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Full-Text Articles in Engineering

Test 1652: Case International 9260 Diesel And Steiger 9260 Diesel 12-Speeds, Nebraska Tractor Test Lab Jan 1991

Test 1652: Case International 9260 Diesel And Steiger 9260 Diesel 12-Speeds, 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 1654: Caterpiller Challenger 75 And 75c Diesel 10-Speed, Nebraska Tractor Test Lab Jan 1991

Test 1654: Caterpiller Challenger 75 And 75c Diesel 10-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 1644: Ford 3930 (8x2) Diesel 8-Speed, Nebraska Tractor Test Lab Jan 1991

Test 1644: Ford 3930 (8x2) Diesel 8-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 1645: Ford 4630 (8x2) Diesel 8-Speed, Nebraska Tractor Test Lab Jan 1991

Test 1645: Ford 4630 (8x2) Diesel 8-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 1647: Ford 8730 Powershift Diesel 18-Speed, Nebraska Tractor Test Lab Jan 1991

Test 1647: Ford 8730 Powershift Diesel 18-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 1649: Case International 9230 And Steiger 9230 (12-Speeds) Diesels, Nebraska Tractor Test Lab Jan 1991

Test 1649: Case International 9230 And Steiger 9230 (12-Speeds) Diesels, 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 1646: Ford 8630 Powershift Diesel 18-Speed, Nebraska Tractor Test Lab Jan 1991

Test 1646: Ford 8630 Powershift Diesel 18-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 …


Nebraska Summary: S103 Ford 3930 8x8, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S103 Ford 3930 8x8, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Bioconcentrations Of Heavy Metals Copper, Chromium (Tot), Lead, Zinc, Nickel And Mercury In The Missouri River 1991 Jan 1991

Bioconcentrations Of Heavy Metals Copper, Chromium (Tot), Lead, Zinc, Nickel And Mercury In The Missouri River 1991

United States Army Corps of Engineers, Omaha District

The presence of heavy metals within aquatic environments can be attributed to sources such as industry, municipal discharges, agriculture and natural processes which release various amounts into natural systems. Metals such as copper, zinc and chromium are listed as essential micronutrients for many plant and animal species. Of potential concern, however, is the tendency of heavy metals to accumulate within the food webs of ecosystems. Classified as biologically hard to degrade, heavy metals may concentrate to significant amounts within the trophic levels of a particular ecosystem. At these increased concentrations many of these heavy metals become toxic to living organisms. …


Performance Of Seedigated And Conventionally Planted Crops, W. S. Leander Jr., Derrel L. Martin, James R. Gilley Jan 1991

Performance Of Seedigated And Conventionally Planted Crops, W. S. Leander Jr., Derrel L. Martin, James R. Gilley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Seedigation is the use of a moving sprinkler irrigation system to broadcast seeds on the soil surface. Seed germination, plant characteristics and yield for grain sorghum, winter wheat and soybeans that were seedigated and conventionally planted are compared. When the seeding rates for seedigation were increased above that for conventional planting, and adequate moisture was available for germination, grain sorghum and wheat seedigated on tilled surfaces produced yields similar to conventionally planted crops. Seedigation of soybeans into fallow conditions, or when used as a relay crop, was unsuccessful. Shallow disking following seedigation did not improve germination or yield of grain …


Mechanical And Barrier Properties Of Edible Corn And Wheat Protein Films, T. P. Aydt, Curtis Weller, R. F. Testin Jan 1991

Mechanical And Barrier Properties Of Edible Corn And Wheat Protein Films, T. P. Aydt, Curtis Weller, R. F. Testin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Published methods for production of homogeneous edible films from com and wheat proteins were adapted. Barrier and mechanical properties of the edible films were evaluated with procedures commonly used on polymeric films. Mechanical property data included thickness, elongation, tensile strength, tear strength, and burst strength measurements. Barrier property data included water vapor, oxygen, and carbon dioxide gas transmission rate measurements. Homogeneous com and wheat protein films were found to have low tensile strengths, far less than cellophane. Com films were brittle while wheat films were elastic in comparison to cellophane. All three types of film had low permeabilities for dry …


A Cooperative Educational Program To Reduce Soil Erosion, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, David A. Biere, Susan Smydra Krotz Jan 1991

A Cooperative Educational Program To Reduce Soil Erosion, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, David A. Biere, Susan Smydra Krotz

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Eastern Nebraska, especially the northeastern portion, has a history of severe soil erosion, due in part to a predominance of steep slopes and highly erodible soils (12). While the average annual allowable soil loss ("T" value) for most of these soils is five tons per acre, some fields have annual soil erosion rates that exceed 100 tons per acre. The loss of topsoil is critical, of course, but erosion from cropland also results in the removal of fertilizers and pesticides, which degrades water quality.

Even though farmers are generally aware that soil erosion is a national problem, many …


Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Elbert C. Dickey, Roger Kanable, Stewart W. Melvin, Charles A. Burr Jan 1991

Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Elbert C. Dickey, Roger Kanable, Stewart W. Melvin, Charles A. Burr

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimating Percent Residue Cover Using the Line-Transect Method

The line-transect method is one of the easiest method to use in the field to determine the percent residue cover on the surface. Accurate measurement is necessary to determine if enough cover is present to comply with the conservation plan.

The following is a step-by-step procedure for using the line-transect method to measure the percentage of residue cover.

Step 1

Use a 100-foot or 50-foot measuring tape for measuring residue cover. Other measuring length or even knotted ropes can be used if the appropriate multiplication factor is used to calculate the percentage. …


Residue Management To Control Soil Erosion By Water, Elbert C. Dickey, David P. Shelton, Paul J. Jasa, Michael C. Hirschi Jan 1991

Residue Management To Control Soil Erosion By Water, Elbert C. Dickey, David P. Shelton, Paul J. Jasa, Michael C. Hirschi

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Erosion Process

Erosion of topsoil begins when water detaches individual soil particles from clod and other soil aggregates. A single raindrop may seem insignificant, yet collectively, raindrops strike the ground with surprising force. During an intense storm, rainfall can loosen and detach up to 100 tons of soil per acre and can be especially erosive when residue mulch or vegetation are not present to absorb their impact.

Two problems often occur during rainstorms. The rate of rainfall can exceed the rate at which water can enter the soil and raindrop impact forces can partially seal the soil surface. In …


Study Of Ingaas-Based Modulation Doped Field Effect Transistor Structures Using Variable-Angle Spectroscopic Ellipsometry, S. A. Alterovitz, R. M. Sieg, H. D. Yao, Paul G. Snyder, John A. Woollam, J. Pamulapati, P. K. Bhattacharya, P. A. P. A. Sekula-Moise Jan 1991

Study Of Ingaas-Based Modulation Doped Field Effect Transistor Structures Using Variable-Angle Spectroscopic Ellipsometry, S. A. Alterovitz, R. M. Sieg, H. D. Yao, Paul G. Snyder, John A. Woollam, J. Pamulapati, P. K. Bhattacharya, P. A. P. A. Sekula-Moise

John A. Woollam Publications

Variable-angle spectroscopic ellipsometry was used to estimate the thicknesses of all layers within the optical penetration depth of InCaAs-based modulation doped field effect transistor structures. Strained and unstrained InGaAs channels were made by molecular beam epitaxy (MBE) on InP substrates and by metal-organic chemical vapor deposition on GaAs substrates. In most cases. ellipsometrically determined thicknesses were within 10% of the growth-calibration results. The MBE-made InCaAs strained layers showed large strain effects, indicating a probable shift in the critical points of their dielectric function toward the InP lattice-matched concentration.


Equipment For Ridge Planting, Elbert C. Dickey, Paul J. Jasa Jan 1991

Equipment For Ridge Planting, Elbert C. Dickey, Paul J. Jasa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In ridge plant systems, crops are planted into ridges formed during cultivation of the previous crop.

Row cleaning devices on the planter push weed seed and residue lying on the soil surface from the ridge to the area between the rows, or row middles. The crop seed is planted into the old row in a cleanly tilled strip at a higher elevation than the row middles. A band application of herbicide behind the planter typically is used in the row for weed control. Crop cultivation controls weeds between the row and rebuilds ridges for the following year.

Ridge plant systems …


Surface Flashover Of Silicon, Frank E. Peterkin, Tim Ridolfi, Lonnie L. Buresh, Brian J. Hankla, D. K. Scott, P. F. Williams, William C. Nunnally, B. L. Thomas Dec 1990

Surface Flashover Of Silicon, Frank E. Peterkin, Tim Ridolfi, Lonnie L. Buresh, Brian J. Hankla, D. K. Scott, P. F. Williams, William C. Nunnally, B. L. Thomas

P. F. (Paul Frazer) Williams Publications

The development of high-voltage semiconductor devices has been hampered by the occurrence of flashover at the surface of the semiconductor. The physical mechanisms responsible for this phenomenon are not understood. We present new empirical information which clarifies the processes responsible for surface flashover in a vacuum ambient by showing clearly that in flashover current flows primarily inside the semiconductor surface rather than in the ambient. This observation is in fundamental disagreement with the standard model for vacuum flashover of insulator surfaces.


Modeling AiXGa1-XAs Optical Constants As Functions Of Composition, Paul G. Snyder, John A. Woollam, Samuel A. Alterovitz, Blaine D. Johs Dec 1990

Modeling AiXGa1-XAs Optical Constants As Functions Of Composition, Paul G. Snyder, John A. Woollam, Samuel A. Alterovitz, Blaine D. Johs

Department of Electrical and Computer Engineering: Faculty Publications

Three models for the dielectric function εx (hv) of AgxGa11-xAs are reviewed. All are based on measured optical constants at discrete compositions. The validity of each mode1 near critical pint energies, and otherwise, is evaluated. Only the energy-shift model is appropriate over the entire available spectrum ( 1.5-6.0 eV), including the band-gap (E0) region.


Acuta Enews November 1990, Vol. 19, No. 11 Nov 1990

Acuta Enews November 1990, Vol. 19, No. 11

ACUTA Newsletters

In This Issue

Election of Directors

ICA backs universities

Vendor Liaison

An end to phone tag

Party Line

Hawaii air fares locked in


Hydraulic Characteristics Of Rills, John E. Gilley, E. R. Kottwitz, J. R. Simanton Nov 1990

Hydraulic Characteristics Of Rills, John E. Gilley, E. R. Kottwitz, J. R. Simanton

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Rill density and rill flow rates were determined during rainfall simulation tests conducted at 11 sites located throughout the eastern United States. A mean rill density of 1.0 rills/m was found for the study locations. From measurements of the relative distribution of flow rates, a procedure is identified for partitioning flow between individual rills.

Regression equations were developed for relating rill width and hydraulic roughness coefficients to flow rate. Equations were also derived for predicting mean flow velocity from visually determined measurements of advance velocity. Information reported in this study can be used to estimate hydraulic characteristics of rills.


Ridge Plant Systems: Fertility, Richard B. Ferguson, Charles A. Shapiro, Elbert C. Dickey, Gary W. Hergert Nov 1990

Ridge Plant Systems: Fertility, Richard B. Ferguson, Charles A. Shapiro, Elbert C. Dickey, Gary W. Hergert

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Soil Sample

The starting point for any fertilizer program, regardless of the tillage system, is obtaining a representative soil sample. Without knowing which nutrients are needed, the questions of what fertilizer and how much to apply become irrelevant. Two types of soil samples should be obtained: the traditional, zero to 8-inch sample for general fertility (pH, phosphorus, potassium, organic matter, etc.) and deep, subsoil samples for nitrate. Subsoil samples for nitrate should be taken to a depth of at least 3 feet.

The problem of how to obtain a representative soil sample is particularly relevant in ridge-tilled fields. On …


Acuta Enews October 1990, Vol. 19, No. 10 Oct 1990

Acuta Enews October 1990, Vol. 19, No. 10

ACUTA Newsletters

In This Issue

Early warning of PVC fires

President's column

Attendant quiets complaints

Party Line

ISDN personalized

What do you charge?


Acuta Enews September 1990, Vol. 19, No. 9 Sep 1990

Acuta Enews September 1990, Vol. 19, No. 9

ACUTA Newsletters

In This Issue

Are colleges aggregators?

President's column

Four workshops scheduled

Revising the directory

A six-node network

Update on Portland


Nondestructive Detection Of An Undeserable Metallic Phase, T1, During Processing Of Alumnum-L Thumalloys, Otto Buck, David J. Bracci, David C. Jiles, Lisa J.H. Brasche, Jeffrey E. Shield, Leonard S. Chumbley Aug 1990

Nondestructive Detection Of An Undeserable Metallic Phase, T1, During Processing Of Alumnum-L Thumalloys, Otto Buck, David J. Bracci, David C. Jiles, Lisa J.H. Brasche, Jeffrey E. Shield, Leonard S. Chumbley

Department of Mechanical and Materials Engineering: Faculty Publications

A method is disclosed for detecting the T1 phase in aluminum-lithium alloys through simultaneous measurement of conductivity and hardness. In employing eddy current to measure conductivity, when the eddy current decreases with aging of the alloy, while the hardness of the material continues to increase, the presence of the T1 phase may be detected.


Acuta Enews August 1990, Vol. 19, No. 8 Aug 1990

Acuta Enews August 1990, Vol. 19, No. 8

ACUTA Newsletters

In This Issue

New President's column

Conference gets high marks

Regions consolidated

Birds of a Feather

Party Line

Summer-time Blues


Acuta Enews July 1990, Vol. 19, No. 5 Jul 1990

Acuta Enews July 1990, Vol. 19, No. 5

ACUTA Newsletters

In This Issue

Long distance aggregators: A new wrinkle

Telecommunications: one of 'hottest' careers

Message From President

Portland Seminar to give full story on TMS

Do thorough check before joining aggregator

Portland Seminar to give full story on TMIS

Party Line

Touch screens may replace Touch Tone

Workstations pay for themselves in 9 months

Univ. of Chicago fits old halls with new wires

Funding sought for high speed 'data highway'


Lpsolver: A Linear Program Solving Package For Educational And Instructional Modeling Applications, Paul Savory, Jeffrey Arthur Jul 1990

Lpsolver: A Linear Program Solving Package For Educational And Instructional Modeling Applications, Paul Savory, Jeffrey Arthur

Department of Industrial and Management Systems Engineering: Faculty Publications

LPSOLVER is a computer program developed to be a learning tool for students studying linear programming. This technical paper contains and overview of what LPSOLVER is and how to use it. The program allows one to enter linear programs in three different formats which are discussed in Section IV. Described in Section VI are the two methods available for solving linear programs. Other features of LPSOLVER are discussed in Section VII. Appendix A describes all the various files that LPSOLVER uses/creates. A listing of error messages is given in Appendix B. Information about how the program was implement is contained …


Acuta Enews June 1990, Vol. 19, No. 6 Jun 1990

Acuta Enews June 1990, Vol. 19, No. 6

ACUTA Newsletters

In This Issue

WMU gets 'complete' cable

President's message

Profiles of new staff members

Orlando update

Election preview

Bulletin Board


Using The Line-Transect Method To Estimate Percent Residue Cover, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, Roger Kanable, Susan Smydra Krotz Jun 1990

Using The Line-Transect Method To Estimate Percent Residue Cover, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, Roger Kanable, Susan Smydra Krotz

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Crop residue left on the soil surface is one of the easiest and most cost-effective methods of reducing soil erosion. ~ Research in Nebraska and other Midwestern states shows ' that leaving as little as 20 percent of the soil surface covered with crop residue can reduce soil erosion by as much as one half of what it would be from residue-free conditions. Greater amounts of residue cover further limit soil erosion, Figure 1.

Residue reduces erosion in two ways. First, the residue dissipates raindrop impact energy, reducing the amount of soil that is detached. Residue also forms a …


Acuta Enews May 1990, Vol. 19, No. 5 May 1990

Acuta Enews May 1990, Vol. 19, No. 5

ACUTA Newsletters

In This Issue

IU installs first cohesive telecom network

Fun for the whole family in Orlando

Message From the President

Membership to elect VP, Secretary, Treasurer

On your own with the On-Call Book

Party Line

IU achieves first cohesive telecom system