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Signals in Communication Engineering History

Consonni, Denise; Silva, Magno Teófilo Madeira da
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
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This paper is a study of various electric signals, which have been employed throughout the history of communication engineering in its two main landmarks: the telegraph and the telephone. The signals are presented in their time and frequency domain representations. The historical order has been followed in the presentation: wired systems, spark gap wireless, continuous wave (CW) and amplitude modulation (AM), detection by rectification, and frequency modulation (FM). The analysis of these signals is meant to lead into a better understanding of the evolution of communication technology. The material presented in this work could be used to illustrate ""Signals and Systems"" and ""Communication Systems"" courses by taking advantage of its technical as well as historical contents.; FAPESP[2008/00773-1]; CNPq[302633/2008-1]; Escola Politecnica, University of Sao Paulo (USP), Sao Paulo, Brazil

Application of new methodologies in an industrial electronics engineering course : case study

Leão, Celina Pinto; Oliveira, Filomena
Fonte: iNEER Publicador: iNEER
Tipo: Conferência ou Objeto de Conferência
Publicado em //2006 Português
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This paper describes an experience of ‘blended learning solution’ in different areas of an engineering course at a Portuguese University. This arose from the current interest in innovation and the new trends in engineering education. The communication between teacher and student is becoming increasingly important in students’ learning process. The Internet makes this communication possible and web tools, such as multimedia and video, makes it a practical:proposition: when the personal contact is not feasble the Internet enables contact through e-mail and web tools, as animations, motivate students to study. The solution described is a mix of traditional learning practices and e-learning, a blended approach that was implemented in the Industrial Electronics Engineering graduated course at the University of Minho. Three subjects were selected: Numerical Methods (3rd year), Automation (4th year) and Process Control (4th year). Due to the characteristics of numerical methods subject, problems are usually solved by using computers and, as this new methodology computer-based, students readily adapt and are naturally motivated. Using the knowledge acquired by this experience with numerical methods, the same methodology was applied to Automation and Process Control. Along with web tools and Internet services used for information retrieval and learning repository...

Development of a process for the production of fluxless solder spheres for BGA electronics packaging; Development of a process for the production of fluxless solder spheres for ball grid array electronics packaging

Rocha Alvarez, Juan Carlos, 1971-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 86 leaves; 5122068 bytes; 5121874 bytes; application/pdf; application/pdf
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by Juan Carlos Rocha Alvarez.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.; Includes bibliographical references (leaves 84-86).

Printed electronics and micro-electromechanical systems; Printed electronics and MEMS systems

Wilhelm, Eric Jamesson, 1977-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 121 p.; 7170783 bytes; 7170783 bytes; application/pdf; application/pdf
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Current electronics and micro-electromechanical systems (MEMS) manufacture is optimized for the production of very high-volume parts on a limited range of substrates. These processes are long, consume large amounts of resources, and require expensive machines and facilities, but yield excellent products. Cheaper, faster printing processes are beginning to emerge with the ability to economically produce low or high-volume electronics and MEMS on flexible substrates. This thesis describes the theoretical and practical design of a suite of printing processes including liquid embossing and offset liquid embossing (OLE). These printing techniques have created resistors, capacitors, and thin-film transistors without etching, vacuum deposition, or high temperatures. Here, the fabrication of all-printed electrostatic actuators is described In liquid embossing a polydimethylsiloxane (PDMS) stamp with bas-relief features is brought into intimate contact with a thin liquid film such as a metal or semi-conductor nanoparticle colloid, spin-on-glass, or polymer to create patterns as small as 100 nm. A simulation of liquid embossing was developed by coupling fluid flow in a thin liquid film to the diffusion of solvent into a PDMS stamp. The model accurately predicts real aspects of the printing process including the time required to stamp and usable stamp geometries. OLE was designed to address some of the limitations of liquid embossing. In OLE the patterned liquid film is transferred to a different substrate...

Control of the UDS process for the production of solder balls for BGA electronics packaging; Control of the Uniform Droplet Spray process for the production of solder balls for Ball Grid Array electronics packaging

Rocha Alvarez, Juan Carlos, 1971-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 79 leaves; 4450367 bytes; 4458764 bytes; application/pdf; application/pdf
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by Juan Carlos Rocha Alvarez.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1997.; Includes bibliographical references (leaves 78-79).

Operational sustainability metrics : a case of electronics recycling

Atlee, Jennifer Robinson
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 127 p.; 10729810 bytes; 10736001 bytes; application/pdf; application/pdf
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In the past 15 years corporations and governments have developed a growing appreciation of the need for "sustainability" and have worked the term into their goals, strategy and mission statements. Despite extensive efforts to define the term, there is still little clarity on how to move toward sustainability or measure improvements. Further advances toward sustainability will require system specific metrics to assess both current performance and the impact of operational, technological or regulatory changes on that performance. Not only are there currently few operational metrics by which to practically assess progress toward sustainability, there is also very little understanding of how to judge the effectiveness of such metrics. Electronics recycling is used in this thesis as a case problem in developing and evaluating system specific performance metrics for sustainability. Electronics recycling is a growing national and international concern due to the increasing volume of waste, the potential toxicity of the scrap, and reports of improper handling and disposal. Despite this concern, there is limited understanding about the electronics recycling system. There is a need for systematic ways to describe system functioning and quantitative methods to assess system performance. Existing evaluations of eco-efficiency or sustainability are either too aggregated to guide operational decisions or too complex and data intensive to be performed in the context of a low-margin system. A range of performance metrics were developed and assessed for several electronics recycling operators. These included measures of resource recovery and environmental performance.; (cont.) These metrics were assessed for their ability to provide insights on resource efficiency comparable to more complex indicators...

Free air breathing planar PEM fuel cell design for portable electronics

Crumlin, Ethan J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 33 leaves; 1707743 bytes; 1706797 bytes; application/pdf; application/pdf
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PEM fuel cell technology is an energy source that can provide several times more energy per unit volume then current lithium ion batteries. However, PEM fuel cells remain to be optimized in volume and mass to create a minimum size for integration into portable electronics. A planar fuel cell design utilizes the bare minimum in volume and mass over current stacked fuel cell designs. This was done by taking an innovative approach of assembling the fuel cell with just the bare minimum components, a proton exchange membrane, cathode electrode, anode electrode, and gas diffusion layer on both sides of the membrane to assume the role of GDL and current collector. This planar fuel cell design was able to produce a power density over 25mW/cm2. This is an order of magnitude lower then reported air breathing fuel cell values, however the route cause has been isolated to the ohmic losses of the planar fuel cell. Increasing the applied contact forces and creating low resistance electronically conductive grid lines, have shown to contribute to the reduction in ohmic resistance and will be the focus of future research. From this research, a planar fuel cell design has been shown to successful work and there are ways to improve its performance.; by Ethan J. Crumlin.; Thesis (S.B.)--Massachusetts Institute of Technology...

Courseware development for a laboratory class in power electronics

Alvira, Mariano
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 103 leaves; 4675638 bytes; 4679907 bytes; application/pdf; application/pdf
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This thesis introduces a new lab kit that is uniquely suited to teach power electronics: the Power NerdKit. The Power NerdKit is a self-contained prototyping system, which is easily incorporated into other systems such as an electric go-kart. Central to the kit is the card-rack prototyping area, where circuitry on PCB cards can be installed, interconnected, and tested. We present three prototyping PCB cards for use with the kit. Each of the cards has a common interconnection inter- face: up to five high current connections can be made via terminal lugs, and up to 26 low current connections can be made via card-edge connector. The first card provides solderless breadboard for constructing circuits and can connect with other cards through the standard interface. The second card is similar to the first, but is designed for circuits that must be soldered together. The last card, called the TriTotemII, implements three "totem-pole" circuits, which form the foundation of the converter topologies taught in the class. Finally the cards feature a unique method to attach oddly shaped devices using Unplated Through-hole Anchor Points. The lab exercises emphasize design.; (cont.) In Lab 1, the student: learns why switching circuits are useful; learns a few necessary control circuits; and builds a switching audio amplifier. In Lab 2...

Development of three-dimensional passive components for power electronics; Development of 3D passive components for power electronics

Cantillon-Murphy, Pádraig J
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 88 leaves; 3793176 bytes; 3796792 bytes; application/pdf; application/pdf
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As component and power densities have increased, printed circuit boards (PCBs) have taken on additional functionality including heatsinking and forming constituent parts of electrical components. PCBs are not well suited to these tasks. A novel fabrication method is proposed to develop an enhanced circuit board fabrication approach which overcomes this problem. This method uses a photoresistive scaffold and subsequent metallization to realize the proposed structures. These structures are suitable as heatsinks, inductor windings, busbars and EMI shields among other applications.; by Pádraig J. Cantillon-Murphy.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.; Includes bibliographical references (leaves 85-88).

Multi-layer three-dimensional silicon electronics enabled by wafer bonding; Multi-layer 3D silicon electronics enabled by wafer bonding

Tan, Chuan Seng, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 179 p.
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Three-dimensional integrated circuits (3-D ICs), in the form of a vertical stack of several interconnected device layers, have many performance, form factor, and integration advantages. The main objective of this work is to develop reliable process technology to enable the fabrication of a vertically interconnected silicon multi-layer stack. Low temperature wafer bonding processes, both copper thermo-compression bonding and silicon dioxide fusion bonding, are studied extensively as key enabling technology. Cu thermo-compression bonding is studied for its feasibility as a permanent bond between active layers in a multi-layer stack. It is found that pre-bonding anneal in forming gas can remove surface oxide on Cu wafers and reduce the oxygen content in the bonded layer. The quality of bonded Cu layer is adversely degraded by the formation of interfacial voids. Void nucleation and growth are studied and counter-measures for void suppression are proposed and implemented. Silicon dioxide wafer bonding, on the other hand, is used as a temporary bond to attach a donor wafer to a handle wafer during donor wafer thinning and subsequent layer transfer. Sufficiently high bond strength is obtained with careful surface preparation and activation prior to bonding.; (cont.) Silicon layer can be stacked either in a "face down" or "face up" orientation. Using a combination of wafer bonding and thinning...

ELVIS iLab : a flexible platform for online laboratory experiments in electrical engineering; Flexible platform for online laboratory experiments in electrical engineering

Gikandi, Samuel
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 83 leaves
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This thesis describes a project that is part of the collaboration between MIT and universities in sub-Sahara Africa to exploit the value of iLabs in the developing world. The main goal of this project is to develop software that will exploit the value of the National Instruments Educational Laboratory Virtual Instrumentation Suite (ELVIS) system in Africa by integrating it into the iLabs shared architecture, while taking into consideration the special circumstances surrounding the deployment of iLabs in Africa such as bandwidth limitations, limited access to networked computers and lack of computer skills on the part of students. Integrating ELVIS into iLabs will facilitate the rapid deployment of new online labs to augment the Physics and Electrical engineering curricula in these universities. iLab development efforts for this project are being done in parallel with developers at the Obafemi Awolowo University (OAU) in Nigeria. One of the main goals of the new system is to fill the gap of laboratory experiences in introductory level electronics and physics classes, which are hardest hit by the lack of equipment due to their typically large enrollment. Our goal is to support the development of electronic circuit building skills by providing an environment where students can easily try different circuit configurations before submitting experiments for execution. We are therefore investigating new iLab client user interface designs that will enable students to create and edit circuit schematics from provided electronic components. Our ELVIS iLab design will also formalize and simplify the process of creating and administering such labs for instructors...

Reverse logistics and large-scale material recovery from electronics waste

Krones, Jonathan Seth
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 111 p.
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Waste consolidation is a crucial step in the development of cost-effective, nation-wide material reclamation networks. This thesis project investigates typical and conformational tendencies of a hypothetical end-of-life electronics recycling system based in the United States. Optimal waste processor configurations, along with cost drivers and sensitivities are identified using a simple reverse logistics linear programming model. The experimental procedure entails varying the model scenario based on: type of material being recycled, the properties of current recycling and consolidation practices, and an extrapolation of current trends into the future. The transition from a decentralized to a centralized recycling network is shown to be dependent on the balance between transportation costs and facility costs, with the latter being a much more important cost consideration than the former. Additionally, this project sets the stage for a great deal of future work to ensure the profitability of domestic e-waste recycling systems.; by Jonathan Seth Krones.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.; Includes bibliographical references (p. 107-111).

Modular development of an educational remote laboratory platform for electrical engineering : the ELVIS iLab; ELVIS iLab

Jiwaji, Adnaan
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 76 p.
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iLabs are remote online laboratories that allow users to perform experiments through the Internet. As an educational tool the iLab platform enables students and educators, who do not have access to laboratories, to complement their theoretical knowledge by carrying out experiments remotely on equipment located anywhere in the world and at any time of the day. Students perform experiments on actual instruments allowing them to get real data, instead of relying on simulations. The iLab project has been deployed in 3 universities in Africa using the National Instruments Educational Laboratory Virtual Instrument Suite platform which is a cheap all-in-one electronics workstation for electronics experiments. This thesis describes an increase in the functionality available on the current version of the ELVIS iLab in order to enable a wider range of experiments to be run on the platform. The functionalities explored include adding two arbitrary waveform generator channels and bode analyzer for frequency domain analysis, which was not possible in the previous designs.; by Adnaan Jiwaji.; 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. 75-76).

List of Graduates of Engineering Electronics Course since 1914, by Class

Fonte: Monterey, California, Naval Postgraduate School Publicador: Monterey, California, Naval Postgraduate School
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A roster of electronics engineering alumni. The attached PDF provides that list from 1914-1963. Several notable graduates include E.H. Loftin, who was a pioneer in the early development of radio communications for naval aviation; Joseph Weber, who developed the first gravitational wave detectors; and Argentine LCDR Oswaldo Repetto, who may have been the first international officer to attend NPS; and Jerry Tuttle, who played a key role in the development of computing and electronic warfare. Compiled January 1956, Revised December 1958.

Pilotless aircraft telemetry

Knight, Francis Samuel
Fonte: Annapolis, Maryland: Naval Postgraduate School Publicador: Annapolis, Maryland: Naval Postgraduate School
Tipo: Tese de Doutorado Formato: iv, 72 p. iv, 72 p.
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The purpose of this paper is to provide a fundamental introduction to the process of telemetering. Although the subject of the paper is limited to pilotless aircraft and guided missile applications, the limitation is not a great one because it is this field which has produced most of the telemetering techniques now in use. It is hoped that a study of the following pages will enable the reader to better understand and evaluate any particular telemetering system he may encounter. The paper was written in the main part during the third year of the electronics engineering curriculum at the U. S. Naval Postgraduate School. Much information and experience useful in the writing .of the paper was gained during the writer's eleven-week working visit in the Electronics Department of the Glenn L. Martin Company at Middle River, Maryland.; Lieutenant Commander, United States Navy

Virtual prototype simulation case study in mechatronic product development based on systems engineering approach

Carvajal Arango, Ricardo; Mej??a Guti??rrez, Ricardo
Fonte: Grupo de Investigaci??n en Ingenier??a de Dise??o - GRID; Design Engineering Research Group - GRID; Escuela de Ingenier??a Publicador: Grupo de Investigaci??n en Ingenier??a de Dise??o - GRID; Design Engineering Research Group - GRID; Escuela de Ingenier??a
Tipo: conferenceObject; Documento de conferencia; publishedVersion
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Nowadays consumers are demanding products richer in technologies and associated services -- That is why the link between disciplines, such as Engineering Design and Mechatronics, gets stronger each day, especially, due to the different functionalities and features that should be integrated in products in a more articulated manner -- In order to prepare the future generation of engineers, they should be aware and must know the supporting tools recently available in the market to support and automate these interactions among disciplines -- Regular engineering design approaches, start from requirements understanding and end with a physical prototype, passing by conceptual and detailed design -- Nevertheless, the product design process should allow engineering students to forecast product behaviour and its validation through simulation in early design phases, before physical prototyping -- In some cases, complexity increases as products require the integration of technical systems involving mechanics, electronics and control, among others -- Therefore, design concepts cannot be easily tested using a traditional CAD package that needs a physical prototype for validation purposes -- This article presents a case study using a Systems Engineering approach in academia (with RFLP Requirements/Functions/Logical/Physical) to develop a virtual prototype of a mechatronic product...

Magnetic machines and power electronics for power MEMS applications

Das, Sauparna, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 323 p.; 16921694 bytes; 16936400 bytes; application/pdf; application/pdf
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This thesis presents the modeling, design, and characterization of microfabricated, surface-wound, permanent-magnet (PM) generators, and their power electronics, for use in Watt-level Power MEMS applications such as a microscale gas turbine engine. The generators are three-phase, axial-flux, synchronous machines, comprising a rotor with an annular PM and ferromagnetic core, and a stator with multi-turn surface windings on a soft magnetic substrate. The fabrication of the PM generators, as well as the development of their high-speed spinning rotor test stand, was carried out by collaborators at the Georgia Institute of Technology. The machines are modeled by analytically solving 2D magneto-quasistatic Maxwell's Equations as a function of radius and then integrating the field solutions over the radial span of the machine to determine the open-circuit voltage, torque and losses in the stator core. The model provides a computationally fast method to determine power and efficiency of an axial-air-gap PM machine as a function of geometry, speed and material properties. Both passive and active power electronics have been built and tested. The passive power electronics consist of a three-phase transformer and diode bridge rectifier.; (cont.) The active power electronics consist of a switch-mode rectifier based on the boost semi-bridge topology which is used to convert the unregulated AC generator voltages to a regulated 12 V DC without the need for rotor position/speed or stator terminal current/voltage sensing. At the rotational speed of 300...

Achieving competence-based curriculum in Engineering Education in Spain

Edwards Schachter, Mónica E.; Sánchez Ruiz, Luis Manuel; Sánchez Díaz, C.
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: Artículo Formato: 1728561 bytes; application/pdf
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5 tables, 5 figures, 10 pages; The fact of placing competences and outcomes learning at the heart of the academic activity means overhauling the curricular architecture of higher education in Europe. Some universities have undergone important transformations moving toward a competence-based learning environment, while others maintain traditional curriculum packaged formats. In the realm of the European Higher Education Area, this paper examines the use of competence-based initiatives in curricular development for engineering degrees with special focus to the Spanish case. Although the concept of competence and competence-based learning has a long history in education and training research, these terms are still very diffuse and demand a clear conceptualization. In the first part of this paper, we provide a conceptual overview and a critical reflection of competences as implemented in a wide range of settings, including its origins, key concepts, and definitions. Next, we discuss the purposes, principles, pitfalls, and processes that enable defining a map of competences within engineering education. Lastly, we present a pilot project involving curriculum development and faculty enhancement within a competence-based learning initiative in Electronic Engineering.; This work was supported in part by the Program of European Convergence (Universidad Politécnica de Valencia) and developed within the Project of Adaptation to the European Higher Education in the School of Design Engineering.; Peer reviewed

Engineering students' perceptions of innovation and entrepreneurship competences

Edwards Schachter, Mónica E.; Sánchez Ruiz, Luis Manuel; Tovar Caro, E.; Ballester Sarrias, E.
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: Comunicación de congreso Formato: 66946 bytes; application/pdf
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Trabajo presentado a la 39th ASEE/IEEE Frontiers in Education Conference (FIE'09): "Imaging and engineering future CSET education" celebrada en San Antonio (Texas, US) del 18 al 21 Octubre de 2009.; In this paper we present the results of exploring students’ ideas about innovation and entrepreneurship concepts and the way that they perceive that innovation and entrepreneurship competences are developed or improved by engineering education. Comparisons are made between two samples (N= 119 students) at the School of Design Engineering (Polytechnic University of Valencia) by using a questionnaire-based methodology. The results show that the majority of students reported not receiving enough training in innovation and entrepreneurship competences. Thus a greater attention is to be paid to embed innovation and entrepreneurship competences into the current curricular reform in engineering education in Spain having in mind that an innovative and enterprise culture are vital to promote growth and development, increase productivity, create jobs and reinforce the knowledge based economy in Europe.; Peer reviewed

SE2004: Recommendations for undergraduate software engineering curricula

Diaz-Herrera, Jorge; Hilburn, Thomas; LeBlanc, Richard Jr.; Lethbridge, Timothy; Sobel, Ann
Fonte: Institute of Electrical and Electronics Engneers (IEEE) Publicador: Institute of Electrical and Electronics Engneers (IEEE)
Tipo: Artigo de Revista Científica
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Universities throughout the world have established undergraduate programs in software engineering, which complement existing programs in computer science and computer engineering. To provide guidance in designing an effective curriculum, the IEEE Computer Society and the ACM have developed the Software Engineering 2004 (SE2004) set of recommendations. The SE2004 document guides universities and colleges regarding the knowledge they should teach in undergraduate software engineering programs. It also provides sample courses and curriculum patterns. SE2004 begins with an overview of software engineering, explaining how it is both a computing and an engineering discipline. It then outlines the principles that drove the document's development and describes expected student outcomes. Next, SE2004 details the knowledge that universities and colleges should teach, known as SEEK (software engineering education knowledge), in a software engineering program. These recommendations are followed by general pedagogical guidelines, sample courses, and sample curriculum patterns