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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang Yu Ao Shaofan Li Grace X.Gu department of Mechanical Engineering University of CaliforniaBerkeley 94720USA department of Engineering Peking UniversityBeijing 100871China department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

Development of design charts to predict the dynamic response of pile supported machine foundations

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 663-679页

作者： Deepthi SUDHI Sanjit BISWAS Bappaditya MANNA department of Civil Engineering National Institute TechnologyWarangal 506004India department of Civil Engineering Indian Institute of TechnologyDelhi 110016India

This paper proposes design charts for estimating imperative input parameters for continuum approach analysis of the nonlinear dynamic response of *** and analytical studies using continuum approach have been conducted on single and 2×2 grouped piles under coupled and vertical modes of vibration,for different dynamic forces and pile *** these design charts are derived from model piles,the charts have been validated for prototype pile foundations using scaling *** experimental responses of model piles are scaled up and these responses exhibit good agreement with analytical *** study also extends to estimation of the errors in computing frequency–amplitude responses with an increase in pile *** is found that,with an increase in pile length,the errors also *** effectiveness of the proposed design charts is also checked with data based on different field setups given in existing literature,and these charts are found to be ***,the developed design charts can be beneficial in estimating the input parameters for continuum approach analysis for determining the nonlinear responses of pile supported machine foundations.

关键词： pile foundation vertical vibration coupled vibration continuum approach soil-pile separation boundary zone parameters

The secondary injury cascade after spinal cord injury: an analysis of local cytokine/chemokine regulation

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Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： Daniel J.Hellenbrand Charles M.Quinn Zachariah J.Piper Ryan T.Elder Raveena R.Mishra Taylor L.Marti Phoebe M.Omuro Rylie M.Roddick Jae Sung Lee William L.Murphy Amgad S.Hanna department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public Health department of Biomedical Engineering University of Wisconsin-Madison department of Orthopedics and Rehabilitation University of Wisconsin-Madison department of Materials Science and Engineering University of Wisconsin-Madison Forward BIO Institute University of Wisconsin-Madison

After spinal cord injury, there is an extensive infiltration of immune cells, which exacerbates the injury and leads to further neural degeneration. Therefore, a major aim of current research involves targeting the immune response as a treatment for spinal cord injury. Although much research has been performed analyzing the complex inflammatory process following spinal cord injury, there remain major discrepancies within previous literature regarding the timeline of local cytokine regulation. The objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury, identify sexual dimorphisms in terms of cytokine levels, and determine local cytokines that significantly change based on the severity of spinal cord injury. Rats were inflicted with either a mild contusion, moderate contusion, severe contusion, or complete transection, 7 mm of spinal cord centered on the injury was harvested at varying times post-injury, and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex assay. Results demonstrated pro-inflammatory cytokines including tumor necrosis factor α, interleukin-1β, and interleukin-6 were all upregulated after spinal cord injury, but returned to uninjured levels within approximately 24 hours post-injury, while chemokines including monocyte chemoattractant protein-1 remained upregulated for days post-injury. In contrast, several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days post-injury. After spinal cord injury, tissue inhibitor of metalloproteinase-1, which specifically affects astrocytes involved in glial scar development, increased more than all other cytokines tested, reaching 26.9-fold higher than uninjured rats. After a mild injury, 11 cytokines demonstrated sexual dimorphisms; however, after a severe contusion only leptin levels were different between female and male rats. In conclus

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

Effects of Exogenous Indole Butyric Acid and Callus Formation on the Anti-oxidant Activity, Total Phenolic, and Anthocyanin Constituents of Mulberry Cuttings

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Journal of Integrative Plant Biology 2006年第7期48卷 832-837页

作者： Aysel Sivaci Munevver Sokmen department of Biology Sinop Science and Literature Faculty Ondokuz Mayis University Sinop Turkey department of Chemistry Faculty of Science and Literature Cumhuriyet University Sivas Turkey

In order to evaluate the effects of exogenous indole butyric acid （IBA） and callus formation on the antioxidant activity, total phenolics, and anthocyanin constituents of Morus nigra L. and M. alba L. cuttings, we investigated the variations before and after the treatment. The results indicate that anti-oxidant ability, total phenolic, and anthocyanin constituents of the callus stems of both Morus species were higher than those of non-callus forming species. There were also increases observed in anti-oxidant ability, total phenolic, and anthocyanin constituents of calli treated with IBA （1 000-3 000 mg/L）.

关键词： anthocyanin anti-oxidant activity callus cutting indole butyric acid mulberry phenolics.

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.M.FEIZABAD M.H.YAS department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** Hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

Raman spectroscopy monitors adverse bone sequelae of cancer radiotherapy

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Chinese Chemical Letters 2015年第4期26卷 401-406页

作者： Bo Gong Michael D.Morris department of Chemistry College of LiteratureScience and the ArtsUniversity of Michigan

Raman spectroscopy provides information on bone chemical composition and structure via widely used metrics including mineral to matrix ratio, mineral crystallinity and carbonate content, collagen cross- linking ratio and depolarization ratios. These metrics are correlated with bone material properties, such as hardness, plasticity and Young＇s modulus. We review application of Raman spectroscopy to two important irradiated animal models： the mouse tibia, a model for damage to cortical bone sites including the rib （breast cancer） and to healthy tissue adjacent to extremity sarcomas, and the rat mandible, a model for radiation damage in head and neck cancer radiotherapy. Longitudinal studies of irradiated mouse tibia demonstrate that radiation-induced matrix abnormalities can persist even 26 weeks post- radiation. Polarized Raman spectroscopy shows formation of more ordered orientation of both mineral and collagen. At 8 weeks post-radiation, irradiated rat hemimandible exhibits transient hyperminer- alization, increased collagen cross-linking and decreased depolarization ratios of mineral and collagen. A standard radioprotectant, amifostine, mitigates rat mandible radiation damage, with none remaining detectable 18 weeks post-radiation. Already a powerful tool to monitor radiation damage, Raman spectroscopy may be important in development of new radiotherapy protocols and radioprotective agents. Further in vfvo studies of radiation effects on the rodent models are underway, as are development of methodologies for eventual use in human subjects.

关键词： BoneRaman spectroscopyCancer radiotherapy

Increasing the Maximum Capacity Path in a Network and Its Application for Improving the Connection Between Two Routers

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Tsinghua Science and Technology 2024年第3期29卷 753-765页

作者： Adrian M.Deaconu Javad Tayyebi department of Mathematics and Computer Science Transilvania University of BrasovBrasov 500036Romania department of Industrial Engineering Birjand University of TechnologyBirjand 000097Iran

Abstract:This paper addresses the problem of improving the optimal value of the Maximum Capacity Path(MCP)through expansion in a flexible network,and minimizing the involved *** only condition applied to the cost functions is to be non-decreasing *** is a non-restrictive condition,reflecting the reality in practice,and is considered for the first time in the ***,the total cost of expansion is a combination of max-type cost(e.g.,for supervision)and sum-type cost(*** building infrastructures,price of materials,price of labor,etc.).For this purpose,two types of strategies are combined:(l)increasing the capacity of the existing arcs,and(l)adding potential new *** different problems are introduced and *** the problems have immediate applications in Internet routing *** first one is to extend the network,so that the capacity of an McP in the modified network becomes equal to a prescribed value,therefore the cost of modifications is minimized.A strongly polynomial-time algorithm is deduced to solve this *** second problem is a network expansion under a budget constraint,so that the capacity of an McP is maximized.A weakly polynomial-time algorithm is presented to deal with *** the special case when all the costs are linear,a Meggido's parametric search technique is used to develop an algorithm for solving the problem in strongly polynomial *** new approach has a time complexity of O(n^(4)),which is better than the time complexity of O(n4 log(n)of the previously known method from literature.

关键词： Maximum Capacity Path(MCP) network expansion Internet routing polynomial-time algorithms

Chaotic Aquila Optimization Algorithm for Solving Phase Equilibrium Problems and Parameter Estimation of Semi-empirical Models

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Journal of Bionic Engineering 2024年第1期21卷 486-526页

作者： Oguz Emrah Turgut Mert Sinan Turgut Erhan Kırtepe department of Industrial Engineering Faculty of Engineering and ArchitectureIzmir Bakircay UniversityMenemenizmirTurkey department of Mechanical Engineering Faculty of EngineeringEge UniversityBornovaizmirTurkey department of Motor Vehicles and Transportation Technologies Sirnak UniversitySirnakTurkey

This research study aims to enhance the optimization performance of a newly emerged Aquila Optimization algorithm by incorporating chaotic sequences rather than using uniformly generated Gaussian random *** work employs 25 different chaotic maps under the framework of Aquila *** considers the ten best chaotic variants for performance evaluation on multidimensional test functions composed of unimodal and multimodal problems,which have yet to be studied in past literature *** was found that Ikeda chaotic map enhanced Aquila Optimization algorithm yields the best predictions and becomes the leading method in most of the *** test the effectivity of this chaotic variant on real-world optimization problems,it is employed on two constrained engineering design problems,and its effectiveness has been ***,phase equilibrium and semi-empirical parameter estimation problems have been solved by the proposed method,and respective solutions have been compared with those obtained from state-of-art *** is observed that CH01 can successfully cope with the restrictive nonlinearities and nonconvexities of parameter estimation and phase equilibrium problems,showing the capabilities of yielding minimum prediction error values of no more than 0.05 compared to the remaining algorithms utilized in the performance benchmarking process.

关键词： Aquila optimization algorithm Chaotic maps Parameter estimation Phase equilibrium Unconstrained optimization

Research progress in friction stir processing of magnesium alloys and their metal matrix surface composites: Evolution in the 21^(st )century

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Journal of Magnesium and Alloys 2024年第6期12卷 2091-2146页

作者： Roshan Vijay Marode Tamiru Alemu Lemma Nabihah Sallih Srinivasa Rao Pedapati Mokhtar Awang Adeel Hassan department of Mechanical Engineering Universiti Teknologi PETRONASBandarSeri IskandarPerak 32610Malaysia department of Mechanical Engineering College of EngineeringThe University of Texas Permian BasinMidland-OdessaUnited States Mechanical Engineering department Universiti Teknologi BruneiBrunei

Rising concerns about climate change drive the demand for lightweight ***(Mg)alloys are highly valued for their low weight,making them increasingly important in various *** focusing on enhancing the characteristics of Mg alloys and developing their Metal Matrix Composites(MMCs)have gained significant attention worldwide over the past decade,driven by the global shift towards lightweight *** Stir Processing(FSP)has emerged as a promising technique to enhance the properties of Mg alloys and produce ***,FSP adapted to refine grain size from the micro to the nano level and accelerated the development of MMCs due to its solid-state nature and the synergistic effects of microstructure refinement and reinforcement,improving strength,hardness,ductility,wear resistance,corrosion resistance,and fatigue ***,producing defect-free and sound FSPed Mg and Mg-MMCs requires addressing several variables and their interdependencies,which opens up a broad range of practical *** existing reviews on individual FSP of Mg,its alloys,and MMCs,an attempt has been made to analyze the latest research on these three aspects collectively to enhance the understanding,application,and effectiveness of FSP for Mg and its *** review article discusses the literature,classifies the importance of Mg alloys,provides a historical background,and explores developments and potential applications of FSPed Mg *** focuses on novel fabrication methods,reinforcement strategies,machine and tool design parameters,material characterization,and integration with other methods for enhanced *** influence of process parameters and the emergence of defects are examined,along with specific applications in mono and hybrid composites and their microstructure *** study identifies promising reinforcement materials and highlights research gaps in FSP for Mg alloys and MMCs *** conclude

关键词： Magnesium alloys Friction stir processing Metal matrix composites Lightweight Surface modification

Eigenfrequency analysis of bridges using a smartphone and a novel low-cost accelerometer prototype

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 202-215页

作者： Seyedmilad KOMARIZADEHASL Ye XIA Mahyad KOMARY Fidel LOZANO department of Civil and Environment Engineering Universitat Politècnica de CatalunyaBarcelona 08034Spain department of Bridge Engineering Tongji UniversityShanghai 200092China department of Civil Engineering Universidad de Castilla-La ManchaCiudad Real 13071Spain

Researchers are paying increasing attention to the development of low-cost and microcontroller-based accelerometers,in order to make structural health monitoring feasible for conventional bridges with limited monitoring *** with the low-cost sensor development,the use of the embedded accelerometers of smartphones for eigenfrequency analysis of bridges is becoming popular in the civil engineering *** paper,for the first time in the literature,studies these two promising technologies by comparing the noise density and eigenfrequency analysis of a self-developed,validated and calibrated low-cost Internet of things based accelerometer LARA(low cost adaptable reliable accelerometer)with those of a state of the art smartphone(iPhone XR).The eigenfrequency analysis of a footbridge in San Sebastian,Spain,showed that the embedded accelerometer of the iPhone XR can measure the natural frequencies of the under study bridge.

关键词： smartphone modal analysis eigenfrequency analysis low-cost accelerometers Arduino Raspberry Internet of things