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Chladni Figures Revisited Based On Nanomechanics, M. Dorrestijn, A. Bietsch, T. Acikalin, Arvind Raman, M. Hegner, E. Meyer, Ch. Gerber Jan 2007

Chladni Figures Revisited Based On Nanomechanics, M. Dorrestijn, A. Bietsch, T. Acikalin, Arvind Raman, M. Hegner, E. Meyer, Ch. Gerber

Birck and NCN Publications

Chladni patterns based on nanomechanics in the microfluidic environment are presented. In contrast with the macroscopic observations in the gaseous environment, nanoparticles are found to move to the nodes, whereas micron-sized particles move to the antinodes of the vibrating interface. This opens the door to size-based sorting of particles in microfluidic systems, and to highly parallel and controlled assembly of biosensors and nanoelectronic circuits.

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Virtual Classroom Extension For Effective Distance Education, Radu Dondera, Chun Jia, Voicu Popescu, Cristina Nita-Rotaru, Melissa Dark Jan 2007

Virtual Classroom Extension For Effective Distance Education, Radu Dondera, Chun Jia, Voicu Popescu, Cristina Nita-Rotaru, Melissa Dark

Department of Computer Science Technical Reports

No abstract provided.

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Indot Guidance Document For In-Situ Soil Flushing, Linda S. Lee, Xihong Zhai, Jaesun Lee Jan 2007

Indot Guidance Document For In-Situ Soil Flushing, Linda S. Lee, Xihong Zhai, Jaesun Lee

JTRP Technical Reports

Many of the Indiana Department of Transportation (INDOT) sites are contaminated with aromatic hydrocarbons and chlorinated solvents; these contaminants often occur in the form of light non-aqueous phase liquids (LNAPLs) or dense non-aqueous phase liquids (DNAPLs). Considerable effort has recently been focused on developing in-situ technologies for removing or destroying NAPL source zones, and several potentially viable methods have emerged including cosolvent-enhanced source zone removal. Most recently, site-specific remedial designs involving a combination of in-situ methods (often referred to as a treatment train) have been proposed for which data are still sparse. The primary goal of the laboratory experiments is …

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Announcements Jan 2007

Announcements

The Writing Center Journal

No abstract provided.

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Pricing Of Advertisements On The Internet , Subramanian Balachander, Karthik Kannan Jan 2007

Pricing Of Advertisements On The Internet , Subramanian Balachander, Karthik Kannan

Purdue CIBER Working Papers

Online advertisements are increasingly becoming an attractive channel for advertising. Pricing for online ads has evolved over time, and different auction-based policies are employed by website publishers to sell online ads. In this paper, we analyze, under different scenarios, the following three auction-based policies commonly used by the publishers: (i) invite bids for an impression of an ad, display the highest bidder’s ad, and charge the winning advertiser the submitted bid (ii) invite bids for a click of an ad, display the ad of the bidder submitting the highest bid for a click, and charge the winner the bid submitted, …

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Paths To Quality: A Child Care Quality Rating System For Indiana. What Is It's Scientific Basis?, James Elicker Jan 2007

Paths To Quality: A Child Care Quality Rating System For Indiana. What Is It's Scientific Basis?, James Elicker

Center for Families Publications

Paths to QUALITY is Indiana’s new statewide child care quality rating system (QRS), first implemented in 2008. The main components of most state QRS programs are: 1) a set of quality standards that apply to home-based and center-based child care; 2) a process for objectively assessing child care quality and maintaining accountability; 3) a system of training and technical assistance to help child care providers improve quality; 4) incentives to encourage providers to reach higher levels of quality; and 5) public information to inform parents about what the QRS is and how to use it when they make child care …

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Experimental And Computational Studies Of Temperature Gradient Driven Molecular Transport In Gas Flows Through Nano/Micro-Scale Channels, Yen-Lin Han, Alina A. Alexeenko, Marcus Young, Eric Phillip Muntz Jan 2007

Experimental And Computational Studies Of Temperature Gradient Driven Molecular Transport In Gas Flows Through Nano/Micro-Scale Channels, Yen-Lin Han, Alina A. Alexeenko, Marcus Young, Eric Phillip Muntz

School of Aeronautics and Astronautics Faculty Publications

Studies at the University of Southern California have shown that an unconventional solid-state device, the Knudsen Compressor, can be operated as a micro-scale pump or compressor. The critical components of Knudsen Compressors are gas transport membranes, which can be formed from porous materials or densely packed parallel arrays of channels. An applied temperature gradient across a transport membrane creates a thermal creep pumping action. Experimental and computational techniques that have been developed for the investigations will be discussed. Experimental studies of membranes formed from machined aerogels, activated by radiant heating, have been used to investigate thermal creep flows. In computational …

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Natural Focusing Of X Rays From Ferroelectric Lithium Niobate Wafers, S. Durbin, T. Jach, S. Kim, V. Gopalan Jan 2007

Natural Focusing Of X Rays From Ferroelectric Lithium Niobate Wafers, S. Durbin, T. Jach, S. Kim, V. Gopalan

Department of Physics and Astronomy Faculty Publications

The interaction of waves with inhomogeneous media leads to the natural focusing of light, the channelling of waves into stable caustics. We have extended natural focusing to x rays, observing caustics in topographs of ferroelectric lithium niobate. Voltage across domains of reversed polarity induces perturbations to the local crystal planes, producing dramatic variations in the images. Ray tracing shows a "catastrophic" discontinuity, causing bright focal lines. Analysis reveals details of boundary strains and local ferroelectric properties. Controlled focusing could be extended to designed domain patterns to probe microstructural properties, and also to a type of voltage-controlled ferroelectric optics for x …

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Dissipation In Intercluster Plasma, M. Lyutikov Jan 2007

Dissipation In Intercluster Plasma, M. Lyutikov

Department of Physics and Astronomy Faculty Publications

We discuss dissipative processes in strongly gyrotropic, nearly collisionless plasma in clusters of galaxies ( the ICM). First, we point out that Braginskii's theory, which assumes that collisions are more frequent that the system's dynamical timescale, is inapplicable to fast, subviscous ICM motion. Most importantly, the electron contribution to collisional magnetoviscosity dominates over that of ions for short-scale Alfvenic motions with wavelength satisfying l <=(lambda/root beta)(m(e)/m(p))(1/4) similar to 1 kpc( where lambda is the particle's mean free path, beta is the plasma pressure parameter, and and are electron and proton masses). Thus, if a turbulent cascade develops in the m m e p ICM and propagates down to scales <= 1 kpc, it is damped collisionally not on ions, but on electrons. Second, in high-beta plasma of the ICM, small variations of the magnetic field strength, of relative value similar to 1/beta, lead to the development of anisotropic pressure instabilities ( firehose, mirror, and cyclotron). Unstable wave modes may provide additional resonant scattering of particles, effectively keeping the plasma in a state of marginal stability. We show that in this case the dissipation rate of a laminar, subsonic, incompressible flows scales as the inverse of the plasma b parameter. We discuss application to the problem of ICM heating.

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Evoke Communications, Purdue Ect Team Jan 2007

Evoke Communications, Purdue Ect Team

ECT Fact Sheets Archive

Using Evoke Webconferencing technology, users can avoid expensive long distance rates by having participants listen in over the Web - using only their standard Internet connection and browser.

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Akamai Streaming, Purdue Ect Team Jan 2007

Akamai Streaming, Purdue Ect Team

ECT Fact Sheets Archive

Akamai offers world-class streaming media services that enable Internet content providers and enterprises to succeed in today's Web-centric marketplace. They deliver live event Webcasts (complete with video production, encoding, and signal acquisition services), streaming media on demand, 24/7 Webcasts and a variety of streaming application services based upon their EdgeAdvantage.

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Cyonyx - Advanced Performance Pipe, Purdue Ect Team Jan 2007

Cyonyx - Advanced Performance Pipe, Purdue Ect Team

ECT Fact Sheets Archive

A highly corrosion-resistant composite pipe able to withstand impact in high-traffic areas. While some lined steel and metal alloy pipe are capable of withstanding critical fluids and providing necessary impact resistance, the cost, weight, and limited life expectancy are prohibitive. CYONYX pipe is derived from a new technology that imparts extremely high corrosion resistance, impact resistance approaching that of steel, low material and installation costs, and life expectancy exceeding lined steel and metal alloys.

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Sensors For Scaps, Purdue Ect Team Jan 2007

Sensors For Scaps, Purdue Ect Team

ECT Fact Sheets Archive

The Site Characterization and Analysis Penetrometer System (SCAPS) platform consists of a 20-ton truck equipped with vertical hydraulic rams that are used to force a cone penetrometer into the ground at a speed of 2 cm/sec to depths of approximately 50 m in nominally consolidated fine-grained soils when using a 100-m umbilical cable (25 m when using 50-m umbilical cables). The SCAPS program is currently conducting field verification investigations on state-of-the-art penetrometer mounted sensor and sampler systems for the real-time in situ detection of petroleum products, explosive compounds, volatile organic compounds (VOC), solvents, and gamma emitting radionuclides.

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Air Ventilation Protection System For Building Security, Purdue Ect Team Jan 2007

Air Ventilation Protection System For Building Security, Purdue Ect Team

ECT Fact Sheets Archive

The new technology to solve the limitation of conventional Collective protection equipment (CPE) system has been developed as "Combined ESP/ESF/PCO and microfibrous media CPE application". This concept of this new technology is the combination of the both systems; 1) Microfibrous Material Technology, and 2) Photocataytic Oxidation Technology.

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Funnel & Gate System, Purdue Ect Team Jan 2007

Funnel & Gate System, Purdue Ect Team

ECT Fact Sheets Archive

The limited success and high cost of traditional 'active' ground-water-contaminant plume management efforts (i.e., pump-and-treat systems) has stimulated a search for less expensive 'passive' plume interception and in-situ treatment technologies. The 'funnel and gate system,' which uses heterogeneous (surface-mediated) reactions on porous media to degrade dissolved contaminants, is one passive technology under consideration.

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In Situ Remediation Using Horizontal Wells, Purdue Ect Team Jan 2007

In Situ Remediation Using Horizontal Wells, Purdue Ect Team

ECT Fact Sheets Archive

Horizontal well technology has been widely used in petroleum and underground utility installation. Since late 1980's, the technology has been adapted for environmental remediation applications. Two general methods in drilling horizontal wells have been used in remediation, trenched and directionally-drilled. The first method involves the excavation of a relatively large diameter borehole, with simultaneous installation of well materials and backfill. The second method, directional drilling, produces a smaller diameter borehole and well materials are installed following the completion of drilling activities.

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Heat And Mass Transport In Heat Pipe Wick Structures, B. D. Iverson, T. W. Davis, S V. Garimella, M. T. North, S. Kang Jan 2007

Heat And Mass Transport In Heat Pipe Wick Structures, B. D. Iverson, T. W. Davis, S V. Garimella, M. T. North, S. Kang

CTRC Research Publications

Anovel experimental approach is developed for characterizing the performance of heat pipe wick structures. This approach simulates the actual operation of wick structures in a heat pipe. Open, partially submerged, sintered copper wicks of varying pore size are studied under the partially saturated conditions found in normal heat pipe operation. A vertical wick orientation, where the capillary lift is in opposition to gravity, is selected to test the wicks under the most demanding conditions. Mass transport measurements of the working fluid, in addition to the temperature field, are obtained for the porous wicks under the action of a discrete heat …

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Analysis Of Solid-Liquid Phase Change Under Pulsed Heating, S. Krishnan, J. Y. Murthy, S V. Garimella Jan 2007

Analysis Of Solid-Liquid Phase Change Under Pulsed Heating, S. Krishnan, J. Y. Murthy, S V. Garimella

CTRC Research Publications

Solid/liquid phase change occurring in a rectangular container with and without metal foams subjected to periodic pulsed heating is investigated. Natural convection in the melt is considered. Volume-averaged mass and momentum equations are employed, with the Brinkman–Forchheimer extension to Darcy’s law used to model the porous resistance. A local thermal nonequilibrium model, assuming equilibrium melting at the pore scale, is employed for energy transport through the metal foams and the interstitial phase change material (PCM). Separate volumeaveraged energy equations for the foam and the PCM are written and are closed using a heat transfer coefficient. The enthalpy method is employed …

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Prediction Of Effective Thermo-Mechanical Properties Of Particulate Composites, S R. Annapragada, D Sun, S V. Garimella Jan 2007

Prediction Of Effective Thermo-Mechanical Properties Of Particulate Composites, S R. Annapragada, D Sun, S V. Garimella

CTRC Research Publications

A micromechanics-based model is developed to predict the effective thermo-mechanical properties of energetic materials, which are composite materials made from agglomeration of particles of a range of sizes. A random packing algorithm is implemented to construct a representative volume element for the heterogeneous material based on the experimentally determined particle diameter distribution. The effective mechanical properties of the material are then evaluated through finite element modeling, while its thermal properties are deter- mined through a finite volume approach. The model is first carefully validated against results from the literature and is then used to estimate the thermo-mechanical properties of particular …

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Performance Modeling Of An Rf Coaxial Plasma Thruster, William B. Stein, Alina A. Alexeenko, Ivana Hrbud, Evgeniy Bondar Jan 2007

Performance Modeling Of An Rf Coaxial Plasma Thruster, William B. Stein, Alina A. Alexeenko, Ivana Hrbud, Evgeniy Bondar

School of Aeronautics and Astronautics Faculty Publications

The RF plasma thruster has considerable potential to ease the impact of severe constraints on power, mass, volume and lifetime of microsatellite propulsion systems. This concept is classified as an electrothermal propulsion system and exploits RF capacitively coupled discharge (RFCCD) for heating of a propellant. The plasma is characterized as a low-power discharge possessing a low-current density with high uniformity and propagating through low-pressure gas. To assess computationally the thruster’s propulsive capabilities as a function of mass flow rate, electrode separation, RF frequency and power input, a numerical model comprises particle-in-cell/Monte Carlo (PIC/MCC) and Direct Simulation Monte Carlo (DSMC) algorithms. …

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"Khmer Pride": Being And Becoming Khmer-American In An Urban Migrant Education Program, Theresa Ann Mcginnis Jan 2007

"Khmer Pride": Being And Becoming Khmer-American In An Urban Migrant Education Program, Theresa Ann Mcginnis

Journal of Southeast Asian American Education and Advancement

This article focuses on the ways an urban migrant education program becomes a space where middle school Khmer students can explore who they are as Khmer youth living in an urban American context. I discuss how the youth are able to take a transformative, interactional stance to the literacy and sign-making practices within the program. I argue that the Khmer youth's identities are reflected within these literacy and expressive practices. Further, I suggest the experiences of these Khmer middle school children of agricultural workers provide rich examples of how immigrant youth draw on a variety of cultural resources (from urban …

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Review: A Guide To Creating A Student-Staffed Writing Center: Grades 6-12, Catherine Oriani Jan 2007

Review: A Guide To Creating A Student-Staffed Writing Center: Grades 6-12, Catherine Oriani

The Writing Center Journal

No abstract provided.

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Information For The Authors Jan 2007

Information For The Authors

The Writing Center Journal

No abstract provided.

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A Study Of Effective Soil Compaction Control Of Granular Soils, Vincent P. Drnevich, Aaron C. Evans, Adam Buser Prochaska Jan 2007

A Study Of Effective Soil Compaction Control Of Granular Soils, Vincent P. Drnevich, Aaron C. Evans, Adam Buser Prochaska

JTRP Technical Reports

Although it is known that impact compaction tests are not appropriate for granular soils, these tests continue to be widely used. Excessive settlements frequently occur in granular soils where specified field compaction is based on Standard Proctor (ASTM D 698; AASHTO T 99) maximum dry unit weights. A laboratory test program evaluated alternative test methods for granular soil compaction control and showed that a Vibrating Hammer method (similar to British Standard BS 1377:1975, Test 14) has great promise for laboratory compaction of these soils. A One-Point Vibrating Hammer test on an oven-dry soil sample is able to provide the maximum …

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Effective And Robust Coordination Of Traffic Signals On Arterial Streets, Volume 2, Guidelines Of Design, Wei Li, Andrew P. Tarko Jan 2007

Effective And Robust Coordination Of Traffic Signals On Arterial Streets, Volume 2, Guidelines Of Design, Wei Li, Andrew P. Tarko

JTRP Technical Reports

Many transportation agencies use Synchro and SimTraffic software package to optimize signal coordination. In general, this software package effectively reduces the efforts of traffic systems engineers and improves the quality of the designed coordination. Nevertheless, the initial solutions given by the software packages usually require adjustment, at both the design and implementation stages. The major objective of this research, therefore, is to reduce the time and effort needed in solution tuning and thus to improve the effectiveness and the efficiency of using Synchro/SimTraffic in arterial signal coordination design. The research outcome is expected to help traffic systems engineers reach reasonable …

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Information For The Authors Jan 2007

Information For The Authors

The Writing Center Journal

No abstract provided.

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Announcements Jan 2007

Announcements

The Writing Center Journal

No abstract provided.

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The Use Of A Four-Microphone Standing Wave Tube To Estimate The Anisotropic Properties Of Fibrous Noise Control Materials, J Stuart Bolton, Taewook Yoo, Jonathan H. Alexander Dec 2006

The Use Of A Four-Microphone Standing Wave Tube To Estimate The Anisotropic Properties Of Fibrous Noise Control Materials, J Stuart Bolton, Taewook Yoo, Jonathan H. Alexander

Publications of the Ray W. Herrick Laboratories

No abstract provided.

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Social Media Simplified, Karen Christensen Dec 2006

Social Media Simplified, Karen Christensen

Against the Grain

No abstract provided.

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Language In Modern African Drama, Isaiah Ilo Dec 2006

Language In Modern African Drama, Isaiah Ilo

CLCWeb: Comparative Literature and Culture

In his paper "Language in Modern African Drama" Isaiah Ilo proposes alternative criteria for language choice in modern African drama. The two most influential constructs on the language question are Fanon's essentialism that rejects Western languages as instruments of subjugation and Achebe's hybrid approach which entails subversion of the foreign languages by infusing them with African verbal characteristics. The constructs, which emphasise indigenised language and content, stem from the idea that consciousness of the colonial experience should determine language choice and usage in post-colonial African literary creativity. In building a case for a post-indiginist aesthetic, Ilo argues that present reality …

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