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## Comportamento assintótico de sistemas não lineares discretos; Asymptotic behavior of non lineal discrete systems

Gabriel Filho, Luis Roberto Almeida
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
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Neste trabalho, apresentamos em primeiro lugar um estudo de dois trabalhos de J. P. LaSalle, abordando o comportamento assintótico de sistemas discretos. Em segundo lugar, estudamos a dinâmica de um sistema discreto que depende de um parâmetro l em L, da forma x(n+1) = f(x(n), l). Como uma parte deste objetivo geral, desenvolvemos técnicas para obter estimativas uniformes (em relação ao parâmetro l em L) do atrator quando o sistema for globalmente dissipativo. Esses métodos são baseados em funções auxiliares tipo Liapunov. No final deste trabalho, apresentamos algumas simulações envolvendo sistemas discretos caóticos, como os sistemas de Chua, Hénon, Ikeda, Lorenz e Rössler.; Firstly, in this work, we present a study of part of two works by J. P. LaSalle, concerning with asymptotic behavior of discrete systems. Secondly, we study the dynamics of a discrete system that depends on a parameter l in L, of the form x(n+1) = f(x(n), l). As part of this general purpose, we develop tecniques to obtain uniform estimates (with respect to the parameter l in L) of the attractor when the system is globally dissipative. These methods are based on auxiliary functions of Liapunov type. In the last part of this work we present some simulations envolving chaotic discrete systems...

## Processo de terceirização logística: uma abordagem de dinâmica de sistemas. ; Logistics outsourcing process: a systems dynamics approach.

Arellano Caldeira Franco, Raul
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
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Este estudo tem como objetivo desenvolver um modelo de Dinâmica de Sistemas para analisar e avaliar a dinâmica econômica do processo de terceirização logística visando elaborar políticas que permitam maximizar os ganhos nesse processo e alcançar os retornos positivos desejados pela empresa. Assume-se que a tomada de decisão a favor da terceirização já foi tomada pela empresa. Foram incluídos no modelo desenvolvido os custos anteriores à implantação, denominados como custos ex-ante, e os custos após o início de operações terceirizadas, chamados de ex-post, para entender como todos estes influem no Valor Presente Líquido (VPL) do processo de terceirização logística. O modelo desenvolvido permitiu também simular variações nas políticas de negócios, como redução dos períodos ex-ante à implantação da operação terceirizada ou no monitoramento interno dos funcionários da empresa no mesmo período ex-ante, a fim de conhecer se os resultados financeiros esperados desse processo foram atingidos. Também permite entender melhor o impacto dos juros ou da inflação no processo de terceirização logística, ao poder-se alterar estes parâmetros e entender quando estes têm um impacto destrutivo menor. Buscar-se-á...

## A aplicação de um modelo de simulação para o gerenciamento de projetos: um estudo de caso utilizando a dinâmica de sistemas.; The application of a simulation model to project management: a case study using system dynamics.

Santos, Aldren Montenegro dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
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## Uso da simulação de sistemas dinamicos para analise de logistica hospitalar : gestão integrada de estoque e capacidade; Systems dynamics simulation in hospital logistics : stock and capacity management integrated vision

Janaina Antonino Pinto
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
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## Relaxation and Dephasing in Open Quantum Systems Time-Dependent Density Functional Theory: Properties of Exact Functionals from an Exactly-Solvable Model System

Tempel, David Gabriel; Aspuru-Guzik, Alán
Tipo: Artigo de Revista Científica
Português
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The dissipative dynamics of many-electron systems interacting with a thermal environment has remained a long-standing challenge within time-dependent density functional theory (TDDFT). Recently, the formal foundations of open quantum systems time-dependent density functional theory (OQS-TDDFT) within the master equation approach were established. It was proven that the exact time-dependent density of a many-electron open quantum system evolving under a master equation can be reproduced with a closed (unitarily evolving) and non-interacting Kohn–Sham system. This potentially offers a great advantage over previous approaches to OQS-TDDFT, since with suitable functionals one could obtain the dissipative open-systems dynamics by simply propagating a set of Kohn–Sham orbitals as in usual TDDFT. However, the properties and exact conditions of such open-systems functionals are largely unknown. In the present article, we examine a simple and exactly-solvable model open quantum system: one electron in a harmonic well evolving under the Lindblad master equation. We examine two different representitive limits of the Lindblad equation (relaxation and pure dephasing) and are able to deduce a number of properties of the exact OQS-TDDFT functional. Challenges associated with developing approximate functionals for many-electron open quantum systems are also discussed.; Chemistry and Chemical Biology; Physics

## 18.385 Nonlinear Dynamics and Chaos, Fall 2002; Nonlinear Dynamics and Chaos

Rosales, Rodolfo
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Português
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Nonlinear dynamics with applications. Intuitive approach with emphasis on geometric thinking, computational and analytical methods. Extensive use of demonstration software. Topics: Bifurcations. Phase plane. Nonlinear coupled oscillators in biology and physics. Perturbation, averaging theory. Parametric resonances, Floquet theory. Relaxation oscillations. Hysterises. Phase locking. Chaos: Lorenz model, iterated mappings, period doubling, renormalization. Fractals. Hamiltonian systems, area preserving maps; KAM theory.

## System Dynamics Modeling of Humanitarian Relief Operations

Gonçalves, Paulo
Fonte: Cambridge, MA; Alfred P. Sloan School of Management, Massachusetts Institute of Technology Publicador: Cambridge, MA; Alfred P. Sloan School of Management, Massachusetts Institute of Technology
Tipo: Trabalho em Andamento
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Against the backdrop of over two hundred thousand people dead or missing and millions of people homeless after China’s massive earthquake and Myanmar devastating cyclone, forecasts estimate that natural and manmade disasters are likely to increase five-fold both in number and impact over the next 50 years. Hence, the need for disaster relief provided by humanitarian organizations during disasters should continue to increase. At the same time, humanitarian organizations face increased challenges scaling capacity, improving operational efficiency, reducing staff turnover, improving institutional learning, satisfying increasingly demanding donors, and operating in increasingly challenging environments, with poor or inexistent infrastructure, high demand uncertainty and little time to prepare and respond. To address such challenges, managers in humanitarian organizations must understand the complexity that characterizes humanitarian relief efforts to learn how to design and manage complex relief operations. Yet, learning in such complex and ever changing environments is difficult precisely because managers seldom confront many of the consequences of their most important decisions. Effective learning in such environments requires methods and tools that allow managers to capture important feedback processes...

## System transition : dynamics of change in the US air transportation system; Dynamics of change in the US air transportation system; Dynamics of change in the US air transportation system

Mozdzanowska, Aleksandra L. (Aleksandra Ludmila), 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 244 p.
Português
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The US Air Transportation System is currently facing a number of challenges including an increasing demand for travel and growing environmental requirements. In order to successfully meet future needs, the system will need to transition from its current state using a combination of technology, infrastructure, procedure, and policy changes. However, the complexities of the air transportation system make implementing changes a challenge. In particular, the multi-stakeholder nature of the system poses a significant barrier to transition. Historically, many changes in the air transportation system were driven by safety concerns and implemented following accidents which provided the momentum to overcome transition barriers. As a result of past changes, the system has become increasingly safe resulting in the emergence of new drivers for change. Security has emerged as a driver following the terrorist attacks of 9/11/2001 in the US and a number of system changes have since been implemented. Currently, capacity is one of the largest drivers of change. Addressing capacity issues requires solutions that can be accepted by stakeholders, and pass the necessary certification and approval requirements for implementation. The contribution of aviation to global greenhouse gas emissions is also becoming a significant driver for change in the system. The goal of this work is to understand how the air transportation system changes in response to safety...

## New types of knowledge about system dynamics for intelligent control system design.

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This is a thesis by publication. This thesis comprises ten published/submitted journal articles including eight research articles and two review articles. Five of these journal papers have been already published or finally accepted for publication. This thesis, based on research undertaken in the area of intelligent and non-model-based control, aims at broadening knowledge about system dynamics applicable for control system design. Currently, mathematical models of systems, experimental input-output data and experts’ knowledge in the form of fuzzy rules (linguistic expressions) are three types of knowledge about systems dynamics which are employed in control system design. These types of knowledge are used to define the number and the positions of controllers in the control system (architecture of control systems) and/or the mathematical form of controllers (controllers’ structure) and/or controllers’ parameters. Defining control systems at these three levels (architecture, controllers’ structure and parameters) forms the process of control design. In the area of non-model-based control, some cases of unexpected poor control performance were observed by the author. For instance, neuro-predictive method controls process plants very well. This method is based on input-output data. Thus...

## Systems Dynamics (under construction)

Tipo: Outros
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One example of systems dynamics applied to insurgency is discussed in Kendall’s thesis, pages 25-28: Kilcullen, David. (2005). Countering Global Insurgency. The Journal of Strategic Studies, 28:4, 597-617. http://smallwarsjournal.com/documents/kilcullen.pdf ??? Basic references for systems dynamics: Forrester, J. W. (1961). Industrial Dynamics. Cambridge, Mass.: M.I.T. Press, 13-42.

## A systems approach to modeling drivers of conflict and convergence in the Asia-Pacific region in the next 5-25 years

Whitcomb, Clifford A.; Abdel-Hamid, Tarek; Porter, Wayne; Beery, Paul T.; Wolfgeher, Christopher; Parker, Gary W.; Szczerbinski, Michael
Tipo: Relatório
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This project is part of a Strategic Multi-Layer Assessment (SMA) for the U.S. Pacific Command (PACOM). This SMA provides planning support for complex operational imperatives requiring multi-agency, multi-disciplinary solutions that are not currently within core PACOM competencies. The Naval Postgraduate School’s (NPS) contribution overcomes the current conceptualization limitations by using a Systems Dynamics (SD) viewpoint to examine U.S.–China relations. This approach employs systems thinking and systems dynamics methodologies to analyze the policy structures of major issues of concern common to U.S. and China which result in non-linear and dynamic behavior over time. The SD model developed is composed of four sectors of common concern: energy demand and resources, demographics and stability, economics, and military actions. These sector models are used to model tension between the U.S. and China over the next 25 years. Tension was chosen as an underlying surrogate to overall U.S.–China relations. A simulation tool was developed assist policy makers in better understanding how the system's variables are related, how they influence one another, and how they are influenced by the system's external environment. The simulation tool also supports decision / policy making by allowing analysts to explore the effects of these variables on potential futures.; Assistant Secretary of Defense for Research & Engineering/Rapid Fielding Directorate/Rapid Reaction Technology Office; Assistant Secretary of Defense for Research & Engineering/Rapid Fielding Directorate/Rapid Reaction Technology Office (ASD R&E/RFD/RRTO).

## Contributions to attitude dynamics of the Petite Amateur Navy Satellite (PANSAT)

Graswald, Markus; Panholzer, Rudolf
Tipo: Relatório Formato: 204 p.
Português
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Approved for public release; distribution is unlimited; The purpose of this technical report is to document the theoretical and practical aspects of the attitude dynamics of the Petite Amateur Navy Satellite (PANSAT). PANSAT is an experimental, small, low cost, communications satellite that was designed and built by officer students supported by the Space Systems Academic Group at the Naval Postgraduate School in Monterey, California. The satellite was deployed during the STS 95 mission into a low-Earth orbit providing an altitude of about 300 nautical miles and an inclination of 28.50 on October 30, 1998. The dynamics of the non-stabilized spacecraft are modeled by the equations of rotational motion incorporating environmental torques and considering several reference systems. The initial state of motion and attitude as launched from the Space Shuttle as well as telemetry data received after deployment are investigated in order to obtain an understanding on the satellite's actual dynamics and attitude. Visualization tools are provided to display the attitude of PANSAT at time of deployment and the roll-rate relative to the Sun.; "This report was prepared for and funded by the Naval Postgraduate School, Space Systems Academic Group."

## Supply chain dynamics

Barbosa, Ricardo Wagner Lopes, 1976-; Fan, Edward, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 138 p.; 6921979 bytes; 6940348 bytes; application/pdf; application/pdf
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The strong bargaining power of major retailers and the higher requirements for speed, service excellence and customization have significantly contributed to transform the Supply Chain Management. These increasing challenges call for an integrated and dynamic Supply Chain Management and for a better integration and alignment with key customers, in order to reduce the firm's time-to-market and build competitive advantage. The thesis aims at providing the partner company, a major player in the consumer goods industry, with a more robust and efficient vendor managed inventory practice, so that the partner can determine the optimum inventory level to satisfy turnover, service level and lead time requirements, whereas minimizing lost sales and total costs in the system. The team developed a Supply Chain Dynamics framework to help the partner to establish new service level strategies, strongly oriented to the strategic importance of its products and customers, and to map the key system-wide drivers that impact the overall number of inventory turns, service level and total costs. Additionally, in order to run simulations and estimate the outcomes of the proposed recommendations, the team developed a "Multi-Echelon" simulator and used a commercial "Supply Chain Dynamics" simulator.; by Ricardo Wagner Lopes Barbosa [and] Edward Fan.; Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology...

## A system dynamics approach to supplier partnership management in supply chain

Zhai, Lihua, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 62 leaves; 2828040 bytes; 2833777 bytes; application/pdf; application/pdf
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To be competitive and quick-to-market in today's global marketplace, Electronic Manufacturing Service (EMS) providers should focus on their core competencies, partnership relationships and continuous improvements. As Original Equipment Manufacturers (OEMs) Customers shift their focus on marketing and product development, EMS providers have been assuming the leading role to develop creative manufacturing solutions based on the core competencies in their supply chains. A tightly-coupled and synergistic relationship with OEM customers and key components suppliers is critical to EMS providers' success. This thesis focuses on applying system dynamics approach to supplier partnership management at FSJC, a top player in EMS industry, with the aim of gain deeper understanding on dynamics within FSJC's supply chain network and between suppliers and FSJC. We find out that to maintain its market position, FSJC must concentrate on small number of qualified suppliers and put effort to build strong partnership with these suppliers. This requires a better understanding of the impact of key parameters of partnership and manufacturing process of both suppliers and FSJC. Developing this sort of understanding can help FSJC continue to provide worldwide responsiveness to its customers by improving time-to-market...

## Power Systems as Dynamic Networks

Hill, David; Chen, Guanrong
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
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The theory of power systems dynamics has been developed largely from detailed studies of the dynamics of simple system structures with emphasis on the effects of modeling details of the dynamics. In contrast, the recent study in the science of complex net

## Groups and nonlinear dynamical systems. Chaotic dynamics on the SU(2)xSU(2) group

Kowalski, K.; Rembielinski, J.
Tipo: Artigo de Revista Científica
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In our previous paper: K. Kowalski and J. Rembieli\'nski, Groups and nonlinear dynamical systems. Dynamics on the SU(2) group, Physica D 99, 237 (1996), we introduced an abstract Newton-like equation on a general Lie algebra such that submanifolds fixed by the second-order Casimir operator are attracting set. The corresponding group parameters satisfy the nonlinear dynamical system having an attractor coinciding with the submanifold. In this work we discuss the case with the $SU(2)\times SU(2)$ group. The resulting second-order system in $R^6$ is demonstrated to exhibit chaotic behaviour.; Comment: 12 pages LaTeX, uses espart.sty and equation.sty; accepted for publication in Chaos, Solitons & Fractals

## Anomalous lifetime distributions and topological traps in ordering dynamics

Castelló, Xavier; Toivonen, Riitta; Eguíluz, Víctor M.; Saramäki, J.; Kaski, K.; San Miguel, Maxi
Fonte: EDP Sciences Publicador: EDP Sciences
Tipo: Artículo Formato: 2373 bytes; 1019158 bytes; text/plain; application/pdf
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6 pages.-- PACS numbers: 64.60.Cn, 87.23.Ge.-- Final full-text version of the paper available at: http://dx.doi.org/10.1209/0295-5075/79/66006.; We address the role of community structure of an interaction network in ordering dynamics, as well as associated forms of metastability. We consider the voter and AB model dynamics in a network model which mimics social interactions. The AB model includes an intermediate state between the two excluding options of the voter model. For the voter model we find dynamical metastable disordered states with a characteristic mean lifetime. However, for the AB dynamics we find a power law distribution of the lifetime of metastable states, so that the mean lifetime is not representative of the dynamics. These trapped metastable states, which can order at all time scales, originate in the mesoscopic network structure.; This work was supported in part by the Finnish Academy of Science and Letters, Vilho, Yrjö and Kalle Väisälä Foundation, Cost Action P10 (COST-STSM-P10-02707), as well as the Academy of Finland, Center of Excellence program 2006-2011. We acknowledge financial support form the MEC (Spain) through project CONOCE2 (FIS2004-00953). XC also acknowledges financial support from a PhD fellowship of the Govern de les Illes Balears (Spain).

## Trends in local newspaper reporting of London cyclist fatalities 1992-2012: the role of the media in shaping the systems dynamics of cycling

Macmillan, Alex; Roberts, Alex; Woodcock, James; Aldred, Rachel; Goodman, Anna
Tipo: Article; accepted version
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This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.aap.2015.10.016; Background: Successfully increasing cycling across a broad range of the population would confer important health benefits, but many potential cyclists are deterred by fears about traffic danger. Media coverage of road traffic crashes may reinforce this perception. As part of a wider effort to model the system dynamics of urban cycling, in this paper we examined how media coverage of cyclist fatalities in London changed across a period when the prevalence of cycling doubled. We compared this with changes in the coverage of motorcyclist fatalities as a control group. Methods: Police records of traffic crashes (STATS19) were used to identify all cyclist and motorcyclist fatalities in London between 1992 and 2012. We searched electronic archives of London?s largest local newspaper to identify relevant articles (January 1992 - April 2014), and sought to identify which police-reported fatalities received any media coverage. We repeated this in three smaller English cities. Results: Across the period when cycling trips doubled in London, the proportion of fatalities covered in the local media increased from 6% in 1992-1994 to 75% in 2010-2012. By contrast...

## A New Approach for Complex Problem Solving: The Independent Systems Dynamics Elicitation Method

Holmberg, Elizabeth
Tipo: Dissertação Formato: 1560425 bytes; application/pdf
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The Systems Dynamics literature demonstrates that individuals have difficulty understanding and working with systems concepts. To model Systems Dynamics (SD), researchers suggest that clients contract with a modeling team to formulate the problem, elicit the mental models of employees at the client, and use software-based simulation tools. This approach is both time-intensive and costly, limiting its use by organizations. This two-part study piloted the Independent Systems Dynamics Elicitation Method (ISDEM), a new method that may be self-administered by teams to reveal individuals' mental models. The first study, a between-subjects design, compared undergraduate participants' responses on the Systems-Based Inquiry Protocol (S-BI) to the ISDEM. Participants reported more relationships and feedback loops using the ISDEM, and obtained significantly higher Systemic Reasoning Level scores. In Study 2, groups of undergraduate participants were asked to brainstorm and develop a collective model of an issue of university interest, using either their typical brainstorming methods, or the ISDEM. Independent coders rated the ISDEM significantly more informative, clear and useful than the control models. In sum, the ISDEM did a significantly better job eliciting individuals' mental models of systems dynamics than traditional measures...