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At present, chips urgently need breakthrough development in the power consumption and integration. The chip integrates billions or even tens of billions of electronic components, such as field effect transistor, diode and so on. Therefore, the research and development of new low-power electronic components with smaller size is an effective method to reduce chip power consumption and improve chip integration. In this paper, the ferroelectric field effect transistor (Fe-FET) based on two-dimensional heterostructures α-In2Se3/ZnSe is proposed. Based on the first principle, the program will analyze the stability and band structure of α-In2Se3/ZnSe under different stacking modes. In the heterojunction, the microphysical mechanism of ferroelectric polarization affecting the electronic structure is revealed from the aspects of charge transfer at the interface and the asymmetric surfaces with different work function. Combined with the non-equilibrium Green’s function transport theory, the transport properties of Fe-FET based on their α-In2Se3/ZnSe will be studied. The application will provide sufficient theoretical support for research and development of the device based on α-In2Se3/ZnSe structure.

It is difficult to accurately measure the air exchange rate (AER) in residential and office buildings during occupation via on-site field measurement. The tracer gas method was widely applied to estimate the AER in these buildings, and human metabolic carbon dioxide (CO2) was often used as a tracer gas in different models. This study introduced three models (the ASHRAE model, the ASHRAE China-specific modified model, and the BMR model), which were proposed to estimate the AER based on exhaled CO2. We verified these models by comparing the exhaled CO2-based AER with AER from field measurements using sulfur hexafluoride (SF6) as a tracer gas. We also analyzed the potential factors that could affect the uniformity of the indoor tracer gas distribution. Our results indicate that the ASHRAE China-specific modified model has the best performance with an average deviation of −6.67% and a maximum deviation of −14.6% with multiple measurement points, a stable personnel activity, and proper Parameter settings in a single room in China.

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The indoor thermal environments by using pure porous fabric duct system and orifice & porous fabric duct system in a large space were measured. The PMV and DR (draft of cool air supply) were calculated. The results showed that fabric duct system can meet the requirement of indoor thermal comfort. The vertical temperature was stable under 4m height. The PMV value was between −1∼0.2. In the center of the building, the DR (draft of cool air supply) of orifice & porous fabric duct system was around 10%. Due to the low air supple velocity of pure porous fabric duct system, the DR (draft of cool air supply) was decreased to 1.24%.

The inaccuracies for air velocity measured by Pitots with different diameter have been demonstrated by several experiments. It is defined that the measurement ranges of air velocity by Pitots with different outer diameter. Experiments show that: measurements by Pitot are larger than the true values. The measurement error of air velocity will be smaller if using the Pitot with a smaller outer diameter. The simplified function of correction coefficient and ratio of diameters is deduced by theoretical analysis. The maximum error of correction coefficients is 0.94%, which gained by the simplified function expression is compared with experimental data.