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This letter presents a stochastic robust framework for two-stage power system optimization problems with uncertainty. The model optimizes the probabilistic expectation of different worst-case scenarios with different uncertainty sets. A case study of unit commitment shows the effectiveness of the proposed model and algorithms.

Abstract This paper presents the transient performance of a single basin solar still coupled with a flat plate collector. The average daily production of distilled water has been found to be 24% higher than for a simple single basin solar still

The climate crisis and the increasing temperature of the earth have highlighted the need to reduce carbon emissions in supply chains, which has gradually become a global consensus. The focus has often been on traditional carbon emission industries, such as energy and transportation, while the pharmaceutical industry has received little attention. This paper, therefore, aims to fill that research gap by exploring the carbon emission reduction mechanisms of the pharmaceutical supply chain, specifically the role of public participation. We constructed a quadrilateral evolutionary game model, based on evolutionary game theory, consisting of local government, pharmaceutical manufacturers, wastewater treatment plants, and the public. By finding the equilibrium point of the system of replicator dynamics, evolutionary stable strategies are obtained. Our numerical simulation shows the impacts of the principal strategy change and the key variables. This paper also identifies some management implications: 1) When local governments implement a combination policy (carbon subsidies and carbon tax policy), the key is to formulate a subsidy level satisfactory to the four parties. If the subsidy level is in the middle level, the four parties are at their most willing to participate in carbon emission reduction. 2) When local governments implement a single policy (carbon tax policy), the carbon tax rate becomes the key variable. A high level of carbon tax accelerates carbon emission reduction in the pharmaceutical supply chain. 3) No matter what policies local governments implement, the free-rider effect between pharmaceutical manufacturers and wastewater treatment plants always hinders their low-carbon decisions. 4) Public reporting is an effective measure for promoting carbon emission reduction in the pharmaceutical supply chain. When local governments implement a combination policy, it can reduce the cost of reporting and improve the willingness of the public to report. Finally, we put forward suggestions for rationalizing carbon emission reduction.

[EN]The extraordinary thermal-to-electricity conversion efficiency of thermally regenerative electrochemical cycle triggers interest in its reverse counterpart, namely thermally regenerative electrochemical refrigerator (TRER), a promising alternative to conventional cooling devices. Nevertheless, due to three fundamental obstacles, the practically feasible TRER model is still absent, which hinders the development of follow-up research. To break this bottleneck, heating by discharging and cooling by charging effects are innovatively utilized to construct TRER models where the electrochemical counterparts of traditional adiabatic compression and expansion processes, namely adiabatic pre-charging and pre-discharging processes, are proposed and introduced. Significantly, the maximum coefficient of performance (COP) and the COP at maximum cooling power are predicted to achieve up to 40% and 5% of Carnot COP, respectively for the given values of parameters. Moreover, the great potential for efficient refrigeration is highlighted by comparing the obtained results with various refrigeration systems. This work lays the foundation for further experimental investigations and opens a new avenue for constructing other novel electrochemical cycles.

AbstractThe engineering background of this paper is the upper protecting seams exploitation of Huangsha Mine, By use of CFD software to analyze the methane delivery law in U type ventilation work face gob. By analyzing the density distribution, pressure distribution, velocity field and mash methane concentration of air-methane mixed gas, obtained the locations of gas drainage hole, and summed up the methane delivery law in U type ventilation work face gob.

This study attempts to explore the bond between Pakistani exports, gross capital formation, energy use and carbon dioxide emission. It uses the data from Pakistan spanning over a longer time horizon of 40 years ranging from 1981 to 2020. The results of ARDL analysis show that Pakistani exports have inverse relationship with CO2 emission in both short as well as long run and the carbon emission reverts to equilibrium at the speed of 54.9%. Increase in carbon emission also lowers export but the causal relationship is only from exports to carbon emission. Energy utilization results in higher carbon emission both in short as well as long run. Based on above findings this study suggests that Pakistan should increase its exports to improve the position of its balance of payment because higher exports do not harm environment in case of Pakistan.

Abstract An energy storage system based on Supercapacitor (SC) for metro network regenerative braking energy is investigated. The control strategy according to the various power requirements in metro line and differing characteristics of these storage devices are proposed to manage the energy and optimize the power supply system performance. In order to estimate the required energy storage system (ESS), line 5 of Beijing metro network is modeled through a novel approach, in different running interval conditions based on the real data obtained from Beijing metro office. A useful method is proposed to predict the instantaneous regenerative energy which is delivered to each substation before applying ESS and based on that the ESS configuration for each substation is determined. A simplified mathematical model of the whole metro network has been developed and the main features of the control strategy have been developed. Numerical simulations show the efficacy of suggested control and the energy saving obtained for metro trains.

Turbine inlet temperature has continuously increased to improve gas turbine performance during the past few decades. Although internal convection cooling and traditional film cooling have contributed significantly to the current achievement, advanced cooling schemes are needed to minimize the coolant consumption and maximize the cooling efficiency for future gas turbines. This paper conducts a comprehensive review of advanced effusive cooling schemes for gas turbine blades. First, the background and the history of turbine blade cooling are introduced. Then, the metrics of effusive cooling efficiency are defined. Next, effusion cooling, impingement/effusion cooling, and transpiration cooling are reviewed. The flow and heat transfer mechanisms of the cooling schemes are emphasized, and the design trends of the cooling schemes are revealed. Finally, the conclusions and future research perspectives are summarized.