ABSTRACT
In order to obtain accurate resonance peaks from surface plasmon resonance (SPR) spectral curves, a reasonable denoising method is of great significance for SPR sensing systems. Therefore, the generalized S-transform is combined with the Bald Eagle Search algorithm (BES) in this study, and a denoising method based on the generalized S-transform optimized by BES is proposed and applied to the denoising processing of the SPR spectrum. First, a fiber SPR sensing system is used to obtain the original noised spectrum; then, the generalized S-transform is performed to obtain the corresponding S-domain spectrum. Next, the denoising threshold λn is optimized by the BES algorithm, which is used to denoise and reconstruct the SPR reflection spectrum. Finally, two fitness functions are evaluated until the optimal denoising threshold λn and denoising effect are obtained. The relevant validation experiments are completed, and the experimental results show that the proposed method has the best denoising performance when p is between 0.5 and 1, and λ is between 1.5 and 2.5. Meanwhile, compared to the other denoising methods, the BES-S method can maintain a relatively stable denoising effect on the SPR spectrum with high or low levels of noise; the average values of root mean square error (RMSE) and signal-to-noise ratio (SNR) are 0.27 and 23.61, respectively. Ranking first in terms of comprehensive denoising performance, it can also maintain the original shape of the SPR spectrum and better reflect its characteristic peak while filtering out noise. This method can overcome the problem of arbitrary selection of basic functions and thresholds in conventional denoising methods, and it can improve the detection accuracy of SPR sensors and provide a new idea for SPR spectrum denoising, which also lays the foundation for the application of substance composition detection based on SPR sensor.
ABSTRACT
Objective To summarize the use of the CT-guided mandibular angle plastic osteotomy.Methods The clinical data of mandibular angle plastic osteotomy were analyzed under the CT navigation in recent 3 years in our department.Thin-slice CT scans of the mandibular angle were performed before the operation.The CT data were input to the system of neuronavigation.The surgical procedures were then taken under the CT navigation.Results All of patients who received this new technology obtained good plastic effects and safe operation.The anatomic location accurately achieched with short operation time and less bleeding during the operation and distinct curative effect and fast recovery after operation.The effects of the treatment were fine.No visible complications occurred.Conclusions The CT navigation could fix accurately on position of important blood vessels and nerves which could be injured accidentally during operation and,of course,the safety of the operation is improved.The CT navigation can also determine the position and quantities of osteotomy from three dimensional angles,reduce effectively the surgical complications and the risk of surgery,reduce the psychological burden of patients efficiently and increase their confidence and credibility to the operation and surgeons.
