This study uses the dynamic data envelopment analysis model to evaluate the intertemporal efficiency and the executive efficiency based on fossil fuel CO2 emissions in European Union countries. European Union countries in pursuit of economic growth, taking into account the growth of gross domestic product may result in increased CO2 emissions, countries in order to reduce CO2 emissions to meet the target of the UN climate change conference in Paris 2015, in pursuit of gross domestic product growth and CO2 emission reduction targets. Whether the reduction of CO2 emissions will affect the overall efficiency of the country’s economic growth or not will make gross domestic product a major consideration in carryover variables in this study. This paper analyzes data of 28 selected European countries dating from 2009 to 2013 to study the effects of the undesirable output to the energy efficiency ranking. The variables in the model are the input variables: labor force, real capital stock, and energy consumption and the output variable is the undesirable output of fossil fuel CO2 emissions. In the model, the carryover intermediate activity is real gross domestic product. After the Paris Protocol formally replaced the Kyoto Protocol in 2015, the emphasis of this study is on the future state’s pursuit of economic growth, the gross domestic product as a variable in terms of intertemporal efficiency and using CO2 as a variable of undesirable output to analyze the relationship between national economic development and the greenhouse gas emissions for getting a policy indicator of the environmental protection and economic development.

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Previous studies have mostly focused on the operation management efficiency of medical institutions, but the efficiency levels of treatment and medical personnel are rarely considered simultaneously. Therefore, this paper uses the Modified Undesirable Meta‐two‐stage Dynamic data envelopment analysis (DEA) model to evaluate the efficiency of the administration and the treatment stage of 31 provincial medical and health institutions in China. The research results are as follows: (1) the group average efficiency of the high GDP region is better than the low GDP region after dynamic intertemporal impacts, and (2) most of region's administration stage efficiency is superior to the treatment stage efficiency.

The production of hydrogen with the exhaust energy of an internal combustion engine was investigated in this paper. Steam reforming of methanol is an efficient way to generate hydrogen at relatively low temperature. The reactants of this process are methanol and water, and the hydrogen yield may reach as high as 75% theoretically. However, this is an endothermic reaction, and additional energy has to be provided to this process. If copper oxides and zinc oxides are used as catalyst, the reaction may proceed at the temperature of 270°C. A heat exchanger was designed in this study to use the hot exhaust of a diesel engine to convert methanol to hydrogen. This system is composed of a reformer, a heating chamber, a by-pass valve, and a control valve. Methanol was mixed with pure water at the ratio of 1:1 to form methanol solution. The flow rate of the methanol solution was adjusted according to the engine speed and load such that the thermal energy of engine exhaust may be fully utilized. The reformer is made of copper tubes and compact alumina fins. Pills of catalyst were filled inside copper tubes. Hot exhaust gas flowed through fins and transferred heat to methanol solution. Methanol solution at room temperature was fed into the reformer at a specified rate. It was heated and vaporized inside the copper tube, and then converted to the final products. It was found that in our system the molar fraction of H2 in the reformed gas was 72.6%, while that of CO2 was 23.5%. The exhaust temperature of a diesel engine varies in the range of 250°C~450°C, depending on the load of engine. It is quite sufficient to generate hydrogen with engine exhaust in a methanol reformer. In our system, the hydrogen rate of 17.3 L/min can be obtained in the exhaust pipe of a diesel engine with the displacement volume of 6000c.c. It was found that 49.5% of thermal energy can be recovered, and 92.6% of the recovered energy can be converted. In total, 36.7% of the waste energy can be recovered and stored in the reformed fuel.