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In order to improve the accuracy of load forecasting, eliminate the correlation between multi-meteorological factors and eliminate redundancy, a load forecasting method based on GOA-LSSVM is proposed. Firstly, the principal component analysis is used to express the data dimension reduction and characteristics of load influencing factors, and the main influencing factors are determined. Then, based on the influence of parameter combination of C and G, the LSSVM model parameters are selected by Grasshopper optimization algorithm. The results show that compared with GOA-LSSVM and LSSVM, this algorithm can effectively improve the accuracy of load prediction, and can eliminate the correlation between data redundancy and influencing factors through data reduction and feature representation. It simplifies the complexity of load prediction model, and also the speed of prediction model is improved, which proves the validity and reliability of this algorithm. [ABSTRACT FROM AUTHOR]

KBaY(MoO4)3 : Eu3+ phosphors were synthesized using high temperature solid state method, and their structure, morphology and luminescent properties were characterized by means of X-ray diffraction (XRD), scan electron microscope (SEM), luminescent spectra and luminescent decay curves. The results of XRT) showed that the XRI) patterns of KBaY(MoO4)3 : Eu3+ were consistent with those of pure KBaY(MoO4)3 and the Y<3+ ions could be completely substituted by Eu3+ ions without damaging the structure of KBaY(MoO4)3. The excitation spectra showed that KBaY(MoO4)3 : Eu3+ exhibited an intensive excitation band at 394 nm, which meant the KBaY(MoO4)3 could be effectively excited by NUV LED. According to the luminescent spectra, in the v matrix, the optimum concentration of Eu3+ ions was up to 90%, indicating that the concentration quenching effect was weak for the KBaY(MoO4)3 : Eu3+. The emission intensity decreased with the increasing of temperature. As the temperature reached to 200 °C, the emission intensity of the sample was about 63% of that at 30 °C, and the activation energy of KBaY(MoO4)3 : Eu3+ was calculated to be 0.261eV through fitting the curves of ln(I0C/IT - 1)-1/kT. [ABSTRACT FROM AUTHOR]

In order to solve the common problems in existing solar greenhouses such as simple equipment, poor environmental regulation and cold prevention ability, as well as low land utilization rate and labor productivity, a new type of greenhouse, the assembly type solar double effect greenhouse was built and researched. There are two kinds of structures for the assembly type of the solar double effect greenhouse: internal insulation greenhouse and external insulation greenhouse. Internal insulation warehouse has two layer frames with single layer film covering each layer frame, in addition, one layer of heat preservation quilt is placed between the two layer frames to insulate and preserve heat energy during the night. The external insulation greenhouse has a structure of transparent Polycarbonate sandwich plate as its back half roof and back wall. In winter time, thermal insulation material is filled in the interlayer to preserve heat, in the meantime, the heat preservation quilt is covered on the front half roof, it changed the old way of an opaque back wall and an opaque back half roof in the previous greenhouse. Both the internal and the external insulation greenhouses are fully transparent greenhouses with galvanizing steel structures as framework. A solar energy source heat pump system is assembled in the greenhouse, it includes a solar heat collector, thermal storage pool and the heat pump, with water as its medium, it uses the solar heat collector to convert solar energy into heat energy and it is stored in thermal storage pool. When it is cold, the solar heat collector converts the heat energy stored in the heated water to the greenhouse. When the stored heated water is too cold to provide heat energy, the heat pump is started to convert the low grade heat energy to high grade heat energy, to provide heat energy to the greenhouse. The heat pump can also convert the steam and redundant heat energy in the air into heated water and it is stored in the thermal storage pool, so as to adjust the air temperature and moisture in the greenhouse automatically thus achieving double effects. In this paper, insulation moisture performance and the yield increasing effect are mainly researched for the assembly type of the solar double effect greenhouse. The test was processed from Dec. 2012 to Jan. 2013. The main test indexes are, air minimum temperature, daily average temperature, light intensity, relative air humidity, crops yield per plant and yield per unit area. The test results show: For the internal insulation greenhouse, the minimum temperature of the testing greenhouse was always over 9°C . Compared to the reference greenhouse, during Jan. 2013, the average temperature increased 3.4°C, the monthly average minimum temperature increased 4.0°C, and the monthly average relative air humidity was below 80%, thus achieved a 70% reduction in the incidence of vegetables. For the external insulation greenhouse, the average minimum temperature of the testing greenhouse was 12.5°C, the relative air humidity was below 80%, and the average temperature increased 3.8°C compare to the reference greenhouse. The temperature was 27.7°C higher than outside of the greenhouse (-15.2°C), the yield of the planting vegetables increased 19% - 55%. The conclusion is, the assembly type of the solar double effect greenhouse improved environmental conditions greatly, and improved the capacity of both cold and disease prevention, and increased both production and income. The research and application of this new type of greenhouse are referenced for similar areas in northern China. [ABSTRACT FROM AUTHOR]