Objective To provide the hardware system of EIT with an excellent direct current(DC) power source. Methods The spectrums of the outputs of DC power source and the driving source were analyzed by means of Spectrum Analyzer- E4408B when EIT system was respectively powered by battery, linear power source and switching power source. Based on the numbers and power levels of the spurs of the three power sources and the numbers and power levels of the interferences within the driving source, the influence of the three power sources on the error of measuring was estimated. Meanwhile the EIT system did data acquisition, the overall signal-to-noise-ratio(SNR) of the three power sources at the 18 frequencies were calculated and the influence of the three power sources on the error of measuring was judged. Results With respect to the numbers and power levels of the interferences within the driving source when EIT was powered respectively by the three power sources, the battery output 6 interferences, the highest power of which achieved -78.25 dBm; the linear power source output 6 interferences, the highest power of which achieved -67.11 dBm; the switching power source output 15 interferences, the highest power of which achieved -35.83 dBm. The overall SNRs of the battery at the 18 driving frequencies were higher than that of the linear power source, and the overall SNRs of the linear power source were higher than that of the switching power source. Conclusion The power mode of battery is the best for the hardware of EIT among the three power sources.

Purpose/Significance To expound the development status,difficulties and challenges of smart hospital in China,so as to pro-vide references for the subsequent related research.Method/Process By using the methods of bibliometrics and literature review,the definition of smart hospital is summarized and feasible suggestions on the construction of smart hospital are put forward.Result/Conclusion Smart hospital in China has initially established a"trinity"structural framework of smart healthcare,smart service and smart management,playing a positive role in improving patient satisfaction and promoting high-quality development of hospitals.It is necessary for the government,hospitals,social capital and other multi-party cooperation to jointly promote the construction of smart hospital in China and better protect people's health.