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Chaotic dynamics and coexistence in a three species interaction model

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International Journal of Biomathematics 2015年第2期8卷 135-159页

作者： eduardo Saez eduardo Stange Ivan Szanto eduardo Gonzalez-Olivares Manuel Falconi Departamento de Matematica Universidad Tecnica Federico Santa Maria Valparaiso Chile Instituto de Matemdticas Universidad de Valparaiso Valparaiso Chile Departamento de Matemdtica Universidad Tdcnica Federico Santa Maria Valparaiso Chile Departamento de Matemdticas Facultad de Ciencias Universidad Nacional Autonoma de Mdxico Ciudad de Mexico Mexico

This work deals with a three-dimensional system, which describes a food web model consisting of a prey, a specialist predator and a top predator which is generalist as it consumes the other two species. Using tools of dynamical systems we prove that the trajectories of system are bounded and that open subsets of parameters exist, such that the system in the first octant has at most two singularities. For an open subset of the parameters space, the system is shown to have an invariant compact set and this is a topologically transitive attractor set. Finally, we find another open set in the parameters space, such that the system has two limit cycles each contained in different invariant planes. The work is completed with a numeric simulation showing the attractor is a strange attractor.

关键词： Food chain functional response bifurcation behavior dynamic separatrix curve stability.

On Building Practical Biocomputers for Real-world Applications： Receptacles for Culturing Slime Mould Memristors and Component Standardisation

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Journal of Bionic Engineering 2017年第1期14卷 151-162页

作者： Edward Braund eduardo Reck Miranda Interdisciplinary Centre for Computer Music Research (ICCMR) The House Plymouth University Drake Circus UK PL4 8AA

Our application of bionic engineering is novel： we are interested in developing hybrid hardware-wetware systems for music. This paper introduces receptacles for culturing Physarum polycephalum-based memristors that are highly accessible to the creative practitioner. The myxomycete Physarum polycephalum is an amorphous unicellular organism that has been found to exhibit memristive properties. Such a discovery has potential to allow us to move towards engineering electrical systems that encompass Physarum polycephalum components. To realise this potential, it is necessary to address some of the constraints associated with harnessing living biological entities in systems for real-time application. Within the paper, we present 3D printed receptacles designed to standardise both the production of components and memristive observations. Subsequent testing showed a significant decrease in growth time, increased lifespan, and superior similarity in component-to-component responses. The results indicate that our receptacle design may provide means of implementing hybrid electrical systems for music technology.

关键词： unconventional computing Physarum polycephalum computer music biological computing memristor

IMPROVING SOLVER PERFORMANCE THROUGH REDUNDANCY

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Journal of Systems Science and Systems Engineering 2016年第3期25卷 303-325页

作者： eduardo Lalla-Ruiz Stefan Voβ Department of Computer Engineering and Systems University of La Laguna Spain Institute of Information Systems (IWI) University of Hamburg Germany Eseuela de Ingenierla Industrial Pontificia Universidad Catolica de Valparaiso (PUCV) Chile

It is well known that hierarchies of mathematical programming formulatlons with different numbers of variables and constraints have a considerable impact regarding the quality of solutions obtained once these formulations are fed to a commercial solver. In addition, even if dimensions are kept the same, changes in formulations may largely influence solvability and quality of results. This becomes evident especially if redundant constraints are used. We propose a related framework for information collection based on these constraints. We exemplify by means of a well-known combinatorial optimization problem from the knapsack problem family, i.e., the multidimensional multiple-choice knapsack problem （MMKP）. This incorporates a relationship of the MMKP to some generalized set partitioning problems. Moreover, we investigate an application in maritime shipping and logistics by means of the dynamic berth allocation problem （DBAP）, where optimal solutions are reached from the root node within the solver.

关键词： Erraticism redundant constraints multidimensional multiple-choice knapsack problem,dynamic berth allocation problem

Recognition of trench basins in collisional orogens:Insights from the Yarlung Zangbo suture zone in southern Tibet

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Science China Earth Sciences 2020年第12期63卷 2017-2028页

作者： Xiumian Hu Wei An eduardo Garzanti Qun Liu Institute of Continental Geodynamics State Key Laboratory for Mineral Deposits ResearchSchool of Earth Sciences and EngineeringNanjing UniversityNanjing210023China School of Resources and Environmental Engineering Hefei University of TechnologyHefei230009China Department of Earth and Environmental Sciences Universitàdi Milano-BicoccaMilano20126Italy

Trench basin,as an important sedimentary repository in oceanic subduction zones,documents faithfully the evolution of paleodrainage and paleogeographic *** of the frequent intense deformation during and after deposition,the recognition of trench-basin strata in orogenic belts is quite *** trench-fill deposits have been identified from the Yarlung Zangbo suture in southern Tibet,which can be classified into two types based on major differences in formation timing and tectonic *** first type developed during subduction of the Neotethyan oceanic slab in the Cretaceous(e.g.,the Jiachala,Rongmawa,and Luogangcuo formations),and the second type developed during the initial stage of the India-Asia collision in the Palaeogene(e.g.,the Sangdanlin-Zheya formations).The former was originally deposited on the subducting oceanic crust and then accreted as tectonic slices into the subduction complex;the latter was deposited unconformably on the continental margin of the subducting Indian plate and then involved in the subduction complex during the continental *** lithologies of trench-basin fills include abyssal chert,siliceous shale,silty to sandy turbidites,debris flows deposits,and slump deposits without *** feeding these basins were chiefly from the uplifted terrane in the upper *** paper summarizes the geological features of trench basins developed in southern Tibet and proposes criteria for recognizing trench-basins in collisional orogens.

关键词： Trench basin.Provenance analysis Yarlung Zangbo suture zone Southern Tibet Cretaceous-Paleocene Himalayan orogen

Transmission line protection challenges influenced by inverter-based resources:a review

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Protection and Control of Modern Power Systems 2022年第1期7卷 406-422页

作者： Juan Carlos Quispe eduardo Orduña Institute of Electrical and Energy-CONICET Universidad Nacional de San JuanSan JuanArgentina Universidad Tecnológica del Perú LimaPeru

High penetration of renewable energy sources(RES)leads to new challenges for protection *** schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not ***,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the ***,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria *** work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through *** data on many representative publications related to this topic are obtained to show the current research lines and their proposed *** addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider ***,an analysis and discussion of the selected bibliography are presented.

关键词： Inverter-based resources Inverter control system Photovoltaic plant Transmission line protection Wind farm

Iterated Inverse Images of Plane Curve Singularities

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2319-2328页

作者： eduardo CASAS-ALVERO Joaquim ROE Departament d＇Algebra i Geometria Universitat de Barcelona Gran Via 585 08007 Barcelona Spain Departament de Matematiques Universitat Autonoma de Barcelona 08193 Bellaterra （Barcelona） Spain

We describe the evolution of certain multiplicities and intersection numbers of plane curve singularities under the iterated action of an analytic morphism.

关键词： Plane curve singularity analytic morphism dynamics of intersection

Hydrocarbon distribution along the Soapaga thrust(Eastern Cordillera, Colombia) based on new strategic geochemistry samples

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Acta Geochimica 2022年第3期41卷 335-350页

作者： eduardo A.Rossello Rolando Di Primio Departamento de Ciencias Geologicas Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaCONICET-IGEBAPabellon II1428 Buenos AiresArgentina Lundin Energy Norway LysakerNorway

The Colombian Eastern Cordillera constitutes a region with potential for finding hydrocarbon reserves that are still under-explored, despite the existence of oil and tar sand production. The intense tectonic deformation affects the petroleum systems and increases exploration challenges due to the different generation, maturation, and entrapment conditions that they produce. Diverse geochemical analysis conducted on strategic samples determines that these are likely generated by the same anoxic marine source rock type. Two source rock samples we investigated are characterized by very different biomarker signals as compared to the tar sands and oil samples. Both samples are dominated by hopanes as compared to tri-and tetracyclic terpanes, with very low(Tibasosa Formation) to no(Chipaque Formation) extended tricyclic terpanes. The Soapaga Thrust, along which the analyzed samples are located, has exercised first-rate regional structural control of the distribution of hydrocarbons in the studied area. The uplift of their Mesozoic hanging wall produces intense erosion with sediment transport towards the eastern footwall forming the present infill of the Arcabuco basin. The kitchen areas were connected with the shallower entrapment sectors where excellent reservoir levels such as the Picacho Formation before the Soapaga Thrust movement. The high degree of biodegradation observed in the Picacho Fm. tar sands support early charge before the Soapaga thrust movement, and severe biodegradation following the thrust movement when hydrocarbon supply from the kitchen was interrupted. This work aims to contribute to a better understanding of the geochemical characteristics of the petroleum systems due to the action of the Soapaga Thrust.

关键词： Hydrocarbon geochemistry Soapaga thrust Eastern Cordillera Colombia

H∞position transfer and regulation for floating offshore wind turbines

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Control Theory and Technology 2020年第3期18卷 231-245页

作者： eduardo Eribert ESCOBAR AQUINO Ryozo NAGAMUNE Department of Mechanical Engineering The University of British ColumbiaVancouverBC V671Z4Canada

This paper proposes H∞controller design for platform position transfer and regulation of floating offshore wind *** platform movability of floating wind turbines can be utilized in mitigating the wake effect in the wind farm,thereby maximizing the wind farm's total power capture and *** controller is designed so that aerodynamic force is adjusted to meet the three objectives simultaneously,that is,1)to generate the desired electrical power level,2)to achieve the desired platform position,and 3)to suppress the platform *** acquire sufficient aerodynamic force to move the heavy platform,the pitch-to-stall blade pitching strategy is taken instead of the commonly-used pitch-to-feather *** desired power level is attained by the standard constant-power strategy for the generator torque,while Hstate-feedback control of blade pitch and nacelle yaw angles is adopted for the position regulation and platform oscillation *** constants for the H∞controller design are adjusted to take the trade-off between the position regulation accuracy and the platform motion *** demonstrate the efficiency of the proposed controler,a virtual 5-MW semi-submersible wind turbine is *** results show that the designed H∞controller successfully accomplishes the platform position transfer and regulation as well as the platform oscillation reduction against wind and wave disturbances,and that it outperforms a previously-proposed linear quadratic controller with an integrator.

关键词： Offshore wind farm wind turbine position power regulation disturbance rejection H∞control

Sperm quality in mice acutely treated with parathion

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Asian Journal of Andrology 2000年第2期2卷 147-150页

作者： Cristian Sobarzo eduardo Bustos-Obregon Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.

Aim: To investigate the toxic effect of a single injection of the organophosphorous agropesticide, parathion, on sper-matogenesis in immature male mice. Methods: Seven-day old mice received a single injection of parathion intraperi-toneally at a dose of 1/3 LD_50. The epididymal sperm count, sperm morphology and chromatin thermal stability wereanalyzed 28 and 50 days after injection. Results: Sperm counts were decreased and teratozoospermia and thermal de-naturation of DNA increased after parathion injection. Sperm parameters were changed to a greater extent in younger an-imals, denoting a higher lability of spermatogenic process at its beginning. The damages could recover a long time afterparathion administration. Conclusion: Organophosphorous agropesticides are testicular toxicants, eliciting reversiblecytotoxic and cytogenetic alterations in germ cells.

关键词： epididymis spermatozoa organophosphorous compounds agropesticides spermatogenesis