Digital Commons Network^™

Development Of Experimental Test Rig For Internally Geared Screw Compressors, Aleksander Krupa, Ahmed Kovacevic, Matthew Read

International Compressor Engineering Conference

No abstract provided.

Cfd Study Of The Internal Leakage Of A Four-Intersecting-Vane Expander, Anarghya Ananda Murthy, Alison Subiantoro

International Compressor Engineering Conference

No abstract provided.

Peak Demand Limiting Packaged Rooftop Hvac Unit Coordination, Joshua Devenezia, Todd Rossi, Michael Muller

International High Performance Buildings Conference

No abstract provided.

Evaluation Of A Graphene Enhanced Photocatalytic Oxidation Device, Paul Gerard Hoertz, Stephen Kujak, Kathleen Owen

International High Performance Buildings Conference

No abstract provided.

Performance Modeling And Analysis Of A Thermoelectric Building Envelope For Space Heating, Xiaoli Liu, Ming Qu, Kazuaki Yazawa, Jorge Kohanoff, Piotr Chudzinski, Lorenzo Stella, Brian Norton, Niall Holmes, Ruchita Jani, Hongxi Yin, Conrad Johnston

International High Performance Buildings Conference

No abstract provided.

Assessment Of Short-Term Aquifer Thermal Energy Storage For Energy Management In Greenhouse Horticulture: Modeling And Optimization, Queralt Altes-Buch, Tanguy Robert, Sylvain Quoilin, Vincent Lemort

International High Performance Buildings Conference

No abstract provided.

Performance Prediction And Calibration Of A Clean-Room Air Conditioner Using An Embedded Artificial Neural Network, Myung-Sup Yoon, Dong-Hyuk Yi, Myung-Kyo Seo, Seung-Yup Ryu

International Refrigeration and Air Conditioning Conference

No abstract provided.

Approximate Calculation Of On-Off Vapor Refrigeration Cycle Efficiency Through A Pseudo-Stationary Models, Vinicius A. Matsuda, Eduardo Postingel Falcetti, Cristiano Bigonha Tibiriça, Luben Cabezas Gomes

International Refrigeration and Air Conditioning Conference

No abstract provided.

A Figure Of Merit To Characterize The Efficacy Of Evaporation From Porous Microstructured Surfaces, M. Bongarala, H. Hu, J.A. Weibel, S.V. Garimella

CTRC Research Publications

Evaporation from porous structured surfaces is encountered in a variety of applications including electronics cooling, desalination, and solar energy generation. Of major interest in the design of thermal systems for such applications is a prediction of the heat and mass transfer rates during evaporation from these surfaces. The present study develops a figure of merit (FOM) that characterizes the efficacy of evaporative heat transfer from microstructured surfaces. Geometric quantities such as the contact line length per unit area, porosity, and contact angle that are independent of details of the surface structure are utilized to develop the FOM, allowing for flexibility …

Data Analytics For Evaluating Campus Energy Use, Whitman Jerman, Soowon Chang, William Hutzel

International High Performance Buildings Conference

No abstract provided.

Smart Low-Cost Thermal Imaging Acquisition Towards Personal Comfort Prediction, Ati Soleimanijavid, Iason Konstantzos

International High Performance Buildings Conference

No abstract provided.

Investigating The Quality Of The Correlation Between Indoor Environmental Factors And Human Perception, Ilaria Pittana, Federica Morandi, Francesca Cappelletti, Andrea Gasparella

International High Performance Buildings Conference

No abstract provided.

The Effect Of Dynamic Wetting Behavior On Boiling Heat Transfer Mechanisms During Bubble Growth And Departure, Taylor P. Allred, Justin Weibel, Suresh V. Garimella

CTRC Research Publications

Decades of prior study has yet to fully disentangle the complex transport mechanisms that are attributed to highly effective heat transfer during boiling. Rational design of enhanced surfaces to maintain lower surface temperatures during boiling requires improved insight into the individual heat transfer processes and their dependence on surface characteristics. This study seeks to advance the understanding of the fundamental role that surface wettability plays in determining the relative contributions of different heat transfer mechanisms and on the overall heat transfer efficacy during bubble growth. Two-phase, diabatic simulations of single bubble growth considering interfacial phase change and a custom dynamic …

Lifespan And Efficiency Gain For Outdoor Electronic Systems From Radiative Cooling: A Case Study On Distribution Transformers, J. Peoples, F. Arentz, Y. Fang, C. Mohan, J. Li, X. Li, X. Ruan

CTRC Research Publications

No abstract provided.

Reflections On Software Failure Analysis, Paschal C. Amusuo, Aishwarya Sharma, Siddharth R. Rao, Abbey Vincent, James C. Davis

Department of Electrical and Computer Engineering Faculty Publications

Failure studies are important in revealing the root causes, behaviors, and life cycle of defects in software systems. These studies either focus on understanding the characteristics of defects in specific classes of systems or the characteristics of a specific type of defect in the systems it manifests in. Failure studies have influenced various software engineering research directions, especially in the area of software evolution, defect detection, and program repair.

In this paper, we reflect on the conduct of failure studies in software engineering. We reviewed a sample of 52 failure study papers. We identified several recurring problems in these studies, …

Sok: Analysis Of Software Supply Chain Security By Establishing Secure Design Properties, Chinenye Okafor, Taylor R. Schorlemmer, Santiao Torres-Arias, James C. Davis

Department of Electrical and Computer Engineering Faculty Publications

This paper systematizes knowledge about secure software supply chain patterns. It identifies four stages of a software supply chain attack and proposes three security properties crucial for a secured supply chain: transparency, validity, and separation. The paper describes current security approaches and maps them to the proposed security properties, including research ideas and case studies of supply chains in practice. It discusses the strengths and weaknesses of current approaches relative to known attacks and details the various security frameworks put out to ensure the security of the software supply chain. Finally, the paper highlights potential gaps in actor and operation-centered …

Exploiting Input Sanitization For Regex Denial Of Service, Efe Barlas, Xin Du, James C. Davis

Department of Electrical and Computer Engineering Faculty Publications

Web services use server-side input sanitization to guard against harmful input. Some web services publish their sanitization logic to make their client interface more usable, e.g., allowing clients to debug invalid requests locally. However, this usability practice poses a security risk. Specifically, services may share the regexes they use to sanitize input strings — and regex-based denial of service (ReDoS) is an emerging threat. Although prominent service outages caused by ReDoS have spurred interest in this topic, we know little about the degree to which live web services are vulnerable to ReDoS.

In this paper, we conduct the first black-box …

Discrepancies Among Pre-Trained Deep Neural Networks: A New Threat To Model Zoo Reliability, Diego Montes, Pongpatapee Peerapatanapokin, Jeff Schultz, Chengjun Guo, Wenxin Jiang, James C. Davis

Department of Electrical and Computer Engineering Faculty Publications

Training deep neural networks (DNNs) takes significant time and resources. A practice for expedited deployment is to use pre-trained deep neural networks (PTNNs), often from model zoos.collections of PTNNs; yet, the reliability of model zoos remains unexamined. In the absence of an industry standard for the implementation and performance of PTNNs, engineers cannot confidently incorporate them into production systems. As a first step, discovering potential discrepancies between PTNNs across model zoos would reveal a threat to model zoo reliability. Prior works indicated existing variances in deep learning systems in terms of accuracy. However, broader measures of reliability for PTNNs from …

An Empirical Study On The Impact Of Deep Parameters On Mobile App Energy Usage, Qiang Xu, James C. Davis, Y Charlie Hu, Abhilash Jindal

Department of Electrical and Computer Engineering Faculty Publications

Improving software performance through configuration parameter tuning is a common activity during software maintenance. Beyond traditional performance metrics like latency, mobile app developers are interested in reducing app energy usage. Some mobile apps have centralized locations for parameter tuning, similar to databases and operating systems, but it is common for mobile apps to have hundreds of parameters scattered around the source code. The correlation between these "deep" parameters and app energy usage is unclear. Researchers have studied the energy effects of deep parameters in specific modules, but we lack a systematic understanding of the energy impact of mobile deep parameters. …

Modeling The Formation Of Efflorescence And Subflorescence Caused By Salt Solution Evaporation From Porous Media, Rishav Roy, Justin Weibel, Suresh V. Garimella

CTRC Research Publications

Understanding the dynamics of precipitation and crystallization as salt solutions evaporate from porous media is of importance in the context of preservation of historical monuments, understanding soil nutrient content, and design of porous evaporators for use in distillation plants. Transient advection-diffusion equations govern the salt mass fraction profile of the solution inside the porous medium. These governing equations are solved to obtain the solute mass fraction profile within the porous medium as well as the effloresced salt crust. Further accounting for precipitation allows a study of the formation and growth of efflorescence and subflorescence. Crystallization experiments are performed by allowing …

A Pressure And Temperature Cycling Test Stand With Hot-Gas Bypass Control For Evaluation Of Adhesive Joints In Hvac&R Applications, Haotian Liu, Justin Weibel, Patrick Geoghegan, Eckhard A. Groll

CTRC Research Publications

The formation of joints is critical to the long-term reliability with leak-free operation of heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems. Leakages commonly occur due to fatigue failure developing in joined materials from continuous pressure and temperature cycling with mechanical vibration and refrigerant under pressure inside the system. In particular, rapid pressure and temperature changes happen frequently (e.g., multiple times per day) when the system is switched on and off. Therefore, it is important to have an automatically controlled fast- 2 response pressure and temperature cycling (PTC) test stand available to test the performance of refrigeration joints to evaluate …

Energy Savings Of Radiative Cooling Paints Applied To Residential Buildings, J. Peoples, Y.-W. Hung, Z. Fang, J. Braun, W. T. Horton, X. Ruan

CTRC Research Publications

No abstract provided.

Towards Quieter Air-Cooling Systems: Rotor Self-Noise Prediction For Axial Cooling Fans, W. Zhao, S. Wasala, T. Persoons

CTRC Research Publications

No abstract provided.

Updated Performance And Operating Characteristics Of A Novel Rotating Spool Compressor, Joe Orosz, Greg Kemp, Craig Bradshaw, Eckhard Groll

International Compressor Engineering Conference

No abstract provided.

Simultaneous Measurement Of Temperature And Strain In Electronic Packages Using Multi-Frame Super-Resolution Infrared Thermography And Digital Image Correlation, Sara K. Lyons, Justin Weibel, Suresh V. Garimella

CTRC Research Publications

For microelectronic components and systems, reliability under thermomechanical stress is of critical importance. Experimental characterization of hotspots and temperature gradients, which can lead to deformation in the component, relies on accurate mapping of the surface temperature. One method of non-invasively acquiring this data is through infrared (IR) thermography. However, IR thermography is often limited by the typically low resolution of such cameras. Additionally, the unique surface finish preparations required to infer physical deformation using digital image correlation (DIC) generally interferes with the ability to measure the temperature with IR thermography, which prefers a uniform high emissivity. This work introduces a …

3d Conjugate Heat Transfer Modelling Of E-Compressor, Abhishek Ballani, Mingyuan Tao, Chiranth Srinivasan, Haiyang Gao, Dipak Maiti, Sujan Dhar

International Compressor Engineering Conference

No abstract provided.

Numerical And Experimental Investigation Of The Cylinder Inlet Temperatures For Different Designs Of The Suction Line Of A Hermetic Reciprocating Compressor, Julian Gräf, Jan Tuhovcak, Ricardo Brancher

International Compressor Engineering Conference

No abstract provided.

Evaluation And Quantification Of Semi-Empirical Compressor Model Predictive Capabilities Under Modulation And Extrapolation Scenarios, Kalen Steve Gabel, Craig R. Bradshaw

International Compressor Engineering Conference

No abstract provided.

Suction Valve Design Optimization To Improve Reliability, Sehnaz Ektas, Haluk Arda Avci

International Compressor Engineering Conference

No abstract provided.

Semi-Empirical Scroll Compressor Model With Optional Vapor-Injection, Jan Christ, Fabian Schmid, Konstantinos Stergiaropoulos, Stefan Bertsch

International Compressor Engineering Conference

No abstract provided.