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Satellite Navigation 2020年第1期1卷 68-80页

作者： Xiangdong An xiaolin meng Weiping Jiang GNSS Research Center Wuhan University129 Luoyu RoadWuhan 430079China Nottingham Geospatial Institute University of NottinghamNottingham NG72TUUK.

Precise point positioning(PPP)is famous for its capability of high-precision positioning with just one station as long as the receiver can receive global navigation satellite system(GNSS)*** the rapid development of BDS and Galileo,the number of available satellites for positioning has increased *** addition,GPS III,GLONASS-K,BDS,and Galileo satellites can transmit triple-frequency *** potentials of multi-constellation GNSS PPP requires further analysis on a global ***,we selected 96 multi-GNSS experiment(MGEX)stations with a global distribution and used 1 week’s data to assess the PPP *** results show that the PPP based on multi-frequency raw observations with spatial and temporal constraints has better performance than PPP using dual-frequency ionospheric-free *** main contribution of multi-constellation GNSS PPP is to shorten the convergence *** convergence time for GPS PPP is approximately 40 min,which can be shortened to less than 20 min in multi-GNSS *** convergence,the positioning accuracy of multi-GNSS PPP is improved by 0.5 to 1.0 cm compared with GPS or GLONASS *** positioning accuracy of multi-GNSS could be further improved in the future with the BDS and Galileo precise products of orbits,clock and phase center offset/variation.

关键词： Precise point positioning Multi-frequency and multi-constellation GNSS PPP convergence Multi-GNSS experiment

GNSS gyroscopes:determination of angular velocity and acceleration with very high-rate GNSS

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Satellite Navigation 2024年第1期5卷 74-90页

作者： Yun Shi Peiliang Xu Yuanming Shu xiaolin meng School of Geomatics Xi’an University of Science and TechnologyXi’an710054People’s Republic of China Disaster Prevention Research Institute Kyoto UniversityUjiKyoto611-0011Japan College of Marine Geosciences Ocean University of ChinaQingdaoPeople’s Republic of China School of Instrument Science and Engineering Southeast UniversityNanjing210096People’s Republic of China

Although global navigation satellite systems(GNSS)have been routinely applied to determine attitudes,there exists no literature on determining angular velocity and/or angular acceleration from *** by the invention of computerized accelerometers of the correspondence author and following the success of accurately recovering translational velocity and acceleration waveforms from very high-rate GNSS precise positioning by Xu and his collaborators in 2021,we propose the concept of GNSS gyroscopes and reconstruct angular velocity and acceleration from very high-rate GNSS attitudes by applying regularization under the criterion of minimum mean squared *** major results from the experiments can be summarized in the following:(i)angular velocity and acceleration waveforms computed by applying the difference methods to high-rate GNSS attitudes are too noisy and can be physically not meaningful and numerically *** same can be said about inertial measurement unit(IMU)attitudes,if IMU gyros are not of very high accuracy;(ii)regularization is successfully applied to reconstruct the high-rate angular velocity and acceleration waveforms from 50 Hz GNSS attitudes and significantly outperforms the difference methods,validating the proposed concept of GNSS *** comparing the angular velocity and acceleration results by using the difference methods and regularization,we find that the peak values of angular velocity and acceleration by regularization are much smaller by a maximum factor of 1.57 in the angular velocity to a maximum factor of 8662.53 times in the angular acceleration in the case of high-rate GNSS,and by a maximum factor of 1.26 in the angular velocity to a maximum factor of 2819.85 times in the angular acceleration in the case of IMU,respectively;and(iii)the IMU attitudes apparently lead to better regularized angular velocity and acceleration waveforms than the high-rate GNSS attitudes,which can well be explained by the fact that the

关键词： Angular velocity Angular acceleration High-rate GNSS GNSS attitudes GNSS gyroscopes Regularization

Scheme of adaptive polarization filtering based on Kalman model

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Journal of Systems Engineering and Electronics 2006年第1期17卷 13-18页

作者： Song Lizhong Qi Haiming Qiao xiaolin meng Xiande Inst. of Electronic Engineering Harbin Inst. of Technology Harbin 150001 P. R. China

A new kind of adaptive polarization filtering algorithm in order to suppress the angle cheating interference for the active guidance radar is presented. The polarization characteristic of the interference is dynamically tracked by using Kalman estimator under variable environments with time. The polarization filter parameters are designed according to the polarization characteristic of the interference, and the polarization filtering is finished in the target cell. The system scheme of adaptive polarization filter is studied and the tracking performance of polarization filter and improvement of angle measurement precision are simulated. The research results demonstrate this technology can effectively suppress the angle cheating interference in guidance radar and is feasible in engineering.

关键词： guidance radar polarization adaptive filter Kalman filtering interference suppression.

Assessment of tomographic window and sampling rate efects on GNSS water vapor tomography

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Satellite Navigation 2023年第1期4卷 155-166,I0005页

作者： Fei Yang Yilin Sun xiaolin meng Jiming Guo Xu Gong College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing 100083China College of Architecture and Civil Engineering Beijing University of TechnologyBeijing 100124China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The ground-based Global Navigation Satellite System(GNSS)water vapor tomography is increasingly important in GNSS *** the multi-GNSS and more ground-based GNSS sites can be incorporated into the regional water vapor tomographic model,determining the tomographic window and sampling rate is crucial for the modelling of the water vapor *** two factors afect not only the number of available signal rays from the satellites,but also the number of tomographic voxels crossed by the signal *** study uses Hong Kong as the research area to explore the impact of 12 schemes with diferent tomographic window and sampling rate on the three water vapor tomography methods,including Least squares,Kalman fltering,and Multiplicative Algebraic Reconstruction Technique(MART).Numerical results show that the tomographic results with the three methods get better as the width of the tomographic window decreases and the sampling rate increases in these 12 schemes,and it is found that the Least squares method is most afected by the two factors,followed by Kalman fltering and MART *** is recommended to set a tomographic window width of 10 min and a sampling rate of 300 s in a GNSS water vapor tomographic experiment with dense GNSS site like Hong Kong.

关键词： GNSS meteorology Water vapor Tomography

Development and evaluation of the refined zenith tropospheric delay(ZTD)models

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Satellite Navigation 2021年第1期2卷 296-304页

作者： Fei Yang xiaolin meng Jiming Guo Debao Yuan Ming Chen College of Geoscience and Surveying Engineering China University of Mining and Technology-Beijing100083 BeijingChina Global Geospatial Engineering Ltd. The Sino-UK Geospatial Engineering Centre18 Radford Bridge RoadNottingham NG81NAUK School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China National Geomatics Center of China Beijing 100830China.

The tropospheric delay is a significant error source in Global Navigation Satellite System(GNSS)positioning and *** is usually projected into zenith direction by using a mapping *** is particularly important to establish a model that can provide stable and accurate Zenith Tropospheric Delay(ZTD).Because of the regional accuracy difference and poor stability of the traditional ZTD models,this paper proposed two methods to refine the Hopfield and Saastamoinen ZTD *** is by adding annual and semi-annual periodic terms and the other is based on Back-Propagation Artificial Neutral Network(BP-ANN).Using 5-year data from 2011 to 2015 collected at 67 GNSS reference stations in China and its surrounding regions,the four refined models were *** tropospheric products at these GNSS stations were derived from the site-wise Vienna Mapping Function 1(VMP1).The spatial analysis,temporal analysis,and residual distribution analysis for all the six models were conducted using the data from 2016 to *** results show that the refined models can effectively improve the accuracy compared with the traditional *** the Hopfield model,the improvement for the Root Mean Square Error(RMSE)and bias reached 24.5/49.7 and 34.0/52.8 mm,*** values became 8.8/26.7 and 14.7/28.8 mm when the Saastamoinen model was refined using the two *** exploration is conducive to GNSS navigation and positioning and GNSS meteorology by providing more accurate tropospheric prior information.

关键词： GNSS Tropospheric delay ZTD Refined model ANN

A new receiver clock model to enhance BDS-3 real-time PPP time transfer with the PPP-B2b service

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Satellite Navigation 2023年第1期4卷 1-12,I0002页

作者： Yulong Ge Qing Wang Yong Wang Daqian Lyu Xinyun Cao Fei Shen xiaolin meng School of Marine Science and Engineering Nanjing Normal UniversityNanjing 210023China School of Instrument Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Province Institute of Surveying and Mapping Engineering Nanjing 210013China College of Electronic Engineering National University of Defense TechnologyHefei 230037China School of Geography Nanjing Normal UniversityNanjing 210023China Faculty of Architecture Civiland Transportation EngineeringBeijing University of TechnologyBeijing 100124China State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyCASWuhan 430077China GNSS Research Center Wuhan UniversityWuhan 430079China

A new Precise Point Positioning(PPP)service,called the PPP-B2b service,has been implemented in the BeiDou-3 Navigation Satellite System(BDS-3),which brings new opportunities for time ***,the solution using the traditional PPP method with the PPP-B2b correction still absorbs some unknown errors and needs reconverging when there exist abnormal *** developed a new receiver clock model to improve PPP time transfer using the PPP-B2b *** traditional PPP time transfers using PPP-B2b with BDS-3,Global Positioning System(GPS),and BDS-3/GPS(Scheme1)are compared with the corresponding time transfer with the proposed clock model(Scheme2).The results show that GPS-only PPP is not recommended because of low accuracy of 2 ***-3 or BDS-3/GPS PPP time transfers in Scheme1 can realize about 0.2 ns *** the new clock model is applied,the accuracy can be improved by up to 45%and 39.8%for BDS-3 and BDS-3/GPS PPP,*** proposed clock model can signifcantly improve the short-term frequency stability by 57.4%,but less for the long-term stability.

关键词： PPP-B2b BDS-3 Time transfer Receiver clock model

First results of BDS positioning for LBS applications in the UK

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Satellite Navigation 2021年第1期2卷 111-129页

作者： Yan Xia xiaolin meng Yusong Yang Shuguo Pan Qing Zhao Wang Gao School of Instrument Science and Engineering Southeast UniversityNanjing 210096China Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology Ministry of EducationNanjing 210096China Nottingham Geospatial Institute The University of NottinghamNottingham NG72TUUK Global Geospatial Engineering Ltd./Sino-UK Geospatial Engineering Centre Radford Bridge RoadNottingham NG81NAUK State Key Laboratory of Media Convergence Production Technology and Systems Beijing 100031China School of Transportation Southeast UniversityNanjing 210096China.

The last satellite of BeiDou Navigation Satellite System with Global Coverage(BDS-3)constellation was successfully launched on June 23rd,2020,and the entire system began to provide Positioning,Navigation,and Timing(PNT)services *** evaluated the performance of location services using BDS with a smartphone that can track the Global Navigation Satellite System(GNSS)satellites in Nottingham,*** static and kinematic experiments were conducted in an open meadow and a lakeside route covered by trees,*** results show that BDS has good visibility,and its overall signal carrier-to-noise density ratio(C/N0)is comparable to that of Global Positioning System(GPS).The average C/N0 of BDS-3 satellites with elevation angles above 45°on B1 band is the highest among all systems,reaching 40.0 dB·*** noise level of the BDS pseudorange measurements is within 0.5 m,and it has a good consistency among *** the static experiment,the standard deviations of BDS position-ing in the east,north and up directions are 1.09,1.16,and 3.02 m,respectively,and the R95 value of the horizontal position is 2.88 *** harsh environments,the number of BDS satellites tracked by the smartphone is susceptible to environmental *** bias Root Mean Squares(RMS)in the three directions of the whole kinematic positioning are 6.83,6.68,11.67 m,in which the positioning bias RMS values in a semi-open environment are only 2.81,1.11,3.29 ***,the inclusion of BDS in multiple GNSS systems can significantly improve the positioning *** study intends to provide a reference for the further improvements of BDS global PNT services,particularly for Location-Based Services(LBS).

关键词： BDS Android smartphone Observation quality LBS UK

Peptidetransporter1(PepT1)in fish: Areview

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Aquaculture and Fisheries 2017年第5期2卷 193-206页

作者： Junli Wang Xiao Yan Ronghua Lu xiaolin meng Guoxing Nie College of Life Sciences Henan Normal UniversityXinxiang 453007HenanChina College of Fisheries Henan Normal UniversityXinxiang 453007HenanChina

The Peptide Transporter 1(PepT1)plays an important role in animal protein *** is a lowaffinity/high-capacity,stereoselective transmembrane transporter that mediates the uptake of a fraction of dietary amino acids in their di-and tripeptide ***1 is highly expressed in the intestines of vertebrates and the current studies examining PepT1 function have concentrated mostly on mammals and less emphasis has been placed on protein nutrition in *** the gastrointestinal track,amino acids are absorbed more efficiently in the form of small peptides than as free amino acids suggesting a potential role of PepT1 in the optimization of amino acid absorption which is relevant for fish ***,this review focused on the physiological characteristics,structures,tissue distribution and expression of PepT1 transcripts and regulation of PepT1 protein in fish.

关键词： PepT1 Fish Protein structure Tissue distribution Regulation Gene expression

A versatile 3D-printable hydrogel for antichondrosarcoma,antibacterial,and tissue repair

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Journal of Materials Science & Technology 2023年第5期136卷 200-211页

作者： Wenxiang Zhu Zheng Zhou Yuting Huang Hairong Liu Ning He Xiaolong Zhu Xiaoxiao Han Dengming Zhou Xuanchu Duan Xin Chen Yahui He xiaolin meng Shuai Zhu College of Materials Science and Engineering Hunan UniversityChangsha 410082China College of Biology Hunan UniversityChangsha 410082China State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan UniversityChangsha 410082China Department of Ophthalmology The Second Xiangya HospitalCentral South UniversityChangsha 410011China Aier Glaucoma Institute Changsha 410000China Aier School of Ophthalmology Central South UniversityChangsha 410000China Changsha Aier Eye Hospital Aier Eye Hospital GroupChangsha 410000China

Following operative treatment of chondrosarcoma,post-surgery tissue reconstruction may be confronted with daunting challenges,including the delayed self-repair of defective tissue,tumor recurrence,and bac-terial *** overcome these challenges,a methacrylic anhydride(MA)modified sericin(SerMA)solution mixed with procyanidins(PC)loaded polydopamine(PDA)modified ZIF-8(PC@ZIF-8@PDA)nanoparticles to form a multifunctional PC@ZIF-8@PDA/SerMA hydrogel after exposure under blue *** products with pre-designed shapes were printed out by using the SerMA solution carrying PC@ZIF-8@PDA nanoparticles and chondrocytes,indicating that PC@ZIF-8@PDA/SerMA hydrogels with personalized shapes can be fabricated via 3D *** PC@ZIF-8@PDA/SerMA hydrogel is able to kill chondrosarcoma cells and bacteria,like Staphylococcus aureus(***),and Escherichia coli(***),by its photothermal activity combined with near-infrared radiation(NIR).The PC@ZIF-8@PDA/SerMA hydrogel exhibited an antioxidative activity and a good biocompatibility and was easily monitored by its florescent and photoacoustic *** articular cartilage defects were efficiently repaired by PC@ZIF-8@PDA/SerMA hydrogels with encapsulated corresponding autologous chondrocytes,and mice skin burning wounds were swiftly regenerated by applying this ***,the PC@ZIF-8@PDA/SerMA hydrogel can be potentially applied to the clinic treatment of chondrosarcoma and tissue defect repair after chondrosarcoma resection due to its multifunction in the future.

关键词： Hydrogel Sericin ZIF-8 Chondrosarcoma Cartilage repair

Overall survival associated with surgery,radiotherapy,and chemotherapy in metastatic vulvar cancer:A retrospective cohort study based on the SEER database

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Cancer Pathogenesis and Therapy 2024年第3期2卷 195-204页

作者： xiaolin meng Shuaiqingying Guo Xue Feng Jihui Ai Jie Yang Reproductive Medicine Center Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Department of Gynecological Oncology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430000China National Clinical Research Center for Obstetrics and Gynecology Cancer Biology Research Center(Key Laboratory of the Ministry of Education)Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China

Background:Large cancer registries help analyze the prognosis of rare malignancies,such as advanced vulvar *** study aimed to compare the overall survival(OS)rates of patients with metastatic vulvar cancer who had undergone chemoradiotherapy and radiotherapy alone and identify prognostic factors using data from the Surveillance,Epidemiology,and End Results(SEER)***:In this retrospective cohort study,we used the SEER database to identify patients with metastatic vulvar cancer diagnosed between 2000 and *** score matching was performed to balance the ***–Meier curves and Cox models were used to analyze ***:A total of 685 patients were included and divided into chemoradiotherapy and radiotherapy groups,and 400 patients were included after propensity score *** chemoradiotherapy group had higher OS in the matched cohort(hazard ratio[HR]=0.7367;95%confidence interval[CI]:0.5906–0.9190;P=0.0049)than the radiotherapy group,which was similar to that in the pre-matched cohort(P<0.0001).Patients who had undergone surgery+radiotherapy with or without chemotherapy showed higher OS rates than those who had received radiotherapy with or without chemotherapy for patients aged<75 years and local tumor excision/destruction or surgical removal of the primary site was the recommended surgical choice(P<0.05).Chemoradiotherapy is sufficient for patients 75 years of ***:Patients with metastatic vulvar cancer should undergo surgery if they can tolerate *** chemoradiotherapy should be encouraged because this treatment modality was associated with higher OS than radiotherapy alone.

关键词： Vulvar cancer Metastatic Surveillance,Epidemiology,and End Results (SEER)database Overall survival Radiotherapy