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A compact multiband bow-tie dipole slot antenna fed by coplanar waveguide (CPW) is proposed in this paper. Multiple resonant mode technique and notch-band technique have been combined in this design to form triple-band operation just by adding single elements. Based on this, a pair of hairpin-shaped branches is implemented on each arm of the bow-tie slot antenna. A notch- band property is achieved compared with the original wideband bow-tie antenna (without branches). Meanwhile, a new lower resonant frequency is obtained by using this kind of structure, which means that the size is compact in nature, and the triple-band operation is achieved. The notch-band and lower resonant frequency can be tuned by changing the length of the branch. The parameters of the antenna, including reflection coefficients, current distributions, radiation patterns and gain, are achieved by numerical simulations and measurements. The results indicate that the slot size of the proposed antenna is 52. 4m m× 22.3 mm, and the proposed antenna can offer triple-band operation at 2.39-2.50 GHz (4.5%), 3.38-3.79 GHz (11.4%) and 4.87-6.23 GHz (24.5%), which is suitable for WLAN in the 2.4/5.2/5.8-GHz band and WiMAX in the 3.5/5.5-GHz bands.

The shield tunnel of the Kunming subway crosses beneath the Kun-Shi Railway. Due to the high requirements of railway track for settlement control, this article proposes the following technical measures for controlling the settlement based on the analysis of risks arising from the shield crossing railway: (1) Reinforcing the stratum of the region crossed by the shield in advance to achieve high stability; (2) Using a reinforced segment for the shield tunnel and increasing reserved grouting holes for construction; (3) Reasonably configuring resources, optimizing construction parameters, strengthening monitoring and information management during the shield crossing. In strict accordance with the construction plan, the shield successfully and safely crossed beneath the Kun-Shi Railway; this provides experience that can be used in similar projects in the future.

A compact modified rectenna for Ka band Wireless Power Transmission is proposed. The rectenna is composed of square patch antenna, an input filter, a diode, an output filter and a load. By adding two microstrip lines at 35GHz and 70GHz in the output port of the rectifying circuit, the fundamental frequency and two-order harmonic frequency have been restrained effectively. Because of this, the rectifying circuit got a higher simulating conversion efficiency of 68.5% when the input power is 20dBm and load is 100 Ohm. At last, we got a measured result, the conversion efficiency reach to 64%.

This article reviewed the literatures in this area over the past 5 years according to three parts: simple traditional Chinese medicine external application, combination of traditional Chinese medicine and Western medicine, combination of traditional Chinese medicine and physical therapy, and came to several effective prescriptions.