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A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

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Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： shan hu Hongbo ZHAO Chen ZhuANG School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban ***-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between ***,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different *** interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle *** demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in *** fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution *** WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity *** tests involving four vehicles were conducted in urban *** results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

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Effectivity and safety of trifocal intraocular lenses and capsular tension rings implantation for cataract patients with axial high myopia

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 499-508页

作者： shan hua Qiu-Xia Xie hu wang Jing-Xiang Zhong Dongguan Aier Eye Hospital Jinan UniversityDongguan 523106Guangdong ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Jinan UniversityGuangzhou 510630Guangdong ProvinceChina Department of Ophthalmology the Sixth Affiliated Hospital of Jinan UniversityDongguan 523576Guangdong ProvinceChina

●AIM:To assess effectivity and safety of trifocal intraocular lenses(IOLs)and capsular tension rings in treating cataract patients with axial high myopia.●METHODS:A prospective nonrandomized controlled clinical trial was *** 98 eyes(74 patients)who underwent femtosecond laser-assisted cataract surgery(FLACS)with trifocal IOLs were enrolled in the study and followed up for 2y after surgery:46 eyes(33 patients)with capsular tension ring implantation in the long axial lengths(AL)group(260.05).The dysfunctional lens index and total modulation transfer function(MTF)average height were similar between the two *** postoperative internal coma aberrations in the axial high myopia eyes were significantly higher than that in the normal AL group(P<0.05).The total satisfaction score in the long AL group(91.32±2.76)was slightly higher than that in the normal AL group(90.36±3.47),but there was no difference(P=0.136).A statistically negative correlation was found between corrected distance visual acuity(CDVA)and dysfunctional lens index(r=-0.382,P=0.009),and between CDVA and the total MTF average height(r=-0.374,P=0.01).But there was no significant correlation between CDVA and total satisfaction score(r=0.059,P=0.696).Postoperative complications mainly presented as posterior capsular opacity(PCO),retinal detachment and cystoid macular *** was no difference in the incidenc

关键词： trifocal intraocular lenses capsular tension ring axial high myopia cataract visual quality

NextPolish2:A Repeat-aware Polishing Tool for Genomes Assembled Using HiFi Long Reads

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 105-109页

作者： Jiang hu Zhuo wang Fan Liang shan-Lin Liu Kai Ye De-Peng wang School of Automation Science and Engineering Faculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China GrandOmics Biosciences Beijing 102206China Department of Entomology College of Plant ProtectionChina Agricultural UniversityBeijing 100193China

The high-fidelity(HiFi)long-read sequencing technology developed by PacBio has greatly improved the base-level accuracy of genome ***,these assemblies still contain base-level errors,particularly within the error-prone regions of HiFi long *** genome polishing tools usually introduce overcorrections and haplotype switch errors when correcting errors in genomes assembled from HiFi long ***,we describe an upgraded genome polishing tool-NextPolish2,which can fix base errors remaining in those“highly accurate”genomes assembled from HiFi long reads without introducing excessive overcorrections and haplotype switch *** believe that NextPolish2 has a great significance to further improve the accuracy of telomere-to-telomere(T2T)***2 is freely available at https://***/Nextomics/NextPolish2.

关键词： Telomere-to-telomere Genome assembly Genome polishing Error correction HiFi long read

Microlensing bias on the detection of strong lensing gravitational wave

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 156-165页

作者： Xikai shan Xuechun Chen Bin hu Guoliang Li Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

Identifying strong lensing gravitational wave(SLGW)events is of utmost importance in astrophysics as we approach the historic first detection of SLGW amidst the growing number of gravitational wave(GW)***,one crucial method for identifying SLGW signals involves assessing the overlap of parameters between two ***,the distribution of discrete matter,such as stars and sub-halos,within the strong lensing galaxy can imprint a wave optical(WO)effect on the SLGW *** frequency dependent imprints introduce biases in parameter estimation and impact SLGW *** this study,we assess the influence of the stellar microlensing field embedded in a strong lensing *** findings demonstrate that the WO effect reduces the detection efficiency of SLGW by 5%-50%for various false alarm probabilities per pair(FAPper pair).Specifically,at an FAPper pairof 10^(-5),the detection efficiency decreases from~10%to~5%.Consequently,the presence of the microlensing field can result in missing half of the strong lensing ***,the microlensing WO effect introduces a noticeable bias in intrinsic parameters,particularly for chirp mass and mass ***,it has tiny influence on extrinsic *** all parameters,~30%of events exhibit a 1σparameter bias,~12%exhibit a 2σparameter bias,and~5%exhibit a 3σparameter bias.

关键词： gravitational wave gravitational strong lensing gravitational micro lensing wave optical effect

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Estimates of net primary productivity and actual evapotranspiration over the Tibetan Plateau from the Community Land Model version 4.5 with four atmospheric forcing datasets

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Journal of Plant Ecology 2024年第4期17卷 70-89页

作者： shan Lin Kewei huang Xiangyang Sun Chunlin Song Juying Sun Shouqin Sun Genxu wang Zhaoyong hu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China hubei Key Laboratory of Basin Water Security Changjiang SurveyPlanningDesign and Research Co.Ltd.Wuhan 430010China Research Unit Forest Dynamics Swiss Federal Research Institute for ForestSnow and Landscape Research WSLBirmensdorf 8903Switzerland

The accuracy of the simulation of carbon and water processes largely relies on the selection of atmospheric forcing datasets when driving land surface models(LSM).Particularly in high-altitude regions,choosing appropriate atmospheric forcing datasets can effectively reduce uncertainties in the LSM ***,this study conducted four offline LSM simulations over the Tibetan Plateau(TP)using the Community Land Model version 4.5(CLM4.5)driven by four state-of-the-art atmospheric forcing *** performances of CRUNCEP(CLM4.5 model default)and three other reanalysis-based atmospheric forcing datasets(***,GSWP3 and WFDEI)in simulating the net primary productivity(NPP)and actual evapotranspiration(ET)were evaluated based on in situ and gridded reference *** with in situ observations,simulated results exhibited determination coefficients(R2)ranging from 0.58 to 0.84 and 0.59 to 0.87 for observed NPP and ET,respectively,among which GSWP3 and ITPCAS showed superior *** the plateau level,CRUNCEP-based simulations displayed the largest bias compared with the reference NPP and ***3-based simulations demonstrated the best performance when comprehensively considering both the magnitudes and change trends of TP-averaged NPP and *** simulated ET increase over the TP during 1982-2010 based on ITPCAS was significantly greater than in the other three simulations and reference ET,suggesting that ITPCAS may not be appropriate for studying long-term ET changes over the *** results suggest that GSWP3 is recommended for driving CLM4.5 in conducting long-term carbon and water processes simulations over the *** study contributes to enhancing the accuracy of LSM in water-carbon simulations over alpine regions.

关键词： land surface model carbon cycle water cycle high altitude Community Land Model version 4.5

Nanoindentation behavior and creep-induced cracking of long-term crept austenitic steel at 650℃

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Journal of Iron and Steel Research International 2024年第2期31卷 464-474页

作者： Zhen Zhang Yu-hang Duan Shuai wang Jin-shan Chen An-zhe wang Xiang-yang Mao Yuan-ji Shi Jie Zhang Ming Liu Zheng-fei hu School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing211167JiangsuChina Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211167JiangsuChina Jiangsu Wind Power Engineering Technology Center Nanjing210023JiangsuChina Nanjing Vocational University of Industry Technology Nanjing210023JiangsuChina Baoshan Iron&Steel Co. Ltd.Shanghai201900China Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116FujianChina School of Materials Science and Engineering Tongji UniversityShanghai201804China

The grain boundary(GB)damage of long-term crept HR3C(25Cr–20Ni–Nb–N)austenitic steel with solid solution state was investigated by nanoindentation test accompanied with in-situ electron back-scattered *** corresponding microstructure was characterized by scanning electron microscopy and transmission electron *** show that the increase in nanoindentation hardness at the GBs and triple grain junctions may be related to the dislocation accumulation and carbide growth during the *** M23C6 and dislocations piling-up at the GB accelerate the nucleation and coalescence of creep cavity along the *** nanoindentation hardness in grains varies with orientation of the stress *** orientation difference of neighbor grains may induce local high geometrically necessary dislocation densities and strain gradients near the GB,consequently causing stress concentration and subsequent crack growth at specific GBs.

关键词： Austenitic steel Creep Nanoindentation Grain orientation Creep-induced cracking

Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： Jian-Guo Li Bai-shan hu Shuang Zhang Fu-Rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

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Distribution, burial fluxes and carbon sink effect of sedimentary organic carbon in the eastern China seas

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Science China Earth Sciences 2024年第10期67卷 3062-3082页

作者： Xuefa SHI Bin WU Shuqing QIAO Zhengquan YAO Limin hu Yazhi BAI shan hu Jie SHENG Yanguang LIU Shengfa LIU Kunshan wang Jianjun ZOU Key Laboratory of Marine Geology and Metallogeny First Institute of Oceanography Ministry of Natural Resources Laboratory for Marine Geology Qingdao Marine Science and Technology Center Key Laboratory of Deep Sea Mineral Resources Development Shandong Province (Preparatory) Key Laboratory of Submarine Geosciences and Technology College of Marine Geosciences Ocean University of China

The ocean is the largest active carbon reservoir on Earth. Organic carbon（OC）, as the primary species of carbon sequestration in the ocean, plays an important role in the global carbon cycle through its deposition and burial. In this study,sedimentary OC data from 5796 stations, together with relevant geochemical and sedimentological parameters in the Bohai Sea,Yellow Sea, and East China Sea（BYES） were used to summarize and elucidate the distribution and burial patterns of sedimentary OC, and assess carbon sink effect of sedimentary OC burial. The results show that the OC content in the sediments of the BYES ranges from 0.00% to 2.12%, with an average content of 0.47%±0.26%. OC content is significantly correlated with finegrained sediments, with an average OC content in mud areas being 39% higher than that in non-mud areas. Modern OC buried in the BYES are mainly deposited in 7 major mud areas, with a total sedimentary OC burial flux of approximately 8.20 Mt C yr–*** them, the burial flux of biospheric OC is 6.92 Mt C yr–1, equivalent to the OC consumption amount of silicate weathering of the 9 major river basins in the eastern China. In its natural state, the annually sequestered OC in the sediments of the eastern China seas is equivalent to 25.37 Mt of atmospheric CO2, indicating a significant carbon sink effect. The distribution and burial of terrigenous OC in the BYES are mainly influenced by the large river inputs and complex marine hydrodynamic environment,while human activities such as dam construction have significantly altered the OC burial in these coastal mud areas.

关键词： Sedimentary organic carbon Burial flux Carbon sink effect Carbon cycle Eastern China seas

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Pleomorphic rhabdomyosarcoma of the vagina: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2396-2403页

作者： Pan Xu shan-shan Ling E hu Bi-Xia Yi Department of Gynecology The Affiliated Jinhua Hospital of Wenzhou Medical UniversityJinhua 321000Zhejiang ProvinceChina Zhejiang University School of Medicine Hangzhou 310006Zhejiang ProvinceChina

BACKGROUND Rhabdomyosarcoma(RMS)of the vagina in postmenopausal women is an extre-mely rare malignant tumor that was originally described as a unique group of soft tissue sarcomas originating from primitive mesenchymal *** was first re-ported in postmenopausal women in 1970,and fewer than 50 postmenopausal patients have been reported to *** SUMMARY A 68-year-old multiparous female was admitted to the hospital on October 11,2023,with the chief complaint of a mass causing vaginal prolapse with incomplete urination that had persisted for 4 *** vaginal mass was approximately the size of a pigeon egg;after lying down,the vaginal mass *** resection was performed,and vaginal pleomorphic RMS was diagnosed based on pathology and immunohistochemical staining *** patient is currently undergoing *** present study also reviewed the clinical,histolo-gical,and immunohistochemical features and latest treatment recommendations for vaginal *** abnormal vaginal mass should be promptly investigated through pelvic examination and appropriate *** current initial treat-ment for vaginal RMS is biopsy and primary *** When surgery is planned for vaginal RMS,an organ-preserving approach should be considered.

关键词： Rhabdomyosarcoma Vagina Postmenopausal woman Pleomorphic Case report