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Variational Iterative Method Applied to Variational Problems with Moving Boundaries

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Applied Mathematics 2012年第5期3卷 395-402页

作者： Fateme Ghomanjani sara ghaderi Department of Applied Mathematics Ferdowsi University of Mashhad Mashhad Iran

In this paper, He’s variational iterative method has been applied to give exact solution of the Euler Lagrange equation which arises from the variational problems with moving boundaries and isoperimetric problems. In this method, general Lagrange multipliers are introduced to construct correction functional for the variational problems. The initial approximations can be freely chosen with possible unknown constant, which can be determined by imposing the boundary conditions. Illustrative examples have been presented to demonstrate the efficiency and applicability of the variational iterative method.

关键词： Variational Iterative Method Variational Problems Moving Boundaries Isoperimetric Problems

Solving the Optimal Control of Linear Systems via Homotopy Perturbation Method

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Intelligent Control and Automation 2012年第1期3卷 26-33页

作者： Fateme Ghomanjani sara ghaderi Mohammad Hadi Farahi Department of Applied Mathematics Ferdowsi University of Mashhad Mashhad Iran

In this paper, Homotopy perturbation method is used to find the approximate solution of the optimal control of linear systems. In this method the initial approximations are freely chosen, and a Homotopy is constructed with an embedding parameter , which is considered as a “small parameter”. Some examples are given in order to find the approximate solution and verify the efficiency of the proposed method.

关键词： Homotopy Perturbation Method Optimal Control Problem Hamilton System

Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： sara Marijan Luka Pavic Division of Materials Chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 *** transition from a predominantly phosphate glass network(x<10,region I)to a mixed niobate–phosphate glass net-work(10≤x≤20,region II)leads to an increase in the dielectric parameters,which correlates with the observed trend in the direct-cur-rent(DC)*** the predominantly niobate network(x≥25,region III),the highly polarizable nature of Nb5+ions leads to a fur-ther increase in the dielectric permittivity and dielectric *** is particularly evident in Nb-40 glass-ceramic,which contains Na_(13)Nb_(35)O_(94) crystalline phase with a tungsten bronze structure and exhibits the highest dielectric permittivity of 61.81 and the lowest loss factor of 0.032 at 303 K and 10 *** relaxation studies,analyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic *** contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation *** high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)*** scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism

Advancements in Barrett's esophagus detection:The role of artificial intelligence and its implications

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World Journal of Gastroenterology 2024年第11期30卷 1494-1496页

作者： sara Massironi Division of Gastroenterology and Center for Autoimmune Liver Diseases Department of Medicine and SurgeryFondazione IRCCS San Gerardo dei TintoriUniversity of Milano-BicoccaMonza 20900Italy

Artificial intelligence(AI)is making significant strides in revolutionizing the detection of Barrett's esophagus(BE),a precursor to esophageal *** the research article by Tsai et al,researchers utilized endoscopic images to train an AI model,challenging the traditional distinction between endoscopic and histological *** approach yielded remarkable results,with the AI system achieving an accuracy of 94.37%,sensitivity of 94.29%,and specificity of 94.44%.The study's extensive dataset enhances the AI model's practicality,offering valuable support to endoscopists by minimizing unnecessary ***,questions about the applicability to different endoscopic systems *** study underscores the potential of AI in BE detection while highlighting the need for further research to assess its adaptability to diverse clinical settings.

关键词： Barrett's esophagus Artificial intelligence Endoscopic images Artificial intelligence model Early cancer detection Endoscopy

Experimental evaluation of mechanical compression of lattice trusses made with Ti6Al4V for aerospace use

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Chinese Journal of Aeronautics 2024年第5期37卷 520-532页

作者： Carlo Giovanni FERRO sara VARETTI Paolo MAGGIORE Department of Mechanical and Aerospace Engineering Politecnico di TorinoCorso Duca degli AbruzziTorino 10124Italy

Lattice structures are three-dimensional structures composed of repeated geometrical shapes with multiple interconnected nodes,providing high strength-to-weight ratios,customizable properties,and efficient use of materials.A smart use of materials leads to reduced fuel consumption and lower operating costs,making them highly desirable for aircraft ***,the customizable properties of lattice structures allow for tailoring to specific design requirements,leading to improved performance and safety for *** advantages make lattice structures an important focus for research and development in the aviation *** paper presents an experimental evaluation of the mechanical compression properties of lattice trusses made with Ti6Al4V,designed for use in an anti-ice *** truss structures were manufactured using additive manufacturing techniques and tested under compressive loads to determine mechanical *** showed that lattice trusses exhibited high levels of compressive strength,making them suitable for use in applications where mechanical resistance and durability are critical,such as in anti-ice *** also highlight the potential of additive manufacturing techniques for the fabrication of lattice trusses with tailored mechanical *** study provides valuable insights into the mechanical behavior of Ti6Al4V lattice trusses and their potential applications in anti-ice systems,as well as other areas where high strength-to-weight ratios are *** results of this research contribute to the development of lightweight,efficient,and durable anti-ice systems for use in aviation and other industries.

关键词： Additive Manufacturing(AM) Selective Laser Sintering(SLM) Anti ice systems Lattice structures Aircraft on board systems Design of Experiments(DOE)

Interpreting siliciclastic sedimentation in the upper Paleozoic Mulargia-Escalaplano Basin(Sardinia, Italy):influence of tectonics on provenance

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Journal of Palaeogeography 2024年第1期13卷 18-34页

作者： Luca G.Costamagna sara Criniti Dipartimento di Scienze Chimiche e Geologiche Citadella UniversitariaBlocco A09042 Monserrato CAItaly Dipartimento di Ingegneria dell'Ambiente Universita della Calabria87036 Arcavacata di Rende CSItaly

Late to post-Variscan molassic basins of Late Pennsylvanian-Permian age are exposed in Sardinia(Italy). Here, the compositional and stratigraphic evolution of the Mulargia-Escalaplano sedimentary basin(central Sardinia) has been investigated to highlight how the tectono-magmatic processes have influenced the sedimentation. Ruditic and arenitic samples were collected along well-characterized stratigraphic sections to provide a new insight into the impact of the tectono-magmatic processes on siliciclastic sedimentation. As a result, the conglomerates are mainly clast-supported, petromictic, and thus immature, with no defined maturity trend upwards. Nevertheless, pebble composition changes in times from Variscan basement pebble-rich to volcanic rock-rich, as a consequence of the basin widening and the dismantling and reworking of the coeval volcanic activity. The sandstone composition clearly changes from quartzolithic to feldspatholithic upwards, as a response to the same change of feeding and reworking of the volcanic rocks. Occasionally, interbedded quartzolithic arenites suggest exceptional floods carrying debris from the far borders of the basin. Also, the immature sandstone composition has been interpreted as being controlled by a continuous supply of fresh debris and to a rapid burial rate. In addition, the disappearance of metaradiolarite(lydite AA) Paleozoic grains in the sandstone mineral suite could represent a distinctive marker of a progressive unroofing of the Variscan chain and a clastic supply from deeper tectonic units.

关键词： Petrography Stratigraphy Provenance Molassic basins Sardinia

Fault detection of new and aged lithium-ion battery cells in electric vehicles

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Green Energy and Intelligent Transportation 2024年第3期3卷 42-53页

作者： sara Sepasiahooyi Farzaneh Abdollahi Department of Electrical Engineering Amirkabir University of Technology(Tehran Polytechnic)424 Hafez AveTehranIran Department of Mechanical Engineering Texas Tech UniversityLubbockTXUSA Department of Mechanical and Aerospace Engineering Carleton UniversityOttawaONCanada

In this paper,a novel model-based fault detection in the battery management system of an electric vehicle is *** adaptive observers are designed to detect state-of-charge faults and voltage sensor faults,considering the impact of battery *** aging primarily affects capacity and resistance,becoming more pronounced in the later stages of a battery *** incorporating aging effects into our fault diagnosis scheme,our proposed approach prevents false or missed alarms for the aged battery *** aging effect of battery,capacity fading and resistance growth,are considered unknown *** adaptive observer is employed to design a fault detector,considering unknown parameters in the battery *** adaptive observers are designed for two different scenarios:In the first scenario,it is presumed that aging effects remain constant over time due to their slow rate of ***,it is assumed that aging effects are ***,the fault detection scheme can detect faults of new battery cells as well as aged *** simulations have been conducted on a Lithium-ion battery cell and extended to battery pack,to demonstrate the performance of the proposed approach in more real-world *** results showed that the designed observers can detect faults correctly in a seven years old battery as well as a new one.

关键词： Adaptive observer Aging Electric vehicle Fault detection Lithium-ion battery State of charge

Changes in Metabolites and Allelopathic Effects of Non-Pigmented and Black-Pigmented Lowland Indica Rice Varieties in Phosphorus Deficiency

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Rice science 2024年第4期31卷 434-448,I0025,I0026页

作者： Liyana sara Sompop SAEHENG Panupong PUTTARAK Lompong KLINNAWEE Division of Biological Science Faculty of SciencePrince of Songkla UniversitySongkhla 90110Thailand Division of Health and Applied Sciences Faculty of SciencePrince of Songkla UniversitySongkhla 90110Thailand Plant Cell and Physiology for Sustainable Agriculture Research Unit Faculty of SciencePrince of Songkla UniversitySongkhla 90110Thailand Department of Pharmacognosy and Pharmaceutical Botany Faculty of Pharmaceutical SciencesPrince of Songkla UniversitySongkhla 90110Thailand Phytomedicine and Pharmaceutical Biotechnology Excellence Center Prince of Songkla UniversitySongkhla 90110Thailand

Phosphorus(P) levels alter the allelopathic activity of rice seedlings against lettuce seeds. In this study, we investigated the effect of P deficiency on the allelopathic potential of non-pigmented and pigmented rice varieties. Rice seedlings of the white variety Khao Dawk Mali(KDML105, non-pigmented) and the black varieties Jao Hom Nin(JHN, pigmented) and Riceberry(RB, pigmented) were cultivated under high P(HP) and low P(LP) conditions. Morphological and metabolic responses to P deficiency were investigated. P deficiency inhibited shoot growth but promoted root growth of rice seedlings in all three varieties. Moreover, P deficiency led to decreased cytosolic phosphate(Pi) and total P concentrations in both shoot and root tissues. The subsequent reduction in internal P concentration enhanced the accumulation of phenolic compounds in both shoot and root tissues of the seedlings. Subsequently, allelopathy-based inter-and intra-specific interactions were assessed using water extracts from seedlings of the three varieties grown under HP and LP conditions. These extracts were tested on seeds of lettuce, the weed Dactyloctenium aegyptium, and the same rice variety. The shoot and root extracts from P-deficient seedlings reduced the germination of all recipient plants. Specifically, the shoot extract from P-deficient KDML105 seedlings reduced the germination index(GI) of lettuce seeds to 1%, while those from P-deficient RB and JHN seedlings produced GIs of 32% and 42%, respectively. However, when rice seeds were exposed to their own LP shoot and root extracts, their GIs increased up to 4-fold, compared with the HP extracts. Additionally, the shoot extracts from P-deficient plants also stimulated the germination of D. aegyptium by about 2–3-fold, whereas the root extracts did not have this effect. Therefore, P starvation led to the accumulation and exudation of phenolics in the shoots and roots of rice seedlings, altering their allelopathic activities. To adapt to P defici

关键词： phosphorus deficiency non-pigmented and black-pigmented rice phenolics extract allelopathy

Advancing hepatic recompensation:Baveno VII criteria and therapeutic innovations in liver cirrhosis management

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World Journal of Gastroenterology 2024年第23期30卷 2954-2958页

作者： Lorenzo Ridola sara Del Cioppo Department of Medical and Surgical Sciences and Biotechnologies Sapienza University of RomePolo PontinoRome 00185Italy

The Baveno VII criteria redefine the management of decompensated liver cirrhosis,introducing the concept of hepatic recompensation marking a significant departure from the conventional view of irreversible *** to this concept is addressing the underlying cause of cirrhosis through tailored therapies,including antivirals and lifestyle *** on alcohol,hepatitis C virus,and hepatitis B virus-related cirrhosis demonstrate the efficacy of these interventions in improving liver function and patient *** intrahepatic portosystemic shunt(TIPS)emerges as a promising intervention,effectively resolving complications of portal hypertension and facilitating ***,optimal timing and patient selection for TIPS remain *** challenges,TIPS offers renewed hope for hepatic recompensation,marking a significant advancement in cirrhosis *** research is needed to refine its implementation and maximize its *** conclusion,TIPS stands as a promising avenue for improving hepatic function and patient outcomes in decompensated liver cirrhosis within the framework of the Baveno VII criteria.

关键词： Hepatic recompensation Baveno VII Transjugular intrahepatic portosystemic shunt Portal hypertension Cirrhosis Decompensation