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Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： ali A.Abdel-Aziz Mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

Enhancing Renewable Energy Integration:A Gaussian-Bare-Bones Levy Cheetah Optimization Approach to Optimal Power Flow in Electrical Networks

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1339-1370页

作者： ali S.Alghamdi Mohamed A.Zohdy Saad Aldoihi Department of Electrical Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia Electrical and Computer Engineering Department Oakland UniversityRochesterMI48309USA Institute of Earth and Space Science King Abdulaziz City for Science and Technology(KACST)Riyadh11442Saudi Arabia Computer Science and Systems Engineering Institute Polytechnique de ParisPalaiseau CedexFrance

In the contemporary era,the global expansion of electrical grids is propelled by various renewable energy sources(RESs).Efficient integration of stochastic RESs and optimal power flow(OPF)management are critical for network *** study introduces an innovative solution,the Gaussian Bare-Bones Levy Cheetah Optimizer(GBBLCO),addressing OPF challenges in power generation systems with stochastic *** primary objective is to minimize the total operating costs of RESs,considering four functions:overall operating costs,voltage deviation management,emissions reduction,voltage stability index(VSI)and power loss ***,a carbon tax is included in the objective function to reduce carbon *** scrutiny,using modified IEEE 30-bus and IEEE 118-bus systems,validates GBBLCO’s superior performance in achieving optimal *** results demonstrate GBBLCO’s efficacy in six optimization scenarios:total cost with valve point effects,total cost with emission and carbon tax,total cost with prohibited operating zones,active power loss optimization,voltage deviation optimization and enhancing voltage stability index(VSI).GBBLCO outperforms conventional techniques in each scenario,showcasing rapid convergence and superior solution ***,GBBLCO navigates complexities introduced by valve point effects,adapts to environmental constraints,optimizes costs while considering prohibited operating zones,minimizes active power losses,and optimizes voltage deviation by enhancing the voltage stability index(VSI)*** research significantly contributes to advancing OPF,emphasizing GBBLCO’s improved global search capabilities and ability to address challenges related to local *** emerges as a versatile and robust optimization tool for diverse challenges in power systems,offering a promising solution for the evolving needs of renewable energy-integrated power grids.

关键词： Renewable energy integration optimal power flow stochastic renewable energy sources gaussian-bare-bones levy cheetah optimizer electrical network optimization carbon tax optimization

Earliest megafossils of scandent calamoid palms from the Deccan Intertrappean Beds of Central India and their paleobiogeographic implications

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Journal of Palaeogeography 2024年第3期13卷 509-527页

作者： Sanchita Kumar Kaustav Roy Robert A.Spicer Mahasin ali Khan Palaeobotany and Palynology Laboratory Department of BotanySidho-Kanho-Birsha UniversityRanchi RoadPurulia-723104India CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton KeynesMK76AAUK State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Two well-preserved petrified palm stems from the latest Maastrichtian(Late Cretaceous) to earliest Danian(Early Paleocene) sediments of the Deccan Intertrappean Beds of Madhya Pradesh, Central India are described. Their significant anatomical characteristics include a Calamus-type general stem pattern,the presence of well-preserved fibrovascular bundles(fvbs) with two wide metaxylem vessel elements(230 μm-250 μm) and one phloem strand, uniform density of fvbs, lack of continuity between protoxylem and metaxylem vessel elements, and an absence of centrifugal differentiation of sclerenchymatous fibrous *** features reveal a close resemblance to those of extant genera of scandent Calamoideae. The permineralized stems are described as a new species namely, Palmoxylon calamoides Kumar, Roy et Khan sp. *** fossils represent the oldest reliable fossil records of this family, supporting their Gondwanan origin, their importance in tracing their migration pathways from India to Europe and other continents after the docking of the Indian subcontinent with Eurasia during the Paleocene, and an “Out-of-India” dispersal hypothesis. Today the subfamily Calamoideae is disjunctly occurred in Africa, Asia, Australia, Europe, and South America, but the poor deep-time fossil record of this subfamily with a small number of Cenozoic fossils makes hypotheses concerning its origin and dispersal difficult to evaluate. The present study has significant implications for the origin and migration of this subfamily and the paleoclimate.

关键词： Scandent Calamoideae Stem anatomy K-Pg Paleobiogeography Paleoclimate Central India

Stratigraphy of the Alveolina elliptica group from the Middle Eocene of Iran:Calibration with calcareous nannofossils biozones and description of Alveolina ozcani n. sp.

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Journal of Palaeogeography 2024年第1期13卷 54-79页

作者： Mehdi Hadi Lorenzo Consorti ali Bahrami Mohammad Parandavar Saeed Khorramdel Department of Geology Faculty of SciencesUniversity of IsfahanIsfahanIran Institute of Marine Sciences(ISMAR-CNR) Area Science ParkBasovizza34149 TriesteItaly National Iranian Oil Company Exploration DirectorateSheikh Bahaei SquareTehranIran Department of Geology Faculty of ScienceFerdowsi University of MashhadMashhadIran

Precise taxonomy and the chronostratigraphic calibration of the Middle Eocene Alveolina from Central Iran is here undertaken from the Chah-Talkh section of the southern Sabzevar region(Central Iran). We have identified Alveolina kieli, Alveolina stercusmuris and Alveolina nuttalli along with the new species Alveolina ozcani n. sp. that we include into the Alveolina elliptica group. We have also found Nummulites uroniensis, Nummulites obesus and Nummulites cf. verneuili and associated calcareous nannofossils that look reliable to make thoughtful correlations with the Shallow Benthic Zones(SBZ). The foraminiferal biostratigraphy suggests an assignment to the upper part of the lower Lutetian-lower part of the middle Lutetian,SBZ13(Middle Eocene), further strengthened through the identification of the calcareous nannofossil NP14b-NP15b or CNE8-CNE10 biozones, providing a solid correlation with the global stratigraphic standards.

关键词： Alveolina Calcareous nannofossil Central neo-tethys Central Iran Middle Eocene Biostratigraphy

Unveiling vulnerable smart contracts: Toward profiling vulnerable smart contracts using genetic algorithm and generating benchmark dataset

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BLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第1期5卷 58-84页

作者： HajiHosseinkhani, Sepideh Lashkari, Arash Habibi Oskui, ali Mizani York Univ Dept Comp Sci & Engn Comp Sci Toronto ON M3J1P3 Canada York Univ Behav Centr Cybersecur Ctr BCCC Sch Informat Technol Toronto ON M3J1P3 Canada Financial & Crypto Advisory Switzerland FICAS AG Zug Switzerland

Smart contracts (SCs) are crucial in maintaining trust within blockchain networks. However, existing methods for analyzing SC vulnerabilities often lack accuracy and effectiveness, while approaches based on Deep Neural Networks (DNNs) struggle with detecting complex vulnerabilities due to limited data availability. This paper proposes a novel approach for analyzing SC vulnerabilities. Our method leverages an advanced form of the Genetic Algorithm (GA) and includes the development of a comprehensive benchmark dataset consisting of 36,670 Solidity source code samples. The primary objective of our study is to profile vulnerable SCs effectively. To achieve this goal, we have devised an analyzer called SCsVulLyzer based on GAs, designed explicitly for profiling SCs. Additionally, we have carefully curated a new dataset encompassing a wide range of examples, ensuring the practical validation of our approach. Furthermore, we have established three distinct taxonomies that cover SCs, profiling techniques, and feature extraction. These taxonomies provide a systematic classification and analysis of information, improving the efficiency of our approach. Our methodology underwent rigorous testing through experimentation, and the results demonstrated the superior capabilities of our model in detecting vulnerabilities. Compared to traditional and DNN-based approaches, our approach achieved higher precision, recall, and F1 -score, which are widely used metrics for evaluating model performance. Across all these metrics, our model showed exceptional results. The customization and adaptations we implemented within the GA significantly enhanced its effectiveness. Our approach detects SC vulnerabilities more efficiently and facilitates robust exploration. These promising results highlight the potential of GA -based profiling to improve the detection of SC vulnerabilities, contributing to enhanced security in blockchain networks.

关键词： Smart contracts (SCs) Vulnerability Vulnerable smart contracts Vulnerability profiling Genetic algorithm BEHAVIOR OPTIMIZATION INFORMATION DISCOVERY KNOWLEDGE FRAMEWORK

Optimal Bidding Strategies of Microgrid with Demand Side Management for Economic Emission Dispatch Incorporating Uncertainty and Outage of Renewable Energy Sources

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Energy Engineering 2024年第4期121卷 849-867页

作者： Mousumi Basu Chitralekha Jena Baseem Khan Ahmed ali Department of Power Engineering Jadavpur UniversityJadavpurIndia School of Electrical Engineering KIIT UniversityBhubaneswarIndia Department of Electrical and Computer Engineering Hawassa UniversityHawassaEthiopia Department of Electrical and Electronic Engineering Technology Faculty of Engineering and the Built EnvironmentUniversity of JohannesburgJohannesburgSouth Africa

In the restructured electricity market,microgrid(MG),with the incorporation of smart grid technologies,distributed energy resources(DERs),a pumped-storage-hydraulic(PSH)unit,and a demand response program(DRP),is a smarter and more reliable electricity *** consists of gas turbines and renewable energy sources such as photovoltaic systems and wind *** bidding strategies,prepared by MG operators,decrease the electricity cost and emissions from upstream grid and conventional and renewable energy sources(RES).But it is inefficient due to the very high sporadic characteristics of RES and the very high outage *** solve these issues,this study suggests non-dominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ)for an optimal bidding strategy considering pumped hydroelectric energy storage and DRP based on outage conditions and uncertainties of renewable energy *** uncertainty related to solar and wind units is modeled using lognormal and Weibull probability ***-based DRP is used,especially considering the time of outages along with the time of peak loads and prices,to enhance the reliability of MG and reduce costs and emissions.

关键词： Micro-grid distributed energy resources demand response program uncertainty outage

Postpartum Hemorrhage: Incidence, Causes and Maternal Outcomes at Muhimbili National Hospital, Tanzania—A Retrospective Descriptive Hospital-Based Study

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Open Journal of Obstetrics and Gynecology 2023年第7期13卷 1244-1258页

作者： Rafiki Nickson Mjema Amani Idris Kikula Furaha August Fadhlun Alwy Al-Beity ali said Phineas F. Sospeter Nasra Batchu Benjamin Shayo Damian Jeremiah Ponsian P. Kunambi John Somi Patricia Swai Department of Obstetrics and Gynecology Muhimbili University of Health and Allied Sciences MUHAS Dar es Salaam Tanzania Department of Reproductive Maternal and Child Health Ministry of Health Dodoma Tanzania Department of Obstetrics and Gynecology Kilimanjaro Christian Medical Centre Moshi Kilimanjaro Tanzania Department of Obstetrics and Gynecology Baylor’s College Lilongwe Malawi Kilimanjaro Christian Medical University College Moshi Kilimanjaro Tanzania

Worldwide obstetric hemorrhage remains the leading cause of maternal mortality, accounting for over one quarter of maternal deaths. Over half of these deaths occur in Sub-Saharan Africa with mortality rates of 500 - 1000 per 100,000 births, compared to approximately 5 - 10 in developed countries. Over decades in Sub Saharan Africa preventive measures and treatment protocols have been made to reduce maternal mortality caused by PPH. While rates of postpartum hemorrhage have continued to rise, there is a need to evaluate if its etiology and patterns have changed over time. Broad Objective: This study aims at describing trends in incidence, causes and maternal outcomes of Postpartum Hemorrhage at Muhimbili National Hospital for a period of 7 years. Methodology: This is a retrospective descriptive hospital-based study that has included all cases of postpartum hemorrhage at Muhimbili National Hospital, a tertiary hospital in Tanzania from 2014 to 2020. The data was analyzed using SPSS Version 26 and presented using frequency tables, figures and percentages. The trends of postpartum hemorrhage over time were determined using chi-square test and P-value where less than 0.05 was considered statistically significant. Results: Overall, the incidence of postpartum hemorrhage has been fluctuating over the years with minimum of 1.78% and maximum of 2.87% with no statistical significance. Out of 1113 enrolled cases of PPH, 422 (37.9%) were attributed to genital tears followed by uterine atony 285 (25.6%). A statistically significant increase in linear trend was observed in the postpartum hemorrhage cases due to uterine atony, uterine rupture and sub analysis on genital tears (cervical tear). Overall, there was a statistically significant change in trend of maternal outcomes throughout the years, with a P-value < 0.001 and likelihood of complications increasing over time. Conclusion: The trend in the incidence of postpartum hemorrhage has been fluctuating over the years during the

关键词： Postpartum Hemorrhage Incidence Causes Maternal Outcomes and Tanzania

WebFLex:A Framework for Web Browsers-Based Peer-to-Peer Federated Learning Systems Using WebRTC

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Computers, Materials & Continua 2024年第3期78卷 4177-4204页

作者： Mai Alzamel Hamza ali Rizvi Najwa Altwaijry Isra Al-Turaiki Department of Computer Science College of Computer and Information SciencesKing Saud UniversityRiyadhKingdom of Saudi Arabia Department of Computer Science and Engineering Punjab Engineering CollegeChandigarhIndia

Scalability and information personal privacy are vital for training and deploying large-scale deep learning *** learning trains models on exclusive information by aggregating weights from various devices and taking advantage of the device-agnostic environment of web ***,relying on a main central server for internet browser-based federated systems can prohibit scalability and interfere with the training process as a result of growing client ***,information relating to the training dataset can possibly be extracted from the distributed weights,potentially reducing the privacy of the local data used for *** this research paper,we aim to investigate the challenges of scalability and data privacy to increase the efficiency of distributed training *** a result,we propose a web-federated learning exchange(WebFLex)framework,which intends to improve the decentralization of the federated learning *** is additionally developed to secure distributed and scalable federated learning systems that operate in web browsers across heterogeneous ***,WebFLex utilizes peer-to-peer interactions and secure weight exchanges utilizing browser-to-browser web real-time communication(WebRTC),efficiently preventing the need for a main central *** has actually been measured in various setups using the MNIST *** results show WebFLex’s ability to improve the scalability of federated learning systems,allowing a smooth increase in the number of participating devices without central data *** addition,WebFLex can maintain a durable federated learning procedure even when faced with device disconnections and network ***,it improves data privacy by utilizing artificial noise,which accomplishes an appropriate balance between accuracy and privacy preservation.

关键词： Federated learning web browser privacy deep learning

Simulation-based assessment for the emergency medicine milestones: a national survey of simulation experts and program directors

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World Journal of Emergency Medicine 2024年第4期15卷 301-305页

作者： Afrah A ali Ashley Crimmins Hegang Chen Danya Khoujah Department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201USA Department of Epidemiology and Public Health University of Maryland School of MedicineBaltimore 21201USA Department of Emergency Medicine AdventHealth TampaTampa 33606USA

The focus of outcome-based education has shifted from the process of training to the end“product”of *** has necessitated a reframing of the teaching,learning,and ***,in 2013,the Accreditation Council for Graduate Medical Education(ACGME)implemented the educational milestones for all accredited residencies and fellowship programs.[1]The milestones have been described as“developmentally based,specialty-specific achievements that residents are expected to demonstrate at established intervals as they progress through training.”[1]Milestones are based on the six core competencies established by the ACGME and American Board of Medical Specialties(ABMS),which consist of medical knowledge(MK),patient care(PC),interpersonal and communication skills(ICS),practice-based learning and improvement(PBLI),professionalism(PROF),and systems-based practice(SBP).[2,3]ACGME,in conjunction with the American Board of Emergency Medicine(ABEM),drafted 23 detailed subcompetencies relevant to emergency medicine(EM).[4]

关键词： Miles milestone education