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Jual Obat Aborsi Manado 081249176664 Obat Aborsi Cytotec & Gastrul Manado, Obat Aborsi Sulawesi 2019 University of South Carolina - Beaufort

Jual Obat Aborsi Manado 081249176664 Obat Aborsi Cytotec & Gastrul Manado, Obat Aborsi Sulawesi

Obat Aborsi Sulawesi

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Battery-Free Wireless Strain Measurement Using An Antenna Sensor, Yang Wang 2019 Georgia Institute of Technology

Battery-Free Wireless Strain Measurement Using An Antenna Sensor, Yang Wang

Archived Webinars

A battery-free antenna sensor can wirelessly measure strain on a structure. Bonded to the surface of a base structure, the antenna sensor deforms when the structure is under strain, causing the antenna’s electromagnetic resonance frequency to change. This resonance frequency change can be wirelessly interrogated and recorded by a reader through electromagnetic backscattering. A radio frequency identification (RFID) chip on the sensor harnesses a small amount of energy from the interrogation signal and responds to the reader. The resonance frequency change identified by the reader is then used to determine the strain applied on the structure. The latest antenna ...


Incidence Of An Astronaut Not Sealing The Pressure Garment Visor On Reentry, Cameron M. Smith, Trent Tresch 2019 Portland State University

Incidence Of An Astronaut Not Sealing The Pressure Garment Visor On Reentry, Cameron M. Smith, Trent Tresch

Journal of Human Performance in Extreme Environments

Audiovisual records of a Project Mercury pilot’s activities during an orbital flight indicate that his visor was left open during reentry and descent to the sea surface, phases of flight during which cabin pressure loss was to be mitigated by suit pressurization; however, the suit could not have been pressurized with the visor open. Thus, for a presently unknown reason, a critical safety step—sealing the visor and making a pressure suit integrity test before reentry—was overlooked in this flight. Later, Space Shuttle flights were carried out with visors unsealed for much of the launch and landing phases ...


Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew McKenna, David Woodward 2019 Technological University Dublin

Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew Mckenna, David Woodward

Articles

A problem increasingly faced by airport authorities is the maintenance of runways. Due to their large aircraft loadings associated with take-off and landing operations, runways experience surface deterioration. Poor quality runway surfaces cannot be tolerated in such an environment. Maintenance issues must be carried out to maximise safety and minimise the risk of aircraft damage. A recent development has been the introduction of self-healing technologies such as rejuvenator encapsulation, induction and microwave heating to address these issues. This paper summarises a laboratory investigation to determine the effectiveness of microwave self-healing for crack repair of Porous Friction Course (PFC) used for ...


Concrete Grinding Residue: Its Effect On Roadside Vegetation And Soil Properties, Halil Ceylan, Yang Zhang, Bora Cetin, Sunghwan Kim, Bo Yang, Chenyi Luo, Robert Horton, Kasthurirangan Gopalakrishnan 2019 Iowa State University

Concrete Grinding Residue: Its Effect On Roadside Vegetation And Soil Properties, Halil Ceylan, Yang Zhang, Bora Cetin, Sunghwan Kim, Bo Yang, Chenyi Luo, Robert Horton, Kasthurirangan Gopalakrishnan

Halil Ceylan

Concrete grinding residue (CGR) is a slurry waste consisting of water and concrete fines generated from diamond grinding operations that is used to smooth a concrete pavement surface. During this process, CGRs are mostly disposed along the roadside, which can influence soils and plant communities along the roadways. To understand the effects of CGR on soil physical and chemical properties and plant growth, a controlled field site at the Kelly Farm in Iowa was used with CGR application rates of 0, 10, 20, and 40 dry ton/acre to test properties of soils and plants before the application and one ...


Large-Scale Performance Testing Of Temporary Sediment Basin Treatments And High-Rate Lamella Settlers, Michael A. Perez, Wesley C. Zech, Jose C. Vasconcelos, Xing Fang 2019 Iowa State University

Large-Scale Performance Testing Of Temporary Sediment Basin Treatments And High-Rate Lamella Settlers, Michael A. Perez, Wesley C. Zech, Jose C. Vasconcelos, Xing Fang

Michael Perez

Sediment basins are temporary practices commonly used to detain stormwater runoff and capture suspended sediment on construction sites. A 79.0 m3 (2790 ft3) sediment basin testing apparatus at the Auburn University—Erosion and Sediment Control Testing Facility was used to provide a series of controlled and repeatable, large-scale tests to understand the performance of sediment basins and provide improvements. This research evaluated five sediment basin configurations over the course of 27 individual tests, including: (1) a standard configuration, (2) the addition of an excavated sump upstream of a ditch check, (3) the modification of the first baffle, (4) a ...


Performance Evaluations Of Three Silt Fence Practices Using A Full-Scale Testing Apparatus, R. Alan Bugg, Wesley Donald, Wesley Zech, Michael A. Perez 2019 Auburn University

Performance Evaluations Of Three Silt Fence Practices Using A Full-Scale Testing Apparatus, R. Alan Bugg, Wesley Donald, Wesley Zech, Michael A. Perez

Michael Perez

Erosion and sediment controls on construction sites minimize environmental impacts from sediment-laden stormwater runoff. Silt fence, a widely specified perimeter control practice on construction projects used to retain sediment on-site, has limited performance-based testing data. Silt fence failures and resultant sediment losses are often the result of structural failure. To better understand silt fence performance, researchers at the Auburn University-Erosion and Sediment Control Testing Facility (AU-ESCTF) have evaluated three silt fence options to determine possible shortcomings using standardized full-scale testing methods. These methods subject silt fence practices to simulated, in-field conditions typically experienced on-site without the variability of field testing ...


Investigation Of Friction Mechanisms In Finger Pad Sliding Against Surfaces Of Varying Roughness, Geetha Chimata, Christian J. Schwartz 2019 Iowa State University

Investigation Of Friction Mechanisms In Finger Pad Sliding Against Surfaces Of Varying Roughness, Geetha Chimata, Christian J. Schwartz

Christian Schwartz

Human finger pad friction and the effects of surface features on the fingerprint ridges, shape of the finger and the material properties of the finger were investigated. The friction coefficients for three fine-grit abrasive papers were measured to assess these effects. Four probing surfaces were used: human index finger pad, silicone replicas of the finger with and without fingerprints, and a smooth silicone sphere. Friction tests were performed at a constant normal load of 0.5 N in two probe orientations: normal and perpendicular to the orientation of the fingerprint ridges. Scanning electron microscopy of the abrasive papers was performed ...


Investigation Of The Effect Of The Normal Load On The Incidence Of Friction Blisters In A Skin-Simulant Model, Geetha Chimata, Christian J. Schwartz 2019 Iowa State University

Investigation Of The Effect Of The Normal Load On The Incidence Of Friction Blisters In A Skin-Simulant Model, Geetha Chimata, Christian J. Schwartz

Christian Schwartz

A laminar skin simulant was constructed to study the incidence of friction blisters. The skin simulant consists of a thin polyurethane top layer and textured gum foam rubber bottom layer adhered to an acrylic-backing plate to emulate the layered structure of the human skin. Friction blisters were produced on the skin simulant by using a dual-axis tribometer. The effect of the applied normal load on the number of cycles required to produce a blister was investigated. The skin simulant was also analyzed as an adhesive-bonded laminar composite to determine the relationship between the applied normal load and the number of ...


Swine Finishing Room Air Infiltration: Part 2. Infiltration As Affected By Room Characteristics, Harishchandra T. Jadhav, Steven J. Hoff, Jay D. Harmon, Daniel S. Andersen 2019 Iowa State University

Swine Finishing Room Air Infiltration: Part 2. Infiltration As Affected By Room Characteristics, Harishchandra T. Jadhav, Steven J. Hoff, Jay D. Harmon, Daniel S. Andersen

Steven J. Hoff

Data collected on 17 swine finishing rooms from the Midwest region of the United States was used to study the relationship between infiltration rate and selected room characteristics. Effect of individual room characteristics on room infiltration rate were tested by simple linear regression (SLR) while multiple linear regression (MLR) was used to develop models for improved prediction. SLR results revealed that the total (It) and other (Io; non-curtain/fan locations) swine finishing room infiltration rates were inversely related to room width and directly related to room length and ceiling height. As expected, rooms with higher curtain end pocket overlap, curtain ...


Hvac Techniques For Modern Livestock And Poultry Production Systems, Steven J. Hoff 2019 Iowa State University

Hvac Techniques For Modern Livestock And Poultry Production Systems, Steven J. Hoff

Steven J. Hoff

Thermal modification for housed livestock and poultry production (HLPP) systems has evolved from outside raised or uncontrolled naturally ventilated building systems into sophisticated computer-controlled cloud-analyzed complexes in the quest for producing a safe, reliable, sustainable, and efficient protein supply for our ever-growing population. This chapter discusses a few of the various HLPP systems used in the USA and details the design process in quantifying the needs for our housed livestock and poultry. Specific emphasis is placed on general building characteristics, general ventilation design features, heat stress control, and systems designed to address animal welfare.


Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon 2019 Iowa State University

Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon

Steven J. Hoff

The thermal environment (TE) inside livestock and poultry facilities has a substantial impact on animal growth performance and facility energy usage; therefore, the TE must be quantified correctly to maintain the optimal TE that maximizes feed efficiency and consumes minimal resources. To achieve this goal, a TE sensor array (TESA) and accompanying data acquisition system were previously developed to measure dry-bulb temperature (tdb), black globe temperature, airspeed, and relative humidity (RH). While measurement of each parameter is useful individually, it is more informative when they are combined to estimate and assess the total impact that the TE has on an ...


Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon 2019 Iowa State University

Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon

Jay D. Harmon

The thermal environment (TE) inside livestock and poultry facilities has a substantial impact on animal growth performance and facility energy usage; therefore, the TE must be quantified correctly to maintain the optimal TE that maximizes feed efficiency and consumes minimal resources. To achieve this goal, a TE sensor array (TESA) and accompanying data acquisition system were previously developed to measure dry-bulb temperature (tdb), black globe temperature, airspeed, and relative humidity (RH). While measurement of each parameter is useful individually, it is more informative when they are combined to estimate and assess the total impact that the TE has on an ...


Swine Finishing Room Air Infiltration: Part 2. Infiltration As Affected By Room Characteristics, Harishchandra T. Jadhav, Steven J. Hoff, Jay D. Harmon, Daniel S. Andersen 2019 Iowa State University

Swine Finishing Room Air Infiltration: Part 2. Infiltration As Affected By Room Characteristics, Harishchandra T. Jadhav, Steven J. Hoff, Jay D. Harmon, Daniel S. Andersen

Jay D. Harmon

Data collected on 17 swine finishing rooms from the Midwest region of the United States was used to study the relationship between infiltration rate and selected room characteristics. Effect of individual room characteristics on room infiltration rate were tested by simple linear regression (SLR) while multiple linear regression (MLR) was used to develop models for improved prediction. SLR results revealed that the total (It) and other (Io; non-curtain/fan locations) swine finishing room infiltration rates were inversely related to room width and directly related to room length and ceiling height. As expected, rooms with higher curtain end pocket overlap, curtain ...


Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto 2019 Quattrone Nanofabrication Facility

Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto

Protocols and Reports

This progress report describes fabrication of silicon nitride membranes from Si wafers using cleanroom techniques, and of nanopore preparation via a self-assembled PS-b-PMMA film. A 36.9 nm thick membrane is successfully prepared by KOH wet etching. The membrane is a layered structure of 36.8 µm thick Si and 116 nm thick silicon nitride. It is also exhibited that in the 47 nm thick PS-b-PMMA film, the nanopore structure is observed in the vicinity of a dust particle, but most of the area indicates lamellar domain structure. The thickness of PS-b-PMMA film will ...


Impact Of Hydraulic Residence Time On Nitrate Removal In Pilot-Scale Woodchip Bioreactors, E. A. Martin, Morgan P. Davis, Thomas B. Moorman, Thomas M. Isenhart, Michelle L. Soupir 2019 Iowa State University

Impact Of Hydraulic Residence Time On Nitrate Removal In Pilot-Scale Woodchip Bioreactors, E. A. Martin, Morgan P. Davis, Thomas B. Moorman, Thomas M. Isenhart, Michelle L. Soupir

Michelle L. Soupir

Nitrate (NO3−N) export from row crop agricultural systems with subsurface tile drainage continues to be a major water quality concern. Woodchip bioreactors are an effective edge-of-field practice designed to remove NO3−N from tile drainage. The NO3−N removal rate of woodchip bioreactors can be impacted by several factors, including hydraulic residence time(HRT). This study examined the impact of three HRTs, 2 h, 8 h, and 16 h, on NO3−N removal in a set of nine pilot-scale woodchip bioreactors in Central Iowa. NO3−N concentration reduction from the inlet to the outlet was significantly different for all ...


Refsoil+: A Reference Database For Genes And Traits Of Soil Plasmids, Taylor K. Dunivin, Jinlyung Choi, Adina Howe, Ashley Shade 2019 Michigan State University

Refsoil+: A Reference Database For Genes And Traits Of Soil Plasmids, Taylor K. Dunivin, Jinlyung Choi, Adina Howe, Ashley Shade

Adina Howe

Plasmids harbor transferable genes that contribute to the functional repertoire of microbial communities, yet their contributions to metagenomes are often overlooked. Environmental plasmids have the potential to spread antibiotic resistance to clinical microbial strains. In soils, high microbiome diversity and high variability in plasmid characteristics present a challenge for studying plasmids. To improve the understanding of soil plasmids, we present RefSoil+, a database containing plasmid sequences from 922 soil microorganisms. Soil plasmids were larger than other described plasmids, which is a trait associated with plasmid mobility. There was a weak relationship between chromosome size and plasmid size and no relationship ...


Kinetics, Energetics, And Size Dependence Of The Transformation From Pt To Ordered Ptsn Intermetallic Nanoparticles, Minda Chen, Yong Han, Tian Wei Goh, Rong Sun, Raghu V. Maligal‐Ganesh, Yuchen Pei, Chia‐ Kuang Tsung, James W. Evans, Wenyu Huang 2019 Iowa State University

Kinetics, Energetics, And Size Dependence Of The Transformation From Pt To Ordered Ptsn Intermetallic Nanoparticles, Minda Chen, Yong Han, Tian Wei Goh, Rong Sun, Raghu V. Maligal‐Ganesh, Yuchen Pei, Chia‐ Kuang Tsung, James W. Evans, Wenyu Huang

James W. Evans

The outstanding catalytic activity and chemical selectivity of intermetallic compounds make them excellent candidates for heterogeneous catalysis. However, the kinetics of their formation at the nanoscale is poorly understood or characterized, and precise control of their size, shape as well as composition during synthesis remains challenging. Here, using well-defined Pt nanoparticles (5 nm and 14 nm) encapsulated in mesoporous silica, we study the transformation kinetics from monometallic Pt to intermetallic PtSn at different temperatures by a series of time-evolution X-ray diffraction studies. Observations indicate an initial transformation stage mediated by Pt surface-controlled intermixing kinetics, followed by a second stage with ...


What Contributes To Problem Complexity In Engineering Problem Solving?, John K. Jackman, LeAnn Faidley, Matt Hagge, Gloria K. Starns, Stephen Gilbert 2019 Iowa State University

What Contributes To Problem Complexity In Engineering Problem Solving?, John K. Jackman, Leann Faidley, Matt Hagge, Gloria K. Starns, Stephen Gilbert

Stephen B. Gilbert

The concept of a cognitive zone of proximal development first proposed by Vygotsky suggests that learning occurs when students solve problems that are just outside of their comfort zone (i.e., a problem that they have not seen before). In engineering problem solving this takes the form of matching the appropriate problem complexity with a student’s internal schema in a particular knowledge domain. If we are going to provide effective learning environments for engineering students, two questions need to be addressed, namely, (1) how should we measure problem complexity and (2) how do we assess the current state of ...


Global Air Quality Trekkers: Clean Kitchen Study, Stephanie Schiavo, Samantha Dykhuis, Avalin Senefeld 2019 Purdue University

Global Air Quality Trekkers: Clean Kitchen Study, Stephanie Schiavo, Samantha Dykhuis, Avalin Senefeld

Engagement & Service-Learning Summit: Connecting Through Listening & Scholarship

No abstract provided.


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