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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

Nitrogen availability mediates the effects of roots and mycorrhizal fungi on soil organic carbon decomposition:A meta-analysis

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Pedosphere 2024年第2期34卷 289-296页

作者： Tongshuo bai Yunpeng QIU Shuijin hu Ecosystem Ecology Laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh NC 27695USA

Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain *** on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion *** addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,***,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C ***,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root *** findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.

关键词： arbuscular mycorrhizal fungi ectomycorrhizal fungi leaf litter leguminous plant mycorhizosphere rhizosphere root litter soil C:N ratio

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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Efficient synthesis of forsterite via high-temperature thermochemical reactions from boron mud waste without briquetting

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Particuology 2024年第4期87卷 124-132页

作者： Fangling hu Liangliang Fu Qingjin Zhang Guangwen Xu Dingrong bai Key Laboratory on Resources Chermticals and Material of Ministry of Education Sheryang Unfversity of Chemical Technology.Shenyang110142China School of Chemical Engineering University of Science and Technology Liaoning.Anshan 114051China School of Materials Science and Engineering Shenyang University of Technology.Shenyang110142China

Forsterite is a highly demanded material in high-temperature industries due to its superior performance in elevated *** study proposes synthesizing high-quality forsterite via high-temperature thermochemical reactions using abundant boron mud *** new synthesis method capitalizes on the high reactivity of fine raw powder materials,enabling the reaction to reach completion at low temperatures *** chemical characteristics,microscopic morphology,and structure of synthe-sized samples are systematically studied using XRD and *** results confirm that boron mud can be efficiently transformed into forsterite after 10 min of reactions at 1500℃.The synthesized products attain over 98.7%densification and contain more than 85.0%forsterite with well-developed *** activation energy of forsterite grain growth in the 1100-1500℃temperature range is 165.5 kJ/*** study provides a low-cost method for producing forsterite and an efficient and environmentally friendly solution for treating solid waste.

关键词： Fluidized bed Boron mud Forsterite Solid state reaction Activation energy Grain growth

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

Mitigated lattice distortion and oxygen loss of Li-rich layered cathode materials through anion/cation regulation by Ti^(4+)-substitution

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Chinese Chemical Letters 2024年第2期35卷 548-552页

作者： Kaicheng Zhang Yu Tian Xuanjin Chen shan hu Zelang Jian State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China

Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen and trigger transition metal(TM)ions migrate to Li+vacancies,resulting in capacity *** we brought Ti4+in substitution of TM ions in Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),which could stabilize structure and expand the layer spacing of ***,optimized Ti-substitution can regulate the anions and cations of LLM,enhance the interaction with lattice oxygen,increase Ni^(3+) and Co^(3+),and improve Mn^(4+) coordination,improving reversibility of oxygen redox activation,maintaining the stable framework and facilitating the Li^(+) ***,we found 5%Ti-substitution sample delivered a high discharge capacity of 244.2 mAh/g at 50 mA/g,an improved cycling stability to 87.3%after 100 cycles and enhanced rate *** Ti-substitution gives a new pathway to achieve high reversible cycle retention for LLMs.

关键词： Lithium-rich layered cathode material Ti-substitution Anion/cation regulation Structural stability Cycling stability

Oleuropein alleviates sepsis-induced acute lung injury via the AMPK/Nrf-2/HO-1 signaling

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Asian Pacific Journal of Tropical Biomedicine 2024年第5期14卷 187-198页

作者： shan-hu Wang Yang-Yang Wu Xiao-Jiao Xia Department of Pediatrics The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang 325027China

Objective:To explore the effect of oleuropein on sepsis-induced acute lung injury(ALI)in vitro and in vivo and investigate the underlying ***:In an lipopolysaccharide(LPS)-mediated cell model of sepsis-induced ALI and a cecal ligation and puncture-induced mouse model of septic ALI,CCK-8 assay and flow cytometry analysis were used to detect cell activity and *** and relevant assay kits were used to measure the levels of inflammatory cytokines and oxidative stress,*** blot was applied to determine the expression of apoptosis-and AMP-activated protein kinase(AMPK)/nuclear factor erythroid 2-related factor-2(Nrf-2)/heme oxygenase-1(HO-1)signaling-associated ***-1 staining,adenosine triphosphate(ATP)assay kit,and MitoSOX Red assays were performed to detect mitochondrial membrane potential,ATP content,and mitochondrial ROS formation,***,lung injury was evaluated by measuring lung morphological alternations,lung wet-to-dry ratio,myeloperoxidase content,and total protein ***:Oleuropein reduced inflammatory reaction,oxidative damage,and apoptosis,and ameliorated mitochondrial dysfunction in LPS-exposed BEAS-2B cells and mice with septic ***,oleuropein activated the AMPK/Nrf-2/HO-1 signaling ***,these effects of oleuropein were abrogated by an AMPK inhibitor compound ***:Oleuropein can protect against sepsis-induced ALI in vitro and in vivo by activating the AMPK/Nrf-2/HO-1 signaling,which might be a potential therapeutic agent for the treatment of sepsis-induced ALI.

关键词： AMPK/Nrf-2/HO-1 signaling Inflammatory response Lung damage Mitochondrial dysfunction Oleuropein Oxidative stress Sepsis

Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography

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Defence Technology（防务技术） 2024年第7期37卷 162-172页

作者： Pengyu hu Jiangpeng Wu Zhengang Yan Meng He Chao Liang Hao bai Xi'an Modern Control Technology Research Institute Xi'an710065China Xi'an OET Science and Technology Co. LtdXi'an710076China

High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high ***,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment *** address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo ***,background difference algorithm is utilized to extract the center and area of each fragment in the image ***,a multi-object tracking(MOT)algorithm using Kalman filtering and hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment *** reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial ***,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10~3fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.

关键词： Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction

Construction of novel P-Si/TiO_(2)/HfO_(2)/MoS_(2)/Pt heterophotocathode for enhanced photoelectrochemical water splitting

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Nano Research 2024年第5期17卷 4428-4436页

作者： Jiaru Li Jiayu bai Songjie hu Wenyu Yuan Yuyu Bu Xiaohui Guo Key Lab of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Shaanxi Key Laboratory for Carbon Neutral TechnologyThe College of Chemistry and Materials ScienceNorthwest UniversityXi'an 710069China Key Lab of Wide Band-Gap Semiconductor Materials and Devices School of MicroelectronicsXidian UniversityXi’an 710071China Key Lab of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationSchool of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an 710062China

Photoelectrochemical devices have been developed to enable the conversion of solar ***,their commercial potential is restricted by the limited stability of the materials *** enhance the stability of photocathode and its solar water splitting performance,a P-Si/TiO_(2)/HfO_(2)/MoS_(2)/Pt composite photocathode is developed in this *** novel TiO_(2)/HfO_(2)/MoS_(2) serial nanostructure provides excellent stability of the photocathode,and optimizes the interface energy barrier to further facilitate the transfer process of photogenerated carriers within the *** best P-Si/TiO_(2)/HfO_(2)/MoS_(2)/Pt photocathode demonstrates an initial potential of 0.5 V(***)and a photocurrent density of-29 mA/cm^(2) at 0 V(***).Through intensity modulated photocurrent spectroscopy and photoluminescence test,it is known that the enhanced water splitting performance is attributed to the optimized carrier transfer *** findings provide a feasible strategy for the stability and photon quantum efficiency enhancement of silicon-based photocathode devices.

关键词： photoelectrochemical water splitting stability surface/interface engineering HfO_(2)layer