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A Comprehensive Literature Review of AI-Driven Application Mapping and Scheduling Techniques for Network-on-Chip Systems
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作者 Naveed Ahmad Muhammad Kaleem +5 位作者 Mourad Elloumi Muhammad Azhar Mushtaq Ahlem Fatnassi Mohd Fazil Anas Bilal Abdulbasit A.Darem 《Computer Modeling in Engineering & Sciences》 2026年第1期118-155,共38页
Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance ... Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks. 展开更多
关键词 Application mapping mapping techniques netWORK-ON-CHIP system on chip optimisation
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Elastic properties of Cu–6wt% Ag alloy wires for pulsed magnets investigated by ultrasonic techniques 被引量:1
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作者 Ziyu Li Tianyi Gu +12 位作者 Wenqi Wei Yang Yuan Zhuo Wang Kangjian Luo Yupeng Pan Jianfeng Xie Shaozhe Zhang Tao Peng Lin Liu Qi Chen Xiaotao Han Yongkang Luo Liang Li 《Chinese Physics B》 2025年第2期90-95,共6页
Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit(~ 100 T) of pulsed magnets. Here, we... Conductor materials with good mechanical performance as well as high electrical and thermal conductivities are particularly important to break through the current bottle-neck limit(~ 100 T) of pulsed magnets. Here, we perform systematic studies on the elastic properties of the Cu–6wt% Ag alloy wire, which is a promising candidate material for the new-generation pulsed magnets, by employing two independent ultrasonic techniques, i.e., resonant ultrasound spectroscopy(RUS) and ultrasound pulse-echo experiments. Our RUS measurements manifest that the elastic properties of the Cu–6wt% Ag alloy wires can be improved by an electroplastic drawing procedure as compared with the conventional cold drawing. We also take this opportunity to test the availability of our newly-built ultrasound pulse-echo facility at the Wuhan National High Magnetic Field Center(WHMFC, China), and the results suggest that the elastic performance of the electroplastically-drawn Cu–6wt% Ag alloy wire remains excellent without anomalous softening under extreme conditions,e.g., in ultra-high magnetic field up to 50 T and nitrogen or helium cryogenic liquids. 展开更多
关键词 high-field magnet Cu–Ag alloy ultrasonic techniques elastic constants
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Corrigendum to“Elastic properties of Cu–6wt%Ag alloy wires for pulsed magnets investigated by ultrasonic techniques”
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作者 Ziyu Li Tianyi Gu +12 位作者 Wenqi Wei Yang Yuan Zhuo Wang Kangjian Luo Yupeng Pan Jianfeng Xie Shaozhe Zhang Tao Peng Lin Liu Qi Chen Xiaotao Han Yongkang Luo Liang Li 《Chinese Physics B》 2025年第4期625-625,共1页
Figure 3 in the paper[Chin.Phys.B 34020701(2025)]contains an axis labeling error.The revised figure is provided.This modification does not affect the result presented in the paper.
关键词 high-field magnet Cu-Ag alloy ultrasonic techniques elastic constants
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Advanced bioanalytical techniques for pharmacokinetic studies of nanocarrier drug delivery systems
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作者 Xiangjun Meng Jiayi Yao Jingkai Gu 《Journal of Pharmaceutical Analysis》 2025年第1期19-29,共11页
Significant investment in nanocarrier drug delivery systems(Nano-DDSs)has yielded only a limited number of successfully marketed nanomedicines,highlighting a low rate of clinical translation.A primary contributing fac... Significant investment in nanocarrier drug delivery systems(Nano-DDSs)has yielded only a limited number of successfully marketed nanomedicines,highlighting a low rate of clinical translation.A primary contributing factor is the lack of foundational understanding of in vivo processes.Comprehensive knowledge of the pharmacokinetics of Nano-DDSs is essential for developing more efficacious nanomedicines and accurately evaluating their safety and associated risks.However,the complexity of Nano-DDSs has impeded thorough and systematic pharmacokinetic studies.Key components of pharmacokinetic investigations on Nano-DDSs include the analysis of the released drug,the encapsulated drug,and the nanomaterial,which present a higher level of complexity compared to traditional small-molecule drugs.Establishing an appropriate approach for monitoring the pharmacokinetics of Nano-DDSs is crucial for facilitating the clinical translation of nanomedicines.This review provides an overview of advanced bioanalytical methodologies employed in studying the pharmacokinetics of anticancer organic Nano-DDSs over the past five years.We hope that this review will enhance the understanding of the pharmacokinetics of Nano-DDSs and support the advancement of nanomedicines. 展开更多
关键词 Nanocarrier drug delivery systems BIOANALYSIS PHARMACOKInetICS Sample fractionation technique
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基于改进EfficientNet-B0的轻量化苹果叶病害识别 被引量:1
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作者 王新皓 苏淑靖 +1 位作者 翟聪 文若铭 《农机化研究》 北大核心 2026年第3期137-144,共8页
为了对苹果叶片病害进行精准有效识别,提出了一种基于改进EfficientNet-B0的轻量级高精度识别模型——LC-EfficientNet。首先,在MBConv模块中引入无参数注意力模块SimAM,提高识别能力的同时不增加模型计算量;其次,结合ShuffleNetV2双分... 为了对苹果叶片病害进行精准有效识别,提出了一种基于改进EfficientNet-B0的轻量级高精度识别模型——LC-EfficientNet。首先,在MBConv模块中引入无参数注意力模块SimAM,提高识别能力的同时不增加模型计算量;其次,结合ShuffleNetV2双分支结构思想与MBConv生成改进模块HPRConv,充分利用双分支结构,使用深度可分离卷积后,引入通道混洗技术与通道拼接技术,显著减少计算量和参数量且提升了模型对不同层次特征的提取能力;最后,将激活函数由Swith换为Mish,以帮助模型更好地拟合数据,提升准确率。使用模型分别对PlantVillage和Appleleaf9苹果叶部病害数据集进行训练与测试实验,结果表明LC-EfficientNet模型在两个数据集上的分类准确率分别达到98.83%和94.67%,相较于原模型分别提升了1.11和2.26个百分点,参数量从5.3 MB左右降低到4.5 MB左右,在降低参数量的同时增加了准确率;与其他经典网络模型相比,LC-EfficientNet在各项性能评估指标上也均有所提升。研究可为苹果叶部病害识别提供新的解决方案。 展开更多
关键词 苹果叶 病害识别 卷积神经网络 轻量级 Efficientnet-B0 SimAM注意力模块 图像处理技术
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Key Techniques for High-yield and High-efficiency Cultivation of‘Zhouhua 5’Peanut under Film Mulching
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作者 Chaoyang JIA Yake LEI +3 位作者 Jianhang ZHANG Shijie ZHAN Chenwei DENG Jingbin CUI 《Agricultural Biotechnology》 2026年第1期13-15,25,共4页
With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall e... With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall economic benefits.Based on the varietal characteristics of‘Zhouhua 5’and addressing practical issues in peanut production,this paper summarized key techniques for high-yield and high-efficiency film mulching cultivation of this variety.These techniques cover all critical stages,including land preparation and fertilization,seed preparation,sowing methods,field management,and timely harvesting,providing technical guidance for varietal promotion and peanut production. 展开更多
关键词 PEANUT Zhouhua 5 Film mulching Key technique
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Prospects and potential mechanism of appropriate traditional Chinese medicine techniques for myopia treatment
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作者 Hui-Min Guo Hong-Mei Li Shu-Li Man 《Traditional Medicine Research》 2026年第1期100-114,共15页
Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating th... Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating this condition.Nevertheless,considering the vast amount of research that is currently being conducted,focusing on the utilization of TCM in the management of myopia,there is an urgent requirement for a thorough and comprehensive review.The review would serve to clarify the practical applications of TCM within this specific field,and it would also aim to elucidate the underlying mechanisms that are at play,providing a deeper understanding of how TCM principles can be effectively integrated into modern medical practices.Here,some modern medical pathogenesis of myopia and appropriate TCM techniques studies are summarized in the prevention and treatment of myopia.Further,we discussed the potential mechanisms and the future research directions of TCM against myopia.Identifying these mechanisms is crucial for understanding how TCM can be effectively utilized in this context.The combination of various TCM methods or the combination of traditional Chinese and Western medicine is of great significance for the prevention and control of myopia in the future. 展开更多
关键词 traditional Chinese medicine MYOPIA PATHOGENESIS appropriate TCM techniques
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Cerebrospinal fluid as a therapeutic medium for magnetic nanoparticle transport in brain cancer hyperthermia
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作者 Essam T Abdelwahab Ahmed A Elsawy +1 位作者 Abdallah A Henedy Sara I Abdelsalam 《Chinese Physics B》 2026年第2期475-490,共16页
Neuronanomedicine is a promising interdisciplinary field combining two critical fields,neuroscience and nanotechnology.This study focuses on the engineering of magnetized nanoparticles(MNPs)in diagnosing and treating ... Neuronanomedicine is a promising interdisciplinary field combining two critical fields,neuroscience and nanotechnology.This study focuses on the engineering of magnetized nanoparticles(MNPs)in diagnosing and treating neurological disorders and brain cancer.Additionally,this mechanism enhances the effectiveness of magnetic-guided drug delivery.The alternating magnetic field is applied to control the directions of the MNPs to target the tumor cells.This study approaches the radiotherapy techniques of magnetic hyperthermia therapy(MHT),wherein the thermal radiative heat transfer effect is applied to achieve homogenous heating to destroy cancer cells.MNPs are injected through the cerebrospinal fluid(CSF)transport in the glymphatic system.The elastic properties of the cerebral arteries cause peristaltic propulsion for the resulting nanofluid.Therefore,the effective Maxwell model for the nanofluid thermal conductivity is selected.The nanofluid governing equations are solved using the perturbation technique under small wavelength number and long wavelength approximation with small Reynolds number.Additionally,the effects of thermal slip and elastic properties boundary conditions are incorporated.The graphical results for the streamwise velocity,pressure,and temperature distributions are plotted using MATLAB package considering the different effects of the magnetic flux intensity,thermal radiation parameter,thermal slipping at boundaries,elastic wall properties,and nanoparticle concentration.The results demonstrate the strong impact of the magnetic field and radiation heating in terms of enhancing the nanofluid CSF flow behavior and destroying cancer. 展开更多
关键词 peristaltic flow thermal radiation magnetic field NANOFLUID perturbation technique
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Enhancing Heat Exchanger Performance through Passive Techniques:A Comprehensive Review
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作者 Muhammad Waheed Azam Uzair Sajjad +1 位作者 Faisal Maqbool Giovani Sempirini 《Frontiers in Heat and Mass Transfer》 2026年第1期25-53,共29页
Heat exchangers play a crucial role in thermal energy systems,with their performance directly impacting efficiency,cost,and environmental impact.Apowerful technique for performance improvement can be given by passive ... Heat exchangers play a crucial role in thermal energy systems,with their performance directly impacting efficiency,cost,and environmental impact.Apowerful technique for performance improvement can be given by passive enhancement strategies,which are characterized by their dependability and minimal external power requirements.This comprehensive review critically assesses recent advancements in such passive methods to evaluate their heat transfer mechanisms,performance characteristics,and practical implementation challenges.Our methodology involves a systematic and comprehensive analysis of various heat transfer enhancement techniques,including surface modifications,extended surfaces,swirl flow devices,and tube inserts.This approach synthesizes and integrates findings from a broad spectrum of experimental investigations and numerical simulations to establish a cohesive understanding of their performance characteristics and underlyingmechanisms.Based on the findings,passive heat transfer techniques result in significant improvements in thermal performance;for instance,corrugated and roughened surfaces increase the heat transfer coefficient by 50%–200%,and advanced insert geometries,such as modified twisted tapes,can increase it by more than 300%,typically accompanied by significant pressure-drop penalties.However,an important finding is the general trade-off between enhanced heat transfer and higher frictional loss,which requires optimization depending on the applications.Finally,this review also provides recommendations that will document the gaps of various passive techniques in heat exchangers to future address. 展开更多
关键词 Heat transfer enhancement passive techniques pressure drop heat exchangers
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Impact of Data Processing Techniques on AI Models for Attack-Based Imbalanced and Encrypted Traffic within IoT Environments
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作者 Yeasul Kim Chaeeun Won Hwankuk Kim 《Computers, Materials & Continua》 2026年第1期247-274,共28页
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp... With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy. 展开更多
关键词 Encrypted traffic attack detection data sampling technique AI-based detection IoT environment
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Algorithms for variational Monte Carlo calculations of fermion projected entangled pair states in the swap gates formulation and the detailed balance of tensor network sequential sampling
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作者 Yantao Wu Zhehao Dai 《Chinese Physics B》 2026年第2期226-232,共7页
In recent years,variational Monte Carlo(VMC)calculations of projected entangled pair states(PEPS)have emerged as a competitive method for computing the ground states of many-body quantum systems.This approach is parti... In recent years,variational Monte Carlo(VMC)calculations of projected entangled pair states(PEPS)have emerged as a competitive method for computing the ground states of many-body quantum systems.This approach is particularly important for fermionic systems,where sign problems are prevalent.We derive and explain the algorithms for VMC calculations of fermionic PEPS within the swap-gates formulation.As a separate key result,we prove the detailed balance for sequential sampling of tensor networks. 展开更多
关键词 fermion systems and electron gas computational techniques
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Research Advances in Modern Analytical Techniques for Quality Control and Clinical Application of Ganmai Dazao Decoction
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作者 Zihan Zhu 《Journal of Clinical and Nursing Research》 2026年第1期338-344,共7页
Ganmai Dazao Decoction,originating from“Jin Gui Yao Lue”(Synopsis of the Golden Chamber),is a classical prescription for treating visceral agitation.Composed of three medicinal and edible substances-licorice(Gancao)... Ganmai Dazao Decoction,originating from“Jin Gui Yao Lue”(Synopsis of the Golden Chamber),is a classical prescription for treating visceral agitation.Composed of three medicinal and edible substances-licorice(Gancao),wheat(Xiaomai),and jujube(Dazao),it functions to nourish the heart and calm the mind,harmonize the middle burner and regulate Qi,and alleviate urgency and restlessness.As its clinical application has expanded from traditional emotional disorders to neurological,endocrine,and various psychosomatic diseases,establishing a scientifically precise quality control system and deeply elucidating its pharmacodynamic material basis and mechanism of action have become critical tasks.Modern analytical methods,typified by chromatography,spectroscopy,and their hyphenated techniques,with their high sensitivity,high resolution,and powerful substance characterization capabilities,have become the core driving force for standardizing the quality control and modernizing the clinical application research of this formula.This paper systematically reviews the progress of the aforementioned analytical techniques and chemometrics in interpreting the chemical composition,establishing fingerprint profiles,controlling process quality,and researching the pharmacodynamic material basis of Ganmai Dazao Decoction.Furthermore,it discusses integrated approaches combining analytical techniques with pharmacology and clinical medicine to reveal mechanisms of action and explore therapeutic biomarkers.Finally,it provides an outlook on future directions and challenges,including technological integration and innovation,standardization of whole-process quality control systems,and evidence-based research aimed at internationalization. 展开更多
关键词 Ganmai Dazao Decoction Quality control Modern analytical techniques FINGERPRINT Pharmacodynamic material basis Clinical application
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Synaptic pruning mechanisms and application of emerging imaging techniques in neurological disorders
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作者 Yakang Xing Yi Mo +1 位作者 Qihui Chen Xiao Li 《Neural Regeneration Research》 2026年第5期1698-1714,共17页
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience... Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders. 展开更多
关键词 CHEMOKINE COMPLEMENT experience-dependent driven synaptic pruning imaging techniques NEUROGLIA signaling pathways synapse elimination synaptic pruning
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Nanjing Yunjin Brocade Weaving Technique
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《China Today》 2026年第1期80-80,共1页
THE Nanjing Yunjin brocade,known for its stunning luster,exquisite patterns,and a wealth of shades,represents the highest level of Chinese brocade craftsmanship.It was the designated textile for the imperial courts of... THE Nanjing Yunjin brocade,known for its stunning luster,exquisite patterns,and a wealth of shades,represents the highest level of Chinese brocade craftsmanship.It was the designated textile for the imperial courts of the Yuan(1206-1368),Ming(1368-1644),and Qing(1616-1911)dynasties,and is still highly regarded to this day. 展开更多
关键词 Nanjing Yunjin Yuan Dynasty Brocade Weaving technique Ming Dynasty Imperial Courts Chinese Brocade nanjing yunjin brocadeknown Qing Dynasty
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Hysteresis-Loop Criticality in Disordered Ferromagnets–A Comprehensive Review of Computational Techniques
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作者 Djordje Spasojevic Sanja Janicevic +1 位作者 Svetislav Mijatovic Bosiljka Tadic 《Computer Modeling in Engineering & Sciences》 2025年第2期1021-1107,共87页
Disordered ferromagnets with a domain structure that exhibit a hysteresis loop when driven by the external magnetic field are essential materials for modern technological applications.Therefore,the understanding and p... Disordered ferromagnets with a domain structure that exhibit a hysteresis loop when driven by the external magnetic field are essential materials for modern technological applications.Therefore,the understanding and potential for controlling the hysteresis phenomenon in thesematerials,especially concerning the disorder-induced critical behavior on the hysteresis loop,have attracted significant experimental,theoretical,and numerical research efforts.We review the challenges of the numerical modeling of physical phenomena behind the hysteresis loop critical behavior in disordered ferromagnetic systems related to the non-equilibriumstochastic dynamics of domain walls driven by external fields.Specifically,using the extended Random Field Ising Model,we present different simulation approaches and advanced numerical techniques that adequately describe the hysteresis loop shapes and the collective nature of the magnetization fluctuations associated with the criticality of the hysteresis loop for different sample shapes and varied parameters of disorder and rate of change of the external field,as well as the influence of thermal fluctuations and demagnetizing fields.The studied examples demonstrate how these numerical approaches reveal newphysical insights,providing quantitativemeasures of pertinent variables extracted from the systems’simulated or experimentally measured Barkhausen noise signals.The described computational techniques using inherent scale-invariance can be applied to the analysis of various complex systems,both quantum and classical,exhibiting non-equilibrium dynamical critical point or self-organized criticality. 展开更多
关键词 Disordered ferromagnets hysteresis-loop criticality magnetization-reversal avalanches in simulations and experiments zero-temperature and thermal Random Field Ising Model simulations computational techniques for multiparameter scaling analysis multifractal Barkhausen noise finite driving rates demagnetizing effects nonequilibrium critical dynamics
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In-situ stress solution theory for borehole overcoring technique incorporating time-dependent effect of stress relief and its applications
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作者 Daohong Xia Shengjun Miao +5 位作者 Lianjun Chen Yuan Li Zejing Liu Rongmin Zhang Pengjin Yang Pengcheng Li 《International Journal of Mining Science and Technology》 2026年第1期187-203,共17页
In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of roc... In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of rocks after stress relief introduces errors.To improve accuracy,this study proposes an in-situ stress solution theory that incorporates time-dependent stress relief effects.Triaxial stepwise loadingunloading rheological tests on granite and siltstone established quantitative relationships between instantaneous elastic recovery and viscoelastic recovery under different stress levels,confirming their impact on measurement accuracy.By integrating a dual-class elastic deformation recovery model,an improved in-situ stress solution theory was derived.Additionally,accounting for the nonlinear characteristics of rock masses,a determination method for time-dependent nonlinear mechanical parameters was proposed.Based on the CSIRO hollow inclusion strain cell,time-dependent strain correction equations and long-term confining pressure calibration equations were formulated.Finally,the proposed theory was successfully applied at one iron mine(736 m depth)in Xinjiang,China,and one coal mine(510 m depth)in Ningxia,China.Compared to classical theory,the calculated mean stress values showed accuracy improvements of 6.0%and 9.4%,respectively,validating the applicability and reliability of the proposed theory. 展开更多
关键词 In-situ stress solution theory Borehole overcoring technique Time-dependent effect of stress relief Viscoelastic recovery strain of rock In-situ stress measurement
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APPROXIMATION TECHNIQUES FOR APPLICATION OF GENETIC ALGORITHMS TO STRUCTURAL OPTIMIZATION 被引量:1
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作者 金海波 丁运亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期147-154,共8页
Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex str... Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex structural optimization problems, if the structural reanalysis technique is not adopted, the more the number of finite element analysis (FEA) is, the more the consuming time is. In the conventional structural optimization the number of FEA can be reduced by the structural reanalysis technique based on the approximation techniques and sensitivity analysis. With these techniques, this paper provides a new approximation model-segment approximation model, adopted for the GA application. This segment approximation model can decrease the number of FEA and increase the convergence rate of GA. So it can apparently decrease the computation time of GA. Two examples demonstrate the availability of the new segment approximation model. 展开更多
关键词 approximation techniques segment approximation model genetic algorithms structural optimization sensitivity analysis
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Finite element solution based on fast numerical technique for large-scale electromagnetic computation
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作者 赵阳 储家美 Satish Udpa 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期470-474,共5页
A numerical technique of the target-region locating (TRL) solver in conjunction with the wave-front method is presented for the application of the finite element method (FEM) for 3-D electromagnetic computation. F... A numerical technique of the target-region locating (TRL) solver in conjunction with the wave-front method is presented for the application of the finite element method (FEM) for 3-D electromagnetic computation. First, the principle of TRL technique is described. Then, the availability of TRL solver for nonlinear application is particularly discussed demonstrating that this solver can be easily used while still remaining great efficiency. The implementation on how to apply this technique in FEM based on magnetic vector potential (MVP) is also introduced. Finally, a numerical example of 3-D magnetostatic modeling using the TRL solver and FEMLAB is given. It shows that a huge computer resource can be saved by employing the new solver. 展开更多
关键词 finite element method electromagnetic computation numerical technique fast solver
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Novel magnetic compression technique for establishment of a canine model of tracheoesophageal fistula 被引量:24
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作者 Yi Gao Rong-Qian Wu +1 位作者 Yi Lv Xiao-Peng Yan 《World Journal of Gastroenterology》 SCIE CAS 2019年第30期4213-4221,共9页
BACKGROUND Clinically,tracheoesophageal fistula(TEF)is lack of effective surgical strategies.One reason is due to the lack of appropriate animal models of acquired TEF,which is usually complex and difficult.Recently,t... BACKGROUND Clinically,tracheoesophageal fistula(TEF)is lack of effective surgical strategies.One reason is due to the lack of appropriate animal models of acquired TEF,which is usually complex and difficult.Recently,the magnetic compression technique has been applied for digestive tract anastomosis or vascular anastomosis in animals.In this study,an animal model of TEF in dogs was developed by using the magnetic compression technique,hoping to provide a new method for mimicking TEF.AIM To establish a TEF model in dogs by using the magnetic compression technique.METHODS Six male beagles were used as models with two Nd-Fe-B permanent magnets for TEF.The parent magnet and the daughter magnet were placed in the cervical esophagus and trachea,respectively.The anterior wall of the esophagus and the posterior wall of the trachea were compressed when the two magnets coupled.After 4-6 d,the necrotic tissue between the two magnets fell off and the parent and daughter magnets disengaged from the target location,leaving a fistula.Gastroscopy/bronchoscopy,upper gastrointestinal contrast study,and histological analysis were performed.RESULTS The establishment of the TEF model in all six beagles was successful.The average time of magnet placement was 4.33±1.11 min(range,3-7 min).Mean time for the magnets to disengage from the target location was 4.67±0.75 d(range,4-6 d).TEFs were observed by gastroscopy/bronchoscopy and esophageal angiography.The gross anatomical structure of the esophagus and the trachea was in good condition.There was no esophageal mucosa or pseudostratified ciliated columnar epithelium at the site of the fistula according to histological analysis.CONCLUSION It is simple,feasible,and minimally invasive to use the magnetic compression technique for the establishment of the TEF model in dogs. 展开更多
关键词 MAGnetIC compression technique Tracheoesophageal FISTULA BEAGLE ANIMAL model
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Extrahepatic portacaval shunt via a magnetic compression technique: A cadaveric feasibility study 被引量:25
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作者 Xiao-Peng Yan Wen-Yan Liu +2 位作者 Jia Ma Jian-Peng Li Yi Lv 《World Journal of Gastroenterology》 SCIE CAS 2015年第26期8073-8080,共8页
AIM: To explore the anatomical feasibility of portacaval shunt using a magnetic compression technique(MCT) in cadavers.METHODS: Computed tomography(CT) images of 30 portal hypertensive patients were obtained.The diame... AIM: To explore the anatomical feasibility of portacaval shunt using a magnetic compression technique(MCT) in cadavers.METHODS: Computed tomography(CT) images of 30 portal hypertensive patients were obtained.The diameters of the portal vein(PV),the inferior vena cava(IVC),and distance between the two structures were measured.Similar measurements were performed on 20 adult corpses.The feasibility of portacaval shunt based on those measurements was analyzed.First stage of the extrahepatic portacaval shunt using MCT was performed on five cadavers.Specifically,the PV and IVC were exposed through an abdominal incision of the cadavers.The parent magnet was introduced from the femoral vein and was delivered into the IVC by an anchor wire and a 5F Cook catheter.The daughter magnet was introduced into the PV through the splenic vein using aninterventional guide wire.When the daughter magnet met the parent magnet,they automatically clipped together and the first stage of the portacaval shunt was set up.RESULTS: The average diameters of the PV and the IVC measured from the 30 CT image were 14.39 ± 2.36 mm and 18.59 ± 4.97 mm,respectively,and the maximum and minimum distances between the PV and the IVC were 9.79 ± 4.56 mm and 9.50 ± 4.79 mm,respectively.From 20 cadavers,the average diameters of the PV and the IVC were 14.48 ± 1.47 mm and 24.71 ± 2.64 mm,and the maximum and minimum distances between the PV and the IVC were 10.14 ± 1.70 mm and 8.93 ± 1.17 mm,respectively.The distances between the PV and the IVC from both the CT images and the cadavers were within the effective length of portacaval anastomosis using MCT(30.30 ± 4.19 mm).The PV and IVC are in close proximity to each other with no intervening tissues or structures in between.Simulated surgeries of the first stage using MCT on five cadavers was successfully performed.CONCLUSION: Anatomically,extrahepatic portacaval shunt employing MCT is highly feasible in humans. 展开更多
关键词 Portal vein INFERIOR vena cava Portacavalshunt MAGnetIC compression technique Anatomy CADAVER
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