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Application of support vector machine in trip chaining pattern recognition and analysis of explanatory variable effects 被引量:2
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作者 杨硕 邓卫 程龙 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期106-114,共9页
In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purpos... In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purposes by applying three methods: the support vector machine (SVM) model, the radial basis function neural network (RBFNN) model and the multinomial logit (MNL) model. The effect of explanatory factors on trip chaining behaviors and their contribution to model performace were investigated by sensitivity analysis. Results show that the SVM model has a better performance than the RBFNN model and the MNL model due to its higher overall and partial accuracy, indicating its recognition advantage under a smai sample size scenario. It is also proved that the SVM model is capable of estimating the effect of multi-category factors on trip chaining behaviors more accurately. The different contribution of explanatory, factors to trip chaining pattern recognition reflects the importance of refining trip chaining patterns ad exploring factors that are specific to each pattern. It is shown that the SVM technology in travel demand forecast modeling and analysis of explanatory variable effects is practical. 展开更多
关键词 trip chaining patterns support vector machine recognition performance sensitivity analysis
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Multi-Path Service Function Chaining for Mobile Surveillance of Animal Husbandry 被引量:1
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作者 Xi Chen Tao Wu Mehtab Afzal 《Computers, Materials & Continua》 SCIE EI 2022年第4期1959-1971,共13页
Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challe... Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challenges for the effective monitoring.Considering the dynamics of the field monitoring environment,as well as the diversity and mobility of monitoring targets,traditional WSN(Wireless Sensor Networks)or IoT(Internet of Things)is difficult to meet the surveillance needs.Mobile surveillance that features the collaboration of various functions(camera,sensing,image recognition,etc.)deployed on mobile devices is desirable in a volatile wireless environment.This paper proposes the service function chaining for mobile surveillance of animal husbandry,which orchestrates multi-path multifunction(MPMF)chains to help mobile devices to collaborate in complex surveillance tasks,provide backup chains in case the primary service function chain fails due to mobility,signal strength,obstacle,etc.,and make up for the defects of difficult deployment of monitoring facilities in ethnic areas.MPMF algorithmmodels both mobile devices and various functions deployed on them as abstract graph nodes,so that chains that are required to traverse various functions and hosting mobile devices can be orchestrated in a single graphbased query through modified and adapted Dijkstra-like algorithms,with their cost ordered automatically.Experiment results show that the proposed MPMF algorithm finds multiple least-costly chains that traverse demanded functions in a timely fashion on Raspberry Pi-equipped mobile devices. 展开更多
关键词 Service function chaining ORCHESTRATION SURVEILLANCE shortest path
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An IPC-based Prolog design pattern for integrating backward chaining inference into applications or embedded systems 被引量:2
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作者 Li Guoqi Shao Yuanxun +1 位作者 Hong Sheng Liu Bin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1571-1577,共7页
Prolog is one of the most important candidates to build expert systems and AI-related programs and has potential applications in embedded systems. However, Prolog is not suitable to develop many kinds of components, s... Prolog is one of the most important candidates to build expert systems and AI-related programs and has potential applications in embedded systems. However, Prolog is not suitable to develop many kinds of components, such as data acquisition and task scheduling, which are also crucial. To make the best use of the advantages and bypass the disadvantages, it is attractive to integrate Prolog with programs developed by other languages. In this paper, an IPC-based method is used to integrate backward chaining inference implemented by Prolog into applications or embedded systems. A Prolog design pattern is derived from the method for reuse, whose principle and definition are provided in detail. Additionally, the design pattern is applied to a target system, which is free software, to verify its feasibility. The detailed implementation of the application is given to clarify the design pattern. The design pattern can be further applied to wide range applications and embedded systems and the method described in this paper can also be adopted for other logic programming languages. 展开更多
关键词 Backward chaining inference Design method Embedded systems Inference engines Inter-process communication Prolog
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基于SDN的动态ServiceChaining方案
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作者 林鹏 《信息与电脑》 2020年第18期153-157,共5页
随着终端规模的不断增加和云计算的逐渐普及,园区网的业务越来越多样化,从而带来网络容量和带宽升级。基础网络升级后,园区边缘网络的专用设备(防火墙、广域网加速设备等)容易成为整个园区网的性能瓶颈点。而对这些专用设备进行升级和... 随着终端规模的不断增加和云计算的逐渐普及,园区网的业务越来越多样化,从而带来网络容量和带宽升级。基础网络升级后,园区边缘网络的专用设备(防火墙、广域网加速设备等)容易成为整个园区网的性能瓶颈点。而对这些专用设备进行升级和更换所带来的支出费用较大,同时由于这些设备都是专业的硬件设备,其部署配置和运维管理相对于交换机与路由器也较为复杂。如何利旧现有专用设备、降低改造费用成为园区网建设所需考虑的重要因素。本文通过引入SDN,阐述了如何基于SDN实现动态Service Chaining技术,实现按需引流。动态Service Chaining技术可实现网络出口智能引流、安全资源池化、网络安全协防,从而搭建一个富有弹性、高度可扩展的业务流处理平台。 展开更多
关键词 SDN Service chaining 安全池化
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’... Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease. 展开更多
关键词 ALPHA-SYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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Eliminating Redundant Search Space on Backtracking for Forward Chaining Theorem Proving
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作者 LifengHe YuyanChao HidenoriItoh 《Journal of Computer Science & Technology》 SCIE EI CSCD 2003年第5期580-591,共12页
This paper introduces some improvements on the intelligent backtrackingstrategy for forward chaining theorem proving. How to decide a minimal useful consequent atom setfor a refutation derived at a node in a proof tre... This paper introduces some improvements on the intelligent backtrackingstrategy for forward chaining theorem proving. How to decide a minimal useful consequent atom setfor a refutation derived at a node in a proof tree is discussed. In most cases, an unnecessarynon-Horn clause used for forward chaining will be split only once. The increase of the search spaceby invoking unnecessary forward chaining clauses will be nearly linear, not exponential anymore. Inthis paper, the principle of the proposed method and its correctness are introduced. Moreover, someexamples are provided to show that the proposed approach is powerful for forward chaining theoremproving. 展开更多
关键词 theorem proving forward chaining SATCHMO I-SATCHMO model generation
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Logic Programs,Compatibility and Forward Chaining Construction
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作者 王以松 张明义 犹嘉槐 《Journal of Computer Science & Technology》 SCIE EI CSCD 2009年第6期1125-1137,共13页
Logic programming under the stable model semantics is proposed as a non-monotonic language for knowledge representation and reasoning in artificial intelligence. In this paper, we explore and extend the notion of comp... Logic programming under the stable model semantics is proposed as a non-monotonic language for knowledge representation and reasoning in artificial intelligence. In this paper, we explore and extend the notion of compatibility and the A operator, which were first proposed by Zhang to characterize default theories. First, we present a new characterization of stable models of a logic program and show that an extended notion of compatibility can characterize stable submodels. We further propose the notion of weak auto-compatibility which characterizes the Normal Forward Chaining Construction proposed by Marek, Nerode and Remmel. Previously, this construction was only known to construct the stable models of FC-normal logic programs, which turn out to be a proper subclass of weakly auto-compatible logic programs. We investigate the properties and complexity issues for weakly auto-compatible logic programs and compare them with some subclasses of logic programs. 展开更多
关键词 artificial intelligence default theory answer set compatibility forward chaining
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Chain architecture-engineered artesunate nanoassemblies target LONP1 to induce oxidative damage for enhanced anti-tumor therapy
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作者 Yupeng Wang Xinxin Sun +5 位作者 Jianbin Shi Zhixiao Zhang Jin Sun Cong Luo Zhonggui He Shenwu Zhang 《Chinese Chemical Letters》 2026年第1期497-502,共6页
Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the del... Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the delivery efficiency,we engineered three artesunate(ART) derivatives,AC_(15)-L(linear),AC_(15)-B(branched),and AC_(15)-C(cyclic) with distinct aliphatic chain architectures.Unexpectedly,we observed that AC_(15)-C exhibited superior cytotoxicity against 4T1 breast cancer cells,and had the highest binding affinity for Lon protease 1(LONP1)(-72.6 kcal/mol).Subsequently,disulfide bond-containing lipid-PEG(DSPESS-PEG2K) modified chain architecture-engineered ART derivatives nanoassemblies(NAs) were developed to mitigate solubility-related limitations while enhancing targeting precision.Molecular docking and experimental validation demonstrated that ART derivatives inhibited LONP1 through hydrophobic interactions while preserved Fe^(2+)-mediated Fenton-like reaction activity.In vitro and in vivo evaluations demonstrated that AC_(15)-C NAs outperformed free ART and other NAs,suppressing 4T1 tumor growth via dual action:LONP1-directed mitochondrial proteostasis collapse and reactive oxygen species(ROS) amplification through Fe^(2+)-ART interactions.This study elucidated a novel anti-tumor mechanism of ART through the rational design of derivatives with spatially configured aliphatic chains,and developed reductionresponsive NAs to provide an advanced delivery strategy. 展开更多
关键词 Chain architecture engineering ART LONP1 NANOASSEMBLIES Cancer therapy
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Resilience and risk management in railway supply chains:the interplay of leadership,innovation and competitive advantage
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作者 Meisam Karami 《Railway Sciences》 2026年第1期117-135,共19页
Purpose-This study explores how managerial leadership and organizational innovation interact to enhance resilience and risk management in railway supply chains and how these capabilities contribute to sustained compet... Purpose-This study explores how managerial leadership and organizational innovation interact to enhance resilience and risk management in railway supply chains and how these capabilities contribute to sustained competitive advantage.It emphasizes the strategic importance of resilience in railway systems that face operational complexity,regulatory pressures and increasing exposure to systemic risks.Design/methodology/approach-A mixed-methods design was employed,integrating survey data from 186 railway organizations with six case studies involving railway operators,rolling stock manufacturers and supply chain partners across multiple regions.Constructs were measured using validated scales and hypothesized relationships were tested using Structural Equation Modeling(SEM).Case study interviews were analyzed thematically to provide contextual understanding of leadership practices and innovation strategies.Findings-The results confirm that transformational managerial leadership significantly predicts innovation adoption,which in turn strengthens resilience and risk management capabilities.Resilience emerged as a powerful driver of competitive advantage,reinforcing its role as a strategic capability rather than a reactive response to disruptions.Furthermore,innovation was shown to partially mediate the relationship between leadership and resilience,highlighting its function as the operational channel through which vision translates into capability.Originality/value-This study contributes to the literature by integrating the Resource-Based View(RBV)and Dynamic Capabilities(DC)framework into the context of railway supply chains.It is among the first to empirically validate the mediating role of innovation between leadership and resilience,offering both theoretical advancements and actionable strategies for building resilient and competitive railway systems. 展开更多
关键词 Railway supply chains RESILIENCE Risk management LEADERSHIP INNOVATION Competitive advantage
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DPIL-Traj: Differential Privacy Trajectory Generation Framework with Imitation Learning
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作者 Huaxiong Liao Xiangxuan Zhong +4 位作者 Xueqi Chen Yirui Huang Yuwei Lin Jing Zhang Bruce Gu 《Computers, Materials & Continua》 2026年第1期1530-1550,共21页
The generation of synthetic trajectories has become essential in various fields for analyzing complex movement patterns.However,the use of real-world trajectory data poses significant privacy risks,such as location re... The generation of synthetic trajectories has become essential in various fields for analyzing complex movement patterns.However,the use of real-world trajectory data poses significant privacy risks,such as location reidentification and correlation attacks.To address these challenges,privacy-preserving trajectory generation methods are critical for applications relying on sensitive location data.This paper introduces DPIL-Traj,an advanced framework designed to generate synthetic trajectories while achieving a superior balance between data utility and privacy preservation.Firstly,the framework incorporates Differential Privacy Clustering,which anonymizes trajectory data by applying differential privacy techniques that add noise,ensuring the protection of sensitive user information.Secondly,Imitation Learning is used to replicate decision-making behaviors observed in real-world trajectories.By learning from expert trajectories,this component generates synthetic data that closely mimics real-world decision-making processes while optimizing the quality of the generated trajectories.Finally,Markov-based Trajectory Generation is employed to capture and maintain the inherent temporal dynamics of movement patterns.Extensive experiments conducted on the GeoLife trajectory dataset show that DPIL-Traj improves utility performance by an average of 19.85%,and in terms of privacy performance by an average of 12.51%,compared to state-of-the-art approaches.Ablation studies further reveal that DP clustering effectively safeguards privacy,imitation learning enhances utility under noise,and the Markov module strengthens temporal coherence. 展开更多
关键词 PRIVACY-PRESERVING trajectory generation differential privacy imitation learning Markov chain
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Transmission Characteristics of Biological Pollutant on Cold Surface Through Surface Contact During Cold Storage
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作者 Zhiqiang Wang Lixin Chen +3 位作者 Saiwei Ge Wei Xiao Zhuohao Xuan Pengcheng Zhang 《Journal of Harbin Institute of Technology(New Series)》 2026年第1期20-32,共13页
The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfa... The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfaces.A quantitative statistical experimental method was adopted to study the surface⁃contact transmission of micro⁃organisms,wherein the transfer rate of surface contact was the dependent variable and Escherichia coli was used as the indicator bacterium.The effects of contact pressure(0.44,0.86,1.55,2.25,and 2.94 N/cm^(2)),contact time(0,15,30,45,and 60 s),contact angle(15°and 25°),and surface materials(rubber and cotton gloves)were measured at two storage temperatures:cold storage(5℃)and freezing(-18℃).The results showed that as temperature decreases,the transfer of micro⁃organisms through surface contact becomes less probable.The contact time did not significantly influence the transfer rate of micro⁃organisms when items were handled at cold⁃storage temperatures.Based on these results,we recommend placing items as flat as possible to minimize the tilt angle when handling them at cold⁃storage temperatures.Additionally,if the tilt angle cannot be avoided,rubber gloves should be used when handling items stored at large tilt angles,whereas cotton gloves may be used for items placed at smaller angles. 展开更多
关键词 cold chain biological pollutant surface contact transfer rate transmission characteristics
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The five major textile and apparel industry clusters in Xinjiang have achieved an output value exceeding 220 billion yuan
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作者 Qiu Shuchen 《China Textile》 2026年第1期34-35,共2页
In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further... In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further extending to apparel,home textiles,and industrial textiles.In November 2025,the first list of five characteristic textile and apparel industry clusters in Xinjiang was officially announced,marking a new stage in the clustering of Xinjiang's textile and apparel industry.Data shows that the total output value of Xinjiang's cotton and textile and apparel industry chain has exceeded 220 billion yuan.With the nation's largest cotton production,a complete industrial chain system,and strong synergistic effects,Xinjiang has become a leading and highly competitive textile industry hub in China. 展开更多
关键词 clustering XINJIANG cotton production apparel industry chemical fiber industrial chain textile industry output value
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Discrete Polyesters Featuring a Cyclic Pendant Group
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作者 Shuai Wang Qin He +3 位作者 Xi-Tong Chen Dong-Dong Zhou Zhan-Hui Gan Xue-Hui Dong 《Chinese Journal of Polymer Science》 2026年第2期416-422,I0012,共8页
In contrast to cyclic polymers with ring-like backbones,side-chain cyclization is another intriguing structural feature that has not been extensively studied.In this study,a library of orthogonally protected monomers ... In contrast to cyclic polymers with ring-like backbones,side-chain cyclization is another intriguing structural feature that has not been extensively studied.In this study,a library of orthogonally protected monomers featuring monocyclic,dicyclic,or tricyclic pendant motifs was designed and prepared based on malic acid derivatives.Polyesters with precise chemical structures and uniform chain lengths were prepared modularly through iterative growth.Meticulous control over the chemical details allows for a close investigation of the topological effects on the polymer properties.Compared to their linear side chain counterparts,the presence of cyclic pendant groups has a significant impact on chain conformation,leading to a reduction in hydrodynamic volume and an enhancement in the glass transition temperature.These results underscore the potential of tailoring polymer properties through rational engineering of side chain topology. 展开更多
关键词 Discrete polymer Iterative growth Side chain topology Cyclic conformation
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A numerical model for cascading glacier mass flow analysis(GMFA):Erosion-deposition dynamics,phase changes,and multi-hazard chain transformations
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作者 Ruochen Jiang Limin Zhang +4 位作者 Wenjun Lu Dalei Peng Xin He Shihao Xiao Mingdong Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期299-316,共18页
Glacier landslide cascading hazards pose threats to communities and infrastructure,affected by complex processes including the amplification of mass flow volume through erosion and entrainment,transformation of hazard... Glacier landslide cascading hazards pose threats to communities and infrastructure,affected by complex processes including the amplification of mass flow volume through erosion and entrainment,transformation of hazard types,ice-water phase change,and enhanced mobility of the mass flow.Scientifically simulating these physical phenomena proves challenging.This study introduces GMFA(glacier mass flow analysis),an integrated numerical model that advances the field by:(1)proposing depth-averaged fluctuation energy and internal energy equations,(2)incorporating the ice-water phase change and the entrainment-deposition process,and(3)capturing their effects on mass flow runout characteristics.The model employs the finite volume method to solve the multi-physics coupled governing equations,enabling efficient large-scale simulations.The model is verified through three numerical tests covering flow dynamics,temperature evolution,and thermo-hydro-mechanical runout processes.The model is applied to analyze a hazard chain that occurred on 10 September 2020 on the Tibetan Plateau.The multi-scenario simulation results indicate an entrained mass volume of(4.95±0.11)×10^(5)m^(3),and a ratio of entrained mass volume to source material volume of 0.44.The solid concentration decreases from 0.6-0.7 to 0.1-0.15 with increasing runout distance,indicating a transition from avalanche to debris flood.The internal energy rises by(3-4)×10^(3)kJ/m^(3),driving rapid ice melting from 0.1 to 0.2 to near-zero concentration.The model effectively quantifies volume amplification,ice-water phase changes,and multi-hazard transformations.This model pushes the geoscience frontier,extending computational capability from single-to multi-hazard simulations and providing a powerful tool for analyzing glacier cascading hazards. 展开更多
关键词 Glacier hazard chains LANDSLIDES Debris flows Phase change Erosion and deposition Hazard transformation
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Prognostic Scoring Systems in Ossiculoplasty:A Comprehensive Review and Introduction of a Novel Predictive Index
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作者 Goran Latif Omer Giuseppe De Donato +5 位作者 Aland Salih Abdullah Sahand Soran Ali Rekawt Hama Rashid Kareem Andrea Gravina Saeed Sherko F.Zmnako Stefano Di Girolamo 《Journal of Otology》 2026年第1期57-64,共8页
Ossiculoplasty remains a challenging surgical procedure,with outcomes heavily influenced by diverse anatomical and pathological factors.Over the decades,numerous scoring systems have been developed to predict the prog... Ossiculoplasty remains a challenging surgical procedure,with outcomes heavily influenced by diverse anatomical and pathological factors.Over the decades,numerous scoring systems have been developed to predict the prognosis of ossiculoplasty,each emphasizing different variables such as ossicular status,middle ear environment,and surgical history.This paper provides a comprehensive review of the evolution of prognostic scoring systems,including Austin's original ossicular classification,Bellucci's otorrhea staging,the Middle Ear Risk Index(MERI),the Ossiculoplasty Outcome Parameter Staging(OOPS),and the recently introduced Ear Environment Risk(EER)scale.While these systems have significantly contributed to preoperative assessment,each presents notable limitations in encompassing all variables affecting surgical success.Therefore,the aim of this paper is to provide a review of the ossiculoplasty prognostic scores and show the benefits,innovations and gaps associated with each.To address these gaps,a novel,modified scoring system is proposed,incorporating previously overlooked but clinically significant factors such as tympanic membrane status,type of tympanoplasty,ossicular replacement material,CT scan findings,and the presence of complicated ear conditions.By synthesizing elements from historical scores with updated clinical insights,the proposed system aims to provide a more holistic and predictive framework for preoperative evaluation.Future multicenter studies are encouraged to validate the efficacy and prognostic power of this new scoring system,with the goal of improving surgical planning and patient counseling in ossiculoplasty. 展开更多
关键词 OSSICULOPLASTY Prognostic Scoring System Middle Ear Surgery Hearing Outcome Ossicular Chain Reconstruction
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Ultrafast Laser Shock Straining in Chiral Chain 2D Materials:Mold Topology‑Controlled Anisotropic Deformation
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作者 Xingtao Liu Danilo de Camargo Branco +5 位作者 Licong An Mingyi Wang Haoqing Jiang Ruoxing Wang Wenzhuo Wu Gary J.Cheng 《Nano-Micro Letters》 2026年第3期274-289,共16页
Tellurene,a chiral chain semiconductor with a narrow bandgap and exceptional strain sensitivity,emerges as a pivotal material for tailoring electronic and optoelectronic properties via strain engineering.This study el... Tellurene,a chiral chain semiconductor with a narrow bandgap and exceptional strain sensitivity,emerges as a pivotal material for tailoring electronic and optoelectronic properties via strain engineering.This study elucidates the fundamental mechanisms of ultrafast laser shock imprinting(LSI)in two-dimensional tellurium(Te),establishing a direct relationship between strain field orientation,mold topology,and anisotropic structural evolution.This is the first demonstration of ultrafast LSI on chiral chain Te unveiling orientation-sensitive dislocation networks.By applying controlled strain fields parallel or transverse to Te’s helical chains,we uncover two distinct deformation regimes.Strain aligned parallel to the chain’s direction induces gliding and rotation governed by weak interchain interactions,preserving covalent intrachain bonds and vibrational modes.In contrast,transverse strain drives shear-mediated multimodal deformations—tensile stretching,compression,and bending—resulting in significant lattice distortions and electronic property modulation.We discovered the critical role of mold topology on deformation:sharp-edged gratings generate localized shear forces surpassing those from homogeneous strain fields via smooth CD molds,triggering dislocation tangle formation,lattice reorientation,and inhomogeneous plastic deformation.Asymmetrical strain configurations enable localized structural transformations while retaining single-crystal integrity in adjacent regions—a balance essential for functional device integration.These insights position LSI as a precision tool for nanoscale strain engineering,capable of sculpting 2D material morphologies without compromising crystallinity.By bridging ultrafast mechanics with chiral chain material science,this work advances the design of strain-tunable devices for next-generation electronics and optoelectronics,while establishing a universal framework for manipulating anisotropic 2D systems under extreme strain rates.This work discovered crystallographic orientation-dependent deformation mechanisms in 2D Te,linking parallel strain to chain gliding and transverse strain to shear-driven multimodal distortion.It demonstrates mold geometry as a critical lever for strain localization and dislocation dynamics,with sharp-edged gratings enabling unprecedented control over lattice reorientation.Crucially,the identification of strain field conditions that reconcile severe plastic deformation with single-crystal retention offers a pathway to functional nanostructure fabrication,redefining LSI’s potential in ultrafast strain engineering of chiral chain materials. 展开更多
关键词 Tellurene Laser shock imprinting Strain engineering Anisotropic deformation Chiral chain semiconductor Dislocation dynamics
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Social Network and Value Chain Integration:Unraveling the Formation and Evolution of Meizhou Pomelo Industry Cluster in China
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作者 YANG Ren LIN Yuancheng ZHANG Xin 《Chinese Geographical Science》 2026年第2期239-255,共17页
The shift toward specialized and large-scale agricultural production has spurred the emergence of agricultural clusters as key forces of rural vitalization and sustainable development.This paper explored the formation... The shift toward specialized and large-scale agricultural production has spurred the emergence of agricultural clusters as key forces of rural vitalization and sustainable development.This paper explored the formation and evolution of Meizhou pomelo industry cluster in China,focusing on its role in restructuring rural socio-economic systems and integrating the whole value chains.Based on a case study employing qualitative methods such as in-depth interviews and participatory observation,the agricultural cluster evolution of Meizhou pomelo was categorized into three key phases of initial decentralization,self-organized scaling,and reorganized clustering.Geographical proximity and industrial agglomeration constitute the physical foundation,while vertical/horizontal linkages,technologic-al innovation,and policy support enhance competitiveness.Special mechanisms emerge through localized social networks,farmer co-operatives’activation,and cross-regional market expansion.The cluster’s impact is manifested in the shift from extensive to standard-ized and modernized production,diversified and flexible livelihood of farmers,and the integration of agriculture with industry and ser-vices.The development of the whole value chain based on agricultural cluster represents a critical pathway for achieving agricultural modernization,encompassing both internal and external value chain optimization.Through quality assurance systems,product diversi-fication strategies,operational efficiency improvements,and brand enhancement,these clusters amplify product value propositions and market competitiveness.This systemic approach facilitates supply-demand coordination,enables resource synergies,and optimizes eco-nomic returns across the horizontal and vertical value chain.This paper argues that agricultural clusters serve as strategic catalysts for sustainable rural development by reconstructing local production systems,fostering innovation ecosystems,and aligning agricultural modernization.It contributes to debates on rural vitalization by demonstrating how agricultural clustering can reconfigure rural areas as hubs of ecological modernization,rather than mere urban peripheries. 展开更多
关键词 agricultural cluster sustainable rural development agricultural systems social network whole value chain China
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Mechanism and evolution of a deep-seated liquefaction-induced flow slide disaster chain triggered by the M 6.2 Jishishan earthquake,Gansu,China
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作者 Li Zhaoyan Wang Zifa Yuan Jinyuan 《Earthquake Engineering and Engineering Vibration》 2026年第1期1-12,共12页
On December 18,2023,a magnitude 6.2 earthquake struck Jishishan County,Gansu Province,triggering a liquefaction-induced flow slide along the loess-mudstone contact zone and causing significant casualties and property ... On December 18,2023,a magnitude 6.2 earthquake struck Jishishan County,Gansu Province,triggering a liquefaction-induced flow slide along the loess-mudstone contact zone and causing significant casualties and property losses.The event featured low-slope,large-scale,runout distance sliding and exhibited a clear cascading disaster chain.Its characteristics closely resemble the catastrophic mudflow at the nearby Lajia Ruins approximately 4,000 years ago.Using high-resolution oblique photogrammetry,cone penetration testing,surface wave analysis,and horizontal-to-vertical spectral ratio methods,this study examines the stratigraphy,groundwater conditions,and geomechanical properties of the affected zone.Results indicate that saturated loess overlying impermeable mudstone formed a high-moisture mass vulnerable to seismic disturbance.Seismic resonance triggered the liquefaction of weakly structured loess,which slide along the contact interface and evolved into a runout distance mudflow.Underground water and terrain modification created a composite weak zone of saturated loess and softened mudstone,which intensified the disaster chain-from earthquake to liquefaction,flow slide,and mudflow.This study contributes to the understanding of deep-seated liquefaction-flow slide disasters,thereby advancing more effective risk mitigation strategies in the Loess Plateau and comparable loess-covered seismic regions. 展开更多
关键词 Jishishan earthquake Lajia Ruins coupled disaster chain deep-seated liquefaction liquefaction-induced flow slide
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Process analysis of columnar dangerous rock mass collapse in the Three Gorges Reservoir Area based on 3D MPM
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作者 CHENG Shulou HUANG Bolin +3 位作者 ZHANG Peng LI Qiuwang DONG Xingchen Qin Panpan 《Journal of Mountain Science》 2026年第1期237-253,共17页
The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi ... The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi columnar dangerous rock mass(CCDRM)through field surveys and simulated its collapse dynamics with Material Point Method(MPM),and analyzed the collapse-diffusionsurge generation mechanisms.Field investigations revealed a 0.8 m-thick lotus-like extrusion structure at the base,severely degraded by cyclic water fluctuations,predisposing the rock mass to base-crushing failure.Numerical simulations indicate collapse velocities up to 42 m/s,amplified spreading with a 318 m deposition range and 11 m maximum thickness,and two major collisions causing 50%-60%velocity reduction.Gully topography buffers kinetic energy,retaining 5%debris on slopes and channeling 7%into the river.High-speed river impact generates a 20 m-diameter cavity,producing an 11 m surge,identifying the Guandukou Town waterfront 1.2 km downstream as a high-risk zone.These results clarify the collapse mechanisms of columnar dangerous rock mass and inform its hazard mitigation strategies. 展开更多
关键词 Dangerous rock mass Material Point Method Three-dimensional numerical simulation Disaster chain SURGE
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SPG contributes wisdom and strength to cultivating international standardization talent
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作者 Xu Guowang 《China Standardization》 2026年第1期46-46,共1页
Established in 2019,the Shandong Port Group(SPG)comprises four port groups(Qingdao Port,Rizhao Port,Yantai Port,and Bohaiwan Port)and 12 business segments.SPG connects 3,345 kilometers of coastline within Shandong Pro... Established in 2019,the Shandong Port Group(SPG)comprises four port groups(Qingdao Port,Rizhao Port,Yantai Port,and Bohaiwan Port)and 12 business segments.SPG connects 3,345 kilometers of coastline within Shandong Province.Its cargo throughput has consistently ranked first globally for many years,and its container volume growth ranks second globally,forming a port cluster covering the entire industrial chain. 展开更多
关键词 port cluster port groups talent cultivation industrial chain international standardization Shandong Port Group cargo throughput container volume
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