Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

129737 Full-Text Articles 145061 Authors 43465233 Downloads 269 Institutions

All Articles in Engineering

Faceted Search

129737 full-text articles. Page 3553 of 3584.

Ss-Dna Functionalized Ultra-Thin-Film Aln Contour-Mode Resonators With Self-Sustained Oscillator For Volatile Organic Chemical Detection, Matteo Rinaldi, Brandon Duick, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza 2010 University of Pennsylvania

Ss-Dna Functionalized Ultra-Thin-Film Aln Contour-Mode Resonators With Self-Sustained Oscillator For Volatile Organic Chemical Detection, Matteo Rinaldi, Brandon Duick, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza

Departmental Papers (ESE)

This paper reports on the design and experimental verification of a new class of nanoscale gravimetric sensors based on ultra-thin-film AlN Contour-Mode Resonant Sensor (CMR-S) functionalized with ss-DNA and connected to a chip-based self-sustaining oscillator loop (fabricated in the ON Semiconductor 0.5 μm CMOS process) for direct frequency read-out. The 220 MHz oscillator based on the ultra-thin AlN CMR-S exhibits an Allan Variance of ∼20 Hz for 100 ms gate time. The sensor affinity for the adsorption of volatile organic chemicals such as 2,6 dinitroluene (DNT, a simulant for explosive vapors) is enhanced by functionalizing the top gold ...


1.05-Ghz Cmos Oscillator Based On Lateral-Field-Excited Piezoelectric Aln Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van der Spiegel, Gianluca Piazza 2010 University of Pennsylvania

1.05-Ghz Cmos Oscillator Based On Lateral-Field-Excited Piezoelectric Aln Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van Der Spiegel, Gianluca Piazza

Departmental Papers (ESE)

This paper reports on the first demonstration of a 1.05-GHz microelectromechanical (MEMS) oscillator based on lateral-field-excited (LFE) piezoelectric AlN contour-mode resonators. The oscillator shows a phase noise level of −81 dBc/Hz at 1-kHz offset frequency and a phase noise floor of −146 dBc/Hz, which satisfies the global system for mobile communications (GSM) requirements for ultra-high frequency (UHF) local oscillators (LO). The circuit was fabricated in the AMI semiconductor (AMIS) 0.5-μm complementary metal-oxide-semiconductor (CMOS) process, with the oscillator core consuming only 3.5 mW DC power. The device overall performance has the best figure-of-merit (FoM) when compared ...


1.5-Ghz Cmos Voltage-Controlled Oscillator Based On Thickness-Field-Excited Piezoelectric A1n Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van der Spiegel, Gianluca Piazza 2010 University of Pennsylvania

1.5-Ghz Cmos Voltage-Controlled Oscillator Based On Thickness-Field-Excited Piezoelectric A1n Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van Der Spiegel, Gianluca Piazza

Departmental Papers (ESE)

This paper reports on the first demonstration of the 1.5 GHz CMOS oscillator based on thickness-field-excited (TFE) piezoelectric AIN MEMS contour-mode resonators (CMRs). The measured phase noise is -85 dBc/Hz at 10 kHz offset frequency and -151 dBc/Hz at 1MHz. This is the highest frequency MEMS oscillator ever reported using a laterally vibrating mechanical resonator. The high frequency operation has been enabled by optimizing the geometrical design and micro-fabrication process of TFE AIN CMRs, so that a low effective motional resistance around 50 Ω is achieved together with a high unloaded quality factor (Qu) approaching 2500 ...


Transportation For Liveable Cities: Problems, Obstacles, And Successful Solutions, Vukan R. Vuchic 2010 University of Pennsylvania

Transportation For Liveable Cities: Problems, Obstacles, And Successful Solutions, Vukan R. Vuchic

Departmental Papers (ESE)

This chapter focuses on urban transportation. It is written by the moderator of the session on Land Transportation. He asked the five speakers to report on positive achievements and challenges in their cities or countries. The chapter starts with the moderator's review of developments and trends in urban transportation and a summary of the five reports by participants presented in the session. It is followed by a brief review of the conditions in urban transportation and its impact on cities. Following a review of problems most cities face and mistakes in transportation planning many cities continue to make, this ...


Multiscale Investigation Of Random Heterogenous Media In Materials And Earth Sciences, Andrew J. Goupee 2010 The University of Maine

Multiscale Investigation Of Random Heterogenous Media In Materials And Earth Sciences, Andrew J. Goupee

Electronic Theses and Dissertations

This dissertation is concerned with three major areas pertaining to the characterization and analysis of heterogeneous materials. The first is focused on the modeling of heterogeneous materials with random microstructure and understanding their thermomechanical properties as well as developing a methodology for the multiscale thermoelastic analysis of random heterogeneous materials. Realistic random microstructures are generated for computational analyses using random morphology description functions. The simulated microstructures closely resemble actual micrographs of random heterogeneous materials. The simulated random microstructures are characterized using statistical techniques and their homogenized material properties computed using the asymptotic expansion homogenization method. The failure response of random ...


Hydrologic Variability And Change In The New England Region, Usa, Avirup Sen Gupta 2010 University of Maine - Main

Hydrologic Variability And Change In The New England Region, Usa, Avirup Sen Gupta

Electronic Theses and Dissertations

Traditional water resources management aims to ensure the steady and reliable water supply for human uses and maximize the economic benefits by dampening natural flow variability. However, such management practices essentially changes the flow regime in many ways and ecological degradation is one of the obvious consequences of that. Natural functioning and productivity of the native species require enough water flow in the streams and lake levels with sufficient quality. Thus, to protect the natural ecosystem diversity, sustainable water allocation policies have been developed and employed by many societies around the world. "Chapter 587: In-stream Flow and Lake and Pond ...


Assessment Of Benthic Flux Of Dissolved Organic Carbon In Estuaries Using The Eddy Correlation Technique, Michael P. Swett 2010 University of Maine - Main

Assessment Of Benthic Flux Of Dissolved Organic Carbon In Estuaries Using The Eddy Correlation Technique, Michael P. Swett

Electronic Theses and Dissertations

Dissolved organic carbon (DOC) is a water quality concern in estuarine environments, as DOC facilitates mobilization of metals and organics in sediments and leads to toxic disinfection byproducts during water treatment. Export of DOC from sediments can vary with changing environmental conditions, including wetland restoration and rising sea levels. Therefore, it is important to quantify flux of DOC across the sediment-water interface (SWI). Existing DOC flux measurement techniques, such as equilibrium dialysis, porewater extraction, and benthic chamber measurement, are intrusive to the sediment environment and underestimate flux by only capturing certain flux contributions. In this research, methods for estimating benthic ...


Casing Pipe Damage Detection With Optical Fiber Sensors: A Case Study In Oil Well Constructions, Zhi Zhou, Jianping He, Minghua Huang, Jun He, Genda Chen 2010 Missouri University of Science and Technology

Casing Pipe Damage Detection With Optical Fiber Sensors: A Case Study In Oil Well Constructions, Zhi Zhou, Jianping He, Minghua Huang, Jun He, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Casing pipes in oil well constructions may suddenly buckle inward as their inside and outside hydrostatic pressure difference increases. For the safety of construction workers and the steady development of oil industries, it is critically important to measure the stress state of a casing pipe. This study develops a rugged, real-time monitoring, and warning system that combines the distributed Brillouin Scattering Time Domain Reflectometry (BOTDR) and the discrete fiber Bragg grating (FBG) measurement. The BOTDR optical fiber sensors were embedded with no optical fiber splice joints in a fiber-reinforced polymer (FRP) rebar and the FBG sensors were wrapped in epoxy ...


Bridge Lessons Learned From The Wenchuan China, Earthquake, W. Phillip Yen, Genda Chen, Mark Yashinski, Youssef M. A. Hashash, Curtis J. Holub, Kehai Wang, Xiaodong Guo 2010 Missouri University of Science and Technology

Bridge Lessons Learned From The Wenchuan China, Earthquake, W. Phillip Yen, Genda Chen, Mark Yashinski, Youssef M. A. Hashash, Curtis J. Holub, Kehai Wang, Xiaodong Guo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A strong earthquake of M7.9 occurred in Wenchuan County in Sichuan Province, China, on May 12, 2008. This paper presents the field observations on various types of bridge damages, including unseating of girders, longitudinal and transverse offset of decks, pounding at expansion joints, shear key failure, bearing displacement, column shear, and flexible cracks. Plausible causes of damages and collapses are discussed and the lessons learned from this event are briefly summarized. Some of the postearthquake temporary constructions are also reported.


Condition Assessment Of Bill Emerson Memorial Cable-Stayed Bridge Under Postulated Design Earthquake, Dongming Yan, Wenjian Wang, Genda Chen, Bryan A. Hartnagel 2010 Missouri University of Science and Technology

Condition Assessment Of Bill Emerson Memorial Cable-Stayed Bridge Under Postulated Design Earthquake, Dongming Yan, Wenjian Wang, Genda Chen, Bryan A. Hartnagel

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, a three-dimensional finite element model of the Bill Emerson Memorial cable-stayed bridge was developed and validated with the acceleration data recorded during the M4.1 earthquake of May 1, 2005, in Manila, Arkansas. The model took into account the geometric nonlinear properties associated with cable sagging and soil-foundation-structure interaction. The validated model was used to evaluate the performance of a seismic protective system, the behavior of cable-stayed spans, and the accuracy of two simplified bridge models that have been extensively used by the structural control community. The calculated natural frequencies and mode shapes correlated well with the ...


Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. McDaniel, Michael A. Brower, David Pommerenke 2010 Missouri University of Science and Technology

Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. Mcdaniel, Michael A. Brower, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The working mechanism and the measurement principle of topology-based crack sensors made of coaxial cables are briefly reviewed. The sensitivity, spatial resolution, and ruggedness of two coaxial cable sensors, respectively made of rubber and Teflon dielectric materials, were compared and validated with laboratory testing of a 4/5-scale, T-shaped, reinforced concrete beam-column specimen. Two Teflon sensors were installed on one of the solid decks of a three-span continuous highway bridge to investigate their durability and measurement repeatability. Laboratory tests indicated that both types of sensors have high sensitivity, but the Teflon sensor has a higher spatial resolution and a negligible ...


Engineering Education Collaboration: Innovative Pedagogical Methods For High School And University Environmentalists, Leslie Hadaway, Megan Urbaitis, Regina Lamendella, Daniel B. Oerther, Andrea C. Burrows, Mike Borowczak, Anant R. Kukreti 2010 Missouri University of Science and Technology

Engineering Education Collaboration: Innovative Pedagogical Methods For High School And University Environmentalists, Leslie Hadaway, Megan Urbaitis, Regina Lamendella, Daniel B. Oerther, Andrea C. Burrows, Mike Borowczak, Anant R. Kukreti

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents an innovative teaching approach, how it is implemented, student response results of the implementation, and the assessment of impact on student learning. The findings are based on surveys given to the students after each lab lesson taught in partnership with university (Project STEP) and community members. The purpose of this paper is to showcase authentic molecular technology research methods that have been incorporated into a high school level water quality study in cooperation with a watershed restoration program. Typically, water quality studies focus on chemical analysis such as pH, dissolved oxygen, biochemical oxygen demand, orthophosphates, nitrates, temperature ...


Defending Privacy: The Development And Deployment Of A Darknet, Conor McManamon, Fredrick Mtenzi 2010 Dublin Institute of Technology

Defending Privacy: The Development And Deployment Of A Darknet, Conor Mcmanamon, Fredrick Mtenzi

Conference papers

New measures imposed by governments, Internet service providers and other third parties which threaten the state of privacy are also opening new avenues to protecting it. The unwarranted scrutiny of legitimate services such as file hosters and the BitTorrent protocol, once relatively unknown to the casual Internet user, is becoming more obvious. The darknet is a rising contender against these new measures and will preserve the default right to privacy of Internet users. A darknet is defined in the context of file sharing as a network which operates on top of another network such as the Internet for the purpose ...


Navigating The Corridors Of Power : Using Rfid And Compass Sensors For Robot Localisation And Navigation, Yan Lee, Brian Mac Namee, John Kelleher 2010 Dublin Institute of Technology

Navigating The Corridors Of Power : Using Rfid And Compass Sensors For Robot Localisation And Navigation, Yan Lee, Brian Mac Namee, John Kelleher

Conference papers

Localisation and navigation are still of the most important issues in mobile robotics. In certain indoor application scenarios Radio frequency identification (RFID) based absolute localisation has been found to be especially successful in supporting navigation. In this paper we examine the feasibility of an RFID and compass based approach to robot localisation and navigation for indoor environments that are dominated by corridors. We present a proof of concept system and show how it can be used to localized within and navigate through an environment.


Helmsman, Set A Course : Using A Compass And Rfid Tags For Indoor Localisation And Navigation, Yan Li, Brian Mac Namee, John Kelleher 2010 Dublin Institute of Technology

Helmsman, Set A Course : Using A Compass And Rfid Tags For Indoor Localisation And Navigation, Yan Li, Brian Mac Namee, John Kelleher

Conference papers

Localisation and navigation are still two of the most important issues in mobile robotics. In certain indoor application scenarios RFID (radio frequency identification)-based absolute localisation has been found to be especially successful in supporting navigation. In this paper we evaluate the feasibility of an RFID and compass based approach to robot localisation and navigation for indoor environments that are dominated by corridors. We describe our system and evaluate its performance in a small, but full-scale, test environment.


Design And Evaluation Of An Audio-Frequency Transresistance Amplifier For Magnetic Tape Playback, Thomas R. Salvatierra 2010 Wright State University

Design And Evaluation Of An Audio-Frequency Transresistance Amplifier For Magnetic Tape Playback, Thomas R. Salvatierra

Browse all Theses and Dissertations

Analog magnetic tape remains a medium of choice for high-fidelity sound recording and reproduction. Some of this fidelity is sacrificed during the tape playback process; an optimized playback preamplifier is therefore critical to the performance of the medium. Existing playback methods integrate the voltage generated across the reproduce head to obtain a signal directly proportional to the remanent magnetic flux of the tape. An alternate playback method proposes the use of a transresistance amplifier to convert flux-proportional reproduce head current directly to voltage. This eliminates the need for voltage integration and minimizes the amount of equalization performed upon playback. Circuit ...


Electromagnetic Fields, Power Losses, And Resistance Of High-Frequency Magnetic Devices, Daniel Joseph Whitman 2010 Wright State University

Electromagnetic Fields, Power Losses, And Resistance Of High-Frequency Magnetic Devices, Daniel Joseph Whitman

Browse all Theses and Dissertations

The operation of dc-dc PWM converters requires magnetic components that operate at high frequencies and carry large currents. At such frequencies the skin and proximity effects cause a substantial increase in power losses and ac resistance. This thesis reviews existing one dimensional analytical work on the prediction of these losses and, beginning with an inductor, derives expressions for the electromagnetic fields and power losses within the winding as well as the ac resistance of the device. The results of the inductor analysis are then extended to examine these quantities in transformers of various winding configurations. It is shown that proximity ...


The Gas Team And Nasa (Aka Boil, Boil, Toil And Trouble), Get Away Special Team 2010 2010 Utah State University

The Gas Team And Nasa (Aka Boil, Boil, Toil And Trouble), Get Away Special Team 2010

Education and Outreach

No abstract provided.


Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett 2010 Utah State University

Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett

Presentations

No abstract provided.


Turbidity Effects On Solar Radiation Attenuation And Reflection, Andrew Hobson 2010 Utah State University

Turbidity Effects On Solar Radiation Attenuation And Reflection, Andrew Hobson

Browse All Undergraduate research

Limited water resources in Southern Utah with the competing interests of humans and native fishes require careful management. High instream temperatures resulting from low flows are a consideration in managing the Virgin River for two endangered fish species. Throughout these periods, fish behavior changes have been observed during those high turbidity. One hypothesis was that high turbidity decreased the amount of solar radiation in the water column due to increased reflection at the water surface resulting in reduced instream temperatures. To quantify the extent of changes in incoming energy to the river, a water tank was constructed to measure the ...


Digital Commons powered by bepress