Research on the Collinear Equation Model of Visual Positioning Based on Visible Light Communication

A positioning method based on visible light communication is proposed, which receiving visible light information by low-resolution photodiode array and receiving visual information by the front camera of mobile phone. The terminal position is determined by matching spot information provided by photodiode array with visual information and position information provided by visible light communication. A collinear equation model is derived which based on mobile phone front camera. A hardware-in-loop simulation has been conducted to verify the collinear equation. The three-dimensional positioning error is on the level of decimeter. Moreover, the main factors which affect the positioning accuracy are analyzed in order to further improve the positioning accuracy

Research on the Collinear Equation Model of Visual Positioning Based on Visible Light Communication

A positioning method based on visible light communication is proposed, which receiving visible light information by low-resolution photodiode array and receiving visual information by the front camera of mobile phone. The terminal position is determined by matching spot information provided by photodiode array with visual information and position information provided by visible light communication. A collinear equation model is derived which based on mobile phone front camera. A hardware-in-loop simulation has been conducted to verify the collinear equation. The three-dimensional positioning error is on the level of decimeter. Moreover, the main factors which affect the positioning accuracy are analyzed in order to further improve the positioning accuracy

18F‐FDG PET/CT predicts the role of neoadjuvant immunochemotherapy in the pathological response of esophageal squamous cell carcinoma

Abstract Background This study aimed to investigate the predictive value of 18F‐FDG PET/CT for pathological response after neoadjuvant immunochemotherapy (NICT) in patients with esophageal squamous cell carcinoma (ESCC). Methods The clinical data of 54 patients with ESCC who underwent two cycles of NICT followed by surgery were retrospectively analyzed. NICT consisted of PD‐1 blockade therapy combined with chemotherapy. 18F‐FDG PET/CT scans were performed before and after NICT. The pathological results after surgery were used to assess the degree of pathological response. The scan parameters of 18F‐FDG PET/CT and their changes before and after NICT were compared with the pathological response. Results Among the 54 patients, 10 (18.5%) achieved complete pathological response (pCR) and 21 (38.9%) achieved major pathological response (MPR). The post‐NICT scan parameters and their changes were significantly associated with the pathological response. In addition, the values of the changes in the scanned parameters before and after treatment can further predict the pathological response of the patient. Conclusion 18F‐FDG PET/CT is a useful tool to evaluate the efficacy of NICT and predict pathological response in patients with ESCC. The post‐NICT scan parameters and their changes can help identify patients who are likely to achieve pCR or MPR

Credible Navigation Algorithm for GNSS Attack Detection Using Auxiliary Sensor System

In order to effectively reduce the impact of Global Navigation Satellite System (GNSS) attacks while providing mobile terminals with credible navigation and positioning results, this paper proposes a credible navigation algorithm for GNSS attack detection using an auxiliary sensor system. Based on a credible Kalman filter and measurement information provided by the auxiliary sensor system on mobile terminals, the proposed algorithm can verify the credibility of the GNSS positioning result and determine whether it has suffered from a GNSS attack using the credible verification window and the credible verification threshold. According to the verification results, the algorithm can adaptively select an updated model for measurement correction and achieve a credible navigation result. The algorithm proposed in this paper has been verified on a self-developed mobile terminal, and the experimental results show that the algorithm can provide credible navigation and positioning services for mobile terminals in the context of GNSS attacks

Photomechanically Controlled Encapsulation and Release from pH-Responsive and Photoresponsive Microcapsules

Poly­(acrylic acid)/azobenzene microcapsules were obtained through distillation precipitation polymerization and the selective removal of silica templates by hydrofluoric acid etching. The uniform, robust, and monodisperse microcapsules, confirmed by transmission electron microscopy and scanning electron microscopy, had reversible photoisomerization under ultraviolet (UV) and visible light. Under UV irradiation, azobenzene cross-linking sites in the main chain transformed from the trans to cis isomer, which induced the shrinkage of microcapsules. These photomechanical effects of azobenzene moieties were applied to the encapsulation and release of model molecules. After loading with rhodamine B (RhB), the release behaviors were completely distinct. Under steady UV irradiation, the shrinkage adjusted the permeability of the capsule, providing a novel way to encapsulate RhB molecules. Under alternate UV/visible light irradiation, a maximal release amount was reached due to the continual movement of shell networks by cyclic trans–cis photoisomerization. Also, microcapsules had absolute pH responsiveness. The diffusion rate and the final release percentage of RhB both increased with pH. The release behaviors under different irradiation modes and pH values were in excellent agreement with the Baker–Lonsdale model, indicating a diffusion-controlled release behavior. Important applications are expected in the development of photocontrolled encapsulation and release systems as well as in pH-sensitive materials and membranes