With the rapid advancement of human economic levels and modern civilization,the automobile manufacturing industry is increasingly confronted with challenges related to energy scarcity and environmental pollution.Low c...With the rapid advancement of human economic levels and modern civilization,the automobile manufacturing industry is increasingly confronted with challenges related to energy scarcity and environmental pollution.Low carbon emissions and energy savings have become the main focus of automotive development.Under the influence of government incentives,the sales of household electric vehicles(EVs)have increased significantly,although they still represent a small share of the overall car market.To examine the factors influencing consumer purchases of household EVs,this report integrates both qualitative and quantitative analyses,controlling for single variables.Using linear regression,an empirical analysis was conducted on 18 BYD models with varying ranges and prices.The results indicate a strong positive correlation between driving range,selling price,and EV sales.Looking ahead,the development of new energy vehicles should prioritize longer ranges,high-quality features,and cost-effective performance.展开更多
The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and grow...The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and growth interruption on the electrical properties are investigated by changing the Si-cell temperature, doping time and growth process. It is found that the optimal Si ^-doping concentration （Nd） is about 5.0 x 1012 cm-2 and the use of growth interruption has a dramatic effect on the improvement of electrical properties. The material structure and crystal interface are analyzed by secondary ion mass spectroscopy and high resolution transmission elec- tron microscopy. An InGaAs/InAiAs/InP HEMT device with a gate length of lOOnm is fabricated. The device presents good pinch-off characteristics and the kink-effect of the device is trifling. In addition, the device exhibits fT = 249 GHa and fmax 〉 400 GHz.展开更多
文摘With the rapid advancement of human economic levels and modern civilization,the automobile manufacturing industry is increasingly confronted with challenges related to energy scarcity and environmental pollution.Low carbon emissions and energy savings have become the main focus of automotive development.Under the influence of government incentives,the sales of household electric vehicles(EVs)have increased significantly,although they still represent a small share of the overall car market.To examine the factors influencing consumer purchases of household EVs,this report integrates both qualitative and quantitative analyses,controlling for single variables.Using linear regression,an empirical analysis was conducted on 18 BYD models with varying ranges and prices.The results indicate a strong positive correlation between driving range,selling price,and EV sales.Looking ahead,the development of new energy vehicles should prioritize longer ranges,high-quality features,and cost-effective performance.
基金Supported by the National Natural Science Foundation of China under Grant No 61434006
文摘The InGaAs/InAIAs/InP high electron mobility transistor （HEM：F） structures with lattice-matched and pseudo- morphic channels are grown by gas source molecular beam epitaxy. Effects of Si ^-doping condition and growth interruption on the electrical properties are investigated by changing the Si-cell temperature, doping time and growth process. It is found that the optimal Si ^-doping concentration （Nd） is about 5.0 x 1012 cm-2 and the use of growth interruption has a dramatic effect on the improvement of electrical properties. The material structure and crystal interface are analyzed by secondary ion mass spectroscopy and high resolution transmission elec- tron microscopy. An InGaAs/InAiAs/InP HEMT device with a gate length of lOOnm is fabricated. The device presents good pinch-off characteristics and the kink-effect of the device is trifling. In addition, the device exhibits fT = 249 GHa and fmax 〉 400 GHz.
