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According to the energy-consuming characteristics of buildings in hot summer and warm winter area, a direct-expansion solar-ground source heat pump system is put forward. This system runs the direct-expansion solar heat pump system in summer and direct-expansion solar-ground source heat pump system in transition season and winter to produce hot water. The article analyses the thermal contribution rates of double-heat sources of the system under various working conditions in different seasons. Results indicate that the total area of solar evaporators matches the power of units and the matching value is 2.18m2/kW. When the average daily total solar radiation is 15.8MJ/m2 in summer, 11.2MJ/m2 in transition season and 11.2MJ/m2 in winter, the unit area heat transfer are respectively about 1.48kW/m2, 1.1kW/ m2 and 0.43kW/m2. The annual solar thermal contribution rate is 46.4% and the annual soil thermal contribution rate is 32%, which can reduce 57.96% quantity of heat absorbing from the soil.

We present a compact printed ultra-wideband (UWB) antenna with a band-notched characteristic. A modified ground plane is introduced to achieve a wide impedance bandwidth from 3 to 13.4 GHz with S11

Annual cold heat adjustment is one of the key problems in the practical application of ground-source heat pump system. According to the energy-consuming characteristics of the building in hot summer and warm winter area zone and engineering practice, the author puts forward the multi-level heat shunt ground source heat pump systems(GSHPS). Reasonable system can be matched according to the characteristics of the cold water chiller and the water source heat pump, which takes full advantages of soil cold/heat source, improves the efficiency of the soil heat exchanger, and balances underground temperature field effectively.