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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3D culture model drug screening
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An integrated method of data-driven and mechanism models for formation evaluation with logs 被引量:1
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作者 Meng-Lu Kang Jun Zhou +4 位作者 Juan Zhang Li-Zhi Xiao Guang-Zhi Liao Rong-Bo Shao Gang Luo 《Petroleum Science》 2025年第3期1110-1124,共15页
We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpr... We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpreting these parameters is crucial for effectively exploring and developing oil and gas.However,with the increasing complexity of geological conditions in this industry,there is a growing demand for improved accuracy in reservoir parameter prediction,leading to higher costs associated with manual interpretation.The conventional logging interpretation methods rely on empirical relationships between logging data and reservoir parameters,which suffer from low interpretation efficiency,intense subjectivity,and suitability for ideal conditions.The application of artificial intelligence in the interpretation of logging data provides a new solution to the problems existing in traditional methods.It is expected to improve the accuracy and efficiency of the interpretation.If large and high-quality datasets exist,data-driven models can reveal relationships of arbitrary complexity.Nevertheless,constructing sufficiently large logging datasets with reliable labels remains challenging,making it difficult to apply data-driven models effectively in logging data interpretation.Furthermore,data-driven models often act as“black boxes”without explaining their predictions or ensuring compliance with primary physical constraints.This paper proposes a machine learning method with strong physical constraints by integrating mechanism and data-driven models.Prior knowledge of logging data interpretation is embedded into machine learning regarding network structure,loss function,and optimization algorithm.We employ the Physically Informed Auto-Encoder(PIAE)to predict porosity and water saturation,which can be trained without labeled reservoir parameters using self-supervised learning techniques.This approach effectively achieves automated interpretation and facilitates generalization across diverse datasets. 展开更多
关键词 Well log Reservoir evaluation Label scarcity Mechanism model Data-driven model Physically informed model Self-supervised learning Machine learning
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A Study on the Postgraduate Quality Evaluation Model and Its Recognition Analysis
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作者 Peng Xu Xinyuan Liu Yuzhu Hu 《Journal of Contemporary Educational Research》 2025年第7期158-168,共11页
With the rapid development of generative artificial intelligence technologies,represented by large language models,university-level computer science education is undergoing a critical transition-from knowledge-based i... With the rapid development of generative artificial intelligence technologies,represented by large language models,university-level computer science education is undergoing a critical transition-from knowledge-based instruction to competency-oriented teaching.A postgraduate student competency evaluation model can serve as a framework to organize and guide both teaching and research activities at the postgraduate level.A number of relevant research efforts have already been conducted in this area.Graduate education plays a vital role not only as a continuation and enhancement of undergraduate education but also as essential preparation for future research endeavors.An analysis of the acceptance of competency evaluation models refers to the assessment of how various stakeholders perceive the importance of different components within the model.Investigating the degree of acceptance among diverse groups-such as current undergraduate students,current postgraduate students,graduates with less than three years of work experience,and those with more than three years of work experience-can offer valuable insights for improving and optimizing postgraduate education and training practices. 展开更多
关键词 POSTGRADUATE Quality evaluation model IMPORTANCE Recognition analysis
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Application Value Analysis of a New Empowerment Teaching Method Based on Kirkpatrick’s Evaluation Model in Teaching Chinese Medicine Nursing in Otorhinolaryngology
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作者 Xia Zhang Yue Xu 《Journal of Clinical and Nursing Research》 2025年第6期305-311,共7页
Objective:To explore the application value of a new empowerment teaching method based on Kirkpatrick’s evaluation model in teaching Chinese medicine nursing in otorhinolaryngology.Methods:60 nurses who practiced in t... Objective:To explore the application value of a new empowerment teaching method based on Kirkpatrick’s evaluation model in teaching Chinese medicine nursing in otorhinolaryngology.Methods:60 nurses who practiced in the otolaryngology department of our hospital from June 2022 to October 2024 were included in the study and equally divided into two groups using a convenient sampling method.30 nurses who chose traditional Chinese medicine skill teaching management were included in the control group,and 30 nurses who chose the new empowerment teaching method based on Kirkpatrick’s evaluation model were included in the observation group.Relevant indicators such as clinical teaching environment perception,theoretical knowledge scores of Chinese medicine nursing,and excellent rate of practical operation assessment were compared.Results:The nurses in the observation group had higher scores for clinical teaching environment perception than the control group(P<0.05).However,the midterm and final exam scores for theoretical knowledge of Chinese medicine nursing were higher in the observation group than in the control group(P<0.05).Compared with the control group,the observation group had a higher excellent rate of practical operation assessment(93.33%>73.33%)and a higher Chinese medicine nursing ability score[(215.69±19.73)points>(184.87±15.66)points](P<0.05).Conclusion:Applying the new empowerment teaching method based on Kirkpatrick’s evaluation model to Chinese medicine nursing teaching in otolaryngology can help nurses understand the theoretical knowledge of Chinese medicine nursing and optimize the clinical teaching environment,thereby promoting their practical skills and Chinese medicine nursing abilities. 展开更多
关键词 Kirkpatrick evaluation model New empowerment teaching method Otolaryngology Chinese medicine nursing
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Application Effect of Problem-Based Learning Combined with DOPS Evaluation Model in Standardized Nurse Training
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作者 Wenjun Liang 《Journal of Clinical and Nursing Research》 2025年第9期231-236,共6页
With the continuous development of the nursing discipline,standardized nurse training has always been a crucial link in the development of nursing science and plays an irreplaceable role in talent cultivation.However,... With the continuous development of the nursing discipline,standardized nurse training has always been a crucial link in the development of nursing science and plays an irreplaceable role in talent cultivation.However,in the current standardized training for some nurses,there are problems such as the simplification of nursing skill evaluation models and insufficient post competence of nurses.Therefore,optimizing the training model for nursing talents has become an inevitable measure.The problem-based learning(PBL)method and the Direct Observation of Procedural Skills(DOPS)evaluation model provide new directions and guidance for the development of training.Against this background,this paper explores effective approaches for standardized nurse training,starting from basic concepts and gradually delving into specific practical paths,aiming to improve the quality of talent cultivation and provide valuable references for other researchers. 展开更多
关键词 Problem-oriented DOPS evaluation model Standardized nurse training
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Research on the Evaluation Model of Software Talent Cultivation Based on Multivariant Data Fusion
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作者 Yin Chen Haoxuan Tang +4 位作者 Lei Zhang Tonghua Su Zhongjie Wang Ruihan Hu Shanli Xie 《计算机教育》 2025年第3期130-137,共8页
This paper proposes a multivariate data fusion based quality evaluation model for software talent cultivation.The model constructs a comprehensive ability and quality evaluation index system for college students from ... This paper proposes a multivariate data fusion based quality evaluation model for software talent cultivation.The model constructs a comprehensive ability and quality evaluation index system for college students from a perspective of engineering course,especially of software engineering.As for evaluation method,relying on the behavioral data of students during their school years,we aim to construct the evaluation model as objective as possible,effectively weakening the negative impact of personal subjective assumptions on the evaluation results. 展开更多
关键词 Quality evaluation model Software talent cultivation Behavioral data
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Rat models of frozen shoulder:Classification and evaluation 被引量:1
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作者 Hezirui Gu Wenqing Xie +2 位作者 Hengzhen Li Shuguang Liu Yusheng Li 《Animal Models and Experimental Medicine》 2025年第1期92-101,共10页
Frozen shoulder(FS),also known as adhesive capsulitis,is a condition that causes contraction and stiffness of the shoulder joint capsule.The main symptoms are per-sistent shoulder pain and a limited range of motion in... Frozen shoulder(FS),also known as adhesive capsulitis,is a condition that causes contraction and stiffness of the shoulder joint capsule.The main symptoms are per-sistent shoulder pain and a limited range of motion in all directions.These symp-toms and poor prognosis affect people's physical health and quality of life.Currently,the specific mechanisms of FS remain unclear,and there is variability in treatment methods and their efficacy.Additionally,the early symptoms of FS are difficult to distinguish from those of other shoulder diseases,complicating early diagnosis and treatment.Therefore,it is necessary to develop and utilize animal models to under-stand the pathogenesis of FS and to explore treatment strategies,providing insights into the prevention and treatment of human FS.This paper reviews the rat models available for FS research,including external immobilization models,surgical internal immobilization models,injection modeling models,and endocrine modeling models.It introduces the basic procedures for these models and compares and analyzes the advantages,disadvantages,and applicability of each modeling method.Finally,our paper summarizes the common methods for evaluating FS rat models. 展开更多
关键词 endocrine modeling INJECTION rat model surgical internal immobilization
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Geological-engineering comprehensive evaluation model and application of feasibility of hydraulic fracturing in hydrate-bearing sediments 被引量:1
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作者 Tian-Kui Guo Lin-Rui Xue +5 位作者 Ming Chen Bo Zhang Zhen-Tao Li Wen-Jie Huang Xiao-Qiang Liu Zhan-Qing Qu 《Petroleum Science》 2025年第3期1140-1154,共15页
Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides ne... Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides new approaches to enhance hydrate development effectiveness.Addressing the current lack of quantitative and objective methods for evaluating the fracability of hydrate reservoirs,this study clarifies the relationship between geological and engineering fracability and proposes a comprehensive evaluation model for hydrate reservoir fracability based on grey relational analysis and the criteria importance through intercriteria correlation method.By integrating results from hydraulic fracturing experiments on hydrate sediments,the fracability of hydrate reservoirs is assessed.The concept of critical construction parameter curves for hydrate reservoirs is introduced for the first time.Additionally,two-dimensional fracability index evaluation charts and three-dimensional fracability construction condition discrimination charts are established.The results indicate that as the comprehensive fracability index increases,the feasibility of forming fractures in hydrate reservoirs improves,and the required normalized fracturing construction parameters gradually decrease.The accuracy rate of the charts in judging experimental results reached 89.74%,enabling quick evaluations of whether hydrate reservoirs are worth fracturing,easy to fracture,and capable of being fractured.This has significant engineering implications forthehydraulicfracturingof hydratereservoirs. 展开更多
关键词 Hydraulic fracturing HYDRATES Fracability evaluation Comprehensive fracability index Fracability chart
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An enhanced stability evaluation system for entry-type excavations:Utilizing a hybrid bagging-SVM model,GP and kriging techniques 被引量:1
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作者 Shuai Huang Jian Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2360-2373,共14页
In underground mining,especially in entry-type excavations,the instability of surrounding rock structures can lead to incalculable losses.As a crucial tool for stability analysis in entry-type excavations,the critical... In underground mining,especially in entry-type excavations,the instability of surrounding rock structures can lead to incalculable losses.As a crucial tool for stability analysis in entry-type excavations,the critical span graph must be updated to meet more stringent engineering requirements.Given this,this study introduces the support vector machine(SVM),along with multiple ensemble(bagging,adaptive boosting,and stacking)and optimization(Harris hawks optimization(HHO),cuckoo search(CS))techniques,to overcome the limitations of the traditional methods.The analysis indicates that the hybrid model combining SVM,bagging,and CS strategies has a good prediction performance,and its test accuracy reaches 0.86.Furthermore,the partition scheme of the critical span graph is adjusted based on the CS-BSVM model and 399 cases.Compared with previous empirical or semi-empirical methods,the new model overcomes the interference of subjective factors and possesses higher interpretability.Since relying solely on one technology cannot ensure prediction credibility,this study further introduces genetic programming(GP)and kriging interpolation techniques.The explicit expressions derived through GP can offer the stability probability value,and the kriging technique can provide interpolated definitions for two new subclasses.Finally,a prediction platform is developed based on the above three approaches,which can rapidly provide engineering feedback. 展开更多
关键词 Entry-type excavations Critical span graph Stability evaluation Machine learning Support vector machine
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Calculation model for kinetic energy and rock burst risk evaluation method during roadway excavation 被引量:1
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作者 Yunliang Tan Yan Tan +5 位作者 Weiyao Guo Bo Li Shudong He Lei Zhang Yujiang Zhang Qiuyuan Zhang 《International Journal of Mining Science and Technology》 2025年第5期677-690,共14页
The accumulation and release of deformation energy within the rock mass of a roadway are primary contributors to the occurrence of rock bursts.This study introduces a calculation model for the kinetic energy generated... The accumulation and release of deformation energy within the rock mass of a roadway are primary contributors to the occurrence of rock bursts.This study introduces a calculation model for the kinetic energy generated during roadway excavation,which is based on the fracture and energy states of the rock mass.The relationships among the mining depth,width of the plastic zone,rebound range of the roof and floor,stress concentration factor,and the induced kinetic energy are systematically explored.Furthermore,a rock burst risk evaluation method is proposed.The findings indicate that the energy evolution of the rock mass can be categorized into four stages:energy accumulation due to in-situ stress,energy accumulation resulting from coal compression,energy dissipation through coal plastic deformation,and energy consumption due to coal failure.The energy release from the rock mass is influenced by several factors,including mining depth,stress concentration factor,the width of the plastic zone,and the rebound range of the roof and floor.Within the plastic zone of coal,the energy released per unit volume of coal and the induced kinetic energy exhibit a nonlinear increase with mining depth and stress concentration factor,while they decrease linearly as the width of the plastic zone increases.Similarly,the driving energy per unit volume of the roof and floor shows a nonlinear increase with mining depth and stress concentration factor,a linear increase with the rebound range of the roof and floor,and a linear decrease with the width of the plastic zone.A rock burst risk evaluation method is developed based on the kinetic energy model.Field observations demonstrate that this method aligns with the drilling cuttings rock burst risk assessment method,thereby confirming its validity. 展开更多
关键词 Roadway rock mass Kinetic energy Rock burst Rock burst risk evaluation Roof and floor rebound
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Application Research of Acute Skin Injury Model in Soothing Efficacy Evaluation
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作者 Li Jing Wu Mingcheng +3 位作者 Wu Lishi Shi Xuedong Zhou Panfeng He Jitian 《China Detergent & Cosmetics》 2025年第1期22-26,共5页
An acute skin injury model using continuous tape tearing was established,and studies the application of this model in the evaluation of soothing effects through instrument evaluation.30 healthy adult subjects were sel... An acute skin injury model using continuous tape tearing was established,and studies the application of this model in the evaluation of soothing effects through instrument evaluation.30 healthy adult subjects were selected as the research subjects,and an acute skin model was established on the forearm flexion side of the subjects.The skin color a^(*)value and transdermal water loss rate(TEWL)value of the blank and experimental groups were tested using instruments.The results showed that at 15 and 30 minutes after using the sample,the growth values of a^(*)value and TEWL value in the experimental group were significantly lower than those in the blank group(P<0.05),the acute skin lesion model can effectively evaluate the soothing effect of cosmetics. 展开更多
关键词 soothing model efficacy evaluation COSMETIC
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Evaluation Model for Energy Efficiency of Factory Workshop Based on DSR and Fuzzy Borda
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作者 Shengjie Yang Zijian Zhu Xu Ouyang 《Energy Engineering》 2025年第3期1073-1092,共20页
In the context of advancing towards dual carbon goals,numerous factories are actively engaging in energy efficiency upgrades and transformations.To accurately pinpoint energy efficiency bottlenecks within factories an... In the context of advancing towards dual carbon goals,numerous factories are actively engaging in energy efficiency upgrades and transformations.To accurately pinpoint energy efficiency bottlenecks within factories and prioritize renovation sequences,it is crucial to conduct comprehensive evaluations of the energy performance across various workshops.Therefore,this paper proposes an evaluation model for workshop energy efficiency based on the drive-state-response(DSR)framework combined with the fuzzy BORDA method.Firstly,an in-depth analysis of the relationships between different energy efficiency indicators was conducted.Based on the DSR model,evaluation criteria were selected from three dimensions-drive factors,state characteristics,and response measures-to establish a robust energy efficiency indicator system.Secondly,three distinct assessment techniques were selected:Grey Relational Analysis(GRA),Entropy Weight Method(EWM),and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)forming a diversified set of evaluation methods.Subsequently,by introducing the fuzzy BORDA method,a comprehensive energy efficiency evaluation model was developed,aimed at quantitatively ranking the energy performance status of each workshop.Using a real-world factory as a case study,applying our proposed evaluationmodel yielded detailed scores and rankings for each workshop.Furthermore,post hoc testing was performed using the Spearman correlation coefficient,revealing a statistic value of 10.209,which validates the effectiveness and reliability of the proposed evaluation model.This model not only assists in identifying underperforming workshops within the factory but also provides solid data support and a decision-making basis for future energy efficiency optimization strategies. 展开更多
关键词 DSR model fuzzy Borda method combined evaluation energy efficiency evaluation
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Calibration and evaluation of MET models for estimating energy expenditure using thigh and ankle-worn move 4 accelerometer
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作者 Marco Giurgiu Eni Hysenllari +2 位作者 Jörg Ottenbacher Ulrich Ebner-Priemer Irina Timm 《Translational Exercise Biomedicine》 2025年第4期315-325,共11页
Objectives:Valid estimation of energy expenditure remains a challenge,particularly when using ankle-and thighworn devices.The Move 4 is a research-grade accelerometer previously tested for predicting metabolic equival... Objectives:Valid estimation of energy expenditure remains a challenge,particularly when using ankle-and thighworn devices.The Move 4 is a research-grade accelerometer previously tested for predicting metabolic equivalents(METs)when worn at the waist or wrist.This study aimed to calibrate and evaluate regression models to estimate METs from Move 4 data when worn at the ankle and thigh.Methods:Participants completed walking and jogging tasks under laboratory conditions while wearing Move 4 sensors and with indirect calorimetry as a reference measure.Models were calibrated using study 1(n=160)and evaluated in an independent dataset(study 2;n=15).Performance was assessed using mean absolute error(MAE),root mean square error(RMSE),and Bland-Altman analyses.Results:The MET models demonstrated strong agreement across both locations and datasets.For the thigh position,the MAE ranged from 0.60 METs(walking)to 1.38 METs(jogging),with RMSE of 0.82 and 1.70 in the evaluation data.Calibration metrics were comparable(jogging:MAE=1.24,RMSE=1.63).The ankle models showed similar accuracy,with MAEs of 0.66(walking)and 1.39(jogging),and RMSEs of 0.85 and 1.67,respectively.Systematic bias remained low(mean differences between−0.34 and−0.01 METs).Conclusions:This study provides the first calibration and evaluation for estimating METs from ankle-and thigh-worn Move 4 accelerometers.The model indicated accurate,highresolution MET estimation for walking and jogging.Future work should expand independent performance evaluations,including diverse activities such as static activities,and diverse samples under free-living conditions. 展开更多
关键词 validation evaluation ACCELEROMETER sensor energy expenditure model performance
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Modeling and Performance Evaluation of Streaming Data Processing System in IoT Architecture
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作者 Feng Zhu Kailin Wu Jie Ding 《Computers, Materials & Continua》 2025年第5期2573-2598,共26页
With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Alth... With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Although distributed streaming data processing frameworks such asApache Flink andApache Spark Streaming provide solutions,meeting stringent response time requirements while ensuring high throughput and resource utilization remains an urgent problem.To address this,the study proposes a formal modeling approach based on Performance Evaluation Process Algebra(PEPA),which abstracts the core components and interactions of cloud-based distributed streaming data processing systems.Additionally,a generic service flow generation algorithmis introduced,enabling the automatic extraction of service flows fromthe PEPAmodel and the computation of key performance metrics,including response time,throughput,and resource utilization.The novelty of this work lies in the integration of PEPA-based formal modeling with the service flow generation algorithm,bridging the gap between formal modeling and practical performance evaluation for IoT systems.Simulation experiments demonstrate that optimizing the execution efficiency of components can significantly improve system performance.For instance,increasing the task execution rate from 10 to 100 improves system performance by 9.53%,while further increasing it to 200 results in a 21.58%improvement.However,diminishing returns are observed when the execution rate reaches 500,with only a 0.42%gain.Similarly,increasing the number of TaskManagers from 10 to 20 improves response time by 18.49%,but the improvement slows to 6.06% when increasing from 20 to 50,highlighting the importance of co-optimizing component efficiency and resource management to achieve substantial performance gains.This study provides a systematic framework for analyzing and optimizing the performance of IoT systems for large-scale real-time streaming data processing.The proposed approach not only identifies performance bottlenecks but also offers insights into improving system efficiency under different configurations and workloads. 展开更多
关键词 System modeling performance evaluation streaming data process IoT system PEPA
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Stiffness Modeling and Performance Evaluation of a(R(RPS&RP))&2-UPS Parallel Mechanism
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作者 Minghao Wang Manxin Wang +1 位作者 Hutian Feng Chuhan Wu 《Chinese Journal of Mechanical Engineering》 2025年第5期590-610,共21页
The average stiffness performance indices throughout the workspace are commonly used as global stiffness performance indices to evaluate the overall stiffness performance of parallel mechanisms,which involves an analy... The average stiffness performance indices throughout the workspace are commonly used as global stiffness performance indices to evaluate the overall stiffness performance of parallel mechanisms,which involves an analysis of the stiffness performance of numerous discrete points in the workspace.This necessitates time-consuming and inefficient calculation,which is particularly pronounced in the optimization design stage of the mechanism,where the variations in the global stiffness performance indices versus various dimensional and structural parameters need to be analyzed.This paper presents a semi-analytical approach for stiffness modeling of the novel(R(RPS&RP))&2-UPS parallel mechanism(referred to as the Trifree mechanism)and proposes“local”stiffness performance indices as alternatives to global indices.Drawing on the screw theory,the Cartesian stiffness matrix of the Trifree mechanism is formulated explicitly by considering the compliances of all elastic elements and the over-constraint characteristics inherent in the mechanism.Based on the spherical motion pattern of the Trifree mechanism,four special reference configurations are extracted within the workspace.This yields“local”stiffness performance indices capable of accurately evaluating the overall stiffness performance of the mechanism and effectively improving the computational efficiency.The variations in global and“local”stiffness performance indices versus key design parameters are investigated.Furthermore,the proposed indices are applied to the Tricept and Trimule mechanisms.The results demonstrate that the proposed indices exhibit excellent computational accuracy and efficiency in evaluating the overall stiffness performance of these spherical parallel mechanisms.Moreover,the stiffness performance of the novel parallel mechanism investigated in this study closely resembles that of the well-known Tricept and Trimule mechanisms.This research proposes a semi-analytic stiffness model of the Trifree mechanism and“local”stiffness performance indices to evaluate the overall stiffness performance,thereby substantially improving the computational efficiency without sacrificing accuracy. 展开更多
关键词 Parallel mechanism Stiffness modeling Performance evaluation
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Neural Architecture Search via Hierarchical Evaluation of Surrogate Models
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作者 Xiaofeng Liu Yubin Bao Fangling Leng 《Computers, Materials & Continua》 2025年第8期3503-3517,共15页
The rapid development of evolutionary deep learning has led to the emergence of various Neural Architecture Search(NAS)algorithms designed to optimize neural network structures.However,these algorithms often face sign... The rapid development of evolutionary deep learning has led to the emergence of various Neural Architecture Search(NAS)algorithms designed to optimize neural network structures.However,these algorithms often face significant computational costs due to the time-consuming process of training neural networks and evaluating their performance.Traditional NAS approaches,which rely on exhaustive evaluations and large training datasets,are inefficient for solving complex image classification tasks within limited time frames.To address these challenges,this paper proposes a novel NAS algorithm that integrates a hierarchical evaluation strategy based on Surrogate models,specifically using supernet to pre-trainweights and randomforests as performance predictors.This hierarchical framework combines rapid Surrogate model evaluations with traditional,precise evaluations to balance the trade-off between performance accuracy and computational efficiency.The algorithm significantly reduces the time required for model evaluation by predicting the fitness of candidate architectures using a random forest Surrogate model,thus alleviating the need for full training cycles for each architecture.The proposed method also incorporates evolutionary operations such as mutation and crossover to refine the search process and improve the accuracy of the resulting architectures.Experimental evaluations on the CIFAR-10 and CIFAR-100 datasets demonstrate that the proposed hierarchical evaluation strategy reduces the search time and costs compared to traditional methods,while achieving comparable or even superior model performance.The results suggest that this approach can efficiently handle resourceconstrained tasks,providing a promising solution for accelerating the NAS process without compromising the quality of the generated architectures. 展开更多
关键词 Neural architecture search hierarchical evaluation image classification Surrogate model
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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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Comprehensive status evaluation and prediction of blast furnace based on cascade system and combined model
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作者 Zhen Zhang Jue Tang +3 位作者 Quan Shi Mansheng Chu Mingyu Wang Zhifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第12期2942-2957,共16页
The comprehensive status of blast furnaces was one of the most important factors affecting their economy,quality,and longev-ity.The blast furnace comprehensive status had the nature of“black box,”and it was“unpredi... The comprehensive status of blast furnaces was one of the most important factors affecting their economy,quality,and longev-ity.The blast furnace comprehensive status had the nature of“black box,”and it was“unpredictable.”In this study,a blast furnace com-prehensive status score and prediction method based on a cascade system and a combined model were proposed to address this issue.A dual cascade evaluation system was developed by integrating subjective and objective weighting methods.The analytic hierarchy process,coefficient of variation,entropy weight method,and impart combinatorial games were jointly employed to determine the optimal weight distribution across indicators.Categorized statuses(raw material,gas flow,furnace body,furnace cylinder,and iron-slag)were evaluated.Based on the five categories of the status data,the second cascade was applied to upgrade the quantitative evaluation of the comprehens-ive status.The weights of the different categories were 0.22,0.15,0.22,0.21,and 0.20,respectively.According to the data analysis,the results of the comprehensive status score closely matched the on-site production logs.Based on the blast furnace smelting period,the maximal information coefficient method was applied to the 100 parameters that were most relevant to the comprehensive status.A com-bined prediction model for a comprehensive status score was designed using bidirectional long short-term memory(BiLSTM)and categorical boosting(CatBoost).The test results indicated that the combined model reduced the mean absolute error by an average of 0.275 and increased the hit rate by an average of 5.65 percentage points compared to BiLSTM or CatBoost alone.When the er-ror range was±2.5,the combined model predicted a hit rate of 91.66%for the next hour’s comprehensive status score,and its high accur-acy was deemed satisfactory for the field.SHapley Additive exPlanations(SHAP)and regression fitting were applied to analyze the lin-ear quantitative relationship between the key variables and the comprehensive status score.When the furnace bottom center temperature was increased by 10℃,the comprehensive status score increased by 0.44.This method contributes to a more precise management and control of the comprehensive status of the blast furnace on-site. 展开更多
关键词 blast furnace comprehensive status machine learning cascade evaluation system combined prediction model
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Establishment and evaluation of a novel rat model of the fourth ventricle hemorrhage 被引量:1
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作者 Chuhua Fu Aoqi Liu +6 位作者 Yijia He Fei Li Zhouyang Jiang Peiwen Guo Zhi Chen Yujie Chen Hua Feng 《Animal Models and Experimental Medicine》 2025年第8期1480-1492,共13页
Background:Hemorrhagic expansion into the fourth ventricle is an independent risk factor for poor outcomes in intraventricular hemorrhage(IVH)patients.However,to date,available animal models of IVH are limited to mode... Background:Hemorrhagic expansion into the fourth ventricle is an independent risk factor for poor outcomes in intraventricular hemorrhage(IVH)patients.However,to date,available animal models of IVH are limited to models of supratentorial ventricular hemorrhage,and there are no specific models of fourth ventricle hemorrhage.This limitation hinders comprehensive basic research and the understanding of the pathophysiological changes that occur following fourth ventricle hemorrhage.Therefore,the development of an animal model of fourth ventricle hemorrhage is highly important.Methods:In this study,a novel rat model of fourth ventricle hemorrhage was established via autologous blood injection through the foramen of Magendie.Anesthetized rats were positioned in a stereotaxic apparatus with their heads tilted downward at an angle of approximately 20°relative to the vertical axis.A needle was inserted through the foramen,and autologous blood obtained from the rat's heart was injected into the fourth ventricle via a microinfusion pump.Systematic evaluations of the model were conducted using small-animal magnetic resonance imaging,histopathological analysis,and neurological function assessment.Results:The rats developed stable and reproducible fourth ventricle hematomas and ventricular dilation.They also exhibited acute-phase hydrocephalus and pathological features of perilesional brain tissue injury,with observed neurological deficits comparable to patients with fourth ventricle hemorrhage.Conclusion:This model successfully recapitulates the clinicopathological and pathophysiological characteristics of patients with fourth ventricle hemorrhage and can be utilized for further investigation into the pathophysiological mechanisms underlying posthemorrhagic hydrocephalus and perilesional brainstem tissue injury. 展开更多
关键词 animal model brainstem injury fourth ventricle hemorrhage HYDROCEPHALUS intraventricular hemorrhage
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Exploration on the Construction of an Intelligent Educational Evaluation System Integrating the CIPP Model and Artificial Intelligence Technology from the Perspective of New Engineering
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作者 Shun Yu Shasha Chen Yuxiu Li 《Journal of Contemporary Educational Research》 2025年第6期94-99,共6页
This study explores the feasibility of constructing an intelligent educational evaluation system based on the CIPP model and artificial intelligence technology in the context of new engineering disciplines.By integrat... This study explores the feasibility of constructing an intelligent educational evaluation system based on the CIPP model and artificial intelligence technology in the context of new engineering disciplines.By integrating the CIPP model with AI technology,a novel intelligent educational evaluation system was designed.Through experimental validation and case studies,the system demonstrated significant effectiveness in improving teaching quality,facilitating personalized student development,and optimizing educational resource allocation.Additionally,the study predicts potential changes this system could bring to the education industry and proposes relevant policy recommendations.Although the current research has limitations,with technological advancements in the future,this system is expected to provide stronger support for innovations in engineering education models. 展开更多
关键词 New engineering disciplines CIPP model Artificial intelligence Intelligent educational evaluation system Educational innovation
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