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Articles 285601 - 285630 of 303843
Full-Text Articles in Physical Sciences and Mathematics
Petrology And Mineralogy Of Tertiary Volcanic Rocks In The Vicinity Of The Rozel Hills And Black Mountain, Box Elder County, Utah, Elizabeth R. Greenman
Petrology And Mineralogy Of Tertiary Volcanic Rocks In The Vicinity Of The Rozel Hills And Black Mountain, Box Elder County, Utah, Elizabeth R. Greenman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Two basalt flows and an andesite fissure eruption occur in the Rozel Hills - Black Mountain area in Box Elder County, Utah. Both basalt flows are aphanitic, and contain olivine, plagioclase, augite, and opaque oxides. They may be distinguished both chemically and on the basis of their textures. Unit 2 basalt is finer grained, and appears to be associated with a fault in the Black Mountain area. Chemically, it is similar to high-iron lavas in the Craters of the Moon, Idaho area. It has higher alkali, total iron, and titanium contents that Unit 1 basalt. Unit 1 basalt is similar …
On The Transport Equations For Anisotropic Plasmas, Abdallah R. Barakat
On The Transport Equations For Anisotropic Plasmas, Abdallah R. Barakat
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
First, I attempt to present a unified approach to the study of transport phenomena in multicoponent anisotropic space plasmas. In the limit of small temperature anisotropies this system of generalized transport equations reduces to Grad's 13-moment system of transport equations. In the collisionless limit, the generalized transport equations account for collisionless heat flow, collisionless viscosity, and large temperature anisotropies. Also, I show that with the appropriate assumptions, the system of generalized transport equations reduces to all of the other major systems of transport equations for anisotropic plasmas that have been derived to date.
Next, for application to aeronomy and space …
Parameter Estimation In Nonstationary M/M/S Queueing Models, Pensri Vajanaphanich
Parameter Estimation In Nonstationary M/M/S Queueing Models, Pensri Vajanaphanich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
If either the arrival rate or the service rate in an M/M/S queue exhibit variability over time, then no steady state solution is available for examining the system behavior. The arrival and service rates can be represented through Fourier series approximations. This permits numerical approximation of the system characteristics over time.
An example of an M/M/S representation of the operations of emergency treatment at Logan Regional hospital is presented. It requires numerical integration of the differential equation for L(t), the expected number of customers in the system at time t.
The Use Of Contingency Table Analysis As A Robust Technique For Analysis Of Variance, Mei-Eing Chiu
The Use Of Contingency Table Analysis As A Robust Technique For Analysis Of Variance, Mei-Eing Chiu
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper is to compare Analysis of Variance with Contingency Table Analysis when the data being analyzed do not satisfy Analysis of Variance assumptions. The criteria for comparison are the powers of the Standard variance-ratio and the Chi-square test.
The test statistic and powers were obtained by Monte Carlo.
1. Calculate test statistic for each of 100 trials, this process was repeated 12 times. Each time different combination of means and variances were used.
2. Powers were obtained for each of 12 combinations of means and variances.
Whether Analysis of Variance or Contingency Table Analysis is a …
Numerical Methods (Finite Element) For Time-Dependent Partial Differential Equations, Masaji Watanabe
Numerical Methods (Finite Element) For Time-Dependent Partial Differential Equations, Masaji Watanabe
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This paper surveys reasons why the Ritz method and the Galerkin method are not efficient and why these methods can not be applied directly, for time dependent problems. It also introduces methods that are used for those problems. For a linear boundary value problem defined by a positive definite symmetric (self-adjoint) operator, the existence and the convergence of the Ritz approximation are guaranteed. In non-symmetric case, Lax-Milgram lemma assures the existence and the convergence of the Galerkin approximation for H1/2(Ω)-elliptic operator. Since time-dependent problems are hyperbolic or parabolic, the existence and the convergence of approximations by those methods are not …
Linear Regression Of The Poisson Mean, Duane Steven Brown
Linear Regression Of The Poisson Mean, Duane Steven Brown
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this thesis was to compare two estimation procedures, the method of least squares and the method of maximum likelihood, on sample data obtained from a Poisson distribution. Point estimates of the slope and intercept of the regression line and point estimates of the mean squared error for both the slope and intercept were obtained. It is shown that least squares, the preferred method due to its simplicity, does yield results as good as maximum likelihood.
Also, confidence intervals were computed by Monte Carlo techniques and then were tested for accuracy. For the method of least squares, confidence …
Petrology Of The Middle Cambrian Blacksmith Formation, North-Central Utah, Howard William Hay Jr.
Petrology Of The Middle Cambrian Blacksmith Formation, North-Central Utah, Howard William Hay Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The dolostones and dolomitic limestones of the Middle Cambrian Blacksmith Formation were studied in the Bear River and Malad Ranges and the Wellsville Mountains of north-central Utah. The depositional textures and sedimentary structures retained within the rocks form the basis of subdivisions of measured sections, interpretation of depositional paleogeography, and reconstruction of environments.
Other studies of modern carbonate environments and their ancient analogues provided the basis for interpretation of the depositional textures found within the rocks of the Blacksmith Formation. Four identifiable lithofacies were recognized within the study area. These facies include: (1) oolite shoal; (2) restricted lagoon; (3) low- …
Discrete Modeling Of Minimal Surfaces, C. Coppin, Donald Greenspan
Discrete Modeling Of Minimal Surfaces, C. Coppin, Donald Greenspan
Mathematics Technical Papers
A new computer approach to the modeling of minimal surfaces is described and implemented. Quasi-molecular particles and forces are used to simulate actual molecular structure and forces. Detailed formulas and computer techniques are given. As an example, the approximation of the unique minimal surface through a skew quadrilateral is constructed and displayed.
Remarks On First And Second Order Periodic Boundary Value Problems, V. Lakshmikantham
Remarks On First And Second Order Periodic Boundary Value Problems, V. Lakshmikantham
Mathematics Technical Papers
We consider the first and second order periodic boundary value problems (PBVP for brevity)[see pdf for notation] and [see pdf for notation]and obtain the existence of extremal solutions as limits of monotone iterates. In [2] and [3], the monotone method was employed for the problems (1.1) and (1.2) when the corresponding lower and upper solutions a(t),B(t) satisfy [see pdf for notation] in addition to other conditions. Furthermore, when f is increasing, it is shown [2,3] that the conditions (1.3) and (1.4) are tantamount to assuming the existence of a periodic solution. Accordingly, the problem of proving the existence of periodic …
Structural Identification Of Large Systems By Reduction To Subsystems: Vldl Triglycerides, S. M. Grundy, Jerome Eisenfeld
Structural Identification Of Large Systems By Reduction To Subsystems: Vldl Triglycerides, S. M. Grundy, Jerome Eisenfeld
Mathematics Technical Papers
Experiments are performed for identification purposes, i.e. to identify the values of unknown paprameters from data. In the event that one or more parameters can not be identified, the cause could be the result of a variety of problems: insuffcient or infrequent sampling, random or nonrandom disturbances, numerical ill-conditioning and etc. The input-output configuration may also be the cause of non-identifiability. In other words, evenif the sampling and numerical procedure could be carried out under the most ideal conditions, certain parameters may not be identifiable because these parameters are not uniquely contained in the transfer function, in which case these …
Electro-Optics Applications For Alleviating Emi/Emc/Emp Problems, George H. Baker, Walter H. Hardwick
Electro-Optics Applications For Alleviating Emi/Emc/Emp Problems, George H. Baker, Walter H. Hardwick
George H Baker
No abstract provided.
Trace Analysis Of Uranium By Laser Induced Fluorescence Excitation ( Life ), R. Kenneth Marcus
Trace Analysis Of Uranium By Laser Induced Fluorescence Excitation ( Life ), R. Kenneth Marcus
Theses & Honors Papers
No abstract provided.
The Impact Of Solid State Science In Our Society, Juana Acrivos
The Impact Of Solid State Science In Our Society, Juana Acrivos
Faculty Publications, Chemistry
No abstract provided.
Comparison Of Fishery Policies And Management Techniques Of The United States And Iceland, Ted I. Lillestolen
Comparison Of Fishery Policies And Management Techniques Of The United States And Iceland, Ted I. Lillestolen
Marine Affairs Theses and Major Papers
In 1976, the United States enacted the Fishery Conservation and Management Act (FCMA), presently referred to as the Magnuson Fishery conservation and Management Act (MFCMA). The legislation is a complex and detailed document establishing for the first time a national fishery policy. The Act also created an organizational structure designed to implement this new policy. Since the Act's implementation, there has been a great deal of controversy, especially generated by the commercial fishermen. This paper focuses on Iceland, primarily because of its great economic dependency on its fisheries resources, unlike the United States.
Geometries And General Features Of Some Cenozoic Valleys And Valley Fills, Western Nebraska, Robert F. Diffendal Jr.
Geometries And General Features Of Some Cenozoic Valleys And Valley Fills, Western Nebraska, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
Portions of Tertiary and Quaternary valleys and valley fills have been exhumed by recent stream erosion at many sites in western Nebraska. Paleovalleys vary from narrow, steep-sided, high gradient tributary gullies less than 0.1 km wide to broad, flat-floored valleys produced by lateral erosion. Segments of valley floors may be nearly smooth in the case of a Quaternary example, or may be very irregular with potholes and other deep scour features. Paleovalley sides, when exposed, are often steeply sloping, and approaching or possibly going beyond the vertical where the valleys have been eroded into the Brule Formation. Paleovalleys range in …
Abstracts Of Contributed Papers, 94th Session, Iowa Academy Of Science, April 16-17, 1982, Iowa Academy Of Science
Abstracts Of Contributed Papers, 94th Session, Iowa Academy Of Science, April 16-17, 1982, Iowa Academy Of Science
Iowa Academy of Science Documents
Presentation abstracts from the annual meeting of the Iowa Academy of Science
The Annual Meeting Of The Iowa Academy Of Science April 16-17, 1982 [Program, 94th Meeting], Iowa Academy Of Science
The Annual Meeting Of The Iowa Academy Of Science April 16-17, 1982 [Program, 94th Meeting], Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
Test 1432: Ford 7610 And 7710 (16x4) Diesel 8 And 16-Speed, Nebraska Tractor Test Lab
Test 1432: Ford 7610 And 7710 (16x4) Diesel 8 And 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …
Test 1431: Ford 6610 And 6710 (16x8) Diesel 8 And 16-Speed, Nebraska Tractor Test Lab
Test 1431: Ford 6610 And 6710 (16x8) Diesel 8 And 16-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …
Reaction ⁶Li(P, Δ⁺⁺)⁶He At 1.04 Gev And The Δ−N Interaction, T. Hennino, D. Bachelier, Oleksa-Myron Bilaniuk, J. L. Boyard, J. C. Jourdain, M. Roy-Stephen, P. Radvanyi, M. Bedjidian, E. Descroix, P. Foessel, S. Gardien, J. Y. Grossiord, A. Guichard, M. Gusakow, R. Haroutunian, M. Jacquin, J. R. Pizzi, A. Garin
Reaction ⁶Li(P, Δ⁺⁺)⁶He At 1.04 Gev And The Δ−N Interaction, T. Hennino, D. Bachelier, Oleksa-Myron Bilaniuk, J. L. Boyard, J. C. Jourdain, M. Roy-Stephen, P. Radvanyi, M. Bedjidian, E. Descroix, P. Foessel, S. Gardien, J. Y. Grossiord, A. Guichard, M. Gusakow, R. Haroutunian, M. Jacquin, J. R. Pizzi, A. Garin
Physics & Astronomy Faculty Works
The reaction ⁶Li(p, Δ⁺⁺)⁶He has been studied at 1.04 GeV for transferred momenta ranging from 0.11 to 0.35 (GeV/c)2. An exponential decrease of the cross section is observed. A Glauber-type calculation is presented. The possibility of extracting information on σ(ΔN) and α(ΔN) is discussed.
Book Review: The Theory Of Atomic Structure And Spectra By Robert D. Cowan, Anthony F. Starace
Book Review: The Theory Of Atomic Structure And Spectra By Robert D. Cowan, Anthony F. Starace
Anthony F. Starace Publications
The field of atomic spectroscopy is currently experiencing a resurgence of interest owing on the one hand to its applications in astrophysics, plasma physics, and other fields and on the other hand to the development of new experimental tools to probe atomic structures. One example of the latter is the use of tunable lasers to study highly excited atoms in the presence of strong external electric and magnetic fields. Another is the use of synchrotron radiation to probe with increasing detail the inner shell structure of rare earth, actinide, and other heavy atoms.
Photoelectron Angular Distributions: Energy Dependence For S Subshells, Steven T. Manson, Anthony F. Starace
Photoelectron Angular Distributions: Energy Dependence For S Subshells, Steven T. Manson, Anthony F. Starace
Anthony F. Starace Publications
An overview of the theory of photoelectron angular distributions for atoms is presented. Its features, which are embodied in a single asymmetry parameter β in the electric dipole approximation, are examined within the framework of the angular momentum transfer formulation. The β parameter is in principle always energy dependent. Within the LS coupling approximation, however, there are instances, each representing a multitude of particular photoionization processes, in which β is an analytically determined constant. The energy dependence of the β parameters in such instances is due entirely to spin-orbit and other relativistic interactions. The study of the energy dependence of …
You Can Make Money Producing And Marketing Alfalfa In The 80'S, David C. Petritz
You Can Make Money Producing And Marketing Alfalfa In The 80'S, David C. Petritz
Kentucky Alfalfa and Stored Forage Conference
We are today, as we were during most of the 70's, concerned with the future of the forage enterprise and the livestock species that depend on it. Will they survive an environment in which the emphasis is on grain exports? Will they survive in an environment in which consumers are not able (but hopefully willing) to pay prices for red meats which are profitable for all segments of the livestock industry? Will they survive in the 80's when real interest rates will be relatively high?
Marketing Alternatives For Kentucky Alfalfa: Needs, Challenges And Opportunities, J. Kenneth Evans
Marketing Alternatives For Kentucky Alfalfa: Needs, Challenges And Opportunities, J. Kenneth Evans
Kentucky Alfalfa and Stored Forage Conference
There are unquestionable needs for more high quality alfalfa in the Southeastern U.S. From these needs arise the challenge and opportunities for those who are researching, informing, teaching, and even promoting alfalfa. Likewise, there are income opportunities for those who own resources which could be used in producing and marketing alfalfa. This paper will discuss some of the factors which should be considered in hay marketing, i.e., (1) a dependable supply of hay; (2) producing high quality hay; and (3) planning to supply the highest quality hay to the highest priced market.
Hay - The National And International Traveler, Harry D. Gates Jr.
Hay - The National And International Traveler, Harry D. Gates Jr.
Kentucky Alfalfa and Stored Forage Conference
Prior to 1883, packing, shipping and hauling hay was an irregular business. There was no established custom to govern, and every transaction was typical of the parties engaged in it.
The hay crop had become the leading agricultural product in value, and its importance commercially was appreciated. The amount of hay leaving the farm had steadily increased, but trade environment did not offer much encouragement for businessmen of regular methods, or the capitalist to embark in the business, and it was apparent to every thinking person that for the proper development of so important an industry it was necessary in …
Development Of Local Hay Association, Roger Sparrow, Eric Hinton, J. H. Ragland
Development Of Local Hay Association, Roger Sparrow, Eric Hinton, J. H. Ragland
Kentucky Alfalfa and Stored Forage Conference
The need for a Hay marketing "system" had been obvious to hay sellers and agricultural leaders in Larue County for some time. Five or six hay producers had been selling mainly alfalfa hay to truckers, who would transport the hay to a buyer and reap the profit. Hay was mostly sold by the bale and at a low price. Because of the land and soil type, Larue County had a good potential to produce alfalfa as a cash crop. The development of this potential was being limited by an unreliable and unprofitable market. Given these conditions, the development of a …
Alfalfa From The Consumer Standpoint, John Williams
Alfalfa From The Consumer Standpoint, John Williams
Kentucky Alfalfa and Stored Forage Conference
Traditionally, horsemen in this part of the United States have fed grass hay mixed with good red clover hay to their horses in training as well as their horses on the farm. Knowing that legume hay is high in protein, horsemen found this is a good source of the needed protein for their animals no matter what activity they were engaged in. A few problems were found with clover hay. First of all, it was usually dusty and, if not made under ideal circumstances, the hay was dark and in some cases moldy. The hay could never be purchased in …
Innovations In Hay Harvesting And Storing, V. L. Lectenberg, D. A. Holt
Innovations In Hay Harvesting And Storing, V. L. Lectenberg, D. A. Holt
Kentucky Alfalfa and Stored Forage Conference
Haymaking in the humid parts of the U.S. is the most risky operation that farmers engage in. Standing hay is extremely high in moisture and must be dried to at least 25% moisture less before it can be stored without spoilage. Most farmers rely on natural field drying processes to cure their hay. Natural drying is often slowed by high relative humidity. Rainfall frequently occurs before the hay has dried which further slows the drying process and can result in serious nutrient and yield losses. Haymaking is also a labor-intensive farming operation and, until recently, involved a large amount of …
Breaking The Alfalfa Yield Barrier, J. Paul Mueller
Breaking The Alfalfa Yield Barrier, J. Paul Mueller
Kentucky Alfalfa and Stored Forage Conference
During the past one-hundred or so years, alfalfa production has spread and flourished in the United States. It has contributed to progress in many phases of the livestock industry.
No-Till Establishement Of Alfalfa, Harlan E. White, Dale D. Wolf
No-Till Establishement Of Alfalfa, Harlan E. White, Dale D. Wolf
Kentucky Alfalfa and Stored Forage Conference
The no-till concept has been widely accepted in Virginia for corn and soybean production. However, alfalfa is still commonly established by plowing and tilling the soil into a fine seedbed. Each year many tons of productive topsoil is eroded by rainfall on those prepared seedbeds. The resulting gullies remain in the hayfield for the life of the stand to damage equipment and "rattle the teeth" of the operator.