although there have been numerous studies on economic policy uncertainty (EPU), its impact on firms' emissions has not often been examined. Using an unbalanced panel data of firms and a newly ...constructed provincial EPU index in China, this paper estimates the impact of EPU on manufacturing firms' carbon emission intensity. We further test the likely channels through which EPU can affect firm emission intensity, including the innovation channel, share of fossil fuels in the total energy consumption channel, and energy intensity channel. The findings show that China's provincial EPU imposes a significantly positive impact on firms' carbon emission intensity. The channel analysis shows that EPU influences carbon emission intensity through the share of fossil fuels in the total energy consumption and energy intensity in the short run, but not firm innovation. The results indicate that manufacturing firms prefer to use cheap and dirty fossil fuels to respond to the rising EPU. This paper suggests that policymakers should pay careful attention to the increasing effect of EPU on carbon emission intensity which could undermine China's emission reduction efforts and other sustainable development goals.
•A new provincial economic policy uncertainty (EPU) index is constructed.•First study to investigate the impact of EPU on carbon emission intensity at the firm level in China.•The EPU index of eastern coastal areas is higher than that of western inland areas.•The fuel mix and energy intensity channels are significant, but the innovation channel is not.•Chinese firms prefer to use cheap and dirty fossil fuels to react to the rising EPU.
The green-car subsidy program since 2009 has been successfully used to boost the nation's new-energy vehicle industry and cut vehicle emissions in China; however, it may cause financial burden on the ...governments at the same time. Therefore, alternatives including a New-Energy Vehicle Credit Program and Corporate Average Fuel Consumption Regulation (dual-credit policy) have been proposed to reduce the government's expenditure caused by subsidization. To examine the effectiveness of the new regulation, new energy vehicles' development under different scenarios have been quantitatively simulated by using a developed game theory-based analysis model. The obtained results show that: (i) the dual-credit policy can effectively promote the development of new energy vehicles, with this policy (in scenario NSC and SC) the proportion of NEV in the whole auto market will be up to 3.9%; (ii) compared with green-car subsidy, the dual-credit policy can significantly increase the amount of new energy vehicles to two times as much as that of current subsidy level; and (iii) when the dual-credit policy is implemented, green-car subsidy will not further promote the development of new energy vehicles.
•The substitution effects of the dual-credit policy for subsidy was analyzed.•A game theory based comprehensive analysis model was proposed.•The dual-credit policy can increase the new energy vehicles' production significantly.•Subsidies are no longer indispensable under the dual-credit policy.
The stages of the development of fuel consumption regulation for vehicles in the USSR and in the Russian Federation are shown, and the main concepts of the research into fuel consumption regulation ...for buses are described. The paper considers mathematical models to predict fuel consumption for vehicles with regard to high-speed movement modes, and determines fuel consumption for city buses.
The bi-objective Pollution-Routing Problem Demir, Emrah; Bektaş, Tolga; Laporte, Gilbert
European journal of operational research,
02/2014, Letnik:
232, Številka:
3
Journal Article
Recenzirano
•A bi-objective variant of the Pollution-Routing Problem (PRP) is introduced.•Several multi-objective optimization techniques are developed and tested for the problem.•The proposed methods find ...trade-offs between fuel consumption and driver times.•Results of experimentation conducted on realistic instances are presented.
The bi-objective Pollution-Routing Problem is an extension of the Pollution-Routing Problem (PRP) which consists of routing a number of vehicles to serve a set of customers, and determining their speed on each route segment. The two objective functions pertaining to minimization of fuel consumption and driving time are conflicting and are thus considered separately. This paper presents an adaptive large neighborhood search algorithm (ALNS), combined with a speed optimization procedure, to solve the bi-objective PRP. Using the ALNS as the search engine, four a posteriori methods, namely the weighting method, the weighting method with normalization, the epsilon-constraint method and a new hybrid method (HM), are tested using a scalarization of the two objective functions. The HM combines adaptive weighting with the epsilon-constraint method. To evaluate the effectiveness of the algorithm, new sets of instances based on real geographic data are generated, and a library of bi-criteria PRP instances is compiled. Results of extensive computational experiments with the four methods are presented and compared with one another by means of the hypervolume and epsilon indicators. The results show that HM is highly effective in finding good-quality non-dominated solutions on PRP instances with 100 nodes.
The present work is intended to improve the performance of a direct injection compression-ignition engine fuelled with nanoparticle dispersed Flaxseed oil biodiesel blend (B20). The Chromium oxide ...(Cr2O3) nanoparticle additive with dispersant (QPAN 80) was mixed to B20 in concentrations of 50, 75, and 100 ppm. Tests were performed to assess the engine operating characteristics under varying load conditions such as 25, 50, 75, and 100% by maintaining a uniform speed of 1500 rpm. The combustion characteristics namely cylinder pressure (CP) and net heat release rate (NHRR) have greatly improved with the nanoparticle dispersed fuel than diesel-biodiesel blends. Besides, the brake thermal efficiency (BTE) has enhanced together with lower brake specific fuel consumption (BSFC). Finally, a significant decrease in emissions like carbon monoxide (CO), unburnt hydrocarbons (UHC), smoke, and nitrogen oxides (NOx) were observed. At maximum load, the CP and NHRR have improved by 18.66% and 11.61% respectively for B20Cr2O375DS1 (B20 with 75 ppm Cr2O3 and 1:1 dispersant) while the BTE has enhanced by 3.62% and the BSFC reduced by 3.53% compared to normal diesel. The reduction in CO, UHC, NOx, and smoke were found to be 14.05%, 12.93%, 6.66%, and 22.4% respectively for B20Cr2O375DS1 than conventional diesel.
•Good stability was caused for B20 with surface modified Cr2O3 nanoparticles.•BTE was improved by 3.62% while the BSFC was lowered by 3.53% for B20Cr2O375DS1.•Enhancement of CP and NHRR for B20Cr2O375DS1were seen by18.66% and 11.61%.•Lower emissions were noticed together with NOx for B20Cr2O375DS1.
Fuel consumption accounts for a large and increasing part of transportation costs. In this paper, the Fuel Consumption Rate (FCR), a factor considered as a load dependant function, is added to the ...classical capacitated vehicle routing problem (CVRP) to extend traditional studies on CVRP with the objective of minimizing fuel consumption. We present a mathematical optimization model to formally characterize the FCR considered CVRP (FCVRP) as well as a string based version for calculation. A simulated annealing algorithm with a hybrid exchange rule is developed to solve FCVRP and shows good performance on both the traditional CVRP and the FCVRP in substantial computation experiments. The results of the experiments show that the FCVRP model can reduce fuel consumption by 5% on average compared to the CVRP model. Factors causing the variation in fuel consumption are also identified and discussed in this study.
•Original model to investigate the performance of storage tanks with solar coil and PCM.•Simulation of storage tanks that serve a public swimming pool.•Simulation of storage tanks' operation in ...different working conditions.
Thermal energy storage tanks have a fundamental role in the preparation and simultaneous distribution of domestic hot water. These tanks are supplied with thermal energy via classical means, based on electrical energy and fuel combustion, and via renewable energy sources.
This study investigates the possibility of reducing the storage tank’s accumulation volume by employing phase change materials to store high densities of thermal energy at constant temperatures. A mathematical model was developed to simulate the operation of storage tanks equipped with immersed solar coil, also taking into account the addition of phase change materials encapsulated in cylindrical containers. The mathematical model was validated based on literature data. The simulation program also determines the temperature of the primary heat transfer fluids, prepared by a solar collector system and a flat plate heat exchanger coupled with a gaseous fuel boiler. The program was used to study the performance of storage tanks that serve a public swimming pool, a type of building that is characterized by a high demand of domestic hot water. To the best knowledge of the authors, this scenario was not reported in the literature.
The study revealed that the nominal volume of the storage tanks can be reduced by 25% in comparison to the classic alternative, by using phase change materials as thermal storage. Also, the tanks equipped with phase change material achieved a reduction of fuel consumption and CO2 emissions by (5.00-11.97) % in comparison to the classic solution.
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