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A New Formulation of the scaled Boundary Finite Element Method for Heterogeneous Media:Application to Heat Transfer Problems

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Acta Mechanica solida sinica 2024年第2期37卷 285-296页

作者： nima Noormohammadi Nazanin Pirhaji Khouzani Department of Civil Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

The solution to heat transfer problems in two-dimensional heterogeneous media is attended based on the scaled boundary finite element method(sBFEM)coupled with equilibrated basis functions(EqBFs).The sBFEM reduces the model order by scaling the boundary solution onto the inner *** this end,tri-lateral elements are emanated from a scaling center,followed by the development of a semi-analytical solution along the radial direction and a finite element solution along the circumferential/boundary *** discretization is thus limited to the boundaries of the model,and the semi-analytical radial solution is found through the solution of an eigenvalue problem,which restricts the methods’applicability to heterogeneous *** this research,we first extracted the sBFEM formulation considering the heterogeneity of the ***,we replaced the semi-analytical radial solution with the EqBFs and removed the eigenvalue solution step from the *** varying coefficients of the partial differential equation(PDE)resulting from the heterogeneity of the media are replaced by a finite series in the radial and circumferential directions of the element.A weighted residual approach is applied to the radial *** equilibrated radial solution series is used in the new formulation of the sBFEM.

关键词： scaled boundary finite element method Equilibrated basis functions Heat transfer

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 407-424页

作者： M.sAFI M.VAKILIFARD M.J.mahmoodi Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of Mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMsOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Ensemble Wind Power Prediction Interval with Optimal Reserve Requirement

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Journal of Modern Power systems and Clean Energy 2024年第1期12卷 65-76页

作者： Hamid Rezaie Cheuk Hei Chung nima safari the saskatchewan Power Corporation(saskPower) ReginaSaskatchewanCanada the Department of Electrical and Computer Engineering and Department of Human Biology University of TorontoTorontoON M5S 3G4Canada the Alberta Electric system Operator(AEsO) CalgaryAlbertaCanada

Wind power prediction interval(WPPI)models in the literature have predominantly been developed for and tested on specific case ***,wind behavior and characteristics can vary significantly across ***,a prediction model that performs well in one case might underperform in *** address this shortcoming,this paper proposes an ensemble WPPI framework that integrates multiple WPPI models with distinct characteristics to improve *** important and often overlooked factor is the role of probabilistic wind power prediction(WPP)in quantifying wind power uncertainty,which should be handled by operating *** reserve in WPPI frameworks enhances the efficacy of *** this regard,the proposed framework employs a novel bi-layer optimization approach that takes both WPPI quality and reserve requirements into *** analysis with different real-world datasets and various benchmark models validates the quality of the obtained WPPIs while resulting in more optimal reserve requirements.

关键词： Ensemble model linear programming operating reserve optimal reserve requirement prediction interval probabilistic prediction renewable integration uncertainty representation wind power prediction(WPP)

Data-driven Distributionally Adjustable Robust Chance-constrained DG Capacity Assessment

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Journal of Modern Power systems and Clean Energy 2024年第1期12卷 115-127页

作者： Masoume mahmoodi seyyed Mahdi Noori Rahim Abadi Ahmad Attarha Paul scott Lachlan Blackhall the College of Engineering and Computer science The Australian National UniversityCanberraAustralia

Moving away from fossil fuels towards renewable sources requires system operators to determine the capacity of distribution systems to safely accommodate green and distributed generation(DG).However,the DG capacity of a distribution system is often underestimated due to either overly conservative electrical demand and DG output uncertainty modelling or neglecting the recourse capability of the available *** improve the accuracy of DG capacity assessment,this paper proposes a distributionally adjustable robust chance-constrained approach that utilises uncertainty information to reduce the conservativeness of conventional robust *** proposed approach also enables fast-acting devices such as inverters to adjust to the real-time realisation of uncertainty using the adjustable robust counterpart *** achieve a tractable formulation,we first define uncertain chance constraints through distributionally robust conditional value-at-risk(CVaR),which is then reformulated into convex quadratic *** subsequently solve the resulting large-scale,yet convex,model in a distributed fashion using the alternating direction method of multipliers(ADMM).Through numerical simulations,we demonstrate that the proposed approach outperforms the adjustable robust and conventional distributionally robust approaches by up to 15%and 40%,respectively,in terms of total installed DG capacity.

关键词： Distributed generation(DG)capacity assessment distributionally robust optimisation chance-constrained optimisation distribution system

Experimental measurement and numerical modeling of deformation behavior of breast cancer cells passing through constricted microfluidic channels

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Microsystems & Nanoengineering 2024年第1期10卷 129-147页

作者： Pouyan Keshavarz Motamed Hesam Abouali Mahla Poudineh nima Maftoon Department of systems Design Engineering University of WaterlooWaterlooON N2L 3G1Canada Center for Bioengineering and Biotechnology University of WaterlooWaterlooON N2L 3G1Canada Department of Electrical and Computer Engineering University of WaterlooWaterlooON N2L 3G1Canada

During the multistep process of metastasis,cancer cells encounter various mechanical forces which make them deform *** accurate in-silico models,capable of simulating the interactions between the mechanical forces and highly deformable cancer cells,can pave the way for the development of novel diagnostic and predictive methods for metastatic ***-network models of cancer cell,empowered by our recently proposed identification approach,promises a versatile numerical tool for developing experimentally validated models that can simulate complex interactions at cellular *** this numerical tool,we presented spring-network models of breast cancer cells that can accurately replicate the experimental data of deformation behavior of the cells flowing in a fluidic domain and passing narrow constrictions comparable to ***,using high-speed imaging,we experimentally studied the deformability of breast cancer cell lines with varying metastatic potential(MCF-7(less invasive),sKBR-3(medium-high invasive),and MDA-MB-231(highly invasive)in terms of their entry time to a constricted microfluidic *** observed that MDA-MB-231,that has the highest metastatic potential,is the most deformable cell among the ***,by focusing on this cell line,experimental measurements were expanded to two more constricted microchannel *** experimental deformability data in three constricted microchannel sizes for various cell sizes,enabled accurate identification of the unknown parameters of the spring-network model of the breast cancer cell line(MDA-MB-231).Our results show that the identifed parameters depend on the cell size,suggesting the need for a systematic procedure for identifying the size-dependent parameters of spring-network models of *** the numerical results show,the presented cell models can simulate the entry process of the cell into constricted channels with very good agreements with the measured experimen

关键词： strict passing numerical

Microphysical Characteristics of Rainfall Based on Long-Term Observations with a 2DVD in Yangbajain,Tibet

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Advances in Atmospheric sciences 2024年第9期41卷 1721-1734页

作者： Ming LI Yongheng BI Yonghai sHEN Yinan WANG Ciren nima Tianlu CHEN Daren LYU Key Laboratory for Cosmic Rays of the Ministry of Education Tibet UniversityLhasa 850000China Key Laboratory of Middle Atmosphere and Global Environment Observation(LAGEO) Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China University of Chinese Academy of sciences Beijing 100049China

Raindrop size distribution(DsD)plays a crucial role in enhancing the accuracy of radar quantitative precipitation estimates in the Tibetan Plateau(TP).However,there is a notable scarcity of long-term,high-resolution observations in this *** address this issue,long-term observations from a two-dimensional video disdrometer(2DVD)were leveraged to refine the radar and satellite-based algorithms for quantifying precipitation in the hinterland of the *** was observed that weak precipitation(Rs for 86%of the total precipitation time,while small raindrops(Dse 99%of the total raindrop ***,the average spectral width of the DsD increases with increasing rain *** DsD characteristics of convective and stratiform precipitation were discussed across five different rain rates,revealing that convective precipitation in Yangbajain(YBJ)exhibits characteristics similar to maritime-like *** constrained relationships between the slopeΛand shapeμ,D_(m)and N_(w)of gamma DsDs were ***,we established a correlation between the equivalent diameter and drop axis ratio and found that raindrops on the TP attain a nearly spherical ***,the application of the rainfall retrieval algorithms of the dual-frequency precipitation radar in the TP is improved based on the statistical results of the DsD.

关键词： Tibetan Plateau raindrop size distribution 2DVD dual frequency radar microphysical features

synergistic swarm Optimization Algorithm

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Computer Modeling in Engineering & sciences 2024年第6期139卷 2557-2604页

作者： sharaf Alzoubi Laith Abualigah Mohamed sharaf Mohammad sh.Daoud nima Khodadadi Heming Jia Faculty of Computer sciences and Informatics Amman Arab UniversityAmman11953Jordan Computer science Department Al Al-Bayt UniversityMafraq25113Jordan Department of Electrical and Computer Engineering Lebanese American UniversityByblos13-5053Lebanon Hourani Center for Applied scientific Research Al-Ahliyya Amman UniversityAmman19328Jordan MEU Research Unit Middle East UniversityAmman11831Jordan Applied science Research Center Applied Science Private UniversityAmman11931Jordan school of Computer sciences Universiti Sains MalaysiaPulau Pinang11800Malaysia school of Engineering and Technology Sunway University MalaysiaPetaling Jaya27500Malaysia Department of Industrial Engineering College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia College of Engineering Al Ain UniversityAbu Dhabi112612United Arab Emirates Department of Civil and Architectural Engineering University of MiamiCoral Gables1251USA school of Information Engineering Sanming UniversitySanming365004China

This research paper presents a novel optimization method called the synergistic swarm Optimization Algorithm(ssOA).The ssOA combines the principles of swarmintelligence and synergistic cooperation to search for optimal solutions efficiently.A synergistic cooperation mechanism is employed,where particles exchange information and learn from each other to improve their search *** cooperation enhances the exploitation of promising regions in the search space while maintaining exploration ***,adaptive mechanisms,such as dynamic parameter adjustment and diversification strategies,are incorporated to balance exploration and *** leveraging the collaborative nature of swarm intelligence and integrating synergistic cooperation,the ssOAmethod aims to achieve superior convergence speed and solution quality performance compared to other optimization *** effectiveness of the proposed ssOA is investigated in solving the 23 benchmark functions and various engineering design *** experimental results highlight the effectiveness and potential of the ssOA method in addressing challenging optimization problems,making it a promising tool for a wide range of applications in engineering and *** codes of ssOA are available at:https://***/matlabcentral/fileexchange/153466-synergistic-swarm-optimization-algorithm.

关键词： synergistic swarm optimization algorithm optimization algorithm metaheuristic engineering problems benchmark functions

Nurses'attitude toward patients'safety climate during COVID-19 pandemic:a cross-sectional study

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Frontiers of Nursing 2024年第1期11卷 39-46页

作者： Asra Nassehi Kobra Ghorbanzadeh somaye Moayedi Javad Jafari Parvin mahmoodi Mojtaba Jafari Department of Nursing Bam University of Medical SciencesBamIran Department of Nursing Khalkhal University of Medical SciencesKhalkhalIran Community Nursing Research Center Department of NursingZahedan University of Medical SciencesZahedanIran Clinical Care Research Center Department of NursingNursing and Midwifery SchoolKurdistan University of Medical SciencesSanandajIran

Objective:Patient safety is a fundamental factor in improving the quality of care provided in ***,it is considered a significant parameter by all healthcare organizations around the *** present study was conducted to investigate the attitude of nurses toward the patient safety climate during the Coronavirus Disease 2019(COVID-19)pandemic in the southeast of ***:This is a cross-sectional descriptive *** all the nurses working in one of the hospitals in the southeast of Iran,171 nurses participated in the study through convenience sampling *** survey was conducted between June 1 and July 30,2020.A 2-part questionnaire including demographic information and an assessment of nurses'attitudes toward patients'safety climate was used for data collection in *** content validity of the scale is(0.77)and reliability was re-calculated and confirmed by the present study with Cronbach's alpha(α=0.9).Data were analyzed by sPss 20(IBM Corporation,Armonk,New York,United states)using descriptive and analytical statistical ***:The mean score of safety climates was 3.2±5.20(out of 5 scores).The results showed that among all dimensions of the safety climate,only the education dimension was statistically significant between males and females(Pso,there was a significant relationship between the overall average of the safety climate and its dimensions according to the people's position only in the dimension of supervisors'attitude(Psignificant correlation between the education level and the overall score of safety climate(Ps well as the supervisor's attitude dimension(Ps ***:The results showed that the safety climate was at a relatively favorable *** the impact of nurses'attitudes on the safety climate of patients,its improvement seems *** is recommended to design training courses and educate nurses in order to promote a p

关键词： COVID-19 Iran nurses patient safety climate

Propofol sedation in routine endoscopy:A case series comparing target controlled infusion vs manually controlled bolus concept

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World Journal of Gastrointestinal Endoscopy 2024年第1期16卷 11-17页

作者： Riad sarraj Lorenz Theiler nima Vakilzadeh Niklas Krupka Reiner Wiest Department of Visceral surgery and Medicine Inselspital University HospitalBern 3010Switzerland Clinic for Anesthesia PerioperativeEmergency&Intensive Care MedicineKantonsspital AarauAarau 5001Switzerland Department of Nephrology and Hypertension University Hospital LausanneLausanne 1011Switzerland

BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPs)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedation regimen by avoiding under-or *** To assess safety and performance of propofol TCI sedation in comparison with nurse-administered *** Fouty-five patients undergoing endoscopy under TCI propofol sedation were prospectively included from November 2016 to May 2017 and compared to 87 patients retrospectively included that underwent endoscopy with *** were matched for age and endoscopic *** recorded time of sedation and endoscopy,dosage of medication and adverse *** There was a significant reduction in dose per time of propofol administered in the TCI group,compared to the NAPs group(8.2±2.7 mg/min vs 9.3±3.4 mg/min;P=0.046).The time needed to provide adequate sedation levels was slightly but significantly lower in the control group(5.3±2.7 min vs 7.7±3.3 min;Pss the total endoscopy time was similar in both *** differences between TCI and bolus-sedation was observed for mean total-dosage of propofol rate as well as adverse *** This study indicates that sedation using TCI for GI endoscopy reduces the dose of propofol necessary per minute of *** may translate into less adverse ***,further and randomized trials need to confirm this trend.

关键词： sedation Endoscopy Propofol Target controlled infusion Non-anaesthesiologist propofol sedation Adverse event