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Emphasizing Theoretical Innovation in the Renovation ofExisting Urban Rail Transit Lines
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作者 DING Shukui 《城市轨道交通研究》 北大核心 2026年第1期167-168,共2页
Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines ... Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field. 展开更多
关键词 urban rail transit industry development trends existing lines renovation existing lines urban rail transit hereinafter RENOVATION urbanrail transit lines theoretical innovation
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A case of linear and whorled nevoid hypermelanosis
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作者 Jinxu Qi Yijia He Guoqiang Zhang 《Journal of Biomedical Research》 2026年第1期97-98,共2页
Dear Editor,Linear and whorled nevoid hypermelanosis(LWNH)is a rare,sporadic pigmentary disorder characterized by hyperpigmented macules arranged in linear streaks and whorls along Blaschko's lines,typically appea... Dear Editor,Linear and whorled nevoid hypermelanosis(LWNH)is a rare,sporadic pigmentary disorder characterized by hyperpigmented macules arranged in linear streaks and whorls along Blaschko's lines,typically appearing within the first few weeks of life[1],and remains a challenge to treat.Here,we report a case of LWNH and review the relevant literature to help clinicians better understand this disease. 展开更多
关键词 Blaschko lines hyperpigmented macules TREATMENT whorled nevoid hypermelanosis lwnh linear nevoid hypermelanosis whorled nevoid hypermelanosis pigmentary disorder blaschkos linestypically
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A Q-Learning Improved Particle Swarm Optimization for Aircraft Pulsating Assembly Line Scheduling Problem Considering Skilled Operator Allocation
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作者 Xiaoyu Wen Haohao Liu +6 位作者 Xinyu Zhang Haoqi Wang Yuyan Zhang Guoyong Ye Hongwen Xing Siren Liu Hao Li 《Computers, Materials & Continua》 2026年第1期1503-1529,共27页
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper... Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines. 展开更多
关键词 Aircraft pulsating assembly lines skilled operator reinforcement learning PSO reverse scheduling
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Deep Learning-Based Toolkit Inspection: Object Detection and Segmentation in Assembly Lines
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作者 Arvind Mukundan Riya Karmakar +1 位作者 Devansh Gupta Hsiang-Chen Wang 《Computers, Materials & Continua》 2026年第1期1255-1277,共23页
Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone t... Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone to errors and lacks consistency,emphasizing the need for a reliable and automated inspection system.Leveraging both object detection and image segmentation approaches,this research proposes a vision-based solution for the detection of various kinds of tools in the toolkit using deep learning(DL)models.Two Intel RealSense D455f depth cameras were arranged in a top down configuration to capture both RGB and depth images of the toolkits.After applying multiple constraints and enhancing them through preprocessing and augmentation,a dataset consisting of 3300 annotated RGB-D photos was generated.Several DL models were selected through a comprehensive assessment of mean Average Precision(mAP),precision-recall equilibrium,inference latency(target≥30 FPS),and computational burden,resulting in a preference for YOLO and Region-based Convolutional Neural Networks(R-CNN)variants over ViT-based models due to the latter’s increased latency and resource requirements.YOLOV5,YOLOV8,YOLOV11,Faster R-CNN,and Mask R-CNN were trained on the annotated dataset and evaluated using key performance metrics(Recall,Accuracy,F1-score,and Precision).YOLOV11 demonstrated balanced excellence with 93.0%precision,89.9%recall,and a 90.6%F1-score in object detection,as well as 96.9%precision,95.3%recall,and a 96.5%F1-score in instance segmentation with an average inference time of 25 ms per frame(≈40 FPS),demonstrating real-time performance.Leveraging these results,a YOLOV11-based windows application was successfully deployed in a real-time assembly line environment,where it accurately processed live video streams to detect and segment tools within toolkits,demonstrating its practical effectiveness in industrial automation.The application is capable of precisely measuring socket dimensions by utilising edge detection techniques on YOLOv11 segmentation masks,in addition to detection and segmentation.This makes it possible to do specification-level quality control right on the assembly line,which improves the ability to examine things in real time.The implementation is a big step forward for intelligent manufacturing in the Industry 4.0 paradigm.It provides a scalable,efficient,and accurate way to do automated inspection and dimensional verification activities. 展开更多
关键词 Tool detection image segmentation object detection assembly line automation Industry 4.0 Intel RealSense deep learning toolkit verification RGB-D imaging quality assurance
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Design of a wideband non-uniform microstrip line for complex impedance matching in automotive radar frequencies
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作者 ZHANG Shuang-Gen YU Tao +2 位作者 WANG Yu-Lan CHENG Zhi-Hua YAO Jian-Quan 《红外与毫米波学报》 北大核心 2025年第2期168-176,共9页
Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for co... Microstrip transmission lines connecting to the millimeter wave radar chip and antenna significantly affect the radiation efficiency and bandwidth of the antenna.Here,a wideband non-uniform wavy microstrip line for complex impedance in automotive radar frequency range is proposed.Unlike the gradient transmission line,the wavy structure is composed of periodically semi-circular segments.By adjusting the radius of the semi-circular,the surface current is varied and concentrated on the semi-circular segments,allowing a wider tunability range of the resonant frequency.The results reveal that the bandwidth of the loaded wavy transmission line antenna improves to 9.37 GHz,which is 5.81 GHz wider than that of the loaded gradient line.The gain and the half power beam width of the loaded antenna are about 14.69 dB and 9.58°,respectively.The proposed non-uniform microstrip line scheme may open up a route for realizing wideband millimeter-wave automotive radar applications. 展开更多
关键词 millimeter wave gradient line wavy transmission line broadband high gain array antenna
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Compact Ultra-Low Loss Optical True Delay Line on Thin Film Lithium Niobate
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作者 Yuan Ren Bo-Yang Nan +6 位作者 Rong-Bo Wu Yong Zheng Rui-Xue Liu Xue-Wen Wang Yun-Peng Song Min Wang Ya Cheng 《Chinese Physics Letters》 2025年第7期145-149,共5页
We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the... We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the conventional telecom band. 展开更多
关键词 conventional telecom band COMPACT transmission loss optical true delay line true delay line thin film ultra low loss lithium niobate
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China’s Sea Lines of Communication Security: A Perspective from a Holistic Approach to National Security
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作者 Wang Xu 《China International Studies》 2025年第4期31-68,共38页
Sea lines of communication(SLOCs)security has long been a strategic concern for major powers.Following the establishment of the People’s Republic of China,the country’s focus was on the traditional security aspects ... Sea lines of communication(SLOCs)security has long been a strategic concern for major powers.Following the establishment of the People’s Republic of China,the country’s focus was on the traditional security aspects of its SLOCs.Since the reform and opening-up era-and especially after the end of the Cold War-China has shifted its emphasis toward economic security.China’s SLOCs security bears on multiple dimensions of a holistic approach to national security,encompassing economic security,the safety of its citizens. 展开更多
关键词 holistic approach economic securitythe citizen safety sea lines communication slocs security national security sea lines communication security economic security
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Continuously Tunable Thin-Film Lithium Niobate Optical Delay Line with 293 ps Tuning Range
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作者 Lv-Bin Song Yong Zheng +8 位作者 Yuan Ren Bo-Yang Nan Rui-Xue Liu Hao-Zong Zhong Lin Li Min Wang Jin-Ming Chen Rong-Bo Wu Ya Cheng 《Chinese Physics Letters》 2025年第9期62-67,共6页
We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with du... We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with dual tunable couplers,where each coupler comprises two 2×2 multimode interferometers and a MZI phase-tuning section.Experimental results demonstrate continuous delay tuning from 0 to 293 ps through synchronized control of coupling coefficients,corresponding to a 4 cm path difference between interferometer arms.The measured delay range exhibits excellent agreement with theoretical predictions derived from ODL waveguide parameters.This result addresses critical challenges in integrated photonic systems that require precise temporal control,particularly for applications in optical communications and quantum information processing,where a wide tuning range is paramount. 展开更多
关键词 continuous tunable thin film lithium niobate optical delay line wide range continuous tunability delay tuning optical delay line odl unbalanced Mach Zehnder interferometer synchronized control coupling coefficientscorresponding dual tunable couplers cm path difference interfe
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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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Deep Myofascial Kinetic Lines in Horses, Comparative Dissection Studies Derived from Humans
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作者 Vibeke Sødring Elbrønd Rikke M. Schultz 《Open Journal of Veterinary Medicine》 2021年第1期14-40,共27页
Seven superficial myofascial kinetic lines have been described earlier in horses in a comparative dissection study to the human lines. The lines act as an anatomical basis for understanding locomotion, stabilization, ... Seven superficial myofascial kinetic lines have been described earlier in horses in a comparative dissection study to the human lines. The lines act as an anatomical basis for understanding locomotion, stabilization, and posture. Further dissections verified three profound equine lines comparable to those described in humans and a fourth line not described previously. Forty-four horses of different breed and gender were dissected, imaged and video recorded. The horses were euthanized due to reasons not related to this study. A Deep Ventral Line (DVL) very similar to that in the human was verified in these studies. The line spans from the insertion of the profound flexor tendon in the hindlimb to the base of the cranium and oral part of the cavities of the head. It includes the profound, hypaxial myofascial structures, the ventral coccygeal muscles, the psoas muscles, the diaphragm, the longus colli/capitis muscles and the ventral capital muscles. The inner lining of the pelvic, abdominal and thoracic cavities with all the organs, vessels and nerves are also included. The line is closely connected to the autonomic nervous system by the vagus nerve, the pelvic nerves, the sympathetic trunk and several of the prevertebral nerves and ganglia. The new line identified in this study, is a Deep Dorsal Line (DDL), which starts in the dorsal tail muscles. It comprises myofascial structures of the spinocostotransversal system from the tail to the head including the nuchal ligament. It connects to the dura mater and has a major role in controlling the motion and stabilization of the <em>Columna vertebralis</em>. Both the DDL and the DVL include the coccygeal myofascia and periosteum of the skull. Due to differences in biped and quadruped anatomy the Front Limb Adduction Line (FADL) and the Front Limb Abduction Line (FABL) differ from the human lines. The lines are identified as slings in the brachial and antebrachial regions. The FABL includes structures for abduction and internal rotation connecting to the Front Limb Retraction Line (FLRL), and the FADL structures of adduction and external rotation in close proximity to the Front Limb Protraction Line (FLPL). The front limb lines support the movement of the front limb around the “thoraco-scapula pivot joint” medially at the level of the upper third of the scapula. The DVL identified in this study is similar to the human DFL whereas the front limb lines differ somewhat from the deep human arm lines due to differences in bi- and quadruped anatomy and biomechanics. We have identified and described this new equine DDL. The lines altogether explain a profound body balance and confirm the three-dimensional equine fascial network, which is of great clinical and biomechanical importance. 展开更多
关键词 Myofascial lines Deep Ventral line Deep Dorsal line Deep Adduction line Deep Abduction line Viscero-Somatic Connections
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基于转座元件分析揭示绵羊基因组中LINE转座子元件的特性和进化
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作者 梁千千 董华娇 +4 位作者 李甜甜 张洁 杨敏 万鹏程 韩吉龙 《内蒙古农业大学学报(自然科学版)》 北大核心 2025年第6期1-8,共8页
本研究采用不同的3种方法对绵羊基因组进行注释,筛选出适合绵羊转座元件注释的方法,并进行转座元件的演化历史分析。结果表明,采用从头预测(de novo prediction)和同源预测(homology?based prediction)相结合的策略对绵羊基因组进行注... 本研究采用不同的3种方法对绵羊基因组进行注释,筛选出适合绵羊转座元件注释的方法,并进行转座元件的演化历史分析。结果表明,采用从头预测(de novo prediction)和同源预测(homology?based prediction)相结合的策略对绵羊基因组进行注释效果最佳,鉴定出绵羊基因组中转座元件占比为47.34%,其中长散布核元件(LINE)占比最高(35.34%),其余依次为长末端重复序列(LTR,5.43%)、短散布核元件(SINE,3.66%)、DNA转座元件(2.44%)和未知家族(0.56%)。LINE中的牛B型逆转录转座元件(RTE?BovB)占比达16.47%。转座元件在绵羊基因组中广泛分布,但在X染色体上富集显著,占比高达57.22%。研究通过Kimura双参数模型分析转座元件的演化历史,发现绵羊基因组经历了两次转座“爆发”事件:第1次以LINE转座元件为主,第2次则同时涉及LINE和SINE转座元件的扩增,且具有时序性。综上,LINE转座元件的持续活跃是绵羊基因组扩增的主要驱动力,且其演化历史与反刍动物的基因组进化密切相关。 展开更多
关键词 绵羊 基因组 长散布核元件(line) 基因组扩增 适应性进化
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A 2.69 ppm/℃ bandgap reference with 42 ppm/V line sensitivity for battery management system 被引量:1
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作者 Jing Wang Feixiang Zhang +2 位作者 Zhiyuan He Hui Zhang Lin Cheng 《Journal of Semiconductors》 2025年第6期31-42,共12页
This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode sche... This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode scheme with chopped op-amps and internal clock generators to eliminate op-amp offset.A low dropout regulator(LDO)and a pre-regula-tor enhance output driving and LS,respectively.Curvature compensation enhances the TC by addressing higher-order nonlinear-ity.These approaches,effective near room temperature,employs trimming at both 20 and 60°C.When combined with fixed cur-vature correction currents,it achieves an ultra-low TC for each chip.Implemented in a CMOS 180 nm process,the BGR occu-pies 0.548 mm²and operates at 2.5 V with 84μA current draw from a 5 V supply.An average TC of 2.69 ppm/℃ with two-point trimming and 0.81 ppm/℃ with multi-point trimming are achieved over the temperature range of-40 to 125℃.It accommo-dates a load current of 1 mA and an LS of 42 ppm/V,making it suitable for precise BMS applications. 展开更多
关键词 bandgap reference high precision low temperature coefficient small line sensitivity battery management system BMS
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Residual rock deformation of lined caverns for underground energy storage after air deflation considering stress path 被引量:1
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作者 Chen Xu Caichu Xia +3 位作者 Gecheng Zhang Sheng Wang Hui Lu Yingjun Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4160-4178,共19页
This study investigates the mechanical response of an underground cavern subjected to cyclic high gas pressure,aiming to establish a theoretical foundation for the design of lined rock caverns(LRCs)for energy storage ... This study investigates the mechanical response of an underground cavern subjected to cyclic high gas pressure,aiming to establish a theoretical foundation for the design of lined rock caverns(LRCs)for energy storage with high internal pressure,e.g.compressed air energy storage(CAES)underground caverns or hydrogen storage caverns.Initially,the stress paths of the surrounding rock during the excavation,pressurization,and depressurization processes are delineated.Analytical expressions for the stress and deformation of the surrounding rock are derived based on the MohreCoulomb criterion.These expressions are then employed to evaluate the displacement of cavern walls under varying qualities of surrounding rock,the contact pressure between the steel lining and the surrounding rock subject to different gas storage pressures,the load-bearing ratio of the surrounding rock,and the impact of lining thickness on the critical gas pressure.Furthermore,the deformation paths of the surrounding rock are evaluated,along with the effects of tunnel depth and diameter on residual deformation of the surrounding rock,and the critical minimum gas pressure at which the surrounding rock and the lining do not detach.The results indicate that residual deformation of the surrounding rock occurs after depressurization under higher internal pressure for higher-quality rock masses,leading to detachment between the surrounding rock and the steel lining.The findings indicate that thicker linings correspond to higher critical minimum gas pressures.However,for lower-quality surrounding rock,thicker linings correspond to lower critical minimum gas pressures.These findings will provide invaluable insights for the design of LRCs for underground energy storage caverns. 展开更多
关键词 Underground energy storage lined rock cavern(LRC) Cyclic high pressure Mechanical response Stress path
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GFRF R-CNN:Object Detection Algorithm for Transmission Lines
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作者 Xunguang Yan Wenrui Wang +3 位作者 Fanglin Lu Hongyong Fan Bo Wu Jianfeng Yu 《Computers, Materials & Continua》 SCIE EI 2025年第1期1439-1458,共20页
To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-cap... To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution images.This study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission line.The algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine details.The Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and speed.The incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s accuracy.Experimental results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster R-CNN.This highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images. 展开更多
关键词 Faster R-CNN transmission line object detection GIOU GFR
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Aerodynamics and countermeasures of train-tail swaying inside single-line tunnels 被引量:1
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作者 Yadong SONG Yanpeng ZOU +2 位作者 Yuan YAO Ting QIN Longjiang SHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期438-455,共18页
In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of v... In recent years,train-tail swaying of 160 km/h electric multiple units(EMUs)inside single-line tunnels has been heavily researched,because the issue needs to be solved urgently.In this paper,a co-simulation model of vortex-induced vibration(VIV)of the tail car body is established,and the aerodynamics of train-tail swaying is studied.The simulation results were confirmed through a field test of operating EMUs.Furthermore,the influence mechanism of train-tail swaying on the wake flow field is studied in detail through a wind-tunnel experiment and a simulation of a reduced-scaled train model.The results demonstrate that the aerodynamic force frequency(i.e.,vortex-induced frequency)of the train tail increases linearly with train speed.When the train runs at 130 km/h,with a small amplitude of train-tail swaying(within 10 mm),the vortex-induced frequency is 1.7 Hz,which primarily depends on the nose shape of the train tail.After the tail car body nose is extended,the vortex-induced frequency is decreased.As the swaying amplitude of the train tail increases(exceeding 25 mm),the separation point of the high-intensity vortex in the train wake shifts downstream to the nose tip,and the vortex-induced frequency shifts from 1.7 Hz to the nearby car body hunting(i.e.,the primary hunting)frequency of 1.3 Hz,which leads to the frequency-locking phenomenon of VIV,and the resonance intensifies train-tail swaying.For the motor vehicle of the train tail,optimization of the yaw damper to improve its primary hunting stability can effectively alleviate train-tail swaying inside single-line tunnels.Optimization of the tail car body nose shape reduces the amplitude of the vortex-induced force,thereby weakening the aerodynamic effect and solving the problem of train-tail swaying inside the single-line tunnels. 展开更多
关键词 train tail swaying wind tunnel experiment field test single line tunnels AERODYNAMICS co simulation electric multiple units emus inside vortex induced vibration
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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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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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Quick Author Guideline for OIL CROP SCIENCE
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《Oil Crop Science》 2025年第2期F0003-F0003,共1页
Manuscript Text and figures combined into a single file with page and line numbers up to3 MB in size in txt,doc,docx or tex files.Prepares your manuscript in the following order:Title page,Abstract,Introduction,Materi... Manuscript Text and figures combined into a single file with page and line numbers up to3 MB in size in txt,doc,docx or tex files.Prepares your manuscript in the following order:Title page,Abstract,Introduction,Materials and Methods,Results,Discussion,Acknowledgments,References,Tables,Figure Legends and Figures.Provide Cover letter and Supplementary Material(if necessary)at the same time. 展开更多
关键词 line oil crop text PAGE cover letter supplementary material SCIENCE MANUSCRIPT
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Establishment of a Leopard Coral Grouper(Plectropomus leopardus)Fin Cell Line(PLF):A Robust Tool for Investigating Viral Pathogenesis and Host Immunity
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作者 CHEN Huiquan XIAO Bingyan +2 位作者 CHEN Leshi YI Meisheng JIA Kuntong 《Journal of Ocean University of China》 2025年第6期1737-1746,共10页
Leopard coral grouper(Plectropomus leopardus)is a commercially important marine fish species.It is important to study how to prevent it from infecting with various viruses.In this study,we established and characterize... Leopard coral grouper(Plectropomus leopardus)is a commercially important marine fish species.It is important to study how to prevent it from infecting with various viruses.In this study,we established and characterized a new cell line derived from the fin tissue of leopard coral grouper(PLF).The PLF cells were cultured for more than 55 passages.Cytochrome B gene sequencing confirmed the origin of the PLF cells is P.leopardus.Immunostaining against cytokeratin indicated that the PLF cells predominantly consist of epithelial cells.The chromosome number of PLF was 48.The cells grew well in Dulbecco's modified Eagle's medium(DMEM)supplemented with 10%–20%fetal bovine serum(FBS)at temperature between 20–28℃,with the highest growth rate at28℃.Transfection with pEGFP-N3 plasmid showed the transfection efficiency was about 35%.Virus susceptibility tests revealed that PLF cells are susceptible to red-spotted grouper nervous necrosis virus(NNV)and viral hemorrhagic septicemia virus(VHSV),and viral proliferation was confirmed by qRT-PCR and western blot.The altered expressions of immune-related genes TBK1,IRF3,and Mx after NNV and VHSV infections suggested that PLF cells can mount an immune response to fish viruses.Thus the PLF cells can be employed for studying virus-host interactions and developing antiviral strategies. 展开更多
关键词 Plectropomus leopardus cell line RGNNV VHSV virus susceptibility
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