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Transmission property of one-dimensional Dirac-semimetal-defected photonic crystal in terahertz multi-bandgap
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作者 Ji-Kai Wang Li Jiang +1 位作者 Xue-Fei Yang Ji-He Zhao 《Chinese Physics B》 2026年第1期498-505,共8页
A symmetrical one-dimensional(1D)photonic crystal structure with a Dirac-emimetal-defected layer is proposed.The material properties of the Dirac semimetal are governed by three key parameters:Fermi level,Fermi veloci... A symmetrical one-dimensional(1D)photonic crystal structure with a Dirac-emimetal-defected layer is proposed.The material properties of the Dirac semimetal are governed by three key parameters:Fermi level,Fermi velocity,and degeneracy factor.Simulation results demonstrate that the proposed structure generates multiple photonic bandgaps within the THz frequency range.In the low-THz region,pronounced resonant transmission peaks emerge,enabling near-perfect filtering performance.The positions of these defect modes can be dynamically tuned by adjusting the Fermi level and degeneracy factor.In mid-and high-THz frequency bands,the Dirac semimetal begins to exhibit metallic behavior,leading to attenuation of the transmission peaks and the appearance of absorption.The elevation of the Fermi level delays the critical threshold for the transition from the dielectric state to the metallic state,while an increase in Fermi velocity suppresses metallic behavior.Therefore,enhancing both the Fermi level and Fermi velocity contributes to strengthening the defect peak intensity.Conversely,increasing the degeneracy factor strengthens the metallic characteristics,thereby disrupting the high-frequency photonic bandgap.Notably,the defect layer thickness and incident angle exert significant influence on the transmission behavior:a larger incident angle causes the defect peak to shift toward higher frequencies and reduces its intensity,whereas a thicker defect layer shifts the defect peak toward lower frequencies.The modulation effects of both parameters become more pronounced as frequency increases.Compared with conventional photonic crystals,our work can provide a tunable structure over transmission properties,offering novel strategies for designing tunable filters and optical sensors. 展开更多
关键词 one-dimensional photonic crystal Dirac semimetal TUNABILITY THz
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Infrared spectroscopic analysis of O-H bond dynamics in one-dimensional confined water and bulk water
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作者 ZHANG Lei WANG Tian-Qi FAN Yan-Ping 《红外与毫米波学报》 北大核心 2025年第1期78-85,共8页
In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are c... In sub nanometer carbon nanotubes,water exhibits unique dynamic characteristics,and in the high-frequency region of the infrared spectrum,where the stretching vibrations of the internal oxygen-hydrogen(O-H)bonds are closely related to the hydrogen bonds(H-bonds)network between water molecules.Therefore,it is crucial to analyze the relationship between these two aspects.In this paper,the infrared spectrum and motion characteristics of the stretching vibrations of the O-H bonds in one-dimensional confined water(1DCW)and bulk water(BW)in(6,6)single-walled carbon nanotubes(SWNT)are studied by molecular dynamics simulations.The results show that the stretching vibrations of the two O-H bonds in 1DCW exhibit different frequencies in the infrared spectrum,while the O-H bonds in BW display two identical main frequency peaks.Further analysis using the spring oscillator model reveals that the difference in the stretching amplitude of the O-H bonds is the main factor causing the change in vibration frequency,where an increase in stretching amplitude leads to a decrease in spring stiffness and,consequently,a lower vibration frequency.A more in-depth study found that the interaction of H-bonds between water molecules is the fundamental cause of the increased stretching amplitude and decreased vibration frequency of the O-H bonds.Finally,by analyzing the motion trajectory of the H atoms,the dynamic differences between 1DCW and BW are clearly revealed.These findings provide a new perspective for understanding the behavior of water molecules at the nanoscale and are of significant importance in advancing the development of infrared spectroscopy detection technology. 展开更多
关键词 one-dimensional confined water infrared spectroscopy hydrogen bonds
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Density distribution of ground state of one-dimensional Bose gas with dipole interaction
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作者 Shuchang Hao Yajiang Hao 《Chinese Physics B》 2025年第3期245-249,共5页
Using the Bose-Fermi mapping method,we obtain the exact ground state wavefunction of one-dimensional(1D)Bose gas with the zero-range dipolar interaction in the strongly repulsive contact interaction limit.Its ground s... Using the Bose-Fermi mapping method,we obtain the exact ground state wavefunction of one-dimensional(1D)Bose gas with the zero-range dipolar interaction in the strongly repulsive contact interaction limit.Its ground state density distributions for both repulsive and attractive dipole interactions are exhibited.It is shown that in the case of the finite dipole interaction the density profiles do not change obviously with the increase of dipole interaction and display the typical shell structure of Tonks-Girardeau gases.As the repulsive dipole interaction is greatly strong,the density decreases at the center of the trap and displays a sunken valley.As the attractive dipole interaction increases,the density displays more oscillations and sharp peaks appear in the strong attraction limit,which mainly originate from the atoms occupying the low single particle levels. 展开更多
关键词 Bose gas one-dimensional dipole interaction
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The advanced development of one-dimensional transition metal dichalcogenide nanotubes:From preparation to application
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作者 Fengshun Wang Huachao Ji +6 位作者 Zefei Wu Kang Chen Wenqi Gao Chen Wang Longlu Wang Jianmei Chen Dafeng Yan 《Chinese Chemical Letters》 2025年第5期187-197,共11页
Two-dimensional(2D)transition metal sulfides(TMDs)are emerging and highly well received 2D materials,which are considered as an ideal 2D platform for studying various electronic properties and potential applications d... Two-dimensional(2D)transition metal sulfides(TMDs)are emerging and highly well received 2D materials,which are considered as an ideal 2D platform for studying various electronic properties and potential applications due to their chemical diversity.Converting 2D TMDs into one-dimensional(1D)TMDs nanotubes can not only retain some advantages of 2D nanosheets but also providing a unique direction to explore the novel properties of TMDs materials in the 1D limit.However,the controllable preparation of high-quality nanotubes remains a major challenge.It is very necessary to review the advanced development of one-dimensional transition metal dichalcogenide nanotubes from preparation to application.Here,we first summarize a series of bottom-up synthesis methods of 1D TMDs,such as template growth and metal catalyzed method.Then,top-down synthesis methods are summarized,which included selfcuring and stacking of TMDs nanosheets.In addition,we discuss some key applications that utilize the properties of 1D-TMDs nanotubes in the areas of catalyst preparation,energy storage,and electronic devices.Last but not least,we prospect the preparation methods of high-quality 1D-TMDs nanotubes,which will lay a foundation for the synthesis of high-performance optoelectronic devices,catalysts,and energy storage components. 展开更多
关键词 one-dimensional transition metal sulfides NANOTUBES STRUCTURE Preparation method APPLICATIONS
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Determination of Kolmogorov Entropy of Chaotic Attractor Included in One-Dimensional Time Series of Meteorological Data
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作者 严绍瑾 彭永清 王建中 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第2期243-250,共8页
The 1970-1985 day to day averaged pressure dataset of Shanghai and the extension method in phase space are used to calculate the correlation dimension D and the second-order Renyi entropy K2 of the approximation of Ko... The 1970-1985 day to day averaged pressure dataset of Shanghai and the extension method in phase space are used to calculate the correlation dimension D and the second-order Renyi entropy K2 of the approximation of Kolmogorov's entropy, the fractional dimension D = 7.7-7.9 and the positive value K2 - 0.1 are obtained. This shows that the attractor for the short-term weather evolution in the monsoon region of China exhibits a chaotic motion. The estimate of K2 yields a predictable time scale of about ten days. This result is in agreement with that obtained earlier by the dynamic-statistical approach.The effects of the lag time i on the estimate of D and K2 are investigated. The results show that D and K2 are convergent with respect to i. The day to day averaged pressure series used in this paper are treated for the extensive phase space with T = 5, the coordinate components are independent of each other; therefore, the dynamical character quantities of the system are stable and reliable. 展开更多
关键词 Determination of Kolmogorov Entropy of Chaotic Attractor Included in one-dimensional Time Series of Meteorological data
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A tunable acoustic metasurface via one-dimensional mechanical adjustment for real-time focusing
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作者 Jie Hu Mengqi Jiang +1 位作者 Rui Zang Yuhang Qian 《Chinese Physics B》 2025年第10期399-404,共6页
Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we... Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we present a mechanically programmable acoustic metamaterial for real-time focal tuning via one-dimensional phase-gradient modulation in this paper.The device integrates a phase gradient structure with concave cavity channels and an x-shaped telescopic mechanical framework,enabling dynamic adjustment of inter-unit spacing(1 mm-3 mm)through a microcontroller-driven motor.By modulating the spacing between adjacent channels,the phase gradient is precisely controlled,allowing continuous focal shift from 50 mm to 300 mm along the x-axis at 7500 Hz.Broadband focusing is also discussed in the range6800 Hz-8100 Hz,with transmission coefficients exceeding 0.5,ensuring high efficiency and robust performance.Experimental results align closely with simulations,validating the design's effectiveness and adaptability.Unlike conventional programmable metamaterials requiring multi-dimensional parameter optimization,this approach simplifies real-time control through single-axis mechanical adjustment,significantly reducing operational complexity.Due to the advantages of broadband focusing,simple control mode,real-time monitoring,and so on,the device may have extensive applications in the fields of acoustic imaging,nondestructive testing,ultrasound medical treatment,etc. 展开更多
关键词 phase gradient structure one-dimensional mechanical adjustment adjustable focusing
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Rational Design of One-Dimensional Bifunctional PBA Nanocomposites as Efficient Electrocatalysts for Oxygen Evolution Reaction
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作者 Songtao Zhang Yihao Chen +6 位作者 Wenhui Hu Xudong Chen Ziming Qiu Yichun Su Rongmei Zhu Mingbo Zheng Huan Pang 《Transactions of Tianjin University》 2025年第2期179-188,共10页
The oxygen evolution reaction(OER),a critical half-reaction in water electrolysis,has garnered significant attention.However,sluggish OER kinetics has emerged as a major impediment to efficient electrochemical energy c... The oxygen evolution reaction(OER),a critical half-reaction in water electrolysis,has garnered significant attention.However,sluggish OER kinetics has emerged as a major impediment to efficient electrochemical energy conversion.There is an urgent need to design novel electrocatalysts with optimized OER kinetics and enhanced intrinsic activity to improve overall OER performance.Herein,one-dimensional(1D)nanocomposites with high electrocatalytic activity were developed through the deposition of CoFePBA nanocubes onto the surface of MnO_(2) nanowires.The electronic structure of the nanocomposite surface was modified,and the synergistic effects between transition metals were leveraged to enhance catalytic activity through the deposition of Prussian blue analog(PBA)nanocubes on manganese dioxide nanowires.Specifically,CoFePBA featured an open crystal structure that offiered numerous electrochemical active sites and efficient charge transfer pathways.Additionally,the synergistic interactions between Co and Fe significantly reduced the OER overpotential.Additionally,the 1D rigid MnO_(2) acted as protective armor,ensuring the stability of active sites within CoFePBA during the OER.The synthesized MnO_(2)@CoFePBA achieved an overpotential of 1.614 V at 10 mA/cm^(2) and a small Tafel slope of 94 mV/dec and demonstrated stable performance for over 200 h.This work offers new insights into the rational design of various PBA-based nanocomposites with high activity and stability. 展开更多
关键词 one-dimensional materials NANOCOMPOSITES Prussian blue analog(PBA) Synergistic effect ELECTROCATALYSTS
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Thermodynamics of classical one-dimensional generalized nonlinear Klein-Gordon lattice model
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作者 Hu-Wei Jia Ning-Hua Tong 《Chinese Physics B》 2025年第8期381-396,共16页
We study the thermodynamic properties of the classical one-dimensional generalized nonlinear Klein-Gordon lattice model(n≥2)by using the cluster variation method with linear response theory.The results of this method... We study the thermodynamic properties of the classical one-dimensional generalized nonlinear Klein-Gordon lattice model(n≥2)by using the cluster variation method with linear response theory.The results of this method are exact in the thermodynamic limit.We present the single-site reduced densityρ^((1))(z),averages such as(z^(2)),<|z^(n)|>,and<(z_(1)-z_(2))^(2)>,the specific heat C_(v),and the static correlation functions.We analyze the scaling behavior of these quantities and obtain the exact scaling powers at the low and high temperatures.Using these results,we gauge the accuracy of the projective truncation approximation for theφ^(4)lattice model. 展开更多
关键词 cluster variation method linear response theory one-dimensional generalized nonlinear Klein-Gordon lattice model
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Ultraprecision and highly uniform nanoscale conformality enabled by introducing oxide buffer layer for one-dimensional grating standard
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作者 Ya-Xin Zhang Song Wang +9 位作者 Chen-Ying Wang Yi-Fan Zhao Feng Han Di Liu Peng-Cheng Zhang Nan Zhu Kun Zheng Wei Ren Wei-Xuan Jing Zhuang-De Jiang 《Rare Metals》 2025年第7期4779-4788,共10页
One-dimensional nano-grating standard(ODNGS)is widely recognized as a crucial nanometric standard for metrological technology.However,achieving the ultratiny size of ODNGS with high consistent uniformity and low rough... One-dimensional nano-grating standard(ODNGS)is widely recognized as a crucial nanometric standard for metrological technology.However,achieving the ultratiny size of ODNGS with high consistent uniformity and low roughness by conventional processes such as the inductively coupled plasma(ICP)etching methodpresents a significant challenge in obtaining accurate calibration values.In this work,a 50-nm ODNGS with a conformal buffer layer(Al_(2)O_(3))is successfully obtained,indicating outstanding stability and abrasion resistance.Remarkably,the introduction of hydrogen silsesquioxane(HSQ)and amorphous Al_(2)O_(3)simultaneously guarantees an incredibly small expanded uncertainty(0.5 nm)and repeatability of the standard uniformity(less than 0.3 nm)in the grating dimensions.TheⅠ-Ⅴcurves of ODNGS with an Al_(2)O_(3)buffer layer at room temperature(RT)and200℃are depicted respectively to showcase the sustained favorable insulation properties.Notably,the nanostructure fluctuation,line edge roughness(LER)and line width roughness(LWR)of the standard can be decreased obviously by 64.1%,63%and 70%,respectively.Our results suggest that the ODNGS with Al_(2)O_(3)exhibits exceptional precision and robust calibration reliability for calibrating nanoscale measuring instruments.It holds tremendous potential for manufacturing high-precision nanostructures and grating arrays with precisely controllable dimensions,which will play a pivotal role in the fabrication of microfluidics chips,metasurface and photodetectors in the future. 展开更多
关键词 Nanoscale conformality Calibration one-dimensional grating standard Al_(2)O_(3)conformality
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Modulating electronic properties of carbon nanotube via constructing one-dimensional vdW heterostructures
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作者 Wenqi Lv Weili Li +1 位作者 Wei Ji Yanning Zhang 《Chinese Physics B》 2025年第6期512-516,共5页
Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is... Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is explored by filling CNTs with one-dimensional(1D)-TM_(6)Te_(6) nanowires to form TM_(6)Te_(6)@CNT-(16,0) 1D van der Waals heterostructures(1D-vd WHs). The systematic first-principles studies on the electronic properties of 1D-vd WHs show that N-type doping CNTs can be formed by charge transfer from TM_(6)Te_(6) nanowires to CNTs, without introducing additional carrier scattering.Particularly, contribution from both T M(e.g., Sc and Y) and Te atoms strengthens the charge transfer. The outside CNTs further confine the dispersion of Te-p orbitals in nanowires that deforms the C-π states at the bottom of the conduction band to quasi sp^(3) hybridization. Our study provides an inner doping strategy that can effectively confine the charge polarity of CNTs and further broaden its applications in some novel nano-devices. 展开更多
关键词 electronic modification of CNTs one-dimensional(1D)vdW heterostructures inner doping density functional theory
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Implementation of a One-Dimensional Enthalpy Sea-Ice Model in a Simple Pycnocline Prediction Model for Sea-Ice Data Assimilation Studies
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作者 Xinrong WU Shaoqing ZHANG Zhengyu LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第2期193-207,共15页
To further explore enthalpy-based sea-ice assimilation, a one-dimensional (1D) enthalpy sea-ice model is implemented into a simple pycnocline prediction model. The 1D enthalpy sea-ice model includes the physical pro... To further explore enthalpy-based sea-ice assimilation, a one-dimensional (1D) enthalpy sea-ice model is implemented into a simple pycnocline prediction model. The 1D enthalpy sea-ice model includes the physical processes such as brine expulsion, flushing, and salt diffusion. After being coupled with the atmosphere and ocean components, the enthalpy sea-ice model can be integrated stably and serves as an important modulator of model variability. Results from a twin experiment show that the sea-ice data assimilation in the enthalpy space can produce smaller root-mean-square errors of model variables than the traditional scheme that assimilates the observations of ice concentration, especially for slow-varying states. This study provides some insights into the improvement of sea-ice data assimilation in a coupled general circulation model. 展开更多
关键词 sea ice ENTHALPY coupled model data assimilation ensemble Kalman filter
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On the interfacial behavior of a one-dimensional hexagonal piezoelectric quasicrystal film based on the beam theory
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作者 Wenkai ZHANG C.S.LU +2 位作者 Minghao ZHAO Cuiying FAN Huayang DANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期289-304,共16页
In this paper,the mechanical response of a one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)thin film is analyzed under electric and temperature loads.Based on the Euler-Bernoulli beam theory,a theoretical ... In this paper,the mechanical response of a one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)thin film is analyzed under electric and temperature loads.Based on the Euler-Bernoulli beam theory,a theoretical model is proposed,resulting in coupled governing integral equations that account for interfacial normal and shear stresses.To numerically solve these integral equations,an expansion method using orthogonal Chebyshev polynomials is employed.The results provide insights into the interfacial stresses,axial force,as well as axial and vertical deformations of the PQC film.Additionally,fracture criteria,including stress intensity factors,mode angles,and the J-integral,are evaluated.The solution is compared with the membrane theory,neglecting the normal stress and bending deformation.Finally,the effects of stiffness and aspect ratio on the PQC film are thoroughly discussed.This study serves as a valuable guide for controlling the mechanical response and conducting safety assessments of PQC film systems. 展开更多
关键词 one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)film beam theory electric and temperature loads Chebyshev polynomial interfacial behavior
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Spatio-Temporal Earthquake Analysis via Data Warehousing for Big Data-Driven Decision Systems
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作者 Georgia Garani George Pramantiotis Francisco Javier Moreno Arboleda 《Computers, Materials & Continua》 2026年第3期1963-1988,共26页
Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from sei... Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from seismic networks,satellite observations,and geospatial repositories,creating the need for scalable infrastructures capable of integrating and analyzing such data to support intelligent decision-making.Data warehousing technologies provide a robust foundation for this purpose;however,existing earthquake-oriented data warehouses remain limited,often relying on simplified schemas,domain-specific analytics,or cataloguing efforts.This paper presents the design and implementation of a spatio-temporal data warehouse for seismic activity.The framework integrates spatial and temporal dimensions in a unified schema and introduces a novel array-based approach for managing many-to-many relationships between facts and dimensions without intermediate bridge tables.A comparative evaluation against a conventional bridge-table schema demonstrates that the array-based design improves fact-centric query performance,while the bridge-table schema remains advantageous for dimension-centric queries.To reconcile these trade-offs,a hybrid schema is proposed that retains both representations,ensuring balanced efficiency across heterogeneous workloads.The proposed framework demonstrates how spatio-temporal data warehousing can address schema complexity,improve query performance,and support multidimensional visualization.In doing so,it provides a foundation for integrating seismic analysis into broader big data-driven intelligent decision systems for disaster resilience,risk mitigation,and emergency management. 展开更多
关键词 data warehouse data analysis big data decision systems SEISMOLOGY data visualization
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Interfacial analysis of a penny-shaped one-dimensional hexagonal functionally graded piezoelectric quasicrystal film on a temperature-dependent substrate
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作者 Kai LUO Cuiying FAN +2 位作者 Minghao ZHAO CSLU Huayang DANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第12期2297-2316,共20页
In this paper,we investigate the interfacial behavior of a thin,penny-shaped,one-dimensional(1D)hexagonal functionally graded(FG)piezoelectric quasicrystal(PQC)film bonded on a temperature-dependent elastic substrate ... In this paper,we investigate the interfacial behavior of a thin,penny-shaped,one-dimensional(1D)hexagonal functionally graded(FG)piezoelectric quasicrystal(PQC)film bonded on a temperature-dependent elastic substrate under thermal and electrical loads.The problem is modeled as axisymmetric based on the membrane theory,with the peeling stress and bending moment being disregarded.A potential theory method,combined with the Hankel transform technique,is utilized to derive the displacement field on the substrate surface.With perfect interfacial bonding assumption,an integral equation governing the phonon interfacial shear stress is formulated and numerically solved by the Chebyshev polynomials.Explicit expressions are derived for the interfacial shear stress,the internal stresses within the PQC film and the substrate,the axial strain,and the stress intensity factors(SIFs).Numerical simulations are conducted to investigate the effects of the film's aspect ratio,material inhomogeneity,material mismatch,and temperature-dependent material properties on its mechanical response.The results provide insights for the functional design and reliability assessment of FG PQC film/substrate systems. 展开更多
关键词 one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)film functionally graded(FG)material three-dimensional(3D)interfacial behavior stress intensity factor(SIF) temperature-dependent material property
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Real-world data and evidence:pioneering frontiers in precision oncology
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作者 Jingxin JIANG Weiwei PAN +4 位作者 Liyang SUN Liwei PANG Hailang CHEN Jian HUANG Wuzhen CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2026年第1期44-57,共14页
Real-world studies(RWSs)have emerged as a transformative force in oncology research,complementing traditional randomized controlled trials(RCTs)by providing comprehensive insights into cancer care within routine clini... Real-world studies(RWSs)have emerged as a transformative force in oncology research,complementing traditional randomized controlled trials(RCTs)by providing comprehensive insights into cancer care within routine clinical settings.This review examines the evolving landscape of RWSs in oncology,focusing on their implementation,methodological considerations,and impact on precision medicine.We systematically analyze how RWSs leverage diverse data sources,including electronic health records(EHRs),insurance claims,and patient registries,to generate evidence that bridges the gap between controlled clinical trials and real-world clinical practice.The review underscores the key contributions of RWSs,including capturing therapeutic outcomes in traditionally underrepresented populations,expanding drug indications,and evaluating long-term safety and effectiveness in routine clinical settings.While acknowledging significant challenges,including data quality variability and privacy concerns,we discuss how emerging technologies like artificial intelligence are helping to address these limitations.The integration of RWSs with traditional clinical research is revolutionizing the paradigm of precision oncology and enabling more personalized treatment approaches based on real-world evidence. 展开更多
关键词 Real-world study(RWS) Precision oncology Real-world data(RWD) Study design data characterization
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Combining different climate datasets better reflects the response of warm-temperate forests to climate:a case study from Mt.Dongling,Beijing
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作者 Shengjie Wang Haiyang Liu +1 位作者 Shuai Yuan Chenxi Xu 《Journal of Forestry Research》 2026年第2期131-143,共13页
Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and... Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology.This study evaluated the consistency between alternative climate datasets(including station and gridded data)and actual climate data(fixed-point observations near the sampling sites),in northeastern China’s warm temperate zone and analyzed differences in their correlations with tree-ring width index.The results were:(1)Gridded temperature data,as well as precipitation and relative humidity data from the Huailai meteorological station,was more consistent with the actual climate data;in contrast,gridded soil moisture content data showed significant discrepancies.(2)Horizontal distance had a greater impact on the representativeness of actual climate conditions than vertical elevation differences.(3)Differences in consistency between alternative and actual climate data also affected their correlations with tree-ring width indices.In some growing season months,correlation coefficients,both in magnitude and sign,differed significantly from those based on actual data.The selection of different alternative climate datasets can lead to biased results in assessing forest responses to climate change,which is detrimental to the management of forest ecosystems in harsh environments.Therefore,the scientific and rational selection of alternative climate data is essential for dendroecological and climatological research. 展开更多
关键词 Climate data representativeness Alternative climate data selection Response differences Deciduous broad-leaf forest Warm temperate zone
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Photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer
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作者 Jialin Li Tingting Li +2 位作者 Yiming Ma Yi Shen Mingjian Sun 《Journal of Innovative Optical Health Sciences》 2026年第1期110-125,共16页
Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.Howev... Photoacoustic-computed tomography is a novel imaging technique that combines high absorption contrast and deep tissue penetration capability,enabling comprehensive three-dimensional imaging of biological targets.However,the increasing demand for higher resolution and real-time imaging results in significant data volume,limiting data storage,transmission and processing efficiency of system.Therefore,there is an urgent need for an effective method to compress the raw data without compromising image quality.This paper presents a photoacoustic-computed tomography 3D data compression method and system based on Wavelet-Transformer.This method is based on the cooperative compression framework that integrates wavelet hard coding with deep learning-based soft decoding.It combines the multiscale analysis capability of wavelet transforms with the global feature modeling advantage of Transformers,achieving high-quality data compression and reconstruction.Experimental results using k-wave simulation suggest that the proposed compression system has advantages under extreme compression conditions,achieving a raw data compression ratio of up to 1:40.Furthermore,three-dimensional data compression experiment using in vivo mouse demonstrated that the maximum peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)values of reconstructed images reached 38.60 and 0.9583,effectively overcoming detail loss and artifacts introduced by raw data compression.All the results suggest that the proposed system can significantly reduce storage requirements and hardware cost,enhancing computational efficiency and image quality.These advantages support the development of photoacoustic-computed tomography toward higher efficiency,real-time performance and intelligent functionality. 展开更多
关键词 Photoacoustic-computed tomography data compression TRANSFORMER
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Toward Secure and Auditable Data Sharing:A Cross-Chain CP-ABE Framework
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作者 Ye Tian Zhuokun Fan Yifeng Zhang 《Computers, Materials & Continua》 2026年第4期1509-1529,共21页
Amid the increasing demand for data sharing,the need for flexible,secure,and auditable access control mechanisms has garnered significant attention in the academic community.However,blockchain-based ciphertextpolicy a... Amid the increasing demand for data sharing,the need for flexible,secure,and auditable access control mechanisms has garnered significant attention in the academic community.However,blockchain-based ciphertextpolicy attribute-based encryption(CP-ABE)schemes still face cumbersome ciphertext re-encryption and insufficient oversight when handling dynamic attribute changes and cross-chain collaboration.To address these issues,we propose a dynamic permission attribute-encryption scheme for multi-chain collaboration.This scheme incorporates a multiauthority architecture for distributed attribute management and integrates an attribute revocation and granting mechanism that eliminates the need for ciphertext re-encryption,effectively reducing both computational and communication overhead.It leverages the InterPlanetary File System(IPFS)for off-chain data storage and constructs a cross-chain regulatory framework—comprising a Hyperledger Fabric business chain and a FISCO BCOS regulatory chain—to record changes in decryption privileges and access behaviors in an auditable manner.Security analysis shows selective indistinguishability under chosen-plaintext attack(sIND-CPA)security under the decisional q-Parallel Bilinear Diffie-Hellman Exponent Assumption(q-PBDHE).In the performance and experimental evaluations,we compared the proposed scheme with several advanced schemes.The results show that,while preserving security,the proposed scheme achieves higher encryption/decryption efficiency and lower storage overhead for ciphertexts and keys. 展开更多
关键词 data sharing blockchain attribute-based encryption dynamic permissions
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Design,Realization,and Evaluation of Faster End-to-End Data Transmission over Voice Channels
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作者 Jian Huang Ming weiLi +2 位作者 Yulong Tian Yi Yao Hao Han 《Computers, Materials & Continua》 2026年第4期1650-1675,共26页
With the popularization of new technologies,telephone fraud has become the main means of stealing money and personal identity information.Taking inspiration from the website authentication mechanism,we propose an end-... With the popularization of new technologies,telephone fraud has become the main means of stealing money and personal identity information.Taking inspiration from the website authentication mechanism,we propose an end-to-end datamodem scheme that transmits the caller’s digital certificates through a voice channel for the recipient to verify the caller’s identity.Encoding useful information through voice channels is very difficult without the assistance of telecommunications providers.For example,speech activity detection may quickly classify encoded signals as nonspeech signals and reject input waveforms.To address this issue,we propose a novel modulation method based on linear frequency modulation that encodes 3 bits per symbol by varying its frequency,shape,and phase,alongside a lightweightMobileNetV3-Small-based demodulator for efficient and accurate signal decoding on resource-constrained devices.This method leverages the unique characteristics of linear frequency modulation signals,making them more easily transmitted and decoded in speech channels.To ensure reliable data delivery over unstable voice links,we further introduce a robust framing scheme with delimiter-based synchronization,a sample-level position remedying algorithm,and a feedback-driven retransmission mechanism.We have validated the feasibility and performance of our system through expanded real-world evaluations,demonstrating that it outperforms existing advanced methods in terms of robustness and data transfer rate.This technology establishes the foundational infrastructure for reliable certificate delivery over voice channels,which is crucial for achieving strong caller authentication and preventing telephone fraud at its root cause. 展开更多
关键词 Deep learning modulation CHIRP data over voice
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A Composite Loss-Based Autoencoder for Accurate and Scalable Missing Data Imputation
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作者 Thierry Mugenzi Cahit Perkgoz 《Computers, Materials & Continua》 2026年第1期1985-2005,共21页
Missing data presents a crucial challenge in data analysis,especially in high-dimensional datasets,where missing data often leads to biased conclusions and degraded model performance.In this study,we present a novel a... Missing data presents a crucial challenge in data analysis,especially in high-dimensional datasets,where missing data often leads to biased conclusions and degraded model performance.In this study,we present a novel autoencoder-based imputation framework that integrates a composite loss function to enhance robustness and precision.The proposed loss combines(i)a guided,masked mean squared error focusing on missing entries;(ii)a noise-aware regularization term to improve resilience against data corruption;and(iii)a variance penalty to encourage expressive yet stable reconstructions.We evaluate the proposed model across four missingness mechanisms,such as Missing Completely at Random,Missing at Random,Missing Not at Random,and Missing Not at Random with quantile censorship,under systematically varied feature counts,sample sizes,and missingness ratios ranging from 5%to 60%.Four publicly available real-world datasets(Stroke Prediction,Pima Indians Diabetes,Cardiovascular Disease,and Framingham Heart Study)were used,and the obtained results show that our proposed model consistently outperforms baseline methods,including traditional and deep learning-based techniques.An ablation study reveals the additive value of each component in the loss function.Additionally,we assessed the downstream utility of imputed data through classification tasks,where datasets imputed by the proposed method yielded the highest receiver operating characteristic area under the curve scores across all scenarios.The model demonstrates strong scalability and robustness,improving performance with larger datasets and higher feature counts.These results underscore the capacity of the proposed method to produce not only numerically accurate but also semantically useful imputations,making it a promising solution for robust data recovery in clinical applications. 展开更多
关键词 Missing data imputation autoencoder deep learning missing mechanisms
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