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Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
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作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin d deficiency
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Enabling Intrinsic Antiferroelectricity in Two-dimensional NbOCl_(2):Molecular Dynamics Simulations based on Deep Learning Interatomic Potential
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作者 Jiawei Mao Yinglu Jia +2 位作者 Gaoyang Gou Shi Liu Xiao Cheng Zeng 《Chinese Physics Letters》 2026年第1期156-178,共23页
Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely orien... Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely oriented.Using NbOCl_(2) monolayer with competing ferroelectric(FE)and antiferroelectric(AFE)phases as a 2D material platform,we demonstrate the emergence of intrinsic antiferroelectricity in NbOCl_(2) monolayer under experimentally accessible shear strain,along with new functionality associated with electric field-induced AFE-to-FE phase transition.Specifically,the complex configuration space accommodating FE and AFE phases,polarization switching kinetics,and finite temperature thermodynamic properties of 2D NbOCl_(2) are all accurately predicted by large-scale molecular dynamics simulations based on deep learning interatomic potential model.Moreover,room temperature stable antiferroelectricity with low polarization switching barrier and one-dimensional collinear polarization arrangement is predicted in shear-deformed NbOCl_(2) monolayer.The transition from AFE to FE phase in 2D NbOCl_(2) can be triggered by a low critical electric field,leading to a double polarization–electric(P–E)loop with small hysteresis.A new type of optoelectronic device composed of AFE-NbOCl_(2) is proposed,enabling electric“writing”and nonlinear optical“reading”logical operation with fast operation speed and low power consumption. 展开更多
关键词 d monolayers local dipoles nonequivalent sublattices intrinsic antiferroelectricity two dimensional nbocl d antiferroelectricity experimentally accessible shear strainalong molecular dynamics simulations
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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3d culture model drug screening
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DRL-Based Cross-Regional Computation Offloading Algorithm
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作者 Lincong Zhang Yuqing Liu +2 位作者 Kefeng Wei Weinan Zhao Bo Qian 《Computers, Materials & Continua》 2026年第1期901-918,共18页
In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network e... In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network environments where rapid response is mandatory for safety-critical applications.In scenarios where edge servers are sparsely deployed,the lack of coordination and information sharing often leads to load imbalance,thereby increasing system latency.Furthermore,in regions without edge server coverage,tasks must be processed locally,which further exacerbates latency issues.To address these challenges,we propose a novel and efficient Deep Reinforcement Learning(DRL)-based approach aimed at minimizing average task latency.The proposed method incorporates three offloading strategies:local computation,direct offloading to the edge server in local region,and device-to-device(D2D)-assisted offloading to edge servers in other regions.We formulate the task offloading process as a complex latency minimization optimization problem.To solve it,we propose an advanced algorithm based on the Dueling Double Deep Q-Network(D3QN)architecture and incorporating the Prioritized Experience Replay(PER)mechanism.Experimental results demonstrate that,compared with existing offloading algorithms,the proposed method significantly reduces average task latency,enhances user experience,and offers an effective strategy for latency optimization in future edge computing systems under dynamic workloads. 展开更多
关键词 Edge computing computational task offloading deep reinforcement learning d3QN device-to-device communication system latency optimization
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Differentiating the 2D Passivation from Amorphous Passivation in Perovskite Solar Cells
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作者 Xiaojian Zheng Shehzad Ahmed +12 位作者 Yu Zhang Guoqiang Xu Junyu Wang Di Lu Tingshu Shi Jun Tang Lei Yan Wei Chen Peigang Han Zhixin Liu Danish Khan Xingzhu Wang Zeguo Tang 《Nano-Micro Letters》 2026年第2期631-643,共13页
The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spac... The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spacer cation and the quality of the 2D capping layer are critical factors in achieving the required results.In this study,we compared two fluorinated salts:4-(trifluoromethyl)benzamidine hydrochloride(4TF-BA·HCl)and 4-fluorobenzamidine hydrochloride(4F-BA·HCl)to engineer the 3D/2D perovskite films.Surprisingly,4F-BA formed a high-performance 3D/2D heterojunction,while4TF-BA produced an amorphous layer on the perovskite films.Our findings indicate that the balanced intramolecular charge polarization,which leads to effective hydrogen bonding,is more favorable in 4F-BA than in 4TF-BA,promoting the formation of a crystalline 2D perovskite.Nevertheless,4TF-BA managed to improve efficiency to 24%,surpassing the control device,primarily due to the natural passivation capabilities of benzamidine.Interestingly,the devices based on 4F-BA demonstrated an efficiency exceeding 25%with greater longevity under various storage conditions compared to 4TF-BA-based and the control devices. 展开更多
关键词 3d/2d perovskite films Benzamidine Amorphous passivation 2d passivation Inverted perovskite solar cells
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Beyond the Silicon Plateau:A Convergence of Novel Materials for Transistor Evolution
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作者 Jung Hun Lee Jae Young Kim +3 位作者 Hyeon-Ji Lee Sung-Jin Choi Yoon Jung Lee Ho Won Jang 《Nano-Micro Letters》 2026年第2期786-844,共59页
As silicon-based transistors face fundamental scaling limits,the search for breakthrough alternatives has led to innovations in 3D architectures,heterogeneous integration,and sub-3 nm semiconductor body thicknesses.Ho... As silicon-based transistors face fundamental scaling limits,the search for breakthrough alternatives has led to innovations in 3D architectures,heterogeneous integration,and sub-3 nm semiconductor body thicknesses.However,the true effectiveness of these advancements lies in the seamless integration of alternative semiconductors tailored for next-generation transistors.In this review,we highlight key advances that enhance both scalability and switching performance by leveraging emerging semiconductor materials.Among the most promising candidates are 2D van der Waals semiconductors,Mott insulators,and amorphous oxide semiconductors,which offer not only unique electrical properties but also low-power operation and high carrier mobility.Additionally,we explore the synergistic interactions between these novel semiconductors and advanced gate dielectrics,including high-K materials,ferroelectrics,and atomically thin hexagonal boron nitride layers.Beyond introducing these novel material configurations,we address critical challenges such as leakage current and long-term device reliability,which become increasingly crucial as transistors scale down to atomic dimensions.Through concrete examples showcasing the potential of these materials in transistors,we provide key insights into overcoming fundamental obstacles—such as device reliability,scaling down limitations,and extended applications in artificial intelligence—ultimately paving the way for the development of future transistor technologies. 展开更多
关键词 Modern transistors Transistor scaling Alternative semiconductors 3d integration device reliability
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Interfacial Superconductivity in the Type-Ⅲ Heterostructure SnSe_(2)/PtTe_(2)
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作者 Jun Fan Xiao-Le Qiu +2 位作者 Ben-Chao Gong Kai Liu Zhong-Yi Lu 《Chinese Physics Letters》 2026年第1期248-264,共17页
Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems cons... Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification. 展开更多
关键词 d heterostructure condensed matter type III heterostructure PtTe interfacial superconductivity SnSe electron dopingwe first principles calculations
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拉萨市不同孕期妇女血清25羟基维生素D水平的比较
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作者 尼玛顿珠 扎西央宗 +5 位作者 边珍 益西措姆 支张卓玛 詹明君 巴桑央吉 秦绪珍 《基础医学与临床》 2026年第1期120-123,共4页
目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期... 目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期体检妇女为正常对照组,采用雅培i2000化学发光仪检测血清25-(OH)D水平,用SPSS统计学软件进行统计分析。结果367例孕期妇女血清25-(OH)D总体水平为11.5(8.5,17.3)ng/mL。VD充足、不足、缺乏分别占16.6%、30.0%、53.4%;209例健康对照组妇女血清25-(OH)D总体水平为9.9(7.7,13.6)ng/mL。VD充足、不足、缺乏分别占6.7%、27.8%、65.5%。9~13^(+6)周、15~20^(+6)周孕期妇女血清25-(OH)D水平比较差异无统计学意义。结论拉萨市孕期和未妊娠育龄妇女普遍存在VD不足或缺乏现象,应在备孕及怀孕期间补充VD。 展开更多
关键词 孕妇 25羟基维生素d 维生素d
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine d3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMOdULATION Parkinson’s disease primary motor cortex
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Hybrid Framework for Structural Analysis: Integrating Topology Optimization, Adjacent Element Temperature-Driven Pre-Stress, and Greedy Algorithms
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作者 Ibrahim T.Teke Ahmet H.Ertas 《Computers, Materials & Continua》 2025年第7期243-264,共22页
This study presents a novel hybrid topology optimization and mold design framework that integrates process fitting,runner system optimization,and structural analysis to significantly enhance the performance of injecti... This study presents a novel hybrid topology optimization and mold design framework that integrates process fitting,runner system optimization,and structural analysis to significantly enhance the performance of injection-molded parts.At its core,the framework employs a greedy algorithm that generates runner systems based on adjacency and shortest path principles,leading to improvements in both mechanical strength and material efficiency.The design optimization is validated through a series of rigorous experimental tests,including three-point bending and torsion tests performed on key-socket frames,ensuring that the optimized designs meet practical performance requirements.A critical innovation of the framework is the development of the Adjacent Element Temperature-Driven Prestress Algorithm(AETDPA),which refines the prediction of mechanical failure and strength fitting.This algorithm has been shown to deliver mesh-independent accuracy,thereby enhancing the reliability of simulation results across various design iterations.The framework’s adaptability is further demonstrated by its ability to adjust optimization methods based on the unique geometry of each part,thus accelerating the overall design process while ensuring struc-tural integrity.In addition to its immediate applications in injection molding,the study explores the potential extension of this framework to metal additive manufacturing,opening new avenues for its use in advanced manufacturing technologies.Numerical simulations,including finite element analysis,support the experimental findings and confirm that the optimized designs provide a balanced combination of strength,durability,and efficiency.Furthermore,the integration challenges with existing injection molding practices are addressed,underscoring the framework’s scalability and industrial relevance.Overall,this hybrid topology optimization framework offers a computationally efficient and robust solution for advanced manufacturing applications,promising significant improvements in design efficiency,cost-effectiveness,and product performance.Future work will focus on further enhancing algorithm robustness and exploring additional applications across diverse manufacturing processes. 展开更多
关键词 Plastic injection molding 3d printing three-point bending tensile test adjacent element temperature-driven pre-stress algorithm d-S-ER S-d-S-ER thermal expansion greedy algorithm
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Motion In-Betweening via Frequency-Domain Diffusion Model
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作者 Qiang Zhang Shuo Feng +2 位作者 Shanxiong Chen Teng Wan Ying Qi 《Computers, Materials & Continua》 2026年第1期275-296,共22页
Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frame... Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frames remains a fundamental yet unresolved challenge.Existing methods typically rely on dense keyframe inputs or complex prior structures,making it difficult to balance motion quality and plausibility under conditions such as sparse constraints,long-term dependencies,and diverse motion styles.To address this,we propose a motion generation framework based on a frequency-domain diffusion model,which aims to better model complex motion distributions and enhance generation stability under sparse conditions.Our method maps motion sequences to the frequency domain via the Discrete Cosine Transform(DCT),enabling more effective modeling of low-frequency motion structures while suppressing high-frequency noise.A denoising network based on self-attention is introduced to capture long-range temporal dependencies and improve global structural awareness.Additionally,a multi-objective loss function is employed to jointly optimize motion smoothness,pose diversity,and anatomical consistency,enhancing the realism and physical plausibility of the generated sequences.Comparative experiments on the Human3.6M and LaFAN1 datasets demonstrate that our method outperforms state-of-the-art approaches across multiple performance metrics,showing stronger capabilities in generating intermediate motion frames.This research offers a new perspective and methodology for human motion generation and holds promise for applications in character animation,game development,and virtual interaction. 展开更多
关键词 Motion generation diffusion model frequency domain human motion synthesis self-attention network 3d motion interpolation
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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3d macroporous carbon-based foams directional pore channels Salting-out protein assemblies EM wave absorption directional dependence
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Hierarchical Event-Triggered Predictive Control for Cross-Domain Unmanned Systems With Mixed Constraints
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作者 Ming-Feng Ge Yi-Fan Li +3 位作者 Chen-Bin Wu Zhi-Wei Liu Yan Jia Si-Sheng Liu 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1938-1940,共3页
Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmann... Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmanned surface vehicles(USVs).We assume that each agent suffers from by the mixed constraints on its velocity,control input and Euler angle.Solving the MDFT problem implies that 1)The virtual state of each USV is determined in the earth coordinate by expanding its 2D work space to the 3D space. 展开更多
关键词 expanding its d work space mixed constraints unmanned aerial vehicles interconnected agentsnamelyunmanned aerial vehicles uavs multi dimension formation tracking hierarchical event triggered predictive control unmanned surface vehicles usvs we virtual state
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Design optimization and FEA of B-6 and B-7 levels ballistics armor:A modelling approach
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作者 Muhammad Naveed CHU Jinkui +1 位作者 Atif Ur Rehman Arsalan Hyder 《大连理工大学学报》 北大核心 2026年第1期66-77,共12页
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl... Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor. 展开更多
关键词 radiator armor ballistics simulation Johnson-Cook model armor-piercing projectile perforated d-shaped armor plate
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基于轻量化模型的无人机6D位姿估计
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作者 肖欣招 郑玉恒 +1 位作者 赛庆毅 付东翔 《控制工程》 北大核心 2026年第1期80-91,共12页
为了提高无人机位姿估计性能,对YOLO6D进行改进,提出了无人机六维(six-dimensional,6D)位姿估计算法CASlim_YOLO6D。CASlim_YOLO6D模型在主干特征提取部分采用GBneck_1模块,减少了3×3卷积产生的特征冗余,在特征融合部分通过深度可... 为了提高无人机位姿估计性能,对YOLO6D进行改进,提出了无人机六维(six-dimensional,6D)位姿估计算法CASlim_YOLO6D。CASlim_YOLO6D模型在主干特征提取部分采用GBneck_1模块,减少了3×3卷积产生的特征冗余,在特征融合部分通过深度可分离卷积压缩模型的参数量和计算量,并引入卷积块注意力模块(convolutional block attention module,CBAM)改善参数量和计算量压缩导致的位姿估计精度下降。与YOLO6D模型的对比实验结果表明,CASlim_YOLO6D模型在满足位姿估计精度的同时,提高了检测速度,满足位姿估计的实时性。实验搭建了视觉引导的机械臂系统,并利用该系统和CASlim_YOLO6D抓取共轴双旋翼无人机,实验结果验证了该算法的可行性和有效性。 展开更多
关键词 6d位姿估计 无人机 YOLO6d 轻量化
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基于定向进化的D-阿洛酮糖3-差向异构酶分子改造
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作者 孙明静 刘展志 +3 位作者 刘姝含 王留欣 王胜 吴敬 《食品与发酵工业》 北大核心 2026年第1期25-30,共6页
随着生活质量的提升,人们对健康的要求也日益增高,代糖逐渐走入人们的视野。D-阿洛酮糖是一种低热量高甜度的稀少糖,是一种理想的蔗糖替代品。工业制备D-阿洛酮糖的工具酶主要为D-阿洛酮糖3-差向异构酶(D-allulose 3-epimerase,DAE),然... 随着生活质量的提升,人们对健康的要求也日益增高,代糖逐渐走入人们的视野。D-阿洛酮糖是一种低热量高甜度的稀少糖,是一种理想的蔗糖替代品。工业制备D-阿洛酮糖的工具酶主要为D-阿洛酮糖3-差向异构酶(D-allulose 3-epimerase,DAE),然而要应对工业生产需求,DAE的比活力仍需进一步提升。该研究利用转录因子PsiR构成的D-阿洛酮糖特异型生物传感器,结合荧光激活细胞分选和96孔微孔板筛选,最终获得了比活力提高26.21%的Clostridium cellulolyticum H10来源的DAE(CcDAE)突变体F147L,其最适温度为60℃,最适pH为7.5。该研究不仅成功证明转录因子型生物传感器在蛋白酶定向进化中具有相当高的应用价值,也为DAE的改造提供了新的思路。 展开更多
关键词 d-阿洛酮糖 d-阿洛酮糖3-差向异构酶 定向进化 生物传感器
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个性化3D打印导板引导下胸腰椎手术皮质骨轨迹螺钉置入准确性
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作者 朱寅 王黎明 +4 位作者 沙卫平 宋锦程 林小龙 曹泽 盛晓磊 《中国组织工程研究》 北大核心 2026年第15期3862-3870,共9页
背景:与传统椎弓根螺钉相比,皮质骨轨迹螺钉通道全程均为皮质骨,具有更牢靠的生物力学优势,然而安全、准确地置入皮质骨轨迹螺钉对脊柱外科医师技术要求较高。理论上在3D打印个性化导板引导下能有效提高一次性置钉的准确度、简化置钉操... 背景:与传统椎弓根螺钉相比,皮质骨轨迹螺钉通道全程均为皮质骨,具有更牢靠的生物力学优势,然而安全、准确地置入皮质骨轨迹螺钉对脊柱外科医师技术要求较高。理论上在3D打印个性化导板引导下能有效提高一次性置钉的准确度、简化置钉操作、提高手术效率,但目前国内外相关报道较少。目的:探讨应用个性化3D打印导板辅助皮质骨轨迹螺钉置入治疗合并骨质疏松胸腰椎骨折的准确性与安全性。方法:选择2020年1月至2024年1月行皮质骨轨迹螺钉内固定的58例合并骨质疏松的胸腰椎(T_(11)-L_(4))骨折患者,共置入348枚螺钉。根据置钉方案分为2组,3D导板组30例行个性化3D打印导板辅助置钉,共置入螺钉180枚;对照组28例行徒手方式置钉,共计置入螺钉168枚。通过比较两组间手术相关指标、置钉情况、伤椎的复位与脊柱后凸畸形矫正情况以及术后疗效等,评估不同置钉方案的效果和适用性。结果与结论:①3D导板组在切口长度、手术时间、置钉时间、术中透视次数、术中出血量、术后引流量以及住院天数方面均显著优于对照组(P<0.05),但是两组的总费用相比差异无显著性意义(P>0.05);②3D导板组的置钉准确率高于对照组,螺钉对上关节突的侵犯率低于对照组,差异有显著性意义(P<0.05);③术后评估结果显示,两组在伤椎前缘高度百分比、Cobb角、目测类比评分以及Oswestry功能障碍指数方面均较术前有所改善,且差异有显著性意义(P<0.05);组间相比,3D导板组的Oswestry功能障碍指数更低,显示出更佳的胸腰椎功能(P<0.05),而在术后伤椎前缘高度百分比、Cobb角及目测类比评分方面,两组之间无显著性差异(P>0.05);④在围术期及随访期间,两组患者均未出现并发症;⑤提示个性化3D打印导板辅助皮质骨轨迹螺钉置入治疗合并骨质疏松的胸腰椎骨折是一种可行的方式,具有微创、高效、精准及安全等优势,可获得满意的临床效果。 展开更多
关键词 胸腰椎骨折 骨质疏松 皮质骨轨迹螺钉 内固定 3d打印导板 置钉准确性
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具有修正的Min(N,D)-策略和单重休假的Geo/G/1离散时间排队分析
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作者 魏瑛源 余玅妙 唐玉玲 《应用数学》 北大核心 2026年第1期108-128,共21页
本文研究服务员具有单重休假和系统采用修正的Min(N,D)-策略的离散时间Geo/G/1排队系统,运用更新过程理论、全概率分解技术和z-变换工具,从任意初始状态开始,研究队长的瞬时性态和平稳性态,得到了任意时刻n^(+)处队长瞬态分布的z-变换... 本文研究服务员具有单重休假和系统采用修正的Min(N,D)-策略的离散时间Geo/G/1排队系统,运用更新过程理论、全概率分解技术和z-变换工具,从任意初始状态开始,研究队长的瞬时性态和平稳性态,得到了任意时刻n^(+)处队长瞬态分布的z-变换表达式和稳态分布的递推表达式,同时给出了不同时刻n^(-)、n、n^(+)和外部观测点处队长稳态分布之间的重要关系.进一步借助于数值实例,讨论了系统的空闲率与稳态平均队长关于系统参数的敏感性,并且阐述了便于作数值计算的队长稳态分布的递推公式在系统容量优化设计中的重要价值.最后,运用更新报酬过程定理,建立了费用结构模型,获得了系统长期运行下单位时间内所产生的期望费用的显示表达式,并通过数值算例,寻求使期望费用最小的最优控制策略(N^(*),D^(*)). 展开更多
关键词 离散时间排队 修正的Min(N d)-策略 单重休假 队长分布 系统容量优化设计 最优控制策略
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角度控制椎弓根螺钉置入工具结合3D模型及导板辅助置钉的精准度
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作者 杨镇源 张继伟 +3 位作者 张凯东 马冰清 张彦军 李军杰 《中国组织工程研究》 北大核心 2026年第15期3906-3912,共7页
背景:椎弓根螺钉目前广泛应用于脊柱外科临床,其精准置入为关注焦点。此次研究探寻了一种新的椎弓根螺钉置入方法,以期提高临床置钉的准确率。目的:观察应用自主研制的角度控制椎弓根螺钉置入工具结合3D模型及导板在辅助椎弓根螺钉置入... 背景:椎弓根螺钉目前广泛应用于脊柱外科临床,其精准置入为关注焦点。此次研究探寻了一种新的椎弓根螺钉置入方法,以期提高临床置钉的准确率。目的:观察应用自主研制的角度控制椎弓根螺钉置入工具结合3D模型及导板在辅助椎弓根螺钉置入中的应用价值。方法:选择2023年3月至2024年6月接受椎弓根螺钉内固定治疗的患者共计96例,随机分成2组,辅助组和徒手组各48例。辅助组使用角度控制椎弓根螺钉置入工具配合3D模型和导板辅助螺钉置入,徒手组则依赖C型臂X射线机进行定位,徒手置入螺钉。所有患者均进行CT检查以评估两种方式下单枚螺钉置入时间及精确度,另外对比C型臂X射线机使用频率。结果与结论:①辅助组共置入286枚螺钉,置钉用时(2.51±1.26)min/枚,精确置入成功率达到95.8%,C型臂透视次数为(1.45±2.12)次/枚;徒手组共置入螺钉264枚,置入用时为(3.27±1.54)min/枚,精确置入成功率为87.2%,C型臂透视次数是(2.19±1.73)次/枚;②相较而言,辅助组在这3个指标上均表现出显著优势:单枚螺钉置入时间更短,置钉准确率更高,且C型臂透视次数也相对较低,与徒手组相比差异有显著性意义(P<0.05);③提示在实施脊柱椎弓根钉置入时,利用角度控制的椎弓根螺钉置入工具配合3D模型和导板能有效提升置钉的精确度,降低所需时间,并且减少辐射暴露的风险,这无疑具备极高的临床实用意义。 展开更多
关键词 椎弓根螺钉 内固定 角度控制 3d模型 导板 置钉
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