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Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand 2010 Université de Bordeaux

Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand

Civil and Environmental Engineering Faculty Research and Publications

Microcantilevers used as (bio)chemical sensors are usually coated with a chemically sensitive layer. The coated devices operate either in a static bending regime or in a dynamic flexural mode. While the coated devices operate generally well in both the static and dynamic mode, they do suffer from certain shortcomings depending on the medium of operation and the application, including lack of selectivity and of reversibility of the sensitive coating and a reduced quality factor due to the surrounding medium. In particular, the performance of microcantilevers excited in their standard out-of-plane dynamic mode drastically decreases in viscous liquid media. Moreover ...


Climate Change Impacts On Water Demand And Salinity In California's Irrigated Agriculture, Gerrit Schoups, Edwin P. Maurer, Jan Hopmans 2010 Santa Clara University

Climate Change Impacts On Water Demand And Salinity In California's Irrigated Agriculture, Gerrit Schoups, Edwin P. Maurer, Jan Hopmans

Civil, Environmental and Sustainable Engineering

This paper examines potential regional-scale impacts of climate change on sustainability of irrigated agriculture, focusing on the western San Joaquin Valley in California. We consider potential changes in irrigation water demand and supply, and quantify impacts on the hydrologic system, soil and groundwater salinity with associated crop yield reductions. Our analysis is based on archived output from General Circulation Model (GCM) climate projections through 2100, which were downscaled to the 1,400 km2 study area. We account for uncertainty in GCM climate projections by considering two different GCM's, each using three greenhouse gas emission scenarios. Significant uncertainty in projected ...


Sediment-Size Analysis, Nitrate Monitoring, Bathymetric Mapping And Construction Of A Two-Dimensional Hydrodynamic Model Of A Backwater Region Of The Upper Mississippi River System 2008-2009, Nathan Anderson Quarderer 2010 University of Iowa

Sediment-Size Analysis, Nitrate Monitoring, Bathymetric Mapping And Construction Of A Two-Dimensional Hydrodynamic Model Of A Backwater Region Of The Upper Mississippi River System 2008-2009, Nathan Anderson Quarderer

Theses and Dissertations

In April 2008, the non-profit organization Living Lands & Waters (LL&W) approached IIHR-Hydroscience and Engineering to assist with the preliminary scoping and assessment for the proposed dredging and restoration of the backwater region located near the confluence of the Iowa and Mississippi Rivers, commonly referred to as Boston Bay. IIHR was responsible for the measurement and analysis of relevant physical and chemical parameters including particle-size analysis of sediment cores; real-time monitoring of nitrate-nitrogen concentration of agricultural runoff entering Boston Bay; bathymetric surveying; as well as the development of a two-dimensional hydrodynamic capable of simulating the proposed dredging activity.

Particle-size analysis was achieved using the hydrometer method of sedimentation to determine the distribution of fine particles (silt and clay) while traditional sieving techniques were employed to establish the proportions of sand-sized particles. Results indicate that the sediment contained in Boston Bay consists primarily of particles with diameters in the range of 2-50 µm, what the USDA considers silt, and clay.

A real-time ...


Effects Of The Antimicrobial Tylosin On The Microbial Community Structure Of An Anaerobic Sequencing Batch Reactor, Toshio Shimada, Xu Li, Julie L. Zilles, Eberhard Morgenroth, Lutgarde Raskin 2010 University of Illinois at Urbana-Champaign

Effects Of The Antimicrobial Tylosin On The Microbial Community Structure Of An Anaerobic Sequencing Batch Reactor, Toshio Shimada, Xu Li, Julie L. Zilles, Eberhard Morgenroth, Lutgarde Raskin

Civil Engineering Faculty Publications

The effects of the antimicrobial tylosin on a methanogenic microbial community were studied in a glucosefed laboratory-scale anaerobic sequencing batch reactor (ASBR) exposed to stepwise increases of tylosin (0, 1.67, and 167 mg/L). The microbial community structure was determined using quantitative fluorescence in situ hybridization (FISH) and phylogenetic analyses of bacterial 16S ribosomal RNA (rRNA) gene clone libraries of biomass samples. During the periods without tylosin addition and with an influent tylosin concentration of 1.67 mg/L, 16S rRNA gene sequences related to Syntrophobacter were detected and the relative abundance of Methanosaeta species was high. During the ...


On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa 2010 University of Nebraska-Lincoln

On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa

Biological Systems Engineering: Papers and Publications

The 1‐D and single layer combination‐based energy balance Penman‐Monteith (PM) model has limitations in practical application due to the lack of canopy resistance (rc) data for different vegetation surfaces. rc could be estimated by inversion of the PM model if the actual evapotranspiration (ETa) rate is known, but this approach has its own set of issues. Instead, an empirical method of estimating rc is suggested in this study. We investigated the relationships between primary micrometeorological parameters and rc and developed seven models to estimate rc for a nonstressed maize canopy on an ...


Closed Course Testing Of Portable Rumble Strips To Improve Truck Safety At Work Zones, Steven D. Schrock, Yong Bai 2010 University of Kansas

Closed Course Testing Of Portable Rumble Strips To Improve Truck Safety At Work Zones, Steven D. Schrock, Yong Bai

Final Reports & Technical Briefs from Mid-America Transportation Center

The purpose of this research was to compare the attention-getting characteristics, movements and vertical displacements of several portable, reusable rumble strips. The attention-getting characteristics and displacement were measured after passes of a fully loaded heavy truck and a passenger vehicle. Sound and vibration tests revealed that the portable plastic rumble strips were more effective on cars than trucks for generating in-vehicle vibration and increasing in-vehicle sound levels. Further, they were generally better able to match the characteristics of the tested permanent rumble strip compared to the adhesive rumble strips, and that this was also true for the configurations that contained ...


Safety Investigation And Guidance For Work-Zone Devices In Freight Transportation Systems Subjected To Passenger Car And Truck Impacts With New Crash Standards, Ronald K. Faller Ph.D., P.E., Dean L. Sicking Ph.D., P.E., Karla A. Lechtenberg M.S.C.E., E.I.T., James C. Holloway M.S.C.E., E.I.T., Jennifer D. Schmidt 2010 University of Nebraska - Lincoln

Safety Investigation And Guidance For Work-Zone Devices In Freight Transportation Systems Subjected To Passenger Car And Truck Impacts With New Crash Standards, Ronald K. Faller Ph.D., P.E., Dean L. Sicking Ph.D., P.E., Karla A. Lechtenberg M.S.C.E., E.I.T., James C. Holloway M.S.C.E., E.I.T., Jennifer D. Schmidt

Final Reports & Technical Briefs from Mid-America Transportation Center

Crashworthy, work-zone, portable sign support systems accepted under NCHRP Report No. 350 were analyzed to predict their safety peformance according to the TL-3 MASH evaluation criteria. An analysis was conducted to determine which hardware parameters of sign support systems would likely contribute to the safety performance with MASH. The acuracy of the method was evaluated through full-scale crash testing. Four full-scale crash tests were conducted with a pickup truck. Two tall-mounted, sign support systems with aluminum sign panels failed the MASH criteria due to windshield penetration. One low-mounted system with a vinyl, roll-up sign panel failed the MASH criteria due ...


161. The Potential Role Of Extensor Muscle Fatigue In The Onset Of Intervertebral Disc Degeneration: A Novel In Vivo Model, Mary Beth M. Grabowsky, Nicholas A. Pallota, Matthew W. Connelly, Brett Van Etten, Rebecca A. Wachs, Max Alley, Joseph C. Glennon, Andrew H. Dubin, John W. German, Richard L. Uhl, Eric H. Ledet 2010 Rensselaer Polytechnic Institute

161. The Potential Role Of Extensor Muscle Fatigue In The Onset Of Intervertebral Disc Degeneration: A Novel In Vivo Model, Mary Beth M. Grabowsky, Nicholas A. Pallota, Matthew W. Connelly, Brett Van Etten, Rebecca A. Wachs, Max Alley, Joseph C. Glennon, Andrew H. Dubin, John W. German, Richard L. Uhl, Eric H. Ledet

Biological Systems Engineering: Papers and Publications

BACKGROUND CONTEXT: Occupation is strongly correlated to low back pain (LBP). Specific occupational activities associated with low back pain include poor posture, whole body vibration, and repetitive lifting. These activities have a common link: they result in fatigue of the primary spinal extensor musculature. This fatigue may lead to increased intervertebral loading - a stimulus for disc degeneration. If true, this association could provide a vital connection between detrimental physical activities and LBP. However, the link between muscle fatigue and increased load across the disc space has never been quantified in vivo.

PURPOSE: The purpose of this study was to develop ...


Route Change Decision Making By Hurricane Evacuees Facing Congestion, R. Michael Robinson, Asad Khattak 2010 Old Dominion University

Route Change Decision Making By Hurricane Evacuees Facing Congestion, R. Michael Robinson, Asad Khattak

VMASC Publications

Successful evacuations of metropolitan areas require overcoming unexpected congestion that reduces traffic flows. Congestion may result from accidents, incidents, or other events that reduce road capacity. Traffic professionals and emergency managers may promote deviations from planned routes to bypass an area of congestion and speed mass exit. However, some route changes may actually reduce traffic flow rates, and in these cases decision makers may want to discourage use of alternate routes. By using results of a behavioral survey of potential hurricane evacuees, this study identifies variables associated with the decision to alter routes and also identifies frequently used information sources ...


Developing A Sustainable Freight Transportation Framework With The Consideration Of Improving Safety And Minimizing Carbon Emissions, Margaret Rita Neff, Yong Bai, Steven Schrock, Thomas E. Mulinazzi 2010 University of Kansas

Developing A Sustainable Freight Transportation Framework With The Consideration Of Improving Safety And Minimizing Carbon Emissions, Margaret Rita Neff, Yong Bai, Steven Schrock, Thomas E. Mulinazzi

Final Reports & Technical Briefs from Mid-America Transportation Center

Despite the difficulties of the American economy in recent years the transportation sector continues to expand. Freight transportation alone has been projected to increase enormously even if the economy as a whole only manages a very moderate growth. Not only does freight transportation use a large percentage of resources but it contributes significantly to America’s share of carbon emissions and affects the safety of the transportation system and all its users. These problems are only expected to increase as the volume of freight transportation is already reaching the limit of the American transportation infrastructure’s capacity and demand continues ...


Improving Freight Fire Safety: Analysis And Testing Of Real Engine Conditions To Progress Development Of Mist-Controlling Additives For Fire Mitigation, Albert Rathner Ph.D. 2010 University of Iowa

Improving Freight Fire Safety: Analysis And Testing Of Real Engine Conditions To Progress Development Of Mist-Controlling Additives For Fire Mitigation, Albert Rathner Ph.D.

Final Reports & Technical Briefs from Mid-America Transportation Center

The formation of a fuel mist resulting from high shear stresses acting on the fuel during violent sloshing and tank rupture under the energy of a crash severely increases the occurrence and intensity of fires in transportation related accidents. In order to minimize such crash-induced fires, adding long chained polymers to diesel fuel was proposed to arrest the break-up of diesel into a fine mist. Such polymers with specifically engineered properties are intended to impart non-Newtonian characteristics to diesel, which would then alter its flow behavior under the applied shear stresses. As a first step in this direction, calculations are ...


Improving Freight Fire Safety: Assessment Of The Effectiveness Of Mist-Controlling Additives In Mitigating Crash-Induced Diesel Fires, Albert Ratner Ph.D. 2010 University of Iowa

Improving Freight Fire Safety: Assessment Of The Effectiveness Of Mist-Controlling Additives In Mitigating Crash-Induced Diesel Fires, Albert Ratner Ph.D.

Final Reports & Technical Briefs from Mid-America Transportation Center

Adding long chained polymers to diesel has been proposed as a method to prevent crash fires by arresting the break-up of diesel fuel into a fine mist in transportation related accidents. The effect of such additives on the flow properties of diesel was investigated by studying the impact of poly-butadiene and diesel blend drops on a solid surface using high speed imaging. The addition of the polymer imparted shear-thinning behavior to diesel, and the base viscosities increased rapidly with polymer concentration. Four concentrations of the polymer were tested at three different impact speeds under atmospheric pressure. Maximum spread factors and ...


Mitigating Wind Induced Truck Crashes, Thomas E. Mulinazzi, Steven Schrock Ph.D., P.E. 2010 University of Kansas

Mitigating Wind Induced Truck Crashes, Thomas E. Mulinazzi, Steven Schrock Ph.D., P.E.

Final Reports & Technical Briefs from Mid-America Transportation Center

Dangerous weather and high wind in particular, is a common contributing factor in truck crashes. High wind speeds have been documented as a perennial cause of truck crashes in Kansas and other Great Plains states. The possibility of reducing such crashes, combined with the installation of dynamic message signs along Interstate 70, created an opportunity for further research. To this end, crash data were obtained from the Kansas Department of Transportation’s Accident Records System for all heavy vehicle crashes on I-70 that involved strong winds. The data were analyzed to determine the correlations between the vehicle and freight characteristics ...


Bottom Flange Reinforcement In Nu I-Girders, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E. 2010 University of Nebraska-Lincoln

Bottom Flange Reinforcement In Nu I-Girders, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E.

Final Reports & Technical Briefs from Mid-America Transportation Center

The 1996 edition of AASHTO Standard Specifications for Highway Bridges stated that nominal confinement reinforcement be placed to enclose prestressing steel in the bottom flange of bridge girders from girder ends to at least a distance equal to the girder’s height. The 2004 edition of AASHTO LRFD Bridge Design Specifications changed the distance over which the confinement reinforcement was to be distributed from 1.0h to 1.5h, and gave minimum requirements for the amount of steel to be used, No.3 bars, and their maximum spacing, not to exceed 6.” Research was undertaken to study what impact, if ...


Development Of Advanced Finite Element Material Models For Cable Barrier Wire Rope, John D. Reid, Karla A. Lechtenberg, Cody S. Stolle 2010 University of Nebraska-Lincoln

Development Of Advanced Finite Element Material Models For Cable Barrier Wire Rope, John D. Reid, Karla A. Lechtenberg, Cody S. Stolle

Final Reports & Technical Briefs from Mid-America Transportation Center

An improved LS-DYNA model of ¾-in. (19-mm) diameter 3x7 wire rope commonly used in roadside cable guardrail installations has been developed. A Belytschko-Schwer beam element was selected along with material *MAT_166. Numerical noise was reduced using part stiffness damping with a coefficient of 2%, and frequency range damping with a coefficient of 12%. The optimum element length based on timestep, accuracy, and computational cost was determined to be between 0.4 and 0.8 in. (10-20 mm). Dynamic component tests were conducted on wire rope to determine material properties. These tests were simulated and the results compared to the physical ...


Foundation Design For High Tension Cable Guardrails, John R. Rohde Ph.D., P.E., Ling Zhu Ph.D., Ryan J. Terpsma B.S.M.E 2010 University of Nebraska - Lincoln

Foundation Design For High Tension Cable Guardrails, John R. Rohde Ph.D., P.E., Ling Zhu Ph.D., Ryan J. Terpsma B.S.M.E

Final Reports & Technical Briefs from Mid-America Transportation Center

High tension cable guardrail is becoming increasing popular in median and roadside applications due to the promise of reduced deflections upon impact and reduced maintenance. As the performance of these systems is observed in service, there is a growing concern over the end anchorage foundation performance of current systems. Foundations for high tension systems must not only be capable of restraining the impact load of a vehicle but must also restrain the initial pretension on the cable system as well as temperature induced loads. While it may be acceptable for many roadside safety devices to require foundation repair after impact ...


Estimating Highway Pavement Damage Costs Attributed To Truck Traffic, Yong Bai, Steven D. Schrock, Thomas E. Mulinazzi, Wenhua Hou, Chunxiao Liu, Umar Firman 2010 University of Kansas

Estimating Highway Pavement Damage Costs Attributed To Truck Traffic, Yong Bai, Steven D. Schrock, Thomas E. Mulinazzi, Wenhua Hou, Chunxiao Liu, Umar Firman

Final Reports & Technical Briefs from Mid-America Transportation Center

Kansas is one of the leaders in meat production in the United States. In the southwest Kansas region, there are more than three hundred feed yards and several of the biggest meat processing plants in the nation. Heavy trucks (e.g., tractor-trailers) have been used primarily for transporting processed meat, meat byproducts, grain, and other related products. With the continuous growth of these industries, there will be more trucks on highways transporting meat and meat-related products in southwest Kansas. These trucks cause noteworthy damage to Kansas highway pavements, which in turn leads to more frequent maintenance actions and ultimately more ...


Safety Climate Of Commercial Vehicle Operation, Linda Ng Boyle Ph.D., Jeffrey Short 2010 University of Washington

Safety Climate Of Commercial Vehicle Operation, Linda Ng Boyle Ph.D., Jeffrey Short

Final Reports & Technical Briefs from Mid-America Transportation Center

Enhancing the safety culture within trucking and motor coach industries has become a key area of concern given the potential impact it has on crashes and overall safety. Many organizations recognize that safety is compromised if the culture within their organization does not promote safety. Unfortunately, the specifics of a good safety culture and the methods by which safety culture is fostered are relatively ambiguous. A key reason for this is the general lack of standardization of the highly qualitative term ―safety climate‖ within the trucking and motor coach industries. A survey was completed by 31 organizations within these industries ...


Extending Asphalt Pavement Life Using Thin Whitetopping, Mustaque Hossain, Sharmin Sultana 2010 Kansas State University

Extending Asphalt Pavement Life Using Thin Whitetopping, Mustaque Hossain, Sharmin Sultana

Final Reports & Technical Briefs from Mid-America Transportation Center

Due to budget constraints, many highway agencies are becoming interested in pavement preservation or rehabilitation rather than reconstruction to ensure pavement is in serviceable condition. Thin whitetopping (TWT) is the process of rehabilitating distressed asphalt concrete (AC) pavements by using a concrete overlay. This study was done to develop a design catalog for existing AC pavements to be overlaid with TWT. The finite element (FE) analysis was performed with SolidWorks, which is the 3-D FE software program used to develop this design catalog. The design considered different TWT thicknesses, existing AC layer thickness and modulus, the bonding condition between TWT ...


An Operational Policy For A Single Vendor Multi Buyer Integrated Inventory Supply Chain System Considering Shipping Time, Chiranjit Saha 2010 Louisiana State University and Agricultural and Mechanical College

An Operational Policy For A Single Vendor Multi Buyer Integrated Inventory Supply Chain System Considering Shipping Time, Chiranjit Saha

LSU Master's Theses

Since its introduction, the concept of integrated inventory supply chain has received a considerable amount of attention. The majority of studies in the last three decades revealed an increase in holding cost as product moves further down the chain or up the chain. A recent study Hoque (2008) considered vendor’s setup cost and inventory holding cost. Some research also considered fixed transportation cost, which is unrealistic. This study focuses on a single-vendor, multi-buyer scenario and presents three models. First, two models illustrate the transferring of equally-sized batches. Then, a third model considers the transferring of unequally-sized batches in a ...


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