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Enhancing Secure Development in Globally Distributed Software Product Lines: A Machine Learning-Powered Framework for Cyber-Resilient Ecosystems
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作者 Marya Iqbal Yaser Hafeez +5 位作者 Nabil Almashfi Amjad Alsirhani Faeiz Alserhani Sadia Ali Mamoona Humayun Muhammad Jamal 《Computers, Materials & Continua》 SCIE EI 2024年第6期5031-5049,共19页
Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software devel-opment.However,the flexibility and global distribution inherent in modern systems pose significant challenges to... Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software devel-opment.However,the flexibility and global distribution inherent in modern systems pose significant challenges to managing SPL variability,underscoring the critical importance of robust cybersecurity measures.This paper advocates for leveraging machine learning(ML)to address variability management issues and fortify the security of SPL.In the context of the broader special issue theme on innovative cybersecurity approaches,our proposed ML-based framework offers an interdisciplinary perspective,blending insights from computing,social sciences,and business.Specifically,it employs ML for demand analysis,dynamic feature extraction,and enhanced feature selection in distributed settings,contributing to cyber-resilient ecosystems.Our experiments demonstrate the framework’s superiority,emphasizing its potential to boost productivity and security in SPLs.As digital threats evolve,this research catalyzes interdisciplinary collaborations,aligning with the special issue’s goal of breaking down academic barriers to strengthen digital ecosystems against sophisticated attacks while upholding ethics,privacy,and human values. 展开更多
关键词 machine Learning variability management CYBERSECURITY digital ecosystems cyber-resilience
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Development and validation of a machine learning-based early prediction model for massive intraoperative bleeding in patients with primary hepatic malignancies
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作者 Jin Li Yu-Ming Jia +4 位作者 Zhi-Lei Zhang Cheng-Yu Liu Zhan-Wu Jiang Zhi-Wei Hao Li Peng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期90-101,共12页
BACKGROUND Surgical resection remains the primary treatment for hepatic malignancies,and intraoperative bleeding is associated with a significantly increased risk of death.Therefore,accurate prediction of intraoperati... BACKGROUND Surgical resection remains the primary treatment for hepatic malignancies,and intraoperative bleeding is associated with a significantly increased risk of death.Therefore,accurate prediction of intraoperative bleeding risk in patients with hepatic malignancies is essential to preventing bleeding in advance and providing safer and more effective treatment.AIM To develop a predictive model for intraoperative bleeding in primary hepatic malignancy patients for improving surgical planning and outcomes.METHODS The retrospective analysis enrolled patients diagnosed with primary hepatic malignancies who underwent surgery at the Hepatobiliary Surgery Department of the Fourth Hospital of Hebei Medical University between 2010 and 2020.Logistic regression analysis was performed to identify potential risk factors for intraoperative bleeding.A prediction model was developed using Python programming language,and its accuracy was evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Among 406 primary liver cancer patients,16.0%(65/406)suffered massive intraoperative bleeding.Logistic regression analysis identified four variables as associated with intraoperative bleeding in these patients:ascites[odds ratio(OR):22.839;P<0.05],history of alcohol consumption(OR:2.950;P<0.015),TNM staging(OR:2.441;P<0.001),and albumin-bilirubin score(OR:2.361;P<0.001).These variables were used to construct the prediction model.The 406 patients were randomly assigned to a training set(70%)and a prediction set(30%).The area under the ROC curve values for the model’s ability to predict intraoperative bleeding were 0.844 in the training set and 0.80 in the prediction set.CONCLUSION The developed and validated model predicts significant intraoperative blood loss in primary hepatic malignancies using four preoperative clinical factors by considering four preoperative clinical factors:ascites,history of alcohol consumption,TNM staging,and albumin-bilirubin score.Consequently,this model holds promise for enhancing individualised surgical planning. 展开更多
关键词 Primary liver cancer Intraoperative bleeding machine learning Model
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Modeling urban redevelopment:A novel approach using time-series remote sensing data and machine learning
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作者 Li Lin Liping Di +6 位作者 Chen Zhang Liying Guo Haoteng Zhao Didarul Islam Hui Li Ziao Liu Gavin Middleton 《Geography and Sustainability》 CSCD 2024年第2期211-219,共9页
Accurate mapping and timely monitoring of urban redevelopment are pivotal for urban studies and decisionmakers to foster sustainable urban development.Traditional mapping methods heavily depend on field surveys and su... Accurate mapping and timely monitoring of urban redevelopment are pivotal for urban studies and decisionmakers to foster sustainable urban development.Traditional mapping methods heavily depend on field surveys and subjective questionnaires,yielding less objective,reliable,and timely data.Recent advancements in Geographic Information Systems(GIS)and remote-sensing technologies have improved the identification and mapping of urban redevelopment through quantitative analysis using satellite-based observations.Nonetheless,challenges persist,particularly concerning accuracy and significant temporal delays.This study introduces a novel approach to modeling urban redevelopment,leveraging machine learning algorithms and remote-sensing data.This methodology can facilitate the accurate and timely identification of urban redevelopment activities.The study’s machine learning model can analyze time-series remote-sensing data to identify spatio-temporal and spectral patterns related to urban redevelopment.The model is thoroughly evaluated,and the results indicate that it can accurately capture the time-series patterns of urban redevelopment.This research’s findings are useful for evaluating urban demographic and economic changes,informing policymaking and urban planning,and contributing to sustainable urban development.The model can also serve as a foundation for future research on early-stage urban redevelopment detection and evaluation of the causes and impacts of urban redevelopment. 展开更多
关键词 Urban redevelopment Urban sustainability Remote sensing Time-series analysis machine learning
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Machine Learning-Based Intelligent Auscultation Techniques in Congenital Heart Disease:Application and Development
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作者 Yang Wang Xun Yang +6 位作者 Mingtang Ye Yuhang Zhao Runsen Chen Min Da Zhiqi Wang Xuming Mo Jirong Qi 《Congenital Heart Disease》 SCIE 2024年第2期219-231,共13页
Congenital heart disease(CHD),the most prevalent congenital ailment,has seen advancements in the“dual indi-cator”screening program.This facilitates the early-stage diagnosis and treatment of children with CHD,subse-... Congenital heart disease(CHD),the most prevalent congenital ailment,has seen advancements in the“dual indi-cator”screening program.This facilitates the early-stage diagnosis and treatment of children with CHD,subse-quently enhancing their survival rates.While cardiac auscultation offers an objective reflection of cardiac abnormalities and function,its evaluation is significantly influenced by personal experience and external factors,rendering it susceptible to misdiagnosis and omission.In recent years,continuous progress in artificial intelli-gence(AI)has enabled the digital acquisition,storage,and analysis of heart sound signals,paving the way for intelligent CHD auscultation-assisted diagnostic technology.Although there has been a surge in studies based on machine learning(ML)within CHD auscultation and diagnostic technology,most remain in the algorithmic research phase,relying on the implementation of specific datasets that still await verification in the clinical envir-onment.This paper provides an overview of the current stage of AI-assisted cardiac sounds(CS)auscultation technology,outlining the applications and limitations of AI auscultation technology in the CHD domain.The aim is to foster further development and refinement of AI auscultation technology for enhanced applications in CHD. 展开更多
关键词 Congenital heart disease heart sound auscultation artificial intelligence machine learning
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Retrospective Analysis of Radiofrequency Ablation in Patients with Small Solitary Hepatocellular Carcinoma:Survival Outcomes and Development of a Machine Learning Prognostic Model
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作者 Qi-fan HE Yue XIONG +3 位作者 Yi-hui YU Xiang-chao MENG Tian-xu MA Zhong-hua CHEN 《Current Medical Science》 SCIE CAS 2024年第5期1006-1017,共12页
Background and Objective The effectiveness of radiofrequency ablation(RFA)in improving long-term survival outcomes for patients with a solitary hepatocellular carcinoma(HCC)measuring 5 cm or less remains uncertain.Thi... Background and Objective The effectiveness of radiofrequency ablation(RFA)in improving long-term survival outcomes for patients with a solitary hepatocellular carcinoma(HCC)measuring 5 cm or less remains uncertain.This study was designed to elucidate the impact of RFA therapy on the survival outcomes of these patients and to construct a prognostic model for patients following RFA.Methods This study was performed using the Surveillance,Epidemiology,and End Results(SEER)database from 2004 to 2017,focusing on patients diagnosed with a solitary HCC lesion≤5 cm in size.We compared the overall survival(OS)and cancer-specific survival(CSS)rates of these patients with those of patients who received hepatectomy,radiotherapy,or chemotherapy or who were part of a blank control group.To enhance the reliability of our findings,we employed stabilized inverse probability treatment weighting(sIPTW)and stratified analyses.Additionally,we conducted a Cox regression analysis to identify prognostic factors.XGBoost models were developed to predict 1-,3-,and 5-year CSS.The XGBoost models were evaluated via receiver operating characteristic(ROC)curves,calibration plots,decision curve analysis(DCA)curves and so on.Results Regardless of whether the data were unadjusted or adjusted for the use of sIPTWs,the 5-year OS(46.7%)and CSS(58.9%)rates were greater in the RFA group than in the radiotherapy(27.1%/35.8%),chemotherapy(32.9%/43.7%),and blank control(18.6%/30.7%)groups,but these rates were lower than those in the hepatectomy group(69.4%/78.9%).Stratified analysis based on age and cirrhosis status revealed that RFA and hepatectomy yielded similar OS and CSS outcomes for patients with cirrhosis aged over 65 years.Age,race,marital status,grade,cirrhosis status,tumor size,and AFP level were selected to construct the XGBoost models based on the training cohort.The areas under the curve(AUCs)for 1,3,and 5 years in the validation cohort were 0.88,0.81,and 0.79,respectively.Calibration plots further demonstrated the consistency between the predicted and actual values in both the training and validation cohorts.Conclusion RFA can improve the survival of patients diagnosed with a solitary HCC lesion≤5 cm.In certain clinical scenarios,RFA achieves survival outcomes comparable to those of hepatectomy.The XGBoost models developed in this study performed admirably in predicting the CSS of patients with solitary HCC tumors smaller than 5 cm following RFA. 展开更多
关键词 hepatocellular carcinoma radiofrequency ablation machine learning model overall survival cancer-specific survival
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Application of machine learning and deep learning in geothermal resource development: Trends and perspectives
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作者 Abdulrahman Al‐Fakih Abdulazeez Abdulraheem Sanlinn Kaka 《Deep Underground Science and Engineering》 2024年第3期286-301,共16页
This study delves into the latest advancements in machine learning and deep learning applications in geothermal resource development,extending the analysis up to 2024.It focuses on artificial intelligence's transf... This study delves into the latest advancements in machine learning and deep learning applications in geothermal resource development,extending the analysis up to 2024.It focuses on artificial intelligence's transformative role in the geothermal industry,analyzing recent literature from Scopus and Google Scholar to identify emerging trends,challenges,and future opportunities.The results reveal a marked increase in artificial intelligence(AI)applications,particularly in reservoir engineering,with significant advancements observed post‐2019.This study highlights AI's potential in enhancing drilling and exploration,emphasizing the integration of detailed case studies and practical applications.It also underscores the importance of ongoing research and tailored AI applications,in light of the rapid technological advancements and future trends in the field. 展开更多
关键词 artificial intelligence deep learning geothermal energy development machine learning
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Identifying influencing factors and characterizing key issues in urban sustainable development capacity through machine learning
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作者 Houbo Zhou Lijie Gao +1 位作者 Longyu Shi Qiuli Lv 《Chinese Journal of Population,Resources and Environment》 2024年第3期291-304,共14页
In response to the United Nations Sustainable Development Goals and China’s“Dual Carbon”Goals(DCGs means the goals of“Carbon Peak and carbon neutrality”),this paper from the perspective of the construction of Ch... In response to the United Nations Sustainable Development Goals and China’s“Dual Carbon”Goals(DCGs means the goals of“Carbon Peak and carbon neutrality”),this paper from the perspective of the construction of China’s Innovation Demonstration Zones for Sustainable Development Agenda(IDZSDAs),combines carbon emission-related metrics to construct a comprehensive assessment system for Urban Sustainable Development Capacity(USDC).After obtaining USDC assessment results through the assessment system,an approach combining Least Absolute Shrinkage and Selection Operator(LASSO)regression and Random Forest(RF)based on machine learning is proposed for identifying influencing factors and characterizing key issues.Combining Coupling Coordination Degree(CCD)analysis,the study further summarizes the systemic patterns and future directions of urban sustainable development.A case study on the IDZSDAs from 2015 to 2022 reveals that:(1)the combined identification method based on machine learning and CCD models effectively quantifies influencing factors and key issues in the urban sustainable development process;(2)the correspondence between influencing factors and key subsystems identified by the LASSO-RF combination model is generally consistent with the development situations in various cities;and(3)the machine learning-based combined recognition method is scalable and dynamic.It enables decision-makers to accurately identify influencing factors and characterize key issues based on actual urban development needs. 展开更多
关键词 Urban sustainable development capacity SDGs Dual Carbon Goals Factor identification Issue characterization machine learning
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Physics-embedded machine learning search for Sm-doped PMN-PT piezoelectric ceramics with high performance
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作者 辛睿 王亚祺 +6 位作者 房泽 郑凤基 高雯 付大石 史国庆 刘建一 张永成 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期81-88,共8页
Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different conce... Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of applications.Adjusting the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric coefficients.The combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical calculations.In this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different components.In contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric properties.Based on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are explored.We also find the components with the best piezoelectric property and comprehensive performance.Moreover,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs. 展开更多
关键词 Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(pmN-PT)ceramic physics-embedded machine learning piezoelectric coefficient Curie temperature
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自然光条件下光自芬顿/PMS协同体系处理新污染物的实验设计 被引量:1
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作者 刘芳 刘嘉梁 +3 位作者 安蓓雅 刘柃妤 李石 王永强 《实验技术与管理》 CAS 北大核心 2024年第1期26-36,共11页
为强化学生对新污染物处理理论和实验技能的掌握,设计了光自芬顿/过氧单硫酸盐(PMS)协同体系在自然光条件下对新污染物的强化降解实验。利用水热法和浸渍法制备改性氮化碳空心球MoS_(2)/TCN_(Cl-S)(P),以四环素(TC)作为新污染物代表,构... 为强化学生对新污染物处理理论和实验技能的掌握,设计了光自芬顿/过氧单硫酸盐(PMS)协同体系在自然光条件下对新污染物的强化降解实验。利用水热法和浸渍法制备改性氮化碳空心球MoS_(2)/TCN_(Cl-S)(P),以四环素(TC)作为新污染物代表,构建了光自芬顿/PMS协同体系,基于其耦合效应,提高在自然光条件下污染物的降解效率。结果表明,光自芬顿/PMS体系对TC在120min内的降解率可以达到80%,较不引入PMS的光自芬顿体系提高了30%。其原因在于光自芬顿反应中产生的H_(2)O_(2)与PMS发生协同作用,产生了更多的·O_(2)^(-)、SO_(4)^(-)·和^(1)O_(2)等活性自由基,从而提高了TC的降解效率。该实验设计体系有助于促进学生对高级氧化技术的掌握,为学生科研创新能力培养体系的构建提供参考。 展开更多
关键词 自然光 新污染物 改性氮化碳空心球 光自芬顿/pmS协同系统
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地区空气污染的“压力”与企业绿色转型的“动力”——基于城市PM2.5和公司并购的实证发现 被引量:2
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作者 蔡庆丰 舒少文 黄蕾 《厦门大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第1期50-63,共14页
地区空气污染会影响域内各类市场主体行为,包括微观企业决策。碳达峰、碳中和的提出要求各地加强空气污染治理,推动企业绿色转型,而绿色并购是企业绿色转型的重要方式。利用2013—2018年我国A股上市的污染企业发起的并购为样本,并手动... 地区空气污染会影响域内各类市场主体行为,包括微观企业决策。碳达峰、碳中和的提出要求各地加强空气污染治理,推动企业绿色转型,而绿色并购是企业绿色转型的重要方式。利用2013—2018年我国A股上市的污染企业发起的并购为样本,并手动搜集整理确定绿色并购样本,实证研究地区空气污染对域内企业绿色转型的影响。研究发现,地区空气污染加剧会提升域内污染企业绿色并购的意愿。在此基础上,通过并购前后企业信息披露质量和社会责任承担变化,研究发现地区空气污染加剧下的企业绿色转型并非源于自主绿色转型发展的内生“动力”,更多是外部“压力”下的“工具主义”行为。从影响路径来看,地区空气污染引致的压力会通过行业竞争和融资约束这两个途径影响污染企业绿色转型的“动力”。最后,异质性检验发现在市场化程度高和非国有企业样本,地区空气污染加剧对企业绿色并购的促进作用更为显著。 展开更多
关键词 地区空气污染 绿色转型 公司并购 pm2.5
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MLH1和PMS2在胃癌组织中的缺失水平及价值分析
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作者 陶飞 《中国现代医生》 2024年第15期24-28,共5页
目的探讨胃癌患者组织中错配修复(mismatch repair,MMR)蛋白MLH1、PMS2的缺失及表达水平,并分析高缺失者与患者临床特征的相关性。方法选取2014年5月至2022年3月青海省人民医院收治的275例胃癌患者为研究对象,回顾性收集患者MMR蛋白的... 目的探讨胃癌患者组织中错配修复(mismatch repair,MMR)蛋白MLH1、PMS2的缺失及表达水平,并分析高缺失者与患者临床特征的相关性。方法选取2014年5月至2022年3月青海省人民医院收治的275例胃癌患者为研究对象,回顾性收集患者MMR蛋白的表达资料,并结合临床特征进行统计学分析。结果在275例患者中,MLH1的缺失率为8.36%(23/275),PMS2的缺失率为18.18%(50/275),MLH1和PMS2的共同缺失率为7.27%(20/275)。MLH1的缺失率与PMS2的缺失率比较差异有统计学意义(P<0.05)。PMS2的缺失率与MLH1和PMS2的共同缺失率比较差异有统计学意义(P<0.05)。MLH1的缺失与胃癌患者的年龄、分化程度、Ki67指数、神经侵犯和Her-2状态有关(P<0.05);PMS2的缺失与胃癌患者的年龄、肿瘤部位和Ki67指数有关(P<0.05);MLH1和PMS2共同缺失与胃癌患者的年龄、肿瘤部位、肿瘤直径、分化程度、神经侵犯、Ki67指数和Her-2状态有关(P<0.05)。MLH1和PMS2在胃癌中表达呈正相关(r=0.539,P<0.001)。结论MLH1的缺失与胃癌患者较多的临床病理特征相关,MLH1、PMS2在胃癌中表达呈正相关。 展开更多
关键词 胃癌 错配修复蛋白 MLH1 pmS2 临床特征
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The development of machine learning-based remaining useful life prediction for lithium-ion batteries 被引量:10
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作者 Xingjun Li Dan Yu +1 位作者 Vilsen Søren Byg Store Daniel Ioan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期103-121,I0003,共20页
Lithium-ion batteries are the most widely used energy storage devices,for which the accurate prediction of the remaining useful life(RUL)is crucial to their reliable operation and accident prevention.This work thoroug... Lithium-ion batteries are the most widely used energy storage devices,for which the accurate prediction of the remaining useful life(RUL)is crucial to their reliable operation and accident prevention.This work thoroughly investigates the developmental trend of RUL prediction with machine learning(ML)algorithms based on the objective screening and statistics of related papers over the past decade to analyze the research core and find future improvement directions.The possibility of extending lithium-ion battery lifetime using RUL prediction results is also explored in this paper.The ten most used ML algorithms for RUL prediction are first identified in 380 relevant papers.Then the general flow of RUL prediction and an in-depth introduction to the four most used signal pre-processing techniques in RUL prediction are presented.The research core of common ML algorithms is given first time in a uniform format in chronological order.The algorithms are also compared from aspects of accuracy and characteristics comprehensively,and the novel and general improvement directions or opportunities including improvement in early prediction,local regeneration modeling,physical information fusion,generalized transfer learning,and hardware implementation are further outlooked.Finally,the methods of battery lifetime extension are summarized,and the feasibility of using RUL as an indicator for extending battery lifetime is outlooked.Battery lifetime can be extended by optimizing the charging profile serval times according to the accurate RUL prediction results online in the future.This paper aims to give inspiration to the future improvement of ML algorithms in battery RUL prediction and lifetime extension strategy. 展开更多
关键词 Lithium-ion batteries Remaining useful lifetime prediction machine learning Lifetime extension
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Development of a machine learning-based model for predicting risk of early postoperative recurrence of hepatocellular carcinoma 被引量:4
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作者 Yu-Bo Zhang Gang Yang +3 位作者 Yang Bu Peng Lei Wei Zhang Dan-Yang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第43期5804-5817,共14页
BACKGROUND Surgical resection is the primary treatment for hepatocellular carcinoma(HCC).However,studies indicate that nearly 70%of patients experience HCC recurrence within five years following hepatectomy.The earlie... BACKGROUND Surgical resection is the primary treatment for hepatocellular carcinoma(HCC).However,studies indicate that nearly 70%of patients experience HCC recurrence within five years following hepatectomy.The earlier the recurrence,the worse the prognosis.Current studies on postoperative recurrence primarily rely on postoperative pathology and patient clinical data,which are lagging.Hence,developing a new pre-operative prediction model for postoperative recurrence is crucial for guiding individualized treatment of HCC patients and enhancing their prognosis.AIM To identify key variables in pre-operative clinical and imaging data using machine learning algorithms to construct multiple risk prediction models for early postoperative recurrence of HCC.METHODS The demographic and clinical data of 371 HCC patients were collected for this retrospective study.These data were randomly divided into training and test sets at a ratio of 8:2.The training set was analyzed,and key feature variables with predictive value for early HCC recurrence were selected to construct six different machine learning prediction models.Each model was evaluated,and the bestperforming model was selected for interpreting the importance of each variable.Finally,an online calculator based on the model was generated for daily clinical practice.RESULTS Following machine learning analysis,eight key feature variables(age,intratumoral arteries,alpha-fetoprotein,preoperative blood glucose,number of tumors,glucose-to-lymphocyte ratio,liver cirrhosis,and pre-operative platelets)were selected to construct six different prediction models.The XGBoost model outperformed other models,with the area under the receiver operating characteristic curve in the training,validation,and test datasets being 0.993(95%confidence interval:0.982-1.000),0.734(0.601-0.867),and 0.706(0.585-0.827),respectively.Calibration curve and decision curve analysis indicated that the XGBoost model also had good predictive performance and clinical application value.CONCLUSION The XGBoost model exhibits superior performance and is a reliable tool for predicting early postoperative HCC recurrence.This model may guide surgical strategies and postoperative individualized medicine. 展开更多
关键词 machine learning Hepatocellular carcinoma Early recurrence Risk prediction models Imaging features Clinical features
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实现纹波电流还原的PMSM端口模拟算法
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作者 李易庭 高泽鹏 +1 位作者 李梦梦 王普毅 《汽车工程》 EI CSCD 北大核心 2024年第8期1469-1478,共10页
电机模拟器作为一种模拟电机端口特性的三相电力电子装置,为电驱动系统的测试提供了高效的测试手段。电机模拟器还原目标电机端口特性的标志是精确还原目标电机的工作电流,现有研究实现了基波电流及较低阶次谐波电流的还原,但针对电机... 电机模拟器作为一种模拟电机端口特性的三相电力电子装置,为电驱动系统的测试提供了高效的测试手段。电机模拟器还原目标电机端口特性的标志是精确还原目标电机的工作电流,现有研究实现了基波电流及较低阶次谐波电流的还原,但针对电机在电机控制器驱动下的高频纹波电流的还原仍严重依赖滤波电感与目标电机电感的匹配,降低了电机模拟器的通用性。为此,本文基于电路等效虚拟法将永磁同步电机等效电路拆分为两部分,一部分由电机模拟器实际电路代替,另一部分由控制算法模拟,并结合无差拍电流预测控制对控制差拍进行了补偿,提出了前馈解耦无差拍电流跟随策略。实验结果表明,基于新提出的永磁同步电机端口模拟算法,电机模拟器可以在不更换电感的情况下模拟不同参数的永磁同步电机,高频纹波电流的频域跟踪误差从传统策略的160%降低至20%,显著提高了电机模拟器对永磁同步电机端口特性的模拟精度。 展开更多
关键词 电动汽车 电机模拟器 前馈解耦控制 电机控制
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Interpretable machine learning optimization(InterOpt)for operational parameters:A case study of highly-efficient shale gas development 被引量:2
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作者 Yun-Tian Chen Dong-Xiao Zhang +1 位作者 Qun Zhao De-Xun Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1788-1805,共18页
An algorithm named InterOpt for optimizing operational parameters is proposed based on interpretable machine learning,and is demonstrated via optimization of shale gas development.InterOpt consists of three parts:a ne... An algorithm named InterOpt for optimizing operational parameters is proposed based on interpretable machine learning,and is demonstrated via optimization of shale gas development.InterOpt consists of three parts:a neural network is used to construct an emulator of the actual drilling and hydraulic fracturing process in the vector space(i.e.,virtual environment);:the Sharpley value method in inter-pretable machine learning is applied to analyzing the impact of geological and operational parameters in each well(i.e.,single well feature impact analysis):and ensemble randomized maximum likelihood(EnRML)is conducted to optimize the operational parameters to comprehensively improve the efficiency of shale gas development and reduce the average cost.In the experiment,InterOpt provides different drilling and fracturing plans for each well according to its specific geological conditions,and finally achieves an average cost reduction of 9.7%for a case study with 104 wells. 展开更多
关键词 Interpretable machine learning Operational parameters optimization Shapley value Shale gas development Neural network
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Comparison and development of machine learning for thalidomideinduced peripheral neuropathy prediction of refractory Crohn’s disease in Chinese population 被引量:1
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作者 Jing Mao Kang Chao +9 位作者 Fu-Lin Jiang Xiao-Ping Ye Ting Yang Pan Li Xia Zhu Pin-Jin Hu Bai-Jun Zhou Min Huang Xiang Gao Xue-Ding Wang 《World Journal of Gastroenterology》 SCIE CAS 2023年第24期3855-3870,共16页
BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure... BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure.TiPN is rarely predictable and recognized,especially in CD.It is necessary to develop a risk model to predict TiPN occurrence.AIM To develop and compare a predictive model of TiPN using machine learning based on comprehensive clinical and genetic variables.METHODS A retrospective cohort of 164 CD patients from January 2016 to June 2022 was used to establish the model.The National Cancer Institute Common Toxicity Criteria Sensory Scale(version 4.0)was used to assess TiPN.With 18 clinical features and 150 genetic variables,five predictive models were established and evaluated by the confusion matrix receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),specificity,sensitivity(recall rate),precision,accuracy,and F1 score.RESULTS The top-ranking five risk variables associated with TiPN were interleukin-12 rs1353248[P=0.0004,odds ratio(OR):8.983,95%confidence interval(CI):2.497-30.90],dose(mg/d,P=0.002),brainderived neurotrophic factor(BDNF)rs2030324(P=0.001,OR:3.164,95%CI:1.561-6.434),BDNF rs6265(P=0.001,OR:3.150,95%CI:1.546-6.073)and BDNF rs11030104(P=0.001,OR:3.091,95%CI:1.525-5.960).In the training set,gradient boosting decision tree(GBDT),extremely random trees(ET),random forest,logistic regression and extreme gradient boosting(XGBoost)obtained AUROC values>0.90 and AUPRC>0.87.Among these models,XGBoost and GBDT obtained the first two highest AUROC(0.90 and 1),AUPRC(0.98 and 1),accuracy(0.96 and 0.98),precision(0.90 and 0.95),F1 score(0.95 and 0.98),specificity(0.94 and 0.97),and sensitivity(1).In the validation set,XGBoost algorithm exhibited the best predictive performance with the highest specificity(0.857),accuracy(0.818),AUPRC(0.86)and AUROC(0.89).ET and GBDT obtained the highest sensitivity(1)and F1 score(0.8).Overall,compared with other state-of-the-art classifiers such as ET,GBDT and RF,XGBoost algorithm not only showed a more stable performance,but also yielded higher ROC-AUC and PRC-AUC scores,demonstrating its high accuracy in prediction of TiPN occurrence.CONCLUSION The powerful XGBoost algorithm accurately predicts TiPN using 18 clinical features and 14 genetic variables.With the ability to identify high-risk patients using single nucleotide polymorphisms,it offers a feasible option for improving thalidomide efficacy in CD patients. 展开更多
关键词 Thalidomide-induced peripheral neuropathy Refractory Crohn’s disease Neurotoxicity prediction models machine learning Gene polymorphisms
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PMS协同Ce改性BiOBr材料光催化降解四环素 被引量:1
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作者 李文涛 黄雪咪 +5 位作者 钟文祥 黄芳 杨惠彬 郭建宁 肖峰 钟润生 《环境保护科学》 CAS 2024年第1期155-162,共8页
采用溶剂热合成法制备Ce(Ⅲ)改性BiOBr催化剂(Ce/Bi摩尔比0.1%~2%),通过XRD、SEM-mapping、XPS、UV-Vis等手段对其结构进行表征分析;以四环素为目标污染物,首次提出构建PMS/Ce(Ⅲ)改性BiOBr光催化体系降解四环素,考察催化剂种类、催化... 采用溶剂热合成法制备Ce(Ⅲ)改性BiOBr催化剂(Ce/Bi摩尔比0.1%~2%),通过XRD、SEM-mapping、XPS、UV-Vis等手段对其结构进行表征分析;以四环素为目标污染物,首次提出构建PMS/Ce(Ⅲ)改性BiOBr光催化体系降解四环素,考察催化剂种类、催化剂投加量、PMS摩尔浓度和p H等因素对反应体系降解四环素效果的影响。结果表明:Ce(Ⅲ)和Bi(Ⅲ)发生同晶置换,使得Ce(Ⅲ)改性BiOBr的最大吸收波长出现蓝移,提高光生电子和空穴的分离效率;PMS协同Ce(Ⅲ)改性BiOBr光催化降解四环素最佳条件:Ce与Bi的摩尔比为1%,投加量为1.0 g/L,PMS浓度为0.3 mmol/L,pH=9;四环素降解过程中,反应体系内主要活性物种为空穴,其贡献远高于硫酸根自由基和单线态氧。经重复利用实验证实,Ce改性BiOBr材料结构具有良好的稳定性。 展开更多
关键词 Ce改性BiOBr 过一硫酸盐 光催化降解 四环素 活性物种
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Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning 被引量:9
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作者 Ling Wang Deng-Yan Long 《World Journal of Clinical Cases》 SCIE 2024年第7期1235-1242,共8页
BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective pr... BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration. 展开更多
关键词 Intensive care unit-acquired weakness Risk factors machine learning PREVENTION Strategies
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基于改进PM扩散方程的NSST域声呐图像融合
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作者 冯时宇 张钟铮 +1 位作者 赵振贺 周凯 《火力与指挥控制》 CSCD 北大核心 2024年第6期200-207,共8页
针对声呐图像边缘特征信息模糊丢失等问题,为使图像尽可能包含更多边缘和纹理特征等信息,提出一种基于改进PM扩散方程非下采样剪切波变换声呐图像融合改进算法。采用非线性扩散滤波对NSST多尺度分解进行改进,将多幅源图像分解为高频系... 针对声呐图像边缘特征信息模糊丢失等问题,为使图像尽可能包含更多边缘和纹理特征等信息,提出一种基于改进PM扩散方程非下采样剪切波变换声呐图像融合改进算法。采用非线性扩散滤波对NSST多尺度分解进行改进,将多幅源图像分解为高频系数和低频系数,并且结合局部能量及PCNN方法对高低频系数进行融合,经过逆变换重构为融合图像。经过实验验证与其他算法相比,所提方法能够较好地保留源图像中的边缘特征信息,在含噪声声呐图像上表现较为明显。 展开更多
关键词 非下采样剪切波变换 声呐图像 图像融合 pm扩散方程 边缘提取
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非金属原子掺杂碳基材料活化PMS降解污染物及其催化机制
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作者 诸英杰 唐志红 《有色金属材料与工程》 CAS 2024年第5期52-62,共11页
碳基材料具有较大的比表面积、良好的耐酸碱性、结构易于改性以及环境友好等特性,在催化活化过氧单硫酸盐(peroxymonosulfate,PMS)方面发挥了重要作用。理解碳基材料的结构和PMS活化机制对进一步设计高性能催化剂有着十分重要的指导意... 碳基材料具有较大的比表面积、良好的耐酸碱性、结构易于改性以及环境友好等特性,在催化活化过氧单硫酸盐(peroxymonosulfate,PMS)方面发挥了重要作用。理解碳基材料的结构和PMS活化机制对进一步设计高性能催化剂有着十分重要的指导意义。主要综述了N、B、P原子的单掺杂碳基催化剂及其研究现状,分析了不同杂原子掺杂碳基催化剂活化PMS的反应原理,详细阐释了杂原子掺杂改善反应活性的作用机制。此外,总结了不同类型杂原子掺杂CNT用于苯酚降解,并着重阐述了杂原子掺杂CNT活性改善的主要因素。最后,提出了当前杂原子掺杂碳基材料面临的一些挑战,给出了相关的解决建议并对该领域的发展进行了展望。 展开更多
关键词 活化pmS 杂原子掺杂 碳基催化剂 催化机制
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