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Model-based systems engineering: a system for traffic & environment; Engenharia de sistemas baseada em modelos: um sistema para o tráfego & ambiente

Ramos, Ana Luísa Ferreira Andrade
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
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The contemporary world is crowded of large, interdisciplinary, complex systems made of other systems, personnel, hardware, software, information, processes, and facilities. The Systems Engineering (SE) field proposes an integrated holistic approach to tackle these socio-technical systems that is crucial to take proper account of their multifaceted nature and numerous interrelationships, providing the means to enable their successful realization. Model-Based Systems Engineering (MBSE) is an emerging paradigm in the SE field and can be described as the formalized application of modelling principles, methods, languages, and tools to the entire lifecycle of those systems, enhancing communications and knowledge capture, shared understanding, improved design precision and integrity, better development traceability, and reduced development risks. This thesis is devoted to the application of the novel MBSE paradigm to the Urban Traffic & Environment domain. The proposed system, the GUILTE (Guiding Urban Intelligent Traffic & Environment), deals with a present-day real challenging problem “at the agenda” of world leaders, national governors, local authorities, research agencies, academia, and general public. The main purposes of the system are to provide an integrated development framework for the municipalities...

Global parameter identification and control of nonlinearly parameterized systems

Kojić, Aleksandar M., 1974-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 114 leaves; 6857412 bytes; 6857170 bytes; application/pdf; application/pdf
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Nonlinearly parameterized (NLP) systems are ubiquitous in nature and many fields of science and engineering. Despite the wide and diverse range of applications, there exist relatively few results in control systems literature which exploit the structure of the nonlinear parameterization. A vast majority of presently applicable global control design approaches to systems with NLP, make use of either feedback-linearization, or assume linear parameterization, and ignore the specific structure of the nonlinear parameterization. While this type of approach may guarantee stability, it introduced three major drawbacks. First, they produce no additional information about the nonlinear parameters. Second, they may require large control authority and actuator bandwidth, which makes them unsuitable for some applications. Third, they may simply result in unacceptably poor performance. All of these inadequacies are amplified further when parametric uncertainties are present. What is necessary is a systematic adaptive approach to identification and control of such systems that explicitly accommodates the presence of nonlinear parameters that may not be known precisely. This thesis presents results in both adaptive identification and control of NLP systems. An adaptive controller is presented for NLP systems with a triangular structure. The presence of the triangular structure together with nonlinear parameterization makes standard methods such as back-stepping...

BioJADE : a design and simulation tool for synthetic biological systems; Design and simulation tool for synthetic biological systems

Goler, Jonathan Ari, 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 85 p.; 3341552 bytes; 3350832 bytes; application/pdf; application/pdf
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The next generations of both biological engineering and computer engineering demand that control be exerted at the molecular level. Creating, characterizing and controlling synthetic biological systems may provide us with the ability to build cells that are capable of a plethora of activities, from computation to synthesizing nanostructures. To develop these systems, we must have a set of tools not only for synthesizing systems, but also designing and simulating them. The BioJADE project provides a comprehensive, extensible design and simulation platform for synthetic biology. BioJADE is a graphical design tool built in Java, utilizing a database back end, and supports a range of simulations using an XML communication protocol. BioJADE currently supports a library of over 100 parts with which it can compile designs into actual DNA, and then generate synthesis instructions to build the physical parts. The BioJADE project contributes several tools to Synthetic Biology. BioJADE in itself is a powerful tool for synthetic biology designers. Additionally, we developed and now make use of a centralized BioBricks repository, which enables the sharing of BioBrick components between researchers, and vastly reduces the barriers to entry for aspiring Synthetic Biologists.; by Jonathan Ari Goler.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology...

Real options "in" projects and systems design : identification of options and solutions for path dependency

Wang, Tao, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 337 p.; 14812215 bytes; 14855847 bytes; application/pdf; application/pdf
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This research develops a comprehensive approach to identify and deal with real options in" projects, that is, those real options (flexibility) that are integral parts of the technical design. It represents a first attempt to specify analytically the design parameters that provide good opportunities for flexibility for any specific engineering system. It proposes a two-stage integrated process: options identification followed by options analysis. Options identification includes a screening and a simulation model. Options analysis develops a stochastic mixed-integer programming model to value options. This approach decreases the complexity and size of the models at each stage and thus permits efficient computation even though traditionally fixed design parameters are allowed to vary stochastically. The options identification stage discovers the design elements most likely to provide worthwhile flexibility. As there are often too many possible options for systems designers to consider, they need a way to identify the most valuable options for further consideration, that is, a screening model. This is a simplified, conceptual, low-fidelity model for the system that conceptualizes its most important issues. As it can be easily run many times...

Feasibility and design of blast mitigation systems for naval applications using water mist fire suppression systems

Kitchenka, Julie A
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 127 leaves; 5651918 bytes; 5657215 bytes; application/pdf; application/pdf
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The recent trend of using fine water mist systems to replace the legacy HALON- 1301 fire suppression systems warrants further study into other applications of the water mist systems. Preliminary research and investigation indicates that fine mists (20-25 pm droplet size) may reduce peak overpressures of a shock wave traveling through a space. Such pressure reductions could be used to mitigate the destructive effects of a shock wave (initiated by an explosive device) traveling through a structure. Currently these blast mitigation effects have only been demonstrated in small-scale shock tube tests and computer simulations. Uncertainty exists as to the scalability of such a system. The intention of this research is to investigate the applicability of such a blast mitigation system for shipboard use. Study into the degree of mitigation necessary to make a system practical for shipboard installation was conducted. In addition, a theoretical study of the mechanisms of blast mitigation using water mists was completed. Preliminary design of a full-scale system was examined.; (cont.) Given the recent trend toward tumblehome hull forms in future Naval Combatant designs, there exists strong applicability of this system in the "dead" spaces created by the shaping of the tumblehome hull. Further work is needed in numerical modeling and laboratory testing of specific phases of the mitigation. The end goal is a feasible design of a blast mitigation system to be used in the outermost spaces of Naval Combatants to protect interior vital system spaces.; by Julie A. Kitchenka.; Thesis (Nav. E.)--Massachusetts Institute of Technology...

2.019 Design of Ocean Systems I (13.017), Spring 2002; Design of Ocean Systems I (13.017)

Consi, Thomas R., 1956-; Hover, Franz S.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
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A two-semester subject sequence (of which this is the first half) that demonstrates the design process through its application to a working model-scale ocean system. Emphasis is on carrying out the design and implementation of the system, including demonstration of its operation in the marine environment. Spring Term: Introduction to the design process and its application to ocean engineering. Design project with students developing system definition and completing its preliminary design. Students are instructed in the design process, embedded systems programming and interfacing techniques, sensors, actuators, and the control of marine systems. Communications skills are honed through written and oral reports and engineering ethics are discussed. Fall Term: Students work as a group to design, plan, construct, test, and operate the model-scale ocean system defined in 13.017. Special emphasis is placed on testing the system in the marine environment and analyzing its performance in relation to the original system specification. The social aspects of engineering are discussed including group dynamics and time management. The specific design project varies from year to year and is announced to the students on the first day of class in 13.017.

13.017 Design of Ocean Systems I, Spring 2003; Design of Ocean Systems I

Consi, Thomas R., 1956-; Hover, Franz S.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
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A two-semester subject sequence (of which this is the first half) that demonstrates the design process through its application to a working model-scale ocean system. Emphasis is on carrying out the design and implementation of the system, including demonstration of its operation in the marine environment. Spring Term: Introduction to the design process and its application to ocean engineering. Design project with students developing system definition and completing its preliminary design. Students are instructed in the design process, embedded systems programming and interfacing techniques, sensors, actuators, and the control of marine systems. Communications skills are honed through written and oral reports and engineering ethics are discussed. Fall Term: Students work as a group to design, plan, construct, test, and operate the model-scale ocean system defined in 13.017. Special emphasis is placed on testing the system in the marine environment and analyzing its performance in relation to the original system specification. The social aspects of engineering are discussed including group dynamics and time management. The specific design project varies from year to year and is announced to the students on the first day of class in 13.017.

A systems-theoretic security model for large scale, complex systems applied to the US air transportation system; systems-theoretic security model for large scale, complex systems applied to the US air transportation system

Laracy, Joseph R. (Joseph Raymond)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 132 p.
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Classical risk-based or game-theoretic security models rely on assumptions from reliability theory and rational expectations economics that are not applicable to security threats. Additionally, these models suffer from serious deficiencies when they are applied to software-intensive, socio-technical systems. Recent work by Leveson in the area of system safety engineering has led to the development of a new accident model for system safety that acknowledges the dynamic complexity of accidents. Systems-Theoretic Accident Models and Processes (STAMP) applies principles from control theory to enforce constraints on hazards and thereby prevent accidents. Appreciating the similarities between safety and security while still acknowledging the differences, this thesis extends STAMP to security problems. In particular, it is applied to identify and mitigate the threats that could emerge in critical infrastructures such as the Air Transportation System. Furthermore, recommendations are provided to assist systems engineers and policy makers in securely transitioning to the Next Generation Air Transportation System (NGATS).; by Joseph R. Laracy.; Thesis (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, 2007.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 129-132).

Knowledge integration for problem solving in the development of complex aerospace systems

Haddad, Marc George
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 279 p.
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The development of complex products requires widespread knowledge interactions among a significant number of individuals and teams designing numerous interrelated components. Increasing product complexity typically leads to a corresponding increase in the types and sources of knowledge that need to be tapped during development, and a common strategy for managing product complexity is to outsource parts and components to external suppliers. As a result, the knowledge required for development is increasingly specialized and distributed across multiple boundaries spanning large-scale organizational networks, thus requiring the subsequent integration of this knowledge in order to accomplish the development task. A framework for knowledge integration in the development of complex systems in a large-scale organizational context is proposed in this thesis using an extensive review of the pertinent literature. The framework consists of the main channels, strategies, practices and mechanisms most commonly used to transfer, share and apply knowledge in the course of complex technical problem solving. The framework is progressively refined using empirical data collected through several rounds of interviews and a questionnaire instrument administered across three major aircraft programs in the defense aerospace industry. We find that knowledge integration in routine problem solving situations is most efficiently and effectively accomplished through extensive transfer and sharing of codified information using formal mechanisms such as information systems...

Systems engineering in practice : the application of systems engineering principles to the development of a hydraulic control system for an automatic transmission; Application of systems engineering principles to the development of a hydraulic control system for an automatic transmission

Aquaro, Matthew
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 71 p.
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Product development in the automotive industry has evolved around the design of components. The organization is established around components and people have a very component centric perspective on problem solving. This has led to local optimization of individual components, while the larger system spirals out of control. The penalty is often measured in terms of development time and cost. New programs are given autonomy to make independent choices without regard for what other programs are doing, which leads to a wide variety of architectures put into place. Program managers and functional managers have different prioritizations. Furthermore, new designs are provided by a separate organization from the group responsible for implementation. They have a very different value system and are unaware of the difficulties experienced in the implementation phase. This type of practice leads to programs nearing production deadlines with poorly optimized systems. Engineers must relearn due to the lack of standardization across program. The team absorbs additional resources from within to fix issues prior to launch. The robbing of resources leads to delays in subsequent programs and the cycle repeats itself. These issues are partly cultural, part organizational...

Extending the hierarchical systems knowledge representation framework : interfacing with geographic information systems

Phillips, Reesa Brooke
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 108 p.
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This thesis presents the design and implementation of a geographic information systems framework in which engineering systems can be created and analyzed. This framework extends the hierarchical systems knowledge representation framework to allow geospatial information to be attributed to model objects and viewed within geographic information system tools. The addition of geospatial information allows analysts to use spatial analysis to better learn about engineering systems.; by Reesa Brooke Phillips.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.; Includes bibliographical references (p. 107-108).

Expeditionary warfare : force protection

Higgins, Eric John; Higgs, Ronald Leroy; Parkins, Gregory Rodger; Tionquiao, Vincent S; Wells, Christopher Kevin
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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Includes supplementary material.; In 2003, the Systems Engineering and Analysis students were tasked to develop a system of systems conceptual solution to provide force protection for the Sea Base conceptualized in the 2002 Expeditionary Warfare study. The Systems Engineering and Analysis Team used the Systems Engineering and Management process as the primary methodology to complete this multidisciplinary task. Survivability was identified as the most critical factor for evaluating the protection of the Sea Base and its transport assets. Threats to the Sea Base were reviewed, analyzed, and prioritized. System design and analysis focused on preliminary analyses of various sensors, search concepts, and weapons. These preliminary analyses identified capability gaps that were translated into functional concepts and proposed architectures for detailed modeling and analysis. These proposed architectures were identified as either Point or Distributed. In order to adequately determine the relative performance of the proposed architectures generated by the team, a thorough and systematic design of experiments was developed and applied in the Naval Simulation System and EXTEND. Based on the results obtained, the Systems Engineering and Analysis Team determined that a Distributed Sensor and Weapons architecture would significantly increase the survivability of future Expeditionary Warfare forces.

Cp3s system engineering: a primer

Purnell, John S.
Fonte: Monterey California. Naval Postgraduate School Publicador: Monterey California. Naval Postgraduate School
Tipo: Tese de Doutorado
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The components of a command, control and communications (C3) system have evolved from highly sophisticated forms of electronic hardware and software innovations. Modern C3 systems such as the Joint Tactical Information Data System (JTIDS) or Airborne Warning and Control System (AWACS), incorporate a wide assortment of computers, CRT displays, communications equipment and data processing systems. These systems are developed and integrated through the means of highly proficient system engineering processes. This thesis addresses the elements of basic creative and design processes that contribute to systems engineering methodology. This thesis discusses the various stages of the system engineering process which serve to integrate the design and development of such large scale systems. A case study, ?CINCCENT Ground Mobile Command Post,? is presented as an example of the system engineering process

Control of Total Ownership Costs of DoD Acquisition Development Programs Through Integrated Systems Engineering Processes and Metrics

Paul Montgomery; Ron Carlson
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
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Proceedings Paper (for Acquisition Research Program); Many DoD weapon systems acquisition programs are exceeding their original estimates for total ownership costs. There are probably many contributing factors to this cost growth, but is Systems Engineering (SE) one of them? How can systems engineering processes, methods, and practices be improved to better control total ownership cost growth in DoD acquisition programs? This paper discusses research in developing an understanding of how SE can be optimized for developing high confidence estimates and better control of acquisition program total ownership costs (TOC). Although this research is in the very early stages, we discuss the technical approach to investigating systems engineering methods and practices related to TOC as executed at one of the Navy's major system acquisition commends (Naval Air Systems Command-NAVAIR). We discuss very preliminary findings and set the stage for further research results.

System architecture for a military weapon system development process to integrate design and the manufacturing process for use by a government technical development agency

Lyon, Charles Scott
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
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Approved for public release; distribution is unlimited; This thesis integrates Concurrent Engineering (CE) or Design for Manufacturability into a government research and development agency. For new weapon concepts originating within government, CE is difficult to apply effectively within the policies and bureaucratic structures. This project describes a proposed structure for a development agency, using fuzes and the U.S. Army Fuze Division as a basis. Although the Fuze Division’s application of CE to date has been effective, much potential remains unreachable due to the Department of Defense (DOD) acquisition policy, with its series of incremental design phases. The proposed organization is arranged in teams according to professional/ engineering specialty. In addition, manufacturing engineering and fuze systems engineering groups are introduced. Integrated Product Teams managed by a member of the systems engineering group would draw from each of the specialized groups. This project illustrates that an agency can be organized to support and promote effective concurrent engineering within the limitations of the DOD acquisition policy. With this structure, manufacturing considerations will be deliberately integrated into every new fuze design...

Bio-Mechatronics: From Insects to In-Vivo Mechatronics

Vaidyanathan, Ravi
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Poster
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The Department of Automatic Control & Systems Engineering is pleased to announce the following seminar: Bio-Mechatronics: From Insects to In-Vivo Mechatronics Dr Ravi Vaidyanathan Department of Mechanical Engineering Imperial College Wednesday, 25th September 2013 at 14:00, LT02, Sir Henry Stephenson Building; Mechatronics is the synergistic combination of precision engineering, electronic control, and systems thinking in the design of products and manufacturing processes. Bio-Mechatronics may be viewed as its extension fused with influence from biological systems; i.e. mechatronic systems designed based on inspiration from neural and physiological systems. In animals, for example, intrinsic properties of the musculoskeletal system augment the neural stabilization of the organism for an array of critical of functions. Modeling this hierarchical coupling for implementation in robotic systems has spurred innovation in medicine, cybernetics, and mobile robots.

A discourse in human systems integration

Tvaryanas, Anthony P.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Formato: xxxii, 608 : ill. (chiefly col.), 1 col. map 28 cm.
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This dissertation tackles, head on, two fundamental questions: What is human systems integration (HSI) and how should one think about HSI problems? The objective was to develop a coherent systems method to improve the integration of HSI domains to create sustainable systems while preserving system stakeholder preferences. This dissertation addresses these questions by accomplishing two things: 1) extracting the lessons learned from a historical analysis of the emergence of HSI both as a philosophy and as a Defense Department program, and 2) using those lessons to characterize and illustrate a technical approach to addressing HSI considerations early in an acquisition process. It is shown that the discourse on general systems that occurred over the latter half of the twentieth century, coupled with pressing organizational factors within the U.S. Army, were the principal forces that shaped and drove the emergence and formal recognition of HSI. As determined from this historical analysis, HSI involves the integration of the behavioral sciences, human factors engineering, and operations research to more broadly represent human considerations in early weapon system analyses and the products that evolve from these analyses. Inclusion of HSI in system analyses necessitates a holistic perspective of the performance and economic trade space formed by the synthesis of the HSI domains. As a result...

Uma metodologia unificada para o desenvolvimento de sistemas orientados a agentes; A unified methodology for the development of agent-oriented systems

Claudia Filomena Bratficher Dario
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/07/2005 Português
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Este trabalho propõe uma Metodologia Unificada para o desenvolvimento de sistemas orientados a agentes. A elaboração desta metodologia foi realizada a partir de um estudo do papel do agente dentro da Engenharia de Software e da análise de diversas metodologias orientadas a agentes encontradas na literatura, enfocando-se principalmente em três destas: MaSE (Muitiagent Systems Engimering Metkodoiogy), Prornetheus e Tropos, além da linguagem de modelagem AÜML {Agem Vnijied Modeling Language). A Metodologia Unificada proposta visa aproveitar o que há de melhor nestas metodologias, buscando elementos comuns a todas elas, de modo análogo ao que ocorreu com a metodologia unificada (RUP - Raiional Unified Process) em sistemas orientados a objetos. Para validar a Metodologia Unificada e analisar as demais metodologias, um estudo de caso foi modelado. A Metodologia Unificada se mostrou eficiente no projeto, documentação e construção de sistemas multi-agentes, sendo considerada uma metodologia detalhada e mais completa por cobrir os estágios de especificação de requisitos, de análise e de projeto no desenvolvimento de software orientados a agentes; This work proposes a Unified Methodology for the development of agent-oriented systems. The methodology was elaborated based on a study of agent's role within software engineering and the analysis of different agent-based software development methodologies found in the literature...

A Model-Driven Approach to Systems-of-Systems Engineering

Flint, Shayne
Fonte: Conference Organising Committee Publicador: Conference Organising Committee
Tipo: Conference paper
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Traditional engineering aims to solve problems by building, operating, maintaining and retiring systems of various kinds. However, problems usually emerge within dynamically complex environments of co-evolving technology, people, processes and other problems. Because of this, individual problems are often difficult to isolate and independently solve. It is generally accepted that these dynamically complex sets of interacting problems, or Problem Situations, are best dealt with by improving the whole rather than by attempting to solve individual problems. In recent years our research group has been thinking about the nature of engineering within such environments and has developed Aspect-Oriented Thinking (AOT): a novel model-driven engineering approach to continuous learning and improvement within dynamically complex environments. In this paper I provide an overview of AOT and show how it might form the foundation of an effective systems-of-systems engineering methodology.

Variability and Evolution in Systems of Systems

Botterweck, Goetz
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/11/2013 Português
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In this position paper (1) we discuss two particular aspects of Systems of Systems, i.e., variability and evolution. (2) We argue that concepts from Product Line Engineering and Software Evolution are relevant to Systems of Systems Engineering. (3) Conversely, concepts from Systems of Systems Engineering can be helpful in Product Line Engineering and Software Evolution. Hence, we argue that an exchange of concepts between the disciplines would be beneficial.; Comment: In Proceedings AiSoS 2013, arXiv:1311.3195