Open Access. Powered by Scholars. Published by Universities.®

Systems Architecture Commons™

Open Access. Powered by Scholars. Published by Universities.®

781 Full-Text Articles 1,343 Authors 1,171,094 Downloads 122 Institutions

All Articles in Systems Architecture

Faceted Search

781 full-text articles. Page 27 of 32.

Stopwatch: A Cloud Architecture For Timing Channel Mitigation, Peng Li, Debin GAO, Michael K Reiter 2014 Singapore Management University

Stopwatch: A Cloud Architecture For Timing Channel Mitigation, Peng Li, Debin Gao, Michael K Reiter

Research Collection School Of Computing and Information Systems

This article presents StopWatch, a system that defends against timing-based side-channel attacks that arise from coresidency of victims and attackers in infrastructure-as-a-service clouds. StopWatch triplicates each cloud-resident guest virtual machine (VM) and places replicas so that the three replicas of a guest VM are coresident with nonoverlapping sets of (replicas of) other VMs. StopWatch uses the timing of I/O events at a VM’s replicas collectively to determine the timings observed by each one or by an external observer, so that observable timing behaviors are similarly likely in the absence of any other individual, coresident VMs. We detail the design and …


Wireless Location Determination: Using Existing 802.11 Wireless Networks To Determine A Users Location, Travis Calvert 2014 Minnesota State University, Mankato

Wireless Location Determination: Using Existing 802.11 Wireless Networks To Determine A Users Location, Travis Calvert

Journal of Undergraduate Research at Minnesota State University, Mankato

The ability to determine a user’s location through an existing 802.11 wireless network has vast implications in the area of context-aware and pervasive computing. Such abilities have been developed mainly in the Linux environment to date. To maximize its usefulness, a location determination system was developed for the more dominant Windows operation system. While being able to operate outdoors as well as indoors, this system succeeds where traditional GPS (Global Positioning Systems) fail, namely indoor environments. This system could benefit the large number of existing wireless networks and requires no additional hardware; only a few simple software downloads. The ability …


Grounded Ontology – A Proposed Methodology For Emergent Ontology Engineering, Syed Irfan Nabi, Zaheeruddin Asif 2014 Institute of Business Administration, Karachi, Pakistan

Grounded Ontology – A Proposed Methodology For Emergent Ontology Engineering, Syed Irfan Nabi, Zaheeruddin Asif

Business Review

This research posits that a domain ontology developed using text-coding technique contributes in conceptualizing and representing state-of-the-art as given by published research in a particular domain. The motivation behind this research is to provide means for creating a better understanding among the researchers through ontology that would present a clearer picture of any domain of interest. However, a general observation on ontology engineering methods is the domination of personal perspective of ontology developer and/or expert in the resultant ontology. Current ontology engineering methods bestow a primary role to ontology developer. Ontology thus developed is heavily biased towards the domain expert’s …


Structure Preserving Large Imagery Reconstruction, Ju Shen, Jianjun Yang, Sami Taha Abu Sneineh, Bryson Payne, Markus Hitz 2014 University of Dayton

Structure Preserving Large Imagery Reconstruction, Ju Shen, Jianjun Yang, Sami Taha Abu Sneineh, Bryson Payne, Markus Hitz

Computer Science Faculty Publications

With the explosive growth of web-based cameras and mobile devices, billions of photographs are uploaded to the internet. We can trivially collect a huge number of photo streams for various goals, such as image clustering, 3D scene reconstruction, and other big data applications. However, such tasks are not easy due to the fact the retrieved photos can have large variations in their view perspectives, resolutions, lighting, noises, and distortions. Furthermore, with the occlusion of unexpected objects like people, vehicles, it is even more challenging to find feature correspondences and reconstruct realistic scenes. In this paper, we propose a structure-based image …


Synchronicity: Pushing The Envelope Of Fine-Grained Localization With Distributed Mimo, Jie XIONG, Kyle JAMIESON, Karthikeyan SUNDARESAN 2014 Singapore Management University

Synchronicity: Pushing The Envelope Of Fine-Grained Localization With Distributed Mimo, Jie Xiong, Kyle Jamieson, Karthikeyan Sundaresan

Research Collection School Of Computing and Information Systems

Indoor localization of mobile devices and tags has received much attention recently, with encouraging fine-grained localization results available with enough line-of-sight coverage and enough hardware infrastructure. Synchronicity is a location system that aims to push the envelope of highly-accurate localization systems further in both dimensions, requiring less line-of-sight and less infrastructure. With Distributed MIMO network of wireless LAN access points (APs) as a starting point, we leverage the time synchronization that such a network affords to localize with time-difference-of-arrival information at the APs. We contribute novel super-resolution signal processing algorithms and reflection path elimination schemes, yielding superior results even in …


Power Management In The Cluster System, Leping Wang 2014 University of Nebraska-Lincoln

Power Management In The Cluster System, Leping Wang

School of Computing: Dissertations, Theses, and Student Research

With growing cost of electricity, the power management of server clusters has become an important problem. However, most previous researchers have only addressed the challenge in traditional homogeneous environments. Considering the increasing popularity of heterogeneous and virtualized systems, this thesis develops a series of efficient algorithms respectively for power management of heterogeneous soft real-time clusters and a virtualized cluster system. It is built on simple but effective mathematical models. When deployed to a new platform, the software incurs low configuration cost because no extensive performance measurements and profiling are required. Built upon optimization, queuing theory and control theory techniques, our …


Query Analyzer And Manager For Complex Event Processing As A Service, Wilson Higashino, Cedric Eichler, Miriam A M Capretz, Thierry Monteil, M. Beatriz F. Toledo, Patricia Stolf 2014 Western University

Query Analyzer And Manager For Complex Event Processing As A Service, Wilson Higashino, Cedric Eichler, Miriam A M Capretz, Thierry Monteil, M. Beatriz F. Toledo, Patricia Stolf

Electrical and Computer Engineering Publications

Complex Event Processing (CEP) is a set of tools and techniques that can be used to obtain insights from high-volume, high-velocity continuous streams of events. CEP-based systems have been adopted in many situations that require prompt establishment of system diagnostics and execution of reaction plans, such as in monitoring of complex systems. This article describes the Query Analyzer and Manager (QAM) module, a first effort toward the development of a CEP as a Service (CEPaaS) system. This module is responsible for analyzing user-defined CEP queries and for managing their execution in distributed cloud-based environments. Using a language-agnostic internal query representation, …


Evaluation Of Particle Swarm Optimization Applied To Grid Scheduling, Wilson Higashino, Miriam A M Capretz, M. Beatriz F. Toledo 2014 Western University

Evaluation Of Particle Swarm Optimization Applied To Grid Scheduling, Wilson Higashino, Miriam A M Capretz, M. Beatriz F. Toledo

Electrical and Computer Engineering Publications

The problem of scheduling independent users’ jobs to resources in Grid Computing systems is of paramount importance. This problem is known to be NP-hard, and many techniques have been proposed to solve it, such as heuristics, genetic algorithms (GA), and, more recently, particle swarm optimization (PSO). This article aims to use PSO to solve grid scheduling problems, and compare it with other techniques. It is shown that many often-overlooked implementation details can have a huge impact on the performance of the method. In addition, experiments also show that the PSO has a tendency to stagnate around local minima in high-dimensional …


Service Evolution Patterns, Shuying Wang, Wilson Higashino, Michael Hayes, Miriam A M Capretz 2014 Western University

Service Evolution Patterns, Shuying Wang, Wilson Higashino, Michael Hayes, Miriam A M Capretz

Electrical and Computer Engineering Publications

Service evolution is the process of maintaining and evolving existing Web services to cater for new requirements and technological changes. In this paper, a service evolution model is proposed to analyze service dependencies, identify changes on services and estimate impact on consumers that will use new versions of these services. Based on the proposed service evolution model, four service evolution patterns are described: compatibility, transition, split-map, and merge-map. These proposed patterns provide reusable templates to encourage well-defined service evolution while minimizing issues that arise otherwise. They can be applied in the service evolution scenario where a single service is used …


Contextual Anomaly Detection In Big Sensor Data, Michael Hayes, Miriam A M Capretz 2014 Western University

Contextual Anomaly Detection In Big Sensor Data, Michael Hayes, Miriam A M Capretz

Electrical and Computer Engineering Publications

Performing predictive modelling, such as anomaly detection, in Big Data is a difficult task. This problem is compounded as more and more sources of Big Data are generated from environmental sensors, logging applications, and the Internet of Things. Further, most current techniques for anomaly detection only consider the content of the data source, i.e. the data itself, without concern for the context of the data. As data becomes more complex it is increasingly important to bias anomaly detection techniques for the context, whether it is spatial, temporal, or semantic. The work proposed in this paper outlines a contextual anomaly detection …


Coffee: Context Observer For Fast Enthralling Entertainment, Anthony M. Lenz 2014 California Polytechnic State University, San Luis Obispo

Coffee: Context Observer For Fast Enthralling Entertainment, Anthony M. Lenz

Master's Theses

Desktops, laptops, smartphones, tablets, and the Kinect, oh my! With so many devices available to the average consumer, the limitations and pitfalls of each interface are becoming more apparent. Swimming in devices, users often have to stop and think about how to interact with each device to accomplish the current tasks at hand. The goal of this thesis is to minimize user cognitive effort in handling multiple devices by creating a context aware hybrid interface. The context aware system will be explored through the hybridization of gesture and touch interfaces using a multi-touch coffee table and the next-generation Microsoft Kinect. …


Transport Architectures For An Evolving Internet, Keith Winstein '99 2014 Illinois Mathematics and Science Academy

Transport Architectures For An Evolving Internet, Keith Winstein '99

Doctoral Dissertations

In the Internet architecture, transport protocols are the glue between an application’s needs and the network’s abilities. But as the Internet has evolved over the last 30 years, the implicit assumptions of these protocols have held less and less well. This can cause poor performance on newer networks—cellular networks, datacenters—and makes it challenging to roll out networking technologies that break markedly with the past.

Working with collaborators at MIT, I have built two systems that explore an objective-driven, computer-generated approach to protocol design. My thesis is that making protocols a function of stated assumptions and objectives can improve application performance …


Design Of Cpu Simulation Software For Armv7 Instruction Set Architecture, Dillon Tellier 2014 California Polytechnic State University - San Luis Obispo

Design Of Cpu Simulation Software For Armv7 Instruction Set Architecture, Dillon Tellier

Computer Engineering

Simulations have long been a part of the engineering process in both the professional and academic domain. From a pedagogic standpoint, simulations allow students to explore the dynamics of engineering scenarios by controlling variables, taking measurements, and observing behavior which would be difficult or impossible without simulation. One such tool is a CPU simulator used in Cal Poly’s Computer Architecture classes; this software simulates an instruction accurate operation of a computer processor and reports statistics regarding the execution of the supplied compiled machine code. For the last several years Cal Poly’s computer architecture classes have used a previous version of …


A Constrained, Possibilistic Logical Approach For Software System Survivability Evaluation, Yanjun Zuo 2014 University of North Dakota

A Constrained, Possibilistic Logical Approach For Software System Survivability Evaluation, Yanjun Zuo

Accountancy Faculty Publications

In this paper, we present a logical framework to facilitate users in assessing a software system in terms of the required survivability features. Survivability evaluation is essential in linking foreign software components to an existing system or obtaining software systems from external sources. It is important to make sure that any foreign components/systems will not compromise the current system’s survivability properties. Given the increasing large scope and complexity of modern software systems, there is a need for an evaluation framework to accommodate uncertain, vague, or even ill-known knowledge for a robust evaluation based on multi-dimensional criteria. Our framework incorporates user-defined …


Digital Circuit Projects: An Overview Of Digital Circuits Through Implementing Integrated Circuits - Second Edition, Charles W. Kann 2014 Gettysburg College

Digital Circuit Projects: An Overview Of Digital Circuits Through Implementing Integrated Circuits - Second Edition, Charles W. Kann

Open Educational Resources

Digital circuits, often called Integrated Circuits or ICs, are the central building blocks of a Central Processing Unit (CPU). To understand how a computer works, it is essential to understand the digital circuits which make up the CPU. This text introduces the most important of these digital circuits; adders, decoders, multiplexers, D flip-flops, and simple state machines.

What makes this textbook unique is that it puts the ability to understand these circuits into the hands of anyone, from hobbyists to students studying Computer Science. This text is designed to teach digital circuits using simple projects the reader can implement. But …


Porting The Embedded Xinu Operating System To The Raspberry Pi, Eric Biggers 2014 Macalester College

Porting The Embedded Xinu Operating System To The Raspberry Pi, Eric Biggers

Mathematics, Statistics, and Computer Science Honors Projects

This thesis presents a port of a lightweight instructional operating system called Embedded Xinu to the Raspberry Pi. The Raspberry Pi, an inexpensive credit-card-sized computer, has attracted a large community of hobbyists, researchers, and educators since its release in 2012. However, the system-level software running on the Raspberry Pi has been restricted to two ends of a spectrum: complex modern operating systems such as Linux at one end, and very simple hobbyist operating systems or simple “bare-metal” programs at the other end. This project bridges this gap by porting the Embedded Xinu operating system to the Raspberry Pi. Although simple …


Capturing And Analyzing Network Traffic From Common Mobile Devices For Security And Privacy, Billy Overton 2014 East Tennessee State University

Capturing And Analyzing Network Traffic From Common Mobile Devices For Security And Privacy, Billy Overton

Undergraduate Honors Theses

Mobile devices such as tablets and smartphones are becoming more common, and they are holding more information. This includes private information such as contacts, financial data, and passwords. At the same time these devices have network capability with access to the Internet being a prime feature. Little research has been done in observing the network traffic produced by these mobile devices. To determine if private information was being transmitted without user knowledge, the mobile capture lab and a set of procedures have been created to observe, capture and analyze the network traffic produced by mobile devices. The effectiveness of the …


Automatic Objects Removal For Scene Completion, Jianjun Yang, Yin Wang, Honggang Wang, Kun Hua, Wei Wang, Ju Shen 2014 University of North Georgia

Automatic Objects Removal For Scene Completion, Jianjun Yang, Yin Wang, Honggang Wang, Kun Hua, Wei Wang, Ju Shen

Computer Science Faculty Publications

With the explosive growth of Web-based cameras and mobile devices, billions of photographs are uploaded to the Internet. We can trivially collect a huge number of photo streams for various goals, such as 3D scene reconstruction and other big data applications. However, this is not an easy task due to the fact the retrieved photos are neither aligned nor calibrated. Furthermore, with the occlusion of unexpected foreground objects like people, vehicles, it is even more challenging to find feature correspondences and reconstruct realistic scenes. In this paper, we propose a structure-based image completion algorithm for object removal that produces visually …


Semantic Privacy Policies For Service Description And Discovery In Service-Oriented Architecture, Diego Z. Garcia, Miriam A M Capretz, M. Beatriz F. Toledo 2014 Universidade Federal de Ouro Preto

Semantic Privacy Policies For Service Description And Discovery In Service-Oriented Architecture, Diego Z. Garcia, Miriam A M Capretz, M. Beatriz F. Toledo

Electrical and Computer Engineering Publications

Privacy preservation in Service-Oriented Architecture (SOA) is an open problem. This paper focuses on the areas of service description and discovery. The problems in these areas are that currently it is not possible to describe how a service provider deals with information received from a service consumer as well as discover a service that satisfies the privacy preferences of a consumer. There is currently no framework which offers a solution that supports a rich description of privacy policies and their integration in the process of service discovery. Thus, the main goal of this paper is to propose a privacy preservation …


Inequalities And Asymmetries, Tamara Kneese 2014 University of San Francisco

Inequalities And Asymmetries, Tamara Kneese

Media Studies

The availability of data is not evenly distributed. Some organizations, agencies, and sectors are better equipped to gather, use, and analyze data than others. If data is transformative, what are the consequences of defense and security agencies having greater capacity to leverage data than, say, education or social services? Financial wherewithal, technical capacity, and political determinants all affect where data is employed. As data and analytics emerge, who benefits and who doesn't, both at the individual level and the institutional level? What about the asymmetries between those who provide the data and those who collect it? How does uneven data …


Digital Commons powered by bepress