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A new cool-tip radiofrequency (RF) ablation therapeutic instrument based on impedance control algorithm is introduced in this paper. The equipment is composed of hardware system and software system. The RF power output and real time data acquisition are completed by the hardware system, while the software is used mainly to finish the control of the ablation range, the core of which is impedance control algorithm, and it also used to complete the display of the real time data in the course of the experiment. The impedance algorithm has solved the problem of impedance increased rapidly during the RF ablation, which has also expanded the scope of ablation. The pig liver experiments showed that the impedance control algorithm had strong adaptability. It also obtained a result of ablation range up to 3.5-4.5 cm single needle. It has the high clinical practical value of one-time inactivation of 3-5 cm tumor.

Spectrum sensing is a key technical challenge for cognitive radio (CR). It is well known that multi-cycle cyclostationarity (MC) detector is a powerful method for spectrum sensing. However, conventional MC detector is difficult to implement due to its high computational complexity. This paper pays attention to the fact that the computation complexity can be reduced by simplifying the test statistic of conventional MC detector. Based on this simplification process, an improved MC detector is proposed. Compared with the conventional one, the proposed detector has the low-computational complexity and high-accuracy on sensing performance. Subsequently, the sensing performance of proposed detector is investigated over Nakagami-m fading channels. Furthermore, the SLC diversity is introduced to improve the detection reliability over fading channels. The corresponding closed-form expression of average detection probability is derived by using the moment generation function (MGF) approach. Finally, simulation results verify the efficiency and accuracy of proposed detector, which contributes to a performance gain of approximately 3dB for 2-branches SLC even if serious Nakagami-m fading exist.

There are three improvements of the method for image decomposition based on the VO model proposed by Vese and Osher. One is to introduce an edge detecting function to induct diffusion; one is to use the module of a wavelet transform to instead of the traditional gradient to detect edge; and the other is to update the image during iteration. The improved method overcomes the situation like fuzzy edge and staircase effect in some sense, improves the quality and efficiency of decomposition. The experimental results prove that the improved method protects the edge of cartoon and information of texture effectively.