Engineering Commons^™

Boostnoc: Power Efficient Network-On-Chip Architecture For Near Threshold Computing, Chidhambaranathan Rajamanikkam, Rajesh Jayashankarashridevi, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

While near threshold design space provides a promising approach towards energy-efficient computing, it is plagued by sub-optimal performance. Application characteristics and hardware non-idealities of conventional architectures (optimized for the nominal voltage) prevent us from fully leveraging the potential of NTC systems. Further, the popular approach of increasing the computational core count to compensate for the performance loss severely burdens the on-chip communication fabric with an increased communication demand. In this work, we quantitatively analyze the performance bottleneck createdby a conventional NoC architecture in many-core NTC systems. To reclaim the performance lost due to a sub-optimal NoC, we propose BoostNoC - …

Catching The Flu: Emerging Threats From A Third Party Power Management Unit., Rajesh Jayashankarashridevi, Chidhambaranathan Rajamanikkam, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

Power management units (PMU) have come into the spotlight with energy efficiency becoming a first order constraint in MPSoC designs. To cater to the exponential rise in power events, and to meet the demands of tight power and energy budgets, PMUs are evolving to more complex and intelligent designs. In an era defined by energy efficient computing, a malicious circuit embedded in a third party PMU can adversely affect the operation of the entire MPSoC. This work presents and evaluates two covert security threats, P-VIRUS and DROWSY, designed using a malicious third party PMU. Further, we propose a non-invasive IP …

Swiftgpu: Fostering Energy Efficiency In A Near-Threshold Gpu Through A Tactical Performance Boost, Prabal Basu, Hu Chen, Shamik Saha, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

In this paper, we investigate the challenges of preserving energy-efficiency in a Near-Threshold Computing (NTC) GPU. Two key factors can significantly undermine the efficacy of GPUs at NTC: (a) elongated delays at NTC make the GPU applications severely sensitive toMulti-cycle Latency Datapaths (MLDs) within the GPU pipeline; and (b) process variation (PV) at NTC induces a substantial performance variance. To address these emerging challenges, we propose SwiftGPU - -an energyefficient GPU design paradigm at NTC. SwiftGPU dynamically adjusts the degree of parallelization, and the speed of the MLDs within each stream core of the GPU. The proposed scheme achieves an …

Characterization Of Geolocation Accuracy Of Suomi Npp Advanced Technology Microwave Sounder Measurements, Yang Han, Fuzhong Weng, Xiaolei Zou, Hu Yang, Deron Scott

Electrical and Computer Engineering Faculty Publications

The Advanced Technology Microwave Sounder (ATMS) onboard Suomi National Polar-orbiting Partnership satellite has 22 channels at frequencies ranging from 23 to 183 GHz for probing the atmospheric temperature and moisture under all weather conditions. As part of the ATMS calibration and validation activities, the geolocation accuracy of ATMS data must be well characterized and documented. In this study, the coastline crossing method (CCM) and the land-sea fraction method (LFM) are utilized to characterize and quantify the ATMS geolocation accuracy. The CCM is based on the inflection points of the ATMS window channel measurements across the coastlines, whereas the LFM collocates …

Prada: Combating Voltage Noise In The Noc Power Supply Through Flow-Control And Routing Algorithms., Prabal Basu, Rajesh Jayashankarashridevi, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

Network-on-Chip (NoC) has become the de-facto standard for on-chip communication in MPSoCs. The growing NoC power footprint, increase in the transistor current, and high switching speed of the logic devices, exacerbate the peak power supply noise (PSN) in the NoC power delivery network (PDN). Hence, preserving power supply integrity in the NoC PDN is critical. In this work, we propose PRADA (PSN-aware Runtime Adaptation)-a collection of a novel flow-control protocol (PAF) and an adaptive routing algorithm (PAR), to mitigate PSN in NoCs. Our best scheme achieves 14% and 12% improvements in the regional peak PSN and energy efficiency, with an …

Three-Dimensional Image Reconstruction Using Bundle Adjustment Applied To Multiple Texel Images, Bikalpa Khatiwada, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

The importance of creating 3D imagery is increasing and has many applications in the eld of disaster response, digital elevation models, object recognition, and cultural heritage. Several methods have been proposed to register texel images, which consist of fused lidar and digital imagery. The previous methods were limited to registering up to two texel images or multiple texel swaths having only one strip of lidar data per swath. One area of focus still remains to register multiple texel images to create a 3D model.

The process of creating true 3D images using multiple texel images is described. The texel camera …

Simulation Of A Doppler Lidar System For Autonomous Navigation And Hazard Avoidance During Planetary Landing, Scott E. Budge, David B. Chester

Electrical and Computer Engineering Faculty Publications

The latest mission proposals for exploration of solar system bodies require accurate position and velocity data during the descent phase in order to ensure safe, soft landing at the pre-designated sites. During landing maneuvers, the accuracy of the on-board inertial measurement unit (IMU) may not be reliable due to drift over extended travel times to destinations. NASA has proposed an advanced Doppler lidar system with multiple beams that can be used to accurately determine attitude and position of the landing vehicle during descent, and to detect hazards that might exist in the landing area. In order to assess the effectiveness …

Dynamic Visualization Of Three- Dimensional Images From Multiple Texel Images Created From Fused Ladar/Digital Imagery, Cody C. Killpack, Scott Budge

Electrical and Computer Engineering Faculty Publications

The ability to create three-dimensional (3-D) image models, using registered texel images (fused ladar and digital imagery), is an important topic in remote sensing. These models are automatically generated by matching multiple texel images into a single common reference frame. However, rendering a sequence of independently registered texel images often provides challenges. Although accurately registered, the model textures are often incorrectly overlapped and interwoven when using standard rendering techniques. Consequently, corrections must be done after all the primitives have been rendered by determining the best texture for any viewable fragment in the model. This paper describes a technique to visualize …