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Integrated model-based design and simulation of critical embedded systems; Projeto e simulação integrados baseados em modelos para sistemas embarcados críticos

Ferreira, Ronaldo Rodrigues
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Trabalho de Conclusão de Curso Formato: application/pdf
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A partir da introdução do sistema de controle fly-by-wire nos programas Concorde e A320 de aviação civil, a complexidade dos sistemas aviônicos embarcados aumenta constantemente. A operação dos aviões atuais e futuros é fortemente dependente para seu funcionamento dos seus sistemas aviônicos embarcados. A inovação em termos de computação dessa aviônica embarcada nos permitiu aperfeiçoar a segurança de vôo, bem como a relação entre a aeronave e o ambiente, voando de maneira mais ecologicamente consciente, além de reduzir custos e permitir melhor sustentabilidade para as companhias aéreas. Com o aumento da complexidade devido à constante integração de inovação na aviônica embarcada, as técnicas de Engenharia de Sistemas empregadas atualmente no desenvolvimento desses sistemas estão se tornando insuficientes para gerenciar os requisitos e a dinâmica existentes no projeto, no desenvolvimento e na produção de uma aeronave. Duas atividades que mais sofrem a pressão com o aumento da complexidade são o projeto e a simulação dos sistemas aviônicos embarcados. Ao projeto compete o desenvolvimento dos equipamentos aviônicos, atendendo aos requisitos dos stakeholders. À simulação compete a validação e o refinamento do projeto de um equipamento...

Status report on estimation and statistical analysis of spatially distributed random processes; Estimation and statistical analysis of spatially distributed random processes.

Fonte: Laboratory for Information and Decision Systems, Massachusetts Institute of Technology Publicador: Laboratory for Information and Decision Systems, Massachusetts Institute of Technology
Formato: v.; application/pdf
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prepared by: Bernard C. Levy, Alan S. Willsky.; Prepared for Systems Theory and Operations Research Program, Division of Electrical, Computer, and Systems Engineering, National Science Foundation under NSF Grant ECS-8012668.; Description based on: Nov.1, 1980/June 30, 1981.

Towards a Theory of Complicatedness: Framework for Complex Systems Analysis and Design

Tang, Victor; Salminen, Vesa
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Trabalho em Andamento Formato: 251553 bytes; application/pdf
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Global, dynamic, and competitive business environment has increased the complexity in product, service, operational processes and human side. Much engineering effort goes into reducing systems complexity. We argue that the real issue is reducing complicatedness. This is an important distinction. Complexity can be a desirable property of systems provided it is architected complexity that reduces complicatedness. Complexity and complicatedness are not synonyms. Complexity is an inherent property of systems; complicatedness is a derived function of complexity. We introduce the notion of complicatedness of complex systems, present equations for each and show they are separate and distinct properties. To make these ideas actionable, we present a design methodology to address complicatedness. We show examples and discuss how our equations reflect the fundamental behavior of complex systems and how our equations are consistent with our intuition and system design experience. We discuss validation experiments with global firms and address potential areas for further research. We close with a discussion of the implications for systems design engineers. As engineers, we believe our strongest contributions are to the analysis, design, and managerial practice of complex systems analysis and design. We illustrate the difference between complexity and complicatedness. Relative to a manual transmission...

Large scale C3 systems : experiment design and system improvement

Martin, Philippe J. F
Fonte: Laboratory for Information and Decision Systems, Massachusetts Institute of Technology; Massachusetts Institute of Technology Publicador: Laboratory for Information and Decision Systems, Massachusetts Institute of Technology; Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 106 p.; 6395878 bytes; 6395636 bytes; application/pdf; application/pdf
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Philippe J. F. Martin.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.; Includes bibliographical references (p. 105-106).; Research supported by the Joint Directors of Laboratories through the Office of Naval Research. N00014-85-K-0782

Diagnostic indicators for shipboard systems using non-intrusive load monitoring

DeNucci, Thomas W
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 98 leaves; 4572439 bytes; 4576496 bytes; application/pdf; application/pdf
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Field studies have demonstrated that the Non-Intrusive Load monitor (NILM) can provide real-time indication of the condition of electro-mechanical systems on board naval vessels. Results from data collected from engineering systems on board USCGC SENECA (WMEC-906), a 270-foot U.S. Coast Guard cutter, indicate that the NILM can effectively identify faults, failures and deviations from normal operating conditions on numerous shipboard engineering systems. Data collected from the sewage system identified metrics that can be applied, for example, to cycling systems (high pressure air, hydraulic systems, etc.) to differentiate between periods of heavy usage and fault conditions. Sewage system variability and randomness was minimized by employing a MATLAB simulation designed to permit exploration of system behavior that might not have been exposed during other conditions. Simulation data suggests that the presence, location and magnitude of a spike in the pump run distribution indicated the presence of a leak. Data from the actual shipboard system, when subjected to a quantifiable leak, displayed the same behavior. Data collected from the Auxiliary Seawater (ASW) System indicated that the NILM is able to predict the failure of a flexible coupling linking the pump and motor components.; (cont.) The ASW motor-pump system was modeled using a 5th order induction motor simulation to explore the electro-mechanical relationships between the motor...

Multiobjective collaborative optimization of systems of systems; Multi objective collaborative optimization of systems of systems

Wolf, Robert A. (Robert Allen)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 166 p.; 9303014 bytes; 9309978 bytes; application/pdf; application/pdf
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Concept studies for warship designs typically focus on ship performance characteristics by setting design goals for such things as speed, range, and cost. However, warships generally operate as part of a larger battle or strike group. Therefore, the designs should be evaluated as part of a system of multiple ship systems since designing each ship individually may result in underutilized and excess equipment and capability; in other words an inefficient design of the system of systems. This thesis examines the simultaneous design of several ships using the sea base concept as an example application of a network of ships working together. The number and characteristics of these ships determine the mission performance of the sea base. To properly design any of the sea base ships, the interrelationships must be included. A mission simulation is used to combine the performance characteristics of different ship designs into a single performance objective: the time to deliver a brigade size combat force to its assigned objectives.; (cont.) To enable the design of multiple ships, collaborative optimization, a multilevel optimization approach, was used to decompose the problem into individual ship design optimizations with system level interfaces controlled by a system of systems optimization algorithm. This allowed each ship to use techniques and algorithms best suited to reach an optimal design without impacting the design approaches used by the other ships. The classical collaborative optimization approach was relaxed to include multiple objectives such as performance and cost...

Enabling systems thinking to accelerate the development of senior systems engineers

Davidz, Heidi L
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 440 p.
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As engineering systems become more complex, the roles involved in developing and managing such systems also become more complex. Thus, there is increasing interest in educating and training engineering professionals to think more systemically. In particular, there is an increasing need to accelerate the development of senior systems engineers. As new educational degree programs in systems rapidly emerge and as companies scurry to establish systems training programs to meet this need, fundamental questions still remain about how systems thinking develops in engineers. Increased understanding of the mechanisms that develop systems thinking will enable effective and efficient development of senior systems professionals. After reviewing related literature, an exploratory and inductive study was designed to gather data on enablers, barriers, and precursors to systems thinking development in engineers. In a field study conducted primarily in the United States aerospace sector, 205 interviews were conducted in 10 host companies. Senior systems engineers were studied to better understand how they developed systems thinking, and information was collected on company procedures for developing systems engineers. Using interview and survey data...

Design and optimization of imaging systems by engineering the pupil function

Bagheri, Saeed, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 159 p.
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It is expected that the ability to accurately and efficiently design an imaging system for a specific application will be of increasing importance in the coming decades. Applications of imaging systems range from simple photography to advanced lithography machines. Perhaps the most important way to make an imaging system meet a particular purpose is to engineer the pupil function of the imaging system. This includes designing a pupil surface and often involves the simultaneous design of a post-processing algorithm. Currently these design processes are performed mostly by using numerical optimization methods. Numerical methods in general have many drawbacks including long processing time and no guarantee that one has reached the global optimum. We have developed analytical approaches in designing imaging systems by engineering the pupil function. Two of the most important merit functions that are used for the analysis of imaging systems are the modulation transfer function (MTF) and the point spread function (PSF). These two functions are standard measures for evaluating the performance of an imaging system. Usually during the design process one finds the PSF or MTF for all the possible degrees of freedom and chooses the combination of parameters which best satisfies his/her goals in terms of PSF and MTF.; (cont.) In practice...

Global optimization of hybrid systems

Lee, Cha Kun
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 353 p.
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Systems that exhibit both discrete state and continuous state dynamics are called hybrid systems. In most nontrivial cases, these two aspects of system behavior interact to such a significant extent that they cannot be decoupled effectively by any kind of abstraction and must be analyzed simultaneously. Hybrid system models are important in many areas of science and engineering, including flip-flops and latching relays, manufacturing systems, air-traffic management systems, controller synthesis, switched systems, chemical process systems, signaling and decision making mechanisms in (biological) cells, robotic systems, safety interlock systems, and embedded systems. The primary focus of this thesis is to explore deterministic methods for the global optimization of hybrid systems. While the areas of modeling, simulation and sensitivity analysis of hybrid systems have received much attention, there are many challenging difficulties associated with the optimization of such systems. The contents of this thesis represent the first steps toward deterministic global optimization of hybrid systems in the continuous time domain. There are various reasons for wanting to solve optimization problems globally.; (cont.) In particular, there are many applications which demand that the global solution be found...

Qualitative knowledge construction for engineering systems : extending the design structure matrix methodology in scope and procedure

Bartolomei, Jason E
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 191 leaves
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This thesis presents a new modeling framework and research methodology for the study of engineering systems. The thesis begins with a formal conceptualization of Engineering Systems based upon a synthesis of various literatures. Using this conceptualization, a new modeling framework is presented called the Engineering Systems Matrix (ESM). The ESM is an improvement to existing system-level modeling frameworks, such as the Design Structure Matrix (DSM), by providing a dynamic, end-to-end representation of an engineering system. In support of this contribution, a new research methodology is presented called Qualitative Knowledge Construction (QKC). QKC can be thought of as a Bayesian-type approach to grounded theory. The methodology integrates qualitative social science with quantitative methods by developing a procedure for translating textual reports of observations, interview transcripts, system documentation, and figures into coded data represented in the ESM. The thesis develops the ESM framework and the QKC methodology in the context of a real world engineering system, a US Air Force miniature uninhabited air vehicle (MAV) product development system.; by Jason E. Bartolomei.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

Engineering the interface between cellular chassis and synthetic biological systems

Canton, Bartholomew (Bartholomew John)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 176 p.
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The aim of my thesis is to help enable the engineering of biological systems that behave in a predictable manner. Well-established techniques exist to engineer systems that behave as expected. Here, I apply such techniques to two aspects of the engineering of biological systems. First, I address the design and construction of standard biological devices in a manner that facilitates reuse in higher-order systems. I describe the design and construction of an exemplar device, an engineered cell-cell communication receiver using standard biological parts (refined genetic objects designed to support physical and functional composition). I adopt a conventional framework for describing the behavior of engineered devices and use the adopted framework to design and interpret experiments that describe the behavior of the receiver. The output of the device is the activity of a promoter reported in units of Polymerases Per Second (PoPS), a common signal carrier. Second, I begin to address the coupling that exists between engineered biological systems and the host cell, or chassis. I propose that the coupling between engineered biological systems and the cellular chassis might be reduced if fewer resources were shared between the system and the chassis. I describe the construction of cellular chassis expressing both T7 RNA polymerases (RNAP) and orthogonal ribosomes that are unused by the chassis but are available for use by an engineered system. I implement a network in which the orthogonal ribosomal RNA and the gene encoding T7 RNAP are transcribed by T7 RNAP. In turn...

Aspect-Oriented Thinking - An approach to bridging the disciplinary divides

Flint, Shayne
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
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Engineering is often described as the application of scientific and technical knowledge to solve problems. In this thesis, I support a more general view that engineering should be treated as a continuous process of learning and action that aims to make well understood improvements within dynamically complex environments of co-evolving social, man-made and natural systems. I argue that this can only be achieved by adopting an approach that systematically develops, manages and integrates the knowledge and expertise of many disciplines to conceive, develop, modify, operate and retire systems. A novel implementation of such an approach, called Aspect-Oriented Thinking, is presented. ¶ Aspect-Oriented Thinking begins with the development and verification of a set of domain Models. Each Domain Model represents knowledge about a separate, autonomous and possibly discipline specific concern or view within a given context. Domain models are developed by engineers, scientists, sociologists, psychologists, lawyers, philosophers, economists and others, using languages and techniques with which they are familiar. Knowledge captured in a set of Domain Models is then woven together, in accordance with a set of separately developed patterns and rules...

Systems Engineering Management and the Relationship of Systems Engineering to Project Management and Software Engineering (presentation)

Boehm, Barry; Conrow, Ed; Madachy, Ray; Nidiffer, Ken; Roedler, Garry
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
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Prepared for the 13th Annual NDIA Systems Engineering Conference October 28, 2010, “Achieving Acquisition Excellence Via Effective Systems Engineering”. Panel: Systems Engineering Management and the Relationship of Systems Engineering to Project Management and Software Engineering

Analysing system of systems performance of a carrier strike group conducting anti-submarine warfare

Paulo, Eugene P.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Tipo: Artigo de Revista Científica
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The operation of US and Allied military forces freely and safely across the world’s oceans remains a paramount goal of the US Navy, often to be carried out through the deployment of a carrier strike group (CSG). This paper examines the need for an improved anti-submarine warfare (ASW) system to protect a CSG, focusing on the design of an ASW system that is able to thwart an attack through effective, timely, and precise engagement based on the use of tactically significant detection, localisation, tracking and classification of threat submarines. This effort results in the development of system functions and objectives, appropriate metrics, an operational concept, several competing physical architectural alternatives, and conduct of trade-off analysis regarding system performance. Primarily, the focus is on the operational performance of the competing physical architectures, which is defined as the need to detect and defeat an enemy submarine during a typical CSG mission. Potential ASW and CSG components are described, as well as an assessment of several alternative ASW systems within the CSG system of systems, a brief operational concept, and the specifics of the performance modelling effort to include results.

Transformação de modelos SysML para UML usando a linguagem ATL

Melo, Marcel da Silva
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
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Devido ao grande aumento da complexidade no desenvolvimento de software nos últimos anos, academia e organizações criaram uma solução racional na engenharia de software, chamada de Engenharia Dirigida por Modelos, que busca suportar o gerenciamento de tal complexidade. A Engenharia Dirigida por Modelos é uma abordagem que move o foco do desenvolvimento de software de código para modelos. A UML é atualmente a linguagem mais utilizada para modelagem de software. Apesar do seu uso intenso em vários domínios de aplicação, a UML apresenta de ciências na modelagem em alguns domínios, como por exemplo Software-Intensive Systems, onde a modelagem de elementos que não são software é de grande importância. Uma das grandes vantagens da UML é a sua ampla capacidade de extensão e adaptação aos diferentes domínios de aplicação usando pro les, como é o caso da SysML. A SysML é um pro le UML e representa uma linguagem de propósito geral usada no domínio de Engenharia de Sistemas. Uma operação importante na Engenharia Dirigida por Modelos é a transformação de modelos, que consiste em um processo automatizado de conversão de um modelo origem para modelo destino. A construção de novas transformações, e o reuso das existentes...

Aligning strategic and information systems planning: a review of navy efforts

Zeiders, Glenn W.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: ix, 121 p.
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Approved for public release, distribution unlimited; The necessity for well-defined, integrated information systems (IS), driven by today's dwindling human, financial, and management resources, makes it essential to plan effectively. This can only be achieved by linking IS planning to the overall strategic plan of the organization. Department of the Navy (DON) IS planning has historically missed the mark in this report. Information Engineering, automated through Computer Aided Software Engineering (CASE) technology, offers significant benefits for improving DON IS planning. Two CASE workbenches, Information Engineering Systems Corporation's USER: Expert Systems and Texas Instruments' Information Engineering Facility, have proven highly effective in automating IE in DON applications.; Lieutenant, United States Navy Reserve

Application of a commercial product development practice to military C4I systems product development

Hoyle, Jeffery W.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xii, 87 p. : ill. ;
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Approved for public release, distribution is unlimited; Successful commercial companies understand that customers are the real experts with regard to their products and services. Bringing customer experiences right into the design shop allows development of best-selling commercial products and services. Companies such as L.L. Bean, Inc. immerse themselves in their customer's experiences during new product development. They travel to their customer's location and listen to them face to face to get the best possible input for essential product requirements and new design ideas. Currently, most military C4I systems product development does not make effective use of customer input. Systems are developed and fielded in accordance with Department of Defense regulations that provide insufficient mechanisms for users to influence product requirements and design. C4I system program managers need additional tools to obtain and translate user needs into system requirements and designs. Harvard Business School has developed an educational program aimed at redesigning product/service development based on the L.L. Bean model. This thesis applies the tenets of that program to submarine C4I systems development and identifies obstacles to and lessons learned from its application to military product development.; Commander...

The micro-foundations of alignment among sponsors and contractors on large engineering projects

McKenna, Nicholas A. (Nicholas Alan)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 273 p.
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Large engineering projects design, engineer and construct much of the world's energy, transportation and defense infrastructure. These large scale engineering endeavors are highly visible, have long lasting impacts and are of major economic significance. Yet despite their importance they frequently suffer from cost overruns and long delays and deliver systems with operational shortcomings. A contributing factor to the challenge of large projects is that the project enterprise is created by separate firms being brought together by the project sponsor, typically via formal contracts. Success requires multiple firms with hundreds (possibly thousands) of engineers working together to efficiently create complex product systems within an environment of high uncertainty. In an attempt to improve project outcomes, sponsors often endeavor to create "alignment" between themselves and their key contractors. In practice, alignment has proved difficult to create and to sustain. This research explores the policies and actions taken by firms that give rise to alignment. The large engineering projects studied for this research were offshore oil and gas field developments. grounded theory method, supplemented by formal dynamic model building, was used to investigate the causal mechanisms that support...

Corporate decision analysis : an engineering approach

Tang, Victor, Ph.D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 331 p.
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We explore corporate decisions and their solutions under uncertainty using engineering methods. Corporate decisions tend to be complex; they are interdisciplinary and defy programmable solutions. To address these challenges, we take an engineering approach. Our proposition is that as in an engineering system, corporate problems and their potential solutions deal with the behavior of systems. Since systems can be studied with experiments, we use Design of Experiments (DOE) to understand the behavior of systems within which decisions are made and to estimate the consequences of candidate decisions as scenarios. The experiments are a systematically constructed class of gedanken experiments comparable to "what if' studies, but organized to span the entire space of controllable and uncontrollable options. In any experiment, the quality of data is important. Grounded on the work of scholars, we develop a debiasing process for eliciting data. And consistent with our engineering approach, we consider the composite consisting of the organization, their knowledge, data bases, formal and informal procedures as a measurement system. We then use Gage theory from Measurement Systems Analysis (MSA) to analyze the quality of the measuring composite.; (cont.) To test this engineering approach to decision analysis...

Platforms and real options in large-scale engineering systems

Kalligeros, Konstantinos C., 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 151 p.
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This thesis introduces a framework and two methodologies that enable engineering management teams to assess the value of real options in programs of large-scale, partially standardized systems implemented a few times over the medium term. This enables value creation through the balanced and complementary use of two seemingly competing design paradigms, i.e., standardization and design for flexibility. The flexibility of a platform program is modeled as the developer's ability to choose the optimal extent of standardization between multiple projects at the time later projects are designed, depending on how uncertainty unfolds. Along the lines of previous work, this thesis uses a two-step methodology for valuing this flexibility: screening of efficient standardization strategies for future developments in a program of projects; and valuing the flexibility to develop one of these alternatives. The criterion for screening alternative future standardization strategies is the maximization of measurable standardization effects that do not depend on future uncertainties.; (Cont.) A novel methodology and algorithm, called "Invariant Design Rules" (IDR), is developed for the exploration of alternative standardization opportunities, i.e., collections of components that can be standardized among systems with different functional requirements. A novel valuation process is introduced to value the developer's real options to choose among these strategies later. The methodology is designed to overcome some presumed contributors to the limited appeal of real options theory in engineering. Firstly...