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An Experimental Study On Static And Dynamic Strain Sensitivity Of Smart Concrete Sensors Doped With Carbon Nanotubes For Shm Of Large Structures, Andrea Meoni, Antonella D'Alessandro, Austin Downey, Enrique García-Macías, Marco Rallini, A. Luigi Materazzi, Luigi Torre, Simon Laflamme, Rafael Castro-Triguero, Filippo Ubertini 2018 University of Perugia

An Experimental Study On Static And Dynamic Strain Sensitivity Of Smart Concrete Sensors Doped With Carbon Nanotubes For Shm Of Large Structures, Andrea Meoni, Antonella D'Alessandro, Austin Downey, Enrique García-Macías, Marco Rallini, A. Luigi Materazzi, Luigi Torre, Simon Laflamme, Rafael Castro-Triguero, Filippo Ubertini

Civil, Construction and Environmental Engineering Publications

The availability of new self-sensing cement-based strain sensors allows the development of dense sensor networks for Structural Health Monitoring (SHM) of reinforced concrete structures. These sensors are fabricated by doping cement-matrix materials with conductive fillers, such as Multi Walled Carbon Nanotubes (MWCNTs), and can be embedded into structural elements made of reinforced concrete prior to casting. The strain sensing principle is based on the multifunctional composites outputting a measurable change in their electrical properties when subjected to a deformation. Previous work by the authors was devoted to material fabrication, modeling and applications in SHM. In this paper, we investigate the ...


Base Pressure Control Using Micro-Jets In Supersonic Flow Regimes, Vigneshvaran Sethuraman, Sher Afghan Khan 2018 Monash University Malaysia

Base Pressure Control Using Micro-Jets In Supersonic Flow Regimes, Vigneshvaran Sethuraman, Sher Afghan Khan

International Journal of Aviation, Aeronautics, and Aerospace

Base pressure plays a vital role in aerospace-related applications and its control is essential in reduction of drag and improving fuel consumption. Low pressure at the base of Rockets, Missiles, bombs and shells are a very common problem happening at transonic and supersonic speeds. In most of the cases there is a significant dip in pressure at the base region which will have implications on the design of aerospace vehicles. This paper presents an experimental investigation carried out for flow control at supersonic regimes. Experiments were conducted to measure the base pressure in the base region and wall pressure distribution ...


Organizational Best Practices For Transportation Projects Delivered Using Alternative Contracting Methods, Douglas D. Gransberg, Carla Lopez del Puerto, Ricardo M. Tapia 2018 Iowa State University

Organizational Best Practices For Transportation Projects Delivered Using Alternative Contracting Methods, Douglas D. Gransberg, Carla Lopez Del Puerto, Ricardo M. Tapia

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

The use of Alternative Contracting Methods (ACM) to deliver US transportation projects has reached a point where a definitive set of best practices can be identified to leverage the lessons learned by early ACM adopters. The most pressing need is for guidance on how public agencies organize to implement ACMs in a budget-constrained environment where the possibility of increasing the number of public agency engineers is nil. This paper is based on mining the survey response data from 6 National Cooperative Highway Research Program (NCHRP) synthesis reports on ACM topics and proposes a framework for analyzing ACM practices deemed effective ...


Evaluation Of Route Changes Utilizing High-Resolution Gps Bus Transit Data, Travis Bradley Glick 2018 Portland State University

Evaluation Of Route Changes Utilizing High-Resolution Gps Bus Transit Data, Travis Bradley Glick

TREC Friday Seminar Series

Congestion and travel delay on urban roadways can influence operating costs and service attractiveness. This research uses high resolution bus data to examine sources of delay on urban arterials. A set of tools was created to help visualize trends in bus behavior and movement; this allowed larger traffic trends to be visualized along urban corridors and urban streets. By using buses as probes and examining aggregated bus behavior, contoured speed plots can be used to understand the behavior of roadways outside the zone of influence of bus stops. Speed plots can be utilized to discover trends and travel patterns with ...


An Open-Source Quadrature-Based Population Balance Solver For Openfoam, Alberto Passalacqua, Frédérique Laurent, Ehsan Madadi-Kandjani, Jeffrey C. Heylmun, Rodney O. Fox 2018 Iowa State University

An Open-Source Quadrature-Based Population Balance Solver For Openfoam, Alberto Passalacqua, Frédérique Laurent, Ehsan Madadi-Kandjani, Jeffrey C. Heylmun, Rodney O. Fox

Chemical and Biological Engineering Publications

The extended quadrature method of moments (EQMOM) for the solution of population balance equations (PBE) is implemented in the open-source computational fluid dynamic (CFD) toolbox OpenFOAM as part of the OpenQBMM project. The moment inversion procedure was designed (Nguyen et al., 2016) to maximize the number of conserved moments in the transported moment set. The algorithm is implemented in a general structure to allow the addition of other kernel density functions defined on R+, and arbitrary kernels to describe physical phenomena involved in the evolution of the number density function. The implementation is verified with a set of zero-dimensional cases ...


Portable Canopy Chamber Measurements Of Evapotranspiration In Corn, Soybean, And Reconstructed Prairie, Chenyi Luo, Zhuangji Wang, Thomas J. Sauer, Matthew J. Helmers, Robert Horton 2018 Iowa State University

Portable Canopy Chamber Measurements Of Evapotranspiration In Corn, Soybean, And Reconstructed Prairie, Chenyi Luo, Zhuangji Wang, Thomas J. Sauer, Matthew J. Helmers, Robert Horton

Agricultural and Biosystems Engineering Publications

Evapotranspiration (ET) is a vital component of a field water balance. Canopy chambers are a promising method for determining crop ET because they are portable and applicable at a relatively small plot (m2) scale. Although a variety of canopy chamber designs have been proposed, field tests are still necessary to evaluate chamber performance for measuring crop ET. The objectives of this study are (1) to construct and use an improved canopy chamber to measure ET of three crops [corn (Zea mays, L.), soybean (Glycine max), and reconstructed mixed prairie] and (2) to compare the canopy chamber measurements with flux tower ...


Magnetic Properties Of Gd Intermetallics, L. Petit, Z. Szotek, J. Jackson, M. Lüders, Durga Paudyal, Yaroslav Mudryk, Vitalij K. Pecharsky, K. A. Gschneidner, J. B. Staunton 2018 Daresbury Laboratory

Magnetic Properties Of Gd Intermetallics, L. Petit, Z. Szotek, J. Jackson, M. Lüders, Durga Paudyal, Yaroslav Mudryk, Vitalij K. Pecharsky, K. A. Gschneidner, J. B. Staunton

Ames Laboratory Accepted Manuscripts

Using first-principles calculations, based on disordered local moment theory, combined with the self-interaction corrected local spin density approximation, we study magnetic interactions in GdX intermetallics for X = Cu, Zn, Ga, Cd, and Mg. Our predicted magnetic orders and ordering temperatures both at zero and other pressures agree well with experiments including the large increase in the Curie temperature of GdCd under pressure that is shown by our own experimental measurements. From our results it emerges that the Ruderman-Kittel-Kasuya-Yosida interaction on its own can not explain the observed behaviour under pressure, and that the magnetic ordering mechanism is strongly influenced by ...


A Safety And Emissions Analysis Of Continuous Flow Intersections, Joshua Wolfgram 2018 University of Massachusetts Amherst

A Safety And Emissions Analysis Of Continuous Flow Intersections, Joshua Wolfgram

Environmental & Water Resources Engineering Masters Projects

Increasing travel demand, and challenges associated with high percentages of leftturning vehicles, have encouraged the introduction of significant infrastructure advancements. Certain alternative intersection designs, such as continuous flow intersections, median U-turns, and jughandles, eliminate the traditional protected lefterations of these intersection types have been studied to varying degrees, their safety and emissions-related impacts are not well-understood. This project develops a series of microsimulation models for two continuous flow intersections (CFI) located in Missouri and Colorado, and uses the Surrogate Safety Assessment Model (SSAM) to determine the impact of those designs on the location and type of conflicts compared to conventional ...


Improving And Predicting The Effectiveness Of Dispersed, Multi-Disciplinary Design Teams, Matthew Oliver Wald 2018 Brigham Young University

Improving And Predicting The Effectiveness Of Dispersed, Multi-Disciplinary Design Teams, Matthew Oliver Wald

All Theses and Dissertations

The use of dispersed (virtual) teams is growing rapidly in the engineering profession. To help prepare students for work in this type of industry, university engineering courses are requiring students to work in teams. Industry leaders and university faculty are interested in improving and measuring the performance of these distributed teams. Surveys, interviews, and observations from the AerosPACE Partners for the Advancement of Collaborative Engineering (AerosPACE) capstone design course are examined to demonstrate how different collaboration tools can be used to best enhance a distributed design team's effectiveness. Collaboration tools to which distributed design teams should give extra consideration ...


Analyses Of Crowd-Sourced Sound Levels Of Restaurants And Bars In New York City, Gregory S. Farber, Lily M. Wang 2018 SoundPrint

Analyses Of Crowd-Sourced Sound Levels Of Restaurants And Bars In New York City, Gregory S. Farber, Lily M. Wang

Architectural Engineering -- Faculty Publications

For several decades, there has been a significant need to better educate the public about noise pollution. A small number of small-scale studies have focused on the sound levels of restaurants and their impact on health and hearing. There have also been an increasing number of media articles stating that eating and drinking venues are getting increasingly loud making it more difficult for people to connect with others in conversation. This study reports on an exploratory large-scale noise survey of sound levels of 2,376 restaurants and bars in New York City using a novel smart-phone application and categorized them ...


Subjectivity In Failure Mode Effects Analysis (Fmea) Severity Classification Within A Reliability Centered Maintenance (Rcm) Context, Marc Banghart, Kari Babski-Reeves, Linkan Bian, Lesley Strawderman 2018 ERAU

Subjectivity In Failure Mode Effects Analysis (Fmea) Severity Classification Within A Reliability Centered Maintenance (Rcm) Context, Marc Banghart, Kari Babski-Reeves, Linkan Bian, Lesley Strawderman

International Journal of Aviation, Aeronautics, and Aerospace

This research paper investigated subjectivity in the severity rating of failure modes within a risk analysis process. Although several risk analysis processes can be utilized, the study considered the application of Failure Modes Effects Analysis (FMEA) or Failure Modes Effects and Criticality Analysis (FMECA) due to its common use within the Aerospace Industry. The study investigated both differences in severity selection given varying amounts of experience as well as any association between severity selection and the provided input information. The main goal of the research was to investigate the impact of data quality on severity selection and to identify factors ...


Internet Of Underground Things: Sensing And Communications On The Field For Precision Agriculture, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak 2018 University of Nebraska-Lincoln

Internet Of Underground Things: Sensing And Communications On The Field For Precision Agriculture, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak

CSE Conference and Workshop Papers

The projected increases in World population and need for food have recently motivated adoption of information technology solutions in crop fields within precision agriculture approaches. Internet of underground things (IOUT), which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring, emerge from this need. This new paradigm facilitates seamless integration of underground sensors, machinery, and irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. In this paper, state-of-the-art communication architectures are reviewed, and underlying sensing technology and communication mechanisms for IOUT are presented. Recent advances in the ...


Influence Of Classical Anisotropy Fields On The Properties Of Heisenberg Antiferromagnets Within Unified Molecular Field Theory, Tey Lamichhane, Valentin Taufour, Andriy Palasyuk, Qisheng Lin, Sergey Bud’ko, Paul C. Canfield 2018 Iowa State University and Ames Laboratory

Influence Of Classical Anisotropy Fields On The Properties Of Heisenberg Antiferromagnets Within Unified Molecular Field Theory, Tey Lamichhane, Valentin Taufour, Andriy Palasyuk, Qisheng Lin, Sergey Bud’Ko, Paul C. Canfield

Ames Laboratory Accepted Manuscripts

We report on the synthesis of single-crystal and polycrystalline samples of Ce 3 − x Mg x Co 9 solid solution ( 0 ≤ x ≲ 1.4 ) and characterization of their structural and magnetic properties. The crystal structure remains rhombohedral in the whole composition range and Mg partially replaces Ce in the 6 c site of the CeCo 3 structure. Ferromagnetism is induced by Mg substitutions starting as low as x = 0.18 and reaching a Curie temperature as high as 450 K for x = 1.35 . Measurements on single crystals with x = 1.34 and T C = 440     K indicate an axial ...


Doping Evolution Of The Second Magnetization Peak And Magnetic Relaxation In (Ba1−Xkx)Fe2as2 Single Crystals, Yong Liu, Lin Zhou, Kewei Sun, Warren E. Straszheim, Makariy A. Tanatar, Ruslan Prozorov, Thomas A. Lograsso 2018 Ames Laboratory

Doping Evolution Of The Second Magnetization Peak And Magnetic Relaxation In (Ba1−Xkx)Fe2as2 Single Crystals, Yong Liu, Lin Zhou, Kewei Sun, Warren E. Straszheim, Makariy A. Tanatar, Ruslan Prozorov, Thomas A. Lograsso

Ames Laboratory Accepted Manuscripts

We present a thorough study of doping dependent magnetic hysteresis and relaxation characteristics in single crystals of ( B a 1 − x K x ) F e 2 A s 2 ( 0.18 ≤ x ≤ 1 ). The critical current density J c reaches maximum in the underdoped sample x = 0.26 and then decreases in the optimally doped and overdoped samples. Meanwhile, the magnetic relaxation rate S rapidly increases and the flux creep activation barrier U 0 sharply decreases in the overdoped sample x = 0.70 . These results suggest that vortex pinning is very strong in the underdoped regime, but it is greatly ...


Collaborative Appearance-Based Place Recognition And Improving Place Recognition Using Detection Of Dynamic Objects, Juan Pablo Munoz 2018 The Graduate Center, City University of New York

Collaborative Appearance-Based Place Recognition And Improving Place Recognition Using Detection Of Dynamic Objects, Juan Pablo Munoz

All Dissertations, Theses, and Capstone Projects

This dissertation makes contributions to the problem of Long-Term Appearance-Based Place Recognition. We present a framework for place recognition in a collaborative scheme and a method to reduce the impact of dynamic objects on place representations. We demonstrate our findings using a state-of-the-art place recognition approach.

We begin in Part I by describing the general problem of place recognition and its importance in applications where accurate localization is crucial. We discuss feature detection and description and also explain the functioning of several place recognition frameworks.

In Part II, we present a novel framework for collaboration between agents from a pure ...


Climate-Driven Crop Yield And Yield Variability And Climate Change Impacts On The U.S. Great Plains Agricultural Production, Meetpal Singh Kukal, Suat Irmak 2018 University of Nebraska-Lincoln

Climate-Driven Crop Yield And Yield Variability And Climate Change Impacts On The U.S. Great Plains Agricultural Production, Meetpal Singh Kukal, Suat Irmak

Biological Systems Engineering: Papers and Publications

Climate variability and trends affect global crop yields and are characterized as highly dependent on location, crop type, and irrigation. U.S. Great Plains, due to its significance in national food production, evident climate variability, and extensive irrigation is an ideal region of investigation for climate impacts on food production. This paper evaluates climate impacts on maize, sorghum, and soybean yields and effect of irrigation for individual counties in this region by employing extensive crop yield and climate datasets from 1968–2013. Variability in crop yields was a quarter of the regional average yields, with a quarter of this variability ...


Vision-Based Assistive Indoor Localization, Feng Hu 2018 The Graduate Center, City University of New York

Vision-Based Assistive Indoor Localization, Feng Hu

All Dissertations, Theses, and Capstone Projects

An indoor localization system is of significant importance to the visually impaired in their daily lives by helping them localize themselves and further navigate an indoor environment. In this thesis, a vision-based indoor localization solution is proposed and studied with algorithms and their implementations by maximizing the usage of the visual information surrounding the users for an optimal localization from multiple stages. The contributions of the work include the following: (1) Novel combinations of a daily-used smart phone with a low-cost lens (GoPano) are used to provide an economic, portable, and robust indoor localization service for visually impaired people. (2 ...


Real-Time Variable Multidelay Controller For Multihazard Mitigation, Liang Cao, Simon Laflamme 2018 Iowa State University

Real-Time Variable Multidelay Controller For Multihazard Mitigation, Liang Cao, Simon Laflamme

Civil, Construction and Environmental Engineering Publications

High performance control systems (HPCS), including semiactive, active, and hybrid damping systems, are effective solutions to increase structural performance versus multihazard excitations. However, the implementation of HPCS within structural systems is still in its infancy, because of the complexity in designing a robust closed-loop control system that can ensure reliable and high mitigation performance. To overcome this challenge, a new type of controller with high adaptive capabilities is proposed. The control algorithm is based on real-time embedding of measurements to minimally represent the essential dynamics of the controlled system, therefore providing adaptive input space capabilities. This type of controller is ...


Propeller Design Requirements For Quadcopters Utilizing Variable Pitch Propellers, Ian R. McAndrew, Elena Navarro, Ken Witcher 2018 Embry-Riddle Aeronautical University

Propeller Design Requirements For Quadcopters Utilizing Variable Pitch Propellers, Ian R. Mcandrew, Elena Navarro, Ken Witcher

Publications

Unmanned aerial vehicles, UAV, has increases in the drastically in these past several years since their costs reduced. This research is based and built upon previous research presented in a conference. With the advent of commercial Quadcopters, four propeller systems, are used, being designed and used to operate the advantages of both flight and hovering. The basic design of their propeller blades has not evolved from the early days of manned flight when wooden fixed blades were used. In this paper that expands upon previous findings and discussions it explores the historical developments. Furthermore, how the expansion and reduction in ...


Salmonella And Fecal Indicator Bacteria Survival In Soils Amended With Poultry Manure, Claire E. Hruby, Michelle L. Soupir, Thomas B. Moorman, Carl H. Pederson, Rameshwar S. Kanwar 2018 Iowa State University

Salmonella And Fecal Indicator Bacteria Survival In Soils Amended With Poultry Manure, Claire E. Hruby, Michelle L. Soupir, Thomas B. Moorman, Carl H. Pederson, Rameshwar S. Kanwar

Agricultural and Biosystems Engineering Publications

Minimizing the risks associated with manure-borne pathogenic microorganisms requires an understanding of microbial survival under realistic field conditions. The objective of this 3-year study was to assess the fate of Salmonella (SALM) and fecal indicator bacteria (FIB), E. coli (EC) and enterococci (ENT), in glacial till-derived soils, after application of poultry manure (PM) to cornfields under chisel-plowed (CP) or no-till (NT) management. From 2010 to 2012, soil samples were obtained each spring at 0–15- and 15–30-cm depths, to determine whether over-wintering of target bacteria had occurred. Sampling was followed by application of PM at low (PM1) and high ...


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