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Single-ended Time Domain Fault Location Based on Transient Signal Measurements of Transmission Lines

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Protection and Control of Modern Power Systems 2024年第2期9卷 61-74页

作者： Jian luo yao Liu Qiushi Cui Jiayong Zhong Lin Zhang Chongqing University ChongqingChina Taiyuan University of Technology TaiyuanChina School of Electrical Engineering and with the Liyang Smart City Research Institute Chongqing UniversityChongqing 400044China Electrical Engineering from chongqing University ChongqingChina State Grid Chongqing Electric Power Company Research Institute ChongqingChina

Precise fault location plays an important role in the reliability of modern power *** the in-creasing penetration of renewable energy sources,the power system experiences a decrease in system inertia and alterations in steady-state characteristics following a fault *** existing single-ended phasor domain methods assume a certain impedance of the remote-end system or consistent current phases at both *** problems present challenges to the applicability of con-ventional phasor-domain location *** paper presents a novel single-ended time domain fault location method for single-phase-to-ground faults,one which fully considers the distributed parameters of the line *** fitting of transient signals in the time domain is real-ized to extract the instantaneous amplitude and ***,to eliminate the error caused by assumptions of lumped series resistance in the Bergeron model,an im-proved numerical derivation is presented for the distrib-uted parameter line *** instantaneous symmet-rical components are extracted for decoupling and inverse transformation of three-phase recording *** on the above,the equation of instantaneous phase constraint is established to effectively identify the fault *** proposed location method reduces the negative effects of fault resistance and the uncertainty of remote end pa-rameters when relying on one-terminal data for ***,the proposed fault analysis methods have the ability to adapt to transient processes in power *** comparisons with existing methods in three different systems,the fault position is correctly identified within an error of 1%.Also,the results are not affected by sampling rates,data windows,fault inception angles,and load conditions. Index Terms—Fault location,distributed parameter line model,transient signal,renewable energy,instantaneous phase.

关键词： Fault location distributed parameter line model transient signal renewable energy instantaneous phase

Iterative Signal Detection Based Soft Interference Cancellation for Satellite-Terrestrial Downlink NOMA Systems

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China Communications 2024年第8期21卷 249-263页

作者： Sun meng Zhang Qi yao Haipeng Gao Ran Xin Xiangjun Tian Feng Feng Weiying Chen Dong School of Electronic Engineering Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China Beijing Key Laboratory of Space-Ground Interconnection and Convergence State Key Laboratory of Information Photonics and Optical CommunicationsSchool of Electronic EngineeringBeijing University of Posts and Telecommunications(BUPT)Beijing 100876China School of Information and Communication Engineering Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China Beijing Institute of Technology Beijing 100081China Beihang University Beijing 100191China China Academy of Space Technology(CAST) Beijing 100094China

To improve the bit error rate(BER)performance of multi-user signal detection in satelliteterrestrial downlink non-orthogonal multiple access(NOMA)systems,an iterative signal detection algorithm based on soft interference cancellation with optimal power allocation is *** that power allocation has a significant impact on BER performance,the optimal power allocation is obtained by minimizing the average BER of NOMA *** to the allocated powers,successive interference cancellation(SIC)between NOMA users is performed in descending power *** each user,an iterative soft interference cancellation is performed,and soft symbol probabilities are calculated for soft *** improve detection accuracy and without increasing the complexity,the aforementioned algorithm is optimized by adding minimum mean square error(MMSE)signal estimation before detection,and in each iteration soft symbol probabilities are utilized for soft-decision of the current user and also for the update of soft interference of the previous *** results illustrate that the optimized algorithm ***-IDBSIC significantly outperforms joint multi-user detection and SIC detection by 7.57dB and 8.03dB in terms of BER performance.

关键词： non-orthogonal multiple access(NOMA) resource allocation satellite-terrestrial communication signal detection soft interference cancellation

The Predictability Limit of Oceanic Mesoscale Eddy Tracks in the South China Sea

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Advances in Atmospheric Sciences 2024年第9期41卷 1661-1679页

作者： Hailong LIU Pingxiang CHU yao meng mengrong DING Pengfei LIN Ruiqiang DING Pengfei WANG Weipeng ZHENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laoshan Laboratory Qingdao 266237China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100872China Center for Monsoon System Research(CMSR) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China

Employing the nonlinear local Lyapunov exponent (NLLE) technique, this study assesses the quantitative predictability limit of oceanic mesoscale eddy (OME) tracks utilizing three eddy datasets for both annual and seasonal means. Our findings reveal a discernible predictability limit of approximately 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) within the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and large-radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also has seasonal variations, further finding that the area of higher predictability limits often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs characterized by high predictability limit values exhibit more extended and smoother trajectories and often move along the northern slope of the SCS.

关键词： predictability mesoscale eddy nonlinear local Lyapunov exponent South China Sea seasonal variability

Progression from ductal carcinoma in situ to invasive breast cancer:molecular features and clinical significance

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1841-1868页

作者： Jing Wang Baizhou Li meng luo Jia Huang Kun Zhang Shu Zheng Suzhan Zhang Jiaojiao Zhou The Key Laboratory of Cancer Prevention and Intervention China National Ministry of Educationthe Second Affiliated HospitalZhejiang University School of MedicineHangzhouChina Department of Breast Surgery and Oncology the Second Affiliated HospitalZhejiang University School of MedicineHangzhouChina Zhejiang Provincial Clinical Research Center for Cancer HangzhouChina Department of Pathology the Fourth Affiliated HospitalZhejiang University School of MedicineYiwuChina Department of Plastic Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhouChina Cancer Center Zhejiang UniversityHangzhouChina

Ductal carcinoma in situ(DCIS)represents pre-invasive breast *** untreated cases,25-60%DCIS progress to invasive ductal carcinoma(IDC).The challenge lies in distinguishing between non-progressive and progressive DCIS,often resulting in over-or under-treatment in many *** increasing screen-detected DCIS in these years,the nature of DCIS has aroused worldwide attention.A deeper understanding of the biological nature of DCIS and the molecular journey of the DCIS-IDC transition is crucial for more effective clinical ***,we reviewed the key signaling pathways in breast cancer that may contribute to DCIS initiation and *** also explored the molecular features of DCIS and IDC,shedding light on the progression of DCIS through both inherent changes within tumor cells and alterations in the tumor *** addition,valuable research tools utilized in studying DCIS including preclinical models and newer advanced technologies such as single-cell sequencing,spatial transcriptomics and artificial intelligence,have been systematically ***,we thoroughly discussed the clinical advancements in DCIS and IDC,including prognostic biomarkers and clinical managements,with the aim of facilitating more personalized treatment strategies in the *** on DCIS has already yielded significant insights into breast carcinogenesis and will continue to pave the way for practical clinical applications.

关键词： clinical breast alterations

GST family genes in jujube actively respond to phytoplasma infection

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Horticultural Plant Journal 2024年第1期10卷 77-90页

作者： Qipeng Wang Liman Zhang Chaoling Xue yao Zhang Xiangrui meng Zhiguo Liu mengjun Liu Jin Zhao College of Life Science Hebei Agricultural UniversityBaodingHebei 071000China Hebei Key Laboratory of Plant Physiology and Molecular Pathology Hebei Agricultural UniversityBaodingHebei 071000China Research Center of Chinese Jujube Hebei Agricultural UniversityBaodingHebei 071000China

Jujube witches’broom(JWB)caused by phytoplasma has a severely negative effect on multiple metabolisms in *** GST gene family in plants participates in the regulation of a variety of biotic and abiotic *** study aims to identify and reveal the changes in the jujube GST gene family in response to phytoplasma ***,70 ZjGSTs were identified in the jujube genome and divided into 8 *** them,the Tau-class,including 44 genes,was the *** analysis indicated that Tau-class genes were highly conserved among species,such as Arabidopsis,cotton,chickpea,and *** chromosome location analysis,37.1%of genes were clustered,and 8 of 9 gene clusters were composed of Tau class *** RT-PCR,qRT-PCR and enzyme activity detection,the results showed that the expression of half(20/40)of the tested ZjGSTs was inhibited by phytoplasma infection in field and tissue culture conditions,and GST activity was also significantly *** the resistant and susceptible varieties under phytoplasma infection,ZjGSTU49-ZjGSTU54 in the cluster IV showed opposite expression patterns,which may be due to functional divergence during *** upregulated genes(ZjGSTU45,ZjGSTU49,ZjGSTU59,and ZjGSTU70)might be involved in the process of jujube against *** yeast two-hybrid results showed that all 6 Tauclass proteins tested could form homodimers or ***,the comprehensive analysis of the jujube GST gene family revealed that ZjGSTs responded actively to phytoplasma ***,some screened genes(ZjGSTU24,ZjGSTU49-52,ZjGSTU70,and ZjDHAR10)will contribute to further functional studies of jujube-phytoplasma interactions.

关键词： Chinese jujube GST gene Family Phytoplasma Gene cluster Expression Protein interaction

Laparoscopic vs open surgery for gastric cancer: Assessing time, recovery, complications, and markers

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 40-48页

作者： Yun-yao Lu Yun-Xiao Li meng He Ya-Li Wang Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing 400030China

BACKGROUND Gastric cancer(GC)is one of the most common cancers *** and mortality have increased in recent years,making it an urgent issue to ***-paroscopic radical surgery(LRS)is a crucial method for treating patients with GC;However,its influence on tumor markers is still under *** data of 194 patients treated at Chongqing University Cancer Hospital bet-ween January 2018 and January 2019 were retrospectively *** who underwent traditional open surgery and LRS were assigned to the control(n=90)and observation groups(n=104),*** sample t-tests andχ2 tests were used to compare the two groups based on clinical efficacy,changes in tumor marker levels after treatment,clinical data,and the incidence of posto-perative *** investigate the association between tumor marker levels and clinical efficacy in patients with GC,three-year recurrence rates in the two groups were *** Patients in the observation group had a shorter duration of operation,less in-traoperative blood loss,an earlier postoperative eating time,and a shorter hospital stay than those in the control group(P0.05).After treatment,the overall response rate in the control group was significantly lower than that in the observation group(P=0.001).Furthermore,after treatment,the levels of carbohydrate antigen 19-9,cancer antigen 72-4,carcinoembryonic antigen,and cancer antigen 125 decreased *** observation group also exhibited a significantly lower incidence rate of postoperative complications compared to the control group(P0.05).CONCLUSION LRS effectively treats early gastric cancer by reducing intraoperative bleeding,length of hospital stays,and postoperative complications.I

关键词： Laparoscopic radical surgery Gastric cancer Serum tumor markers Prognosis Recurrence Intraoperative bleeding

Facile preparation of a SiC@SiO_(2)nanowire-toughened ZrB_(2)-SiC/SiC bilayer coating with good interfacial bonding,high toughness,and excellent cyclic ablation resistance on C/CA composites

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Journal of Advanced Ceramics 2024年第4期13卷 486-495页

作者： meng Yan Chenglong Hu Jian Li Shengyang Pang Bohui Sun Rida Zhao Bin Liang Rui luo Sufang Tang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Preparing antioxidant coatings to address the inherent oxidation sensitivity of carbon fiber-reinforced carbon aerogel(C/CA)composites is a feasible way to promote their application in oxidizing environments as thermal insulation ***,preparing the coatings with excellent oxidation and ablation resistance while avoiding evident damage to the C/CA substrate still remains a ***,a SiC@SiO_(2)nanowire-toughened ZrB2–SiC/SiC bilayer coating with a large thickness of 500μm was prepared on C/CA using a one-step low-temperature reaction sintering method,which simultaneously formed a sintered outer layer with even-distributed nanowires and a siliconized gradient inner *** courtesy of the synergic thermal response of the layers and the crack deflection induced by the nanowires,the resulting coating has moderate residual compressive stress of 0.08–1.22 GPa in the interface,high interfacial bonding strength of 6.02 MPa,and good fracture toughness of 4.36 MPa·m^(1/2).Benefited from the optimum components and improved structure,the coating shows excellent cyclic ablation resistance with linear ablation rates of 0.1μm/s at 1650℃for 1500 s(300 s×5 cycles)and 0.4μm/s at 1850℃for 900 s(300 s×3 cycles).The one-step preparation strategy contributes to little damage to the substrate,thus showing the well-preserved mechanical and thermal insulation properties.

关键词： coating carbon fiber reinforced carbon aerogel(C/CA)composites toughness interface residual stress

Illuminating spin-crossover octanuclear metal-organic cages

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Science China Chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova Yu-Xia Li Ke Sun meng Yu Zi-Shuo yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Institute of Physical and Organic Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical *** this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO *** them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity *** also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first *** calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

Bifunctional Silicon Quantum Dots for Antibacterial Application and Highly Sensitive Detection of Tetracycline

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Journal of Analysis and Testing 2024年第2期8卷 218-227页

作者： Shuiqin Chai Yuting Chi Wanlin Sun Xinyu Pei Shuchen Pei Chengyu Sun Kang luo Bo yao College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China People’s Hospital Affiliated to Chongqing Three Gorges Medical CollegeChongqing404037China

Silicon quantum dots(SiQDs)with high water-soluble and favorable photostability were prepared by a one-step hydrothermal *** average diameter of SiQDs was 2.02 nm characterized by transmission electron *** was to be noted that the as-prepared SiQDs showed eff ective antibacterial activity,which was attributed to electrostatic interaction and the generation of reactive oxygen *** minimum inhibitory concentration of SiQDs against Escherichia coli and Staphylococcus aureus was 0.45 mg/mL and 0.38 mg/mL,***,based on the static quenching eff ect-induced fluorescence quenching mechanism,the SiQDs exhibited high sensitivity and selectivity for detecting tetracyclines(TC).A good linear relationship was obtained between the fluorescence intensity of SiQDs and the concentration of tetracycline(TC)in the range of 0–0.08μmol/L(R^(2)=0.9993)with a detection limit of 0.0176μmol/***,the TC content in the honey samples was determined using the *** the results suggest that the as-prepared SiQDs can be a potential fluorescent probe for application in antibacterial and analysis.

关键词： Silicon quantum dots Antibacterial activity Reactive oxygen species Tetracycline detection