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Applied mathematics and mechanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHmAN m.TURKYILmAZOGLU Z.mUSHTAQ Department of mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,m=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Theory of Flexural Shear, Bending and Torsion for a Thin-walled Beam of Open Section

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world Journal of mechanics 2024年第3期14卷 23-53页

作者： David w. A. Rees Abdelraouf m. Sami Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress

关键词： Thin wall Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow warping Fixed-End Constraint

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.D.Hossain m.S.Sikder m.N.I.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Double compound combination synchronization among eight n-dimensional chaotic systems

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Chinese Physics B 2018年第8期27卷 150-158页

作者： Gamal m mahmoud Tarek m abed-Elhameed Ahmed A Farghaly Department of mathematics Faculty of Science Assiut University

Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization （DCCS） of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the mATLAB simula- tion outcomes. we obtain the same results of numerical treatment of our synchronization using simulation observations of our example.

关键词： double compound synchronization compound combination synchronization chaotic system Lya-punov stability

Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 Hz-3 mHz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

A Dynamic Network Game of the Fintech Industry

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Journal of the Operations Research Society of China 2024年第1期12卷 5-33页

作者： David w.K.Yeung Leon A.Petrosyan Ying-Xuan Zhang SRS Consortium for Advanced Study in Cooperative Dynamic Games Shue Yan UniversityHong KongChina Center of Game Theory St Petersburg State UniversitySaint PetersburgRussia Department of Finance Asia UniversityTaichung CityTaiwanChina Faculty of Applied mathematics-Control Processes and Center of Game Theory St Petersburg StateUniversitySaint PetersburgRussia

Economies of scale,economies of scope,and technology spillover are decisive eco-nomic elements that are crucial to the development in the Fintech *** externalities are often realized through network *** this paper,we presenta dynamic network ofﬁnancialﬁrms which exhibits these decisive *** game equilibria are characterized.A Pareto efﬁcient solution involving col-laboration of allﬁrms is *** obtain a fair-share distribution of cooperativegains,the Shapley value is adopted as the sharing *** distributionmechanisms which guarantee the fulﬁlment of the Shapley value distribution in eachstage of the cooperation duration are derived.

关键词： Network game Network equilibria Shapley value Pareto efﬁcientcooperation

Strategies for Dissecting the Genetic Driving of Conserved Noncoding-Elements for Evolutionary Development of the Corpus Callosum

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Neuroscience Bulletin 2024年第7期40卷 1025-1027页

作者： Yaxin Ye Boxing Jin Hao w.Zhang Nengyin Sheng State Key Laboratory of Genetic Resources and Evolution Key Laboratory of Animal Models and Human Disease Mechanisms of Yunnan ProvinceKunming Institute of ZoologyChinese Academy of SciencesKunming 650201China Kunming College of Life Science University of Chinese Academy of SciencesKunming 650201China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming 650201China

with the efforts in developmental biology and neuroscience during the past several decades,our knowledge has been significantly advanced about the genetic,cellular,and molecular mechanisms underlying brain development and ***,we should keep in mind that the human brain is the product of complex evolutionary processes,and there is a trade-off between brain evolution and neurological disorders[1].

关键词： function. neurological knowledge

Strategic Planning Practices of Hotels in Kenya

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Journal of Tourism and Hospitality management 2024年第1期12卷 12-17页

作者： Lilian m.Gikutha Florence w.Njau Naghea Jilo Kenya Utalii College NairobiKenya

This study broadens perspectives of strategic planning procedures in hotels by analyzing hotel managers’perspectives on hotel strategy formulation and *** study was a descriptive quantitative study that targeted managers from various Kenyan hotels.180 questionnaires were returned from a sample of 280 hotel managers who had attended management development programs at a hospitality *** primary goal of the study was to analyze two aspects of the strategic planning process:strategy formulation and strategic *** findings revealed that hotels in Kenya have developed methods and are keen on scanning their external ***,with the product offerings being so comparable,competitive analysis played an important role in the *** a unique or specialty offering was not a popular option for most ***-cutting was the most favored strategic inclination to achieve desired *** balanced scorecard was underutilized in the *** managers were involved in the strategic planning process,other lower cadre employees were not,they were provided with the targets for the hotels’organizational goals to be *** findings reveal that with similar products and services,the industry creates a hostile business climate with fierce rivalry and must invest in the most obvious alternative of cost reduction to *** product innovation is not common in this industry for developing a differentiation approach that allows a property to control a market.

关键词： hotels strategy formulation strategic planning

Liver transplantation as an alternative for the treatment of intrahepatic cholangiocarcinoma: Past, present, and future directions

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 129-138页

作者： Sudha Kodali Ashton A Connor Souhail Thabet Elizabeth w Brombosz R mark Ghobrial Sherrie and Alan Conover Center for Liver Disease and Transplantation Houston Methodist HospitalHoustonTX 77030USA JC walter Jr Transplant Center Houston Methodist HospitalHoustonTX 77030USA Department of medicine Weill Cornell Medical CollegeNew YorkNYUSA Department of Surgery Houston Methodist HospitalHoustonTX 77030USA Department of Surgery Weill Cornell Medical CollegeNew YorkNYUSA School of medicine New Giza UniversityGizaEgypt

Intrahepatic cholangiocarcinoma(iCCA)is a rare biliary tract cancer with high mortality *** resection of the iCCA lesion is the first choice of treatment,with good prognosis after margin-negative ***,only 12%-40% of patients are eligible for resection at presentation due to cirrhosis,portal hypertension,or large tumor *** transplantation(LT)offers margin-negative iCCA extirpation for patients with unresectable ***,iCCA was a contraindication for LT until size-based selection criteria were introduced to identify patients with satisfied post-LT *** studies have shown that tumor biology-based selection can yield high post-LT survival in patients with locally advanced *** selection criterion is the tumor response to neoadjuvant *** with response to neoadjuvant therapy have better outcomes after LT compared with those without tumor response to neoadjuvant *** index that helps predict the treatment outcome is the *** survival outcomes have also opened the door for living donor LT for *** undergoing LT for iCCA now have statistically similar survival rates as patients undergoing *** combination of surgery and locoregional and systemic therapies improves the prognosis of iCCA patients.

关键词： Liver transplantation Cholangiocarcinoma Hepatectomy Transplant oncology Liver neoplasm

Braneworld black holes with modmax electrodynamics on the brane

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Communications in Theoretical Physics 2024年第6期76卷 120-128页

作者： Haryanto m Siahaan Jurusan Fisika Universitas Katolik ParahyanganJalan Ciumbuleuit 94Bandung 40141Indonesia

In this study,we investigate modmax electrodynamics localized within the Randall-Sundrum Ⅱ and Dvali-Gabadadze-Porrati branes,deriving corresponding 3-brane spacetime solutions that conform to the effective Einstein equations in each specific *** construct solutions for charged black holes within the effective Einstein equation framework in both braneworld *** examination explores the trajectories of charged objects in this spacetime,underscoring the significance of the nonlinear *** analysis uncovers the fact that,similar to the prior modmax black hole investigation,the nonlinear parameter plays a pivotal role in suppressing the effective charge of the black hole,due to its definite positive value.

关键词： RS-II DGP modmax brane