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Reinforcement Learning in process Industries:Review and perspective

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 283-300页

作者： Oguzhan Dogru Junyao Xie om prakash Ranjith Chiplunkar Jansen Soesanto Hongtian Chen Kirubakaran Velswamy Fadi Ibrahim Biao Huang Department of Chemical and Materials Engineering University of AlbertaEdmontonT6G 1H9Canada IEEE

This survey paper provides a review and perspective on intermediate and advanced reinforcement learning(RL)techniques in process industries. It offers a holistic approach by covering all levels of the process control hierarchy. The survey paper presents a comprehensive overview of RL algorithms,including fundamental concepts like Markov decision processes and different approaches to RL, such as value-based, policy-based, and actor-critic methods, while also discussing the relationship between classical control and RL. It further reviews the wide-ranging applications of RL in process industries, such as soft sensors, low-level control, high-level control, distributed process control, fault detection and fault tolerant control, optimization,planning, scheduling, and supply chain. The survey paper discusses the limitations and advantages, trends and new applications, and opportunities and future prospects for RL in process industries. Moreover, it highlights the need for a holistic approach in complex systems due to the growing importance of digitalization in the process industries.

关键词： process control process systems engineering reinforcement learning

Risk factors for long COVID in children and adolescents:a systematic review and meta-analysis

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World Journal of pediatrics 2024年第2期20卷 133-142页

作者： Daniel G.Rayner Elaine Wang Cloris Su om D.patel Stephanie Aleluya Alessandra Giglia Evelyn Zhu Maha Siddique Department of Health Research Methods Evidenceand ImpactFaculty of Health SciencesMcMaster University1280 Main St WHamiltonONL8S 4K1Canada Faculty of Health Sciences McMaster University1280 Main St WHamiltonON L8S 4K1Canada Faculty of Science McMaster University1280 Main St WHamiltonONL8S 4K1Canada

Background The long-term sequelae of COVID-19 in children and adolescents remain poorly understood and *** systematic review and meta-analysis sought to summarize the risk factors for long COVID in the pediatric *** We searched six databases from January 2020 to May 2023 for observational studies reporting on risk factors for long COVID or persistent symptoms those were present 12 or more weeks post-infection using multivariable regression *** registries,reference lists of included studies,and preprint servers were hand-searched for relevant ***-effects meta-analyses were conducted to pool odds ratios for each risk *** study risk of bias was rated using QUIpS,and the GRADE framework was used to assess the certainty of evidence for each unique *** Sixteen observational studies(N=46,262)were included,and 19 risk factors were amenable to *** moderate certainty in the evidence,age(per 2-year increase),allergic rhinitis,obesity,previous respiratory diseases,hospitalization,severe acute COVID-19,and symptomatic acute COVID-19 are probably associated with an increased risk of long *** sex,asthma,comorbidity,and heart diseases may be associated with an increased risk of long COVID,and Asian and Black races may be associated with a decreased risk of long *** did not observe any credible subgroup effects for any risk *** The current body of literature presents several compelling risk factors for the development of long COVID in the pediatric *** research is necessary to elucidate the pathophysiology of long COVID.

关键词： COVID-19 Long COVID post-acute COVID-19 syndrome pediatrics Risk factors

Recurrent acute pancreatitis as an initial presentation of primary hyperparathyroidism:A case report

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World Journal of Clinical Cases 2024年第29期12卷 6302-6306页

作者： Masood M Karim Hira Raza om parkash Department of Medicine The Aga Khan University HospitalKarachi 74800SindhPakistan Department of Surgery Aga Khan University HospitalKarachi 74800SindhPakistan

BACKGROUND With 4.9 to 35 instances per 100000 cases,hyperparathyroidism is one of the rarest causes of acute *** major cause of primary hyperparathyroidism is a parathyroid adenoma,which can manifest clinically in various *** SUMMARY We discuss the unusual case of a 13-year-old boy with recurrent pancreatitis as the initial presentation of primary *** cause of his recurrent pancreatitis remained unknown,and the patient had multiple admissions with acute pancreatitis over 3 *** diagnosis was delayed due to the initial normal levels of parathyroid hormone,which were later reported elevated in a subsequent episode where ultrasound neck and thyroid scintigraphy revealed a parathyroid adenoma as the underlying *** the diagnosis was made,he underwent surgical resection of the *** This case study stresses the importance of considering uncommon causes for recurrent pancreatitis.

关键词： Recurrent pancreatitis primary hyperparathyroidism Normal serum parathyroid hormone parathyroid adenoma Case report

Frequency regulation by fuzzy and binary control in a hybrid islanded microgrid

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Journal of Modern power Systems and Clean Energy 2015年第3期3卷 429-439页

作者： pamela MANJARRES om malik Department of Electrical and Computer Engineering University of CalgaryCalgaryABCanada

Islanded microgrids must be self-sufficient in terms of frequency and voltage control due to their islanded operation.A control strategy for frequency regulation by combining the operation of a wind generator,a diesel generator,a battery energy storage system and a dump load in a microgrid is proposed in this *** the proposed strategy,the control task is partitioned into two subtasks:1)choosing the appropriate element to be used for regulation,and 2)providing frequency regulation.A global controller chooses the element to ***,the frequency regulation is provided by separate individual *** proposed control strategy is tested on a microgrid with mixed types of generation and modeled on *** monitoring the power of individual elements and system frequency,it is shown that the proposed control strategy operates *** proposed strategy facilitates the integration of renewable energy sources and enhances frequency regulation.

关键词： Frequency regulation Fuzzy control Hybrid microgrid Automatic operation

A Study to Observe pulse pressure Variation after Induction with propofol for General Anesthesia

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World Journal of Cardiovascular Diseases 2024年第5期14卷 343-350页

作者： Kunal Tewari Vibhu Raghuvanshi Deepak Mishra Nitin pahuja Maj Jyotsna om Bahadur Thapa Department of Anaesthesiology and Critical Care Armed Forces Medical College Pune India Chauhan Medicity and Trauma Centre Pathankot India Department of Anaesthesiology and Critical Care Command Hospital (Southern Command) Pune India

Background and Aims: pulse pressure variation (ppV) is a reliable and predictive dynamic parameter presently being utilized for fluid responsiveness. In the operating room, fluid administration based on ppV monitoring helps the physician in deciding whether to volume resuscitate or use interventions in patients undergoing surgery. propofol is an intravenous induction agent which lowers blood pressure. There are multiple causes such as depression in cardiac output, and peripheral vasodilatation for hypotension. We undertook this study to observe the utility of ppV as a guide to fluid therapy after propofol induction. primary outcome of our study was to monitor ppV as a marker of fluid responsiveness for the hypotension caused by propofol induction. Secondary outcome included the correlation of ppV with other hemodynamic parameters like heart rate (HR), systolic blood pressure (SBp), and diastolic blood pressure (DBp);after induction with propofol at regular interval of time. Methods: A total number of 90 patients were recruited. Either of the radial artery was then cannulated under local anaesthesia with 20G VygonLeadercath arterial cannula and invasive monitoring transduced. A baseline recording of heart rate (HR), systolic blood pressure (SBp), diastolic blood pressure (DBp) and ppV was then recorded. patients were then induced with predetermined doses of propofol (2 mg/kg) and recordings of HR, SBp, DBp, and ppV were taken at 5, 10 and 15 minutes. Results: Intraoperatively, ppV was significantly higher at 5 minutes and significantly lower at 15 minutes after induction. It was observed that there were no statistically significant correlations between ppV and SBp or DBp. ppV was strongly and directly associated with HR. Conclusion: We were able to establish that ppV predicts fluid responsiveness in hypotension caused by propofol induction;and can be used to administer fluid therapy in managing such hypotension. However, ppV was not directly correlated with hypotensi

关键词： pulse pressure Variation (ppV) propofol Fluid Responsiveness

A Comparative Study between Landmark Based and Real Time Ultrasound Guided Sub Arachnoid Block

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Open Journal of Anesthesiology 2024年第4期14卷 118-125页

作者： Kunal Tewari om Bahadur Thapa Deepak Mishra Manjot Multani Jyotsna Sharma Akash Ray Mohapatra Sandhya Khwaunju Department of Anesthesiology and Critical Care Armed Forces Medical College Pune India Department of Anesthesiology and Critical Care AFMC Pune India

Background: Sub arachnoid block (SAB) performed by traditional landmark palpation technique can be inaccurate. This problem is exacerbated by altered patient anatomy due to obesity and age-related changes. A pre-procedural ultrasound scan of the lumbar spine has been shown to be of benefit in guiding lumbar epidural insertion in obstetric patients. Information on the use of real-time ultrasound (RUS) guided SAB, to date, been limited. This study compared RUS guided SAB to traditional landmark guided technique in patients undergoing spinal anesthesia for different surgical procedures. Methods: This was a prospective, single center, comparative observational study conducted in the department of anesthesiology at our center. 560 patients who underwent spinal anesthesia either by landmark based technique or real-time ultrasound-guided methods. The primary outcome was the first attempt success rate of dural puncture when employing the two methods. Results: Baseline characteristics were similar in the two study groups. The first attempt success rate of dural puncture in landmark guided group was 64.3% compared to 72.6% in the ultrasound guided group. This difference was not statistically significant. The procedure performance time was significantly shorter with landmark palpation compared to use of real-time ultrasound guided method. Conclusion: Use of RUS-guided technique does not significantly improve the first attempt success rate of SAB dural puncture during spinal anesthesia compared to the traditional landmark-guided technique.

关键词： Sub Arachnoid Block (SAB) Real Time Ultrasound (RUS)

Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study

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Open Journal of Anesthesiology 2024年第3期14卷 41-50页

作者： Kunal Tewari Sumanth pelluru Deepak Mishra Nitin pahuja Akash Ray Mohapatra Jyotsna Sharma om Bahadur Thapa Manjot Multani Department of Anesthesiology and Critical Care Armed Forces Medical College Pune India Department of Anesthesiology and Critical Care Military Hospital Bhopal India

Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases.

关键词： Chest X ray (CXR) Consolidation pulmonary edema pleural effusion Lung ultrasound (LUS) pneumothorax

Solitary kinetic Alfvén waves in a dense electron–positron–ion plasma with degenerate electrons and positrons

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plasma Science and Technology 2017年第12期19卷 42-49页

作者： Monzurul K AHMED om p SAH Depatment of physics Birjhora MahavidyalayaBongaigaon-783380AssamIndia

Through the use of a reductive perturbation technique, solitary kinetic Alfvén waves（KAWs） are investigated in a low but finite b（particle-to-magnetic pressure ratio） dense electron–positron–ion plasma where electrons and positrons are degenerate. The degenerate plasma model considered here permits the existence of sub-Alfvénic compressive solitary KAWs. The influence of r（equilibrium positron-to-ion density ratio）, sF（electron-to-positron Fermi temperature ratio）, b and obliqueness parameter lzon various characteristics of solitary KAWs are examined through numerical plots. We have shown that there exists a critical value of lzat which a soliton width attains its maximum value which decreases with an increase in r and *** is also found that solitons with a higher energy propagate more obliquely in the direction of an ambient magnetic field. The results of the present investigation may be useful for understanding low frequency nonlinear electromagnetic wave propagation in magnetized electron–positron–ion plasmas in dense stars. Specifically, the relevance of our investigation to a pulsar magnetosphere is emphasized.

关键词： kinetic Alfvén waves solitons electron–positron–ion plasma degenerate plasma Thomas–Fermi approximation

Solitary kinetic Alfven waves in dense plasmas with relativistic degenerate electrons and positrons

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plasma Science and Technology 2019年第4期21卷 85-93页

作者： Monzurul K AHMED om p SAH Department of physics Biijhora MahavidyalayaBongaigaon-783380AssamIndia

propagation of solitary kinetic Alfven waves(KAWs)is investigated in small but finite/3(particle-to-magnetic pressure ratio)collisionless dense plasma whose constituents are non degenerate wann ions,and relativistic degenerate electrons and *** the use of reductive perturbation technique,Kortweg-de Vries equation is derived to obtain small amplitude localized wave solution of *** effects of plasma 0,positron concentration,electron relativistic degeneracy parameter,ion thermal temperature and obliqueness parameter on solitary KAWs are *** results of this theoretical investigation are aimed at elucidating characteristics of kinetic Alfven solitary waves in relativistic degenerate e-p-i plasmas found in dense astrophysical objects specifically neutron stars and white dwarfs.

关键词： solitary kinetic Alfven waves dense plasmas electron-positron-ion plasma,relativistic degenerate plasma reductive perturbation technique