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Inverse Scattering Problem on a Star-shaped Graph with Robin Boundary Conditions
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作者 WU Dongjie 《数学进展》 北大核心 2026年第2期369-384,共16页
This work deals with an inverse scattering problem for the Schrodinger operator on a star-shaped graph with one semi-infinite branch.Using the high-frequency asymptotic behaviour of the reflection coefficient,first we... This work deals with an inverse scattering problem for the Schrodinger operator on a star-shaped graph with one semi-infinite branch.Using the high-frequency asymptotic behaviour of the reflection coefficient,first we provide the identifiability of the geometry of this star-shaped graph:the number of edges and their lengths.Under some assumptions on the geometry of the graph,the main result states that the measurement of one reflection coefficient,together with the scattering data corresponding to the infinite branch,associated with Robin boundary conditions at the external nodes of the graph,can uniquely determine the parameters of the boundary conditions and the potentials on the whole interval which is already known in a half-interval. 展开更多
关键词 inverse scattering Schrödinger operator reflection coefficient
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Thermodynamic Correlation Between Surface Carboxyl Configuration and Wettability
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作者 GUO Zhuohuan WANG Dayang 《高等学校化学学报》 北大核心 2026年第1期255-266,共12页
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at... In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces. 展开更多
关键词 Polyacrylic acid film Hydrogen bonding Attenuated total reflectance Fourier-transform infrared spectroscopy Quantitative carboxyl configuration Polar component of surface energy
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Color of the Year 2026: Cloud Dancer, a hue of serenity and space
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《China Textile》 2026年第1期54-55,共2页
The Pantone Color of the Year 2026,PANTONE 11-4201 Cloud Dancer,has been introduced as a soft,lofty white symbolizing calm and clarity in an increasingly noisy world.This gentle shade invites a sense of peace and spac... The Pantone Color of the Year 2026,PANTONE 11-4201 Cloud Dancer,has been introduced as a soft,lofty white symbolizing calm and clarity in an increasingly noisy world.This gentle shade invites a sense of peace and spaciousness,encouraging focus and creating room for creativity and reflection.Cloud Dancer embodies a desire for simplicity and renewal-a blank canvas that allows our minds to wander and new ideas to take shape.Its expansive presence fosters environments where tranquility meets inspiration,offering visual calm that supports wellbeing and mental lightness. 展开更多
关键词 pantone color SERENITY SPACE clarity creativity blank canvas reflection cloud dancerhas
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Domestication Leads to Lower Dorsal Crypsis in Black-spotted Frogs (Pelophylax nigromaculatus)
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作者 Chaoyu SU Lingsen CAO +4 位作者 Yiming WU Keshan Ken MAHABIR Yanbo SUN Long JIN Wenbo LIAO 《Asian Herpetological Research》 2026年第1期47-52,共6页
A primary anti-predator adaptation is crypsis, in which animals reduce their visibility to predators, often through camouflage, to lower the risk of predation. Alternatively, prey species may employ strategies such as... A primary anti-predator adaptation is crypsis, in which animals reduce their visibility to predators, often through camouflage, to lower the risk of predation. Alternatively, prey species may employ strategies such as aposematism, which advertises unpalatability, or mimicry, which involves imitating other organisms. Because domestic animals typically experience reduced predation pressure compared with their wild counterparts, they are expected to exhibit less developed cryptic coloration. To test this prediction, we compared dorsal and ventral crypsis between domestic and wild black-spotted frogs(Pelophylax nigromaculatus) using reflectancemeasurement methods. Our results showed that domestic males displayed significantly weaker dorsal crypsis than wild males. In contrast, no statistically significant difference in dorsal crypsis was observed between domestic and wild females. These findings suggest that the reduction in dorsal crypsis among domestic males may be attributable to relaxed predation pressure and shifts in dietary resources within human-modified environments. 展开更多
关键词 black-spotted frogs CRYPSIS DOMESTICATION reflectance spectra
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An analytical study for detonation wave boundary layer interactions under reflections
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作者 Hao YAN Xin HAN +2 位作者 Haochen XIONG Chongguang SHI Yancheng YOU 《Chinese Journal of Aeronautics》 2026年第2期178-201,共24页
Numerical simulations and theoretical models are developed in this paper for the Detonation-Wave/Boundary-Layer Interactions(DWBLIs)under reflections.Transient flow fields demonstrate the highly non-stationarity of th... Numerical simulations and theoretical models are developed in this paper for the Detonation-Wave/Boundary-Layer Interactions(DWBLIs)under reflections.Transient flow fields demonstrate the highly non-stationarity of the DWBLIs when Mach Reflection(MR)occur,and subsequent analyses show that the subsonic region introduced by the boundary layer exacerbates the instability.Further quantitative analyses show that viscosity has little effect on propulsive performance and the separation wave can be considered as an oblique detonation wave.Influence parameters to DWBLIs such as combustion chamber height,incoming Mach number,equivalence ratio,and inlet channel length are categorized and studied.Besides simulations,theoretical analytical modeling is established for Regular Reflection(RR)and MR of DWBLIs.Multiple formulas for the separation zone length are obtained according to the mass conservation under different transformation type between inviscid and viscid reflections.Comparison with the numerical simulations verifies the validity of the model and it can be further generalized to the curved DWBLIs.The developed model makes the theoretical solution process of DWBLIs possible and provides the key foundation for further analysis and solution. 展开更多
关键词 Boundary layer interaction Detonation wave Hypersonic flow REFLECTION VISCOSITY
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Heterolayered Carbonized MXene/Polyimide Aerogel for Low-Reflection Electromagnetic Interference Shielding and Multi-Spectrum Compatible Protection
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作者 Shan Zhang Chen‑Ming Liang +5 位作者 Lu Zhou Juntao Wu Martin CKoo Zongxin Wu Yun‑Tian Chen Guang‑Sheng Wang 《Nano-Micro Letters》 2026年第6期702-716,共15页
The advancement of next-generation high-frequency communication systems and stealth detection technologies necessitate the development of efficient,multi-spectrum compatible shielding materials.However,the achievement... The advancement of next-generation high-frequency communication systems and stealth detection technologies necessitate the development of efficient,multi-spectrum compatible shielding materials.However,the achievement of simultaneous high efficiency and low reflectivity across microwave,terahertz,and infrared spectra remains a formidable challenge.Herein,a carbonized MXene/polyimide(C-MXene/PI)aerogel material integrating a spatially coupled hierarchically anisotropic structure with stepwise conductivity gradients was constructed.Electromagnetic waves propagate through the top-down vertical disordered horizontal architecture and progressive conductivity gradient of C-MXene/PI aerogel,undergoing stepwise absorption-dissipation-re-dissipation processes.The C-MXene/PI aerogel exhibits an average electromagnetic interference(EMI)shielding effectiveness of91.0 dB in X-band and a reflection coefficient of 0.40.In the terahertz frequency band,the average EMI shielding performance reaches66.2 dB with a reflection coefficient of 0.33.Furthermore,the heterolayered porous architecture of C-MXene/PI aerogels exhibits low thermal conductivity and reduced infrared emissivity,enabling exceptional infrared stealth capability across the 2-16μm wavelength spectrum.This study provides an feasible strategy for constructing low-reflectivity multi-spectrum compatible shielding materials. 展开更多
关键词 Heterolayered Electromagnetic interference shielding Multi-spectrum Low reflection High efficiency
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Collaborative Assessment of Reflectivity Consistency between FY-3G Precipitation Measurement Radar and Ground-Based Radars
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作者 Chunyan ZHANG Heng HU +4 位作者 Jiashan ZHU Qinqiang ZHOU Lei WU Jianyong LI Xuan ZHU 《Advances in Atmospheric Sciences》 2026年第5期1065-1078,共14页
FY-3G is the first polar-orbiting satellite equipped with a precipitation measurement radar(PMR)operating at Ku-andKa-band frequencies in China.In this study,we compare the reflectivity data from the FY-3G PMR Ku prod... FY-3G is the first polar-orbiting satellite equipped with a precipitation measurement radar(PMR)operating at Ku-andKa-band frequencies in China.In this study,we compare the reflectivity data from the FY-3G PMR Ku product and groundbasedradars(GRs)during 2024.Also,the FY-3G PMR is used as a third-party reference to evaluate the reflectivityconsistency among different GRs.The FY-3G PMR and GRs share similarities in their general distribution,characteristics,and intensity of reflectivity in strong precipitation cloud systems,though the former presents less detailed system structure.Systematic deviations between the FY-3G PMR and GRs and between GRs are comparable,albeit the reflectivity of the FY-3G PMR is generally slightly stronger than that of GRs(especially X-band GRs),with a mean bias ranging from 0.7 to 1.7dB.S-band GRs exhibit the smallest systematic deviation(STD=3.09 dB)from the FY-3G PMR,whereas the X-band GRsshow the largest(STD=3.61 dB),indirectly indicating the highest internal consistency among S-band GRs and the lowestamong X-band GRs.Besides,both S-and C-band GRs display similar deviations when paired with the FY-3G PMR as wellas when paired with their adjacent S/C-band GRs,suggesting good consistency between these two bands.In contrast,XbandGRs exhibit relatively poor consistency with S-band GRs and the FY-3G PMR,showing a deviation ranging from 3.0to 4.6 dB. 展开更多
关键词 REFLECTIVITY deviation CONSISTENCY FY-3G PMR ground-based radars
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Metacognition Inspired Reflective Chain-of-Thought for Knowledge-Based VQA
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作者 Zhongfan Sun Kan Guo +1 位作者 Yongli Hu Yong Zhang 《Computers, Materials & Continua》 2026年第4期1909-1933,共25页
Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretra... Knowledge-based VisualQuestion Answering(VQA)requires the integration of visual information with external knowledge reasoning.Existing approaches typically retrieve information from external corpora and rely on pretrained language models for reasoning.However,their performance is often hindered by the limited capabilities of retrievers and the constrained size of knowledge bases.Moreover,relying on image captions to bridge the modal gap between visual and language modalities can lead to the omission of critical visual details.To address these limitations,we propose the Reflective Chain-of-Thought(ReCoT)method,a simple yet effective framework inspired by metacognition theory.ReCoT effectively activates the reasoning capabilities ofMultimodal Large LanguageModels(MLLMs),providing essential visual and knowledge cues required to solve complex visual questions.It simulates a metacognitive reasoning process that encompasses monitoring,reflection,and correction.Specifically,in the initial generation stage,an MLLM produces a preliminary answer that serves as the model’s initial cognitive output.During the reflective reasoning stage,this answer is critically examined to generate a reflective rationale that integrates key visual evidence and relevant knowledge.In the final refinement stage,a smaller language model leverages this rationale to revise the initial prediction,resulting in amore accurate final answer.By harnessing the strengths ofMLLMs in visual and knowledge grounding,ReCoT enables smaller language models to reason effectively without dependence on image captions or external knowledge bases.Experimental results demonstrate that ReCoT achieves substantial performance improvements,outperforming state-of-the-art methods by 2.26%on OK-VQA and 5.8%on A-OKVQA. 展开更多
关键词 Knowledge-based VQA METACOGNITION reflective chain-of-thought answer refinement
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A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
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作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 Concept analysis Intensive Care Unit NURSING Positive environment Reflective supervision
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The Soul of Geography:Bojie Fu’s vision for science and humanity
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作者 Michael E Meadows 《Geography and Sustainability》 2026年第1期253-254,共2页
In an academic environment increasingly shaped by metrics and the imperatives of“publish or perish”,it is rare to encounter a leading scientist willing to interweave personal narrative with conceptual reflection.The... In an academic environment increasingly shaped by metrics and the imperatives of“publish or perish”,it is rare to encounter a leading scientist willing to interweave personal narrative with conceptual reflection.The Soul of Geography by Fu(2025)achieves precisely this.The book resists simple categorisation:it is neither a conventional monograph nor a memoir,but rather a hybrid text that integrates autobiography,disciplinary reflection,and scientific arguments.In doing so,Fu articulates not only the trajectory of his own career but also a vision of geography as a discipline of theoretical depth and practical relevance. 展开更多
关键词 scientific arguments hybrid text AUTOBIOGRAPHY GEOGRAPHY disciplinary reflection publish perish theoretical depth metrics
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From classroom to bedside:nursing students'perspectives on implementing a best practice guideline for developing and sustaining nursing leadership
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作者 Kara Cabangcalan Alaa Daloul +1 位作者 Safiya Mir Elham Al-Omari 《Frontiers of Nursing》 2026年第1期83-95,共13页
Objective:To explore the application of the Registered Nurses'Association of Ontario(RNAO)Best Practice Guideline(BPG)for Developing and Sustaining Nursing Leadership through the lens of nursing students transitio... Objective:To explore the application of the Registered Nurses'Association of Ontario(RNAO)Best Practice Guideline(BPG)for Developing and Sustaining Nursing Leadership through the lens of nursing students transitioning from classroom learning to clinical practice.Through this reflection,the authors hope to inspire and empower future nursing leaders to champion innovation,resilience,and excellence in healthcare.Methods:By integrating evidence-based leadership principles,the authors reflect on their personal experiences,challenges,and successes in implementing these guidelines in real-world settings.Results:The paper highlights the significance of leadership in fostering healthy work environments and improving patient outcomes,emphasizing the role of nursing students as emerging leaders.Practical strategies for applying BPG,the RNAO BPG suggests leadership skills on professional development,and recommendations for embedding leadership principles into nursing education and practice are discussed.Conclusions:Implementing nursing leadership from the beginning of a nursing student's journey is vital for shaping the next generation of healthcare leaders.By integrating leadership principles early in nursing education,students can develop the skills needed to navigate clinical challenges,collaborate effectively with healthcare teams,and advocate for positive change.Starting with leadership guidelines in nursing school ensures that future nurses are equipped to foster supportive work environments,improve patient outcomes,and drive innovation from the very start of their careers,making leadership an inherent part of their professional identity. 展开更多
关键词 best practice guideline evidence-based practice nursing education nursing leadership nursing students REFLECTION
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Electric-type Stern-Gerlach effect
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作者 Jiang-Lin Zhou Zou-Chen Fu +1 位作者 Choo Hiap Oh Jing-Ling Chen 《Chinese Physics B》 2026年第1期219-224,共6页
The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Th... The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Thus,the conventional SG experiment can be viewed as a magnetic-type spin effect.In this work,we successfully generalize the SG effect from magnetic-type to electric-type by solving Dirac's equation with a potential barrier,revealing an extraordinary spin effect.Beams of Dirac particles can be regarded as matter waves.Based on Dirac's equation,we obtain the explicit forms of the incident,reflected,and transmitted waves.The electric-type SG effect shows that the reflected and transmitted waves can exhibit notable spatial shifts,which depend on the spin direction and the incident angle of the wave.The electrictype SG effect has potential applications for separating Dirac particles with different spin directions and for estimating the spin direction of Dirac particles.Some discussions related to the interaction between spin and the electric field are also presented. 展开更多
关键词 Dirac's electron reflection and transmission spin Stern-Gerlach experiment electric-type Stern-Gerlach effect
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Energy Efficiency and Total Mission Completion Time Tradeoff in Multiple UAVs-Mounted IRS-Assisted Data Collection System
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作者 Hong Zhao Hongbin Chen +2 位作者 Zhihui Guo Ling Zhan Shichao Li 《Computers, Materials & Continua》 2026年第2期1849-1873,共25页
UAV-mounted intelligent reflecting surface(IRS)helps address the line-of-sight(LoS)blockage between sensor nodes(SNs)and the fusion center(FC)in Internet of Things(IoT).This paper considers an IoT assisted by multiple... UAV-mounted intelligent reflecting surface(IRS)helps address the line-of-sight(LoS)blockage between sensor nodes(SNs)and the fusion center(FC)in Internet of Things(IoT).This paper considers an IoT assisted by multiple UAVs-mounted IRS(U-IRS),where the data from ground SNs are transmitted to the FC.In practice,energy efficiency(EE)and mission completion time are crucial metrics for evaluating system performance and operational costs.Recognizing their importance during data collection,we formulate a multi-objective optimization problem to maximize EE and minimize total mission completion time simultaneously.To characterize this tradeoff while considering optimization objective consistency,we construct an optimization problem that minimizes the weighted sum of the total mission completion time and the reciprocal of EE.Due to the non-convex nature of the formulated problem,obtaining optimal solutions is generally challenging.To tackle this issue,we decompose it into three subproblems:UAV-SN association,number of reflecting elements allocation,andUAVtrajectory optimization.An iterative algorithmcombining genetic algorithm,CS-BJ algorithm,and successive convex approximation technique is proposed to solve these sub-problems.Simulation results demonstrate that when the transmitted data amount is 10 and 30Mbits,compared to the static collection benchmark(the UAV hovers directly above each SN),the EE of the proposed method improves by more than 10.4% and 5.2%,while the total mission completion time is reduced by more than 5.4% and 3.3%,respectively. 展开更多
关键词 Unmanned aerial vehicle intelligent reflecting surface energy efficiency totalmission completion time optimization
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Steady-state fretting response governed by periodic stress variations induced by oblique excitation
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作者 Shenghao Lu Huan Wang Shaoze Yan 《Chinese Physics B》 2026年第1期535-547,共13页
This study investigates the mechanisms of friction-induced vibration under periodic variations in stress distribution using an improved fretting friction model.A fretting friction test system integrated with a total r... This study investigates the mechanisms of friction-induced vibration under periodic variations in stress distribution using an improved fretting friction model.A fretting friction test system integrated with a total reflection method was developed to analyze interfacial contact behavior under dynamic loading conditions.An improved fretting friction model was established,incorporating three critical nonlinear parameters:the hysteretic friction coefficient,tangential stiffness fluctuations,and stress distribution.Through systematic validation,the model demonstrates high-fidelity replication of experimental steady-state amplitude-frequency responses.Key findings reveal that non-uniform stress distribution governs irregularities in the vibration response,and increased uniformity intensifies stick-slip instabilities.Near the stick-slip transition threshold,distinct vibration anomalies emerge due to the coupled effects of stress heterogeneity,friction hysteresis,and stiffness variations during state transitions.Furthermore,the magnitude of the normal contact force systematically alters the dominant interfacial contact mechanism.The different interfacial contact states at various frequencies lead to distinct steady-state responses.This shift elevates resonance frequencies and amplifies higher-order resonant peaks.The fretting friction model provides a predictive framework for vibration control under dynamic interfacial loading. 展开更多
关键词 total reflection method stress distribution the fretting friction model normal force STICK-SLIP
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Effects of end caps of cylindrical casing on fragment velocity distribution
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作者 Yueguang Gao Jianping Fu +3 位作者 Siyu Wu Xuke Lan Kai Ren Rui Yang 《Defence Technology(防务技术)》 2026年第3期377-394,共18页
Fragment velocity distribution is an important parameter affecting the terminal effects of warheads.The rarefaction wave,end cap,and its confinement state can significantly affect the fragmentation of the cylindrical ... Fragment velocity distribution is an important parameter affecting the terminal effects of warheads.The rarefaction wave,end cap,and its confinement state can significantly affect the fragmentation of the cylindrical charge casing.Most of the existing studies have performed experiments and simulations considering the rarefaction wave and unfixed end caps;research on fixed end caps and sufficient theoretical explanations are limited.In this work,the effects of rarefaction waves,end caps,and their fixed states,on the fragment velocity distribution,were studied via experimentation and simulation,and reasonable theoretical explanations were provided.The results show that the rarefaction wave and end caps affect the fragment velocity by changing the pressure states of the detonation products.At the initiation end,the fragment velocities of casings with unfixed initiation ends are 33.3%(300 m/s)greater than that of casings without end caps,because of the weakening of the attenuation effect of the rarefaction wave.The fragment velocities of the casings with fixed initiation ends are 8.3%(100 m/s)greater than that of casings with unfixed initiation ends.At the non-initiation end,the fragment velocities are 24.8%(297 m/s)greater than that of a casing without end caps,and the reflecting shock wave generated by the fixed non-initiation end increases the fragment velocity by 7.3%(113 m/s),compared to the theoretical velocity.This work provides a basis for the structural design and analysis of the terminal effects of warheads. 展开更多
关键词 Fragment velocity Numerical simulation X-ray radiography Axial rarefaction waves Reflect shock wave Cylindrical casing
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Geostationary Satellite–Based Proxy Radar Observations:Expanding Coverage for Storm Tracking
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作者 Yunheng XUE Mengxue XU +4 位作者 Jun LI Bo LI Min MIN Peng ZHANG Ling YANG 《Advances in Atmospheric Sciences》 2026年第2期307-320,共14页
Ground-based radar is the primary means by which severe storms are monitored and tracked;however, due to limited coverage, important data is often missed over ocean and mountainous areas. On the other hand, geostation... Ground-based radar is the primary means by which severe storms are monitored and tracked;however, due to limited coverage, important data is often missed over ocean and mountainous areas. On the other hand, geostationary(GEO)weather satellites provide continuous observations with seamless coverage with advanced imager, despite their limited capability to penetrate clouds. Combining satellite and ground-radar observations could exploit the advantages of both techniques, providing tracking capability close to that of ground radar while maintaining full spatial coverage. This study presents a novel method called Multi-dimensional satellite Observation information for Radar Estimation(MORE) to reconstruct radar composite reflectivity(CREF). Deep learning techniques are important components of MORE for estimating CREF from China's Fengyun-4B(FY-4B) GEO satellite observations. Two models are developed: an infraredonly(IR-Single) model available for all times, and a visible-infrared(VIS+IR) model for daytime applications. These models incorporate multi-dimensional satellite observation information, including temporal, spatial, spectral, and viewing angle information, to enhance the accuracy of radar echo reconstruction. Results demonstrate that the VIS+IR model outperforms the IR-Single model, and both models achieves a root-mean-square error(RMSE) of less than 6 dBZ and a coefficient of determination(R~2) of greater than 0.7. The models effectively reconstruct radar echoes, including strong echoes exceeding 50 dBZ, and show good agreement with precipitation data in radar-blind areas. This study offers a valuable solution for severe weather monitoring and tracking in regions lacking ground-based radar observations, and provides a potential tool for enhanced data assimilation in numerical weather prediction(NWP) models. 展开更多
关键词 radar composite reflectivity FY-4B deep learning severe weather
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Waveform-matching reverse time migration for local earthquakes
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作者 Lanshu Bai Qingju Wu Ruiqing Zhang 《Earthquake Science》 2026年第2期125-139,共15页
With the increasing use of passive seismic data,developing seismic reflection imaging methods based on passive data is of considerable practical significance.This study presents a waveform-matching reverse time migrat... With the increasing use of passive seismic data,developing seismic reflection imaging methods based on passive data is of considerable practical significance.This study presents a waveform-matching reverse time migration for the primary reflected data from local earthquakes.In order to mitigate inconsistencies in frequency band and energy across earthquakes of different magnitudes,we first establish reference seismic waveform with standardized dominant frequency and magnitude.A matching operator is derived for each event by matching its waveforms with the reference waveform.This operator is then applied via convolution to all waveforms,producing standardized seismic waveforms with consistent wavelet features.The reshaped waveforms are then subjected to reverse time migration using an impedance imaging condition for primary reflections.To suppress strong energy interference near the hypocenters,both illumination compensation and three-dimensional Smoothed Spherical Mask centered on each source are used.Numerical tests using both simple two-layer model and fault-containing model demonstrate that the new method is robust and effective.The reverse time migration of primary reflected data of local earthquakes accurately images underground impedance boundaries such as stratum interfaces and fault planes,showing its promise for future application in seismically active fault zones. 展开更多
关键词 passive seismic data local earthquake waveform matching reverse time migration primary reflected data
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Analytical solution for longitudinal responses of tunnels under combined effects of seismic waves and strike-slip faulting
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作者 Jie Tang Manchao He +2 位作者 Yafei Qiao Hanbing Bian Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1266-1289,共24页
Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analyt... Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analytical solution to determine the longitudinal mechanical responses of tunnels subjected to the combined effects of seismic waves and strike-slip faulting.Adopting the elastic springbeam model,the seismic waves are modelled as shear horizontal(SH)waves and the fault dislocation follows an S-shaped pattern;the superposition principle for free-fielddisplacements caused by both effects is assumed.In addition,the transmission and reflectionof seismic waves at the fault-rock geological interface and the tangential contact conditions at the tunnel-rock interface are considered.The analytical model is validated against numerical simulations,confirmingits accuracy in calculating tunnel responses.Moreover,a parametric study is conducted to evaluate the impact of key factors,including fault displacement,fault zone width,fault dip angle,earthquake frequency,rock conditions,tunnel lining stiffness,and tangential contact conditions,on tunnel responses.Compared with each effect alone,the combined effects of seismic waves and strike-slip faulting significantlychange the tunnel deformation and internal forces,leading to increased tunnel responses,especially within the fault zone and near the fault-rock interfaces.Depending on specificparameters,tunnel responses can be classifiedinto seismic-dominated,faulting-dominated,and seismic-faulting coupled responses on the basis of the relative contributions of each effect.The proposed analytical solution can be applied to quickly predict the longitudinal mechanical behaviour of tunnels under such combined effects in engineering applications. 展开更多
关键词 Strike-slip faulting Longitudinal tunnel response Analytical solution Seismic waves Wave transmissions and reflections
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Contrastive learning for data-efficient substrate deoxidation monitoring in edge-side adaptive molecular beam epitaxy systems
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作者 Yuehao Li Chao Shen +6 位作者 Wenkang Zhan Bo Xu Yazhou Yang Xu Zhang Hongchang Wang Chao Zhao Haifang Jian 《Journal of Semiconductors》 2026年第3期28-37,共10页
Accurate temperature control and effective oxide removal are essential for achieving high-quality epitaxial growth in molecular beam epitaxy(MBE).However,traditional methods often rely on manual identification of refl... Accurate temperature control and effective oxide removal are essential for achieving high-quality epitaxial growth in molecular beam epitaxy(MBE).However,traditional methods often rely on manual identification of reflection high-energy electron diffraction(RHEED)patterns.This process is heavily influenced by the grower’s experience,leading to issues with reproducibility and limiting the potential for automation.In this report,we propose an unsupervised learning framework for realtime RHEED analysis during the deoxidation process.By incorporating temporal similarity constraints into contrastive learning,our model generates smooth and interpretable feature trajectories that illustrate transitions in the deoxidation state,thus eliminating the need for manual labeling.The model,pre-trained using grouped contrastive loss,shows significant improvement in RHEED feature boundary discrimination and localization of critical regions.We evaluated its generalizability through two transfer learning strategies:calibration-free clustering and few-shot fine-tuning.The pre-trained model achieved a clustering accuracy of 88.1%for GaAs deoxidation samples without additional labels and reached an accuracy of 94.3%to 95.5%after fine-tuning with just five sample pairs across GaAs,Ge,and InAs substrates.This framework is optimized for resource-constrained edge devices,allowing for real-time,plug-and-play integration with existing MBE systems and swift adaptation across various materials and equipment.This work paves the way for greater automation and improved reproducibility in semiconductor manufacturing. 展开更多
关键词 contrastive learning molecular beam epitaxy real-time control reflection high-energy electron diffraction
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Synthesis and Design of Generalized Strongly Coupled Resonator Quartet Combline Filters with Redundant Resonance
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作者 Xiong Zhi’ang Fan Jiyuan +3 位作者 Zhao Ping Zhou Jinzhu Shen Nan Wu Qingqiang 《ZTE Communications》 2026年第1期88-96,共9页
This article proposes a generalized strongly coupled resonator quartet(GSCRQ)filter along with its synthesis approach.By introducing out-of-band reflection zeros(RZs),the proposed GSCRQ can generate a transmission zer... This article proposes a generalized strongly coupled resonator quartet(GSCRQ)filter along with its synthesis approach.By introducing out-of-band reflection zeros(RZs),the proposed GSCRQ can generate a transmission zero on each side of the passband without negative couplings.The coupling coefficients in this coupling structure change with the positions of the out-of-band RZs.Thus,the GSCRQ configuration admits flexible design solutions.For GSCRQ coaxial combline filters,all couplings can be implemented as inductive couplings,simplifying the design and manufacturing process.In this article,a 6-2 filter in the GSCRQ configuration is synthesized and designed.The simulated results of the designed filter agree very well with the theoretical characteristics. 展开更多
关键词 filter synthesis generalized strongly coupled resonator quartets(GSCRQ) out-of-band reflection zero transmission zero
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