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Cal Poly Magazine

No abstract provided.

Report On Proposals Submitted And Funded, July 1, 2006 - June 30, 2007, Office Of Research And Sponsored Programs. Morehead State University.

Office of Research and Sponsored Programs Reports and Publications

Report on Proposals Submitted and Funded for July 1, 2006 - June 30, 2007.

Requests Of Brown By Lc Classification: July 2007, Ruth E.. Souto

HELIN Monthly Loan Statistics

Requests of Brown from other HELIN libraries - July 2007

Scale Deposits In Porous Media And Their Removal By Edta Injection, J. Moghadasi, H. Müller-Steinhagen, M. Jamialahmadi, A. Sharif

Heat Exchanger Fouling and Cleaning VII

Formation damage has been observed in several oil reservoirs and production equipment in Iranian oil fields. Laboratory and field testing confirmed that the primary cause of damage was the build-up of calcium carbonate, calcium sulfate and strontium sulfate scale either in the perforation tunnels or in the formation sandstone nears the wellbore. Conventional acid treatments could dissolve this scale, but scale precipitation from the spent acid caused rapid productivity decline. A scale removal treatment with Na2H2EDTA has been developed that can effectively dissolve scale and chelate the dissolved metal ions. Chelation of the dissolved scale prevents scale reprecipitation. This study …

Observation Of An Isokinetic Temperature And Compensation Effect For High Temperature Crude Oil Fouling, C. A. Bennett, R. S. Kistler, K. Nangia, W. Al-Ghawas, N. Al-Hajji, A. Al-Jemaz

Heat Exchanger Fouling and Cleaning VII

The initial fouling rates of four crude oils were determined at a nominal bulk temperature of 315 °C, an initial heated wall shear stress of 13 Pa, and initial surface temperatures between 375 and 445 °C. These initial fouling rates ranged from 1.3(10-6) to 7.8(10-5) m2 K/kJ. Corresponding Arrhenius plots were linear with the initial fouling rates passing through an isokinetic temperature of 407.5 °C. A plot of the natural logarithm of the preexponential factors (7.6(104) – 5.2(1015) m2 K/kJ) versus the apparent activation energies (128 – 269 kJ/mol) was also linear, confirming the validity of the isokinetic temperature and …

Experiments And Modelling Of Calcium Sulphate Precipitation Under Sensible Heating Conditions: Initial Fouling And Bulk Precipitation Rate Studies, F. Fahiminia, A. P. Watkinson, N. Epstein

Heat Exchanger Fouling and Cleaning VII

Crystallization of calcium sulphate, an inverse solubility salt, on a heated surface under sensible heating conditions has been studied. A temperature measurement technique was employed to detect initial fouling rates. Fouling experiments were carried out to determine how process variables such as surface temperature and velocity affect the initial fouling rates of calcium sulphate scaling. Experimental results show that, at a given surface temperature, there exists a maximum initial fouling rate for a range of fluid velocities. Also, this maximum rate and the fluid velocity at which it occurs both increase as the surface temperature increases. These observations are all …

Modelling Of Particulate Fouling On Heat Exchanger Surfaces: Influence Of Bubbles On Iron Oxide Deposition., D.H. Lister, F.C. Cussac

Heat Exchanger Fouling and Cleaning VII

Studies of iron oxide deposition on Alloy-800 heatexchanger tubes have been part of a continuing research program at the University of New Brunswick; the present work formulates mechanisms for the effect of bubbles on deposition in water under boiling conditions. To supplement results from earlier deposition experiments in a fouling loop at UNB, measurements of bubble frequency and departure diameter as a function of heat flux were performed. High-speed movies of bubbling air/water systems indicated that a pumping action moved particles from adjacent areas at the surface to bubble nucleation sites. To explain the observations, the model considers deposition and …

Simultaneous Consideration Of Flow And Thermal Effects Of Fouling In Crude Oil Preheat Trains, G.T. Polley, A. Morales Fuentes, D.I. Wilson

Heat Exchanger Fouling and Cleaning VII

Given models linking flow resistance and fouling resistance it becomes possible to simulate the effects of fouling on the hydraulic performance of a refinery pre-heat train. Such a simulation has been used here to identify when plant throughput will be limited by pressure drop; how throughput can be improved through the cleaning of individual exchangers and groups of exchangers; and how much production can be maintained when individual exchangers are taken off-line. Determination of better operating strategy requires a simulation of both hydraulic and thermal performance. In this paper we implement a pragmatic linked model and consider the results from …

A Lagrangian Particle Cfd Post-Processor Dedicated To Particle Adhesion/Deposition, M. Losurdo, C. Bertrand, H. Spliethoff

Heat Exchanger Fouling and Cleaning VII

In the past few years the use of biomass in power plants has grown dramatically. As a result of this action fouling and slagging in co-firing biomass facilities have turned out to play a critical role in the efficiency of such facilities. Efficient and effective methods are therefore needed to control fouling to an acceptable level and to prevent economic losses due to reduced furnace thermal efficiency, increased maintenance or even unscheduled outages. Numerical prediction of the impact of deposit properties has proved itself to be a successful strategy to both evaluate changes in the facility performance and to investigate …

Effect Of Thermal Contact Resistance On The Heat Transfer In Plate Finned Tube Heat Exchangers, D. Taler

Heat Exchanger Fouling and Cleaning VII

Plate fin-and-tube heat exchangers are made by inserting oval tubes through sheet metal strips with stamped holes and then expanding the tubes slightly to cause pressure at the tube-to-strip contacts. The gap between the fin base and the outer tube surface may be filled with air or corrosion products causing a decline in the ability of plate fins to transfer heat. The contact resistance must be accounted for in the design and performance calculations of heat exchangers. In this paper, the thermal contact resistance of the fin-to-tube attachment is estimated from the condition that the dimensionless correlations for the Colburn …

Intelligent Discrimination Model To Identify Influential Parameters During Crystallisation Fouling, M.R. Malayeri, H. Müller-Steinhagen

Heat Exchanger Fouling and Cleaning VII

The introduction of redundant independent variables into any function approximation model, or the neglect of important variables, may result in a correlation with poor prediction and reduced reliability. This paper demonstrates that a novel integrated model of neural networks and genetic algorithms can deal with this problem robustly with good accuracy, while be far less time-consuming compared to lengthy conventional models Furthermore, a redundant variable input was imposed to the model to discern if the approach could identify it among other important variables. Genetic algorithms were exploited as a powerful optimisation tool for the selection of best set of inputs …

Cleaning Monitoring Using Controlled Nano-Vibrations, A. Pereira, J. Mendes, L.F. Melo

Heat Exchanger Fouling and Cleaning VII

The monitoring of fouling and cleaning has become very important in order to optimize production cycles, to increase the quality of the final product and to reduce environmental impacts. The aim of the study here presented was to use the MSS – Mechatronic Surface Sensor, to detect the cleaning end-point of hair shampoo removal under different cleaning conditions. It was found that this new monitoring tool was able to clearly identify when the equipment was cleaned, producing different cleaning curves for different cleaning conditions.

Isomorphisms Of Elliptic Curves Over Extensions Of Finite Fields, Mathew Niemerg

Mathematical Sciences Technical Reports (MSTR)

Our main interest lies in exploring isomorphisms of elliptic curves. In particular, we focus on two curves defined over a base field and look at which extension fields the curves are isomorphic over. Elliptic curves have a fascinating structure behind them. This structure allows for much to be explored and studied.

Double Integral Calculus Of Variations On Time Scales, Gusein Sh. Guseinov, Martin Bohner

Mathematics and Statistics Faculty Research & Creative Works

We consider a version of the double integral calculus of variations on time scales, which includes as special cases the classical two-variable calculus of variations and the discrete two-variable calculus of variations. Necessary and sufficient conditions for a local extremum are established, among them an analogue of the Euler-Lagrange equation.

Emeriti News, Summer 2007, Emeriti Council

Emeriti News

Contents from Volume XII, Number 2:

• Coming Attractions
• Exploring Our Campus
• Emeriti Flu Clinic
• Emeriti Theatre Matinee
• Election Results: The 2007-2008 Emeriti Council
• The Emeriti Council Webpage
• The Year in Review
• Invest in Your Health

Reliability Of Concrete Masonry Unit Walls Subjected To Explosive Loads, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

This study discuses the development of a procedure that can be used to assess the reliability of concrete masonry unit infill walls subjected to personnel-delivered blast loads. Consideration is given to maintain reasonable computational effort for both the structural analysis and reliability models. Blast load and wall resistance models are developed based on experimental and analytical data, and resistance is evaluated with a large strain, large displacement transient dynamic finite element analysis. A sensitivity analysis is conducted to identify significant random variables and a reliability analysis conducted with a feasible level of computational effort. Reliability indices are estimated for two …

Marshall Magazine Summer 2007, Marshall University

Marshall Magazine

No abstract provided.

Free Will, Glenn Sheldon

Harpur Palate: a Literary Journal

page 155

Santa Clara Magazine, Volume 49 Number 1, Summer 2007, Santa Clara University

Santa Clara Magazine

8 - A CENTURY OF BRONCO BASKETBALL, By Jed Mettee and Steven Boyd Saum. Celebrating the first hundred seasons.

12 - A FAMILY SHOW By Steven Boyd Saum. Meet new men's basketball coach Kerry Keating.

14 - A SPACE THAT TALKS TO NATURE By Miriam Schulman. A team of SCU students aim to win the Department of Energy's Solar Decathlon. And save the planet.

19 - EPITAPH FOR THE JOURNEY A poem by Paul Mariani.

22 - THE BUZZ ABOUT SUSTAINABILITY By John Farnsworth. When we talk about "sustainability," what are we really talking about?

26 - THE GREEN TAX …

Fractalized Cyclotomic Polynomials, David P. Roberts

Mathematics Publications

For each prime power p^m, we realize the classical cyclotomic polynomial Φ_p^m(x) as one of a collection of 3^m different polynomials in Z[x]. We show that the new polynomials are similar to Φ_p^m(x) in many ways, including that their discriminants all have the form ±p^c. We show also that the new polynomials are more complicated than Φ_p^m(x) in other ways, including that their complex roots are generally fractal in appearance.

Supporting Lexical Ontology Learning By Relational Exploration, Sebastian Rudolph, Johanna Volker, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Designing and refining ontologies becomes a tedious task, once the boundary to real-world-size knowledge bases has been crossed. Hence semi-automatic methods supporting those tasks will determine the future success of ontologies in practice. In this paper we describe a way for ontology creation and refinement by combining techniques from natural language processing (NLP) and formal concept analysis (FCA). We point out how synergy between those two fields can be established thereby overcoming each other’s shortcomings.

Patterns Of Photometric And Chromospheric Variation Among Sun-Like Stars: A 20 Year Perspective, G. Wesley Lockwood, Brian A. Skiff, Gregory W. Henry, Stephen M. Henry, Richard R. Radick, Sallie L. Baliunas, Robert A. Donahue, Willie Soon

Information Systems and Engineering Management Research Publications

We examine patterns of variation of 32 primarily main-sequence Sun-like stars [selected at project onset as stars on or near the main sequence and color index 0.42 ≤ (B - V) ≤ 1.4], extending our previous 7-12 yr time series to 13-20 yr by combining Strömgren b, y photometry from Lowell Observatory with similar data from Fairborn Observatory. Parallel chromospheric Ca II H and K emission data from the Mount Wilson Observatory span the entire interval. The extended data strengthen the relationship between chromospheric and brightness variability at visible wavelengths derived previously. We show that the full range of photometric …

Effects Of Item Positions On Their Difficulty And Discrimination : A Study In Pisa Science Data Across Test Language And Countries, Luc T. Le

OECD Programme for International Student Assessment (PISA)

This study was based on a four-cluster rotation design of 13 linked test booklets from PISA 2006 science data. It investigated effects of item positions on their difficulty and discrimination parameter estimates obtained from one and two parameter IRT Partial Credit models. The analyses were done separately for 57 test language groups from 53 countries with a total of about 340,000 students.

The results revealed that for all of the test language groups the items tended to become more difficult when they were located later in the test. However, a high linear relationship between the item difficulty estimates by the …

Gen Ms 20 Jane And Robert Pickett Papers Finding Aid, Daniel Draper

Search the General Manuscript Collection Finding Aids

Description:

Robert Stanley Pickett and Jane Niles Pickett attended Gorham State Teacher's College from 1949 to 1953. The Papers contain materials concerning academic, athletic and student social activities at Gorham State Teacher's College in the early 1950s, including a scrapbook and newspaper clippings.

Date Range:

1949-1953

Size of Collection:

0.5 ft.

The Learning Marketspace, July 2007, Bob Heterick, Carol Twigg

The Learning MarketSpace (4/03 - 4/14)

No abstract provided.

Inter-Dna Attraction Mediated By Divalent Counterions, Xiangyun Qiu, Kurt Andresen, Lisa W. Kwok, Jessica S. Lamb, Hye Yoon Park, Lois Pollack

Physics and Astronomy Faculty Publications

Can nonspecifically bound divalent counterions induce attraction between DNA strands? Here, we present experimental evidence demonstrating attraction between short DNA strands mediated by Mg2 ions. Solution small angle x-ray scattering data collected as a function of DNA concentration enable model independent extraction of the second virial coefficient. As the [Mg2] increases, this coefficient turns from positive to negative reflecting the transition from repulsive to attractive inter-DNA interaction. This surprising observation is corroborated by independent light scattering experiments. The dependence of the observed attraction on experimental parameters including DNA length provides valuable clues to its origin.

Fixed Points Of Abelian Actions, John Franks, Michael Handel, Kamlesh Parwani

Faculty Research and Creative Activity

We prove that if $\F$ is an abelian group of $C^1$ diffeomorphisms isotopic to the identity of a closed surface $S$ of genus at least two then there is a common fixed point for all elements of $\F.$

Macalester Today Summer 2007, Macalester College

Macalester Today

No abstract provided.

Handwriting: Should Formal Instruction In Handwriting Be Taught To Elementary Students?, Cathleen Rutter

Education 589 Projects

Having taught students Language Arts from 2nd grade through sophomore year of high school, I have encountered numerous samples of handwriting, with great variance in their legibility. It has caused me frustration as a beginning teacher trying to decipher what has actually been written and just what the student was trying to convey to myself, as their teacher. In some cases I have graded a spelling test, marked words incorrect because I could not read the letters in the word. But then, because I felt that the student has mastered the spelling of a given word, I had the student …

Electronic, Magnetic And Transport Properties Of Rare-Earth Monopnictides, Chun-Gang Duan, Ildar F. Sabiryanov, Wai-Ning Mei, Peter A. Dowben, Sitaram Jaswal, Evgeny Y. Tsymbal

Peter Dowben Publications

The electronic structures and magnetic properties of many rare-earth monopnictides are reviewed in this article. Possible candidate materials for spintronics devices from the rare-earth monopnictide family, i.e. high polarization (nominally half-metallic) ferromagnets and antiferromagnets, are identified. We attempt to provide a unified picture of the electronic properties of these strongly correlated systems. The relative merits of several ab initio theoretical methods, useful in the study of the rare-earth monopnictides, are discussed. We present our current understanding of the possible half-metallicity, semiconductor–metal transitions, and magnetic orderings in the rare-earth monopnictides. Finally, we propose some potential strategies to improve the magnetic and …