检索结果-南通市图书馆

Reinforcement Learning in Process Industries:Review and Perspective

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

A Study to Observe Pulse Pressure Variation after Induction with Propofol for General Anesthesia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Fault Detection for Microgrid Feeders Using Features Based on Superimposed Positive-sequence Power

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1948-1958页

作者： Salauddin Ansari om Hari Gupta om P.Malik Department of Electrical Engineering National Institute of TechnologyJamshedpur 831014India IEEE Department of Electrical and Software Engineering University of Calgary2500 University Drive NWCalgary Alberta T2N 1N4Canada

With the integration of distributed generation(DG) into a microgrid, fault detection has become a major task to accomplish. A scheme for microgrid feeder protection based on a newly proposed feature, ΔRP, defined as the ratio of the sum of positive-sequence real power(PSRP) at the two ends of the feeder to the larger of the PSRPs among the two ends, is proposed. If ΔRP is larger than a threshold, an internal fault is detected;otherwise, the fault is external or there is no fault. The proposed scheme is tested in various scenarios, including fault type, fault resistance, fault location, fault inception angle, varying DG penetration levels, and simultaneous, evolving, and composite faults. In addition to this, the proposed scheme offers a robust performance when subjected to noise, synchronization error, changes in sampling frequency, and changes in the topology of a microgrid. The dominancy of the proposed scheme is proven by a comprehensive comparative study with various available recent schemes. Test results on the IEEE 13-bus network indicate the viability of the proposed protection scheme for a microgrid. Finally, the proposed scheme has been validated on a real-time simulator.

关键词： Fault detection distributed generation microgrid protection superimposed power

Power Quality Improvement and Signal Conditioning of PV Array and Grid Interfaced Off-board Charger for Electric Vehicles with V2G and G2V Capabilities

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electrical Engineering 2023年第4期9卷 132-143页

作者： Shailendra Kumar Tapesh Upadhyay om Hari Gupta Department of Electrical Engineering Indian Institute of TechnologyBhilai 492015India Department of Electrical Engineering Maulana Azad National Institute of Technology(MANIT)Bhopal 462003India Department of Electrical Engineering National Institute of TechnologyJamshedpur 831014India

In this work,we present a photovoltaic(PV)-based off-board charging system integrated with the grid using a voltage source converter(VSC).The control of the grid-tied off-board charger is derived from the joint logarithmic hyperbolic cosine robust sparse adaptive filter(JLHCAF)*** algorithm effectively tracks the fundamental component of the load current in a short duration,providing a good dynamic *** to its robustness against impulsive interference,the JLHCAF outperforms other sparsity-aware robust algorithms The cascaded proportional-integral(PI)controller is used to control the bidirectional buck-boost converter for electric vehicle(EV)charging/discharging,which acts in buck operation if the EV is being charged and in boost operation if it is *** reference DC link voltage for the controller is derived by using adaptive MPPT *** bidirectional properties of the system enable various functions,including grid-to-vehicle(G2V),vehicle-to-grid(V2G),PV source-to-grid(PV2G),vehicle-to-home(V2H),and PV source-to-vehicle(PV2V)***,the system can supply power to critical nonlinear *** control strategy ensures compliance with the power quality requirements set by the IEEE standard,as demonstrated in the *** validate the effectiveness of the proposed system,we conducted tests under dynamic conditions by disconnecting and reconnecting household ***,the off-board charging system was subjected to actual conditions,such as variations in solar PV insolation,and its steady-state performance was evaluated through simulation and laboratory experimental *** results,including total harmonic distortion(THD),support the validation of the developed charging system.

关键词： Grid to vehicle(G2V) vehicle to grid(V2G) off-board charger(OBC) power quality total harmonic distortion(THD) electrical vehicles(EVs)

The influence of AAR coupler features on estimation of in-train forces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Railway Engineering Science 2023年第3期31卷 233-251页

作者： om Prakash Yadav Nalinaksh S.Vyas Department of Mechanical Engineering Indian Institute of Technology KanpurKanpurUttar Pradesh 208016India

Inadequate management of large in-train forces transferred through coupler systems of a railway train leads to running and structural failures of *** these phenomena and their mitigation requires accurate estimation of relative motions and in-train forces between vehicle *** numerical studies have ignored inertia of coupling elements and the impacts between ***,existing models underestimate the additional dynamic variations in in-train *** multi-body dynamic models of two AAR(Association of American Railroads)coupler systems used in passenger and freight trains are developed,incorporating coupler inertia and various *** to the modeling and simulation com-plexities involved in a full train model,with such details of coupler system,actual longitudinal train dynamics is not studied.A system comprising only two coupling units,inter-connecting two consecutive vehicles,is *** system has been fixed at one end and an excitation force is applied at the other end,to mimic a relative force transmission through combined coupler *** results obtained from this representative system show that,noticeable influence in in-train forces are expected due to the combined effect of inertia of couplers and intermittent impacts between couplers in the slack *** amplitude of longitudinal reaction force,transferred from draft gear housing to vehicle body,is expected to be significantly higher than that predicted using existing models of coupler *** is also observed that the couplers and knuckles are subjected to significant longitudinal and lateral contact forces,due to the intermittent impacts between ***,accurate estimation of draft gear reaction force and impact forces between couplers are essential to design vehicle and coupler components,respectively.

关键词： Automatic railway coupler Draft gear Longitudinal train dynamics In-train forces Coupler slack Intermittent impacts

Global geoepidemiology of gastrointestinal surgery rates in Crohn’s disease

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2024年第6期16卷 1835-1844页

作者： Simcha Weissman Muhammad Aziz Ayrton Bangolo Vignesh K Nagesh Htat Aung Midhun Mathew Lino Garcia Shiva A Chandar Praveena Karamthoti Harinder Bawa Aseel Alshimari Yabets Kejela Nazish Mehdi Chrishanti A Joseph Athri Kodali Rohan Kumar Priya Goyal Sanya Satheesha Fnu Nivedita Nicole Tesoro Tanni Sethi Gurpreet Singh Areej Belal Alina Intisar Hirra Khalid Samuel Cornwell Suchith B Suresh Kareem Ahmed Karabo K Marole om P Anand Rahat B Reshi Tej I Mehta Sameh Elias Joseph D Feuerstein Department of Medicine Hackensack Meridian Health Palisades Medical CenterNorth BergenNJ 07047United States Division of Gastroenterology and Hepatology University of Toledo Medical CenterToledoOH 43614United States Department of Medicine University of WashingtonSeattleWA 98195United States Department of Radiology Johns Hopkins University HospitalBaltimoreMD 21218United States Division of Gastroenterology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215United States

BACKGROUND Data regarding the worldwide gastrointestinal surgery rates in patients with Crohn’s disease(CD)remains *** To systematically review the global variation in the rates of surgery in *** A comprehensive search analysis was performed using multiple electronic databases from inception through July 1,2020,to identify all full text,randomized controlled trials and cohort studies pertaining to gastrointestinal surgery rates in adult patients with *** included continent based demographic data,CD surgery rates over time,as well as the geoepidemiologic variation in CD surgery *** analyses were conducted using *** Twenty-three studies spanning four continents were *** median proportion of persons with CD who underwent gastrointestinal surgery in studies from North America,Europe,Asia,and Oceania were 30%(range:1.7%-62.0%),40%(range:0.6%-74.0%),17%(range:16.0%-43.0%),and 38%*** clear association was found regarding the proportion of patients undergoing gastrointestinal surgery over time in North America(R^(2)=0.035)and Europe(R^(2)=0.100).A moderate,negative association was seen regarding the proportion of patients undergoing gastrointestinal surgery over time(R^(2)=0.520)in *** There appears to be significant inter-continental variation regarding surgery rates in *** evidencebased guidelines accounting for the geographic differences in managing patients with CD is ***,as a paucity of data on surgery rates in CD exists outside the North American and European continents,future studies,particularly in less studied locales,are warranted.

关键词： Gastrointestinal surgery Crohn’s disease Geoepidemiology Inflammatory bowel disease Prevalence