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Acuta Enews December 2011, Vol 40, No. 12 Dec 2011

Acuta Enews December 2011, Vol 40, No. 12

ACUTA Newsletters

In This lssue

Nominate a Colleague for ACUTA Ruth A. Michalecki Leadership Award

From ACUTA Headquarters: What's New?................ Corinne Hoch, Executive Director

Coping with the Next Ethernet, IEEE 802.3ba ......Gary Audin, Delphi, lnc.

View 6 Sessions from the Fall Seminar

Helping Young Professionals Get Professional Development....... Jana McDonald, Texas A&M

lnfo Links ............ Randy Hayes, Univ. of Northern lowa

Member Benefit of the Month: Free Webinars

Committee Corner

Board Report......... Riny Ledgerwood, SDSU

Thanks to our 201 1 Exhibitors

Welcome New Members

Check lt Out: Press Releases...Job Postings...RFls/RFPs...Special Deals!...Corporate Webinars


Ethnic Difference In Healthcare Delivery, Benny Mathew Varghese Dec 2011

Ethnic Difference In Healthcare Delivery, Benny Mathew Varghese

Industrial and Management Systems Engineering -- Dissertations and Student Research

Quality in healthcare is a very important aspect; this is obtained when there is proper care provided to the patients without any discrimination. The healthcare system in the US can be improved in the fields of patient’s care, the amount of money spent and proper advice, if proper responsibilities are taken. Quality has been improving over the years, but the median by which there is an increase is too small. The other main factor is access to the healthcare system, which has over the year, has not progressed. Studies in healthcare quality should be conducted on a regular base ...


Economic Analysis Of Continuous Monitoring Of Commercial Truck Tire Pressure Using Tire Pressure Monitoring Systems (Tpms) And Rfid Technologies., Afolabi A. Ogunwemimo Dec 2011

Economic Analysis Of Continuous Monitoring Of Commercial Truck Tire Pressure Using Tire Pressure Monitoring Systems (Tpms) And Rfid Technologies., Afolabi A. Ogunwemimo

Industrial and Management Systems Engineering -- Dissertations and Student Research

The trucking industry is a major contributor to the US economy. By providing the essential services of transportation and distribution needed in today’s dynamic industry, the transportation industry has evolved into an integral player in various supply chains. The trucking industry is the largest transportation provider for other industries and employs 10.1 million workers in the United States (ATA, 2003).

This research is an analysis of the economic impact of maintaining proper air pressure in the tires of commercial trucks. Various studies have been carried out on understanding the relationship between tire pressure and fuel consumption (National Research ...


Electronic Monitoring Of Hand Hygiene Compliance In An Inpatient Hospital Setting, Christopher M. Masek Nov 2011

Electronic Monitoring Of Hand Hygiene Compliance In An Inpatient Hospital Setting, Christopher M. Masek

Industrial and Management Systems Engineering -- Dissertations and Student Research

Proper hand hygiene is known to reduce hospital acquired infections. Currently the most widely accepted method used to measure hand hygiene compliance is through direct observation. This method often provides data that may not accurately represent true hand hygiene compliance due to such factors such as the Hawthorne Effect. Perhaps a better approach is to use counting devices to capture hand hygiene opportunities and activities. This thesis focuses on the measurement of hand hygiene activities of all individuals that either work or visit an inpatient medical ward including healthcare workers, patients and visitors at the patient’s bedside for non-isolation ...


Acuta Enews November 2011, Vol 40, No. 11 Nov 2011

Acuta Enews November 2011, Vol 40, No. 11

ACUTA Newsletters

ln This lssue

From the President: Higher Ed lT services Trending ......Joe Harrington, Boston College

Testing EAS System Nationwide

lnstitutional Excellence Award 2012: Dead time November 11

Nominate Now for 2012-2013 Board of Directors

FREE ACUTA Webinar: DAS Deployment, Options, Contracts, and Regulation

Cellular signal Boosters............ J.G. Harrington, Dow Lohnes, PLLC

Cell Phone Recycling.................Chris lrion, e-Cycle

lnfo Links ........... Randy Hayes, Univ. of Northern lowa

Committee Corner

Recharge at the Kiosk

Board Report.......... Riny Ledgewood, SDSU

Member Benefit of the Month: Member Logos

Thanks to Exhibitors and Sponsors at Fall Seminar

A University in your pocket: Education and Mobile ...


Acuta Enews October 2011, Vol 40, No. 10 Oct 2011

Acuta Enews October 2011, Vol 40, No. 10

ACUTA Newsletters

ln This lssue

Nominate Now for 2012-2013 Board of Directors

Corinne Hoch Named Executive Director

Define Your Expectations to Vendors ......Ron Walczak, Walczak Technology Consultants

Additional Guidance on Taxation of Employer-Provided Cell Phones.......Michael Hepburn, Dow Lohnes

Institutional Excellence Award 2012

From ACUTA Headquarters: Looking Back to the Future.......... Corinne Hoch, Executive Director

Board Report.......... Riny Ledgerwood, SDSU

lnfo Links .,......... .. Randy Hoyes, Univ. of Northern lowa

Committee Corner

Get Your Logos Here!

Documenting the Worth of an lT Degree

Member Benefit of the Month: ACUTA Community

Welcome New Members

Check lt Out: Press Releases...Job Postings...RFls/RFPs...Special Deals ...


Acuta Enews September 2011, Vol 40, No. 9 Sep 2011

Acuta Enews September 2011, Vol 40, No. 9

ACUTA Newsletters

ln This lssue

Hurricane lrene Takes Top Priority for Some

From the President: ACUTA: A Career Development Program Joe Harrington, Boston College

To Attract Top lT Talent, Understand Graduates' Needs

You Don't Have to Be Young to Be "Young"............. Emily Harris, Vassar College

Add Names from Your Campus to Your ACUTA Roster

Freed-Hardeman Students Develop iPhone App

Announcing member Benefit of the Month

lnfo Links ..........Randy Hayes, Univ. of Northern lowa

Retirement

Committee Corner

ACUTA Fall Seminar in Boston

ACUTA Webinar: Transitioning to lPv6 on Your Campus

Board Report..................Riny Ledgerwood, San Diego state univ

Welcome New Members

Check ...


Acuta Enews August 2011, Vol 40, No. 8 Aug 2011

Acuta Enews August 2011, Vol 40, No. 8

ACUTA Newsletters

ln This lssue

From ACUTA Headquarters.......... Corinne Hoch, lnterim Executive Director

Hosted/Cloud Provider Checklist .Gary Audin, Delphi, lnc.

ACUTA Webinar: Transitioning to lPv6 on Your Campus

Connecting in the Digital Age............. . Buck Bayliff, PCR

Campus Tech a Top Factor in College Selection and Perceived Career Success

lnfo Links ........... .. Randy Hayes, Univ. of Northern lowa

View 8 Sessions from the Summer Seminar at Your Desktop

Come to Boston!

Board Report......... Riny Ledgerwood, SDSU

Welcome New Members

Check lt Out: press Releases...Job Postings.,.RFls/RFPs...Special Deals!...Corporate Webinars


Influence Of Process Parameters On Health Outcome, Vijaya K. Musunuru Aug 2011

Influence Of Process Parameters On Health Outcome, Vijaya K. Musunuru

Industrial and Management Systems Engineering -- Dissertations and Student Research

In the recent years, healthcare organizations have realized that quality in providing service is critical for their survival in this competitive world. This increased attention to service quality has forced many health care providers to reevaluate their systems to stay in business. The main purpose of this study is to test the hypothesis “Process Quality predicts the Product quality (patient satisfaction) in the healthcare domain”. The objective of this study was three- fold. The first objective is to analyze historical data both on patient satisfaction and on provider attributes to yield process parameters for a particular area in a hospital ...


Investigation Of Rfid Readability For License Plates In Static And Motion Testing, Srinivasan Venkatesan Jul 2011

Investigation Of Rfid Readability For License Plates In Static And Motion Testing, Srinivasan Venkatesan

Industrial and Management Systems Engineering -- Dissertations and Student Research

The most important function of RFID in vehicle tracking is to store information concerning tagged elements in order to improve the overall performance of movable asset management. There is a need to discover an RFID system for the tracking of vehicles, as existing vehicle tracking systems are undependable. Experiments were performed with SIRIT, SAVI, and RF code RFID systems under differing conditions, attaching the tag to the license plate instead of the windshield. Different spacers were also tested to reduce the effect of metal surfaces on RFID signals.

Preliminary experiments were performed before stationary and motion testing in order to ...


Integration Of A Real Option Of An Environmental Project, Qi Yang Jul 2011

Integration Of A Real Option Of An Environmental Project, Qi Yang

Industrial and Management Systems Engineering -- Dissertations and Student Research

This thesis explores a problem of how to evaluate environmental projects under the Carbon Cap-and-Trade Scheme (CCTS) from the perspective of an individual firm. The focus is the integration of a real option approach for project investment timing and financial carbon option approach for carbon credit management. The real option is for a mid or long term decision on when to invest on the environmental project, and the financial option is for a supplementary decision to hedge short-term residue risks. Two uncertainties (the carbon price and carbon credit demand) are considered, and their changes are represented by a lattice of ...


Acuta Enews July 2011, Vol 40, No. 7 Jul 2011

Acuta Enews July 2011, Vol 40, No. 7

ACUTA Newsletters

ln This lssue

From the President: The "T" in ACUTA....... Joe Harrington, Boston College

Second Dues lnvoices Mailed

The Daily Grind: What's on Your Desk Today?.......... Mona Brennan-Cotes, Univ. of Western Ontario

Calling All Young Professionals Amy Burton, ACUTA Mgr., Membership Mkt. & Corp. Relations

"The Future of Voice Communications": Winter Journal Looking for Articles

Board Report..................Riny Ledgerwood, San Diego State Univ.

Share Your RFIs/RFPs

Good Question on the ACUTA Listserv

lnfo Links ......... Randy Hayes, Univ. of Northern lowa

Disaster Recovery Requires Lots of What-lfs.................... Gary Audin, Delphi, lnc.

ACUTA Fall Seminar in Boston

ACUTA Webinar: Transitioning to ...


A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal., Sarah M. Asio Jul 2011

A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal., Sarah M. Asio

Industrial and Management Systems Engineering -- Dissertations and Student Research

The application of traditional approaches to the design of efficient facilities can be tedious and time consuming when uncertainty and a number of constraints exist. Queuing models and mathematical programming techniques are not able to capture the complex interaction between resources, the environment and space constraints for dynamic stochastic processes. In the following study discrete event simulation is applied to the facility planning process for a grain delivery terminal. The discrete event simulation approach has been applied to studies such as capacity planning and facility layout for a gasoline station and evaluating the resource requirements for a manufacturing facility. To ...


Acuta Enews June 2011, Vol 40, No. 6 Jun 2011

Acuta Enews June 2011, Vol 40, No. 6

ACUTA Newsletters

ln This lssue

From ACUTA Headquarters........ Corinne Hoch, lnterim Executive Director

Voice and Data Networks Weather the Storms at Sewanee.......Jeanne Jansenius, Univ. of the South

Announcing New ACUTA Online forums

CUPA Salary Survey Results

From the ACUTA Community Listserv: VolP lssues

lnfo Links ............ Randy Hayes, Univ. of Northern lowa

Board Report......... Riny Ledgerwad, SDSU

lT's Funny!

Come to Baltimore! Emerging ICT Technologies, Funding ICT Services, and more

View 8 Sessions from the Annual Conference at Your Desktop

Welcome New Members

Check lt Out: Press Releases...Job Postings...RFls/RFPs...Special Deals!...Corporate Webinars


Acuta Enews May 2011, Vol 40, No. 5 May 2011

Acuta Enews May 2011, Vol 40, No. 5

ACUTA Newsletters

ln This lssue

Corinne Hoch Appointed lnterim Executive Director

From the President: Priorities for 2011-2012 ..............Joe Harrington, Boston College

Donations in memory of Jeri Semer

ACUTA: Getting Personal............................ Jeffry Handat, LSU

View 8 Sessions from the Annual Conference at Your Desktop

Why ACUTA Remains Vital

lT's Funny!

lnfo Links ........... .. Randy Hoyes, Univ. of Northern lowa

Annual Dues lnvoices Mailed May 2

The Daily Grind: What's on Your Desk Today? ....., Jeanne Jansenius, Sewanee, University of the South

Board Report........ George Denbow, Univ. of Texas, Austin

Another Great conference, More Terrific Prizes!

Thanks to Exhibiton and Sponsors at Annual Conference ...


Grain Refinement Vs. Crystallographic Texture: Mechanical Anisotropy In A Magnesium Alloy, D. C. Foley, M. Al-Maharbi, K. T. Hartwig, I. Karaman, L. J. Kecskes, S. N. Mathaudhu Apr 2011

Grain Refinement Vs. Crystallographic Texture: Mechanical Anisotropy In A Magnesium Alloy, D. C. Foley, M. Al-Maharbi, K. T. Hartwig, I. Karaman, L. J. Kecskes, S. N. Mathaudhu

US Army Research

A magnesium alloy was subjected to severe plastic deformation via an unconventional equal channel angular extrusion route at decreasing temperatures. This method facilitates incremental grain refinement and enhances formability by activating dynamic recrystallization in the initial steps and suppressing deformation twinning. Compression experiments in three orthogonal directions demonstrated high strength levels in the processed sample, up to 350 MPa in yield and 500 MPa in ultimate strengths. Notable flow stress anisotropy is correlated with the processing texture and microstructure.


Acuta Enews April 2011 Vol. 40, No. 4 Apr 2011

Acuta Enews April 2011 Vol. 40, No. 4

ACUTA Newsletters

ln This lssue

Remembering Jeri Semer

From the President: 2010-2011 in Review............... Matt Arthur, Washington University in St. Louis

ResNet Tips............ Charles Brody, Apogee

lT's Funny!

The Daily Grind: What's on Your Desk Today?......... Riny Ledgerwood, SDSU

Board Report......... George Denbow, Univ. Texas, Austin

When Did We Last Try This?... ..............Gary Audin, Delphi Inc.

View 8 Sessions from the Annual Conference at Your Desktop

ACUTA 2011 Event Calendar

lnfo Links ....... Rondy Hayes, Univ. of Northern lowa

Welcome New Members

Check lt Out: Press Releases...Job Postings...RFls/RFPs...Special Deals!...Corporate Webinars


Acuta Enews March 2011 Vol. 40, No. 3 Mar 2011

Acuta Enews March 2011 Vol. 40, No. 3

ACUTA Newsletters

ln This lssue

Meet the Board for 2011-12

Tech Talk: Take Two Tablets and Catt Me in the Morning.......... Kevin Tanzillo, Dux PR

Free Webinars Coming Soon to ACUTA

Learn More about UC, Voice Trends, the Cloud, and More from Your Desktop

From ACUTA Headquarters: Member Years of Service ,Jeri A. Semer, CAE, Executive Dir

Board Report......... George Denbow, univ. of Texas, Austin

New to ICT or Not, ACUTA Members Are All Busy!........... Young Professionals Subcommittee

lT's Funny!

lnfo Links ........... .. Randy Hayes, Univ' of Northern lowa

ACUTA 2011 Event Calendar

Welcome New Members

Check lt Out: Press Releases...Job ...


Acuta Enews February 2011 Vol. 40, No. 2 Feb 2011

Acuta Enews February 2011 Vol. 40, No. 2

ACUTA Newsletters

ln This lssue

From the President........Matt Arthur, Washington Univ. in St. Louis, ACUTA President

Security Snapshot: Texas A&M

Tech Talk: Maybe They Should Call it Copper Peak................... Kevin Tanzillo, Dux PR

Important lssues on Campus Today

Handling Air Travel Frustrations

lT's Funny.............Cartoon Resource

Lightning Round: New at the Conference

Webinar: The Future of the PBX in a University Environment

Learn More about UC, Voice Trends, the Cloud, and More from Your Desktop

Board Report....... George Denbow, Univ. of Texas, Austin

Thanks to Journal Advertisers for 2010

Thanks to Exhibitors and Sponsors at Winter Seminar

lnfo Links ...


Acuta Enews January 2011 Vol. 40, No. 1 Jan 2011

Acuta Enews January 2011 Vol. 40, No. 1

ACUTA Newsletters

In this issue.....

Board approves slate of nominees

From ACUTA headquaters: rebalancing IT for the future.......... Jeri A. Semer, CAE, Executive Dir.

Nominate now for ACUTA Ruth A. Michalecki Leadership Award

Tech Talk: doing more with less, but in a good way........ Kevin Tanzillo, Dux PR

Washington Update Newsletter

Video Surveillance Technology........ Ron Walczak, RCDD, Walczak Techology Consultants

Forensic Tools: keeping up with the bad guys.......... Gary Audin, Delphi, Inc.

Board Report.............. George Denbow, Univ. of Texas, Austin

Thanks to Event Sponsors for 2010

ACUTA 2011 Event Calender

Info links......... Randy Hayes, Univ. of Northern Iowa

Welcome New Members

Check ...


Protective Efficacy Of Catalytic Bioscavenger, Paraoxonase 1 Against Sarin And Soman Exposure In Guinea Pigs, Manojkumar Valiyaveettil, Yonas Alamneh, Peter Rezk, Lionel Biggemann, Michael W. Perkins, Alfred M. Sciuto, Bhupendra P. Doctor, Madhusoodana P. Nambiar Jan 2011

Protective Efficacy Of Catalytic Bioscavenger, Paraoxonase 1 Against Sarin And Soman Exposure In Guinea Pigs, Manojkumar Valiyaveettil, Yonas Alamneh, Peter Rezk, Lionel Biggemann, Michael W. Perkins, Alfred M. Sciuto, Bhupendra P. Doctor, Madhusoodana P. Nambiar

US Army Research

Human paraoxonase 1 (PON1) has been portrayed as a catalytic bioscavenger which can hydrolyze large amounts of chemical warfare nerve agents (CWNAs) and organophosphate (OP) pesticides compared to the stoichiometric bioscavengers such as butyrylcholinesterase. We evaluated the protective efficacy of purified human and rabbit serum PON1 against nerve agents sarin and soman in guinea pigs. Catalytically active PON1 purified from human and rabbit serum was intravenously injected to guinea pigs, which were 30 min later exposed to 1.2 × LCt50 sarin or soman using a microinstillation inhalation exposure technology. Pre-treatment with 5 units of purified human and rabbit serum ...


Recombinant Paraoxonase 1 Protects Against Sarin And Soman Toxicity Following Microinstillation Inhalation Exposure In Guinea Pigs, Manojkumar Valiyaveettil, Yonas Alamneh, Peter Rezk, Michael W. Perkins, Alfred M. Sciuto, Bhupendra P. Doctor, Madhusoodana P. Nambiar Jan 2011

Recombinant Paraoxonase 1 Protects Against Sarin And Soman Toxicity Following Microinstillation Inhalation Exposure In Guinea Pigs, Manojkumar Valiyaveettil, Yonas Alamneh, Peter Rezk, Michael W. Perkins, Alfred M. Sciuto, Bhupendra P. Doctor, Madhusoodana P. Nambiar

US Army Research

To explore the efficacy of paraoxonase 1 (PON1) as a catalytic bioscavenger, we evaluated human recombinant PON1 (rePON1) expressed in Trichoplusia ni larvae against sarin and soman toxicity using microinstillation inhalation exposure in guinea pigs. Animals were pretreated intravenously with catalytically active rePON1, followed by exposure to 1.2 X LCt50 sarin or soman. Administration of 5 units of rePON1 showed mild increase in the blood activity of the enzyme after 30 min, but protected the animals with a significant increase in survival rate along with minimal signs of nerve agent toxicity. Recombinant PON1 pretreated animals exposed to sarin ...


Thermoreversible And Remendable Glass–Polymer Interface For Fiber-Reinforced Composites, Amy M. Peterson, Robert E. Jensen, Giuseppe R. Palmese Jan 2011

Thermoreversible And Remendable Glass–Polymer Interface For Fiber-Reinforced Composites, Amy M. Peterson, Robert E. Jensen, Giuseppe R. Palmese

US Army Research

Adhesion of the reinforcement to the polymer matrix is essential for load transfer from the polymer matrix to the reinforcement material in fiber-reinforced composites. The reversible Diels–Alder reaction between a furan-functionalized epoxy-amine thermosetting matrix with a maleimide-functionalized glass fiber was used to impart remendability at the polymer–glass interface for potential application in glass fiber-reinforced composites. At room temperature the Diels–Alder adduct is formed spontaneously and above 90 °C the adduct breaks apart to reform the original furan and maleimide moieties. Healing of the interface was investigated with single fiber microdroplet pull-out testing. Following complete failure of this ...


Micro-Cracks Informed Damage Models For Brittle Solids, Xiaodan Ren, Jiun-Shyan Chen, Jie Li, T. R. Slawson, M. J. Roth Jan 2011

Micro-Cracks Informed Damage Models For Brittle Solids, Xiaodan Ren, Jiun-Shyan Chen, Jie Li, T. R. Slawson, M. J. Roth

US Army Research

A class of micro-cracks informed damage models for describing the softening behavior of brittle solids is proposed, in which damage evolution is treated as a consequence of micro-crack propagation. The homogenized stress–strain relation in the cracked microscopic cell defines the degradation tensor, which can be obtained by the equivalence between the averaged strain energy of the microscopic cell and the strain energy density of the homogenized material. This energy equivalence relationship serves as an energy bridging vehicle between the damaged continuum and the cracked microstructure. Several damage evolution equations are obtained by this energy bridging method. The size effect ...


Antimicrobial Decapeptide Ksl-W Attenuates Candida Albicans Virulence By Modulating Its Effects On Toll-Like Receptor, Human Β-Defensin, And Cytokine Expression By Engineered Human Oral Mucosa, A. Semlali, K. P. Leung, S. Curt, M. Rouabhia Jan 2011

Antimicrobial Decapeptide Ksl-W Attenuates Candida Albicans Virulence By Modulating Its Effects On Toll-Like Receptor, Human Β-Defensin, And Cytokine Expression By Engineered Human Oral Mucosa, A. Semlali, K. P. Leung, S. Curt, M. Rouabhia

US Army Research

We investigated the toxicity of synthetic antimicrobial decapeptide KSL-W on normal human gingival epithelial cell cultures, its effect on Candida albicans adhesion and growth, and the activation of epithelial cell innate immunity. Our results indicate that KSL-W had no toxic effect on cell adhesion or growth, suggesting its safe use with human cells. Pre-treating C. albicans with KSL-W attenuated the yeast’s virulence as demonstrated by its reduced adhesion and growth on engineered human oral mucosa epithelium and the subsequent decreased expression of some innate defense molecules by targeted epithelial cells. Indeed, the expression of Toll-like receptors and human β-defensins ...


Digital Holographic Imaging Of Aerosol Particles In Flight, Matthew J. Berg, Gorden Videen Jan 2011

Digital Holographic Imaging Of Aerosol Particles In Flight, Matthew J. Berg, Gorden Videen

US Army Research

This work describes the design and application of an apparatus to image aerosol
particles using digital holography in a flow-through, contact-free manner. Particles in an aerosol stream are illuminated by a triggered, pulsed laser and the pattern produced by the interference of this light with that scattered by the particles is recorded by a digital camera. The recorded pattern constitutes a digital hologram from which an image of the particles is computationally reconstructed using a fast Fourier transform. This imaging is validated using a cluster of ragweed pollen particles. Examples involving mineral-dust aerosols demonstrate the technique’s in situ imaging ...


A New Explanation Of The Extinction Paradox, Matthew J. Berg, C. M. Sorensen, A. Chakrabarti Jan 2011

A New Explanation Of The Extinction Paradox, Matthew J. Berg, C. M. Sorensen, A. Chakrabarti

US Army Research

This work presents a new explanation for the extinction paradox and shows that the canonical explanations are incorrect. This paradox refers to the large size limit of a particle’s extinction cross section. It is called a paradox because the geometrical optics approximation, which should be valid in this limit, predicts a cross section that is half of the true value. The new explanation is achieved by formulating the scattered wave in terms of an integral over the particle’s surface where the seemingly unrelated Ewald–Oseen theorem appears in the formulation. By expressing the cross section in terms of ...


Application Of Hyperspectral Vegetation Indices To Detect Variations In High Leaf Area Index Temperate Shrub Thicket Canopies, Steven T. Brantley, Julie C. Zinnert, Donald R. Young Jan 2011

Application Of Hyperspectral Vegetation Indices To Detect Variations In High Leaf Area Index Temperate Shrub Thicket Canopies, Steven T. Brantley, Julie C. Zinnert, Donald R. Young

US Army Research

Accurate measurement of leaf area index (LAI), an important characteristic of plant canopies directly linked to primary production, is essential for monitoring changes in ecosystem C stocks and other ecosystem level fluxes. Direct measurement of LAI is labor intensive, impractical at large scales and does not capture seasonal or annual variations in canopy biomass. The need to monitor canopy related fluxes across landscapes makes remote sensing an attractive technique for estimating LAI. Many vegetation indices, such as Normalized Difference Vegetation Index (NDVI), tend to saturate at LAI levels >4 although tropical and temperate forested ecosystems often exceed that threshold. Using ...


A Phase Field Model Of Deformation Twinning: Nonlinear Theory And Numerical Simulations, J. D. Clayton, J. Knap Jan 2011

A Phase Field Model Of Deformation Twinning: Nonlinear Theory And Numerical Simulations, J. D. Clayton, J. Knap

US Army Research

A continuum phase field theory and corresponding numerical solution methods are developed to describe deformation twinning in crystalline solids. An order parameter is associated with the magnitude of twinning shear, i.e., the lattice transformation associated with twinning. The general theory addresses the following physics: large deformations, nonlinear anisotropic elastic behavior, and anisotropic phase boundary energy. The theory is applied towards prediction of equilibrium phenomena in the athermal and non-dissipative limit, whereby equilibrium configurations of an externally stressed crystal are obtained via incremental minimization of a free energy functional. Outcomes of such calculations are elastic fields (e.g., displacement, strain ...


Effects Of Gage Length, Loading Rates, And Damage On The Strength Of Ppta Fibers, Jaeyoung Lim, James Q. Zheng, Karl Masters, Weinong W. Chen Jan 2011

Effects Of Gage Length, Loading Rates, And Damage On The Strength Of Ppta Fibers, Jaeyoung Lim, James Q. Zheng, Karl Masters, Weinong W. Chen

US Army Research

Axial tension and transverse compression experiments on single fibers were performed to investigate the mechanical behavior of three high-performance fibers (Kevlar ®, Kevlar ® 129, and Twaron ®) with diameters in the order of 9-12 μm. The single fibers were manufactured from 1998 through 2008. A miniaturized tensile Kolsky bar was used to determine the tensile response of PPTA single fibers at a high strain rate. Gage length and strain rate were found to have minimum effects on the tensile strength of PPTA single fibers. Manufacturing time over a decade was found to have negligible effects on the tensile strength of the fibers ...