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- Kurt A. Rosentrater (7)
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Articles 1 - 30 of 45
Full-Text Articles in Engineering
Dislocation Structures And The Deformation Of Materials, Marisol Koslowski, Richard Alan Lesar, Robb Thomson
Dislocation Structures And The Deformation Of Materials, Marisol Koslowski, Richard Alan Lesar, Robb Thomson
Richard Alan Lesar
We present results from phase-field simulations of a two-dimensional model of dislocation microstructure development under increasing strain that incorporates the effects of the full, three-dimensional, microstructure in an approximate way. Despite its simplicity, the model yields quantitative predictions of both the deformation properties of face-centered cubic metals as well as key descriptors of the evolving microstructure over a wide range of stress and strain. The present results have important implications for how we interpret and describe the deformation properties of fcc materials.
Strain-Induced Disorder And Phase Transformation In Hexagonal Boron Nitride Under Quasi-Homogeneous Pressure: In Situ X-Ray Study In A Rotational Diamond Anvil Cell, Valery I. Levitas, J. Hashemi, Y. Z. Ma
Strain-Induced Disorder And Phase Transformation In Hexagonal Boron Nitride Under Quasi-Homogeneous Pressure: In Situ X-Ray Study In A Rotational Diamond Anvil Cell, Valery I. Levitas, J. Hashemi, Y. Z. Ma
Valery I. Levitas
One of the challenges in characterization of strain-induced transformations is to create uniform pressure. In this letter, conditions for nearly homogeneous pressure distribution are predicted and achieved experimentally. Compared to hydrostatic loading, plastic shear generally reduces the transformation pressure significantly. We observed, however, an unexpected phenomenon: the transformation of hexagonal to superhard wurtzitic BN under pressure and shear initiated at a pressure comparable to that in hydrostatic compression ($\sim 10$ \ensuremath{{\rm ~GPa}}). In situ X-ray diffraction revealed that plastic shear increases the disorder, while hydrostatic compression does not. This increase neutralizes the transition pressure reduction caused by shear. For the …
Trapezoidal Phase-Shifting Method For 3d Shape Measurement, Peisen S. Huang, Song Zhang, Fu-Pen Chiang
Trapezoidal Phase-Shifting Method For 3d Shape Measurement, Peisen S. Huang, Song Zhang, Fu-Pen Chiang
Song Zhang
We propose a novel structured light method, namely trapezoidal phase-shifting method, for 3-D shape measurement. This method uses three patterns coded with phase-shifted, trapezoidal-shaped gray levels. The 3-D information of the object is extracted by direct calculation of an intensity ratio. Theoretical analysis showed that this new method was significantly less sensitive to the defocusing effect of the captured images when compared to the traditional intensity-ratio based methods. This important advantage makes large-depth 3-D shape measurement possible. If compared to the sinusoidal phase-shifting method, the resolution is similar, but the processing speed is at least 4.5 times faster. The feasibility …
Ordered Network Phases In Linear Poly(Isoprene-B-Styrene-B-Ethylene Oxide) Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Travis S. Bailey, Ryan S. Waletzko, Cordell M. Hardy, Frank S. Bates
Ordered Network Phases In Linear Poly(Isoprene-B-Styrene-B-Ethylene Oxide) Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Travis S. Bailey, Ryan S. Waletzko, Cordell M. Hardy, Frank S. Bates
Eric W. Cochran
The equilibrium phase behavior of 43 linear poly(isoprene-b-styrene-b- ethylene oxide) (ISO) triblock copolymer melts, with molecular weights that place these materials near the order-disorder transition, is reported. Ordered phase morphologies were characterized using small-angle X-ray scattering, transmission electron microscopy, dynamic mechanical spectroscopy, and static birefringence measurements. Interpretation of these results was aided by a modeling technique that facilitates resolution of reciprocal and real-space experimental data, leading to definitive three-dimensional morphological structures. Three distinct multiply continuous network morphologies are identified across a range of compositions between 0.1 ≤ f o ≤ 0.3, situated between two-domain and three-domain lamellae, where f o …
On The Equilibrium States Predicted By Second Moment Models In Rotating, Stably Stratified Homogeneous Shear Flow, Minsuk Ji, Paul A. Durbin
On The Equilibrium States Predicted By Second Moment Models In Rotating, Stably Stratified Homogeneous Shear Flow, Minsuk Ji, Paul A. Durbin
Paul A. Durbin
The structural equilibrium behavior of the general linear second-moment closure model in a stably stratified, spanwise rotating homogeneous shear flow is considered with the aid of bifurcation analysis. A closed form equilibrium solution for the anisotropy tensor aij, dispersion tensor Kij, dimensionless scalar variance q2/k (S/Sθ)2, and the ratio of mean to turbulent time scale ε/Sk is found. The variable of particular interest to bifurcation analysis, ε/Sk is shown as a function of the parameters characterizing the body forces: Ω/S (the ratio of the rotation rate to the mean shear rate) for rotation and Rig (the gradient Richardson number) for …
Avalanches And Scaling In Plastic Deformation, Marisol Koslowski, Richard Alan Lesar, Robb Thomson
Avalanches And Scaling In Plastic Deformation, Marisol Koslowski, Richard Alan Lesar, Robb Thomson
Richard Alan Lesar
Plastic deformation of crystalline materials is a complex nonhomogeneous process characterized by avalanches in the motion of dislocations. We study the evolution of dislocation loops using an analytically solvable phase-field model of dislocations for ductile single crystals during monotonic loading. The distribution of dislocation loop sizes is given by P(A)∼A−σ, with σ=1.8±0.1. The exponent is in agreement with those found in acoustic emission experiments. This model also predicts a range of macroscopic behaviors in agreement with observation, including hardening with monotonic loading, and a maximum in the acoustic emission signal at the onset of yielding.
Microscale Simulation Of Martensitic Microstructure Evolution, Valery I. Levitas, Alexander V. Idesman, Dean L. Preston
Microscale Simulation Of Martensitic Microstructure Evolution, Valery I. Levitas, Alexander V. Idesman, Dean L. Preston
Valery I. Levitas
A new model for the evolution of multivariant martensitic microstructure in single crystals and polycrystals is developed. In contrast with Landau-Ginzburg models, which are limited in practice to nanoscale specimens, this new scale-free model is valid for length scales greater than 100 nm and without an upper bound. It is based on a thermodynamic potential in the volume fractions of the martensitic variants that exhibits an instability resulting in microstructure formation. Simulated microstructures in elastic single crystals and polycrystals under uniaxial loading are in qualitative agreement with those observed experimentally.
Biomolecule-Directed Assembly Of Nanoscale Building Blocks Studied Via Lattice Monte Carlo Simulation, Ting Chen, Monica H. Lamm, Sharon C. Glotzer
Biomolecule-Directed Assembly Of Nanoscale Building Blocks Studied Via Lattice Monte Carlo Simulation, Ting Chen, Monica H. Lamm, Sharon C. Glotzer
Monica H. Lamm
The self-assembly of functionalized inorganic nanoscale building blocks (NBB) was investigated using recognitive biomolecule linkers. The NBBs and linkers were studied using bond fluctuation model and algorithm on a simple cubic lattices. The loops contained in the soluble material to avoid double counting when calculating the fraction of loops. The algorithm was used to calculate additional network properties when volume fractions above the percolation threshold was simulated.
Network Phases In Abc Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Cordell M. Hardy, Travis S. Bailey, Ryan S. Waletzko, Frank S. Bates
Network Phases In Abc Triblock Copolymers, Thomas H. Epps Iii, Eric W. Cochran, Cordell M. Hardy, Travis S. Bailey, Ryan S. Waletzko, Frank S. Bates
Eric W. Cochran
Many naturally occurring and engineered products are influenced by network structures. Collagen networks provide a scaffold for living tissue, while swollen arrays of physically cross-linked polypeptides constitute gelatin, the familiar dessert and electrophoresis medium. Although the associated mesh sizes differ by several orders of magnitude, these examples share a common feature: three-dimensional connectivity that imparts mechanical rigidity. Intercalating additional interconnected components can yield broader functions, e.g., ionic or electrical conductivity, optical band gaps, and tailored heat and mass transfer.
Shear-Induced Network-To-Network Transition In A Block Copolymer Melt, Eric W. Cochran, Frank S. Bates
Shear-Induced Network-To-Network Transition In A Block Copolymer Melt, Eric W. Cochran, Frank S. Bates
Eric W. Cochran
The tricontinuous (10, 3)c shear-induced network-to-network transition in a block copolymer melt was analyzed using small-angle x-ray scattering. Investigations show that field-induced network-to-network phase transition was unprecedented in soft condensed matter. It was found that shear transforms were used for self-assembling the soft material into a single crystal (10, 3)d network. The results show the delicate nature of block copolymers phase behavior, where candidate morphologies were spaced closely together on the free energy surface.
Contribution Of Support Means To Stresses Developed In Sheet Metal Coils, Jonathan A. Wickert, Y.M. Lee
Contribution Of Support Means To Stresses Developed In Sheet Metal Coils, Jonathan A. Wickert, Y.M. Lee
Jonathan A. Wickert
Sheet metal is often stored in large wound coils and processed through such manufacturing stages as cleaning, coating, and slitting in a finishing plant or thickness reduction in a rolling mill. During winding and unwinding operations, as well as during storage and transportation, a coil can be supported in a variety of methods. The coil can be formed on a relatively compliant fiber core, or it can be mounted with the core onto a drive shaft or a pair of core chucks. The stresses within the coil develop in response to the sheet metal's material properties, the process tension, and …
An Undergraduate Engineering Curriculum For Agri-Industrial Facility Designers, David R. Bohnhoff, Sundaram Gunasekaran, Gregory D. Williams, Kurt A. Rosentrater
An Undergraduate Engineering Curriculum For Agri-Industrial Facility Designers, David R. Bohnhoff, Sundaram Gunasekaran, Gregory D. Williams, Kurt A. Rosentrater
Kurt A. Rosentrater
Faculty of the Biological Systems Engineering Department at the University of Wisconsin-Madison are considering modifications to their undergraduate engineering curriculum that will result in graduates who are better prepared for positions as agri-industrial facility designers.
Design Considerations For The Construction And Operation Of Feed Milling Facilities. Part I: Planning, Structural, And Life Safety Considerations, Gregory D. Williams, Kurt A. Rosentrater
Design Considerations For The Construction And Operation Of Feed Milling Facilities. Part I: Planning, Structural, And Life Safety Considerations, Gregory D. Williams, Kurt A. Rosentrater
Kurt A. Rosentrater
Feed mills represent an important segment of our food production system, supplying the nutritional need for animals in our meat supply system. Agri-industrial facilities such as feed mills have a number of unique design requirements that are relatively unknown. The purpose of this paper is to summarize state of the art design procedures for feed milling facilities constructed in North America. To this end, in Part I of this series, planning, life safety, and structural design criteria for these facilities are examined and relevant theory is presented. Additional resources are cited for further study of concepts. This paper should be …
Design Considerations For The Construction And Operation Of Feed Milling Facilities. Part Ii: Process Engineering Considerations, Kurt A. Rosentrater, Gregory D. Williams
Design Considerations For The Construction And Operation Of Feed Milling Facilities. Part Ii: Process Engineering Considerations, Kurt A. Rosentrater, Gregory D. Williams
Kurt A. Rosentrater
Feed milling facilities represent an important segment of our food production system, because they manufacture the majority of products used to meet the nutritional needs of livestock in our meat supply chain. Agri-industrial facilities such as feed mills have a number of unique design requirements. In an effort to summarize state of the art design procedures for feed milling facilities constructed in North America, an overview of these procedures and accepted standards has been assembled. Specifically, this paper focuses on process engineering considerations. Consequently, engineers and designers should become familiar with the distinctive design process for these facilities and develop …
Design Considerations For The Construction And Operation Of Grain Elevator Facilities. Part Ii: Process Engineering Considerations, Kurt A. Rosentrater, Gregory D. Williams
Design Considerations For The Construction And Operation Of Grain Elevator Facilities. Part Ii: Process Engineering Considerations, Kurt A. Rosentrater, Gregory D. Williams
Kurt A. Rosentrater
Grain elevators play a key role in U.S. agriculture, and fulfill three main functions: post-harvest handling and storing of cereal grains and oilseeds, conditioning and preserving of grain, and facilitating the delivery of grain to domestic feeding and processing, as well as overseas, end-use destinations. These facilities have evolved from mere storage sites to large, high-throughput, highly automated, processing plants. This trend has been driven by the consolidation of local country elevators, which has been due, in part, to both local economic conditions as well as changing railroad regulations. Another reason has been an increased demand for grain storage space, …
Design Considerations For The Construction And Operation Of Grain Elevator Facilities. Part I: Planning, Structural, And Life Safety Considerations, Gregory D. Williams, Kurt A. Rosentrater
Design Considerations For The Construction And Operation Of Grain Elevator Facilities. Part I: Planning, Structural, And Life Safety Considerations, Gregory D. Williams, Kurt A. Rosentrater
Kurt A. Rosentrater
Grain elevators represent a major link our food production system. To date, information about the unique design requirements of these facilities has been limited. In an effort to summarize state of the art design procedures for grain elevator facilities constructed in North America, an overview of accepted standards and procedures has been assembled. With this paper engineers should become more familiar with specific design considerations for grain handling facilities and develop appropriate references to expand their knowledge base. Educators may find this paper useful too.
Can-Based Distributed Control For Autonomous Vehicles, Matthew J. Darr, Timothy S. Stombaugh, Scott A. Shearer, John P. Fulton
Can-Based Distributed Control For Autonomous Vehicles, Matthew J. Darr, Timothy S. Stombaugh, Scott A. Shearer, John P. Fulton
Matthew J. Darr
Through the work of researchers and the development of commercially available products, automated guidance has become a viable option for agricultural producers. One limiting factor of many commercially available technologies is that they only automate one function of an agricultural vehicle and that their control systems are proprietary to a single machine model.The objective of this project was to evaluate a controller area network (CAN bus) as the basis of an automated agricultural vehicle. The prototype system utilized several microcontroller-driven nodes to act as control points along a system wide CAN bus. Messages were transferred to the steering, transmission, and …
Application Rate And Timing Effects On Urease Inhibitor Performance For Minimizing Ammonia Emissions From Beef Cattle Feedyards, David B. Parker, Syam Pandrangi, L. Wayne Greene, Lal K. Almas, N. Andy Cole, Marty B. Rhoades, Jacek A. Koziel
Application Rate And Timing Effects On Urease Inhibitor Performance For Minimizing Ammonia Emissions From Beef Cattle Feedyards, David B. Parker, Syam Pandrangi, L. Wayne Greene, Lal K. Almas, N. Andy Cole, Marty B. Rhoades, Jacek A. Koziel
Jacek A. Koziel
A laboratory study was conducted to evaluate how rate and timing of urease inhibitor application affects ammonia emissions from simulated beef cattle feedyard surfaces. The urease inhibitor N-(n-butyl)thiophosphoric triamide (NBPT) was applied at rates of 0, 1 and 2 kg/ha, at 8, 16, and 32 day frequencies, and with or without simulated rainfall. Synthetic urine was added every 2 days to the manure surface. Gaseous NH3 was trapped in a sulfuric acid solution using a vacuum system and analyzed for nitrogen using automated procedures. NBPT applied every 8 days was most effective, with the 1 and 2 kg/ha NBPT treatments …
Multidimensional Gas Chromatography-Olfactometry For Identification And Prioritization Of Malodors From Confined Animal Feeding Operations, Donald W. Wright, David K. Eaton, Lawrence T. Nielsen, Fred W. Kuhrt, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker
Multidimensional Gas Chromatography-Olfactometry For Identification And Prioritization Of Malodors From Confined Animal Feeding Operations, Donald W. Wright, David K. Eaton, Lawrence T. Nielsen, Fred W. Kuhrt, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker
Jacek A. Koziel
Odor profiling efforts were directed at applying to high-density livestock operations, some of the lessons learned in resolving past, highly diverse, odor-focused investigations in the consumer product industry. Multidimensional-GC-Olfactometry was utilized in an attempt to define and prioritize the basic building blocks of odor character associated with representative cattle feedyard and swine feeding operations. Although scores of potential odorant volatiles have been previously identified in high-density livestock operations, the odor profile results developed herein suggest that only a very few of these may constitute the preponderance of the odor complaints associated with these environments. This appeared to be especially true …
Evaluation Of Sample Recovery Of Malodorous Gases From Air Sampling Bags, Spme, And Sampling Canisters, Jacek A. Koziel, Jarett P. Spinhirne, Jenny D. Lloyd, David B. Parker, Donald W. Wright, David K. Eaton, Lawrence T. Nielsen
Evaluation Of Sample Recovery Of Malodorous Gases From Air Sampling Bags, Spme, And Sampling Canisters, Jacek A. Koziel, Jarett P. Spinhirne, Jenny D. Lloyd, David B. Parker, Donald W. Wright, David K. Eaton, Lawrence T. Nielsen
Jacek A. Koziel
Odorous gases associated with livestock operations are complex mixtures of hundreds if not thousands of compounds. Research is needed to know how best to sample and analyze these compounds. The main objective of this research was to compare recoveries of a standard gas mixture of 11 odorous compounds from the Carboxen/PDMS 75 µ m SPME fibers, PVF (Tedlar), FEP (Teflon), foil, and PET (Melinex) air sampling bags, and standard 6 L Stabilizer™ sampling canisters after sample storage at room temperature. A standard mixture consisted of 7 VFAs from acetic to hexanoic, and 4 semi-VOCs including p-cresol, indole, 4-ethylphenol, and 2'-aminoacetopheone …
Release And Transport Of Nutrients From Livestock Manure Applied To Pastureland, Michelle L. Soupir, Saied Mostaghimi, Eugene R. Yagow, David H. Vaughan
Release And Transport Of Nutrients From Livestock Manure Applied To Pastureland, Michelle L. Soupir, Saied Mostaghimi, Eugene R. Yagow, David H. Vaughan
Michelle L. Soupir
Land applications of manure from confined animal systems and direct deposit by grazing animals are both major sources of nutrients in streams. An understanding of the overland transport mechanisms from land applied waste is needed to improve design of best management practices and modeling of NPS pollution. Release and transport plots were established to study in-field nutrient release and transport from pasturelands receiving phosphorus based livestock waste applications. The release plots determined the concentrations available to be transported to the edge of the field in runoff. Four manure treatments (turkey litter, liquid dairy manure, standard cowpies, and none) and three …
Educational Needs For Agri-Industrial Facility Designers And Managers, Gregory D. Williams, Kurt A. Rosentrater, David R. Bohnhoff
Educational Needs For Agri-Industrial Facility Designers And Managers, Gregory D. Williams, Kurt A. Rosentrater, David R. Bohnhoff
Kurt A. Rosentrater
This paper summarizes educational needs for agri-industrial facility designers and mangers. Relevant skills required for the design, planning, and operation of agri-industrial facilities are discussed. Continuing and University educational needs for facility designers and managers are also presented.
Analysis Of Factors Affecting Corn Masa Byproduct Generation, Kurt A. Rosentrater
Analysis Of Factors Affecting Corn Masa Byproduct Generation, Kurt A. Rosentrater
Kurt A. Rosentrater
The production of corn masa-based products in the U.S. has been increasing over the last several years, and consequently, so has the volume of waste materials generated from this processing sector. These byproducts, which consist of corn dry matter losses that occur during the nixtamalization process, are currently underutilized, but have much potential for value-added processing and utilization, and thus hold the simultaneous promises of economic benefit for corn processors as well as decreased potential impact on surrounding ecosystems. Because information concerning masa byproducts, and the rate at which they are generated, is currently very limited and not readily available, …
Comparison Of Vrt Granular Applicators, John P. Fulton, Scott A. Shearer, Steven F. Higgins, Timothy S. Stombaugh, Matthew J. Darr, Dennis W. Hancock, Edward L. Hutchins
Comparison Of Vrt Granular Applicators, John P. Fulton, Scott A. Shearer, Steven F. Higgins, Timothy S. Stombaugh, Matthew J. Darr, Dennis W. Hancock, Edward L. Hutchins
Matthew J. Darr
Granular applicators equipped with variable-rate technology have gained popularity in recent years due to increased interests in variable-rate application. The purpose of this investigation was to characterize distribution patterns at varying rates and quantify rate transitions from various granular applicators. Both uniform- and variable-rate tests were conducted to assess the accuracy of variable-rate application from four granular applicators (2 spinner spreaders and 2 pneumatic applicators). The patterns results indicated a consistent triangular pattern for spinner spreader B and consistent patterns for pneumatic applicators C and D. However, applicator D produced pattern variations at the center and right side. Simulated overlap …
Ambient Ammonia And Hydrogen Sulfide Concentrations At A Beef Cattle Feedlot In Texas, Jacek A. Koziel, Bok-Haeng Baek, Jarett P. Spinhirne, David B. Park
Ambient Ammonia And Hydrogen Sulfide Concentrations At A Beef Cattle Feedlot In Texas, Jacek A. Koziel, Bok-Haeng Baek, Jarett P. Spinhirne, David B. Park
Jacek A. Koziel
Concentrations of ammonia (NH3) and hydrogen sulfide (H2S) in ambient air were semicontinuously measured at a 50,000-head cattle feedyard in Texas panhandle in three seasons: fall 2002 (10 days), winter 2003 (14 days), and spring 2003 (15 days). Sampling was conducted at 1.5 m above the ground at one location each season at the western fence line of cattle pens. Gas concentrations were measured using continuous analyzers housed in an onsite instrument shelter. Measured concentrations were upwind or downwind of the feedyard pens depending on the wind direction. Wind directions, wind velocity, and air temperature were measured to correlate them …
Scatterer Size Estimation In Pulse-Echo Ultrasound Using Focused Sources: Calibration Measurements And Phantom Experiments, Timothy A. Bigelow, William D. O'Brien
Scatterer Size Estimation In Pulse-Echo Ultrasound Using Focused Sources: Calibration Measurements And Phantom Experiments, Timothy A. Bigelow, William D. O'Brien
Timothy A. Bigelow
In a companion paper [T. A. Bigelow and W. D. O'Brien Jr., J. Acoust. Soc. Am. 116, 578 (2004)], theory, supported by simulations, showed that accurate scatterer size estimates could be obtained using highly focused sources provided that the derived generalized attenuation-compensation function was used and the velocity potential field near the focus could be approximated as a three-dimensional Gaussian. Herein, the theory is further evaluated via experimental studies. A calibration technique is developed to find the necessary equivalent Gaussian dimensions for a focused source using reflections obtained from a rigid plane scanned through the focus. Then, the theoretical analysis …
Scatterer Size Estimation In Pulse-Echo Ultrasound Using Focused Sources: Theoretical Approximations And Simulation Analysis, Timothy A. Bigelow, William D. O'Brien
Scatterer Size Estimation In Pulse-Echo Ultrasound Using Focused Sources: Theoretical Approximations And Simulation Analysis, Timothy A. Bigelow, William D. O'Brien
Timothy A. Bigelow
The speckle in ultrasound images has long been thought to contain information related to the tissue microstructure. Many different investigators have analyzed the frequency characteristics of the backscattered signals to estimate the scatterer acoustic concentration and size. Previous work has been mostly restricted to unfocused or weakly focused ultrasound sources, thus limiting its implementation with diagnostically relevant fields. Herein, we derive equations capable of estimating the size of a-scatterer for any reasonably focused source provided that the velocity potential field in the focal region can be approximated as a three-dimensional Gaussian beam, scatterers are a sufficient distance from the source, …
Estrogen Content Of Dairy And Swine Wastes, D. Raj Raman, Elizabeth L. Williams, Alice C. Layton, Robert T. Burns, James P. Easter, Adam S. Daugherty, Michael D. Mullen, Gary S. Sayler
Estrogen Content Of Dairy And Swine Wastes, D. Raj Raman, Elizabeth L. Williams, Alice C. Layton, Robert T. Burns, James P. Easter, Adam S. Daugherty, Michael D. Mullen, Gary S. Sayler
D. Raj Raman
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentra tions in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17β-estradiol (E2), estrone (E1), and 17α-estradiol by gas chromatography−mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to …
Reliable First-Principles Alloy Thermodynamics Via Truncated Cluster Expansions, Nikolai A. Zarkevich, Duane D. Johnson
Reliable First-Principles Alloy Thermodynamics Via Truncated Cluster Expansions, Nikolai A. Zarkevich, Duane D. Johnson
Nikolai A. Zarkevich
In alloys cluster expansions (CE) are increasingly used to combine first-principles electronicstructure calculations and Monte Carlo methods to predict thermodynamic properties. As a basis-set expansion in terms of lattice geometrical clusters and effective cluster interactions, the CE is exact if infinite, but is tractable only if truncated. Yet until now a truncation procedure was not well defined and did not guarantee a reliable truncated CE. We present an optimal truncation procedure for CE basis sets that provides reliable thermodynamics. We then exemplify its importance in Ni3V, where the CE has failed unpredictably, and now show agreement to a range of …
The North Carolina State University Women In Science And Engineering Program: A Community For Living And Learning, Sarah A. Rajala, Laura J. Bottomley, E. A. Parry, J. D. Cohen, Susan C. Grant, C. J. Thomas, T. M. Doxey, G. Perez, R. E. Collins, J. E. Spurlin
The North Carolina State University Women In Science And Engineering Program: A Community For Living And Learning, Sarah A. Rajala, Laura J. Bottomley, E. A. Parry, J. D. Cohen, Susan C. Grant, C. J. Thomas, T. M. Doxey, G. Perez, R. E. Collins, J. E. Spurlin
Sarah A. Rajala
Women are underrepresented in many of the disciplines in engineering, the mathematical sciences, and the physical and natural sciences, both at the undergraduate and the graduate levels. Depending upon the discipline, we lose women at varying points along the way. The pipeline of women interested in studying in engineering disciplines and in physics, for example, narrows considerably at the undergraduate level. In other disciplines such as mathematics, the retention rate for women at major research universities is much lower than at liberal arts institutions and the percentage of women who pursue graduate studies is much lower than that of their …