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Multi-agent Based Modeling of Manufacturing Network
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作者 GUO Yuming SUN Yanming ZHENG Shixiong 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期381-387,共7页
An intelligent manufacturing system is modeled currently from the viewpoint of manufacturing applications,and the network platform’s influence to manufacturing applications is not considered adequately.However any bo... An intelligent manufacturing system is modeled currently from the viewpoint of manufacturing applications,and the network platform’s influence to manufacturing applications is not considered adequately.However any bottleneck in service oriented architecture(SOA)for the manufacturing network can affect the agility of the IT environment.In this paper,to achieve a trade-off between manufacturing resources and network resources,the manufacturing network is modeled with multi-agent,in which two kinds of basic elements,the manufacturing application unit and the network carrier of manufacturing information,are presented.And their main characters are described by colored petri net.The manufacturing application model drives the network platform that inversely provides this application model technology supports.The proposed multi-agent system is demonstrated through an example integration scenario involving production plan,resources management and execution subsystems.And the result suggests that analyzing and designing the system architecture of networked manufacturing should give due attention to the operation system as well as manufacturing applications. 展开更多
关键词 manufacturing network model multi-agent colored petri net SOA
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Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch 被引量:19
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作者 王维军 屈香菊 郭林亮 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期223-231,共9页
With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as ... With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as aggregation agents, the detailed components like catapult, landing gears, and disturbances are considered as meta-agents, which belong to their aggregation agent. Thus, the model with two layers is formed i.e. the aggregation agent layer and the meta-agent layer. The information communication among all agents is described. The meta-agents within one aggregation agent communicate with each other directly by information sharing, but the meta-agents, which belong to different aggregation agents exchange their information through the aggregation layer first, and then perceive it from the sharing environment, that is the aggregation agent. Thus, not only the hierarchy model is built, but also the environment perceived by each agent is specified. Meanwhile, the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved. Each agent involved in carrier-based aircraft catapult launch is depicted, with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier, aircraft, and landing gears. The models of reactive agents among them are derived based on tensors, and the perceived messages and inner frameworks of each agent are characterized. Finally, some results of a simulation instance are given. The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely. The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system. This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent, and it is convenient to expand, maintain, and reuse the program codes. 展开更多
关键词 multi-agent system (MAS) multi-agent based modeling (MABM) TENSOR carrier-based aircraft catapult launch hierarchy simulation model
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Secured-FL:Blockchain-Based Defense against Adversarial Attacks on Federated Learning Models
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作者 Bello Musa Yakubu Nor Shahida Mohd Jamail +1 位作者 Rabia Latif Seemab Latif 《Computers, Materials & Continua》 2026年第3期734-757,共24页
Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work pr... Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments. 展开更多
关键词 Federated learning(FL) blockchain FL based privacy model defense FL model security ethereum smart contract
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Immune multi-agent model using vaccine for cooperative air-defense system of systems for surface warship formation based on danger theory 被引量:9
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作者 Jun Wang Xiaozhe Zhao +2 位作者 Beiping Xu Wei Wang Zhiyong Niu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期946-953,共8页
Aiming at the problem on cooperative air-defense of surface warship formation, this paper maps the cooperative airdefense system of systems (SoS) for surface warship formation (CASoSSWF) to the biological immune s... Aiming at the problem on cooperative air-defense of surface warship formation, this paper maps the cooperative airdefense system of systems (SoS) for surface warship formation (CASoSSWF) to the biological immune system (BIS) according to the similarity of the defense mechanism and characteristics between the CASoSSWF and the BIS, and then designs the models of components and the architecture for a monitoring agent, a regulating agent, a killer agent, a pre-warning agent and a communicating agent by making use of the theories and methods of the artificial immune system, the multi-agent system (MAS), the vaccine and the danger theory (DT). Moreover a new immune multi-agent model using vaccine based on DT (IMMUVBDT) for the cooperative air-defense SoS is advanced. The immune response and immune mechanism of the CASoSSWF are analyzed. The model has a capability of memory, evolution, commendable dynamic environment adaptability and self-learning, and embodies adequately the cooperative air-defense mechanism for the CASoSSWF. Therefore it shows a novel idea for the CASoSSWF which can provide conception models for a surface warship formation operation simulation system. 展开更多
关键词 immune multi-agent model (IMM) VACCINE surface warship formation cooperative air-defense system of systems (CASoS) danger theory (DT)
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Multi-Step Model Predictive Control Based on Online Support Vector Regression Optimized by Multi-Agent Particle Swarm Optimization Algorithm 被引量:2
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作者 TANG Xianlun LIU Nianci +1 位作者 WAN Yali GUO Fei 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第5期607-612,共6页
As optimization of parameters affects prediction accuracy and generalization ability of support vector regression(SVR) greatly and the predictive model often mismatches nonlinear system model predictive control,a mult... As optimization of parameters affects prediction accuracy and generalization ability of support vector regression(SVR) greatly and the predictive model often mismatches nonlinear system model predictive control,a multi-step model predictive control based on online SVR(OSVR) optimized by multi-agent particle swarm optimization algorithm(MAPSO) is put forward. By integrating the online learning ability of OSVR, the predictive model can self-correct and adapt to the dynamic changes in nonlinear process well. 展开更多
关键词 online support VECTOR regression (OSVR) model PREDICTIVE CONTROLLER (MPC) multi-agent particleswarm optimization (MAPSO) nonlinear systems
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Using Agent-Based Modeling to Study the Adaptation and Evolution of Human Emotions and Cognition
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作者 Duan Qin Luo Siyang 《心理科学》 北大核心 2025年第6期1314-1332,共19页
This review explores the use of agent-based modeling(ABM)within the framework of study human emotion and cognition in the context of its ability to simulate complex social interactions,adaptive changes,and evolutionar... This review explores the use of agent-based modeling(ABM)within the framework of study human emotion and cognition in the context of its ability to simulate complex social interactions,adaptive changes,and evolutionary processes.By representing agents and their defined environments with probabilistic interactions,ABM allows the assessment of the effects of individual behavior at the micro level on the greater social phenomena at the macro level.The review looks into the applications of ABM in portraying some of the key components of emotions and cognition-empathy,cooperation,decision making,and emotional transmission-and analyzes the problems including scalability,empirical validation,and description of sensitive emotional states.The most important conclusion is that merging ABM with information neurobiological data and artificial intelligence(AI)techniques would allow for deepening the interactions within the system and enhancing its responsiveness to stimuli.This review highlights approaches that aim to exploit the ABM methodology more fully and integrates methods from biology,neuroscience,and engineering.This integration could contribute to our understanding of the human behavior evolution and adaptation within systems relevant to policymaking,healthcare,and education. 展开更多
关键词 agent-based modeling emotions evolution cognition evolution social interactions
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A Multi-Agent Based Model for User Interest Mining on Sina Weibo
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作者 Meijia Wang Qingshan Li 《China Communications》 SCIE CSCD 2022年第2期225-234,共10页
User interest mining on Sina Weibo is the basis of personalized recommendations,advertising,marketing promotions,and other tasks.Although great progress has been made in this area,previous studies have ignored the dif... User interest mining on Sina Weibo is the basis of personalized recommendations,advertising,marketing promotions,and other tasks.Although great progress has been made in this area,previous studies have ignored the differences among users:the varied behaviors and habits that lead to unique user data characteristics.It is unreasonable to use a single strategy to mine interests from such varied user data.Therefore,this paper proposes an adaptive model for user interest mining based on a multi-agent system whose input includes self-descriptive user data,microblogs and correlations.This method has the ability to select the appropriate strategy based on each user’s data characteristics.The experimental results show that the proposed method performs better than the baselines. 展开更多
关键词 multi-agent system user interest mining adaptive model Sina Weibo online social network
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Computation Tree Logic Model Checking of Multi-Agent Systems Based on Fuzzy Epistemic Interpreted Systems
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作者 Xia Li Zhanyou Ma +3 位作者 Zhibao Mian Ziyuan Liu Ruiqi Huang Nana He 《Computers, Materials & Continua》 SCIE EI 2024年第3期4129-4152,共24页
Model checking is an automated formal verification method to verify whether epistemic multi-agent systems adhere to property specifications.Although there is an extensive literature on qualitative properties such as s... Model checking is an automated formal verification method to verify whether epistemic multi-agent systems adhere to property specifications.Although there is an extensive literature on qualitative properties such as safety and liveness,there is still a lack of quantitative and uncertain property verifications for these systems.In uncertain environments,agents must make judicious decisions based on subjective epistemic.To verify epistemic and measurable properties in multi-agent systems,this paper extends fuzzy computation tree logic by introducing epistemic modalities and proposing a new Fuzzy Computation Tree Logic of Knowledge(FCTLK).We represent fuzzy multi-agent systems as distributed knowledge bases with fuzzy epistemic interpreted systems.In addition,we provide a transformation algorithm from fuzzy epistemic interpreted systems to fuzzy Kripke structures,as well as transformation rules from FCTLK formulas to Fuzzy Computation Tree Logic(FCTL)formulas.Accordingly,we transform the FCTLK model checking problem into the FCTL model checking.This enables the verification of FCTLK formulas by using the fuzzy model checking algorithm of FCTL without additional computational overheads.Finally,we present correctness proofs and complexity analyses of the proposed algorithms.Additionally,we further illustrate the practical application of our approach through an example of a train control system. 展开更多
关键词 model checking multi-agent systems fuzzy epistemic interpreted systems fuzzy computation tree logic transformation algorithm
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Hierarchical Resource Load Balancing Based on Multi-Agent in ServiceBSP Model
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作者 Bin CHENG Yan JIANG Weiqin TONG 《International Journal of Communications, Network and System Sciences》 2010年第1期59-65,共7页
Based on ServiceBSP model, a hierarchical resource load balancing algorithm with Multi-Agent is put forward in this paper which achieves the goal of dynamic load balancing and favorable Fault-tolerant. The algorithm c... Based on ServiceBSP model, a hierarchical resource load balancing algorithm with Multi-Agent is put forward in this paper which achieves the goal of dynamic load balancing and favorable Fault-tolerant. The algorithm calculates the load value according to the attributes of resource and scheduling tasks relies on the load value, while updating the load information dynamically depending on Multi-Agent. The method avoids frequent communications on load information. Furthermore, the paper introduces the function of agents, relations and communications among agents in details. Finally, by comparing response time and distribution of load using proposed method with other available methods such as without no load balancing and load balancing only giving regards to CPU, the experimental simulation shows that the load balancing based on Multi-Agent possesses superior performance on response time and load balancing. 展开更多
关键词 ServiceBSP model multi-agent LOAD Balancing
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A model for knowledge transfer in a multi-agent organization based on lattice kinetic model
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作者 WU Weiwei MA Qian +1 位作者 LIU Yexin KIM Yongjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期156-167,共12页
A study on knowledge transfer in a mutli-agent organization is performed by applying the basic principle in physics such as the kinetic theory.Based on the theoretical analysis of the knowledge accumulation process an... A study on knowledge transfer in a mutli-agent organization is performed by applying the basic principle in physics such as the kinetic theory.Based on the theoretical analysis of the knowledge accumulation process and knowledge transfer attributes,a special type of knowledge field(KF)is introduced and the knowledge diffusion equation(KDE)is developed.The evolution of knowledge potential is modeled by lattice kinetic equation and verified by numerical experiments.The new equation-based modeling developed in this paper is meaningful to simulate and predict the knowledge transfer process in firms.The development of the lattice kinetic model(LKM)for knowledge transfer can contribute to the knowledge management theory,and the managers can also simulate the knowledge accumulation process by using the LKM. 展开更多
关键词 knowledge transfer multi-agent system knowledge field(KF) lattice kinetic model(LKM) knowledge diffusion equation(KDE)
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A Fundamental Study on Multi-agent Pedestrian Model Based on Risk Avoidance Behavior during Road Blockage and Evacuation Simulation of Regional Urban Disaster
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作者 Hideaki Takayanagi Tatsuto Kihara +5 位作者 Yosuke Kurita Kazuhide Kawaguchi Hidetoshi Kawaguchi Takaaki Furukawa Takuhi Ono Shogo Yamada 《Journal of Civil Engineering and Architecture》 2019年第4期219-237,共19页
Regional cities in Japan are at the risk of experiencing big fire accidents or earthquakes every day.However,neither the number nor the capacity of shelters has increased because local governments might not consider t... Regional cities in Japan are at the risk of experiencing big fire accidents or earthquakes every day.However,neither the number nor the capacity of shelters has increased because local governments might not consider them owing to budget shortfall.By contrast,wide-area evacuation simulations can easily provide an antagonizing image of regional urban disasters.After a disaster,the city collapses and the evacuation routes are closed;consequently,evacuees feel anxious and they cannot move as usual.This anxiety behavior has not been considered in previous related studies and simulations.In this study,a wide-area evacuation simulation is developed;this model can not only calculate the possibility of blocking escape routes when the city is broken but also provide safe and more realistic evacuation plans before a disaster occurs by incorporating into the simulation the risk avoidance behaviors of evacuees from road blockage,such as“the route re-seeking behavior”and“the shelter re-selecting behavior”. 展开更多
关键词 Wide-area EVACUATION simulation multi-agent model risk AVOIDANCE BEHAVIOR regional DISASTER prevention plan
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Timed-Automata Based Model-Checking of a Multi-Agent System: A Case Study
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作者 Nadeem Akhtar Muhammad Nauman 《Journal of Software Engineering and Applications》 2015年第2期43-50,共8页
A multi-agent based transport system is modeled by timed automata model extended with clock variables. The correctness properties of safety and liveness of this model are verified by timed automata based UPPAAL. Agent... A multi-agent based transport system is modeled by timed automata model extended with clock variables. The correctness properties of safety and liveness of this model are verified by timed automata based UPPAAL. Agents have a degree of control on their own actions, have their own threads of control, and under some circumstances they are also able to take decisions. Therefore they are autonomous. The multi-agent system is modeled as a network of timed automata based agents supported by clock variables. The representation of agent requirements based on mathematics is helpful in precise and unambiguous specifications, thereby ensuring correctness. This formal representation of requirements provides a way for logical reasoning about the artifacts produced. We can be systematic and precise in assessing correctness by rigorously specifying the functional requirements. 展开更多
关键词 Software CORRECTNESS FORMAL Verification model CHECKING Timed-Automata multi-agent System TIMED Computation Tree Logic (TCTL)
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Supply Chain Management System Model of Virtual Enterprises Based on Multi-Agent
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作者 LI Zhen ZHANG Pei-pei 《International Journal of Plant Engineering and Management》 2008年第3期167-173,共7页
Based on the analysis of a virtual enterprise and the development of supply chain management, their integration is proposed. Then, the difference between multi-agent system modeling method and the traditional modeling... Based on the analysis of a virtual enterprise and the development of supply chain management, their integration is proposed. Then, the difference between multi-agent system modeling method and the traditional modeling method is analyzed, and a method based on Java agent framework for multi-agent systems( JAFMAS) is proposed. By using this method the virtual enterprise' s supply chain management system model is established. 展开更多
关键词 virtual enterprise supply chain management multi-agent JAFMAS system model
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LLMKB:Large Language Models with Knowledge Base Augmentation for Conversational Recommendation
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作者 FANG Xiu QIU Sijia +1 位作者 SUN Guohao LU Jinhu 《Journal of Donghua University(English Edition)》 2026年第1期91-103,共13页
Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstan... Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstanding performance across various domains,thereby prompting researchers to investigate their applicability in recommendation systems.However,due to the lack of task-specific knowledge and an inefficient feature extraction process,LLMs still have suboptimal performance in recommendation tasks.Therefore,external knowledge sources,such as knowledge graphs(KGs)and knowledge bases(KBs),are often introduced to address the issue of data sparsity.Compared to KGs,KBs possess higher retrieval efficiency,making them more suitable for scenarios where LLMs serve as recommenders.To this end,we introduce a novel framework integrating LLMs with KBs for enhanced retrieval generation,namely LLMKB.LLMKB initially leverages structured knowledge to create mapping dictionaries,extracting entity-relation information from heterogeneous knowledge to construct KBs.Then,LLMKB achieves the embedding calibration between user information representations and documents in KBs through retrieval model fine-tuning.Finally,LLMKB employs retrievalaugmented generation to produce recommendations based on fused text inputs,followed by post-processing.Experiment results on two public CRS datasets demonstrate the effectiveness of our framework.Our code is publicly available at the link:https://anonymous.4open.science/r/LLMKB-6FD0. 展开更多
关键词 recommender system large language model(LLM) knowledge base(KB)
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Towards mechanism-based tau-targeted therapies
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作者 Lidia Bakota Roland Brandt 《Neural Regeneration Research》 2026年第2期687-688,共2页
Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,ta... Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies. 展开更多
关键词 tau targeted therapies cellular components mechanism based therapies cellular componentswhich cellular models MICROTUBULES TAUOPATHIES neurodegenerative diseasescollectively
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Koopman-Based Robust Model Predictive Control With Online Identification for Nonlinear Dynamical Systems
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作者 Ruiqi Ke Jingchuan Tang +1 位作者 Zongyu Zuo Yan Shi 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1947-1949,共3页
Dear Editor,This letter presents a novel approach to the data-driven control of unknown nonlinear systems.By leveraging online sparse identification based on the Koopman operator,a high-dimensional linear system model... Dear Editor,This letter presents a novel approach to the data-driven control of unknown nonlinear systems.By leveraging online sparse identification based on the Koopman operator,a high-dimensional linear system model approximating the actual system is obtained online.The upper bound of the discrepancy between the identified model and the actual system is estimated using real-time prediction error,which is then utilized in the design of a tube-based robust model predictive controller.The effectiveness of the proposed approach is validated by numerical simulation. 展开更多
关键词 koopman operatora online identification tube based control real time prediction error online sparse identification identified model Koopman based control robust model predictive control
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Modeling of the Mechanical Properties of Blend Based Polymer Nanocomposites Considering the Effects of Janus Nanoparticles on Polymer/Polymer Interface 被引量:5
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作者 Esmail Sharifzadeh 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第2期164-177,共14页
Blend based polymer nanocomposites, comprising Janus nanoparticles at their polymer/polymer interface, were analytically/experimentally evaluated. The modeling procedure was performed in two stages: first, modeling of... Blend based polymer nanocomposites, comprising Janus nanoparticles at their polymer/polymer interface, were analytically/experimentally evaluated. The modeling procedure was performed in two stages: first, modeling of polymer/polymer interface region comprising Janus nanoparticles and second, modeling of the entire systems as a function of the variation of the blend morphology.In the first stage, the modeling procedure was performed based on the development of the model proposed by Ji et al. and in the second stage, the fundamental of Kolarik's model was used in order to propose a developed and more practical model. It was shown that Janus nanoparticles may form dual polymer/particle interphase at polymer/polymer interface which can drastically affect the final mechanical properties of the system. Comparing the results of tensile tests imposed on different prepared samples with the predictions of the model proved its accuracy and reliability(error < 9%). 展开更多
关键词 BLEND based POLYMER nanocomposites JANUS NANOPARTICLES modeling of MECHANICAL properties
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A criterion for selecting the appropriate one from the trained models for model-based offline policy evaluation
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作者 Chongchong Li Yue Wang +1 位作者 Zhi-Ming Ma Yuting Liu 《CAAI Transactions on Intelligence Technology》 2025年第1期223-234,共12页
Offline policy evaluation,evaluating and selecting complex policies for decision-making by only using offline datasets is important in reinforcement learning.At present,the model-based offline policy evaluation(MBOPE)... Offline policy evaluation,evaluating and selecting complex policies for decision-making by only using offline datasets is important in reinforcement learning.At present,the model-based offline policy evaluation(MBOPE)is widely welcomed because of its easy to implement and good performance.MBOPE directly approximates the unknown value of a given policy using the Monte Carlo method given the estimated transition and reward functions of the environment.Usually,multiple models are trained,and then one of them is selected to be used.However,a challenge remains in selecting an appropriate model from those trained for further use.The authors first analyse the upper bound of the difference between the approximated value and the unknown true value.Theoretical results show that this difference is related to the trajectories generated by the given policy on the learnt model and the prediction error of the transition and reward functions at these generated data points.Based on the theoretical results,a new criterion is proposed to tell which trained model is better suited for evaluating the given policy.At last,the effectiveness of the proposed criterion is demonstrated on both benchmark and synthetic offline datasets. 展开更多
关键词 offline policy evaluation reinforcement learning model based
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Preliminary Design and Application of a Longitudinal Trajectory Model for Prognosis of Intracerebral Hemorrhage Based on Blood Urea Nitrogen Characteristics
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作者 GUO Dong-bin QI Xiao-long HUANG Jun-long 《Chinese Journal of Biomedical Engineering(English Edition)》 2025年第3期118-124,共7页
Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH pati... Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH patients admitted to our hospital between 2020 and 2024 were collected,including demographic information,National Institutes of Health Stroke Scale(NIHSS)scores at admission,dynamic changes in BUN levels during treatment,and 30-day survival outcomes.A latent class growth model(LCGM)was first used for preliminary modeling,followed by a latent growth mixture modeling(GMM)approach to determine the final model.Three classes of BUN trajectories for ICH prognosis were identified,and latent classes were established.GMM modeling was then performed on these latent classes,considering linear,quadratic,and cubic polynomial forms;six GMM models were constructed and individuals were assigned to latent trajectory groups for validation.Results:LCGM analysis ultimately identified three dynamic BUN trajectory groups:Sustained low-level group(76 cases,23.8%):BUN remained stable between 3.1-9.0 mmol/L,with the highest 30-day survival rate(98.7%).Fluctuating-declining group(222 cases,69.4%):BUN initially increased and then slowly decreased(peak at day 3:15.2 mmol/L),with a 30-day mortality of 8.1%(18/222),higher than the sustained low-level group.Sustained high-level group(22 cases,6.9%):BUN mean>9.0 mmol/L,with a 30-day mortality of 41.7%(P=0.000).GMM model fitting showed that the cubic polynomial GMM model was optimal(AIC=6754.474,BIC=6852.450,Entropy=0.905).Incorporating gender,age,and BMI as covariates revealed significant effects for gender(Estimate=0.045,-0.011,P=0.000,0.000).The AUC for predicting 30-day mortality was 0.88(sensitivity 82.8%,specificity 77.9%),which increased to 0.89 when combined with admission NIHSS scores.Conclusion:The LCGM+GMM model based on dynamic BUN trajectories effectively distinguishes prognostic subgroups in ICH patients.Patients with persistently elevated or fluctuating-rising BUN levels have a significantly higher mortality risk compared to those with sustained low levels.This model provides a new quantitative tool for early identification of high-risk patients and poor prognoses. 展开更多
关键词 Blood urea nitrogen construct apply longitudinal trajectory model intracerebral hemorrhage ich based Longitudinal trajectory model Intracerebral hemorrhage Latent growth mixture modeling PROGNOSIS latent class growth model lcgm
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A Feature-Based Parametric Product Modeling System in CIMS Environment 被引量:4
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作者 李海龙 《High Technology Letters》 EI CAS 1997年第1期13-16,共4页
This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the charact... This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM. 展开更多
关键词 CIMS FEATURE based modeling PARAMETRIC design PRODUCT model OODB
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