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Automatic Diagnosis of COVID-19 Patients from Unstructured Data Based on a Novel Weighting Scheme

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Computers, Materials & Continua 2023年第1期74卷 1375-1392页

作者： amir Yasseen mahdi Siti Sophiayati Yuhaniz Razak Faculty of Technology and Informatics Universiti Teknologi MalaysiaKuala Lumpur54100Malaysia Computer Sciences and Mathematics College University of Thi_QarThi_Qar64000Iraq

The extraction of features fromunstructured clinical data of Covid-19 patients is critical for guiding clinical decision-making and diagnosing this viral ***,an early and accurate diagnosis of COVID-19 can reduce the burden on healthcare *** this paper,an improved Term Weighting technique combined with Parts-Of-Speech(POS)Tagging is proposed to reduce dimensions for automatic and effective classification of clinical text related to Covid-19 *** Frequency-Inverse Document Frequency(TF-IDF)is the most often used term weighting scheme(TWS).However,TF-IDF has several developments to improve its drawbacks,in particular,it is not efficient enough to classify text by assigning effective weights to the terms in unstructured *** this research,we proposed a modification term weighting scheme:RTF-C-IEF and compare the proposed model with four extraction methods:TF,TF-IDF,TF-IHF,and *** experiment was conducted on two new datasets for COVID-19 *** first datasetwas collected from government hospitals in Iraq with 3053 clinical records,and the second dataset with 1446 clinical reports,was collected from several different *** on the experimental results using several popular classifiers applied to the datasets of Covid-19,we observe that the proposed scheme RTF-C-IEF achieves is a consistent performer with the best scores in most of the ***,the modifiedRTF-C-IEF proposed in the study outperformed the original scheme and other employed term weighting methods in most ***,the proper selection of term weighting scheme among the different methods improves the performance of the classifier and helps to find the informative term.

关键词： Covid-19 clinical text natural language processing TWS machine learning

基于多模型自适应方法的智能汽车路径跟踪控制

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重庆大学学报 2024年第3期47卷 1-15页

作者：梁艺潇李以农 amir Khajepour 郑玲余颖弘张紫微重庆大学机械与运载工程学院重庆400044 滑铁卢大学机械与机电工程学院加拿大安大略省滑铁卢市N2L3G1

路径跟踪控制是智能汽车的一项核心技术,跟踪效果的精确性和在各种路面附着条件下的鲁棒性是该技术的两大关键要素。但汽车动力学模型的不确定性,尤其是轮胎侧偏刚度的摄动使这两者难以同时得到满足。针对这一问题,将多模型自适应理论... 详细信息

路径跟踪控制是智能汽车的一项核心技术,跟踪效果的精确性和在各种路面附着条件下的鲁棒性是该技术的两大关键要素。但汽车动力学模型的不确定性,尤其是轮胎侧偏刚度的摄动使这两者难以同时得到满足。针对这一问题,将多模型自适应理论引入到智能汽车运动控制中处理不确定性系统的控制。首先,推导了多模型自适应控制律,提出了凸包构架下各个顶点的子模型对真实模型的自适应逼近律,并通过李雅普诺夫函数证明了所提出自适应律的收敛能力。在此基础上建立了汽车动力学模型和车辆-路径联合模型,并由多个顶点子模型构建可覆盖汽车轮胎侧偏刚度摄动范围的凸多面体,利用汽车动力学模型求解自适应率,通过车辆-路径联合模型,基于线性二次型方法(linear quadratic regulator,LQR)求解各个顶点的子模型处的反馈控制律,并通过所得出的自适应权重进行加权。基于Carsim/Simulink的联合仿真结果表明,所提出的多模型自适应路径跟踪控制器在保证鲁棒性的同时克服了传统鲁棒控制方法的保守性问题,与基于名义模型的LQR控制器和鲁棒保性能控制器相比,在高附着路面和低附着路面上都可以取得更好的控制效果,很好地解决了路径跟踪控制中精确性与鲁棒性之间的两难问题。最后,通过快速原型测试平台对算法进行了进一步的实验验证。结果表明,所提出的多模型自适应算法实时性良好,具有较好的工程应用潜力。

关键词：智能汽车车辆动力学路径跟踪控制模型不确定性多模型自适应控制

On the higher-order thermal vibrations of FG saturated porous cylindrical micro-shells integrated with nanocomposite skins in viscoelastic medium

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Defence Technology（防务技术） 2022年第8期18卷 1416-1434页

作者： Zeinab Soleimani-Javid Ehsan Arshid Saeed amir mahdi Bodaghi Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashanIran Department of Engineering School of Science and TechnologyNottingham Trent UniversityNottinghamNG118NSUK

Since the multi-layered structures are widely used nowadays, and due to interesting applications of cylindrical shells, this study is dedicated to analyzing free vibrational behaviors of functionally graded saturated porous micro cylindrical shells with two nanocomposite skins. Based on Biot's assumptions, constitutive relations for the core are presented and effective properties of the skins are determined via the rule of mixture. A sinusoidal theory is used to capture the shear deformation effects, and to account for the scale effects, the modified couple stress theory is employed which suggests a material length-scale parameter for predicting the results in small-dimension. With the aid of extended form of Hamilton's principle for dynamic systems, differential equations of motion are extracted. Fourier series functions are used to obtain natural frequencies and after validating them, a set of parametric studies are carried out. The results show the significant effects of porosity and Skempton coefficient, pores placement patterns, CNTs addition and distribution patterns, temperature variations, material length-scale parameter and viscoelastic medium on the natural frequencies of the microstructure. The outcomes of this work could be used to design and manufacture more reliable micro cylindrical structures in thermo-dynamical environments.

关键词： Vibration analysis Cylindrical shells Saturate porous materials Nanocomposite materials Carbon nanotubes Sinusoidal shear deformation theory Viscoelastic medium

Usage of Iranian scoria for copper and cadmium removal from aqueous solutions

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Journal of Central South University 2015年第10期22卷 3760-3769页

作者： Sara Seyfi amir Reza Azadmehr mahdi Gharabaghi Abbas Maghsoudi Department of Mining & Metallurgical Engineering Amirkabir University of Technology School of Mining Engineering College of Engineering University of Tehran

The competitive removal of copper and cadmium from aqueous solutions using scoria has been investigated. Scoria was characterized by various methods, such as XRD, XRF, FT-IR and SEM. The results show that scoria sample contained augite, enstatite, diopside, and olivine. These minerals were separated from each other and each mineral was then subjected to the adsorption experiments. It was found that the main absorbent constituent in scoria was augite. Finally, statistical experimental method was used to optimization of adsorption conditions（Initial concentration of copper and cadmium ions, the amount of scoria and temperature） for removal of Cu（II） and Cd（II） ions from solution in optimum conditions. The optimum conditions are obtained as follows： concentrations of Cu（II） and Cd（II） of 400×10-6 and 554×10-6, respectively; amount of scoria of 7 g; temperature of 38 ℃. Under these conditions Cu（II） and Cd（II） ions are absorbed onto the scoria more than 79% and 16%, respectively.

关键词： scoria adsorption removal factorial design

Identification of galectin-3 as a novel potential prognostic/predictive biomarker and therapeutic target for cerebral cavernous malformation disease

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Genes & Diseases 2024年第1期11卷 67-71页

作者： Souvik Kar Andrea Perrelli Kiran Kumar Bali Raffaella Mastrocola Arpita Kar Bushra Khan Luis Gand Arnab Nayak Christian Hartmann Wolfram SKunz amir Samii Helmut Bertalanffy Saverio Francesco Retta International Neuroscience Institute Rudolf-PichlmayrStrasse 4Hannover 30625Germany Department of Clinical and Biological Sciences University of TorinoOrbassano(TO)10043Italy CCM Italia Research Network National Coordination Center at the Department of Clinical and Biological SciencesUniversity of TorinoOrbassano(TO)10043Italy Department of Experimental Pain Research Mannheim Center for Translational Neuroscience(MCTN)Medical Faculty MannheimHeidelberg UniversityMannheim 68167Germany Department of Kidney Liver and Metabolic DiseasesChildren’s HospitalHannover Medical SchoolHannover 30625Germany Ricarda-Huch-Street-10B Hannover 30880Germany Institute of Molecular and Cell Physiology Hannover Medical SchoolHannover 30625Germany Department of Neuropathology Institute of PathologyHannover Medical SchoolHannover 30625Germany Institute of Experimental Epileptology and Cognition Research and Department of Epileptology University Hospital BonnVenusberg-Campus 1Bonn 53127Germany epartment of Pharmacology and Physiology University of Rochester Medical CenterRochesterNY 14642USA

cerebrovascular disease of genetic origin characterized by abnormally dilated capillaries and a wide spectrum of symptoms,including headaches,seizures,neurological deficits,and intracerebral *** unpredictable clinical course and the current lack of therapies make the identification of prognostic and predictive biomarkers an imperative research challenge.1 Herein,we provide evidence that galectin-3(Gal-3),a major tissue and circulating biomarker of oxidative stress and inflammation,is significantly up-regulated both in CCM patients and ***,wholetranscriptome sequencing,qRT-PCR,and Western blotting studies demonstrated a significant up-regulation of Gal-3 expression levels both in surgical CCM specimens and in blood samples of CCM patients.

关键词： inflammation cerebral dilated

Cardiac evaluation of renal transplant candidates with heart failure

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World Journal of Transplantation 2024年第4期14卷 44-49页

作者： Amer Ashaab Belal Alfonso Hernandez Santos Jr amir Kazory Department of Medicine Division of NephrologyUniversity of Florida College of MedicineGainesvilleFL 32610United States Division of Nephrology Hypertension and Renal TransplantationUniversity of FloridaGainesvilleFL 32608United States

Patients with advanced kidney disease are at elevated risk of developing heart failure and appropriate risk stratification is important to permit them to receive kidney *** American Heart Association and American College of Cardiology joint statement provides guidance on risk stratification for the major cause of heart failure for these patients in its recommendations for coronary heart *** we provide an overview of the available literature on risk strati-fication for nonischemic heart failure and functional heart disease states such as pulmonary *** of these options for optimizing these patients be-fore transplant include optimizing their volume status,often with more agg-ressive *** transplantation remains the treatment of choice for patients with advanced kidney disease and cardiac disease,the correction of the azotemic substances with kidney transplantation has been associated with imp-roved survival than remaining on dialysis *** findings in the studies reviewed here are expected to help clinicians refine current strategies for evalua-ting potential kidney transplant recipients.

关键词： Kidney transplantation Preoperative evaluation Clinical practice guidelines Heart failure Pulmonary hypertension

Neural network based approach for time to crash prediction to cope with software aging

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Journal of Systems Engineering and Electronics 2015年第2期26卷 407-414页

作者： Moona Yakhchi Javier Alonso mahdi Fazeli amir Akhavan Bitaraf Ahmad Patooghy School of Computer Science Institute for Research in Fundamental Sciences (IPM) Institute of Advanced Studies on Cybersecurity University of Leon Department of Computer Engineering Iran University of Technology

Recent studies have shown that software is one of the main reasons for computer systems unavailability. A growing ac- cumulation of software errors with time causes a phenomenon called software aging. This phenomenon can result in system per- formance degradation and eventually system hang/crash. To cope with software aging, software rejuvenation has been proposed. Software rejuvenation is a proactive technique which leads to re- moving the accumulated software errors by stopping the system, cleaning up its internal state, and resuming its normal operation. One of the main challenges of software rejuvenation is accurately predicting the time to crash due to aging factors such as me- mory leaks. In this paper, different machine learning techniques are compared to accurately predict the software time to crash un- der different aging scenarios. Finally, by comparing the accuracy of different techniques, it can be concluded that the multilayer per- ceptron neural network has the highest prediction accuracy among all techniques studied.

关键词： software reliability software rejuvenation machine learning

Stability Analysis and Performance Evaluation of Delayed Bilateral Telerobotic Systems over a Lossy Communication Channel

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Journal of Systems Science & Complexity 2021年第1期34卷 157-179页

作者： BAKHSHI Ali ALFI Alireza TALEBI Heidar Ali SOURATGAR amir Aboulfazl YOUSEFI mahdi Faculty of Electrical and Robotic Engineering Shahrood University of TechnologyShahrood 36199-95161Iran Power Plants Control Systems Technology Development Plan Department of monitoring and ControlNiroo Research InstituteTehran 14665-517Iran Real-Time and Robotics system Laboratory Faculty of Electrical EngineeringAmirkabir University of TechnologyHafez AvenueTehran 15914Iran Electrical and Computer Engineering Department The University of British Columbia2385East MallVan couverBC V6T 1Z4Canada

The focus of this paper is to address a novel control technique for stability and transparency analysis of bilateral telerobotic systems in the presence of data loss and time delay in the communication channel. Different control strategies have been reported to compensate the effects of time delay in the communication channel;however, most of them result in poor performance under data loss. First, a model for data loss is proposed using a finite series representation of a set of periodic continuous *** improve the performance and data reconstruction, a holder circuits is also introduced. The passivity of the overall system is provided via the wave variable technique based on the proposed model for the data loss. The stability analysis of the system is then derived using the Lyapunov theorem under the time delay and the data loss. Finally, experimental results are given to illustrate the capability of the proposed control technique.

关键词： Lossy channel passivity stability telerobotic transparency

Isoimperatorin alleviates acetic acid-induced colitis in rats

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Asian Pacific Journal of Tropical Biomedicine 2024年第4期14卷 147-153页

作者： Saied Goodarzi amir Hossein Abdolghaffari Behnaz Najafi Mostafa Pirali Hamedani Saeed Tavakoli Mahshad Marvi Maryam Baeeri Narguess Yassa Abbas Hadjiakhoondi Mohammad Abdollahi Zahra Tofighi Medicinal Plants Research Center Faculty of PharmacyTehran University of Medical SciencesTehranIran Department of Toxicology and Pharmacology Faculty of PharmacyTehran Medical SciencesIslamic Azad UniversityTehranIran Department of Pharmacognosy Faculty of PharmacyTehran University of Medical SciencesTehranIran Medicinal Plants Research Center Institute of Medicinal PlantsACECRKarajIran International Campus School of Pharmacy Tehran University of Medical SciencesTehranIran Toxicology and Diseases group The Pharmaceutical Sciences Research CenterTehran University of Medical SciencesTehranIran Department of Toxicology and Pharmacology Faculty of PharmacyTehran University of Medical SciencesTehranIran

Objective:To investigate the effect of isoimperatorin on histopathological and biochemical changes in acetic acid-induced colitis ***:Colitis was induced by intracolonic administration of acetic acid solution(4%v/v)in *** were divided into six groups including the sham group,the negative control group,the dexamethasone-treated group,and the groups treated with isoimperatorin(0.1,1,and 10 mg/kg/d by gavage).The treatments were administered for three days and then colonic status was assessed by macroscopic,histopathological,and biochemical ***:Isoimperatorin significantly alleviated colonic damage in a dose-dependent manner and improved histological changes in rats with acetic acid-induced *** also significantly reduced myeloperoxidase,TNF-α,IL-1β,and malodialdehyde ***:Isoimperatorin alleviates acetic acid-induced colitis in rats and may be a potential therapeutic agent for the treatment of colitis.

关键词： Isoimperatorin Inflammatory bowel disease Acetic acid Colitis TNF-α IL-1β