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A reconfigurable loop antenna with two parasitic grounded strips for modern smartphone devices is presented in this paper. The most essential merit of this proposed reconfigurable antenna is that it can keep the intactness of the outer metal rim. In addition, it can generate multiantenna modes. The outer metal rim generates three loop modes and the inner parasite grounded strips can provide two monopole modes. By merging these two types of antenna modes, it can offer two wide bandwidths to cover GSM850/900, DCS/PCS/UMTS2100, and LTE2300/2500 operations with a compact antenna size of 945 mm2. The detailed operating principles and design considerations of this proposed reconfigurable antenna are described. In order to validate this proposed antenna, it was fabricated and tested. The measured antenna efficiencies and gains are satisfied with the requirements for the modern communication devices.

The exhaust heat loss of the power plant boiler can account for more half of the boiler heat loss, exhaust gas temperature is 110~160 °Ccommonly, so the exhaust gas heat can be used to reduce the coal consumption, raise the economic benefits. Before and after the desulfurization tower of a 350 MW unit, there installs two plate heat exchangers, heating condensation water respectively, which can improve the thermal efficiency. With two heat exchangers working under the design conditions, a test was carried out based on a 350 WM unit simulation system in order to test the influence of system for unit operation characteristics. Referring to the data, the investment of the heat exchanger can achieve 2.68 g/kWh coal saving during the non-heating period and 0.2531 g/kWh during the heating period.

The Shijiazhuang six-line tunnel of the Beijing-Shijiazhuang passenger special line is adjacent to a busy and important railway, the Beijing-Guangzhou railway line. Reinforced concrete enclosing piles are adopted during the tunnel excavation cut, and two structures of anchor, reinforced concrete stays and anchor lateral support system are also used. In order to ensure construction and construction process safety, the vibration of the foundation pit piles immediately adjacent to the Beijing-Guangzhou line is tested. In this paper, the time-history curve and spectral curve of the pile is given due to a moving bullet train (Lei, 2003). Analysis of test data provides a useful experience and reference for similar projects in the future.