Engineering Commons^™

Comparison Of New Metrics For Assessment Of Risks Of Occupational Noise, Wisam Al-Dayyeni, Jun Qin

ASA Multidisciplinary Research Symposium

The acoustic environment nowadays is filled with excessive noise sources. Here, we will compare the conventional noise metrics(A-weighting and C-weighting) with our two developed advanced models (the adaptive weighting (F-weight) and the complex velocity level (CVL) auditory fatigue model).

Soft Elastomeric Capacitor Network For Strain Sensing Over Large Surfaces, Simon Laflamme, Husaam S. Saleem, Bharath K. Vasan, Randall L. Geiger, Degang J. Chen, Michael R. Kessler, Krishna Rajan

Randall Geiger

Field applications of existing sensing solutions to structural health monitoring (SHM) of civil structures are limited. This is due to economical and/or technical challenges in deploying existing sensing solutions to monitor geometrically large systems. To realize the full potential of SHM solutions, it is imperative to develop scalable cost-effective sensing strategies. We present a novel sensor network specifically designed for strain sensing over large surfaces. The network consists of soft elastomeric capacitors (SECs) deployed in an array form. Each SEC acts as a surface strain gage transducing local strain into changes in capacitance. Results show that the sensor network can …

Large-Scale Flexible Membrane For Automatic Strain Monitoring Of Transportation Infrastructure, Simon Laflamme, Venkata D. Kolipara, Hussam S. Saleem, Randall L. Geiger

Randall Geiger

Structural Health Monitoring (SHM) of transportation infrastructures is a complex task, typically conducted by visual inspection due to the technical and economical constrains of existing health monitoring technologies. It results that health monitoring is highly dependent on scheduling and on the judgment of the inspectors, which can be costly and ineffective. Thus, it is fundamental to automate the SHM process to allow timely inspection, maintenance, and management of transportation infrastructure. The authors propose a flexible membrane that can be deployed over large surfaces, at low cost, for automatic and continuous monitoring of strains. The membrane, termed sensing skin, is constituted …

Non-Linear Inverse Analysis Of Transportation Structures Using Neuro-Adaptive Networks With Hybrid Learning Algorithm, Kasthurirangan Gopalakrishnan, Siddhartha K. Khaitan, Halil Ceylan

Siddhartha Khaitan

The load-bearing capacity of pavement structures is a fundamental structural performance metric of transportation infrastructure networks in the context of safe and efficient movement of people and goods from one place to another. Non-destructive test (NDT) methods are typically employed to routinely evaluate the structural condition of pavement structures, their lifespan and the appropriate maintenance activities to be carried out. This involves computing the Young’s modulus of each layer of the pavement structure through inverse analysis of acquired NDT data. Over the past two decades, soft computing techniques such as Artificial Neural Networks (ANNs), Genetic Algorithms (GAs), and Fuzzy Logic …

Prediction Of Remaining Life Of Power Transformers Based On Left Truncated And Right Censored Lifetime Data, Yili Hong, William Q. Meeker, James D. Mccalley

James McCalley

Prediction of the remaining life of high-voltage power transformers is an important issue for energy companies because of the need for planning maintenance and capital expenditures. Lifetime data for such transformers are complicated because transformer lifetimes can extend over many decades and transformer designs and manufacturing practices have evolved. We were asked to develop statistically-based predictions for the lifetimes of an energy company’s fleet of high-voltage transmission and distribution transformers. The company’s data records begin in 1980, providing information on installation and failure dates of transformers. Although the dataset contains many units that were installed before 1980, there is no …

Elastometric Device For Tunable Imaging, Jaeyoun Kim

Jaeyoun Kim

An optical micro-electro-mechanical systems (MEMS) structure is provided. The structure includes an elastomer membrane, a plurality of polymer fibers attached to the elastomer membrane, an array of detectors operatively connected to the plurality of polymer fibers at a first end of the plurality of polymer fibers, and a microlens array operatively connected to the plurality of polymer fibers at a second end of the plurality of polymer fibers. A method of manufacturing an optical MEMS structure is provided. The method includes forming a hollow PDMS chamber in which PDMS fibers extend from top to bottom using a lost wax molding …

Highly Directional Receiver And Source Antennas Using Photonic Band Gap Crystals, Rana Biswas, Gary L. Tuttle, Ekmel Ozbay, Burak Temelkuran, Mihail Sigalas, Kai-Ming Ho

Gary Tuttle

A directional antenna made with photonic band gap structures has been presented. The directional antenna is formed with two photonic band gap structures oriented back to back and separated from each other by a distance to form a resonant cavity between the photonic band gap structures. An antenna element is placed in the resonant cavity. The resonant frequency of the cavity is tuned by adjusting the distance between the photonic band gap structures. The resonant cavity can be asymmetrical or symmetrical.

Weak Anti-Localization And Quantum Oscillations Of Surface States In Topological Insulator Bi2se2te, Lihong Bao, Liang He, Nicholas R. Meyer, Xufeng Kou, Peng Zhang, Zhi-Gang Chen, Alexei V. Fedorov, Trevor M. Riedemann, Thomas A. Lograsso, Kang L. Wang, Gary Tuttle, Faxian Xiu

Gary Tuttle

Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. Here, we report the observation of weak anti-localization and quantum oscillations originated from surface states in Bi2Se2Te crystals. Angle-resolved photoemission spectroscopy measurements on cleaved Bi2Se2Te crystals show a well-defined linear dispersion without intersection of the conduction band. The measured weak anti-localization effect agrees well with the Hikami-Larkin-Nagaoka model and the extracted phase coherent length shows a power-law dependence with temperature ( ∼T^−0.44), indicating the presence of the surface states. …

Network Connection Blocker, Method, And Computer Readable Memory For Monitoring Connections In A Computer Network And Blocking The Unwanted Connections, Douglas W. Jacobson, James A. Davis

Douglas Jacobson

A network connection blocker for monitoring connections between host computers in a network and blocking the unwanted connections. The host computers transmit connection packets between each other in accordance with a network protocol suite when seeking to establish, providing network services with, and close the connections. The network protocol suite includes a connection oriented transport layer protocol. The network connection blocker comprises a network interface that receives the connection packets transmitted between the host computers. It also comprises a blocking module that processes the received connection packets to detect the unwanted connections. The blocking module then generates connection packets in …

Smart Sensing Skin For Detection And Localization Of Fatigue Cracks, Sari Kharroub, Simon Laflamme, Chunhui Song, Daji Qiao, Brent M. Phares, Jian Li

Daji Qiao

Fatigue cracks on steel components may have strong consequences on the structure's serviceability and strength. Their detection and localization is a difficult task. Existing technologies enabling structural health monitoring have a complex link signal-to-damage or have economic barriers impeding large-scale deployment. A solution is to develop sensing methods that are inexpensive, scalable, with signals that can directly relate to damage. The authors have recently proposed a smart sensing skin for structural health monitoring applications to mesosystems. The sensor is a thin film soft elastomeric capacitor (SEC) that transduces strain into a measurable change in capacitance. Arranged in a network configuration, …

Integration Of A Prototype Wireless Communication System With Micro-Electromechanical Temperature And Humidity Sensor For Concrete Pavement Health Monitoring, Shuo Yang, Keyan Shen, Halil Ceylan, Sunghwan Kim, Daji Qiao, Kasthurirangan Gopalakrishnan

Daji Qiao

In recent years, structural health monitoring and management (SHMM) has become a popular approach and is considered essential for achieving well-performing, long-lasting, sustainable transportation infrastructure systems. Key requirements in ideal SHMM of road infrastructure include long-term, continuous, and real-time monitoring of pavement response and performance under various pavement geometry-materials-loading configurations and environmental conditions. With advancements in wireless technologies, integration of wireless communications into sensing device is considered an alternate and superior solution to existing time- and labor-intensive wired sensing systems in meeting the requirements of an ideal SHMM. This study explored the development and integration of a wireless communications sub-system …

Design And Operation Of Distribution Markets, Sina Parhizi

Electronic Theses and Dissertations

The growing penetration of distributed prosumers especially microgrids poses new challenges to the operation of wholesale markets and distribution power systems. Price spikes and higher uncertainty are among these consequences. Distribution markets are envisioned as a remedy to streamline integration of distributed resources and microgrids in the electricity market. This dissertation offers an analytical formulation of electricity markets in the distribution level, considering various prevailing aspects of the market operation problem.

The prevailing challenges in regards to integration of microgrids in the electricity markets are illustrated first, and the distribution market operator (DMO) construct is outlined. The day-ahead scheduling of …

Optimized Trajectory Generation For Car-Like Robots On A Closed Loop Track, Tyler Friedl

Electronic Theses and Dissertations

This thesis presents a method for generating an optimized path through a given track. The path is generated by choosing waypoints throughout the track then iteratively optimizing the position of these waypoints. The waypoints are then connected by optimized paths represented by curvature polynomials. The end result is a path through the track represented as a spline of curvature polynomials. This method is applied to multiple simulated tracks and the results are presented. By generating and representing the paths in the continuous domain, the method has improved computational efficiency from many of the discrete methods used to generate an optimal …

System Identification Of A Circulation Control Unmanned Aerial Vehicle, Mohammed Agha

Electronic Theses and Dissertations

The advancement in automation and sensory systems in recent years has led to an increase the demand of UAV missions. Due to this increase in demand, the research community has gained interest in investigating UAV performance enhancing systems. Circulation Control (CC), which is an active control flow method used to enhance UAV lift, is a performance enhancing system currently studied. In prior research, experimental studies have shown that Circulation Control wings (CCW) implemented on class-I UAVs can reduce take-off distance by 54%. Wind tunnel tests reveal that CC improves aircraft payload capabilities through lift enhancement. Increasing aircraft payload capabilities causes …

Computer-Aided Cancer Diagnosis And Grading Via Sparse Directional Image Representations, Hadi Rezaeilouyeh

Electronic Theses and Dissertations

Prostate cancer and breast cancer are the second cause of death among cancers in males and females, respectively. If not diagnosed, prostate and breast cancers can spread and metastasize to other organs and bones and make it impossible for treatment. Hence, early diagnosis of cancer is vital for patient survival. Histopathological evaluation of the tissue is used for cancer diagnosis. The tissue is taken during biopsies and stained using hematoxylin and eosin (H&E) stain. Then a pathologist looks for abnormal changes in the tissue to diagnose and grade the cancer. This process can be time-consuming and subjective. A reliable and …

Effect Of Exponential Correlation Model On Spectral And Energy Efficiency For Massive Mimo Systems, Saleh Albdran

Electronic Theses and Dissertations

During the past few years, the number of wireless devices has been increasing rapidly. Wireless networks are serving and connecting billions of wireless devices where these devices are demanding higher data rate and lower latency to be able to support voice, video and gaming applications. Moreover, the consumed energy by the wireless systems will be increasing. Hence, the Fifth generation (5G) wireless networks needs to provide higher data rate, serve larger number of users simultaneously and be more energy efficient. One of the promising technologies that can meet the above requirements is Massive Multiple Input Multiple Output (MIMO). The main …

Optimal Capacity And Energy Efficiency Of Massive Mimo Systems, Ahmed Alshammari

Electronic Theses and Dissertations

A lot of effort has been made during the last two decades to study and apply the concepts of MIMO technology in most of the wireless standards. Therefore, a huge improvement in the performance of wireless communications has been made. However, Demand for wireless services has exponentially increased during the past ten years. Hence, high throughput is very important for all users to get the best experience with the offered services. This creates many technical challenges that are difficult to handle with the existing technology. Therefore, massive multiple input multiple output (massive MIMO) is a new technology that has been …

Data-Centric Situational Awareness And Management In Intelligent Power Systems, Xiaoxiao Dai

Electronic Theses and Dissertations

The rapid development of technology and society has made the current power system a much more complicated system than ever. The request for big data based situation awareness and management becomes urgent today. In this dissertation, to respond to the grand challenge, two data-centric power system situation awareness and management approaches are proposed to address the security problems in the transmission/distribution grids and social benefits augmentation problem at the distribution-customer lever, respectively.

To address the security problem in the transmission/distribution grids utilizing big data, the first approach provides a fault analysis solution based on characterization and analytics of the synchrophasor …

Risk Optimized Microgrid Resource Management, Thomas William Cashel Iii

Electronic Theses and Dissertations

This thesis proposes a risk based price adjustment method for a day ahead scheduling of a distribution side tiered community microgrid within a transactive energy style market. The system is organized into a master controller and local controller confïguration to simulate behind meter activity that is not visible to the master controller. Conditional value at risk is used to asses the risk of distributed energy resources in each local controller and the risk for each local controller is aggregated providing each local controller a single risk value. Each device's, or local controller's, risk value is used to adjust the price …