33 research outputs found

    Solving a novel designed second order nonlinear Lane-Emden delay differential model using the heuristic techniques

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    The aim of the present study is to present a new model based on the nonlinear singular second order delay differential equation of Lane鈥揈mden type and numerically solved by using the heuristic technique. Four different examples are presented based on the designed model and numerically solved by using artificial neural networks optimized by the global search, local search methods and their hybrid combinations, respectively, named as genetic algorithm (GA), sequential quadratic programming (SQP) and GA-SQP. The numerical results of the designed model are compared for the proposed heuristic technique with the exact/explicit results that demonstrate the performance and correctness. Moreover, statistical investigations/assessments are presented for the accuracy and performance of the designed model implemented with heuristic methodology.This paper has been partially supported by Ministerio de Ciencia, Innovaci贸n y Universidades, Spain grant number PGC2018-0971-B-100 and Fundaci贸n S茅neca de la Regi贸n de Murcia, Spain grant number 20783/PI/18

    Shortgrass Steppe LTER VI: examining ecosystem persistence and responses to global change, 2010-2014 proposal

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    Includes bibliographical references.The SGS-LTER research site was established in 1980 by researchers at Colorado State University as part of a network of long-term research sites within the US LTER Network, supported by the National Science Foundation. Scientists within the Natural Resource Ecology Lab, Department of Forest and Rangeland Stewardship, Department of Soil and Crop Sciences, and Biology Department at CSU, California State Fullerton, USDA Agricultural Research Service, University of Northern Colorado, and the University of Wyoming, among others, have contributed to our understanding of the structure and functions of the shortgrass steppe and other diverse ecosystems across the network while maintaining a common mission and sharing expertise, data and infrastructure.The Shortgrass Steppe Long-term Ecological Research (SGS-LTER) program focuses on how grassland ecosystems function and persist or change in the face of global change. Our conceptual framework asserts that climate, physiography, grazing, fire and landuse, operating over different spatial and temporal scales, are the dominant determinants of the structure, function, and persistence of the SGS. Using the shortgrass steppe (SGS) ecosystem of the North American Great Plains as a model, we seek to (1) identify the ecological attributes of grasslands that historically have resulted in their persistence and (2) understand these attributes in ways that will allow us to identify area of vulnerability and better forecast the future of grasslands in the face of global change. Given its geographic extent and history, the SGS encapsulates many of the features of a system driven by social-ecological interactions and the vulnerabilities of semiarid grasslands to global change. Our overarching question is: How will structure and function of the SGS respond to expected changes in climate, management, and land-use, and what will be the consequences

    Dynamical Systems

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    Complex systems are pervasive in many areas of science integrated in our daily lives. Examples include financial markets, highway transportation networks, telecommunication networks, world and country economies, social networks, immunological systems, living organisms, computational systems and electrical and mechanical structures. Complex systems are often composed of a large number of interconnected and interacting entities, exhibiting much richer global scale dynamics than the properties and behavior of individual entities. Complex systems are studied in many areas of natural sciences, social sciences, engineering and mathematical sciences. This special issue therefore intends to contribute towards the dissemination of the multifaceted concepts in accepted use by the scientific community. We hope readers enjoy this pertinent selection of papers which represents relevant examples of the state of the art in present day research. [...

    Technology for large space systems: A bibliography with indexes (supplement 14)

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    This bibliography lists 645 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1985 and December 31, 1985. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

    Space station systems: A bibliography with indexes

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    This bibliography lists 967 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1987 and June 30, 1987. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems. The coverage includes documents that define major systems and subsystems, servicing and support requirements, procedures and operations, and missions for the current and future space station

    Space station systems: A bibliography with indexes (supplement 2)

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    This bibliography lists 904 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1985 and December 31, 1985. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems. The coverage includes documents that define major systems and subsystems, servicing and support requirements, procedures and operations, and missions for the current and future space station

    Electronic Journal of Qualitative Theory of Differential Equations 2022

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