Background Lumbar pedicle screw fixation and fusion are major procedures for treating discogenic low back pain （DLBP）. However, due to its advantages of preserving the segmental motion and biomechanical simulation, ...Background Lumbar pedicle screw fixation and fusion are major procedures for treating discogenic low back pain （DLBP）. However, due to its advantages of preserving the segmental motion and biomechanical simulation, artificial total lumbar disc replacement （TDR） is increasingly popular. Methods From 2007 to 2010, 68 DLBP patients were enrolled. TDR were performed on 34 patients and the other 34 controls underwent the traditional fixation procedure. Qualitative and quantitative evaluations were followed including the changes in range of motion （ROM） and interpedicle height （IPH） at the posterior intervertebral body of operated level, in 6 and 12 months, and 3 years, postoperatively. Results Qualitative results showed satisfying improvement in the two groups after 6 and 12 months, respectively, and the inter-group differences were significant （P 〉0.05）. The results of ROM and IPH have shown significant differences between the TDR and spinal fusion groups （P 〈0.05）. Conclusion With similar clinical improvements as the traditional spinal fusion method, TDR offered significantly better ROM and intervertebral foramen hei.qht.展开更多
This paper presents a new method of High Resolution Range (HRR) profile formation based on Linear Frequency Modulation (LFM) signal fusion of multiple radars with multiple frequency bands. The principle of the multipl...This paper presents a new method of High Resolution Range (HRR) profile formation based on Linear Frequency Modulation (LFM) signal fusion of multiple radars with multiple frequency bands. The principle of the multiple radars signal fusion improving the range resolution is analyzed. With the analysis of return signals received by two radars,it is derived that the phase difference between the echoes varies almost linearly with respect to the frequency if the distance between two radars is neg-ligible compared with the radar observation distance. To compensate the phase difference,an en-tropy-minimization principle based compensation algorithm is proposed. During the fusion process,the B-splines interpolation method is applied to resample the signals for Fourier transform imaging. The theoretical analysis and simulations results show the proposed method can effectively increase signal bandwidth and provide a high resolution range profile.展开更多
文摘Background Lumbar pedicle screw fixation and fusion are major procedures for treating discogenic low back pain （DLBP）. However, due to its advantages of preserving the segmental motion and biomechanical simulation, artificial total lumbar disc replacement （TDR） is increasingly popular. Methods From 2007 to 2010, 68 DLBP patients were enrolled. TDR were performed on 34 patients and the other 34 controls underwent the traditional fixation procedure. Qualitative and quantitative evaluations were followed including the changes in range of motion （ROM） and interpedicle height （IPH） at the posterior intervertebral body of operated level, in 6 and 12 months, and 3 years, postoperatively. Results Qualitative results showed satisfying improvement in the two groups after 6 and 12 months, respectively, and the inter-group differences were significant （P 〉0.05）. The results of ROM and IPH have shown significant differences between the TDR and spinal fusion groups （P 〈0.05）. Conclusion With similar clinical improvements as the traditional spinal fusion method, TDR offered significantly better ROM and intervertebral foramen hei.qht.
文摘This paper presents a new method of High Resolution Range (HRR) profile formation based on Linear Frequency Modulation (LFM) signal fusion of multiple radars with multiple frequency bands. The principle of the multiple radars signal fusion improving the range resolution is analyzed. With the analysis of return signals received by two radars,it is derived that the phase difference between the echoes varies almost linearly with respect to the frequency if the distance between two radars is neg-ligible compared with the radar observation distance. To compensate the phase difference,an en-tropy-minimization principle based compensation algorithm is proposed. During the fusion process,the B-splines interpolation method is applied to resample the signals for Fourier transform imaging. The theoretical analysis and simulations results show the proposed method can effectively increase signal bandwidth and provide a high resolution range profile.
