Entropy Assessment on Environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the environment.Aiming at the damage of the condense heat to the environment,an entropy of re-source loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were introduced.For the evaluation of the entropies,we developed a new algorithm for the parameter i-dentifieation.called the composite influence coefficient,based on the Least Squares Support Vector Machine method.By simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.025(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).     

高效能半导体器件进展与展望

随着数字时代的不断发展,中国"3060碳战略"目标的确立,绿色低碳成为我国各行业发展主要导向,其中,高效能半导体器件发展应用成为推动汽车电子、电子信息、大数据中心等领域节能降耗的重要趋势.从硅、锗为代表的传统半导体材料到现在以氮化镓、碳化硅为代表的第三代半导体材料,再到以金刚石、氧化镓为代表的超宽禁带半导体材料,支撑半导体器件的性能不断提升,促进射频通信、高功率器件、照明器件等方面革新发展.主要介绍了宽禁带半导体和超宽禁带半导体的研究进展,分析了高效能半导体在射频通讯、汽车电子、航空航天、新型显示等新兴领域的应用前景,总结了目前超宽禁带半导体发展主要面临的难点问题,结合当前相关的研究成果,展望高效能半导体科研、技术及产业的发展趋势,对于我国半导体科技与产业发展都具有重要的指导意义.     

Experimental Study of Performance of Thermoelectric Refrigerator under Different Intensity of Heat Emission

Heat emission and the voltage are the main factors affecting the refrigerating capacity of semicon-ductor refrigerator.Some experiments were designed to obtain their influence on refrigerating capacity of semi-conductor and the interaction between heat emission and the voltage.The results shoW that fixing the heat dissi-pation,there is an optimal working voltage for the semiconductor module;and if improving the heat emission,the refrigerating capacity increases and the optimal voltage becomes larger.This can provide the basis for the op-fimal design of semiconductor refrigeration.