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An aspect-oriented reference architecture for Software Engineering Environments

NAKAGAWA, Elisa Y.; FERRARI, Fabiano C.; SASAKI, Mariela M. F.; MALDONADO, Jose C.
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
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Reusable and evolvable Software Engineering Environments (SEES) are essential to software production and have increasingly become a need. In another perspective, software architectures and reference architectures have played a significant role in determining the success of software systems. In this paper we present a reference architecture for SEEs, named RefASSET, which is based on concepts coming from the aspect-oriented approach. This architecture is specialized to the software testing domain and the development of tools for that domain is discussed. This and other case studies have pointed out that the use of aspects in RefASSET provides a better Separation of Concerns, resulting in reusable and evolvable SEEs. (C) 2011 Elsevier Inc. All rights reserved.; FAPESP; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); CNPq; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); CAPES; European Community[IST-FP6-IP-034763]; European Community

Engenharia de trafego multi-camada para grades; Multi-layer traffic engineering for grid networks

Daniel Macedo Batista
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/06/2006 Português
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Grades são ambientes computacionais caracterizados pela heterogeneidade de recursos e dinamismo. Por serem ambientes dinâmicos, as grades precisam de processos que otimizem a execução das aplicações de forma também dinâmica. Tais processos devem detectar mudanças no estado da grade e tomar medidas para manter o tempo de execução das aplicações o menor possível. Existem diversas propostas de otimização dinâmica de aplicações em grades que visam atender essa necessidade através da migração de tarefas. Esta dissertação propõe uma metodologia que considera variações na disponibilidade dos hosts bem como no estado da rede. A metodologia proposta é baseada nos princípios gerais da engenharia de tráfego e atua em várias camadas da arquitetura Internet. Ela tem como objetivo minimizar o tempo de execução das aplicações e visa ser simples e independente, tanto da aplicação, quanto da grade. Os ganhos obtidos na execução de aplicações em grades com a utilização da proposta, versus a execução sem a mesma, são avaliados através de simulação com exemplos implementados usando o simulador de redes NS-2. Esta dissertação propõe também uma família de escalonadores baseados em programação inteira e em programação mista para o escalonamento de tarefas em grades que modelam o estado dos hosts bem como o da rede...

A unified approach to modeling, verifying, and improving the manufacturability of mechanical assemblies

Gray, J. Michael (John Michael), 1978-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 282 p.; 1663464 bytes; 1663244 bytes; application/pdf; application/pdf
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The goal of a design engineering organization is to design products that satisfy customers. Reaching this objective is dependent, among other things, on five parameters: the customer expectations, the target percentage of satisfied customers, the nominal performance of the design, the variability in the manufacturing processes, and the sensitivity of the design performance to such variability. This work presents a unified methodology that is amendable to computer implementation for modeling these five parameters for products that are primarily mechanical in nature. The validity of this methodology is subject to five major assumptions: the nominal performance of the design matches the performance expected by the customer, the set of customer expectations can be represented completely by a set of geometric relationships and tolerances between features in the assembly, the degradation in product performance is due solely to quantifiable variability or mean shift in the assembly geometry, the variability in each geometric relationship is independent of the variability in any other geometric relationship, and any compliant parts in the assembly can be accurately modeled as sets of rigid parts connected with linearly-compliant joints. The assembly model is developed using a combination of Screw Theory...

Development of the in vivo flow cytometer

Novak, John P. (John Peter), 1957-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 217 leaves; 13480579 bytes; 13508796 bytes; application/pdf; application/pdf
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An in vivo flow cytometer has been developed that allows the real-time detection and quantification of circulating cells containing fluorescent proteins or labeled with fluorochrome molecules in live animals, without the need to extract blood samples. A stationary laser beam is focused by a cylindrical lens to a slit of light that is then demagnified and focused across a blood vessel by an achromat and microscope objective. Fluorescent cells are excited one by one as they flow through the excitation laser light slit, creating a burst of fluorescence whose width is inversely proportional to their velocity. The fluorescence signal is detected through a confocal slit aperture using a photomultiplier tube. The analog signal from the photomultiplier tube is then digitized, filtered, and recorded as a function of time onto a computer. Computer programs post- process the data for the presence of cell signal, as well as various aspects of the cell signal such as height, width, and temporal location of the signal peak. Two in vivo flow cytometers have been built: a single-slit, single-color system and a two- slit, two-color system. The single-slit, single-color system provides excitation at 632 nm, and the two-slit, two-color system provides excitation at 632 nm and 473 nm. The two- slit...

Estimation method for the thermochemical properties of polycyclic aromatic molecules

Yu, Joanna
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 384 p.; 17728388 bytes; 17745329 bytes; application/pdf; application/pdf
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Polycyclic aromatic molecules, including polycyclic aromatic hydrocarbons (PAHs) have attracted considerable attention in the past few decades. They are formed during the incomplete combustion of hydrocarbon fuels and are precursors of soot. Some PAHs are known carcinogens, and control of their emissions is an important issue. These molecules are found in many materials, including coal, fuel oils, lubricants, and carbon black. They are also implicated in the formation of fullerenes, one of the most. chemically versatile class of molecules known. Clearly, models that provide predictive capability for their formation and growth are highly desirable. Thlermochemical properties of the species in the model are often the most important parameter, particularly for high temperature processes such as the formation of PAH and other aromatic molecules. Thermodynamic consistency requires that reverse rate constants be calculated from the forward rate constants and from the equilibrium constants. The later are obtained from the thermochemical properties of reactants and products. The predictive ability of current kinetic models is significantly limited by the scarcity of available thermochemical data.; (cont.) In this work we present the development of a Bond-Centered Group Additivity method for the estimation of the thermochemical properties of polycyclic aromatic molecules...

Modeling security and cooperation in wireless networks using game theory

Kamhoua, Charles Alexandre Kenmogne
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
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This research involves the design, development, and theoretical demonstration of models resulting in integrated misbehavior resolution protocols for ad hoc networked devices. Game theory was used to analyze strategic interaction among independent devices with conflicting interests. Packet forwarding at the routing layer of autonomous ad hoc networks was investigated. Unlike existing reputation based or payment schemes, this model is based on repeated interactions. To enforce cooperation, a community enforcement mechanism was used, whereby selfish nodes that drop packets were punished not only by the victim, but also by all nodes in the network. Then, a stochastic packet forwarding game strategy was introduced. Our solution relaxed the uniform traffic demand that was pervasive in other works. To address the concerns of imperfect private monitoring in resource aware ad hoc networks, a belief-free equilibrium scheme was developed that reduces the impact of noise in cooperation. This scheme also eliminated the need to infer the private history of other nodes. Moreover, it simplified the computation of an optimal strategy. The belief-free approach reduced the node overhead and was easily tractable. Hence it made the system operation feasible. Motivated by the versatile nature of evolutionary game theory...

Naval ship concept design for the Republic of Korea Navy a systems engineering approach

Choi, Hanwool
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xiv, 63 p. : col. ill.
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Approved for public release, distribution unlimited; This thesis presents a new systems engineering based approach to naval ship concept design for the Republic of Korea (R.O.K.) Navy. The R.O.K. Navy currently uses a traditional naval architecture approach in concept design. Naval architects focus only on naval architecture issues such as speed, range, and displacement; combat systems engineers focus on the performance of combat systems, weapons, and sensors. This design process creates some integration problems in the late design stage and during construction. For this reason, there is a growing interest in the systems engineering approach design concept in the R.O.K. Navy. Naval ship design is an aggregate of engineering, computer science, management, and even strategy and policy. Naval ship engineers should consider not only naval architecture issues such as hull form, stability, structure, maneuverability and propulsion, but also mission needs, effectiveness, cost/risk benefits, and integration with all combat systems. Naval architecture and combat systems engineering are a part of the design process, and they must be considered simultaneously a systems engineering approach to combatant ship design. To properly design a naval ship...

The fate of phosphonate inhibitors in oil and gas reservoirs: Validation of the SqueezeSoft(TM) computer program

Watson, Malene Abena
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: 166 p.; application/pdf
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The deposition of material that has precipitated out of solution can cause problems that plague a variety of engineering and biological processes. Scale formation in cooling towers, boilers, and oil/gas operations are prevented with chemical inhibitors such as nitrilotris (methylene phosphonic acid). The release of this phosphonate from solid material is studied with batch and dynamic flow experiments. The corresponding observations can be incorporated into SqueezeSoft(TM), a computer program, written by the Rice University Brine Chemistry Consortium. This work attempts to examine SqueezeSoft(TM)'s ability to identify the placement of inhibitor during a squeeze treatment and the corresponding reactions that occur. SqueezeSoft(TM) has been found to correctly predict the profile of inhibitor injected into a column packed with core material. Because this program is based on theory and not on empirical findings, it can be expanded to other more general applications.

A very big adventure: using the internet to enable multi-institutional collaboration in teaching computer ethics

Griffin, Joe
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/conferenceObject; all_ul_research
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non-peer-reviewed; Teaching and learning in any subject can sometimes become mundane but in order that our students are motivated it is sometimes necessary to use an approach which makes the process a very big adventure. Over the past three years studies have taken place with students from the University of Limerick in Ireland and students from two other universities in England and the USA in the teaching of Professional Issues in Software Engineering PISE (Griffin, 2001, Griffin et al 2000a and 2000b). PISE focuses on the legal, ethical and social aspects of computing. The ethical strand of this module, which aims to develop moral reasoning in the learners, has in the author's experience often proved to be the most difficult for students to grasp and consequently has had a de-motivating effect on some learners. To deal with this situation the author decided to investigate methods by which students might be motivated and therefore gain more from their learning experiences and develop their moral reasoning abilities. The method adopted has been the use of virtual learning groups using internet based asynchronous communication tools to enable learners who would otherwise physically be unable to meet to come together in cyberspace and discuss moral issues relating to computer systems. This paper describes two cycles of the study...

Distributed & conceptual CAD (DC-CAD) : a new software solution for product design; DC-CAD : a new software solution for product design

Egan, Mark D. (Mark Douglas), 1985-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 34 p.
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Many computer aided design (CAD) software packages focus on detailed design and not on early stage, conceptual design. The ability to conceptualize and sketch early versions of a product solution is currently limited to paper and pencil or to inadequate computer-aided industrial design programs (CAID) that focus mainly on surface design, not product design. Working on a design as a group also poses problems since the team can be geographically distributed. In an attempt to address the current inadequacies of CAD systems for distributed conceptual design, my thesis proposes a vision for a new CAD program, DC-CAD. This vision anticipates network-orientated conceptual design, and encompasses capabilities for multiple users to collaborate simultaneously on design, compare & evaluate concept sketches, comment on designs and merge changes from other designers, transfer data to detailed design CAD programs, and record concept changes over time. MIT's Product Engineering Class (2.009) was used as the basis for conceiving the software system. By analyzing design challenges that arose during the course, new software features are suggested to mitigate such problems.; (cont.) The end result is a clear vision for a new program, DC-CAD, and a storyboard example of how it could be used in a futuristic 2.009 setting. The thesis closes with recommendations on how to pursue the implementation and realization of such a CAD system.; by Mark D. Egan.; Thesis (S.B.)--Massachusetts Institute of Technology...

A Survey of Reverse Engineering and Program Comprehension

Nelson, Michael L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/03/2005 Português
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Reverse engineering has been a standard practice in the hardware community for some time. It has only been within the last ten years that reverse engineering, or "program comprehension", has grown into the current sub-discipline of software engineering. Traditional software engineering is primarily focused on the development and design of new software. However, most programmers work on software that other people have designed and developed. Up to 50% of a software maintainers time can be spent determining the intent of source code. The growing demand to reevaluate and reimplement legacy software systems, brought on by the proliferation of clientserver and World Wide Web technologies, has underscored the need for reverse engineering tools and techniques. This paper introduces the terminology of reverse engineering and gives some of the obstacles that make reverse engineering difficult. Although reverse engineering remains heavily dependent on the human component, a number of automated tools are presented that aid the reverse engineer.; Comment: originally released as web-only in 1996

A Novel Window Function Yielding Suppressed Mainlobe Width and Minimum Sidelobe Peak

Samad, Md Abdus
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/05/2012 Português
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In many applications like FIR filters, FFT, signal processing and measurements, we are required (~45 dB) or less side lobes amplitudes. However, the problem is usual window based FIR filter design lies in its side lobes amplitudes that are higher than the requirement of application. We propose a window function, which has better performance like narrower main lobe width, minimum side lobe peak compared to the several commonly used windows. The proposed window has slightly larger main lobe width of the commonly used Hamming window, while featuring 6.2\ sim 22.62 dB smaller side lobe peak. The proposed window maintains its maximum side lobe peak about -58.4 \sim -52.6 dB compared to -35.8 \sim -38.8 dB of Hamming window for M=10~14, while offering roughly equal main lobe width. Our simulated results also show significant performance upgrading of the proposed window compared to the Kaiser, Gaussian, and Lanczos windows. The proposed window also shows better performance than Dolph-Chebyshev window. Finally, the example of designed low pass FIR filter confirms the efficiency of the proposed window.; Comment: 13 pages, 10 figures, AIRCC (International Journal of Computer Science, Engineering and Information Technology(IJCSEIT), Md Abdus Samad...

Seeking the Principles of Sustainable Software Engineering

Shi, Justin
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Like other engineering disciplines, software engineering should also have principles to guide the construction of sustainable computer applications. Tangible properties include a) unlimited scalability, b) maximal reproducibility, and c) optimizable energy efficiency. In practice, we expect a sustainable scientific application should be written once and execute many times on multiple different processing platforms of different scales with optimized performance and energy efficiency. For more than two decades, explicit parallel programming/processing paradigms only focused on performance. Practices showed that the rigid program-data binding prohibited dynamic runtime resource optimization and fault isolation, making it difficult to reproduce applications in scale. This paper reports our practice and experiences in search of the first principles of sustainable software engineering for compute and data intensive applications. Specifically, we report our practice and experiences using implicit parallel programming/processing paradigms.; Comment: WSSSPE 2014

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
Publicado em 04/06/2007 Português
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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

Psychological Types of Brazilian Software Engineering Students

Capretz, Luiz Fernando
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/11/2015 Português
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The aim of this investigation was to establish the personality profile of Brazilian software engineering students according to the MBTI. This study also shows that the software engineering field attracts students of some types more than other types, for instance: Is, Ps, IPs, TPs, and INs are significantly represented in that group as opposed to E, Js, EJs, TJs, ENs.; Comment: arXiv admin note: text overlap with arXiv:1507.06873

Multi-representation d'une ontologie : OWL, bases de donnees, syst\`emes de types et d'objets

Arnoux, Mireille; Despeyroux, Thierry
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/04/2011 Português
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Due to the emergence of the semantic Web and the increasing need to formalize human knowledge, ontologie engineering is now an important activity. But is this activity very different from other ones like software engineering, for example ? In this paper, we investigate analogies between ontologies on one hand, types, objects and data bases on the other one, taking into account the notion of evolution of an ontology. We represent a unique ontology using different paradigms, and observe that the distance between these different concepts is small. We deduce from this constatation that ontologies and more specifically ontology description languages can take advantage of beeing fertilizated with some other computer science domains and inherit important characteristics as modularity, for example.; Comment: ISBN: 978-1-60558-842-1

Computational Simulation and 3D Virtual Reality Engineering Tools for Dynamical Modeling and Imaging of Composite Nanomaterials

Bochkareva, L. -V.; Kireitseu, M. -V.; Tomlinson, G. R.; Altenbach, H.; Kompis, V.; Hui, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/08/2007 Português
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An adventure at engineering design and modeling is possible with a Virtual Reality Environment (VRE) that uses multiple computer-generated media to let a user experience situations that are temporally and spatially prohibiting. In this paper, an approach to developing some advanced architecture and modeling tools is presented to allow multiple frameworks work together while being shielded from the application program. This architecture is being developed in a framework of workbench interactive tools for next generation nanoparticle-reinforced damping/dynamic systems. Through the use of system, an engineer/programmer can respectively concentrate on tailoring an engineering design concept of novel system and the application software design while using existing databases/software outputs.; Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions)

What we should teach, but don't: Proposal for a cross pollinated HCI-SE curriculum

Pyla, Pardha S.; Perez-Quinones, Manuel A.; Arthur, James D.; Hartson, H. Rex
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/03/2004 Português
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Software engineering (SE) and usability engineering (UE), as disciplines, have reached substantial levels of maturity. Each of these two disciplines is now well represented with respect to most computer science (CS) curricula. But, the two disciplines are practiced almost independently - missing oppurtunities to collaborate, coordinate and communicate about the overall design - and thereby contributing to system failures. Today, a confluence of several ingredients contribute to these failures: the increasing importance of the user interface (UI) component in the overall system, the independent maturation of the human computer interaction area, and the lack of a cohesive process model to integrate the UI experts' UE development efforts with that of SE. This in turn, we believe, is a result of a void in computing curricula: a lack of education and training regarding the importance of communication, collaboration and coordination between the SE and UE processes. In this paper we describe the current approach to teaching SE and UE and its shortcomings. We identify and analyze the barriers and issues involved in developing systems having substantial interactive components. We then propose four major themes of learning for a comprehensive computing curriculum integrating SE...

Fuzzy Model on Human Emotions Recognition

Bakhtiyari, Kaveh; Husain, Hafizah
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/07/2014 Português
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This paper discusses a fuzzy model for multi-level human emotions recognition by computer systems through keyboard keystrokes, mouse and touchscreen interactions. This model can also be used to detect the other possible emotions at the time of recognition. Accuracy measurements of human emotions by the fuzzy model are discussed through two methods; the first is accuracy analysis and the second is false positive rate analysis. This fuzzy model detects more emotions, but on the other hand, for some of emotions, a lower accuracy was obtained with the comparison with the non-fuzzy human emotions detection methods. This system was trained and tested by Support Vector Machine (SVM) to recognize the users' emotions. Overall, this model represents a closer similarity between human brain detection of emotions and computer systems.; Comment: 12th WSEAS International Conference on Applications of Computer Engineering (ACE '13), Cambridge, MA, USA, 30 Jan. - 1 Feb. 2013 ISBN: 978-1-61804-156-2, Pages 77-82

A Paradigm for Spreadsheet Engineering Methodologies

Grossman, Thomas A.; Ozluk, Ozgur
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/02/2008 Português
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Spreadsheet engineering methodologies are diverse and sometimes contradictory. It is difficult for spreadsheet developers to identify a spreadsheet engineering methodology that is appropriate for their class of spreadsheet, with its unique combination of goals, type of problem, and available time and resources. There is a lack of well-organized, proven methodologies with known costs and benefits for well-defined spreadsheet classes. It is difficult to compare and critically evaluate methodologies. We present a paradigm for organizing and interpreting spreadsheet engineering recommendations. It systematically addresses the myriad choices made when developing a spreadsheet, and explicitly considers resource constraints and other development parameters. This paradigm provides a framework for evaluation, comparison, and selection of methodologies, and a list of essential elements for developers or codifiers of new methodologies. This paradigm identifies gaps in our knowledge that merit further research.; Comment: 11 Pages