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Performance

2022

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Articles 1 - 19 of 19

Full-Text Articles in Engineering

Fastklee: Faster Symbolic Execution Via Reducing Redundant Bound Checking Of Type-Safe Pointers, Haoxin Tu, Lingxiao Jiang, Xuhua Ding, He Jiang Nov 2022

Fastklee: Faster Symbolic Execution Via Reducing Redundant Bound Checking Of Type-Safe Pointers, Haoxin Tu, Lingxiao Jiang, Xuhua Ding, He Jiang

Research Collection School Of Computing and Information Systems

Symbolic execution (SE) has been widely adopted for automatic program analysis and software testing. Many SE engines (e.g., KLEE or Angr) need to interpret certain Intermediate Representations (IR) of code during execution, which may be slow and costly. Although a plurality of studies proposed to accelerate SE, few of them consider optimizing the internal interpretation operations. In this paper, we propose FastKLEE, a faster SE engine that aims to speed up execution via reducing redundant bound checking of type-safe pointers during IR code interpretation. Specifically, in FastKLEE, a type inference system is first leveraged to classify pointer types (i.e., safe …


An Empirical Comparison Of The Security And Performance Characteristics Of Topology Formation Algorithms For Bitcoin Networks, Muntadher Sallal, Ruairí De Fréin, Ali Malik, Benjamin Aziz Sep 2022

An Empirical Comparison Of The Security And Performance Characteristics Of Topology Formation Algorithms For Bitcoin Networks, Muntadher Sallal, Ruairí De Fréin, Ali Malik, Benjamin Aziz

Articles

There is an increasing demand for digital crypto-currencies to be more secure and robust to meet the following business requirements: (1) low transaction fees and (2) the privacy of users. Nowadays, Bitcoin is gaining traction and wide adoption. Many well-known businesses have begun accepting bitcoins as a means of making financial payments. However, the susceptibility of Bitcoin networks to information propagation delay, increases the vulnerability to attack of the Bitcoin network, and decreases its throughput performance. This paper introduces and critically analyses new network clustering methods, named Locality Based Clustering (LBC), Ping Time Based Approach (PTBC), Super Node Based Clustering …


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 Dr., Ruchita Jani, Hongxi Yin Jul 2022

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 Dr., Ruchita Jani, Hongxi Yin

Conference papers

To provide energy-efficient space heating and cooling, a thermoelectric building envelope (TBE) embeds thermoelectric devices in building walls. The thermoelectric device in the building envelope can provide active heating and cooling without requiring refrigerant use and energy transport among subsystems. Thus, the TBE system is energy and environmentally friendly. A few studies experimentally investigated the TBE under limited operating conditions, and only simplified models for the commercial thermoelectric module (TEM) were developed to quantify its performance. A holistic approach to optimum system performance is needed for the optimal system design and operation. The study developed a holistic TBE-building system model …


Novel Test Fixture For Characterizing Mems Switch Microcontact Reliability And Performance, Protap Kumar Mahanta Jul 2022

Novel Test Fixture For Characterizing Mems Switch Microcontact Reliability And Performance, Protap Kumar Mahanta

Dissertations (1934 -)

Microelectromechanical systems (MEMS) switch is considered as a better alternative than the conventional solid-state DC and RF switches due to their low contact resistance approximately 1 Ω, near-zero power consumption approximately 0 W, low insertion loss approximately 0.2 dB, and high isolation approximately -30 dB. However, reliability is a great concern for them to be ubiquitously used by the industry for specific applications. Switching dynamics and microcontact surface physics play the critical role in determining their reliability. A simple, quick, and efficient test fixture is required to study the contact surface physics as well as to optimize the switching dynamics.In …


Numerical Study Of The Effects Of Injector Geometry On The Performance Of Rotating Detonation Engines, Xavier Roy Jul 2022

Numerical Study Of The Effects Of Injector Geometry On The Performance Of Rotating Detonation Engines, Xavier Roy

Theses and Dissertations

A study of the impact of injector geometry on the performance of rotating detonation engines is performed. A numerical scheme is developed to represent the rotating detonation engine physics. In order to simulate the interaction between the chamber and the injectors, a multizone capability is implemented inside the numerical tool. The model is calibrated to represent a hydrogen-air detonation. The rotating detonation engine annular chamber is unwrapped and studied as a two-dimensional planar domain with a periodic boundary condition. Several numerical experiments are conducted. In particular, injection parameters are examined, such as the injector inflow to channel area ratio, injection …


A Methodology For Observing The Deformation Of Rubber Studs When Stepping On A Stone, Robin Compeyron, Jürgen Mitternacht, Veit Senner, Bahador Keshvari, Valentin Wohlgut Jun 2022

A Methodology For Observing The Deformation Of Rubber Studs When Stepping On A Stone, Robin Compeyron, Jürgen Mitternacht, Veit Senner, Bahador Keshvari, Valentin Wohlgut

International Sports Engineering Association – Engineering of Sport

No abstract provided.


The Effect Of Bending And Torsional Stiffness On The Edge Grip Of An Alpine Ski, Jonas Truong, Philippe Gosselin, Alexis Lussier-Desbiens Jun 2022

The Effect Of Bending And Torsional Stiffness On The Edge Grip Of An Alpine Ski, Jonas Truong, Philippe Gosselin, Alexis Lussier-Desbiens

International Sports Engineering Association – Engineering of Sport

No abstract provided.


Early Life Benefits Of Hybrid Sports Turf, Paul Fleming, Lewis Darwin, Steph Forrester Jun 2022

Early Life Benefits Of Hybrid Sports Turf, Paul Fleming, Lewis Darwin, Steph Forrester

International Sports Engineering Association – Engineering of Sport

No abstract provided.


The Permeability And Performance Of Competition Swimsuits, Hannah Deboer Jun 2022

The Permeability And Performance Of Competition Swimsuits, Hannah Deboer

International Sports Engineering Association – Engineering of Sport

No abstract provided.


Comparative Study Of Snort 3 And Suricata Intrusion Detection Systems, Cole Hoover May 2022

Comparative Study Of Snort 3 And Suricata Intrusion Detection Systems, Cole Hoover

Computer Science and Computer Engineering Undergraduate Honors Theses

Network Intrusion Detection Systems (NIDS) are one layer of defense that can be used to protect a network from cyber-attacks. They monitor a network for any malicious activity and send alerts if suspicious traffic is detected. Two of the most common open-source NIDS are Snort and Suricata. Snort was first released in 1999 and became the industry standard. The one major drawback of Snort has been its single-threaded architecture. Because of this, Suricata was released in 2009 and uses a multithreaded architecture. Snort released Snort 3 last year with major improvements from earlier versions, including implementing a new multithreaded architecture …


Predictive Performance And Teaming Via The Mist-C Ocean Hierarchy Utilizing Personality And Skills, Brighton H. Owen May 2022

Predictive Performance And Teaming Via The Mist-C Ocean Hierarchy Utilizing Personality And Skills, Brighton H. Owen

All Theses

This thesis seeks to establish and define the individual, the team as an entity, and qualify various metrics to predict team performance. When several individuals come together, they form a team that is often capable of designing and developing concepts beyond the individual on their own by methods of task dispersion, goal orientation, communication, and more. With these teams comes growth and increased performance leading to more efficient processes and better metrics by which performance may be measured. To achieve this, 34 engineering students in the AerosPACE senior design program, which lasted two semesters, were asked to complete surveys in …


Disney During Covid-19: The Tourist And The Actor’S Nightmare, Jennifer A. Kokai, Tom Robson Apr 2022

Disney During Covid-19: The Tourist And The Actor’S Nightmare, Jennifer A. Kokai, Tom Robson

Journal of Themed Experience and Attractions Studies

In this essay, we argue that the experience of being at Disney theme parks in COVID times was a waking version of what is sometimes called “The Actor’s Nightmare.” Due to safety regulations, theme parks either dropped live entertainment that structures the day as a show with a clear beginning and end (e.g. park-opening rope drop performances, and the fireworks), attempted to include references to COVID in live entertainment (like in

the Frozen Ever After singalong, which added some COVID jokes), or to ignore it (like the Festival of the Lion King). In any case, due to these measures the …


Design And Construction Of A Biogas Burner, David O. Obada Mar 2022

Design And Construction Of A Biogas Burner, David O. Obada

Palestine Technical University Research Journal

This paper details the design and fabrication of a burner system, operating on biogas, for use in remote or rural regions of developing countries such as Nigeria. A desirable use for such a system in these areas is domestic cooking, and the burner has been designed with this need in mind, focusing on characteristics such as simplicity, cost effectiveness, efficiency and safety. Mild steel, brass and galvanized pipe sourced locally were selected for the construction. An empirical version of Bernoulli’s theorem was used to derive the flow rate of gas. The different components of the burner design were shown. Also …


Faster Multidimensional Data Queries On Infrastructure Monitoring Systems, Yinghua Qin, Gheorghi Guzun Feb 2022

Faster Multidimensional Data Queries On Infrastructure Monitoring Systems, Yinghua Qin, Gheorghi Guzun

Faculty Research, Scholarly, and Creative Activity

The analytics in online performance monitoring systems have often been limited due to the query performance of large scale multidimensional data. In this paper, we introduce a faster query approach using the bit-sliced index (BSI). Our study covers multidimensional grouping and preference top-k queries with the BSI, algorithms design, time complexity evaluation, and the query time comparison on a real-time production performance monitoring system. Our research work extended the BSI algorithms to cover attributes filtering and multidimensional grouping. We evaluated the query time with the single attribute, multiple attributes, feature filtering, and multidimensional grouping. To compare with the existing prior …


Challenges In Covid-19 Chest X-Ray Classification: Problematic Data Or Ineffective Approaches?, Muhammad Ridzuan, Ameera Ali Bawazir, Ivo Gollini Navarrete, Ibrahim Almakky, Mohammad Yaqub Jan 2022

Challenges In Covid-19 Chest X-Ray Classification: Problematic Data Or Ineffective Approaches?, Muhammad Ridzuan, Ameera Ali Bawazir, Ivo Gollini Navarrete, Ibrahim Almakky, Mohammad Yaqub

Computer Vision Faculty Publications

The value of quick, accurate, and confident diagnoses cannot be undermined to mitigate the effects of COVID-19 infection, particularly for severe cases. Enormous effort has been put towards developing deep learning methods to classify and detect COVID-19 infections from chest radiography images. However, recently some questions have been raised surrounding the clinical viability and effectiveness of such methods. In this work, we carry out extensive experiments on a large COVID-19 chest X-ray dataset to investigate the challenges faced with creating reliable solutions from both the data and machine learning perspectives. Accordingly, we offer an in-depth discussion into the challenges faced …


Is Contrastive Learning Suitable For Left Ventricular Segmentation In Echocardiographic Images?, Mohamed Saeed, Rand Muhtaseb, Mohammad Yaqub Jan 2022

Is Contrastive Learning Suitable For Left Ventricular Segmentation In Echocardiographic Images?, Mohamed Saeed, Rand Muhtaseb, Mohammad Yaqub

Computer Vision Faculty Publications

Contrastive learning has proven useful in many applications where access to labelled data is limited. The lack of annotated data is particularly problematic in medical image segmenta-tion as it is difficult to have clinical experts manually annotate large volumes of data. One such task is the segmentation of cardiac structures in ultrasound images of the heart. In this paper, we argue whether or not contrastive pretraining is helpful for the segmentation of the left ventricle in echocardiography images. Furthermore, we study the effect of this on two segmentation networks, DeepLabV3, as well as the commonly used segmentation net-work, UNet. Our …


Development And Verification Of Flight Data Informed Performance Estimation And Prediction Simulation Tool For Small Electrical Multi-Rotor Uav, Nicholas Scott Borelle Jan 2022

Development And Verification Of Flight Data Informed Performance Estimation And Prediction Simulation Tool For Small Electrical Multi-Rotor Uav, Nicholas Scott Borelle

Graduate Theses, Dissertations, and Problem Reports

While small scale multi-rotor aircraft are becoming an increasingly large market with applications emerging every day, their ability to have both a high endurance/long range and a high speed/performance flight is severely limited. This leads to uncertainty in mission planning and aircraft design, specifically when deciding mission length and available on-board energy. Uncertainty like this leads to an increased chance of failure to complete the mission, and a failure to recover the aircraft. Considering that these aircraft are used by everyone from hobbyists to commercial companies to military personnel, the applications and missions being flown carry importance and a serious …


Performance Of Sensor Fusion For Vehicular Applications, Nikola Janevski Jan 2022

Performance Of Sensor Fusion For Vehicular Applications, Nikola Janevski

Graduate Theses, Dissertations, and Problem Reports

Sensor fusion is a key system in Advanced Driver Assistance Systems, ADAS. The perfor-
mance of the sensor fusion depends on many factors such as the sensors used, the kinematic
model used in the Extended Kalman Filter, EKF, the motion of the vehicles, the type of
road, the density of vehicles, and the gating methods. The interactions between parameters
and the extent to which individual parameters contribute to the overall accuracy of a sensor
fusion system can be difficult to assess.
In this study, a full-factorial experimental evaluation of a sensor fusion system based
on a real vehicle was performed. …


Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo Jan 2022

Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo

Department of Information Systems & Computer Science Faculty Publications

Pair programming is a model of collaborative learning. It has become a well-known pedagogical practice in teaching introductory programming courses because of its potential benefits to students. This study aims to investigate pair patterns in the context of pair program tracing and debugging to determine what characterizes collaboration and how these patterns relate to success, where success is measured in terms of performance task scores. This research used eye-tracking methodologies and techniques such as cross-recurrence quantification analysis. The potential indicators for pair success were used to create a model for predicting pair success. Findings suggest that it is possible to …