Computer Engineering Commons^™

Using Software-Based Decision Procedures To Control Instruction-Level Execution, William B. Kimball

AFIT Patents

An apparatus, method and program product are provided for securing a computer system. A digital signature of an application is checked, which is loaded into a memory of the computer system configured to contain memory pages. In response to finding a valid digital signature, memory pages containing instructions of the application are set as executable and memory pages other than those containing instructions of the application are set as non-executable. Instructions in executable memory pages are executed. Instructions in non-executable memory pages are prevented from being executed. A page fault is generated in response to an attempt to execute an …

Adaptive Computer‐Generated Forces For Simulator‐Based Training, Expert Systems With Applications, Teck-Hou Teng, Ah-Hwee Tan, Loo-Nin Teow

Research Collection School Of Computing and Information Systems

Simulator-based training is in constant pursuit of increasing level of realism. The transition from doctrine-driven computer-generated forces (CGF) to adaptive CGF represents one such effort. The use of doctrine-driven CGF is fraught with challenges such as modeling of complex expert knowledge and adapting to the trainees’ progress in real time. Therefore, this paper reports on how the use of adaptive CGF can overcome these challenges. Using a self-organizing neural network to implement the adaptive CGF, air combat maneuvering strategies are learned incrementally and generalized in real time. The state space and action space are extracted from the same hierarchical doctrine …

Vehicular Motion Sensor: Developing A Wide-Range Motion Sensing Alarm System, Joshua Isaacson

Senior Honors Theses

Vehicular safety has become a serious concern in recent years. Many drivers have difficulty backing out of parking spaces, especially when large trucks and sport utility vehicles block the peripheral view from smaller vehicles. This can lead to accidents and pedestrian injuries when drivers are unable to see or do not pay careful attention to their surroundings.

Vehicular motion sensor systems can alert drivers of approaching obstacles when attempting to back out of parking spaces with limited visibility. This thesis aims to explain the limitations of current systems and the research conducted by the author to develop a prototype for …

An Experimental Study For Inter-User Interference Mitigation In Wireless Body Sensor Networks, Bin Cao, Yu Ge, Chee Wee Kim, Gang Feng, Hwee-Pink Tan, Yun Li

Research Collection School Of Computing and Information Systems

Inter-user interference degrades the reliability of data delivery in wireless body sensor networks (WBSNs) in dense deployments when multiple users wearing WBSNs are in close proximity to one another. The impact of such interference in realistic WBSN systems is significant but is not well explored. To this end, we investigate and analyze the impact of inter-user interference on packet delivery ratio (PDR) and throughput. We conduct extensive experiments based on the TelosB WBSN platform, considering unslotted carrier sense multiple access (CSMA) with collision avoidance (CA) and slotted CSMA/CA modes in IEEE 802.15.4 MAC, respectively. In order to mitigate interuser interference, …

Clustering Algorithms For Maximizing The Lifetime Of Wireless Sensor Networks With Energy-Harvesting Sensors, Pengfei Zhang, Gaoxi Xiao, Hwee-Pink Tan

Research Collection School Of Computing and Information Systems

Motivated by recent developments in wireless sensor networks (WSNs), we present several efficient clustering algorithms for maximizing the lifetime of WSNs, i.e., the duration till a certain percentage of the nodes die. Specifically, an optimization algorithm is proposed for maximizing the lifetime of a single-cluster network, followed by an extension to handle multi-cluster networks. Then we study the joint problem of prolonging network lifetime by introducing energy-harvesting (EH) nodes. An algorithm is proposed for maximizing the network lifetime where EH nodes serve as dedicated relay nodes for cluster heads (CHs). Theoretical analysis and extensive simulation results show that the proposed …

Evaluating The Presence Of A Victim Cache On An Arm Processor, Lakshmi Vidya Peri

Computer Science Graduate Projects and Theses

Mobile processor is a CPU designed to save power. It is found in mobile computers and cell phones. A CPU chip, designed for portable computers, is typically housed in a smaller chip package, but more importantly, in order to run cooler, it uses lower voltages than its desktop counterpart and has more "sleep mode" capability. A mobile processor can be throttled down to different power levels and/or sections of the chip can be turned off entirely when not in use. ARM is a 32-bit reduced instruction set computer (RISC) instruction set architecture (ISA). The relative simplicity of ARM processors makes …

The Mayaarch3d Project: A 3d Webgis For Analyzing Ancient Architecture And Landscapes, Jennifer Von Schwerin, Heather Richards-Rissetto, Fabio Remondino, Giorgio Agugario, Gabrio Girardi

Department of Anthropology: Faculty Publications

There is a need in the humanities for a 3D WebGIS with analytical tools that allow researchers to analyze 3D models linked to spatially referenced data. Geographic Information Systems (GIS) allow for complex spatial analysis of 2.5D data. For example, they offer bird’s eye views of landscapes with extruded building footprints, but one cannot ‘get on the ground’ and interact with true 3D models from a pedestrian perspective. Meanwhile, 3D models and virtual environments visualize data in 3D space, but analytical tools are simple rotation or lighting effects. The MayaArch3D Project is developing a 3D WebGIS—called QueryArch3D—to allow these two …

The Taxation Of Cloud Computing And Digital Content, David Shakow

All Faculty Scholarship

“Cloud computing” raises important and difficult questions in state tax law, and for Federal taxes, particularly in the foreign tax area. As cloud computing solutions are adopted by businesses, items we view as tangible are transformed into digital products. In this article, I will describe the problems cloud computing poses for tax systems. I will show how current law is applied to cloud computing and will identify the difficulties current approaches face as they are applied to this developing technology.

My primary interest is how Federal tax law applies to cloud computing, particularly as the new technology affects international transactions. …

Advancements And Challenges Towards A Collaborative Framework For 3d Tele-Immersive Social Networking, Davide Andrea Mauro, N. E. O’Connor, D. Monaghan, Marc Gowing, P. Fechteler, P. Eisert, J. Wall, E. Izquierdo, D. S. Alexiadis, P. Daras, R. Mekuria, P. Cesar

Computer Sciences and Electrical Engineering Faculty Research

Social experiences realized through teleconferencing systems are still quite different from face to face meetings. The awareness that we are online and in a, to some extent, lesser real world are preventing us from really engaging and enjoying the event. Several reasons account for these differences and have been identified. We think it is now time to bridge these gaps and propose inspiring and innovative solutions in order to provide realistic, believable and engaging online experiences. We present a distributed and scalable framework named REVERIE that faces these challenges and provides a mix of these solutions. Applications built on top …

A Performance Analysis Of Ws-* (Soap) And Restful Web Services For Implementing Service And Resource Orientated Architectures, Philip Markey, Gary Clynch

Conference Papers

The past number of years have seen the emergence of Service-Oriented Architectures as a dominant architecture for implementing enterprise scale distributed systems. Two main styles of SOA exist, namely SOAP based services and RESTful services. There has been much comment and debate on the pros and cons of each approach to implementing a SOA, a lot of which has surrounded the performance characterictcs of both approaches. In this paper, the authors presents the results of a performance analysis that was conducted on a set of test SOA scenarios implemented using both SOAP and RESTful approaches; in particular the caching capabilities …

Energy-Neutral Scheduling And Forwarding In Environmentally-Powered Wireless Sensor Networks, Alvin Cerdena Valera, Weng Seng Soh, Hwee-Pink Tan

Research Collection School Of Computing and Information Systems

In environmentally-powered wireless sensor networks (EPWSNs), low latency wakeup scheduling and packet forwarding is challenging due to dynamic duty cycling, posing time-varying sleep latencies and necessitating the use of dynamic wakeup schedules. We show that the variance of the intervals between receiving wakeup slots affects the expected sleep latency: when the variance of the intervals is low (high), the expected latency is low (high). We therefore propose a novel scheduling scheme that uses the bit-reversal permutation sequence (BRPS) – a finite integer sequence that positions receiving wakeup slots as evenly as possible to reduce the expected sleep latency. At the …

Low Cost Dynamic Architecture Adaptation Schemes For Drowsy Cache Management, Nitin Prakash

Masters Theses 1911 - February 2014

Energy consumption and speed of execution have long been recognized as conflicting requirements for processor design. In this work, we have developed a low-cost dynamic architecture adaptation scheme to save leakage power in caches. This design uses voltage scaling to implement drowsy caches. The importance of a dynamic scheme for managing drowsy caches, arises from the fact that not only does cache behavior change from one application to the next, but also during different phases of execution within the same application. We discuss various implementations of our scheme that provide a tradeoff between granularity of control and design complexity. …

The Evolution Of Successful Service-Learning Courses In The Computing Curriculum: From Infancy To Innovation, Jean F. Coppola Phd, Susan Feather-Gannon, Catharina Daniels, Nancy Lynch Hale, Pauline Mosley

Wilson Center for Social Entrepreneurship

The purpose of this paper is to relate the evolution of successful service-learning courses in a school of computer science and information systems spanning over a 20-year period. The authors share their experiences in developing technology-based service-learning courses for both majors and non-majors. Most recently, these courses have enabled undergraduate first-year students to be exposed to exciting technologies, such as robotics and mobile app development. The challenges, benefits, and lessons learned are discussed.

Approaches That Will Yield Greater Success When Implementing Self-Administered Electronic Data Capture Ict Systems In The Developing World With An Illiterate Or Semi-Literate Population, Stanley J. Mierzwa, Samir Souidi, Irene Friedland, Sarah A. Littlefield, Lauren L. Katzen, Craig Savel, Deborah Boccio, Saumya Ramarao

Reproductive Health

The Information Technology (IT) Group at the Population Council responded to a need for a technology solution that would help researchers obtain more accurate responses to survey questions that concerned subject matter of a sensitive nature. The IT Group had three goals: (1) to enhance research by obtaining the best data possible, (2) to operate successfully in the local environment and be welcomed by the local populations, and (3) to increase the efficiency and cost-effectiveness of the survey process. This paper outlines approaches to consider when designing and implementing self-administered information and communications technology (ICT) questionnaires in developing countries, and …

A P2p Computing System For Overlay Networks, Grzegorz Chmaj, Krzysztof Walkowiak

Electrical & Computer Engineering Faculty Research

A distributed computing system is able to perform data computation and distribution of results at the same time. The input task is divided into blocks, which are then sent to system participants that offer their resources in order to perform calculations. Next, a partial result is sent back by the participants to the task manager (usually one central node). In the case when system participants want to get the final result, the central node may become overloaded, especially if many nodes request the result at the same time. In this paper we propose a novel distributed computation system, which does …

Substantive Collaboration: Are We Ready To Lead?, Mark Askren

Information Technology Services: Publications

Although MOOCs have received the most attention in higher education this year, another issue is affecting colleges and universities and the IT community on a much broader scale: the perception that the higher education business model is “broken.” This isn’t an IT problem by definition, but IT leaders have not contributed effectively to a solution. At least not yet. So what can we, as IT leaders, do individually and collectively to change the outcome? The answer is clear. We have to collaborate. Substantially. And in ways that are far-reaching and very challenging. We have to change our core processes and …

A New Simplified Federated Single Sign-On System, Chen Liang

Masters

The work presented in this MPhil thesis addresses this challenge by developing a new simplified FSSO system that allows end-users to access desktop systems, web-based services/applications and non-web based services/applications using one authentication process. This new system achieves this using two major components: an “Authentication Infrastructure Integration Program (AIIP)" and an “Integration of Desktop Authentication and Web-based Authentication (IDAWA)." The AIIP acquires Kerberos tickets (for end-users who have been authenticated by a Kerberos single sign-on system in one net- work domain) from Kerberos single sign-on systems in different network domains without establishing trust between these Kerberos single sign-on systems. The …

The Nebula Future Internet Architecture, Christopher S. Yoo, Ken Birman, Robert Broberg, Matthew Caesar, Douglas Comer, Chase Cotton, Michael J. Freed, Andreas Haeberlen, Zachary G. Ives, Arvind Krishnamurthy, William Lehr, Boon Thau Loo, David Mazieres, Antonio Nicolosi, Jonathan M. Smith, Ion Stoica, Robbert Van Renesse, Michael Walfish, Hakim Weatherspoon

All Faculty Scholarship

NEBULA is a proposal for a Future Internet Architecture. It is based on the assumptions that: (1) cloud computing will comprise an increasing fraction of the application workload offered to an Internet, and (2) that access to cloud computing resources will demand new architectural features from a network. Features that we have identified include dependability, security, flexibility and extensibility, the entirety of which constitute resilience. NEBULA provides resilient networking services using ultrareliable routers, an extensible control plane and use of multiple paths upon which arbitrary policies may be enforced. We report on a prototype system, Zodiac, that incorporates these latter …