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Numerical and experimental investigation to design a novel morphing airfoil for performance optimization

Propulsion and Power Research 2023年第1期12卷 83-103页

作者： Kiumars Khani Aminjan Maryam Ghodrat Milad Heidari Pooyan Rahmanivahid Shayan Naghdi Khanachah Mira Chitt juan pablo escobedo-diaz Faculty of Aerospace Malek Ashtar University of TechnologyTehran 1774-15875Iran School of Engineering and Information Technology University of New South Wales CanberraCanberraACT 2610Australia Mechanical Engineering Department Global College of Engineering and Technology(GCET)P.O.Box 2546 CPO Ruwi 112MuscatSultanate of Oman School of Industrial Engineering Iran University of Science and TechnologyTehran 16846-13114Iran

Optimizing flying objects’wing performance has attracted a significant attention in the last few *** this article,some of the main mechanisms for changing the geometry of the wing were investigated and a new mechanism is proposed to improve the aerodynamic performance of the airplane *** designs have been simulated and analyzed from both aerodynamic and control points of *** aerodynamic simulations using CFD methods,two airfoils of NACA series 6 with specifications 65-212 and 65-2012 were *** results indicated that both airfoils used have a better performance compared to others in a certain range of the angle of ***,a new mechanism is proposed to change the wing geometry to optimize its *** the proposed mechanism,the structures of airfoils and wings consist of two fixed and moving parts,which can change their geometry with the help of a control *** fixed part has a grooved track,and as the moving part moves in the direction of the grooves,the curvature of the upper and lower parts of the wing *** design control circuit includes an angle sensor,a micro controller,and a *** CFD results are entered into the micro controller as *** any moment,the micro controller receives the angle data from the angle sensor and by comparing them with the CFD data,and issuing a command to the servomotor,it situates the wing curvature in the optimal state at all *** built mechanism was tested at an attack angle of 0°and 25°.The results showed that the different parts of the mechanism work with very high precision and put the geometric shape of the wing in an optimal state in a completely intelligent *** should be noted that the average error in test for t/c and Xt/c was 15.3% and 9%,respectively.

关键词： Morphing airfoil Lift force Optimization Computational fluid dynamics Micro controller Angle sensor

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Ballistic impact response of flexible and rigid UHMWPE textile composites:Experiments and simulations

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Defence Technology（防务技术） 2023年第4期22卷 37-53页

作者： Hongxu Wang Dakshitha Weerasinghe Paul J.Hazell Damith Mohotti Evgeny V.Morozov juan P.escobedo-diaz School of Engineering and Information Technology The University of New South WalesCanberraACT2600Australia

This study elaborates on the effects of matrix rigidity on the high-velocity impact behaviour of UHMWPE textile composites using experimental and numerical *** composite samples were manufactured of a plain-weave fabric(comprising Spectra?1000 fibres)and four different matrix ***-velocity impact tests were conducted by launching a spherical steel projectile to strike on the prepared samples via a gas *** experimental results showed that the textile composites gradually changed from a membrane stretching mode to a plate bending mode as the matrix rigidity and thickness *** composites deformed in the membrane stretching mode had higher impact resistance and energy absorption capacity,and it was found that the average energy absorption per ply was much higher in this mode,although the number of broken yarns was smaller in the perforated ***,the flexible matrix composites always had higher perforation resistance but larger deformation than the rigid matrix counterparts in the tested thickness and velocity range.A novel numerical modelling approach with enhanced computational efficiency was proposed to simulate textile composites in mesoscale *** simulation results revealed that stress and strain development in the more rigid matrix composite was localised in the vicinity of the impact location,leading to larger local deformation and inferior perforation resistance.

关键词： Impact behaviour Textile composite UHMWPE fibre Energy absorption Finite element analysis

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Some Smoothness Results for Classical Problems in Optimal Design and Applications

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 703-714页

作者： juan CASADO-diaz Dpto.de Ecuaciones Diferenciales y Analisis Numerico University of Seville41012 SevillaSpain

The author considers two classical problems in optimal design consisting in maximizing or minimizing the energy corresponding to the mixture of two isotropic materials or two-composite material. These results refer to... 详细信息

关键词： Optimal design Two-phase material Non-existence Relaxation

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Diagnosis of voiding dysfunction by pressure-flow study in women

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World Journal of Clinical Urology 2016年第1期5卷 29-36页

作者： juan pablo Valdevenito Annerleim Walton-diaz Urodynamics Unit Department of Urology Hospital Clinico Universidad de Chile

Pressure-flow study(PFS) of micturition is the best method to quantitatively analyse voiding function. It allows us to distinguish voiding lower urinary tract symptoms and low urine flow rate caused by bladder outlet obstruction(BOO) from those caused by detrusor underactivity(DU). Voiding dynamics are significantly different in men and women and the established criteria for urodynamic diagnosis in men do not apply to women. Basic principles of voiding mechanics and voiding patterns in asymptomatic women are analyzed. Although attempts have been made to establish a consensus for diagnosis of BOO in women with pressure-flow cutoff, video-urodynamics criteria and nomograms, currently there is no consensus. There is no standard urodynamic test to diagnose and quantify DU in women for which further investigations are needed. Modified projected isovolumetric pressure(to assess detrusor contraction strength) and pressure-flow cutoff criteria have been used. The diagnosis of voiding dysfunction in women is challenging, requiring PFS with very good quality control and often involves integrating clinical and radiographic data to make the final assessment.

关键词： Bladder outlet obstruction Pressure-flow studies Urodynamics Women Detrusor underactivity

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Female control of sperm ejection and retention in the cornsilk fly Euxesta eluta(Diptera:Ulididae)

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Insect Science 2023年第4期30卷 1183-1190页

作者： Solana Abraham Andrea Moyano Viviana diaz MGabriela Murua juan Rull Laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales(LIEMEN) PROIMI-BiotecnologiaCONICETTucumanArgentina Instituto de Tecnologia Agroindustrial del Noroeste Argentino(ITANOA) Estacion Experimental Agroindustrial Obispo Colombres(EEAOC)—CONICETTucumanArgentina

Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular ***,distinguishing between male sperm com-petition and active female sperm choice is difficult for species with internal ***,species that store and use sperm of different males in different storing struc-tures and species where females are able to expel all or part of the ejaculates after cop-ulation may be able to bias *** report a series of experiments aimed at pro-viding evidence of female sperm choice in Euxesta eluta(Hendel),a species of ulidiid fly that expels and consumes ejaculates after *** found no evidence of greater reproductive success for females mated singly,multiply with the same male,or mated multiply with different *** *** possesses two spherical spermathecae and a bursa copulatrix for sperm storage,with a ventral *** was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after *** mated with protein-fed males had greater reproductive success than similar females mated to protein-deprived ***-fed females prevented to consume the ejaculate,retained more sperm when mated to protein-fed males than when mated to protein-deprived *** results suggest that female *** can exert control of sperm retention of higher quality males through ejaculate ejection.

关键词： bursa copulatrix cornsilk fly cryptic female choice ejaculate consumption sperm choice spermathecae

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Assessing a novel modelling approach with high resolution UAV imagery for monitoring health status in priority riparian forests

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Forest Ecosystems 2021年第4期8卷 810-830页

作者： juan Guerra-Hernandez Ramon A.diaz-Varela juan Gabriel Avarez-Gonzalez Patricia Maria Rodriguez-Gonzalez edata Centro de iniciativas empresariaisFundacion CEL.O Palomar s/n27004 LugoSpain Forest Research Centre School of AgricultureUniversity of LisbonInstituto Superior de Agronomia(ISA)Tapada da Ajuda1349-017 LisbonPortugal Biodiversity and Applied Botany Unit(GI BIOAPLIC 1809) Department of BotanyEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus Universitario27002 LugoSpain Sustainable Forest Management Unit(UXFS) Department of Agroforestry EngineeringEscuela Politecnica SuperiorR/Benigno LedoUniversity of Santiago de CompostelaCampus UniversitarioE-27002 LugoSpain

Background:Black alder(Alnus glutinosa)forests are in severe decline across their area of distribution due to a disease caused by the soil-borne pathogenic Phytophthora alni species complex(class Oomycetes),“alder Phytopththora”.Mapping of the different types of damages caused by the disease is challenging in high density ecosystems in which spectral variability is high due to canopy *** obtained by unmanned aerial vehicles(UAVs)may be particularly useful for such tasks due to the high resolution,flexibility of acquisition and cost efficiency of this type of *** this study,*** decline was assessed by considering four categories of tree health status in the field:asymptomatic,dead and defoliation above and below a 50% threshold.A combination of multispectral Parrot Sequoia and UAV unmanned aerial vehicles-red green blue(RGB)data were analysed using classical random forest(RF)and a simple and robust three-step logistic modelling approaches to identify the most important forest health indicators while adhering to the principle of parsimony.A total of 34 remote sensing variables were considered,including a set of vegetation indices,texture features from the normalized difference vegetation index(NDVI)and a digital surface model(DSM),topographic and digital aerial photogrammetry-derived structural data from the DSM at crown ***:The four categories identified by the RF yielded an overall accuracy of 67%,while aggregation of the legend to three classes(asymptomatic,defoliated,dead)and to two classes(alive,dead)improved the overall accuracy to 72% and 91% *** the other hand,the confusion matrix,computed from the three logistic models by using the leave-out cross-validation method yielded overall accuracies of 75%,80% and 94% for four-,three-and two-level classifications,***:The study findings provide forest managers with an alternative robust classification method for the rapid,effective assessment of area

关键词： Alder RPAS Multi-spectral Defoliation Texture variables 3D point cloud Tree health monitoring

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Photosynthetic and Molecular Markers of CO_2-mediated Photosynthetic Downregulation in Nodulated Alfalfa

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Journal of Integrative Plant Biology 2013年第8期55卷 721-734页

作者： Alvaro Sanz-Sez Gorka Erice Iker Aranjuelo Ricardo Aroca juan Manuel Ruíz-Lozano Jone Aguirreolea juan Jos Irigoyen Manuel Sanchez-diaz Department of Plant Biology University of NavarraPamplonaE-31008Spain Department of Plant Biology University of BarcelonaBarcelonaE-8028Spain Department of Plant Biology University of Illinois at Urbana-Champaign61801USA Agrobiotechnology Institute Public University of NavarraMutilva BajaE-31192Spain Department of Soil Microbiology and Symbiotic Systems Zaidin Experimental Station(CSIC)GranadaE-18008.Spain

Elevated CO2 leads to a decrease in potential net photosynthesis in long-term experiments and thus to a reduction in potential growth. This process is known as photosynthetic downregulation. There is no agreement on the definition of which parameters are the most sensitive for detecting CO2 acclimation. In order to investigate the most sensitive photosynthetic and molecular markers of CO2 acclimation, the effects of elevated CO2, and associated elevated temperature were analyzed in alfalfa plants inoculated with different Sinorhizobium meliloti strains. Plants （Medicago sativa L. cv. Aragon） were grown in summer or autumn in temperature gradient greenhouses （TGG）. At the end of the experiment, all plants showed acclimation in both seasons, especially under elevated summer temperatures. This was probably due to the lower nitrogen （N） availability caused by decreased N2-fixation under higher temperatures. Photosynthesis measured at growth CO2 concentration, rubisco in vitro activity and maximum rate of carboxylation were the most sensitive parameters for detecting downregulation. Severe acclimation was also related with decreases in leaf nitrogen content associated with declines in rubisco content （large and small subunits） and activity that resulted in a drop in photosynthesis. Despite the sensitivity of rubisco content as a marker of acclimation, it was not coordinated with gene expression, possibly due to a lag between gene transcription and protein translation.

关键词： Carbon dioxide Medicago sativa (alfalfa) photosynthetic downregulation RbcL and RbcS Sinorhizobium meliloti.

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Promiscous female Euxesta eluta derive nutrients for ovarian development by expelling and consuming ejaculates

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Insect Science 2020年第3期27卷 545-557页

作者： Solana Abraham Gisela Castillo Viviana diaz Guido Van Nieuwenhove Gabriela Murua juan Rull Laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales(LIEMEN) PROIMI-BiotecnologiaCONICETTucumanArgentina Fundacion Miguel Ullo Instde EntomologiaDepto ZoologiaMiguel Lillo 251San Miguel de TucumanTucumanArgentina Facultad de Ciencias Naturales e I.M.L Universidad Nacional de TucumanSan Miguel de TucumanTucumanArgentina Estacion Experimental Agroindustrial Obispo Colombres(EEAOC)_ITANOA CONICET TucumanArgentina

Seminal gifts range from important material donations to items that provide little direct benefit to ***,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after *** evolution and function of this peculiar behavior are currently *** performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior *** revealed that protein deprived *** females derive nutrients for ovarian development through consumption of ejaculates of protein fed *** seminal products affecting survival appear to be transferred in the consumed ***,ovarian development,in contrast to testes growth,occurs in detriment of *** preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single *** finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.

关键词： anautogeny polyandry postcopulatory female control seminal gifts sperm storage

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Rectal cancer treatment: improving the picture

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World Journal of Gastroenterology 2007年第44期13卷 5805-5812页

作者： juan A diaz-Gonzalez Leire Arbea Javier Aristu Department of Oncology Clinica Universitaria Universtity of Navarra Pamplona 31080 Spain

Multidisciplinary approach for rectal cancer treatment is currently well defined. Nevertheless, new and promising advances are enriching the portrait. Since the US NIH Consensus in the early 90's some new characters have been added. A bird's-eye view along the last decade shows the main milestones in the development of rectal cancer treatment protocols. New drugs, in combination with radiotherapy are being tested to increase response and tumor control outcomes. However, therapeutic intensity is often associated with toxicity. Thus, innovative strategies are needed to create a better-balanced therapeutic ratio. Molecular targeted therapies and improved technology for delivering radiotherapy respond to the need for accuracy and precision in rectal cancer treatment.

关键词： Rectal cancer Chemoradiotherapy Intensitymodulated radiation therapy Molecular targeted therapy

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Mantle derived crystal-poor rhyolitic ignimbrites:Eruptive mechanism from geochemical and geochronological data of the Piedra Parada caldera,Southern Argentina

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Geoscience Frontiers 2018年第5期9卷 1529-1553页

作者： Eugenio Aragon Antonio Castro juan diaz-Alvarado Lucio Pinotti Fernando D'eramo Manuel Demartis Jorge Coniglio Irene Hernando Carmen Rodriguez Centro de Investigaciones Geológicas(UNLP-CONICET) 1 N^o 644(1900)La PlataBuenos AiresArgentina Departamento de Geología Universidad de Huelva21071 HuelvaSpain Departamento de Geología Universidad de AtacamaCopayapu 485CopiapóChile Departamento de Geología Universidad Nacional de Río Cuarto(UNRC-CONICET)Ruta 36 km 601Río CuartoCórdobaArgentina

Trace elements, isotopic modeling and U-Th-Pb SHRIMP zircon age constraints are used to reconstruct the eruption history and magmatic processes of the Piedra Parada Caldera. In the early Eocene, the crystal-poor Barda Colorada ignimbrite(BCI), having >>15% micro-porphyritic crystals with respect to magmatic components, erupted a volume estimated in more than 300 km^3. The Piedra Parada caldera is located in the Patagonian Andes foreland, at the southern end of the calderas field of the Pilcaniyeu Volcanic Belt(PVB). This belt is related to an extensional tectonic setting as a result of the collision of the Farallon-Aluk ridge with South America, which enabled the development of a transform ocean/continental plate margin followed by the detachment of the Aluk plate and the opening of a slab window. The BCI extra-caldera Plateau is a >100 m thick deposit, having a lower unit with high silica(Si O_2> 76 wt.%),potassium poor rhyolitic composition(trondhjemitic like magma), and an upper unit with normal to high potassium rhyolitic composition(granitic like magma). A trace elements modeling of the BCI units shows that the BCI lower and upper units did not evolve from fractionation or immiscibility in the shallow magma reservoir. The BCI also have a primitive isotopic signature(initial87 Sr/86 Sr =0.7031-0.7049 and ε_(Nd)= +3.4 to +3.65). Thus, tectonic, compositional and isotopic constraints suggest the fast ascent of high silica magmas to a shallow reservoir, and point to an upper mantle origin for these rhyolitic magmas in a transitional(Orogenic-Anorogenic) tectono-magmatic setting. U-Th-Pb SHRIMP zircon crystallization ages of the Syn-caldera stage BCI units(56 -51.5 Ma) show a protracted life of 5 Ma for this caldera reservoir. The age of 52.9 ± 0.3 Ma is considered the best fit for the possible maximum age for the caldera collapse. The Late-caldera magmatism has trachyandesitic and rhyolitic *** trace element modeling suggests that these rhyolites evolv

关键词： Mantle derived rhyolite Crystal-poor ignimbrite Bimodal volcanism Slab window volcanism K poor-rhyolite

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