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‣ MASCoT : a model-based automatic software compensation tooklit for feedback systems; Model-based automatic software compensation tooklit for feedback systems

Missiuro, Patrycja Ewelina, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 133 leaves; 867580 bytes; 867341 bytes; application/pdf; application/pdf
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by Patrycja Ewelina Missiuro.; Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.; Includes bibliographical references (leaves 130-133).; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.

‣ Hardware & software architecture for multi-level unmanned autonomous vehicle design; Hardware and software architecture for multi-level UAV design

Davis, Jesse H. Z. (Jesse Harper Zehring), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 131 p.; 6718468 bytes; 6717840 bytes; application/pdf; application/pdf
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by Jesse H.Z. Davis.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.; Includes bibliographical references (p. 95-96).; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.

‣ Design and implementation of software radios using a general purpose processor; Software radios using a general purpose processor

Bose, Vanu G. (Vanu Gopal)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 116 p.; 10393817 bytes; 10393575 bytes; application/pdf; application/pdf
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by Vanu G. Bose.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.; Includes bibliographical references (p. 113-116).

‣ Hive : a software infrastructure for things that think; Software infrastructure for things that think

Roup, Oliver R. (Oliver Richard), 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 71 p.; 5445040 bytes; 5444797 bytes; application/pdf; application/pdf
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by Oliver R. Roup.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.; Includes bibliographical references (p. [65]-68).

‣ Software systems for a DNA sequencer; Software systems for a deoxyribonucleic acid sequencer

Ait-Ghezala, Ahmed, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 49 leaves; 3894075 bytes; 3893834 bytes; application/pdf; application/pdf
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by Ahmed Ait-Ghezala.; Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.; Includes bibliographical references (leaf 49).

‣ Spatial software pipelining on distributed architectures for sparse matrix codes

Duvall, Michelle, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 103 p.; 5290118 bytes; 5302254 bytes; application/pdf; application/pdf
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Wire delays and communication time are forcing processors to become decentralized modules communicating through a fast, scalable interconnect. For scalability, every portion of the processor must be decentralized, including the memory system. Compilers that can take a sequential program as input and parallelize it (including the memory) across the new processors are necessary. Much research has gone towards the ensuing problem of optimal data layout in memory and instruction placement, but the problem is so large that some aspects have yet to be addressed. This thesis presents spatial software pipelining, a new mechanism for doing data layout and instruction placement for loops. Spatial software pipelining places instructions and memory to avoid communication cycles, decreases the dependencies of tiles on each other, allows the bodies of loops to be pipelined across tiles, allows branch conditions to be pipelined along with data, and reduces the execution time of loops across multiple iterations. This thesis additionally presents the algorithms used to effect spatial software pipelining. Results show that spatial software pipelining performs 2.14x better than traditional assignment and scheduling techniques for a sparse matrix benchmark...

‣ VISTA : a visualization tool for computer architects; Visualization tool for computer architects

Mihalik, Aaron D. (Aaron Daniel), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 55 leaves; 3599683 bytes; 3605553 bytes; application/pdf; application/pdf
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As computer architectures continue to grow in complexity, software developers and hardware engineers cope with the increasing complexity by developing proprietary applications, simulations and tool sets to understand the behavior of these complex systems. Although the field of information visualization is leading to powerful applications in many areas, information visualization applications for computer architecture development are either tightly coupled with a specific architecture or target a wide range of computer system data. This thesis introduces the Visualization Tool for Computer Architects (VISTA) Environment. The VISTA Environment is an extensible and modular information visualization environment for hardware engineers, software developers and educators to visualize data from a variety of computer architecture simulations at different levels of abstraction. The VISTA Environment leverages common attributes in simulation data, computer architecture visualizations, and computer architecture development methods to create a powerful information visualization environment to aid in designing, understanding and communicating complex computer architectures.; by Aaron D. Mihalik.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

‣ An extensible software library for developing tactile perception experiments

Meghani, Samir V. (Samir Vijay), 1983-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 53 p.; 2517676 bytes; 2522008 bytes; application/pdf; application/pdf
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A system was designed to reduce the time undergraduate student researchers spend programming while developing tactile perception experiments. The system allows students to program in Matlab, a high-level, interpreted language, and captures functionality common to most experiments in an easily extensible library. To further aid the student, an experiment template that illustrates the structure of a typical experiment is provided. The effectiveness of the system was evaluated by implementing a real-world experiment for measuring the 2-point error of localization of touch on the hand. The experience indicates a decrease in the total programming time and suggests the potential usefulness of interpreters and converters in general software development.; by Samir V. Meghani.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.; Includes bibliographical references (p. 52-53).

‣ Automatic software upgrades for distributed systems

Ajmani, Sameer, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 164 p.; 7066936 bytes; 7087368 bytes; application/pdf; application/pdf
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Upgrading the software of long-lived, highly-available distributed systems is difficult. It is not possible to upgrade all the nodes in a system at once, since some nodes may be unavailable and halting the system for an upgrade is unacceptable. Instead, upgrades may happen gradually, and there may be long periods of time when different nodes are running different software versions and need to communicate using incompatible protocols. We present a methodology and infrastructure that address these challenges and make it possible to upgrade distributed systems automatically while limiting service disruption. Our methodology defines how to enable nodes to interoperate across versions, how to preserve the state of a system across upgrades, and how to schedule an upgrade so as to limit service disrup- tion. The approach is modular: defining an upgrade requires understanding only the new software and the version it replaces. The upgrade infrastructure is a generic platform for distributing and installing software while enabling nodes to interoperate across versions. The infrastructure requires no access to the system source code and is transparent: node software is unaware that different versions even exist. We have implemented a prototype of the infrastructure called Upstart that intercepts socket communication using a dynamically-linked C++ library. Experiments show that Upstart has low overhead and works well for both local-area-and Internet systems.; by Sameer Ajmani.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

‣ Design and implementation of software to automate reuse in component-based system engineering; Software to automate reuse in component-based system engineering

Chan, Chibong
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 62 leaves; 3449977 bytes; 3451780 bytes; application/pdf; application/pdf
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The goal of this thesis is to develop software under the SpecTRM software package for the partial automation of tasks associated with reusing SpecTRM-RL component models. The automation software is designed to aid the application of component-based system engineering in SpecTRM, mainly by reducing the amount of manual work necessary in setting up component models for simulation. My thesis will examine the properties of component models, and the common tasks associated with component-based system engineering, so as to identify areas where automation is possible, and then present the user interfaces and algorithms necessary to achieve automation. The automation software will be implemented in Java under the Eclipse platform, in order to be seamlessly integrated into the SpecTRM software package.; by Chibong Chan.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.; Includes bibliographical references (leaf 45).

‣ A software toolkit for acoustic respiratory analysis

Yi, Gina Ann
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 147 p.; 8625770 bytes; 8631931 bytes; application/pdf; application/pdf
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Millions of Americans suffer from pulmonary diseases. According to recent statistics, approximately 17 million people suffer from asthma, 16.4 million from chronic obstructive pulmonary disease, 12 million from sleep apnea, and 1.3 million from pneumonia - not to mention the prevalence of many other diseases associated with the lungs. Annually, the mortality attributed to pulmonary diseases exceeds 150,000. Clinical signs of most pulmonary diseases include irregular breathing patterns, the presence of abnormal breath sounds such as wheezes and crackles, and the absence of breathing entirely. Throughout the history of medicine, physicians have always listened for such sounds at the chest wall (or over the trachea) during patient examinations to diagnose pulmonary diseases - a procedure also known as auscultation. Recent advancements in computer technology have made it possible to record, store, and digitally process breath sounds for further analysis. Although automated techniques for lung sound analysis have not been widely employed in the medical field, there has been a growing interest among researchers to use technology to understand the subtler characteristics of lung sounds and their potential correlations with physiological conditions. Based on such correlations...

‣ Reducing exception management overhead with software restart markers

Hampton, Mark Jerome, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 196 p.
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Modern processors rely on exception handling mechanisms to detect errors and to implement various features such as virtual memory. However, these mechanisms are typically hardware-intensive because of the need to buffer partially-completed instructions to implement precise exceptions and enforce in-order instruction commit, often leading to issues with performance and energy efficiency. The situation is exacerbated in highly parallel machines with large quantities of programmer-visible state, such as VLIW or vector processors. As architects increasingly rely on parallel architectures to achieve higher performance, the problem of exception handling is becoming critical. In this thesis, I present software restart markers as the foundation of an exception handling mechanism for explicitly parallel architectures. With this model, the compiler is responsible for delimiting regions of idempotent code. If an exception occurs, the operating system will resume execution from the beginning of the region. One advantage of this approach is that instruction results can be committed to architectural state in any order within a region, eliminating the need to buffer those values. Enabling out-of-order commit can substantially reduce the exception management overhead found in precise exception implementations...

‣ Hardware and software for hand-held electrical impedance myography measurement prototype system

Cooper, Roshni C
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 77 p.
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This thesis discusses the need for a more quantitative, objective, and non-invasive method of neuromuscular disease assessment. Currently, the best solution to this problem requires large, bulky pieces of equipment and the time-consuming placement of numerous individual electrodes. In this thesis, a new hardware device and its corresponding software interface are described. The device includes a reconfigurable hand-held probe with an electrode head which both makes contact with the skin and eliminates the need for individual electrodes. The new software interface provides a simple way for users to control the device through the USB interface of a laptop. In addition, various strategies were explored for leveraging the linearity of the muscle tissue in order to shorten the measurement time.; by Roshni C. Cooper.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.; 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. 73-77).

‣ Dr. Jones : a software design explorer's crystal ball; Software design explorer's crystal ball

Foltz, Mark A. (Mark Alan), 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 154 p.
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Most of software design is redesign. Redesign in the normal course of design happens when the software becomes difficult to maintain and the problem it is intended to solve has changed. Although software redesign is necessary, frequent, and pervasive, there is a dearth of tools that help programmers do it. Instead, programmers primarily use pen and paper, away from the computer where tools could help the most. To address this shortcoming, I have developed DR. JONES, a redesign assistant for Java programs. DR. JONES diagrams the class structure of a Java program and allows the programmer to modify that design by applying refactorings. Refactorings are localized patterns of structural change intended to improve a program's design, without changing its observable behavior. With DR. JONES, the programmer can explore the design space of the program, inspect future designs as visual diagrams, and get design assistance to guide his refactoring choices. As the programmer explores designs, DR. JONES explicitly maps the design space he traverses. This map lets him revisit any prior design and branch to explore an alternative design path, without having to explicitly manage versions of the program. DR. JONES is distinguished from other refactoring tools by separating the tasks of developing an improved design through design exploration from transforming the source code to execute design changes. It does so by deriving and using an abstract representation of the program that captures the essential information needed for design exploration...

‣ SoftECC : a system for software memory integrity checking; Soft ECC : a system for software memory integrity checking

Dopson, Dave
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 52 leaves
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SoftECC is software memory integrity checking agent. SoftECC repeatedly computes page-level checksums as an efficient means to verify that a page's contents have not changed. Memory errors that occur between two checksum computations will cause the two checksum values to disagree. Legitimate memory writes also cause a change in checksum value, so a page can only be protected during periods of time when it is not being written to. Preliminary measurements with an implementation of SoftECC in the JOS kernel on the x86 architecture show that SoftECC can halve the number of undetectable soft errors using minimal compute time.; by Dave Dopson.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.; Includes bibliographical references (leaves 51-52).

‣ Software instruction caching

Miller, Jason Eric, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 193 p.
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As microprocessor complexities and costs skyrocket, designers are looking for ways to simplify their designs to reduce costs, improve energy efficiency, or squeeze more computational elements on each chip. This is particularly true for the embedded domain where cost and energy consumption are paramount. Software instruction caches have the potential to provide the required performance while using simpler, more efficient hardware. A software cache consists of a simple array memory (such as a scratchpad) and a software system that is capable of automatically managing that memory as a cache. Software caches have several advantages over traditional hardware caches. Without complex cache-management logic, the processor hardware is cheaper and easier to design, verify and manufacture. The reduced access energy of simple memories can result in a net energy savings if management overhead is kept low. Software caches can also be customized to each individual program's needs, improving performance or eliminating unpredictable timing for real-time embedded applications. The greatest challenge for a software cache is providing good performance using general-purpose instructions for cache management rather than specially-designed hardware. This thesis designs and implements a working system (Flexicache) on an actual embedded processor and uses it to investigate the strengths and weaknesses of software instruction caches. Although both data and instruction caches can be implemented in software...

‣ Automatic testing of software with structurally complex inputs

Marinov, Darko, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 132 p.; 9915845 bytes; 9932926 bytes; application/pdf; application/pdf
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Modern software pervasively uses structurally complex data such as linked data structures. The standard approach to generating test suites for such software, manual generation of the inputs in the suite, is tedious and error-prone. This dissertation proposes a new approach for specifying properties of structurally complex test inputs; presents a technique that automates generation of such inputs; describes the Korat tool that implements this technique for Java; and evaluates the effectiveness of Korat in testing a set of data-structure implementations. Our approach allows the developer to describe the properties of valid test inputs using a familiar implementation language such as Java. Specifically, the user provides an imperative predicate--a piece of code that returns a truth value--that returns true if the input satisfies the required property and false otherwise. Korat implements our technique for solving imperative predicates: given a predicate and a bound on the size of the predicate's inputs, Korat automatically generates the bounded-exhaustive test suite that consists of all inputs, within the given bound, that satisfy the property identified by the predicate. To generate these inputs, Korat systematically searches the bounded input space by executing the predicate on the candidate inputs. Korat does this efficiently by pruning the search based on the predicate's executions and by generating only nonisomorphic inputs. Bounded-exhaustive testing is a methodology for testing the code on all inputs within the given small bound.; (cont.) Our experiments on a set of ten linked and array- based data structures show that Korat can efficiently generate bounded-exhaustive test suites from imperative predicates even for very large input spaces. Further...

‣ Automatic continuous testing to speed software development

Saff, David, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 152 p.; 7410262 bytes; 7410068 bytes; application/pdf; application/pdf
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Continuous testing is a new feature for software development environments that uses excess cycles on a developer's workstation to continuously run regression tests in the background, providing rapid feedback about test failures as source code is edited. It is intended to reduce the time and energy required to keep code well-tested, and to prevent regression errors from persisting uncaught for long periods of time. The longer that regression errors are allowed to linger during development, the more time is wasted debugging and fixing them once they are discovered. By monitoring and measuring software projects, we estimate that the wasted time, consisting of this preventable extra fixing cost added to the time spent running tests and waiting for them to complete, accounts for 10-15% of total development time. We present a model of developer behavior that uses data from past projects to infer developer beliefs and predict behavior in new environments -in particular, when changing testing methodologies or tools to reduce wasted time. This model predicts that continuous testing would reduce wasted time by 92-98%, a substantial improvement over other approaches we evaluated, such as automatic test prioritization and changing manual test frequencies. A controlled human experiment indicates that student developers using continuous testing were three times more likely to complete a task before the deadline than those without...

‣ A distributed embedded software architecture for multiple Unmanned Aerial Vehicles

Matczynski, Michael J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 54 leaves
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In order to deploy intelligent, next-generation applications on Unmanned Aerial Vehicles (UAVs), we must first develop a software architecture that supports onboard computation and flexible communication. This thesis presents an Onboard Planning Module developed from an embedded PC/104 Linux-based computer that communicates directly with the UAV's autopilot to retrieve telemetry data and update the UAV's flight path. A serial communication program exchanges data with the UAV's autopilot while a multithreaded module enables concurrent onboard Mixed-Integer Linear Programming (MILP) optimization. The Mission Manager Graphical User Interface (GUI) monitors the status of each Onboard Planning Module on a team of UAVs using the onboard planning protocol. Two task assignment scenarios are simulated to demonstrate the system operating with both a single and multiple UAV task selection algorithm.; by Michael J. Matczynski.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.; Includes bibliographical references (leaves 52-54).

‣ Motivation, Design, and Ubiquity: A Discussion of Research Ethics and Computer Science

Wright, David R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Modern society is permeated with computers, and the software that controls them can have latent, long-term, and immediate effects that reach far beyond the actual users of these systems. This places researchers in Computer Science and Software Engineering in a critical position of influence and responsibility, more than any other field because computer systems are vital research tools for other disciplines. This essay presents several key ethical concerns and responsibilities relating to research in computing. The goal is to promote awareness and discussion of ethical issues among computer science researchers. A hypothetical case study is provided, along with questions for reflection and discussion.; Comment: Written as central essay for the Computer Science module of the LANGURE model curriculum in Research Ethics