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Investigation of Total Absorption of Radio Waves in High Latitude Ionosphere

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Plasma Science and Technology 2014年第9期16卷 833-836页

作者：史建魁王铮陶伟 g.A.ZHeReBTSOV e.B.ROMANOVA K.g.RATOVSKY State Key Laboratory of Space Weather NSSC/CAS Institute of Solar-Terrestrial Physics SB/RAS Irkutsk 664033 Russia

Using the digisonde data observed at ionospheric station Norilsk （Dip lat. 60~N） in 2006, a statistical study on the characteristics of the ionospheric plasma total absorption of radio waves （IPTAR） was performed. In the winter and some months of equinox, the IPTAR mainly occurred in the nighttime and the highest occurrence rate could be up to 90%. In the summer, the occurrence was relatively low and the differences between nighttime and daytime occurrence reduced. The total duration of IPTAR seemed longer around the winter than that around the summer. The occurrence of IPTAR events ascended as the Kp index increased. The frequent precipitation of energetic particles into the ionospheric plasma in the auroral belt may be the main cause of the IPTAR events.

关键词： ionosphere radio waves total absorption

Near-Net-Shaped Objects of Re123 Superconductors byInfiltration Processing

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Tsinghua Science and Technology 2003年第3期8卷 292-306页

作者： e.S.Reddy g.J.Schmitz ACCeSS Materials and Processes D-52056 AachenGermanyACCESS Materials and ProcessesD-52056 AachenGermany

The fabrication of near-net-shaped objects of Re123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211 or yttria phases by liquids containing barium cuprates and copper oxides followed by a controlled peritectic solidification. The process yields poly- and also single-crystalline superconducting objects with a shrinkage of less than half of one percent of the green bodies. The preservation of the initial structure of the green bodies results in fabrication of Re 123 in a wide variety of dimensions and complex shapes. The demonstrated products include bulk components like cylinders, single domain thick films on a variety of substrates, freestanding fabrics and open porous superconducting foams. This paper presents a comprehensive description of the infiltration processing technique and the resulting microstructures of the superconducting bodies. The advantages of this technique and practical applications of the processed superconducting structures are highlighted.

关键词： infiltration processing near-net shape shaping joining single domain crystal growth thick films foams applications

Preface： theory, methods, and applications of mesoscopic modeling

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Applied Mathematics and Mechanics(english edition) 2018年第1期39卷 1-2页

作者： Z. LI guohui HU g.e. KARNIADAKIS Division of Applied Mathematics Brown UniversityProvidenceRhode Island 02912U.S.A. Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China

With increasing attention to complex fluids and soft matter, we have witnessed a fast- growing research in mesoscopic modeling and simulation in the past decades. The development of mesoscopic methods offers many potential opportunities as well as challenges in modeling of complex materials for diverse applications. Despite significant progress in the past decade, mesoscopic methods are still under development. New formulation in the models, novel theo- retical interpretations, and innovative numerical algorithms often appear in literature. These mesoscopic methods have been already applied to a large number of problems, including poly- mer and colloidal suspensions, multiphase fluids, biological materials, and blood rheology. New applications of mesoscopic modeling in different areas are still emerging.

关键词： theory methods mesoscopic modeling

The Bamble Sector,South Norway:A review

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geoscience Frontiers 2014年第5期5卷 635-658页

作者： Timo g.Nijland Daniel e.Harlov Tom Andersen TNO P.O.Box 49.2600 AA Delft.The Netherlands geoForschungsZentrum Telegrafenberg14473 Potsdam.Germany Department of geology.University of Johannesburg P.O.Box 524.Auckland Park 2006.South Africa Department of geosciences.University of Oslo P.O.Box 1047.Blindern.0316 Oslo Norway

The Proterozoic Bamble Sector, South Norway, is one of the world＇s classic amphiboliteto granulite- facies transition zones. It is characterized by a well-developed isograd sequence, with isolated ＇granulite-facies islands＇ in the amphibolite-facies portion of the transition zone. The area is notable for the discovery of C02-dominated fluid inclusions in the granolite-facies rocks by Jacques Touter in the late 1960＇s, which triggered discussion of the role of carbonic fluids during granulite genesis. The aim of this review is to provide an overview of the current state of knowledge of the Bamble Sector, with an emphasis on the Arendal-Froland-Nelaug-Tvedestrand area and off shore islands （most prominantly Tromay and Hisoy） where the transition zone is best developed. After a brief overview of the history of geological research and mining in the area, aspects of sedimentary, metamorphic and magmatic petrology of the Bamble Sector are discussed, including the role of fluids. Issues relevant to current geotectonic models for SW Scandinavia, directly related to the Bamble Sector, are discussed at the end of the review.

关键词： Bamble SectorSouth NorwayCharnockiteAmphibolire- ro granulire-facies transitionCO2BrinesPrecambrian

Alarm cue induces an antipredator morphological defense in juvenile Nicaragua cichlids Hypsophrys nicaraguensis

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Current Zoology 2010年第1期56卷 36-42页

作者： Maria e.ABATe Andrew g. eNg Les KAUFMAN Department of Biology Boston University Department of Neurosurgery University of Pennsylvania

Olfactory cues that indicate predation risk elicit a number of defensive behaviors in fishes, but whether they are sufficient to also induce morphological defenses has received little attention. Cichlids are characterized by a high level of morphological plasticity during development, and the few species that have been tested do exhibit defensive behaviors when exposed to alarm cues released from the damaged skin of conspecifics. We utilized young juvenile Nicaragua cichlids Hypsophrys nicaraguensis to test if the perception of predation risk from alarm cue （conspecific skin extract） alone induces an increased relative body depth which is a defense against gape-limited predators. After two weeks of exposure, siblings that were exposed to conspecific alarm cue increased their relative body depth nearly double the amount of those exposed to distilled water （control） and zebrafish Danio rerio alarm cue. We repeated our measurements over the last two weeks （12 and 14） of cue exposure when the fish were late-stage juveniles to test if the rate of increase was sustained; there were no differences in final dimensions between the three treatments. Our results show that 1） the Nicaragua cichlid has an innate response to conspecific alarm cue which is not a generalized response to an injured fish, and 2） this innate recognition ultimately results in developing a deeper body at a stage of the life history where predation risk is high [Current Zoology 56 （1）： 36-42, 2010].

关键词： Alarm substance Inducible defense Phenotypic plasticity Cichlid Chemical cue Antipredator

electro-mechanical analysis of composite and sandwich multilayered structures by shell elements with node-dependent kinematics

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International Journal of Smart and Nano Materials 2018年第1期9卷 1-33,I0001页

作者： e.Carrera S.Valvano g.M.Kulikov Department of Mechanical and Aerospace engineering Politecnico di TorinoTurinItaly Laboratory of Intelligent Materials and Structures Tambov State Technical UniversityTambovRussia

In this work,a new class of finite elements for the analysis of composite and sandwich shells embedding piezoelectric skins and patches is *** main idea of models coupling is developed by presenting the concept of nodal dependent kinematics where the same finite element can present at each node a different approximation of the main unknowns by setting a nodewise through-the-thickness approximation *** a global/local approach scenario,the computational costs can be reduced drastically by assuming refined theories only in those zones/nodes of the structural domain where the resulting strain and stress states,and their electro-mechanical coupling present a complex *** numerical investigations are carried out to validate the accuracy and efficiency of the present shell *** accurate representation of mechanical stresses and electric displacements in localized zones is possible with reduction of the computational costs if an accurate distribution of the higherorder kinematic capabilities is *** the contrary,the accuracy of the solution in terms of mechanical displacements and electric potential values depends on the global approximation over the whole *** efficacy of the present node-dependent variable kinematic models,thus,depends on the characteristics of the problem under consideration as well as on the required analysis type.

关键词： Shell piezo composite structures global/local analysis Unified formulation nodedependent kinematics

Monte Carlo generator photon jets used for luminosity at e^+e^- colliders

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Chinese Physics C 2010年第6期34卷 877-882页

作者： g.V.Fedotovich e.A.Kuraev A.L.Sibidanov Budker Institute of Nuclear Physics Novosibirsk State University Joint Institute of Nuclear Research

A Monte-Carlo generator Photon Jets （MCgPJ） to simulate Bhabha scattering as well as production of two charged muons and two photons events is discussed. The theoretical precision of the cross sections with radiative corrections （RC） is estimated to be smaller than 0.2%. The Next Leading Order （NLO） radiative corrections proportional to α are treated exactly, whereas the all logarithmically enhanced contributions, related to photon jets emitted in the collinear region, are taken into account in frame of the Structure Function approach. Numerous tests of the MCgPJ as well as a detailed comparison with other MC generators are presented.

关键词： luminosity e^+e^- hadrons detectors

Impact of minimally invasive surgery on the treatment of benign esophageal disorders

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World Journal of gastroenterology 2012年第46期18卷 6764-6770页

作者： Brian Bello Fernando A Herbella Marco e Allaix Marco g Patti Department of Surgery University of Chicago Pritzker School of Medicine

Thanks to the development of minimally invasive surgery, the last 20 years have witnessed a change in the treatment algorithm of benign esophageal disorders. Today a laparoscopic operation is the treatment of choice for esophageal achalasia and for most patients with gastroesophageal reflux disease. Because the pathogenesis of achalasia is unknown, treatment is palliative and aims to improve esophageal emptying by decreasing the functional obstruction at the level of the gastro-esophageal junction. The refinement of minimally invasive techniques accompanied by large, multiple randomized control trials with long-term outcome has allowed the laparoscopic Heller myotomy and partial fundoplication to become the treatment of choice for achalasia compared to endoscopic procedures, including endoscopic botulinum toxin injection and pneumatic dilatation. Patients with suspected gastroesophageal reflux need to undergo a thorough preoperative workup. After establishing diagnosis, treatment for gastroesophageal reflux should be individualized to patient characteristics and a decision about an operation made jointly between surgeon and patient. The indications for surgery have changed in the last twenty years. In the past, surgery was often considered for patients who did not respond well to acid reducing medications. Today, the best candidate for surgery is the patient who has excellent control of symptoms with proton pump inhibitors. The minimally invasive approach to antireflux surgery has allowed surgeons to control reflux in a safe manner, with excellent long term outcomes. Like achalasia and gastroesophageal reflux, the treatment of patients with paraesophageal hernias has also seen a major evolution. The laparoscopic approach has been shown to be safe, and durable, with good relief of symptoms over the long-term. The most significant controversy with laparoscopic paraesophageal hernia repair is the optimal crural repair. This manuscript reviews the evolution of these tec

关键词： gastroesophageal reflux disease esophageal achalasia Hiatal hernia Laparoscopic fundoplication Laparoscopic Heller myotomy

Multilayered plate elements with node-dependent kinematics for electro-mechanical problems

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International Journal of Smart and Nano Materials 2018年第4期9卷 279-317,I0004页

作者： e.Carrera S.Valvano g.M Kulikov Department of Mechanical and Aerospace engineering Politecnico di TorinoTurinItaly Department of Applied Mathematics and Mechanics Tambov State Technical UniversityTambovRussia

In the present work,a new class of finite elements(Fes)for the analysis of composite and sandwich plates embedding piezoelectric skins and patches is *** making use of node-by-node variable plate theory assumptions,the new finite element allows for the simultaneous analysis of different subregions of the problem domain with different kinematics and accuracy,in a global/local *** a consequence,the computational costs can be reduced drastically by assuming refined theories only in those zones/nodes of the structural domain where the resulting strain and stress states,and their electro-mechanical coupling present a complex *** primary advantage is that no ad-hoc techniques and mathematical artifices are required to mix the fields coming from two different and kinematically incompatible adjacent elements,because the plate structural theory varies within the finite element *** other words,the structural theory of the plate element is a property of the Fe node in this present approach,and the continuity between two adjacent elements is ensured by adopting the same kinematics at the interface *** finite element arrays of the generic plate element are formulated in terms of fundamental nuclei,which are invariants of the theory approximation order and the modeling technique(equivalent-Single-Layer,Layer-Wise).In this work,the attention is focused on the use of Legendre polynomial expansions to describe the through-the-thickness unknowns to develop advanced plate *** numerical investigations,such as composite and sandwich multilayered plates embedding piezoelectric skins and patches with various load,boundary conditions,and piezoelectric material polarizations,are carried out to validate and demonstrate the accuracy and efficiency of the present plate element,including comparison with various closed-form and Fe solutions from the literature.

关键词： Multilayered plate elements piezoelectric global/local analysis carrera unified formulation node-dependent kinematics