Engineering Commons^™

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 …

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 …

Experimental Study On Filterability Of Leukocytes, Qi Wang

Theses

The filterability of leukocytes treated with A23187, Cytochalasin B, PAF and FMLP and pumped through 5 µm polycarbonate filters at a constant flow rate was examined. The concentration of the four agents was systematically varied. The filtration pressure was continuously recorded for data analysis. The pressure-time curves generally showed multiphasic components, following a small jump step at the beginning of the filtration process. The pressure rise was initially fast (initial faster increased phase, IP) and then rose more slowly (later slower increased phase, LP). The leukocytes treated with A23187 showed increased IP and higher LP values; those which were treated …

Design And Fabrication Of An Implantable Cortical Semiconductor Integrated Circuit Electrode Array, Pierre K. Lefevre

Theses and Dissertations

This research furthered the processing steps of the AFIT 16 by 16 implantable cortical semiconductor integrated circuit electrode array, or brain chip. The areas of interest include the brain chip electron ics, metallization, ionic permeation, and implantation. The electronics and metallization are heavily covered. A high speed, single clock divide-by-two circuit was modified with a reset transistor and cascaded to form a ripple counter. This device had stable operation at specific source voltage and clock voltage and frequency. A 7-stage inverter with 10 unmodified divide-by-two circuits cascaded operated between 1.7 and 8 volts, and between 39 Khz and 1 Mhz, …

A Procedure For Performance Assessment Of Drugs Hypothesized To Be Effective In Controlling Motion Sickness, Zainab N. Ahmed

Theses and Dissertations

The Air Force Institute of Technology (AFIT) is conducting research into the effectiveness of certain drugs for controlling motion sickness. If the drugs are found to be useful, they must still be proven to have no harmful effects on the operator's performance abilities. There are many methods for assessing performance effects of drugs but very little standardization exists. The Unified Tri-Services Cognitive Performance Assessment Battery (UTC-PAB) is a performance assessment method designed to be used by all military branches. This will encourage standardization of drug testing, exchange of data, and comparability of methods. Five tests were chosen from the UTC-PAB …

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

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 …

Ligament Reconstruction : A Biomechanical Cadaveric Test Of Autogenous Repairs And The In Vivo Evaluation Of Synthetic Scaffold Materials, Anne Marie Daly

Theses

The knee joint is the largest and one of the most complex joints in the human body. The anterior cruciate ligament (ACL) is one of the major intra-articular ligaments responsible for controlling and guiding the knee through most of its range of motion and its rupture alters normal joint mechanics.

One objective of this thesis was to determine if two autogenous tissue ACL reconstruction methods were biomechanically equivalent. The first method using the central one-third of the patellar tendon has been used clinically since the early 1960s. The second method utilizes portions of both the semitendinosus and the iliotibial band. …

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 …

Mathematical Modeling And Simulation Of The Progression Of Aids, Anju H. Nagpal

Theses

Acquired Immunodeficiency Syndrome (AIDS) caused by Human Immunodeficiency Virus (HIV) is a pernicious disease acknowledged as a world health problem. One of the major issues in the study of AIDS is understanding the manifestation and the progression of the disease following the transmission of HIV. Unfortunately, the present state of biological knowledge does not yet give us a reliable means of evaluating these phenomena. A simulation approach is, therefore, extremely useful in predicting the various phases of the deteriorating physiological status of the patient. In the present study we have focused on the development of a mathematical model of the …

A Comparison Of Integrated And Differential Estimates Of Flourescent Intensity Profiles Using Digital Video Image Analysis, Langfang Wu

Theses

The dynamics of macromolecular transport across microvascular walls in the hamster cheek pouch have previously been studied by other investigators using fluorescence intravital microscopy. Fluorescein Isothiocyanate labeled Dextrans (FITC-Dx) of 20,000, and 70,000 molecular weight (FITC-Dx-20 and FITC- Dx-70) were used as macromolecular probes. Values of fluorescent intensity were previously recorded on videotape as a function of distance perpendicular to leaking vessels over a period of about 2.5 hr to allow for tracer equilibration in the interstitial space. In this study, these videotapes were played back frame-by-frame and 215x130-pixel windows around each leaking vessel were selected for further analysis of …

Three Dimensional Finite Element Analysis Of A Tibial Ankle Prosthesis, Harrison Philip Crowell Iii

Theses

In this study, three dimensional finite element analysis is used to evaluate and compare partially and fully porous coated tibial components, of an ankle prosthesis, implanted in the distal tibia. The geometry of the distal tibia is determined from measurements of cross sections of a human tibia. From the measurements, solid models of the cancellous and cortical bone are created. A solid model of the tibial component is created and positioned in the solid model of the bone. From the solid model, a finite element model is created for the partially coated case and for the fully coated case. Each …

Biomechanical Analysis Of The Acetabulum And Acetabular Prothesis By Three Dimensional Finite Element Analysis, Mitchell J. Palmer

Theses

A biomechanical analysis modeling methodology of the acetabulum and acetabular prosthesis using three dimensional finite element analysis is presented. A simplified pelvis model is utilized which will yield accurate bone/component interfacial stresses. The SDRC IDEAS software program was used to perform the associated operations. Model generation of the simplified pelvic model and cup, finite element subdivision; material properties, restraints and load modeling are detailed. The model is comprised of 429 isoparametric elements in the simplified pelvis portion and 633 elements in the cup portion. Materials properties and loads are from the literature. The modeling methodology offers the advantages of determining …

Stress Cracking And Breakage Susceptibility As Affected By Moisture Content At Harvest For Four Yellow Dent Corn Hybrids, Curtis Weller, M. R. Paulsen, M. P. Steinberg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Four hybrids of yellow dent com were harvested at three levels of moisture content. After drying, samples were analyzed for stress cracking and susceptibility to breakage in Wisconsin (WBT) and Stein (SBT) breakage testers. Significant differences in stress cracking and breakage susceptibility as determined with the WBT and the SBT were observed among the four hybrids. Breakage susceptibility as measured with the WBT and SBT significantly increased as the harvest moisture increased. Stress cracks increased significantly as harvest moisture increased within the drying air temperatures of 49, 71, and 93° C. WBT breakage susceptibility significantly increased as drying air temperature …

Biocidal Treatment Of Materials With Catechins, Peter E. Laks

Michigan Tech Patents

Sulfide derivatives of catechins derived from condensed tannins have broad spectrum biocidal characteristics. Epicatechin-4-alkylsulfides and cupric complexes thereof containing up to 20, preferably 5 to 15, carbon atoms are particularly effective biocides against wood rotting fungi and gram-positive bacteria. Such sulfides are prepared by reacting condensed tannin, either in the form of a purified tannin extract or comminuted plant tissue, with an appropriate thiol under mild acidic conditions.

Investigation Of The Fluid Dynamics Of Bioprosthetic Heart Valves, Carol A. Calta

Theses

There is a strong connection between altered arterial blood flow and vascular disease. The presence of disturbed flow and/or excessive turbulence is an indication of an abnormality within the cardiovascular system. The examination of cardiovascular fluid dynamics provides insights into the working of the cardiovascular system and ways to improve the design of implantable bioprosthetic valve designs. This investigation examines the fluid flow of arterial systems, and ways to apply this knowledge to the valves implanted into patients.

This thesis involves an investigation of the testing of bioprosthetic valves within simulated left heart flow loops. These systems include pulse duplicators …

Three-Dimensional Stress Analysis Of The Femoral Midshaft Utilizing Computed Tomography And Finite Element Analysis, Peter F. Marion

Theses

Recent advances in computer technology have provided both the medical community and biomedical engineers with a method for noninvasively evaluating the internal structure in a way not previously possible. A three-dimensional finite element model of a midshaft section of the femur was generated, utilizing Computed Tomography scan data. The CT scan data file was introduced into an edge-detection algorithm and a file of geometric edge data was generated. This edge data was introduced into a solid modeling Computer-Aided Engineering software package to produce a three-dimensional solid model. A mesh generation procedure was then used to create a three-dimensional finite element …

Simulation Of Free Radical Reactions In Biology And Medicine: A New Two-Compartment Kinetic Model Of Intracellular Lipid Peroxidation, Charles F. Babbs, Melissa Gale Steiner

Weldon School of Biomedical Engineering Faculty Publications

To explore mechanisms of free radical reactions leading to intracellular lipid peroxidation in living systems, we developed a computational model of up to 109 simultaneous enzymatic and free radical reactions thought to be involved in the initiation, propagation, and termination of membrane lipid peroxidation. Rate constants for the various reactions were obtained from the published literature. The simulation model included a lipid membrane compartment and an aqueous cytosolic compartment, between which various chemical species were partitioned. Lipid peroxidation was initiated by the iron-catalyzed, superoxide-driven Fenton reaction. A "C"-language computer program implemented numerical solution of the steady-state rate equations for concentrations …

A Pressure Sensitive Mat For Measuring Contact Pressure Distributions Of Patients Lying On Hospital Beds, Charles F. Babbs, Joe D. Bourland, George P. Graber, James T. Jones, William E. Schoenlein

Weldon School of Biomedical Engineering Faculty Publications

The authors describe a novel system for sensing and displaying the distribution of contact pressure caused by a patient's lying on a hospital bed. The system includes a flexible, pressure sensitive mat, electronics to activate the mat, a small computer to process data, and a color video display. The present prototypes can sense pressure at 1,536 discrete locations in a rectangular grid of 24 x 64 nodes, each node representing an area of 4 cm2. The computer receives data from each node and displays the results as a false-color map, refreshable every 5 seconds. The pressure sensitive mat itself includes …

Quantitation Of The Hydroxyl Radical By Reaction With Dimethyl Sulfoxide, Melissa G. Steiner, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This investigation was conducted to validate the use of dimethyl sulfoxide (DMSO) as a quantitative molecular probe for the generation of hydroxyl radicals (HO) in aqueous systems. Reaction of HO with DMSO produces methane sulfinic acid as a primary product, which can be detected by a simple calorimetric assay. To evaluate this method for estimating total HO production, we studied three model systems, including the Fenton reaction,  irradiation of water, and ultraviolet photolysis of hydrogen peroxide, for which the theoretical maximum yield of HO could be calculated and compared to measured DMSO oxidation. The results confirm that 0.05 to …

Free Radicals And The Etiology Of Colon Cancer, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This hypothesis paper reviews diverse evidence suggesting that intracolonic production of oxygen radicals may play a role in carcinogenesis. The hypothesis began to evolve when the author made the chance discovery that 1/10,000 dilutions of feces generated detectable quantities of highly reactive hydroxyl radicals (HO). The rate of HO formation, detected using DMSO as a molecular probe, was quite remarkable, corresponding to that which would be produced by over 10,000 rads of gamma irradiation per day, absorbed in the periphery of the fecal mass adjacent to the mucosa. The relatively high concentrations of iron in feces, together with the ability …

Accuracy And Precision Of Computer-Simulated Tissue Temperatures In Individual Human Intracranial Tumours Treated With Interstitial Hyperthermia, J A. Deford, Charles F. Babbs, U H. Patel, N E. Fearnot, J A. Marchosky, C J. Moran

Weldon School of Biomedical Engineering Faculty Publications

Accurate knowledge of tissue temperature is necessary for effective delivery of clinical hyperthermia in the treatment of malignant tumours. This report compares computer-predicted versus measured intratumoral temperatures in 11 human subjects with intracranial tumours, treated with a conceptually simple 'conductive' interstitial hyperthermia system. Interstitial hyperthermia was achieved by the use of parallel arrays of implanted, electrically heated catheters. The tissue was warmed by thermal conduction and blood convection. Simulation of intratumoral temperatures was achieved by solving a modified bioheat transfer equation on a digital computer using a finite difference method. Comparison of intratumoral temperatures from simulations and measured values differed …

Theoretical Basis For Controlling Minimal Tumor Temperature During Interstitial Conductive Heat Therapy, Charles F. Babbs, Neal E. Fearnot, J A. Marchosky, C J. Moran, James T. Jones, T D. Plantenga

Weldon School of Biomedical Engineering Faculty Publications

This paper describes simulation of steady-state intratumoral temperatures achieved by a simple modality of local heat therapy: interstitial treatment with parallel arrays of warmed, conductive heating elements. During “conductive heating” power is directly deposited only in the interstitial probes. Adjacent tissue is warmed by heat conduction. Simulations of interstitial conductive heating involved solution of the bioheat transfer equation on a digital computer using a finite difference model of the treated tissue. The simulations suggest that when the complete temperature distributions for conductive interstitial hyperthermia are examined in detail, substantial uniformity of the temperature distributions is evident. Except for a thin …

Adsorption Of Bromide Tracers Onto Sediment, John E. Gilley, S. C. Finkner, John W. Doran, E. R. Kottwitz

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Information concerning hydraulic parameters on upland areas could be greatly expanded through the use of tracing techniques. If bromide is used as a tracer, adsorption of bromide onto sediment may be of concern. Therefore, a laboratory study was conducted to identify the effects of sediment content and initial bromide concentration on adsorption of bromide for selected soils.
When bromide solutions were used within the appropriate instrument measurement range, neither soil texture, liming, nor sediment content were found to significantly affect adsorption of bromide. In contrast to systems using fluorescent dyes, correction factors for estimating adsorption of bromide are unnecessary. Since …

Approach To Bioremediation Of Contaminated Surface Soils, J. L. Sims, Ronald C. Sims, J. E. Matthews

Biological Engineering Faculty Publications

Biological processes, including microbial degradation, have been identified as critical mechanisms for attenuating organic contaminants during transit through the vadose zone to the groundwater. On-site soil remedial measures using biological processes can reduce or eliminate groundwater contamination, thus reducing the need for extensive groundwater monitoring and treatment requirements. On-site remedial systems that utilize the soil as the treatment system accomplish treatment by using naturally occurring microorganisms to treat the contaminants. Treatment often may be enhanced by a variety of physical/chemical methods, such as fertilization, tilling, soil Ph adjustment, moisture control, etc. The development of a bioremediation program for a specific …

Exposure To Phosphine Gas During Application Of Magnesium Phosphide In Stored Product Warehouses, Mark Anthony Harrison

Theses and Dissertations

The use of phosphine gas requires that respiratory protection be used if exposures exceed the OSHA permissible exposure limit. As with other chemical exposures limits many of the references used to establish occupational health guidelines date back to the 1930’s and 1940’s. This is quite common and is the case with phosphine gas. Initial planning for fumigations involving magnesium phosphide requires that a hazard assessment be performed. Expected worker exposures based on previous monitoring or test data was not readily available. Many current practices and procedures for fumigations are based on recommendations from applicators who used the product in the …

A Simplified Equation For Modeling Sediment Transport Capacity, S. C. Finkner, M. A. Nearing, G. R. Foster, John E. Gilley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Sediment transport capacity for shallow overland flow was represented as a quadratic function of downslope distance using the assumption of a linear increase in overland flow discharge with downslope distance and an approximation to the Yalin equation for sediment transport capacity. The simplified equation for sediment transport applies to complex topography having uniform soil and management characteristics. The simplified equation accurately approximated the Yalin equation when calibrated using the average of the hydraulic shear stresses at the end of a constant slope reference profile and the end of the actual profile. The simplified equation is useful in deriving closed-form solutions …

On The Orders Of Magnitude Of Epigenic Dynamics And Monoclonal Antibody Production, Joanne M. Savinell (Belovich), Gyun Min Lee, Bernhard O. Palsson

Chemical & Biomedical Engineering Faculty Publications

The hybridoma cell's maximum capacity for monoclonal antibody (MAb) production is estimated to be 2300–8000 MAb molecules/cell/s, using measured rates of transcription and translation, and the limitations imposed by the size of the polymerase molecule and the ribosome. Nearly all the production rates reported in the literature fall into or below this range of production rates. Data from batch cultures of hybridomas demonstrate a constant specific rate of MAb production until the time integral of the viable cell concentration reaches about 10⁸ cells · h/cm³. At this point, some essential nutrients from the standard media …

Irrigation Soybeans By Growth Stages In Nebraska, N. L. Klocke, Dean E. Eisenhauer, James E. Specht, Roger Wesley Elmore, Gary W. Hergert

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigated soybean production in Nebraska spans a region with diverse soils and climates. Irrigators can easily adopt irrigation scheduling using a stage of growth for timing applications. However, simplifying assumptions, including soil water holding capacity, rainfall, stored soil water, and adequate irrigation system capacity, are implicit in the development of stage of growth irrigation scheduling recommendations. Reliance on these can lead to misapplication of irrigation water.
This project tested irrigation scheduling techniques for indeterminate soybean production in Nebraska, with stage of growth indicating the initiation of irrigation. The range of soils and climate in the study area gave a range …

A Comparison Of The Fracture Toughness, Hardness, Impact Strength, And Thermal Expansion Of Two Dental Porcelains, Nancy Maignon

Theses

Dental Porcelains are known to be very brittle materials. Ongoing research is being undertaken to obtain a porcelain of optimum strength. A recent development in this field is the new porcelain Optec HSP.

In this comparative study, a series of mechanical test were performed on both Optec HSP and Ceramco II.

An indentation technique was used to calculate the hardness and fracture toughness, the Izod method with a 1 ft-lb pendulum was used to obtain the impact strength, and the thermal expansion was calculated with the Dupont thermal analyser.

For each material, a sample size of five and twenty specimens …