Computer Engineering Commons^™

Approximate Computing: An Integrated Cross-Layer Framework, Swagath Venkataramani

Open Access Dissertations

A new design approach, called approximate computing (AxC), leverages the flexibility provided by intrinsic application resilience to realize hardware or software implementations that are more efficient in energy or performance. Approximate computing techniques forsake exact (numerical or Boolean) equivalence in the execution of some of the application’s computations, while ensuring that the output quality is acceptable. While early efforts in approximate computing have demonstrated great potential, they consist of ad hoc techniques applied to a very narrow set of applications, leaving in question the applicability of approximate computing in a broader context.

The primary objective of this thesis is to …

Implementing A Wireless Monitoring Solution For A Biomechanical Telemetry System, Hyung Suk Kim

Open Access Theses

Sport-related Traumatic Brain Injury (TBI) is one of the major concerns for collision based sports athletes and their families. The ability to measure impacts on the head is imperative to monitor brain injury and prevent serious TBI. Recent research by the Purdue Neurotrauma Group (PNG) indicates that accumulation of subconcussive impacts may cause permanent neurological damage. Currently available commercial impact monitoring systems are designed as an event-based models which collect impact data above pre-determined acceleration thresholds. To track long-term effects of sub-concussive impacts, event-based modeling is inadequate. The PNG developed a biomechanical sports telemetry system that is capable of storing …

Improvement Of A Biomechanical Telemetry System Hardware Platform, Soon Ho Kwon

Open Access Theses

Traumatic brain injuries (TBI) while playing sports are a major concern for the general public today. Recently, studies have shown that repetitive subconcussive hits can lead to neurological disorders. In order to prevent the athletes from suffering traumatic brain injuries, many organizations related to contact based sports and the military employ commercialized head impact telemetry systems. However, a majority of the commercialized systems is event based which only collects the linear acceleration that exceeds a certain threshold. To accurately record and utilize the data from the impact telemetry system, it is necessary to record all the linear and angular acceleration …

Three Dimensional Moving Pictures With A Single Imager And Microfluidic Lens, Chao Liu

Open Access Dissertations

Three-dimensional movie acquisition and corresponding depth data is commonly generated from multiple cameras and multiple views. This technology has high cost and large size which are limitations for medical devices, military surveillance and current consumer products such as small camcorders and cell phone movie cameras. This research result shows that a single imager, equipped with a fast-focus microfluidic lens, produces a highly accurate depth map. On test material, the depth is found to be an average Root Mean Squared Error (RMSE) of 3.543 gray level steps (1.38\%) accuracy compared to ranging data. The depth is inferred using a new Extended …

Exploring Spin-Transfer-Torque Devices And Memristors For Logic And Memory Applications, Zoha Pajouhi

Open Access Dissertations

As scaling CMOS devices is approaching its physical limits, researchers have begun exploring newer devices and architectures to replace CMOS.

Due to their non-volatility and high density, Spin Transfer Torque (STT) devices are among the most prominent candidates for logic and memory applications. In this research, we first considered a new logic style called All Spin Logic (ASL). Despite its advantages, ASL consumes a large amount of static power; thus, several optimizations can be performed to address this issue. We developed a systematic methodology to perform the optimizations to ensure stable operation of ASL.

Second, we investigated reliable design of …

Improving The Resilience Of Cyber-Physical Systems Under Strategic Adversaries, Paul Wood

Open Access Dissertations

Renewable energy resources challenge traditional energy system operations by substituting the stability and predictability of fossil fuel based generation with the unreliability and uncertainty of wind and solar power. Rising demand for green energy drives grid operators to integrate sensors, smart meters, and distributed control to compensate for this uncertainty and improve the operational efficiency of the grid. Real-time negotiations enable producers and consumers to adjust power loads during shortage periods, such as an unexpected outage or weather event, and to adapt to time-varying energy needs. While such systems improve grid performance, practical implementation challenges can derail the operation of …

Fast Voxel Line Update For Time-Space Image Reconstruction, Xiao Wang

Open Access Theses

Recent applications of model-based iterative reconstruction(MBIR) algorithm to time-space Computed Tomography (CT) have shown that MBIR can greatly improve image quality by increasing resolution as well as reducing noise and some artifacts. Among the various iterative methods that have been studied for MBIR, iterative coordinate descent(ICD) has been found to have relatively low overall computational requirements due to its fast convergence. However, high computational cost and long reconstruction times remain as a barrier to the use of MBIR in practical applications. This disadvantage is especially prominent in time-space reconstruction because of the large volume of data. This thesis presents a …

Realization And Evaluation Of A 3-Degrees-Of-Freedom Mouse Model, Udayan Umapathi

Open Access Theses

Kinesiology research has shown that translation and rotation are inseparable actions in the real world. Motivated by this fact, this thesis explores a model for the computer mouse, the new addition being rotational input about vertical axis of a mouse. We realize our model through Mushaca, a 3-degrees-of-freedom mouse (3DOF mouse) that can sense rotation, in addition to sensing XY planar translation. The thesis presents two realizations of Mushaca - namely a MEMS version that uses accelerometer and gyroscope, and an optical sensor version that uses two optical sensors. Through a controlled user study we try to find out if …