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

Engineering Commons

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

Computer Engineering

Open Access Dissertations

2014

Articles 1 - 9 of 9

Full-Text Articles in Engineering

Digital Provenance - Models, Systems, And Applications, Salmin Sultana Oct 2014

Digital Provenance - Models, Systems, And Applications, Salmin Sultana

Open Access Dissertations

Data provenance refers to the history of creation and manipulation of a data object and is being widely used in various application domains including scientific experiments, grid computing, file and storage system, streaming data etc. However, existing provenance systems operate at a single layer of abstraction (workflow/process/OS) at which they record and store provenance whereas the provenance captured from different layers provide the highest benefit when integrated through a unified provenance framework. To build such a framework, a comprehensive provenance model able to represent the provenance of data objects with various semantics and granularity is the first step. In this …


Shape From Inconsistent Silhouette: Reconstruction Of Objects In The Presence Of Segmentation And Camera Calibration Error, Amy Tabb Oct 2014

Shape From Inconsistent Silhouette: Reconstruction Of Objects In The Presence Of Segmentation And Camera Calibration Error, Amy Tabb

Open Access Dissertations

Silhouettes are useful features to reconstruct the object shape when the object is textureless or the shape classes of objects are unknown. In this dissertation, we explore the problem of reconstructing the shape of challenging objects from silhouettes under real-world conditions such as the presence of silhouette and camera calibration error. This problem is called the Shape from Inconsistent Silhouettes problem. A psuedo-Boolean cost function is formalized for this problem, which penalizes differences between the reconstruction images and the silhouette images, and the Shape from Inconsistent Silhouette problem is cast as a psuedo-Boolean minimization problem. We propose a memory and …


Image Analysis Using Visual Saliency With Applications In Hazmat Sign Detection And Recognition, Bin Zhao Oct 2014

Image Analysis Using Visual Saliency With Applications In Hazmat Sign Detection And Recognition, Bin Zhao

Open Access Dissertations

Visual saliency is the perceptual process that makes attractive objects "stand out" from their surroundings in the low-level human visual system. Visual saliency has been modeled as a preprocessing step of the human visual system for selecting the important visual information from a scene. We investigate bottom-up visual saliency using spectral analysis approaches. We present separate and composite model families that generalize existing frequency domain visual saliency models. We propose several frequency domain visual saliency models to generate saliency maps using new spectrum processing methods and an entropy-based saliency map selection approach. A group of saliency map candidates are then …


Functional Programming Abstractions For Weakly Consistent Systems, Sivaramakrishnan Krishnamoorthy Chandrasekaran Oct 2014

Functional Programming Abstractions For Weakly Consistent Systems, Sivaramakrishnan Krishnamoorthy Chandrasekaran

Open Access Dissertations

In recent years, there has been a wide-spread adoption of both multicore and cloud computing. Traditionally, concurrent programmers have relied on the underlying system providing strong memory consistency, where there is a semblance of concurrent tasks operating over a shared global address space. However, providing scalable strong consistency guarantees as the scale of the system grows is an increasingly difficult endeavor. In a multicore setting, the increasing complexity and the lack of scalability of hardware mechanisms such as cache coherence deters scalable strong consistency. In geo-distributed compute clouds, the availability concerns in the presence of partial failures prohibit strong consistency. …


Embodied Interaction With Visualization And Spatial Navigation In Time-Sensitive Scenarios, Yu-Ting Li Oct 2014

Embodied Interaction With Visualization And Spatial Navigation In Time-Sensitive Scenarios, Yu-Ting Li

Open Access Dissertations

Paraphrasing the theory of embodied cognition, all aspects of our cognition are determined primarily by the contextual information and the means of physical interaction with data and information. In hybrid human-machine systems involving complex decision making, continuously maintaining a high level of attention while employing a deep understanding concerning the task performed as well as its context are essential. Utilizing embodied interaction to interact with machines has the potential to promote thinking and learning according to the theory of embodied cognition proposed by Lakoff. Additionally, the hybrid human-machine system utilizing natural and intuitive communication channels (e.g., gestures, speech, and body …


Automatic Translation Of Non-Repetitive Openmp To Mpi, Fahed Jubair Oct 2014

Automatic Translation Of Non-Repetitive Openmp To Mpi, Fahed Jubair

Open Access Dissertations

Cluster platforms with distributed-memory architectures are becoming increasingly available low-cost solutions for high performance computing. Delivering a productive programming environment that hides the complexity of clusters and allows writing efficient programs is urgently needed. Despite multiple efforts to provide shared memory abstraction, message-passing (MPI) is still the state-of-the-art programming model for distributed-memory architectures. ^ Writing efficient MPI programs is challenging. In contrast, OpenMP is a shared-memory programming model that is known for its programming productivity. Researchers introduced automatic source-to-source translation schemes from OpenMP to MPI so that programmers can use OpenMP while targeting clusters. Those schemes limited their focus on …


Usability Of Immersive Virtual Reality Input Devices, Christopher G. Mankey Oct 2014

Usability Of Immersive Virtual Reality Input Devices, Christopher G. Mankey

Open Access Dissertations

This research conducts a usability analysis of human interface devices within an Immersive Virtual Reality Environment. The analysis is carried out for two different interface devices, a commercially available Intersense © Wand and a home built pinch glove and wireless receiver. Users were asked to carry out a series of minor tasks involving placement of shaped blocks into corresponding holes within an Immersive Virtual Reality Environment. Performance was evaluated in terms of speed, accuracy and precision via the collection of completion times, errors made and the precision of motion during the experiment.


Design Of Robust Spin-Transfer Torque Magnetic Random Access Memories For Ultralow Power High Performance On-Chip Cache Applications, Xuanyao Fong Jul 2014

Design Of Robust Spin-Transfer Torque Magnetic Random Access Memories For Ultralow Power High Performance On-Chip Cache Applications, Xuanyao Fong

Open Access Dissertations

Spin-transfer torque magnetic random access memories (STT-MRAMs) based on magnetic tunnel junction (MTJ) has become the leading candidate for future universal memory technology due to its potential for low power, non-volatile, high speed and extremely good endurance. However, conflicting read and write requirements exist in STT-MRAM technology because the current path during read and write operations are the same. Read and write failures of STT-MRAMs are degraded further under process variations. The focus of this dissertation is to optimize the yield of STT- MRAMs under process variations by employing device-circuit-architecture co-design techniques. A devices-to-systems simulation framework was developed to evaluate …


A Method For Clustering High-Dimensional Data Using 1d Random Projections, Sangchun Han Jan 2014

A Method For Clustering High-Dimensional Data Using 1d Random Projections, Sangchun Han

Open Access Dissertations

Clustering high-dimensional data is more difficult than clustering low-dimensional data. The problem is twofold. First, there is an efficiency problem related to the data size, which increases with the dimensionality. Second, there is an effectiveness problem related to the fact that the mere existence of clusters in sample sets of high dimensions is questionable, as empirical samples hardly tend to cluster together in a meaningful fashion. The current approach to addressing this issue is to seek clusters in embedded subspaces of the original space. However, as dimensionality increases, a naive exhaustive search among all subspaces becomes exponentially more complex, which …