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Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA Y.V.OSIPOV A.R.PESTEREV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case.of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

Control Policy learning Design for Vehicle Urban Positioning via BeiDou Navigation

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Journal of Systems Science & Complexity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci XIE Shengli lEWIS Frank l School of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key laboratory of IoT Information Technology Guangzhou 510006China. Center for Intelligent Batch Manufacturing Based on IoT Technology Key laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint laboratory for Smart Discrete Manufacturing Guangzhou 510006China Key laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a learning-based control policy design for point-to-point vehicle positioning in the urban environment via BeiDou *** navigating in urban canyons,the multipath effect is a kind of interference that causes the navigation signal to drift and thus imposes severe impacts on vehicle localization due to the reflection and diffraction of the BeiDou ***,the authors formulated the navigation control system with unknown vehicle dynamics into an optimal control-seeking problem through a linear discrete-time system,and the point-to-point localization control is modeled and handled by leveraging off-policy reinforcement learning for feedback *** proposed learning-based design guarantees optimality with prescribed performance and also stabilizes the closed-loop navigation system,without the full knowledge of the vehicle *** is seen that the proposed method can withstand the impact of the multipath effect while satisfying the prescribed convergence rate.A case.study demonstrates that the proposed algorithms effectively drive the vehicle to a desired setpoint under the multipath effect introduced by actual experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation multipath effect prescribed convergence rate reinforcement learning urban localization.

Zassenhaus lemma,Schreier Refinement Theorem,and Jordan–Hölder Theorem for Gyrogroups

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Algebra Colloquium 2024年第2期31卷 323-332页

作者： Prathomjit Khachorncharoenkul Rasimate Maungchang Teerapong Suksumran l.A.Bokut School of Science Walailak UniversityNakhon Si Thammarat 80160Thailand Department of Mathematics Faculty of ScienceChiang Mai University Chiang Mai 50200Thailand 不详

In this article,we extend the Zassenhaus lemma(also called the butterfly lemma)and the Schreier refinement theorem to the case.of *** addition,we use these results to prove the Jordan–Hölder theorem for gyrogroups as... 详细信息

关键词： Zassenhaus lemma Schreier refinement theoremg yrogroup subgyrogroup diagram normal subgyrogroup

A review of whole-medical systems and holistic care approach for type 2 diabetes and associated metabolic syndrome

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Journal of Integrative Medicine 2024年第3期22卷 199-209页

作者： loveness Makoni Idah T.Manduna Alaisa l.Mbiriri Department of Health Sciences Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Centre for Applied Food Sustainability and Biotechnology(CAFSaB) Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Adventist Development and Relief Agency(ADRA) 5 Cecil RoadGreendaleHarare 0000Zimbabwe

Whole-person care and holistic care approach has been proposed for complementary and integrative health care for type 2 diabetes ***,some doubts still exist on the feasibility of replicating processes followed in clinical trials and observational studies in real-world *** narrative literature review summarized and assessed existing clinical evidence(clinical trials,observational studies,and case.reports)describing holistic and integrated care approach in adult and adolescent individuals with type 2 diabetes mellitus in clinical *** goal was to highlight existing evidence for implementation and outcomes of whole-medical systems and holistic integrated care approach for type 2 diabetes mellitus.A nonsystematic literature search was performed on Google Scholar,PubMed,Web of Science,ProQuest and ScienceDirect to identify clinical evidence from different parts of the world,evaluating the use of whole-medical systems and/or holistic care interventions in clinical practice for management of type 2 diabetes *** keywords were used in the *** were analyzed using content analysis and simple descriptive statistics(percentages).Most of the studies(64%)were mainly conducted in Eastern countries(India,China and Israel)while 36%of the studies were conducted in the Western countries(USA,Netherlands,Canada and Mexico).lifestyle medicine and integrated naturopathy were shown to be the commonly used whole-medical systems for type 2 diabetes mellitus *** improvements in type 2 diabetes parameters,medication use,other symptoms,and overall feeling of wellness were observed in all *** review study revealed limited utilization and/or documentation of whole-medical systems or holistic care treatments for type 2 diabetes mellitus in regions of the world other than eastern *** medicine,naturopathy,yoga,Ayurveda and traditional Chinese medicine were shown to be effective for type 2 diabetes mellitu

关键词： Complementary and alternative medicine Holistic care Integrative medicine Type 2 diabetes mellitus Team-based intervention

Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study

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Particuology 2024年第7期90卷 364-382页

作者： Barış Gürel Gülşah Karaca Dolgun Osman İpek Ali Keçebaş Department of Mechanical Engineering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energy Systems Engineering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key ***,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case.of GlI-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole *** NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and ***,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.

关键词： Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency

Robust Machine learning Mapping of sEMG Signals to Future Actuator Commands in Biomechatronic Devices

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Journal of Bionic Engineering 2024年第1期21卷 270-287页

作者： Ali Nasr Sydney Bell Rachel l.Whittaker Clark R.Dickerson John McPhee Systems Design Engineering University of WaterlooWaterloo N2L 3G1Canada Kinesiology and Health Sciences University of WaterlooWaterloo N2L3G3Canada

A machine learning model for regression of interrupted Surface Electromyography(sEMG)signals to future control-oriented signals(e.g.,robot’s joint angle and assistive torque)of an active biomechatronic device for high-level myoelectric-based hierarchical control is proposed.A Recurrent Neural Network(RNN)was trained using output data,initially obtained from offline optimization of the biomechatronic(human–robot)device and shifted by the prediction *** input of the RNN consisted of interrupted sEMG signals(to mimic signal disconnections)and previous kinematic signals of the assistive *** RNN with a 0.1-s prediction horizon could predict the control-oriented joint angle and assistive torque with 92%and 86.5%regression accuracy,respectively,for the test *** proposed approach permits a fast,predictive,and direct estimation of control-oriented signals instead of an iterative process that optimizes assistive torque in the inverse dynamic simulation of a multibody human–robot *** with these interrupted input signals significantly improves the regression accuracy in the case.of sEMG signal *** Robust Predictive Control-oriented Machine learning(Robust-MuscleNET)model can support volitional high-level myoelectric-based control of biomechatronic devices,such as exoskeletons,prostheses,and assistive/resistive *** work should study the application to prosthesis control as well as the repeatability of the high-level controller with electrode *** low-level hierarchical controller that manages the human–robot interaction,the assistance/resistance strategy,and the actuator coordination should also be studied.

关键词： Myoelectric-based control-Surface electromyography Machine learning Multibody system dynamics Exoskeleton Bionic

GRB 210323A:Signature of long-lasting lifetime of Supra-massive Magnetar as the Central Engine from the Merger of Binary Neutron Star

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Research in Astronomy and Astrophysics 2024年第8期24卷 32-41页

作者： Yingze Shan Xiaoxuan liu Xing Yang Haoyu Yuan Houjun lü Guangxi Key laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China

Theoretically,a supra-massive neutron star or magnetar may be formed after the merger of binary neutron ***210323A is a short-duration gamma-ray burst(GRB)with a duration of lasting~1 *** light curve of the prompt emission of GRB 210323A shows a signal-peaked structure and a cutoff power-law model can adequately fit the spectra with E_p=1826±*** interestingly,it has an extremely long-lasting plateau emission in the X-ray afterglow with a duration of~10^(4)s,and then follows a rapid decay with a decay slope~*** temporal feature is challenging by invoking the external shock *** this paper,we suggest that the observed long-lasting X-ray plateau emission is caused by the energy injection of dipole radiation from supra-massive magnetar,and the abrupt decay following the longlasting X-ray plateau emission is explained by supra-massive magnetar collapsing into a black *** is the short GRB(SGRB)with the longest X-ray internal plateau emission powered by a supra-massive neutron *** this is the case.one can estimate the physical parameters of a supra-massive magnetar,and compare with other *** also discuss the possible gravitational-wave emission,which is powered by a supra-massive magnetar and its detectability,and the possible kilonova emission,which is powered by r-process and magnetar spin-down to compare with the observed data.

关键词： (stars)gamma-ray burst general-(stars)gamma-ray burst individual(GRB 210323A)-stars magnetars

Pancreatic surgery and tertiary pancreatitis services warrant provision for support from a specialist diabetes team

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World Journal of Diabetes 2024年第4期15卷 598-605页

作者： Vasileios K Mavroeidis Jennifer Knapton Francesca Saffioti Daniel l Morganstein Department of HPB Surgery Bristol Royal InfirmaryUniversity Hospitals Bristol and Weston NHS Foundation TrustBristol BS28HWUnited Kingdom Department of Gastrointestinal Surgery Southmead HospitalNorth Bristol NHS TrustBristol BS105NBUnited Kingdom Department of Academic Surgery Royal Marsden NHS Foundation TrustLondon SW36JJUnited Kingdom Department of Gastroenterology and Hepatology Oxford University Hospitals NHS Foundation TrustOxford OX39DUUnited Kingdom UCl Institute for liver and Digestive Health University College LondonLondon NW32PFUnited Kingdom Department of Endocrinology Chelsea and Westminster Hospital NHS Foundation TrustLondon SW109NHUnited Kingdom Department of Gastrointestinal Unit Royal Marsden NHS Foundation TrustLondon SW36JJUnited Kingdom

Pancreatic surgery units undertake several complex operations,albeit with consi-derable morbidity and mortality,as is the case.for the management of complicated acute pancreatitis or chronic *** centralisation of pancreatic surgery services,with the development of designated large-volume centres,has contribu-ted to significantly improved *** this editorial,we discuss the complex associations between diabetes mellitus(DM)and pancreatic/periampullary disease in the context of pancreatic surgery and overall management of complex pancreatitis,highlighting the consequential needs and the indispensable role of specialist diabetes teams in support of tertiary pancreatic *** 3c pan-creatogenic DM,refers to DM developing in the setting of exocrine pancreatic disease,and its identification and management can be challenging,while the glycaemic control of such patients may affect their course of treatment and *** preoperative diabetes assessment is warranted to aid identification of patients who are likely to need commencement or escalation of glucose lowering therapy in the postoperative *** incidence of new onset diabetes after pancreatic resection is widely variable in the literature,and depends on the type and extent of pancreatic resection,as is the case.with pancreatic parenchymal loss in the context of severe *** involvement of a specialist diabetes team is essential to ensure a holistic *** the current era,large volume pancreatic surgery services commonly abide by the principles of enhanced recovery after surgery,with inclusion of provisions for optimisation of the perioperative glycaemic control,to improve *** various guidelines are available to aid perioperative management of DM,auditing and quality improvement platforms have highlighted deficiencies in the perioperative management of diabetic patients and areas of required *** need for perioperative support of diabetic

关键词： Pancreatectomy Pancreatoduodenectomy Whipple’s Pancreatitis Diabetes specialist Type 3c pancreatogenic diabetes mellitus