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A C_(6)-decomposition of theλ-fold Line Graph of K_(x,y)
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作者 XIN Yue YANG Weihua 《数学进展》 北大核心 2025年第6期1205-1222,共18页
In this paper,we prove that L(K_(x,y))(λ),theλ-fold line graph of the complete bipartite graph Ka,y,has a C_(6)-decomposition if and only if ry≥6,λxy(c+y-2)=0(mod 12)and(x+y)=0(mod 2),where x,y are nonnegative int... In this paper,we prove that L(K_(x,y))(λ),theλ-fold line graph of the complete bipartite graph Ka,y,has a C_(6)-decomposition if and only if ry≥6,λxy(c+y-2)=0(mod 12)and(x+y)=0(mod 2),where x,y are nonnegative integers and(x,y)≠(2,4)or(2,5). 展开更多
关键词 cycle decomposition line graph complete bipartite graph
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A Study of Multiple Molecular Lines at the 3 mm Band toward Gas Infalling Sources
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作者 Yang Yang Xi Chen +3 位作者 Zhibo Jiang Zhiwei Chen Shuling Yu Jun Li 《Research in Astronomy and Astrophysics》 2025年第5期230-245,共16页
The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within ... The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within the 3 mm band using the FTS wide-sideband mode of the IRAM 30 m telescope toward 20 gas-infalling sources.Using XCLASS,we identify the emission lines of up to 22 molecular species(including a few isotopologues)and on hydrogen radio recombination line in these sources.H^(13)CO^(+),HCO^(+),HCN,HNC,c-C_(3)H_(2),and CCH lines are detected in 15 sources.We estimate the rotation temperatures and column densities of these molecular species using the LTE radiative transfer model,and compare the molecular abundances of these sources with those from nine high mass star-forming regions reported in previous studies and with those from the chemical model.Our results sugges that G012.79-0.20,G012.87-0.22 clump A and B,and G012.96-0.23 clump A may be in the high-mass protostella object stage,while sources with fewer detected species may be in the earlier evolutionary stage.Additionally,th CCH and c-C_(3)H_(2)column densities in our sources reveal a linear correlation,with a ratio of N(CCH)/N(c-C_(3)H_(2)=89.2±5.6),which is higher than the ratios reported in the literature.When considering only sources with lowe column densities,this ratio decreases to 29.0±6.1,consistent with those of diffuse clouds.Furthermore,comparison between the N(CCH)/N(c-C_(3)H_(2))ratio and the sources’physical parameters reveals a correlation,with sources exhibiting higher ratios tending to have higher kinetic temperatures and H2column densities. 展开更多
关键词 GALAXIES star formation-ISM clouds-ISM lines and bands-ISM MOLECULES
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Numerical Simulation and Diagnostic Analysis for the Maintenance Mechanism of the “3·31” Squall Line Event in Jiangxi Province
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作者 XU Yuan WU Jing +2 位作者 DONG Meng ZHAO Xin-yu TIAN Gao-shan 《Journal of Tropical Meteorology》 2025年第6期622-636,共15页
The “3·31” severe squall line event in eastern China was notable for its exceptional intensity and persistence,posing significant challenges to forecast accuracy. This study analyzed the maintenance stage of th... The “3·31” severe squall line event in eastern China was notable for its exceptional intensity and persistence,posing significant challenges to forecast accuracy. This study analyzed the maintenance stage of this event using highresolution convection-permitting numerical simulations, with a focus on vorticity budgets of the environmental flow, multiscale synoptic diagnostics, and Rotunno-Klemp-Weisman(RKW) theory. These analyses aimed to elucidate the mechanisms governing the morphological transition, the generation of associated convective gales, and the prolonged maintenance of the squall line event. The results show that the numerical simulation accurately reproduced the development and evolution of the squall line, particularly its location, with surface wind errors remaining within a reasonable range. The development of a mesoscale vortex modulated the dynamic and water vapor fields, providing favorable mesoscale environmental conditions for the organization and maintenance of the squall line. Vorticity budget analysis indicates that the divergence and tilting terms were the primary contributors to vorticity tendency. After the squall line entered Jiangxi Province, it exhibited a sharper leading edge and enhanced upward motion. Dry intrusion from the mid-toupper troposphere led to rapid downward momentum transfer at the meso-γ scale, thereby generating convective gales. In addition, the enhancement of the rear-inflow jet(RIJ) was related to the pressure difference between the interior and exterior of system, which resulted from the phase change of condensate within tilted updrafts. The RIJ was orthogonal to the squall line, causing it to transform from a linear into a bowing shape. Diagnosis based on the RKW theory underscore the important roles in both low-level and deep vertical wind shear in maintenaning the squall line. The ratios of the cold pool propagation velocity to the vertical wind shear were close to 1, which balanced with the ambient horizontal vorticity that allowed the convection to remain upright, thus sustaining the squall line's intensity for an extended period. In summary, the squall line event was sustained by a favorable environment created by the environmental vortex. The dry intrusion from the mid-to-upper troposphere and intensified RIJ resulted in the severe convective winds, while the balance between cold pool and ambient vertical wind shear promoted the system's prolonged maintenance. These findings provide an effective reference for the short-range forecasting of squall lines throughout their lifecycle. 展开更多
关键词 squall line bow echo convective gales numerical simulation maintenance mechanism
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Development of Gossypium hirsutum–Gossypium raimondii introgression lines and their use in QTL mapping of agricultural traits
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作者 Liang Wang Nijiang Ai +12 位作者 Zechang Zhang Chenhui Zhou Guoli Feng Sheng Cai Ningshan Wang Liuchun Feng Yu Chen Min Xu Yingying Wang Haoran Yue Mengfei Chen Liangshuai Xing Baoliang Zhou 《Journal of Integrative Agriculture》 2025年第5期1688-1703,共16页
Gossypium raimondii(2n=2x=26,D_(5)),an untapped wild species,is the putative progenitor of the D-subgenome of G.hirsutum(2n=4x=52,AD_(1)),an extensively cultivated species.Here,we developed a G.hirsutum(recipient)–G.... Gossypium raimondii(2n=2x=26,D_(5)),an untapped wild species,is the putative progenitor of the D-subgenome of G.hirsutum(2n=4x=52,AD_(1)),an extensively cultivated species.Here,we developed a G.hirsutum(recipient)–G.raimondii(donor)introgression population to exploit the favorable QTLs/genes and mapped potential quantitative trait loci(QTLs)from wild cotton species.The introgression population consisted of 256 lines with an introgression rate of 52.33%for the G.raimondii genome.The introgression segment length range was 0.03–19.12 Mb,with an average of 1.22 Mb.The coverage of total introgression fragments from G.raimondii was 386.98 Mb.Further genome-wide association analysis(Q+K+MLM)and QTL mapping(RSTEP-LRT)identified 59 common QTLs,including 14 stable QTLs and six common QTL(co-QTL)clusters,and one hotspot of micronaire(MIC).The common QTLs for seed index all showed positive additive effects,while the common QTLs for boll weight all had negative additive effects,indicating that the linkage between seed index and boll weight could be broken.QTLs for lint percentage showed positive effects and could be beneficial for improving cotton yield.Most QTLs for fiber quality had negative additive effects,implying these QTLs were domesticated/improved in G.hirsutum.A few fiber quality QTLs showed positive additive effects,so they could be used to improve cotton fiber quality.The introgression lines developed could be useful for molecular marker-assisted breeding and mapping QTLs precisely for mining desirable genes from the wild species G.raimondii.Such genes can improve cultivated cotton in the future through a designbreeding approach. 展开更多
关键词 Gossypium hirsutum Gossypium raimondii introgression lines YIELD fiber quality quantitative trait locus
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Introgressed eggplant lines with the wild Solanum incanum evaluated under drought stress conditions
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作者 Martín Flores-Saavedra Pietro Gramazio +5 位作者 Santiago Vilanova Diana M.Mircea Mario X.Ruiz-González Óscar Vicente Jaime Prohens Mariola Plazas 《Journal of Integrative Agriculture》 2025年第6期2203-2216,共14页
As access to irrigation water becomes increasingly limited, introgression of relevant genomic regions from drought-tolerant wild genotypes is a promising breeding strategy for crop plants. In this study, nine eggplant... As access to irrigation water becomes increasingly limited, introgression of relevant genomic regions from drought-tolerant wild genotypes is a promising breeding strategy for crop plants. In this study, nine eggplant(Solanum melongena) introgression lines(ILs) covering altogether 71.6% of the genome of the donor wildrelative parent S. incanum were evaluated for drought tolerance under water stress conditions. Plants at the five true leaves stage were irrigated at either 100%(control) or 30%(water stress) field capacity for 14 days, and growth and biochemical traits were measured. Reduced irrigation resulted in decreased growth and increased stress markers such as proline and malondialdehyde. Most ILs had lower growth and biomass production thanthe cultivated parent under both conditions. However, the wild alleles for two genomic regions related to stem and root dry weight conferred improved tolerance to water stress. In addition, several S. incanum alleles had a positive effect on important traits that may improve yield under drought conditions, such as leaf water content water use efficiency, and chlorophyll content. Fine-mapping the genomic regions for tolerance and reducinglinkage drag with regions affecting growth will be crucial for significantly improving eggplant drought tolerance through introgression breeding. 展开更多
关键词 Solanum melongena S.incanum introgression lines water stress oxidative stress genomic regions
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A Novel Functional Method of Protector Screening for Zebrafish Lateral Line Hair Cells via the Acoustic Escape Response
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作者 Ling Zheng Qiaosen Shen +8 位作者 Tong Zhao Qingsong Liu Zihao Huang Feng Zhao Mengqian Zhang Yongdong Song Daogong Zhang Dong Liu Fangyi Chen 《Neuroscience Bulletin》 2025年第9期1537-1552,共16页
Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate ... Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate pool of HC protectors,a self-built acoustic escape response(AER)-detecting system was developed to apply both low-frequency near-field sound transmission and AER image acquisition/processing modules.The device quickly confirmed the changed LL HC functions caused by most known ototoxins,protectors,and neural transmission modifiers,or knockdown of LL HC-expressing genes.With ten devices wired in tandem,five‘hit’chemicals were identified from 124 cyclin-dependent kinase inhibitors to partially restore cisplatin-damaged AER in less than a day.AS2863619,ribociclib,and SU9516 among the hits,protected the HCs in the mouse cochlea.Therefore,using free-swimming larval zebrafish,the self-made AER-detecting device can efficiently identify compounds that are protective against HC damage,including cell death and loss-of-function. 展开更多
关键词 Acoustic escape response Zebrafish Lateral line Hair cell Low-frequency sound Functional screening
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Research on the Optimization and Simulation of Assembly Line Balancing Based on Improved PSO Algorithm
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作者 Wenkang Zhang 《Journal of World Architecture》 2025年第3期159-168,共10页
In response to the deficiencies of commonly used optimization methods for assembly lines,a production demand-oriented optimization method for assembly lines is proposed.Taking a certain compressor assembly line as an ... In response to the deficiencies of commonly used optimization methods for assembly lines,a production demand-oriented optimization method for assembly lines is proposed.Taking a certain compressor assembly line as an example,the production rhythm and the number of workstations are calculated based on production requirements and working systems.With assembly rhythm and smoothing index as optimization goals,an improved particle swarm optimization algorithm is employed for process allocation.Subsequently,Flexsim simulation is used to analyze the assembly line.The final results show that after optimization using the improved particle swarm algorithm,the assembly line balance rate increased from 71.1%to 85.9%,and the assembly line smoothing index decreased from 47.4 to 29.8,significantly enhancing assembly efficiency.This demonstrates the effectiveness of the proposed optimization method for the assembly line and provides a reference for other products in the same industry. 展开更多
关键词 Assembly line balance Improve PSO Simulation optimization
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Impact of Single-Phase Automatic Recloser of Critical Transmission Line on the Stability of the Power Transmission Network
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作者 Chuulan Natsagdorj Ganbat Gantamir Erdenebileg Doljinsuren 《Journal of Power and Energy Engineering》 2025年第2期43-56,共14页
In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220... In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults. 展开更多
关键词 Automatic Reclosing Single-Phase Automatic Reclosing Relay Protection Overhead Power lines System Stability Rotor Angle Stability
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Conduction and Coupling Test of Lightning Current Invading the N-line of Box-type Transformer
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作者 Yinghui HUANG Xiaoqing PAN +3 位作者 Renhong GUO Zengru YANG Jianbo LUO Zhongqiu SHI 《Meteorological and Environmental Research》 2025年第6期59-64,共6页
In theory,due to the fact that the grounding wire PE of wind turbine and the N-line(directly grounded)of the Y-shaped wiring on the low-voltage side of the box-type transformer share the grounding body,when the wind t... In theory,due to the fact that the grounding wire PE of wind turbine and the N-line(directly grounded)of the Y-shaped wiring on the low-voltage side of the box-type transformer share the grounding body,when the wind turbine is struck by lightning,the lightning current is directly conducted to the N-line on the low-voltage side of the box-type transformer(invasion mode of transformer synonym end).At the same time,conducted overvoltage pulse is generated in the three-phase winding on the low-voltage side,and coupled to the high-voltage side of the box-type transformer(Δconnection)to generate coupling overvoltage pulse.After investigation,the existing regulations on the tripping rate of power lines have not taken into account the impact of wind turbines being struck by lightning on line tripping,and the mechanism is still unclear.In order to further analyze the causes of lightning tripping of collection line circuit breakers in wind farms,it is necessary to study the physical process of how lightning current is conducted(coupled)to the collection line through the box-type transformer after lightning strikes on the wind turbines.In this paper,the test method of"conduction and coupling test of lightning current invading transformer N-line",and the waveform parameters(polarity,phase,amplitude,and transformation ratio)of the primary and secondary windings of the box-type transformer when lightning current invades the transformer N-line are introduced.It can provide assistance for operation and maintenance personnel to analyze the reasons for lightning tripping of 35 kV line circuit breakers in wind farms. 展开更多
关键词 Wind farm Box-type transformer Lightning current invading N line Conduction and coupling test
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SpeedBot:Top-notch Product to Empower the Upgrading of Smart Factory and Production Line
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作者 Zhang Li 《China's Foreign Trade》 2025年第3期32-37,共6页
China International Supply Chain Expo(hereinafter referred to as the CISCE)is a key platform for enterprises to showcase their innovation strength and connect with global resources.As a“hidden champion”in the field ... China International Supply Chain Expo(hereinafter referred to as the CISCE)is a key platform for enterprises to showcase their innovation strength and connect with global resources.As a“hidden champion”in the field of intelligent manufacturing,Hunan SpeedBot Robot ics Co.,Ltd.(hereinaf ter refer red to as“SpeedBot”)is planning to display its independently developed“AI+3D Vision”core technology at the CISCE,to empower the supply chain of industries such as automobiles and heavy industry through a full-process automated detection solution.Liu Tingting,Vice General Manager of SpeedBot,said in an interview with China’s Foreign Trade,“The CISCE is not only a window for technology display,but also a link to promote collaborative innovations of the whole industrial chain.We look forward to building resilient supply chains with global partners and bringing China’s‘smart’manufacturing to the world.” 展开更多
关键词 supply chain production line intelligent manufacturinghunan connect global resourcesas empower supply chain showcase their innovation strength AI heavy industry
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NONLINEAR WAVE TRANSITIONS AND THEIR MECHANISMS OF THE(2+1)-DIMENSIONAL KORTEWEG-DE VRIES-SAWADA-KOTERA-RAMANI EQUATION
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作者 Haolin WANG Shoufu TIAN Tiantian ZHANG 《Acta Mathematica Scientia》 2025年第4期1405-1437,共33页
In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the... In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the N-soliton solution into complex numbers,the breath wave solution is constructed.The lump wave solution is derived through the long wave limit method.Then,by choosing appropriate parameter values,we acquire a number of transformed nonlinear waves whose gradient relation is discussed according to the ratio of the wave parameters.Furthermore,we reveal transition mechanisms of the waves by exploring the nonlinear superposition of the solitary and periodic wave components.Subsequently,locality,oscillation properties and evolutionary phenomenon of the transformed waves are presented.And we also prove the change in the geometrical properties of the characteristic lines leads to the phenomena of wave evolution.Finally,for higher-order waves,a range of interaction models are depicted along with their evolutionary phenomena.And we demonstrate that their diversity is due to the fact that the solitary and periodic wave components produce different phase shifts caused by time evolution and collisions. 展开更多
关键词 the(2+1)-dimensional Korteweg-de Vries-Sawada-Kotera-Ramani equation characteristic line transformed nonlinear waves phase shift collision
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Overall survival with frontline vs subsequent anti-epidermal growth factor receptor therapies in unresectable,RAS/BRAF wild-type,leftsided metastatic colorectal cancer
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作者 Nussara Pakvisal Richard M Goldberg +5 位作者 Chirawadee Sathitruangsak Witthaya Silaphong Satawat Faengmon Nattaya Teeyapun Chinachote Teerapakpinyo Suebpong Tanasanvimon 《World Journal of Clinical Oncology》 2025年第3期57-67,共11页
BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metasta... BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metastatic colorectal cancer(mCRC).Several studies have also demonstrated the benefit of anti-EGFR therapy in sub-sequent line settings for this patient population.However,direct evidence com-paring the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited,leaving a crucial gap in guiding optimal treatment strategies.AIM To compare overall survival(OS)between frontline and subsequent anti-EGFR treatment in patients with unresectable,RAS and BRAF wild-type,left-sided mCRC.METHODS We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital,Thailand,between January 2013 and April 2023.Patients were classified into two groups based on the sequence of their anti-EGFR treatment.The primary endpoint was OS.RESULTS Among 222 patients with a median follow-up of 29 months,no significant difference in OS was observed between the frontline and subsequent-line groups(HR 1.03,95%CI:0.73-1.46,P=0.878).The median OS was 35.53 months(95%CI:26.59-44.47)for the frontline group and 31.60 months(95%CI:27.83-35.37)for the subsequent-line group.In the subsequent-line group,71 patients(32.4%)who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months(95%CI:12.87-26.53).CONCLUSION Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable,RAS/BRAF wild-type,left-sided mCRC patients,but early exposure is vital for those unlikely to receive subsequent therapy. 展开更多
关键词 Metastatic colorectal cancer Anti-epidermal growth factor receptor FRONTline Subsequent line RAS wild-type metastatic colorectal cancer BRAF wild-type metastatic colorectal cancer Left-sided metastatic colorectal cancer Overall survival
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Sharp Bounds for ABS Index of Line,Total and Mycielski Graphs
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作者 YE Qingfang LI Fengwei 《数学进展》 北大核心 2026年第1期45-59,共15页
The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isome... The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isomers,such as boiling point,of formation are found to be better measured by the ABS index than by the Randi,atom-bond connectivity(ABC),and sum-connectivity(SC)indices.One important source of information for researching the molecular structure is the bounds for its topological indices.The extrema of the ABS index of the line,total,and Mycielski graphs are calculated in this work.Moreover,the pertinent extremal graphs were illustrated. 展开更多
关键词 ABS index line graph total graph Mycielski graph
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Probing the Warm and Hot Absorbers along the Sightline of PG 0052+251
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作者 Zheng Zhou Junjie Mao +5 位作者 Taotao Fang Yijun Wang Jiayi Chen Fabrizio Nicastro Kaile Wang Yi Zhang 《Research in Astronomy and Astrophysics》 2025年第7期102-110,共9页
We analyze the absorption features in the public 73 ks XMM-Newton spectra of the Seyfert 1 galaxy PG 0052+251.Our analysis reveals the presence of a warm absorber(WA)intrinsic to the source and the hot circumgalactic ... We analyze the absorption features in the public 73 ks XMM-Newton spectra of the Seyfert 1 galaxy PG 0052+251.Our analysis reveals the presence of a warm absorber(WA)intrinsic to the source and the hot circumgalactic medium at zero redshift.The identified WA is inflowing toward the central black hole,with a velocity shift of■.The ionization parameter of the WA is■,showing strong O II and O III absorption lines,along with a significant absorption of the spectral continuum at?10?.The line of sight toward PG 0052+251 intersects the halo of M31 at an impact parameter of approximately 218 kpc.Several local(z~0)absorption lines,like O VII,O VIII,and Ne IX,were detected.The derived hydrogen column density of the local hot gas is 2.2–2.6σhigher than those estimated by several models of the Galactic hot halo,suggesting a likely contribution from the M31 halo.We also find two absorption features at24.305?and 21.410?,which are unlikely to be associated with the hot halos or the warm-hot intergalactic medium but imply the presence of an additional WA component with an outflow velocity of approximately-7000 km s^(-1). 展开更多
关键词 (galaxies:)quasars:individual(PG 0052+251) (galaxies:)quasars:absorption lines galaxies:halos galaxies:individual(M31) X-rays:galaxies
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Two-dimensional grating line parameter calibration based on biaxial phase mapping
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作者 TENG Hai-rui LIANG Xu +3 位作者 JIN Si-yu SUN Yu-jia LI Wen-hao LIU Zhao-wu 《中国光学(中英文)》 北大核心 2026年第2期407-420,共14页
The two-dimensional grating serves as a critical component in plane grating interferometers for achieving high-precision multidimensional displacement measurements.The calibration of grating groove density and orthogo... The two-dimensional grating serves as a critical component in plane grating interferometers for achieving high-precision multidimensional displacement measurements.The calibration of grating groove density and orthogonality error of grating grooves not only improves the positioning accuracy of grating interferometers but also provides essential feedback for optimizing two-dimensional grating fabrication.This study proposes a method for simultaneous calibration of these parameters using orthogonal heterodyne laser interferometry.A two-dimensional grating interferometer is built with the grating to be measured,and a biaxial laser interferometer provides a displacement reference for it.The phase mapping relationship between grating interference and laser interference is established.The interference phase information obtained by any two displacements can simultaneously solve the above three parameters and obtain the grating installation error.The feasibility of the proposed method is verified by using a 1200 gr/mm two-dimensional grating.The standard deviation of the grating groove density in the X and Y directions is 0.012 gr/mm and 0.014 gr/mm,respectively.The standard deviation of the orthogonality error of grating grooves is 0.004°,and the standard deviation of the installation error is 0.002°.Compared with the atomic force microscope method,the consistency of the grating groove density in the X and Y directions is better than 0.03 gr/mm and 0.06 gr/mm,and the orthogonality error of grating grooves is better than 0.008°.The experimental results show that the proposed method can be simply and efficiently applied to the calibration of the grating line parameters of the two-dimensional grating. 展开更多
关键词 two-dimensional grating grating line parameter calibration grating groove density orthogonality error of grating grooves
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"Three Lines One Permit"environmental policy and its implementation assessment:a case study of Sichuan Province,China
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作者 LIU Yanguo WANG Li +5 位作者 YANG Ye LI Jingji PEI Xiangjun WANG Ziqin HE Yu CHEN An 《Journal of Mountain Science》 2026年第1期311-326,共16页
Integrated environmental management is important for sustainable development.Under China’s“Three Lines One Permit”(TLOP)policy,three types of management zones—priority protection,critical control,and general contr... Integrated environmental management is important for sustainable development.Under China’s“Three Lines One Permit”(TLOP)policy,three types of management zones—priority protection,critical control,and general control zones—are established based on the ecological red line,the lower-limit line for environmental quality,and the resource use line.Human activities are regulated through a permit system.Integrated and multifactorial protection of soil,plant,hydrological,and atmospheric elements is promoted at the regional level.A follow-up assessment contributes to the improvement of policy implementation and effectiveness.This study demonstrates the achievements of the TLOP policy in Sichuan Province.Results show that(1)276 protection zones have been established under the ecological red line,covering key ecosystems and protected areas to ensure environmental security.Under the lower-limit line,1,626 functional(priority,key,and general control)zones have been designated to regulate air,water,and soil quality,enhancing environmental capacity and pollution control.(2)Through the integration and merging of the three lines,1,128 integrated management zones have been established,including 375,625,and 128 priority protection,critical control,and general control zones,respectively.Each zone has its own list of environmental permits to regulate human activities according to different environmental protection and natural resource development regimes.(3)The design of the follow-up assessment index system was informed by regional primary functions and industrial structure.The index system for provinces and cities is structured around three primary indicators—implementation updating,application,and guarantees—and 15 secondary indicators.The system for critical control zones is structured around environmental access,management,and effectiveness and 14 secondary indicators.A stringent environmental zoning system has been established through the TLOP policy,thereby safeguarding environmental security,promoting harmonious existence between humans and nature,and supporting the vision of Beautiful China. 展开更多
关键词 Three lines One Permit Environment zoning system Ecological red line Environment assessment Southwest China
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Improvement of Traveling Wave-based Fault Location Method for Overhead Distribution Lines
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作者 Xinyi Zhang Bingyin Xu +1 位作者 Zhaoru Han Fang Shi 《Protection and Control of Modern Power Systems》 2026年第1期157-172,共16页
Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(M... Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(MV)distribution lines.However,current practices in its deployment,signal measurement,and threshold setting are usually from the application experiences in transmission lines,despite significant differences in fault-induced wave characteristics between transmission and distribution systems.To address these issues,this paper investigates the feasibility and applicability of TW fault technology in MV overhead distribution lines through characteristic analysis of fault-induced TWs.The propagation characteristics of aerial mode and zero mode TWs on overhead distribution lines are studied.Furthermore,it evaluates the influence of critical distri-bution network components including distribution transformers,multi-branch configurations,and busbar structures on wave propagation characteristics.Deployment strategies for traveling wave fault location(TWFL)devices is proposed to address the unique challenges of distribution networks,while the fault location method is also improved.Field test results demonstrate the effectiveness of the proposed methodology,showing improved fault detection accuracy and system reliability in distri-bution network applications.This research provides practical implementation suggestions for TWFL technology in distribution networks. 展开更多
关键词 Branch lines distribution network overhead lines propagation characteristics traveling wave based fault location
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Lane Line Detection Method for Complex Road Scenes Based on DeepLabv3+and MobilenetV4
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作者 Yingkai Ge Jiasheng Zhang +3 位作者 Jiale Zhang Zhenguo Ma Yu Liu Lihua Wang 《Computers, Materials & Continua》 2026年第4期1341-1363,共23页
With the continuous development of artificial intelligence and computer vision technology,numerous deep learning-based lane line detection methods have emerged.DeepLabv3+,as a classic semantic segmentation model,has f... With the continuous development of artificial intelligence and computer vision technology,numerous deep learning-based lane line detection methods have emerged.DeepLabv3+,as a classic semantic segmentation model,has found widespread application in the field of lane line detection.However,the accuracy of lane line segmentation is often compromised by factors such as changes in lighting conditions,occlusions,and wear and tear on the lane lines.Additionally,DeepLabv3+suffers from high memory consumption and challenges in deployment on embedded platforms.To address these issues,this paper proposes a lane line detection method for complex road scenes based on DeepLabv3+and MobileNetV4(MNv4).First,the lightweight MNv4 is adopted as the backbone network,and the standard convolutions in ASPP are replaced with depthwise separable convolutions.Second,a polarization attention mechanism is introduced after the ASPP module to enhance the model’s generalization capability.Finally,the Simple Linear Iterative Clustering(SLIC)superpixel segmentation algorithmis employed to preserve lane line edge information.MNv4-DeepLabv3+was tested on the TuSimple and CULane datasets.On the TuSimple dataset,theMean Intersection over Union(MIoU)and Mean Pixel Accuracy(mPA)improved by 1.01%and 7.49%,respectively.On the CULane dataset,MIoU andmPA increased by 3.33%and 7.74%,respectively.Thenumber of parameters decreased from 54.84 to 3.19 M.Experimental results demonstrate that MNv4-DeepLabv3+significantly optimizes model parameter count and enhances segmentation accuracy. 展开更多
关键词 Deep learning lane line detection DeepLabv3+ MobileNetV4 SLIC
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Review of Deep Learning-Based Intelligent Inspection Research for Transmission Lines
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作者 Jingjing Liu Chuanyang Liu 《Computers, Materials & Continua》 2026年第5期155-198,共44页
Intelligent inspection of transmission lines enables efficient automated fault detection by integrating artificial intelligence,robotics,and other related technologies.It plays a key role in ensuring power grid safety... Intelligent inspection of transmission lines enables efficient automated fault detection by integrating artificial intelligence,robotics,and other related technologies.It plays a key role in ensuring power grid safety,reducing operation and maintenance costs,driving the digital transformation of the power industry,and facilitating the achievement of the dual-carbon goals.This review focuses on vision-based power line inspection,with deep learning as the core perspective to systematically analyze the latest research advancements in this field.Firstly,at the technical foundation level,it elaborates on deep learning algorithms for intelligent transmission line inspection based on image perception,covering object detection algorithms,semantic segmentation algorithms,and other relevant methodologies.Secondly,in application practice,it summarizes deep learning-based intelligent inspection applications across six dimensions—including detection of power insulators and their defects,transmission tower detection,power line feature extraction,metal fitting and defect detection,thermal fault diagnosis of power components,and safety hazard detection in power scenarios,and further lists relevant public datasets.Finally,in response to current challenges,it identifies five key future research directions,such as the deep integration of multiple learning paradigms,multi-modal data fusion,collaborative application of large and small models,cloud-edge-end collaborative integration,and multi-agent cluster control.This paper reviews and analyzes numerous deep learning-based intelligent detectionmethods for aerial images,comprehensively explores the application of deep learning in Unmanned Aerial Vehicle(UAV)inspection scenarios,and thus provides valuable theoretical and practical references for scholars engaged in smart grid automated inspection research. 展开更多
关键词 Intelligent inspection transmission lines deep learning defect detection
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Development and application of a real-time baseband spectral line digital backend
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作者 Qingsong Zhang Maozheng Chen Jian Li 《Astronomical Techniques and Instruments》 2026年第2期170-183,共14页
Owing to its large aperture and advanced receivers,research plans for the Qitai 110 m radio telescope(QTT)include a variety of spectral line scientific studies.Sequential construction of receiver systems and multidisc... Owing to its large aperture and advanced receivers,research plans for the Qitai 110 m radio telescope(QTT)include a variety of spectral line scientific studies.Sequential construction of receiver systems and multidisciplinary planning require overcoming serious challenges to spectral line digital backend development,notably to digitize,process,and transmit considerable quantities of observational data,to minimize time-to-science with an easily scalable architecture,and to provide robust,high-quality data.As a proof-of-concept for the QTT backend,here we implement a baseband spectral line digital backend with a SNAP+GPU architecture.The SNAP-based digital frontend comprises two digitization links(1000 MHz,8-bit),two parallel quad-channel preprocessing modules,a quantization module,and a finite-state packaging module,generating a 100-MHz bandwidth digital link from the original analog signal through high-speed Ethernet transmission.The GPU node receives preprocessed baseband packets,constructs a ring buffer for lossless unpacking and distributing,with real-time data reception and caching,and conducts real-time spectral analysis(frequency resolution:3.051 kHz)of the 100 MHz baseband data.We evaluated system performance experimentally using spectral line observations with the Nanshan 26-m radio telescope(NSRT).For the QTT,the SNAP digital frontend will be seamlessly migrated to a radio frequency system-on-chip(RFSoC)architecture,resulting in five-and tenfold increases in instantaneous bandwidth and data throughput,respectively.The low-coupling digital frontend and GPU node can be easily extended to multiple nodes. 展开更多
关键词 QTT Spectral lines backend BASEBAND SNAP+GPU
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