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A deep neural network based surrogate model for damage identification in full-scale structures with incomplete noisy measurements

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 393-410页

作者： tram BUI-ngOC Duy-Khuong Ly tam t tRUOng Chanachai tHOngCHOM t.ngUyEN-tHOI Laboratory for Computational Mechanics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Mechanical-Electrical and Computer Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Department of Computer Science Aarhus UniversityAarhus 8000Denmark thammasat University research unit in structural and foundation engineering Department of Civil EngineeringThammasat UniversityPathumthani 12120Thailand Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam thammasat School of Engineering Thammasat UniversityPathumthani 12120Thailand

the paper introduces a novel approach for detecting structural damage in full-scale structures using surrogate models generated from incomplete modal data and deep neural networks(DNNs).A significant challenge in this field is the limited availability of measurement data for full-scale structures,which is addressed in this paper by generating data sets using a reduced finite element(FE)model constructed by SAP2000 software and the MAtLAB programming *** surrogate models are trained using response data obtained from the monitored structure through a limited number of measurement *** proposed approach involves training a single surrogate model that can quickly predict the location and severity of damage for all potential *** achieve the most generalized surrogate model,the study explores different types of layers and hyperparameters of the training algorithm and employs state-of-the-art techniques to avoid overfitting and to accelerate the training *** approach’s effectiveness,efficiency,and applicability are demonstrated by two numerical *** study also verifies the robustness of the proposed approach on data sets with sparse and noisy measured ***,the proposed approach is a promising alternative to traditional approaches that rely on FE model updating and optimization algorithms,which can be computationally *** approach also shows potential for broader applications in structural damage detection.

关键词： vibration-based damage detection deep neural network full-scale structures finite element model updating noisy incomplete modal data

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Mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PtFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.MARKLUND M.BJORLIng y.SHI Division of Machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced polytetrafluoroethylene (CF/PtFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. Compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. Moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of CF/PtFE, the understanding of the underlying mechanisms are very limited. the objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/PtFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. the tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the CF/PtFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. Moreover, a loosely adhered tribofilm was observed on top of the CF/PtFE surface in presence of moisture. FtIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. the adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere

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Focal Nodular Hyperplasia: A Comprehensive Review with a Particular Focus on Pathogenesis and Complications

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Journal of Clinical and translational Hepatology 2024年第2期12卷 182-190页

作者： Jaimy Villavicencio Kim George y.Wu Division of Gastroenterology-Hepatology University of Connecticut Health CenterFarmingtonCTUSA

Focal nodular hyperplasia is a benign tumor of the liver that is often found incidentally with *** purpose of this review is to discuss the pathophysiology,rare complications that can occur due to these lesions,and management options.A literature review was performed on clinical trials and case reports involving focal nodular hyperplasia complications and management of these,as well as the proposed pathogenesis underlying these *** exposure to oral contraceptive pills and endogenous hormones have been thought to play a role in the development of these lesions,this has not been *** recently,they are thought to arise as a consequence of a vascular anomaly causing alterations in the expression of angiopoietin *** are rare,but previous cases have reported associated pain,rupture and compression of nearby structures(hepatic vein,stomach,biliary system).Resection of focal nodular hyperplasia is not usually ***,if there is associated pain with no other identifiable cause or presence of a large or growing lesion with risk of causing a complication,then surgical resection,radiofrequency ablation or arterial embolization should be considered.

关键词： Focal nodular hyperplasia Oral contraceptives Liver lesion

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Evaluation of Industrial Iot Service Providers with tOPSIS Based on Circular Intuitionistic Fuzzy Sets

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Computers, Materials & Continua 2024年第7期80卷 715-746页

作者： Elif Çalo˘glu Büyükselçuk Industrial Engineering Department Fenerbahçe University˙Istanbul34758Turkey

Industrial Internet of things(IIot)service providers have become increasingly important in the manufacturing industry due to their ability to gather and process vast amounts of data from connected devices,enabling manufacturers to improve operational efficiency,reduce costs,and enhance product *** platforms provide manufacturers with real-time visibility into their production processes and supply chains,allowing them to optimize operations and make informed *** addition,IIot service providers can help manufacturers create new revenue streams through the development of innovative products and services and enable them to leverage the benefits of emerging technologies such as Artificial Intelligence(AI)and machine ***,the implementation of IIot platforms in the manufacturing industry is crucial for companies seeking to remain competitive and meet the ever-increasing demands of customers in the digital *** this study,the evaluation criteria to be considered in the selection of IIot service provider in small andmedium-sized(SME)manufacturing enterprises will be determined and IIot service providers alternatives will be evaluated using the technique for order preference by similarity to an ideal solution(tOPSIS)method based on circular intuitionistic fuzzy *** on the assessments conducted in accordance with the literature review and expert consultations,a set of 8 selection criteria has been *** criteria encompass industry expertise,customer support,flexibility and scalability,security,cost-effectiveness,reliability,data analytics,as well as compatibility and *** evaluating these criteria,it was observed that the security criterion holds the highest significance,succeeded by cost-effectiveness,data analytics,flexibility and scalability,reliability,and customer support criteria,in descending order of *** the evaluation of seven distinct alternatives against these criteria,it was deduced tha

关键词： IIot manufacturing tOPSIS circular intuitionistic fuzzy sets

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Exponentially Convergent Multiscale Finite Element Method

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Communications on Applied Mathematics and Computation 2024年第2期6卷 862-878页

作者： yifan Chen thomas y.Hou yixuan Wang Applied and Computational Mathematics CaltechPasadena 91106USA

We provide a concise review of the exponentially convergent multiscale finite element method(ExpMsFEM)for efficient model reduction of PDEs in heterogeneous media without scale separation and in high-frequency wave *** ExpMsFEM is built on the non-overlapped domain decomposition in the classical MsFEM while enriching the approximation space systematically to achieve a nearly exponential convergence rate regarding the number of basis *** most generalizations of the MsFEM in the literature,the ExpMsFEM does not rely on any partition of unity *** general,it is necessary to use function representations dependent on the right-hand side to break the algebraic Kolmogorov n-width barrier to achieve exponential ***,there are online and offline parts in the function representation provided by the *** online part depends on the right-hand side locally and can be computed in parallel *** offline part contains basis functions that are used in the Galerkin method to assemble the stiffness matrix;they are all independent of the right-hand side,so the stiffness matrix can be used repeatedly in multi-query scenarios.

关键词： Multiscale method Exponential convergence Helmholtz's equation Domain decomposition Nonlinear model reduction

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CompactChain:an efficient stateless chain for UtXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： B Swaroopa REDDy t Uday Kiran REDDy Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UtXO(Unspent transaction Output)based blockchain systems into two RSA *** first accumulator is called transaction Output(tXO)commitment which represents the tXO *** second one is called Spent transaction Output(StXO)commitment which represents the StXO *** this work,we discuss three algorithms:(i)to update the tXO and StXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)to prove the transaction’s validity by providing a membership witness in tXO commitment and non-membership witness against StXO commitment for a coin being spent by a user;(iii)to update the witness for the coin that is not yet spent;the experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(transactions per second(tPS)).

关键词： stateless blockchain RSA Accumulator StXO commitment tXO commitment UtXO Non-interactive Proof of Exponentiation(NI-PoE) transactions per second(tPS)

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Prevalence and risk factors of depression among patients with perianal fistulizing Crohn’s disease

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World Journal of Psychiatry 2024年第5期14卷 715-725页

作者： Jing Li Wing-yi ng Li-Chao Qiao Fen yuan Xing Lan Li-Bei Zhu Bo-Lin yang Zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Acupuncture and Rehabilitation Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Psychological distress,especially depression,associated with perianal fistulizing Crohn’s disease(PFCD)is widespread and ***,there is a surprising paucity of studies to date that have sought to identify the prevalence and risk factors of depression associated with *** to estimate the prevalence of depressive symptoms and investigate the depression-related risk factors in patients with *** the study was conducted in the form of survey and clinical data collection via questionnaire and specialized medical *** symptoms,life quality,and fatigue severity of patients with PFCD were assessed by Patient Health Questionnaire-9,Inflammatory Bowel Disease Patient Quality of Life Questionnaire(IBDQ),and Inflammatory Bowel Disease(IBD)Fatigue Patient Self-assessment *** basic demographic information,overall disease features,perianal clinical information,and laboratory inflammation indicators were also *** regression analysis was ultimately used to ascertain the risk factors of depression associated with *** A total of 123 patients with PFCD were involved,and 56.91%were suffering from *** to multivariate logistic regression analysis,Perianal Disease Activity Index(PDAI)score[odds ratio(OR)=0.69,95%confidence interval(CI):0.50 to 0.95],IBDQ score(OR=0.93,95%CI:0.88 to 0.97),modified Van Assche index(OR=1.24,95%CI:1.01 to 1.53),and IBD Fatigue score(OR=1.72,95%CI:1.23 to 2.42)were independent risk factors of depression-related prevalence among patients with PFCD(Ptiple linear regression analysis revealed that the increasing perianal modified Van Assche index(βvalue=0.166,95%CI:0.02 to 0.31)and decreasing IBDQ score(βvalue=-0.116,95%CI:-0.14 to-0.09)were independently associated with the severity of depression(Pymptoms in PFCD patients have significantly high *** score,modified Van Assche index,quality of life,and fatigue severity

关键词： Crohn’s disease Fistula Depression Inflammatory bowel diseases Risk factors

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Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 89-103页

作者： Wenchen SHAN Jiepeng LIU yao DIng y.Frank CHEN Junwen ZHOU Institute of Smart City and Intelligent transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Civil Engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily generalized to the optimization problem of other structural systems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

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Subnormal Serum Liver Enzyme Levels:A Review of Pathophysiology and Clinical Significance

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Journal of Clinical and translational Hepatology 2024年第4期12卷 428-435页

作者： Elham M.youssef George y.Wu Biochemistry Department National Research CenterCairoEgypt Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Subnormal levels of liver enzymes,below the lower limit of normal on local laboratory reports,can be useful *** instance,subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney *** alkaline phosphatase levels may indicate the presence of hypophosphatasia,Wilson's disease,deficiencies of divalent ions,or *** levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis,the use of certain medications,and in bone ***,subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic *** aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

关键词： transaminases Vitamin B6 Celiac disease Renal insufficiency Hepatolenticular Degeneration Crohn disease Malnutrition Clofibrate Bone diseases Lead poisoning Anemia Hemolytic

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Etiologies of Splenic Venous Hypertension:A Review

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Journal of Clinical and translational Hepatology 2024年第6期12卷 594-606页

作者： Jasmine tidwell Bianca thakkar George y.Wu Department of Medicine University of Connecticut Health CenterFarmingtonCTUSA Division of Gastroenterology-Hepatology University of Connecticut Health CenterFarmingtonCTUSA

Splenic venous hypertension or left-sided portal hypertension is a rare condition caused by an obstruction of the splenic ***,it presents with upper gastrointestinal bleeding in the absence of liver *** can be classified based on the mechanism of development of splenic vein hypertension:compression,stenosis,inflammation,thrombosis,and surgically decreased splenic venous *** is established by various imaging modalities and should be suspected in patients with gastric varices in the absence of esophageal varices,splenomegaly,or *** management and prognosis vary depending on the underlying etiology but generally involve reducing splenic venous *** aim of this review was to summarize the etiologies of splenic venous hypertension according to the mechanism of development.

关键词： Splenic venous hypertension Left-sided portal hypertension Sinistral portal hypertension Splenic vein thrombosis Gastric varices Hematemesis Upper gastrointestinal bleeding

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