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A direct-drive PV pump system based on phase change heat storage is proposed to address the current building energy consumption problem in heating/cooling. The system can solve the problems of unstable solar energy, high battery cost, and short battery service life. Taking a 45m 2 office in Shanghai as the research object, the annual dynamic simulation model of the system is built through TSNSYS. The linear weighted evaluation function method is used for multi-objective optimization analysis of system performance and cost. The results show that the selection scheme with a PV area of 26 m2, a phase change volume of 0.14 m3, and a valley electricity storage ratio of 1 has the best-combined performance and cost of the system.

Background and purpose There is a lack of a reliable outcome prediction model for patients evaluating the feasibility of postoperative adjuvant transarterial chemoembolization (PA-TACE) therapy. Our goal was to develop an easy-to-use tool specifically for these patients. Methods From January 2013 to June 2017, patients with liver cancer from the Liver Center of the First Affiliated Hospital of Chongqing Medical University received postoperative adjuvant Transarterial chemoembolization (TACE) therapy after liver cancer resection. A Cox’s proportional hazards model was established for these patients, followed by internal validation (enhanced bootstrap resampling technique) to further evaluate the predictive performance and discriminance, and compare with other predictive models. The prognostic factors considered included tumour number, maximum tumor diameter, Edmondson-Steiner (ES) grade, Microvascular invasion (MVI) grade, Ki67, age, sex, hepatitis B surface antigen, cirrhosis, Alpha-fetoprotein(AFP), Albumin-bilirubin (ALBI) grade, Child-pugh grade, body mass inex (BMI), Neutrophil-lymphocyte ratio (NLR), Platelet-to-lymphocyte ratio (PLR). Results The end point of the study was overall survival. The median overall survival was 31.8 (95%CI: 30.0-33.6 ) months, with 1-year, 2-year and 3-year survival rates being 96.3%, 84.0% and 75.3%, respectively. Tumour number, MVI grade, and BMI was incorporated into the model, which had good differentiation and accuracy. Internal validation (enhanced bootstrap ) suggested that Harrell’s C statistic is 0.72 (a measure of discrimination, with higher values indicating better discrimination). The model consistently outperforms other currently available models. Conclusions This model may be an easy-to-use tool for screening patients suitable for PA-TACE treatment and guiding the selection of clinical protocols. But further research and external validation are required.

Heat pump water heater can economize dramatic amounts of energy in domestic application. To make full use of hybrid heat source, a solar-air dual series source heat pump water heater (SA-HPWH) is proposed. The refrigerant can get vaporized in two types of evaporators to adjust to variable working conditions. Based on distributed modeling approach, the dynamic model of SA-HPWH system is established. The operational characteristics of the SA-HPWH system have been discussed under different working conditions. The results show that the SA-HPWH system is able to work effectively under low solar irradiation and ambient temperature. The average COP rises from 2.23 to 2.63 with Tair rising from 10 °C to 20 °C. The rise in solar irradiation can lift the evaporating capacity of collector evaporator, while the value in air source evaporator decreases. The overall performance can be enhanced by rising G, and the average COP increases from 2.23 to 2.40 with G increasing from 100W/m2 to 500W/m2. The rise of wind velocity can enhance heat transfer at air side, as well as COP, but the impact is not significant with the wind velocity exceeding 3m/s. In addition, the performance of the SA-SHPWH system can be further improved by utilizing PV/T collector.

Heat pump is a promising approach for low carbon heating/cooling driven by renewable electricity and adapting to multiple heat sources. In this paper, solar-air composite source multi-functional heat pump (SA-CMHP) with the capabilities of space heating, domestic water, space cooling, heat storage, and defrosting has been proposed to provide effective heating/cooling supply solutions for buildings. In SA-CMHP, as the distribution of refrigerant at evaporation side has great impact on its space heating and water heating performance. To optimize its performance under different working conditions, two different control schemes are developed. Mathematic model is established to evaluate and compare the behavior of SA-CMHP under different control schemes. The results reveal that control scheme 1 should be employed when the solar irradiation is insufficient, otherwise, control scheme 2 is more effective for space heating mode. Meanwhile, control scheme 1 should be adopted in water heating mode under different working conditions, as control scheme 1 can effectively reduce the heat loss to environment at evaporation side during the water heating process due to the capability of adaptive regulation of mass flow rate distribution at evaporation side.