To achieve continuous demodulation,high precision,and high resolution in the C-band,this paper designs,simulates and prepares a 30-channel array waveguide grating(AWG)based on a silicon dioxide planar optical circuit ...To achieve continuous demodulation,high precision,and high resolution in the C-band,this paper designs,simulates and prepares a 30-channel array waveguide grating(AWG)based on a silicon dioxide planar optical circuit for fiber Bragg grating(FBG)interrogation and couples the prepared AWG with a photodetector array using hybrid integration technology.The test results indicate that the AWG has a good transmission spectrum,a 3 dB bandwidth of 2.15 nm,an insertion loss of approximately 3.6–4.2 dB,and crosstalk of less than−30 dB.The FBG interrogation system can achieve continuous demodulation in the dynamic range of 1521–1569 nm,and realize continuous demodulation in the C-band with a wavelength resolution of 1 pm and a demodulation accuracy of 5.8 pm.This demodulation method provides an optimization direction for researching FBG interrogation systems based on AWGs.展开更多
A 16-channel arrayed waveguide grating(AWG)with an 800 GHz channel spacing in the O-band has been developed and fabricated based on silica planar lightwave circuit(PLC)technology.By extending the wave⁃length allocatio...A 16-channel arrayed waveguide grating(AWG)with an 800 GHz channel spacing in the O-band has been developed and fabricated based on silica planar lightwave circuit(PLC)technology.By extending the wave⁃length allocation from 8 channels to 16 channels as specified in IEEE 802.3bs,we increased the number of chan⁃nels and boosted transmission capacity to meet the 1.6 Tbps and higher-speed signal transmission requirements for future data centers.Through optimizing the AWG structure,it has achieved insertion loss(IL)better than-1.61 dB,loss uniformity below 0.35 dB,polarization-dependent loss(PDL)below 0.35 dB,adjacent channel cross⁃talk under-20.05 dB,ripple less than 0.75 dB,center wavelength offset under 0.22 nm and 1 dB bandwidth ex⁃ceeding 2.88 nm.The AWG has been successfully measured to transmit 53 Gbaud 4-level pulse amplitude modu⁃lation(PAM4)signal per channel and the total transmission speed can reach over 1.6 Tbps.展开更多
BACKGROUND Sarcopenia is a nutrition-related disease and has a profound effect on the longterm overall survival(OS)of patients with gastric cancer.Its diagnostic criterion is critical to clinical diagnosis and treatme...BACKGROUND Sarcopenia is a nutrition-related disease and has a profound effect on the longterm overall survival(OS)of patients with gastric cancer.Its diagnostic criterion is critical to clinical diagnosis and treatment.However,previous research reported widely differing sarcopenia prevalence due to different criteria.AWGS2019 and EWGSOP2 are the two latest and widely adopted criteria.AIM To compare the effects of AWGS2019 and EWGSOP2 on the long-term OS of Chinese gastric cancer patient after radical gastrectomy.METHODS An observational study was conducted from July 2014 to January 2017,which included 648 consecutive gastric cancer patients who underwent radical gastrectomy.The sarcopenia elements(skeletal muscle index,handgrip strength,and gait speed)were measured within 1 mo or 7 d before surgery.The patients were followed at fixed intervals to gain the outcomes.Multivariate Cox regression analysis was performed to determine the association between sarcopenia and the long-term OS of these patients according to the two criteria separately.The predictive performance of the models with AWGS2019 and EWGSOP2 were evaluated by the concordance index(C-index)and area under the time-dependent receiver operating characteristic curve(AUC).The Akaike information criterion(AIC)was applied to compare model fits.RESULTS The prevalence of sarcopenia was 20.5%and 11.3%according to AWGS2019 and EWGSOP2,respectively.Sarcopenia was an independent risk factor for the longterm OS no matter based on AWGS2019 or EWGSOP2,but AWGS2019-sarcopenia in multivariate model had a higher hazard ratio(HR)[2.150(1.547-2.988)]than EWGSOP2-sarcopenia[HR 1.599(1.092-2.339)].Meanwhile,the model with AWGS2019-sarcopenia[C-index 0.773(0.742-0.804);AIC 2193.7;time-dependent AUC 0.812(0.756-0.867)for 1-year OS,0.815(0.778-0.852)for 3-year OS,and 0.809(0.759-0.859)for 5-year OS]had better predictive power and model fits than the model with EWGSOP2-sarcopenia[C-index 0.762(0.729-0.795);AIC 2215.2;timedependent AUC 0.797(0.741-0.854)for 1-year OS,0.804(0.767-0.842)for 3-year OS,and 0.799(0.748-0.850)for 5-year OS].CONCLUSION Sarcopenia is an independent risk factor for the long-term OS in Chinese gastric cancer patients undergoing radical gastrectomy.The prediction model with AWGS2019-sarcopenia has better predictive power and model fits than the prediction model with EWGSOP2-sarcopenia.AWGS2019 may be more appropriate for diagnosing sarcopenia in these Chinese patients than EWGSOP2.展开更多
A 32-channel 50 GHz spaced arrayed-waveguide grating(AWG) with our innovative configuration has been designed and fabricated.The performance of the device has been fully tested by using a system that consists of a tun...A 32-channel 50 GHz spaced arrayed-waveguide grating(AWG) with our innovative configuration has been designed and fabricated.The performance of the device has been fully tested by using a system that consists of a tunable laser light source (TLS), an optical power meter and a polarization controller.The insertion loss (IS) of the device is 4.2-7.4 dB.The crosstalk is about -28 dB.The IS uniformity is less than 3.3 dB.With our configuration,the performance of the device has been enhanced effectively and the difficulty in alignment process has been decreased obviously.展开更多
Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and to...Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and total measurement range of AWG-based FBG interrogation systems are constrained by the output properties of AWG. We proposed an AWG-based large dynamic range interrogation system. The temperature dependence of AWG is exploited to achieve continuous interrogation. The test results show that the interrogation system has a dynamic range of 28.67 nm, an interrogation accuracy better than 25 pm, and a wavelength resolution of 6 pm.展开更多
基金supported by the National Natural Science Foundation of China(No.62205030)the R&D Program of Beijing Municipal Education Commission(No.KM202211232019).
摘要To achieve continuous demodulation,high precision,and high resolution in the C-band,this paper designs,simulates and prepares a 30-channel array waveguide grating(AWG)based on a silicon dioxide planar optical circuit for fiber Bragg grating(FBG)interrogation and couples the prepared AWG with a photodetector array using hybrid integration technology.The test results indicate that the AWG has a good transmission spectrum,a 3 dB bandwidth of 2.15 nm,an insertion loss of approximately 3.6–4.2 dB,and crosstalk of less than−30 dB.The FBG interrogation system can achieve continuous demodulation in the dynamic range of 1521–1569 nm,and realize continuous demodulation in the C-band with a wavelength resolution of 1 pm and a demodulation accuracy of 5.8 pm.This demodulation method provides an optimization direction for researching FBG interrogation systems based on AWGs.
基金Supported by the National Key Research and Development Program of China(2021YFB2800201)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB43000000)。
摘要A 16-channel arrayed waveguide grating(AWG)with an 800 GHz channel spacing in the O-band has been developed and fabricated based on silica planar lightwave circuit(PLC)technology.By extending the wave⁃length allocation from 8 channels to 16 channels as specified in IEEE 802.3bs,we increased the number of chan⁃nels and boosted transmission capacity to meet the 1.6 Tbps and higher-speed signal transmission requirements for future data centers.Through optimizing the AWG structure,it has achieved insertion loss(IL)better than-1.61 dB,loss uniformity below 0.35 dB,polarization-dependent loss(PDL)below 0.35 dB,adjacent channel cross⁃talk under-20.05 dB,ripple less than 0.75 dB,center wavelength offset under 0.22 nm and 1 dB bandwidth ex⁃ceeding 2.88 nm.The AWG has been successfully measured to transmit 53 Gbaud 4-level pulse amplitude modu⁃lation(PAM4)signal per channel and the total transmission speed can reach over 1.6 Tbps.
基金Supported by Zhejiang Provincial Health Department Medical Support Discipline-Nutrition,No.11-ZC24Wenzhou Municipal Science and Bureau,No.Y2020732.
摘要BACKGROUND Sarcopenia is a nutrition-related disease and has a profound effect on the longterm overall survival(OS)of patients with gastric cancer.Its diagnostic criterion is critical to clinical diagnosis and treatment.However,previous research reported widely differing sarcopenia prevalence due to different criteria.AWGS2019 and EWGSOP2 are the two latest and widely adopted criteria.AIM To compare the effects of AWGS2019 and EWGSOP2 on the long-term OS of Chinese gastric cancer patient after radical gastrectomy.METHODS An observational study was conducted from July 2014 to January 2017,which included 648 consecutive gastric cancer patients who underwent radical gastrectomy.The sarcopenia elements(skeletal muscle index,handgrip strength,and gait speed)were measured within 1 mo or 7 d before surgery.The patients were followed at fixed intervals to gain the outcomes.Multivariate Cox regression analysis was performed to determine the association between sarcopenia and the long-term OS of these patients according to the two criteria separately.The predictive performance of the models with AWGS2019 and EWGSOP2 were evaluated by the concordance index(C-index)and area under the time-dependent receiver operating characteristic curve(AUC).The Akaike information criterion(AIC)was applied to compare model fits.RESULTS The prevalence of sarcopenia was 20.5%and 11.3%according to AWGS2019 and EWGSOP2,respectively.Sarcopenia was an independent risk factor for the longterm OS no matter based on AWGS2019 or EWGSOP2,but AWGS2019-sarcopenia in multivariate model had a higher hazard ratio(HR)[2.150(1.547-2.988)]than EWGSOP2-sarcopenia[HR 1.599(1.092-2.339)].Meanwhile,the model with AWGS2019-sarcopenia[C-index 0.773(0.742-0.804);AIC 2193.7;time-dependent AUC 0.812(0.756-0.867)for 1-year OS,0.815(0.778-0.852)for 3-year OS,and 0.809(0.759-0.859)for 5-year OS]had better predictive power and model fits than the model with EWGSOP2-sarcopenia[C-index 0.762(0.729-0.795);AIC 2215.2;timedependent AUC 0.797(0.741-0.854)for 1-year OS,0.804(0.767-0.842)for 3-year OS,and 0.799(0.748-0.850)for 5-year OS].CONCLUSION Sarcopenia is an independent risk factor for the long-term OS in Chinese gastric cancer patients undergoing radical gastrectomy.The prediction model with AWGS2019-sarcopenia has better predictive power and model fits than the prediction model with EWGSOP2-sarcopenia.AWGS2019 may be more appropriate for diagnosing sarcopenia in these Chinese patients than EWGSOP2.
基金Project supported by Nation Key Basic R&D Plan of China(G2000036602) ,and the National Natural Science Foundation ofChina(No.69889701)
摘要A 32-channel 50 GHz spaced arrayed-waveguide grating(AWG) with our innovative configuration has been designed and fabricated.The performance of the device has been fully tested by using a system that consists of a tunable laser light source (TLS), an optical power meter and a polarization controller.The insertion loss (IS) of the device is 4.2-7.4 dB.The crosstalk is about -28 dB.The IS uniformity is less than 3.3 dB.With our configuration,the performance of the device has been enhanced effectively and the difficulty in alignment process has been decreased obviously.
基金supported by the National Natural Science Foundation of China(No.62205030)the R&D Program of Beijing Municipal Education Commission(No.KM202211232019)。
摘要Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and total measurement range of AWG-based FBG interrogation systems are constrained by the output properties of AWG. We proposed an AWG-based large dynamic range interrogation system. The temperature dependence of AWG is exploited to achieve continuous interrogation. The test results show that the interrogation system has a dynamic range of 28.67 nm, an interrogation accuracy better than 25 pm, and a wavelength resolution of 6 pm.