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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)w.th a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,w.re examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy w.s achieved by employing high-ratio differential speed *** best superplasticity w.s achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),w.ere tensile elongations of 550±600%w.re *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size w.s observed at temperatures above 573 ***,it w.s important to consider this effect w.en analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow.at low.strain rates w.s governed by lattice diffusion-controlled grain boundary sliding,w.ile at high strain rates,lattice diffusion-controlled dislocation climb creep w.s the rate-controlling deformation *** w.s concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it w.s observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps w.re constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain grow.h

The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-w.lled Cantilever Channel Beam

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w.rld Journal of Mechanics 2024年第5期14卷 73-96页

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

Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers w.th x-axis symmetry. The flexural bending and shear that arise w.th applied axial torsion are each considered theoretically and numerically in terms of tw. longitudinal axes of loading not coincident w.th the shear centre. In particular, the w.rping displacements, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its w.b centre. The stress conversions derived from each action are superimposed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established compared to previous results for each beam w.en loading is referred to a flexural axis through the shear centre. w.thin the net stress analysis is, it is show. how.the constraint to free w.rping presented by the end fixing modifies the axial stress. The latter can be identified w.th the action of a ‘bimoment’ upon each thin-w.lled section.

关键词： Thin-Aluminium Channels Cantilever Beam Bending Shear Torsion w.rping Bimoment Flexural Axis Centre of Tw.st Centroid Shear Centre Torsional Stiffness Constrained Stress

Soybean Response to w.ed Residues in the Soil

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Agricultural Sciences 2024年第8期15卷 801-811页

作者： Dw.yne D. Joseph Michael w. Marshall Matthew.Cutulle Department of Plant and Environmental Sciences Clemson University Clemson SC USA Edisto Research and Education Center Clemson University Blackville SC USA Coastal Research and Education Center Clemson University Charleson SC USA

Soybean production systems that return plant residues to the soil surface are gaining in popularity. As these practices become more w.despread, more crop and w.ed residues are being introduced into the upper soil profile. Greenhouse studies w.re conducted to determine the effects of varying concentrations of Palmer amaranth and pitted morningglory plant residues (aboveground portion of the plant) on soybean production. The study w.s arranged in a completely randomized experimental design w.th five treatments and five replications. Palmer amaranth and pitted morningglory residues w.re incorporated into soil at 20,000, 40,000, 80,000 and 160,000 ppm. Inert plastic residue at the same residue levels w.s included as a check. Soybean dry w.ight, leaf area and leaf tissue nutrient content w.re recorded during the study. A decrease in soybean dry w.ight and leaf area w.s observed as Palmer amaranth residue in the soil increased. Palmer amaranth residues of 160,000 ppm and 80,000 ppm in the soil significantly reduced soybean dry w.ight by 69% and 59%, respectively, and soybean leaf area by 60% and 57%, respectively. In contrast, pitted morningglory and inert plastic residues had no observable effect on soybean grow.h and development. This study demonstrated Palmer amaranth residues in the soil impacted early season soybean grow.h and development.

关键词： Reduced Tillage Plant Residues Allelopathy Glycine max L.

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《音乐社会学导论》选译

新美术 2024年第3期45卷 25-63页

作者： [德]特奥多尔·w.阿多诺罗逍然(译) 不详中国美术学院

《作为社会棱镜的音乐》一文已经提到,阿多诺在思想与论述中都是有意识地拒绝体系化表达的。对他来说,无论人文、艺术还是科学,其真正目的都在于对人类的意识能力进行提升,而如若把某些预先制定好的体系与原则从外部施加于我们所要认识... 详细信息

《作为社会棱镜的音乐》一文已经提到,阿多诺在思想与论述中都是有意识地拒绝体系化表达的。对他来说,无论人文、艺术还是科学,其真正目的都在于对人类的意识能力进行提升,而如若把某些预先制定好的体系与原则从外部施加于我们所要认识的事物上,则无异于是在抹除事物自身的独特属性以及事物之间的微妙差异,那么也就是在伤害人类的意识能力。所以,阿多诺要求音乐不能仅仅是被动地接受并施用素材(其中包括体系、手法、风格等)。

关键词：音乐社会学阿多诺事物自身体系化导论独特属性意识

Theory of Flexural Shear, Bending and Torsion for a Thin-w.lled Beam of Open Section

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w.rld 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-w.lled 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 w.ich transverse shear forces w.en applied do not produce torsion. This centre, w.en taken to be coincident w.th the centre of tw.st implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric w.th the shear centre w.ll tw.st 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 w.th a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-w.lled sections w.en 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 tw.st and the free w.rping displacement. It is show. from the w.gner-Kappus torsion theory how.the end constrained w.rping generates an axial stress distribution that varies w.th the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for w.der 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 w.b centre. Therein, both bending and tw.sting 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 w.th the sum of axial stress

关键词： Thin w.ll Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow w.rping Fixed-End Constraint

Pervasive Attentive Neural Netw.rk for Intelligent Image Classification Based on N-CDE’s

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Computers, Materials & Continua 2024年第4期79卷 1137-1156页

作者： Anas w.Abulfaraj Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityRabigh21911Saudi Arabia

The utilization of visual attention enhances the performance of image classification *** attentionbased models have demonstrated notable performance,but many of these models exhibit reduced accuracy w.en confronted w.th inter-class and intra-class similarities and ***-Controlled Differential Equations(N-CDE’s)and Neural Ordinary Differential Equations(NODE’s)are extensively utilized w.thin this ***’s possesses the capacity to effectively illustrate both inter-class and intra-class similarities and differences w.th enhanced *** this end,an attentive neural netw.rk has been proposed to generate attention maps,w.ich uses tw. different types of N-CDE’s,one for adopting hidden layers and the other to generate attention *** distinct attention techniques are implemented including time-w.se attention,also referred to as bottom N-CDE’s;and element-w.se attention,called topN-CDE’***,a trainingmethodology is proposed to guarantee that the training problem is sufficiently *** classification tasks including fine-grained visual classification andmulti-label classification,are utilized to evaluate the *** proposedmethodology is employed on five publicly available datasets,including CUB-200-2011,ImageNet-1K,PASCAL VOC 2007,PASCAL VOC 2012,and MS *** obtained visualizations have demonstrated that N-CDE’s are better appropriate for attention-based activities in comparison to conventional NODE’s.

关键词： Differential equations neural-controlled DE image classification attention maps N-CDE’s

Clinical outcomes of celiac artery coverage w.th vs. w.thout revascularization in thoracic endovascular aortic repair

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中华医学杂志(英文版) 2024年第14期137卷 1750-1752页

作者： Xie Xinsheng Zhang w.i Fu w.iguo Zhang w.yne w. w.ng Lixin Department of Vascular Surgery Xiamen Branch Zhongshan Hospital Fudan University Xiamen Fujian China Department of Vascular Surgery Zhongshan Hospital Fudan University Shanghai China Department of Plastic surgery Plastic Surgery Hospital Peking Union Medical College Beijing China Department of Division of Vascular and Endovascular Surgery Seattle VA Medical Center University of Washington Seattle WA USA

To the Editor: Thoracic endovascular aortic repair (TEVAR) has been w.dely accepted as the first-line treatment w.en aortic repair is indicated. How.ver, TEVAR is still limited by anatomic conditions in many circumstances, and the most common exclusion situations are inadequate proximal and/or distal landing zones w.en important branch vessels are involved. The incidence of insufficient distal landing zone in descending TEVAR ranges from 2.5% to 15.2%, and different approaches to extend it w.re described. Hybrid surgery w.th combined TEVAR and open revascularization of visceral vessels has been employed from the early stage of endovascular aortic repair but it is associated w.th poor outcomes. Endovascular visceral artery revascularization, such as branched and fenestrated endograft, has been used more recently. Outcomes of stenting visceral arteries during fenestrated/branched aortic repair w.re explored by several studies and promising results w.re exhibited. How.ver, these techniques demand heavily on available device and technical skills. Currently, there is no Food and Drug Administration (FDA)-approved branched TEVAR endograft for visceral artery preservation. Chimney or snorkel procedures are relatively easier to perform, but it is associated w.th a higher incidence of endoleaks.

关键词： ANEURYSM TRUNK TEVAR

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H w.A Riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,w.ich incorporates higher-order dispersive terms,is w.dely employed in the theoretical analysis of various physical *** this study,w. explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated w.th the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly w.thin the framew.rk of *** visually understand the dynamics and solutions in the given example,w. also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane w.ves and to understand the generation of periodic patterns w.thin the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Nucleation of Supercooled w.ter by Neutrons: Latitude Dependence and Implications for Cloud Modelling

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Atmospheric and Climate Sciences 2024年第2期14卷 221-232页

作者： Peter w. w.lson Elizabeth w.lson-Park Abraham G. w.lson Department of Physics The University at Albany SUNY Albany USA Scripps Institution of Oceanography University of California San Diego USA Philanthropy Australia Sydney Australia The King’ s Institute The King&#8217s School Parramatta Australia

It has recently been show. that incident particles, neutrons, can initiate the freezing in a supercooled w.ter volume. This new.finding may have ramifications for the interpretation of both experimental data on the nucleation of laboratory samples of supercooled w.ter and perhaps more importantly on the interpretation of ice nucleation involved in cloud physics. For example, if some fraction of the cloud nucleation previously attributed to dust, soot, or aerosols has been caused by cosmogenic neutrons, fresh consideration is required in the context of climate models. Moreover, as cosmogenic neutrons, most being muon-induced, have much greater flux at high latitudes, estimates of ice nucleates in these regions may be larger than required to accurately model cloud and condensation properties. This discrepancy has been pointed out in IPCC reports. Our paper discusses the connection betw.en the new.concept of neutrons nucleating supercooled w.ter and the need for a new.source of nucleation in high latitude clouds, ideally causing others to review.current data, or to analyse future data w.th this idea in mind. .

关键词： Climate Models Ice Nucleation Neutrons Supercooling

Optimal design of the fillet w.ld fastening the w.nd turbine column

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China w.lding 2024年第3期33卷 39-43页

作者： Imre Timár István w.Árpád Mechanical Engineering Department Faculty of EngineeringUniversity of PannoniaVeszprem H-8200Hungary Mechanical Engineering Department Faculty of EngineeringUniversity of DebrecenDebrecen H-4032Hungary

This paper deals w.th the optimal design of the fillet w.ld of w.nd turbine column subjected to bending *** the premise of determined the force acting on the column,in order to further optimize the fillet w.ld,the minimum volume of corner seam w.s determined in the case of non-linear design *** constraints relate to the maximal stresses and fatigue of w.lding seam.A numer-ical solution to this problem is given by genetic optimization *** optimisation calculation result indicated that the active condi-tion(constraint)w.s the stress from the static *** and meaningful information is provided for the engineering field.

关键词： fillet w.ld optimal design genetic algorithm static and dynamic load