Engineering Commons^™

Image Analysis And The Effect Of Molecular Orientation On Degrading Lactide Polymer Films, K. J. L. Burg, M. Laberge, D. L. Powers, S. W. Shalaby

Cells and Materials

Absorbable polylactide films were studied in order to observe the effect of orientation on the resulting hydrolytic degradation pattern. Two types of polylactide films with two levels of molecular orientation were studied, during a nine month exposure to a phosphate buffered solution at 37°C. The films were sectioned and quantified as to void area, birefringence area, and intensity of birefringence using a microscope and an image analysis software package. The results, obtained using an analysis of variance, showed that the orientation played a significant role in the degradation pattern of the polylactide films, either decreasing or causing no change in …

Biomimetic Habitats For Cells: Ordered Matrix Deposition And Differentiation In Gingival Fibroblasts Cultured On Hydroxyapatite Coated With A Collagen Analogue, Rajendra S. Bhatnagar, Jing Jing Qian, Anna Wedrychowska, Eric Dixon, Nancy Smith

Cells and Materials

In tissues, cells attach and migrate on collagen. Interaction with collagen modulates cell proliferation and differentiation. We propose that similar environments may be constructed by immobilizing collagen-derived cell-binding peptides in a three-dimensional (3-D) template. We identified a cell binding domain of type I collagen and showed that a 15-residue synthetic analogue (P-15) binds cells with high affinity. In the present study, we compared the behavior of human gingival fibroblasts (HGF) in culture on hydroxyapatite (HA) and on HA-P-15. HGF cultured on HA formed sparse monolayers with little order and deposited a scant matrix. HGF on HA-P-15 formed highly oriented 3-D …

Derivation Of Equations Of Motion For A Four Link Robotic Leg For A Walking Vehicle, Andrew B. Wright

Journal of the Arkansas Academy of Science

A four degree of freedom leg for a walking robot has been modeled using Newton's method. Unlike robot manipulators, which have a fixed base, a leg model must include inertial forces due to base motion. These forces have been included in the formulation. These equations can be used for design, simulation, and control. The inverse kinematics for this leg are also presented. This allows the joint angles to be computed from a desired foot-hold position.

Square Planar Monopole Antenna, Max Ammann

Conference papers

A planar monopole may be realised by replacing the wire element of a conventional monopole with a planar element. In this case, the planar element which is square, is located above a groundplane and fed using an SMA connector as illustrated. The square monopole has a simple geometry and a smaller bandwidth compared to the circular-disc monopole. However, it is still a broadband antenna with a typical impedance bandwidth of 75 % at S band. This broadband antenna shows a constant radiation pattern over the impedance bandwidth. A simple formula for the frequency corresponding to the lower edge of the …

Production Of Biogenic Mn Oxides By Leptothrix Discophora Ss-1 In A Chemically Defined Growth Medium And Evaluation Of Their Pb Adsorption Characteristics, Yarrow M. Nelson, Leonard W. Lion, William C. Ghiorse, Michael L. Shuler

Civil and Environmental Engineering

Biogenic Mn oxides were produced by the bacterium Leptothrix discophora SS-1 (= ATCC 3182) in a chemically defined mineral salts medium, and the Pb binding and specific surface area of these oxides were characterized. Growth of SS-1 in the defined medium with pyruvate as a carbon and energy source required the addition of vitamin B₁₂. Complete oxidation of Mn(II) within 60 h required the addition of ≥0.1 μM FeSO₄. Pb adsorption isotherms were determined for the biogenic Mn oxides (and associated cells with their extracellular polymer) and compared to the Pb adsorption isotherms of cells and …

District Application Of Hand Held Data Recorder Technology, Stuart Styles, Charles M. Burt

BioResource and Agricultural Engineering

A hand held data recorder (HHDR) enables a district to collect field data in a quick and virtually error-free manner. These units can be used to scan bar code location/equipment identifiers or the operator can manually key in this information followed by the current data. Some HHDRs can be programmed with error checking routines that prompt the operator when an entry is inconsistent with regards to the previous reading from that location. Each entry includes a time and date stamp. When the operator has collected all of the data for the day or for a route, the data is downloaded …

Simple, Portable Water Level Monitoring Package, Charles M. Burt, Stuart Styles

BioResource and Agricultural Engineering

Electronic water level sensing equipment is becoming increasingly important for the implementation of water conservation programs in irrigation districts. A need has risen for information on costs, advantages/disadvantages, required support equipment, and required maintenance for the various options. For this reason, the Water Conservation Office of the Mid-Pacific Region of the USBR contracted with the Cal Poly ITRC to conduct a study on water level sensors and dataloggers and to produce a report.

One application covered in the water level sensor and datalogger report is the need to have a simple, portable water level monitoring package. This paper supplements the …

Santa Clara Magazine, Volume 41 Number 3, Winter 1999, Santa Clara University

Santa Clara Magazine

8 - NOT WITH MY DAUGHTER, YOU DON'T! By Susan Fry. An SCU psychologist explores the correlation between dating and self-esteem for adolescent girls.

12 - COMMON GROUND FOUND By Tamara Straus. SCU has a new partner: the Smithsonian Center for Mate rials Research and Education. Together they are pursuing what a top-notch 21st-century education will require.

16 - THE NEW VOICES OF SANTA CLARA By Nichole Pichel, Miguel Legarreta, Charlene Abalos, Audrey Bilczo, and Jennifer Farris. Five incoming students share their experience of building values in a world of uneven prosperity, opportunity, and choice.

A Literature Review Of The Effect Hot Reduction Has On The Structure, Mechanical Properties, And Fatigue Performance Of Continuous Cast Steel, Stanley J. Syhlman

Graduate Student Work

The purpose of the investigation is to review the published literature concerning investigatlons of the effects of hot reduction and other factors have on the structure, properties, and performance of continuously cast steel products. Of principle interest is the recognition of a minimum reduction ratio needed to provide steel with acceptable design options for industrial customers. The minimum reduction or rolling ratio is the cross-sectional area of the cast billet divided by the corresponding area of the final rolled product required to assure the breakdown of the as cast structure, and the attainment of satisfactory mechanical properties. The investigation is …

Meade: A Modular, Extensible, Adaptable Design Environment For Asic And Fpga Development, Gary Spivey

Faculty Publications - Department of Electrical Engineering and Computer Science

We present MEADE, a Modular, Extensible, Adaptable Design Environment. MEADE has been developed to answer the need for an adaptive design framework for encapsulation of Computer Aided Design (CAD) tools and management of the massive amounts of data associated with the design process. Other frameworks have existed but lacked the critical open source requirement that enables rapid adaptation to a rapidly advancing design methodology. While the initial application and development of MEADE is targeted toward ASIC and FPGA design, the MEADE engine can be easily adapted to abstract any procedural application.

MEADE allows the definition of procedures, which are defined …

Report Of The Poplar Working Group, Steve Strauss

United States Department of Energy: Publications

Poplars consist of all species of the genus Populus, including cottonwoods, aspens, and the many interspecies hybrids in common use (Dickmann and Stuart 1983). Our working group focused on the fungal pathogens, arthropod herbivores, and weed competitors of Populus in the United States. However, bacterial and viral diseases of Populus are significant in Europe, and genetic engineering approaches toward their control or management are being studied. The key aspects of poplar biology important to understanding the use of pest resistance genes are described below.

2h Solid-State Nmr Investigation Of Terephthalate Dynamics And Orientation In Mixed-Anion Hydrotalcite-Like Compounds, Robert S. Maxwell, Ravi K. Kukkadapu, James E. Amonette, Herman Cho

United States Department of Energy: Publications

The dynamics and orientations of interlayer terephthalate (TA) anions in mixed-anion hydrotalcite-like compounds [Mg_1-x Al_x(OH)₂](A_yB_1-y)_x/2•nH₂O, where A = p-C₆D₄(COO)₂^2- and B ) CO₃^2-] were investigated by ²H variable-temperature solid-state nuclear magnetic resonance (NMR) spectroscopy. Two dominant 003 d spacings, 7.6 and 14.2 Å, were observed by X-ray diffraction (XRD) in these samples, suggesting that there were at least two interlayer environments. Over the range of layer charges studied (0.37 ≥ x ≥ 0.29), the intensity …

Metal Oxide Surfaces And Their Interactions With Aqueous Solutions And Microbial Organisms, Gordon E. Brown Jr., Victor Henrich, William Casey, David Clark, Carrick Eggleston, Andrew Felmy Andrew Felmy, D. Wayne Goodman, Michael Gratzel, Gary Maciel, Maureen I. Mccarthy, Kenneth H. Nealson, Dimitri Sverjensky, Michael Toney, John M. Zachara

United States Department of Energy: Publications

During the past decade, interest in chemical reactions occurring at metal oxide-aqueous solution interfaces has increased significantly because of their importance in a variety of fields, including atmospheric chemistry, heterogeneous catalysis and photocatalysis, chemical sensing, corrosion science, environmental chemistry and geochemistry, metallurgy and ore beneficiation, metal oxide crystal growth, soil science, semiconductor manufacturing and cleaning, and tribology. The metal oxide-aqueous solution interface is reactive due to acid-base, ligand-exchange, and/or redox chemistry involving protons (hydronium ions), hydroxyl groups, aqueous metal ions, and aqueous organic species and also complexes among these species. Interfacial localization of those species (adsorption) may result from electrostatic, …

Climate Change Impacts On The Potential Productivity Of Corn And Winter Wheat In Their Primary United States Growing Regions, Robert Brown, Norman Rosenberg

United States Department of Energy: Publications

We calculate the impacts of climate effects inferred from three atmospheric general circulation models (GCMs) at three levels of climate change severity associated with change in global mean temperature (GMT) of 1.0, 2.5 and 5.0 _C and three levels of atmospheric CO₂ concentration ([CO₂]) – 365 (no CO2 fertilization effect), 560 and 750 ppm – on the potential production of dryland winter wheat (Triticum aestivum L.) and corn (Zea mays L.) for the primary (current) U.S. growing regions of each crop. This analysis is a subset of the Global Change Assessment Model (GCAM) which has …

Below-Ground Respiratory Responses Of Sugar Maple And Red Maple Saplings To Atmospheric Co2 Enrichment And Elevated Air Temperature, Nelson Edwards, Richard Norby

United States Department of Energy: Publications

The research described in this paper represents a part of a much broader research project with the general objective of describing the effects of elevated [CO₂] and temperature on tree growth, physiological processes, and ecosystem-level processes. The specific objective of this research was to examine the below-ground respiratory responses of sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) seedlings to elevated atmospheric [CO₂] and temperature. Red maple and sugar maple seedlings were planted in the ground in each of 12 open-top chambers and exposed from 1994 through 1997 to ambient air …

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …

Bolt Bearing Behavior Of Engineered Wood Composites, Stephen J. Carstens, David Pollock

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The goal of this research was to gain a better understanding of the bolt bearing behavior of engineered wood composites made from yellow poplar lumber. Lumber specimens included in this study were laminated veneer lumber, strandbased lumber, yellow poplar lumber, and Douglas-fir larch lumber. Testing followed the half-hole and full-hole configuration as set forth in ASTM Standard D5764 (1998).

In a previous study by Wilkinson (1991), a strong correlation was shown between bearing strength perpendicular to grain and bolt diameter. This study supports Wilkinson's finding for bearing strength perpendicular-to-grain based on the half hole test configuration. Other findings in this …

Fuzzy Systems Are Universal Approximators For A Smooth Function And Its Derivatives, Vladik Kreinovich, Hung T. Nguyen, Yeung Yam

Departmental Technical Reports (CS)

One of the reasons why fuzzy methodology is successful is that fuzzy systems are universal approximators, i.e., that we can approximate an arbitrary continuous function within any given accuracy by a fuzzy system. In some practical applications (e.g., in control), it is desirable to approximate not only the original function, but also its derivatives (so that, e.g., a fuzzy control approximating a smooth control will also be smooth). In our paper, we show that for any given accuracy, we can approximate an arbitrary smooth function by a fuzzy systems so that not only the function is approximated within this accuracy, …

Time-Bounded Kolmogorov Complexity May Help In Search For Extra Terrestrial Intelligence (Seti), Martin Schmidt

Departmental Technical Reports (CS)

One of the main strategies in Search for Extra Terrestrial Intelligence (SETI) is trying to overhear communications between advanced civilizations. However, there is a (seeming) problem with this approach: advanced civilizations, most probably, save communication expenses by maximally compressing their messages, and the notion of a maximally compressed message is naturally formalized as a message x for which Kolmogorov complexity C(x) is close to its length l(x), i.e., as a "random" message. In other words, a maximally compressed message is indistinguishable from the truly random noise, and thus, trying to detect such a message does not seem to be a …

Extending T-Norms Beyond [0,1]: Relevant Results Of Semigroup Theory, Yeung Yam, Vladik Kreinovich

Departmental Technical Reports (CS)

Originally, fuzzy logic was proposed to describe human reasoning. Lately, it turned out that fuzzy logic is also a convenient approximation tool, and that moreover, sometimes a better approximation can be obtained if we use real values outside the interval [0,1]; it is therefore necessary to describe possible extension of t-norms and t-conorms to such new values. It is reasonable to require that this extension be associative, i.e., that the set of truth value with the corresponding operation form a semigroup. Semigroups have been extensively studied in mathematics. In this short paper, we describe several results from semigroup theory which …

Missouri River Stream Bank Erosion Assessment Gavins Point Dam To Ponca, Ne

United States Army Corps of Engineers, Omaha District

The purpose of this report is to document the methodology and results obtained from a study of bank erosion along the Missouri River between Gavins Point Dam (RM 805.2) and Ponca, Nebraska (RM 752.3). Three (3) periods were studied: 1) August 1985 to August 1995, a time span of 10 years and; 2) from August 1995 and August 1997, a time span of 2 years. This study has been prepared by HDR Engineering, Inc. (HDR) under Contract No. DACW 45-97-D-0007 (Delivery Order 0019) for the Omaha District of the U.S. Army Corps of Engineers.

Practical Hints For The Layout And Construction Of 10,000 M3 Circular Dams, Terry Babbington, J S. Addison

Bulletins 4000 -

These notes and illustrations have been compiled to assist earthmovers in the construction of circular excavated earth tank dams, with pipe inlets. Construction techniques tend to evolve over time, so the methods described in this publication will not be definitive, but, they may improve efficiency of construction in the interim. Although the example used in these notes refers to 10,000 m3 dams, the construction techniques, using a bulldozer, described here equally apply to dams of any volume of similar design. Only dimensions will vary. earthmovers using a scarper together with a bulldozer should be able to extract useful information from …

Analysis Of Ductile To Cleavage Transition In Part-Through Cracks Using The Cell Model Incorporating Statistics, Xiaosheng Gao, J. Faleskog, C. Fong Shih

Mechanical Engineering Faculty Research

This paper describes an approach to study ductile/cleavage transition in ferritic steels using the methodology of a cell model for ductile tearing incorporating weakest link statistics. The model takes into account the constraint effects and puts no restriction on the extent of plastic deformation or amount of ductile tearing preceding cleavage failure. The parameters associated with the statistical model are calibrated using experimental cleavage fracture toughness data, and the effect of threshold stress on predicted cleavage fracture probability is investigated. The issue of two approaches to compute Weibull stress, the ‘history approach’ and the ‘current approach’, is also addressed. The …

Emerald: A Low Cost Spacecraft Mission For Validating Formation Flying Technologies, Robert J. Twiggs, Jonathan How, Freddy Pranajaya, Bryan Palmintier

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs, Robert Twiggs, Jonathon How, Freddy Pranajaya, and Bryan Palmintier titled "EMERALD: A Low Cost Spacecraft Mission for Validating Formation Flying Technologies" from 1999.

The Role Of Surface Roughness For Implant Incorporation In Bone, A. Wennerberg

Cells and Materials

A careful topographical characterization is important for reliable interpretation of the role of implant surface roughness in bone incorporation. In this paper, the currently available measuring instruments and evaluation techniques are described and discussed first, than literature on the role of surface roughness for cell and bone tissue reactions in vitro and, with special emphasis, the in vivo studies are reviewed. Finally, the results from a series of the authors own animal studies evaluating screw-shaped implants with different surface roughnesses are summarized. The results demonstrated firmer bone fixation for blasted implants than for turned ones. A blasted surface with an …

Wax Yield Of Grain Sorghum (Sorghum Bicolor) As Affected By Mechanical Harvesting, Threshing, And Handling Methods, K. R. Lochte-Watson, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Wax is found on the outer layer of the grain sorghum (Sorghum bicolor) kernel. Current harvesting and handling techniques cause abrasion and breakage, thereby potentially reducing wax yield from sorghum kernels. The purpose of this study was to determine wax yield of sorghum after mechanical harvesting and handling and to compare wax yield of whole and broken sorghum kernels. Combine threshing and auger conveying of grain caused abrasion and breakage, which reduced the wax yield by 5%. The monitored process in this experiment included a cleaning system which reduced the amount of broken kernels and sorghum particles, increasing …

Belts Vs Tires, Belts Vs Belts, Tires Vs Tires, Leonard L. Bashford, Michael F. Kocher

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Tractive performance comparisons among two different width rubber belt tracks, 46 cm (18 in.) and 81 cm (32 in.) wide, and two different size rear tires, 710/70R38 and 18.4R46, were made on two different surface conditions. The belts were tested on a Caterpillar 55 tractor equipped with the Mobil-trac™ system and the tires on a John Deere 8400 mechanical front-wheel-drive (MFWD) tractor. The performance tests were completed on two surfaces, one being a non-tilled wheat stubble field and the second, the wheat stubble field tilled approximately 23 cm (9 in.) deep with a Noble blade sweep. Performance comparisons using tractive …

Seepage Characteristics And Hydraulic Properties Of A Feedlot Runoff Storage Pond, David B. Parker, Dean E. Eisenhauer, Dennis D. Schulte, John A. Nienaber

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water and chemical transport were investigated beneath a 22-year-old beef feedlot runoff storage pond. Soil and sludge samples were collected from 14 borings to 6.1-m depths in a cross-section across the pond. The soils consisted of silt loam and clay loam, and the groundwater level was about 30 m beneath the land surface. Soil samples were analyzed for pH, NO₃-N, NH₄-N, Cl, P, K, SO₄-S, TKN, and organic matter. Physical and hydraulic properties were measured on undisturbed samples of soil and sludge to compare saturated hydraulic conductivity, moisture release characteristics, and bulk density. Saturated …

Model Updating By Adding Known Masses And Stiffnesses, Philip D. Cha, Lisette G. De Pillis

All HMC Faculty Publications and Research

New approaches are developed to update the analytical mass and stiffness matrices of a system. By adding known masses to the structure of interest, measuring the modes of vibration of this mass-modified system, and finally using this set of new data in conjunction with the initial modal survey, the mass matrix of the structure can be corrected. A similar approach can also be used to update the stiffness matrix of the system by attaching known stiffnesses. Manipulating the mass and stiffness correction matrices into vector forms, the connectivity information can be enforced, thereby preserving the physical configuration of the system, …