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Full-Text Articles in Computer Engineering

A Graduate Education In Software Management And The Software Business For Mid-Career Professionals, Ray Bareiss, Gladys Mercier Feb 2010

A Graduate Education In Software Management And The Software Business For Mid-Career Professionals, Ray Bareiss, Gladys Mercier

Ray Bareiss

Given the unique nature of the software business, the faculty of Carnegie Mellon University’s Silicon Valley campus concluded that mid-career software professionals would be better served by a tailored master’s degree focusing on software management and more broadly on the business of software than by a typical MBA. Our software management master’s program integrates business, technical, and soft skills to prepare our students for technical leadership in their current companies or in entrepreneurial ventures. Our initial program built on the strengths of Carnegie Mellon’s world-class software engineering education. We targeted students working in large companies, engaged in large-scale enterprise software …


Coaching Via Cognitive Apprenticeship, Ray Bareiss, Martin Radley Feb 2010

Coaching Via Cognitive Apprenticeship, Ray Bareiss, Martin Radley

Ray Bareiss

At Carnegie Mellon’s Silicon Valley campus we employ a learn by- doing educational approach in which nearly all student learning, and thus instruction, is in the context of realistic, team based projects. Consequently, we have adopted coaching as our predominant teaching model. In this paper we reflect on our experience with the nature of teaching by coaching using a framework derived from Cognitive Apprenticeship, and explain how we employ the techniques it suggests in our teaching. We also discuss a range of instructional tensions that arise in teaching by coaching and present a survey of student attitudes regarding the effectiveness …


Upper Bounds On The Number Of Channels To Ensure Collision-Free Communications In Multi-Channel Wireless Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2009

Upper Bounds On The Number Of Channels To Ensure Collision-Free Communications In Multi-Channel Wireless Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

Recent studies have found that using multiple channels can separate concurrent transmissions and significantly improve network throughput. However, these studies have only considered wireless nodes that are equipped with omni-directional antennas, which have high interference. On the other hand, other researchers have found that using directional antennas in wireless networks can reduce interference and improve the network performance. But their studies have only considered single channel to be used in wireless networks with directional antennas. Thus, integrating the two technologies of multiple channels and directional antennas together can potentially bring more benefits. Some previous works have studies the capacity on …


User Security Behavior On Wireless Networks: An Empirical Study, Tim Chenoweth, Robert Minch, Sharon Tabor Sep 2009

User Security Behavior On Wireless Networks: An Empirical Study, Tim Chenoweth, Robert Minch, Sharon Tabor

Robert P. Minch

Wireless networks are rapidly becoming ubiquitous but are often insecure and leave users responsible for their own security. We empirically study whether users are successfully securing their client computers when using wireless networks. Automated techniques are used that scan users' machines after they associate with a university wireless network. This determines whether a firewall is being used and what TCP ports are open. Results show that over 9% of 3,331 unique computers scanned were not using a properly configured firewall. In addition, almost 9% had at least one TCP port open, with almost 6% having open ports with significant security …


Software Engineering Education At Carnegie Mellon University: One University; Programs Taught In Two Places, Ray Bareiss, Mel Rosso-Llopart Dec 2008

Software Engineering Education At Carnegie Mellon University: One University; Programs Taught In Two Places, Ray Bareiss, Mel Rosso-Llopart

Ray Bareiss

Teaching Software Engineering to professional master’s students is a challenging endeavor, and arguably for the past 20 years, Carnegie Mellon University has been quite successful. Although CMU teaches Software Engineering at sites world-wide and uses different pedagogies, the goal of the curriculum -- to produce world-class software engineers -- remains constant. This paper will discuss two of the most mature versions of Carnegie Mellon’s Software Engineering program -- the main campus program and its “daughter program” at the Silicon Valley Campus. We discuss the programs with respect to the dimensions of curriculum, how students work and learn, how faculty teach, …


Developing Software Engineering Leaders At Carnegie Mellon Silicon Valley, Ray Bareiss, Todd Sedano Dec 2008

Developing Software Engineering Leaders At Carnegie Mellon Silicon Valley, Ray Bareiss, Todd Sedano

Ray Bareiss

The Carnegie Mellon’s Silicon Valley Campus offers a master’s degree in Software Engineering, with technical and development management tracks, targeted at working software professionals in Silicon Valley. We believe the program to be unique in that it is entirely team-based and project-centered. Students learn by doing as they are coached just in time by faculty in the context of their work on authentic projects, and they are evaluated based on what they produce. In response to our interactions with an industry characterized by innovation and short project development timelines, the program evolved from one focused on “high ceremony” processes to …


Developing Software Engineering Leaders At Carnegie Mellon Silicon Valley, Ray Bareiss, Todd Sedano Dec 2008

Developing Software Engineering Leaders At Carnegie Mellon Silicon Valley, Ray Bareiss, Todd Sedano

Todd Sedano

The Carnegie Mellon’s Silicon Valley Campus offers a master’s degree in Software Engineering, with technical and development management tracks, targeted at working software professionals in Silicon Valley. We believe the program to be unique in that it is entirely team-based and project-centered. Students learn by doing as they are coached just in time by faculty in the context of their work on authentic projects, and they are evaluated based on what they produce. In response to our interactions with an industry characterized by innovation and short project development timelines, the program evolved from one focused on “high ceremony” processes to …


Building A Business On Open Source Software, Tony Wasserman Dec 2008

Building A Business On Open Source Software, Tony Wasserman

Tony Wasserman

For many years, free and open source software was exclusively associated with the research community, in contrast to the closed source products developed by commercial software vendors. Over the past decade, there has been a vast increase in the availability of open source software, growing from such projects as Linux and Apache. Open source software is being widely adopted in industry, which has led to numerous business opportunities for entrepreneurs and vendors. This activity is having a disruptive effect on the software industry that has affected even the largest software vendors. This paper describes the emergence of open source business, …


Throughput And Delay In Wireless Sensor Networks Using Directional Antennas, Hong-Ning Dai Dec 2008

Throughput And Delay In Wireless Sensor Networks Using Directional Antennas, Hong-Ning Dai

Hong-Ning Dai

Most of studies only consider that wireless sensor networks are equipped with only omni-directional antennas, which can cause high collisions. It is shown that the per node throughput in such networks is decreased with the increased number of nodes. Thus, the transmission with multiple short-range hops is preferred to reduce the interference. However, other studies show that the transmission delay increases with the increased number of hops.

In this paper, we consider using directional antennas in wireless sensor networks. We have found that using directional antennas not only can increase the throughput capacity but also can decrease the delay by …


Collision-Tolerant Transmission With Narrow-Beam Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu, Bo Li Oct 2008

Collision-Tolerant Transmission With Narrow-Beam Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu, Bo Li

Hong-Ning Dai

The application of directional antennas in wireless ad hoc networks brings numerous benefits, such as increased spatial reuse and mitigated interference. Most MAC protocols with directional antennas are based on the RTS/CTS mechanism which works well in wireless ad hoc networks using omni-directional antennas. However, RTS/CTS frames cannot mitigate the interference completely. Besides, they also contribute a lot to the performance overhead. This paper studies the problem from a new perspective. We have found that the transmission success probability under directional transmission and directional reception is quite high when the antenna beamwidth is quite narrow. Motivated by the analytical results, …


A Framework For Evaluating Managerial Styles In Open Source Projects, Tony Wasserman, Eugenio Capra Dec 2007

A Framework For Evaluating Managerial Styles In Open Source Projects, Tony Wasserman, Eugenio Capra

Tony Wasserman

This paper presents the Software Project Governance Framework (SPGF) for characterizing management of software projects, based on mechanisms used for communication and collaboration, the organizational structure of projects, and testing and quality assurance procedures. The framework was developed and validated from interviews and surveys with leaders of more than 70 commercial and community based software projects, including both closed and open source projects.


On Collision-Tolerant Transmission With Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2007

On Collision-Tolerant Transmission With Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

The application of directional antennas in wireless networks brings numerous benefits, such as increased spatial reuse and mitigated interferences. Most MAC protocols with directional antennas are based on the RTS/CTS mechanism which works well in wireless networks using omni-directional antennas. However, RTS/CTS frames cannot mitigate the interfering nodes completely. Besides, they also contribute a lot to the performance overhead. This paper studies the problem from a new perspective. We analyze the transmission success probability under directional transmission and directional reception when the antenna beamwidth is quite narrow. Motivated by the analytical results, we design a lightweight MAC protocol without RTS/CTS …


On The Capacity Of Multi-Channel Wireless Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Raymond Chi-Wing Wong, Min-You Wu Dec 2007

On The Capacity Of Multi-Channel Wireless Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Raymond Chi-Wing Wong, Min-You Wu

Hong-Ning Dai

The capacity of wireless ad hoc networks is affected by two key factors: the interference among concurrent transmissions and the number of simultaneous transmissions on a single interface. Recent studies found that using multiple channels can separate concurrent transmissions and greatly improve network throughput. However, those studies only consider that wireless nodes are equipped with only omnidirectional antennas, which cause high collisions. On the other hand, some researchers found that directional antennas bring more benefits such as reduced interference and increased spatial reuse compared with omnidirectional antennas. But, they only focused on a single-channel network which only allows finite concurrent …


Evaluating Software Engineering Processes In Commercial And Community Open Source Projects, Tony Wasserman, Eugenio Capra Apr 2007

Evaluating Software Engineering Processes In Commercial And Community Open Source Projects, Tony Wasserman, Eugenio Capra

Tony Wasserman

We describe a current study for obtaining information about management of commercial and community open source projects. We have interviewed and surveyed leaders of more than 75 open source projects. Questions focused on the styles of leadership and communication, with a technical focus on testing and quality assurance processes. This paper describes the methods used to identify and contact subjects, as well as the questions posed and some results.


Using Flossmole Data In Determining Business Readiness Ratings, Tony Wasserman, Ashutosh Das Dec 2006

Using Flossmole Data In Determining Business Readiness Ratings, Tony Wasserman, Ashutosh Das

Tony Wasserman

This paper is a preliminary report on using FLOSSmole data retrieved from open source repositories (forges) to calculate Business Readiness Rating scores.


Methods And Tools For Developing Interactive Information Systems: An Historical Perspective, Tony Wasserman Dec 2006

Methods And Tools For Developing Interactive Information Systems: An Historical Perspective, Tony Wasserman

Tony Wasserman

This paper describes the evolution of hardware and software technology over the past three decades, focusing on approaches for building interactive information systems and web applications. Successive generations of technology have used advances in hardware and software technology, along with increasingly sophisticated development methods and tools, to reduce development times and to produce a better user experience. After describing the key technology characteristics of each generation, this paper also describes the evolution of a specific methodology, User Software Engineering, from its origins in the 1970’s to its applicability to the development of modern applications.


A Busy-Tone Based Mac Scheme For Wireless Ad Hoc Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2006

A Busy-Tone Based Mac Scheme For Wireless Ad Hoc Networks Using Directional Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

Applying directional antennas in wireless ad hoc networks offers numerous benefits, such as extended communication range, increased spatial reuse, improved capacity and suppressed interference. However, directional antennas can cause new location-dependent carrier sensing problems, such as new hidden terminal and deafness problems, which can cause severe penalties to the performance. Recently, a few schemes have been proposed to tackle these problems. However, these methods can provide limited solutions on the hidden terminal and deafness problems. We propose a new MAC protocol, termed the busy-tone based directional medium access control (BT-DMAC) protocol. When the transmission is in progress, the sender and …


An Overview Of Mac Protocols With Directional Antennas In Wireless Ad Hoc Networks, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu Dec 2005

An Overview Of Mac Protocols With Directional Antennas In Wireless Ad Hoc Networks, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

Although directional antennas have been used in mobile communications systems for quite a long time, realistic applications of directional or smart antennas in wireless ad hoc network have emerged just in recent years. Directional antennas provide numerous benefits, such as higher gains, increased transmission range and low interferences. Wireless medium access schemes play a crucial role in ensuring the efficient and fair sharing of wireless resources. Therefore there are many research work on mechanisms at the wireless medium access layer by using directional antennas. The new features of MAC with directional antennas can cause not only location dependent carrier sensing …


Mil-Std-188-125-1, High-Altitude Emp Protection For Fixed Ground-Based Facilities Mar 2005

Mil-Std-188-125-1, High-Altitude Emp Protection For Fixed Ground-Based Facilities

George H Baker

MIL-STD-188-125-1 establishes minimum requirements and design objectives for high-altitude electromagnetic pulse (HEMP) hardening of fixed ground-based facilities that perform critical, time-urgent command, control, communications, computer, and intelligence (C4I) missions. The standard prescribes minimum performance requirements for low-risk protection from mission-aborting damage or upset due to HEMP environments. It also addresses minimum testing requirements for demonstrating that prescribed performance has been achieved and for verifying that the installed protection subsystem provides the operationally required hardness for the completed facility. Covered fixed ground-based facility types include subscriber terminals and data processing centers, transmitting and receiving communications stations, and relay facilities. Use of …