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Approximations With Improving Error Bounds For Makespan Minimization In Batch Manufacturing, Whitney Samuel Weyerman Mar 2008

Approximations With Improving Error Bounds For Makespan Minimization In Batch Manufacturing, Whitney Samuel Weyerman

Theses and Dissertations

Multipurpose batch manufacturing systems allow a suite of job types to be processed with a fixed set of machines. These types of systems are commonly found in chemical processing, as well as in computer systems and the service industry. In this thesis we consider the problem of sequencing jobs entering the manufacturing system in order to minimize makespan, or total time to complete processing of the jobs. We formulate this problem as a dynamic programming problem and illustrate the computational difficulty of solving this problem. We give a method for simulation of the system by representing each machine in the …

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Similar But Different: The Complexities Of Students' Mathematical Identities, Diane Skillicorn Hill Mar 2008

Similar But Different: The Complexities Of Students' Mathematical Identities, Diane Skillicorn Hill

Theses and Dissertations

We, as a culture, tend to lump students into broad categories to describe their relationships with mathematics, such as ‘good at math’ or ‘hates math.’ This study focuses on five students each of whom could be considered ‘good at math,’ and shows how the beliefs that make up their mathematical identities are actually significantly different. The study examined eight beliefs that affect a student's motivation to do mathematics: confidence, anxiety, enjoyment of mathematics, skill level, usefulness of mathematics, what mathematics is, what it means to be good at mathematics, and how one learns mathematics. These five students' identities, which seemed …

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Evaluation Of The Applicability Of The Interactive Highway Safety Design Model To Safety Audit Of Two-Lane Rural Highways, Kaitlin Chuo Mar 2008

Evaluation Of The Applicability Of The Interactive Highway Safety Design Model To Safety Audit Of Two-Lane Rural Highways, Kaitlin Chuo

Theses and Dissertations

The Interactive Highway Safety Design Model (IHSDM) is a suite of software developed by the Federal Highway Administration (FHWA) for monitoring and analyzing two-lane rural highways in the United States. As IHSDM is a fairly "young" program a limited amount of research has been conducted to evaluate its practicability and reliability. To determine if IHSDM can be adopted into the engineering decision making process in Utah, a study was conducted under the supervision of the Utah Department of Transportation (UDOT) to evaluate its applicability to audit safety of two-lane rural highways in Utah. IHSDM consists of six modules: Policy Review …

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Error Sensor Strategies For Active Noise Control And Active Acoustic Equalization In A Free Field, Ryan T. Chester Mar 2008

Error Sensor Strategies For Active Noise Control And Active Acoustic Equalization In A Free Field, Ryan T. Chester

Theses and Dissertations

Several measurements may be used as error signals to determine how to appropriately control a sound field. These include pressure, particle velocity, energy density and intensity. In this thesis, numerical models are used to show which signals perform best in is free-field active noise control (ANC) using error sensors located in the near field of the sound sources. The second is equalization in a free field and a semi-free field. Minimized energy density total power output (MEDToPO) plots are developed; these indicate the maximum achievable attenuation for a chosen error sensor as a function of location. A global listening area …

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How Eighth-Grade Students Estimate With Fractions, Audrey Linford Hanks Mar 2008

How Eighth-Grade Students Estimate With Fractions, Audrey Linford Hanks

Theses and Dissertations

This study looked at what components are in student solutions to computational estimation problems involving fractions. Past computational estimation research has focused on strategies used for estimating with whole numbers and decimals while neglecting those used for fractions. An extensive literature review revealed one study specifically directed toward estimating with fractions (Hanson & Hogan, 2000) that researched adult estimation strategies and not children's strategies. Given the lack of research on estimation strategies that children use to estimate with fractions, this study used qualitative research methods to find which estimation components were in 10 eighth-grade students' solutions to estimation problems involving …

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Extending Web Application Development To The User-Editable Space, Brian S. Goodrich Mar 2008

Extending Web Application Development To The User-Editable Space, Brian S. Goodrich

Theses and Dissertations

The growth of the web increased dramatically when users were provided with applications that let them use just their browser to post and edit content on the World Wide Web. Offering users the ability to use their browser to create their own web applications, instead of just posting text and images, would cause another Internet evolution. This thesis describes the EXPPO system (Extensible Page Productions and Operations), a web application development environment for both end-users and technical-users. EXPPO leverages the end-user's previous experience with internet browsers by using a page based development experience or a Page Oriented Architecture. Because applications …

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Improving Performance Of The Filtered-X Least Mean Square Algorithm For Active Control Of Noise Contatining Multiple Quasi-Stationary Tones, Stephan P. Lovstedt Mar 2008

Improving Performance Of The Filtered-X Least Mean Square Algorithm For Active Control Of Noise Contatining Multiple Quasi-Stationary Tones, Stephan P. Lovstedt

Theses and Dissertations

The Filtered-X Least-Mean-Square (FXLMS) algorithm is widely used in active noise control due to its robustness, simplicity, and ability to be implemented in real time. In a feedforward implementation of the FXLMS algorithm, a reference signal that is highly correlated with the noise to be controlled is filtered with an estimate of the transfer function of the secondary path. The convergence characteristics of the FXLMS algorithm have been well studied. A convergence parameter is used to optimize the convergence of the algorithm. However, the optimal value for the convergence parameter is frequency dependent. Thus for noise containing multiple tones at …

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Cpg: Closed Pseudonymous Groups, Reed S. Abbott Mar 2008

Cpg: Closed Pseudonymous Groups, Reed S. Abbott

Theses and Dissertations

Internet users generally feel their actions are anonymous, but this is often not the case. Users can be tracked and their actions logged for future analysis, which is not the desire of most users. Software and services exist which offer anonymity on the Internet when used correctly. Anonymity on the Internet is useful for many people including whistleblowers, dissidents, law enforcement, and the security conscious, but it can be abused. A user can act maliciously under the guise of anonymity without the fear of retribution. Thus, a level of administrative control over users is desirable, even in an anonymous system. …

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Putting The Web Services Specifications To Rest, Dan R. Olsen Mar 2008

Putting The Web Services Specifications To Rest, Dan R. Olsen

Theses and Dissertations

Web services have become a useful and effective way of sharing information over the World Wide Web. SOAP has become a popular way of providing Web services and has been the focus of the Web Services specifications. The Web Services specifications provide additional capabilities to Web Services such as security and policy exchange. Another popular form of Web services includes light-weight Web or RESTful Web services over HTTP. These light-weight Web services are currently not addressed by the Web Services specifications. In order to provide the same capabilities to RESTful Web services, the Web Services specifications will be used to …

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Skill Evaluation In Women's Volleyball, Lindsay Walker Florence Mar 2008

Skill Evaluation In Women's Volleyball, Lindsay Walker Florence

Theses and Dissertations

The Brigham Young University Women's Volleyball Team recorded and rated all skills (pass, set, attack, etc.) and recorded rally outcomes (point for BYU, rally continues, point for opponent) for the entire 2006 home volleyball season. Only sequences of events occurring on BYU's side of the net were considered. Events followed one of these general patterns: serve-outcome, pass-set-attack-outcome, or block-dig-set-attack-outcome. These sequences of events were assumed to be first-order Markov chains where the quality of each contact depended only explicitly on the quality of the previous contact but not on contacts further removed in the sequence. We represented these sequences in …

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A Bittorrent Proxy, Robert Brent Larsen Mar 2008

A Bittorrent Proxy, Robert Brent Larsen

Theses and Dissertations

BitTorrent is a peer-to-peer protocol useful for distributing large files over the Internet. Many organizations use BitTorrent to distribute their software in order to reduce client download time and reduce the load on their servers. While there is a lot of legitimate content available via BitTorrent, some organizations ban BitTorrent usage due to concerns over copyright infringement and the amount of bandwidth that peers can consume. A BitTorrent proxy will allow organizations to control those risks and allow its members to use the BitTorrent protocol for approved uses. It will allow the organization to control the files that are downloaded …

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Analysis Of The Psychometric Properties Of Two Different Concept-Map Assessment Tasks, Kenneth James Plummer Mar 2008

Analysis Of The Psychometric Properties Of Two Different Concept-Map Assessment Tasks, Kenneth James Plummer

Theses and Dissertations

The ability to make sense of a wide array of stimuli presupposes the human tendency to organize information in a meaningful way. Efforts to assess the degree to which students organize information meaningfully have been hampered by several factors including the idiosyncratic way in which individuals represent their knowledge either with words or visually. Concept maps have been used as tools by researchers and educators alike to assist students in understanding the conceptual interrelationships within a subject domain. One concept-map assessment in particular known as the construct-a-map task has shown great promise in facilitating reliable and valid inferences from student …

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Sub-Symbolic Re-Representation To Facilitate Learning Transfer, Dan A. Ventura Mar 2008

Sub-Symbolic Re-Representation To Facilitate Learning Transfer, Dan A. Ventura

Faculty Publications

We consider the issue of knowledge (re-)representation in the context of learning transfer and present a subsymbolic approach for effecting such transfer. Given a set of data, manifold learning is used to automatically organize the data into one or more representational transformations, which are then learned with a set of neural networks. The result is a set of neural filters that can be applied to new data as re-representation operators. Encouraging preliminary empirical results elucidate the approach and demonstrate its feasibility, suggesting possible implications for the broader field of creativity.

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Capacity Of The Continuous-Space Electromagnetic Channel, Michael A. Jensen, Jon W. Wallace Mar 2008

Capacity Of The Continuous-Space Electromagnetic Channel, Michael A. Jensen, Jon W. Wallace

Faculty Publications

Constructing the capacity bound of a multiple-input multiple-output wireless system is often performed by assuming specified antenna configurations and a propagation environment and determining the signaling strategy which maximizes throughput. This paper extends this approach to further determine the optimal antenna characteristics which maximize the capacity for the propagation scenario, with the resulting capacity bound representing the ultimate maximum achievable value if optimal antenna design and signaling are used. In this approach, the spatially-continuous transmit currents and receive fields are represented using eigenfunctions of appropriate operators. It is shown that, except under certain conditions where array supergain solutions emerge, the …

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Experimental Analysis Of A Wideband Adaptive-Mimo Antenna, Michael A. Jensen Mar 2008

Experimental Analysis Of A Wideband Adaptive-Mimo Antenna, Michael A. Jensen

Faculty Publications

An experimental measurement campaign to investigate the wideband performance of an adaptive multiple-input multiple-output (AdaM) antenna consisting of two active and six parasitic antenna elements. The measurements are conducted over a 30 MHz bandwidth at a center frequency of 2.55 GHz and in a variety of locations in an indoor environment. The system uses a traditional two-element array at the transmitter and either a two-element traditional array or the AdaM antenna at the receiver. The results show that compared to the traditional array, the AdaM receive antenna can achieve the same throughput with an average power reduction of 2.7 dB …

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Clouds Search For Variability In Brown Dwarf Atmospheres: Infrared Spectroscopic Time Series Of L/T Transition Brown Dwarfs, D. Stephens, B. Goldman, M. C. Cushing, M. S. Marley, E. Artigau, K. S. Baliyan, V. J. S. Bejar, J. A. Caballero, N. Chanover, M. Connelley, R. Doyon, T. Forveille, S. Ganesh, C. R. Gelino, H. B. Hammel, J. Holtzman, S. Joshi, U. C. Joshi, S. K. Leggett, M. C. Liu Feb 2008

Clouds Search For Variability In Brown Dwarf Atmospheres: Infrared Spectroscopic Time Series Of L/T Transition Brown Dwarfs, D. Stephens, B. Goldman, M. C. Cushing, M. S. Marley, E. Artigau, K. S. Baliyan, V. J. S. Bejar, J. A. Caballero, N. Chanover, M. Connelley, R. Doyon, T. Forveille, S. Ganesh, C. R. Gelino, H. B. Hammel, J. Holtzman, S. Joshi, U. C. Joshi, S. K. Leggett, M. C. Liu

Faculty Publications

L-type ultra-cool dwarfs and brown dwarfs have cloudy atmospheres that could host weather-like phenomena. The detection of photometric or spectral variability would provide insight into unresolved atmospheric heterogeneities, such as holes in a global cloud deck. Indeed, a number of ultra-cool dwarfs have been reported to vary. Additional time-resolved spectral observations of brown dwarfs offer the opportunity for further constraining and characterising atmospheric variability. Aims. It has been proposed that growth of heterogeneities in the global cloud deck may account for the L- to T-type transition when brown dwarf photospheres evolve from cloudy to clear conditions. Such a mechanism is …

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Fundamental Components For Lamina Emergent Mechanisms, Joseph O. Jacobsen Feb 2008

Fundamental Components For Lamina Emergent Mechanisms, Joseph O. Jacobsen

Theses and Dissertations

This thesis introduces lamina emergent mechanisms (LEMs) and presents components that can be used as building blocks to create LEMs capable of more complex motion. As the name suggests, lamina emergent mechanisms are fabricated out of planar materials (the lamina) but their motion is out of that plane (emergent). Lamina emergent mechanisms can provide benefits that include reduced manufacturing costs and minimal volume when in the planar state. The compact initial state of LEMs is beneficial in reducing shipping costs, especially in volume critical applications. LEMs also exhibit the potential benefits of compliant mechanisms, namely increased precision, reduced weight, reduced …

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Observations Of Piezoresistivity For Polysilicon In Bending That Are Unexplained By Linear Models, Tyler L. Waterfall, Gary K. Johns, Robert K. Messenger, Brian D. Jensen, Timothy W. Mclain, Larry L. Howell Feb 2008

Observations Of Piezoresistivity For Polysilicon In Bending That Are Unexplained By Linear Models, Tyler L. Waterfall, Gary K. Johns, Robert K. Messenger, Brian D. Jensen, Timothy W. Mclain, Larry L. Howell

Faculty Publications

Compliant piezoresistive MEMS sensors exhibit great promise for improved on-chip sensing. As compliant sensors may experience complex loads, their design and implementation require a greater understanding of the piezoresistive effect of polysilicon in bending and combined loads. This paper presents experimental results showing the piezoresistive effect for these complex loads. Several n-type polysilicon test structures, fabricated in MUMPs and SUMMiT processes, were tested. Results show that, while tensile stresses cause a linear decrease in resistance, bending stresses induce a nonlinear rise in resistance, contrary to the effect predicted by linear models. In addition, tensile, compressive, and bending loads combine in …

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A Conceptual Model Of Groundwater Flow In Spring Valley, Nv, And Snake Valley, Nv-Ut, Jeremy Micheal Gillespie Feb 2008

A Conceptual Model Of Groundwater Flow In Spring Valley, Nv, And Snake Valley, Nv-Ut, Jeremy Micheal Gillespie

Theses and Dissertations

A geochemical study of major springs and wells in Spring Valley, Nevada, and Snake Valley, Utah-Nevada was initiated in response to the Clark, Lincoln and White Pine Counties Groundwater Development Project proposed by the South Nevada Water Authority (SNWA). Water budget estimates suggest that interbasin flow accounts for a significant portion (~25%) of the water budgets in Spring and Snake Valleys. Although interbasin flow is possible in some areas, alternative plausible explanations place significant uncertainty on water budget allocations. To examine the plausibility of local and interbasin flow paths the groundwater flow in Spring and Snake Valleys was evaluated using …

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Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy Feb 2008

Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy

Faculty Publications

Relaxation of highly vibrationally excited pyrimidine (C4N2H4) by collisions with carbon dioxide has been investigated using diode laser transient absorption spectroscopy. Vibrationally hot pyrimidine (E'=40,635 cm^-1) was prepared by 248-nm excimer laser excitation, followed by rapid radiationless relaxation to the ground electronic state. The nascent rotational population distribution (J=58–80) of the 0000 ground state of CO2 resulting from collisions with hot pyrimidine was probed at short times following the excimer laser pulse. Doppler spectroscopy was used to measure the CO2 recoil velocity distribution for J=58–80 of the 0000 state. Rate constants and probabilities for collisions populating these CO2 rotational states …

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Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu Feb 2008

Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu

Faculty Publications

Exposure to ozone, which is a major component of air pollution, induces a form of asthma that occurs in the absence of adaptive immunity. Although ozone-induced asthma is characterized by airway neutrophilia, and not eosinophilia, it is nevertheless associated with airway hyperreactivity (AHR), which is a cardinal feature of asthma. Because AHR induced by allergens requires the presence of natural killer T (NKT) cells, we asked whether ozone-induced AHR had similar requirements. We found that repeated exposure of wild-type (WT) mice to ozone induced severe AHR associated with an increase in airway NKT cells, neutrophils, and macrophages. Surprisingly, NKT cell-deficient …

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The Planting Of New Bilten, Duane H. Freitag, Robert A. Elmer Feb 2008

The Planting Of New Bilten, Duane H. Freitag, Robert A. Elmer

Swiss American Historical Society Review

Almost forgotten now, the farming region of New Bilten in Wisconsin's Green County was once a pivotal part of the Swiss immigrant community there and deeply intertwined in the founding of the state's renowned cheese-making industry. The region is centered in a valley south of New Glarus once known as the Biltental (Bilten valley), where more than a dozen families from the Canton Glarus village of the same name settled as a group in July of 1847.

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Full Issue Feb 2008

Full Issue

Swiss American Historical Society Review

No abstract provided.

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Open Educational Resources: Enabling Universal Education, David Wiley, Tom Caswell, Shelley Henson, Marion Jensen Feb 2008

Open Educational Resources: Enabling Universal Education, David Wiley, Tom Caswell, Shelley Henson, Marion Jensen

Faculty Publications

The role of distance education is shifting. Traditionally distance education was limited in the number of people served because of production, reproduction, and distribution costs. Today, while it still costs the university time and money to produce a course, technology has made it such that reproduction costs are almost non-existent. This shift has significant implications, and allows distance educators to play an important role in the fulfillment of the promise of the right to universal education. At little or no cost, universities can make their content available to millions. This content has the potential to substantially improve the quality of …

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Stokes Antenna Temperatures, David G. Long, Jeffrey R. Piepmeier, Eni G. Njoku Feb 2008

Stokes Antenna Temperatures, David G. Long, Jeffrey R. Piepmeier, Eni G. Njoku

Faculty Publications

The growing importance of polarimetric radiometers has led to the need for a detailed theory for Stokes antenna temperatures. In this paper, we provide a full Stokes vector formulation of an antenna temperature that accounts for the entire antenna pattern, which includes polarization mixing in the main-beam and sidelobe effects. To derive the Stokes antenna temperatures, we follow the conventional methods in the Earth remote sensing literature while relying on a coherency algebra approach from radio astronomy. Connections and parallels to the conventional approaches are noted along the way. We also introduce generalizations of beam efficiency and cross polarization for …

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Expanded Mathematical Treatment For "Spectral Bias In Adaptive Beamforming With Narrowband Interference'', Brian D. Jeffs, Karl F. Warnick Jan 2008

Expanded Mathematical Treatment For "Spectral Bias In Adaptive Beamforming With Narrowband Interference'', Brian D. Jeffs, Karl F. Warnick

Faculty Publications

This technical note presents extended versions of some mathematical derivations found in the paper Spectral Bias in Adaptive Beamforming with Narrowband Interference which is under review for publication in IEEE Signal Processing Letters. Though the SP Letters paper is self contained and complete, this note provides intermediate steps for some of the equation derivations to assist the interested readers who would like to re-create the results.

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Simulation And Visualization Of Environments With Multidimensional Time, Luther A. Tychonievich Jan 2008

Simulation And Visualization Of Environments With Multidimensional Time, Luther A. Tychonievich

Theses and Dissertations

This work introduces the notion of computational hypertime, or the simulation and visualization of hypothetical environments possessing multidimensional time. An overview of hypertime is provided,including an intuitive visualization paradigm and a discussion of the failure of common simulation techniques when extended to include multidimensional time. A condition for differential equations describing hypertime motion to be amenable to standard time-iterative simulation techniques is provided,but is not satisfied by any known model of physics. An alternate simulation algorithm involving iterative refinement of entire equations of motion is presented,with an example implementation to solve elastic collisions in hypertime. An artificial intelligence algorithm for …

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Using Interactive Diagrams To Teach Graduate Students About Statistical Power, Eric D. Hunter Jan 2008

Using Interactive Diagrams To Teach Graduate Students About Statistical Power, Eric D. Hunter

Theses and Dissertations

This report describes the design, development, implementation, and evaluation of a web-based tutorial designed to teach graduate students about the statistical concept of power. It contains a literature review of techniques used to teach statistics, similar computer-based programs for representing the concept of power, and instructional theories that pertain to web-based tutorials. It describes the process of designing and developing this tutorial in detail. The results section contains a description of the product implementation with three different groups and discusses the qualitative and quantitative findings from each of these implementations. Finally, there is a discussion of the tutorial's strengths and …

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Wireless Authentication Using Remote Passwords, Andrew S. Harding Jan 2008

Wireless Authentication Using Remote Passwords, Andrew S. Harding

Theses and Dissertations

Current authentication methods for wireless networks are difficult to maintain. They often rely on globally shared secrets or heavyweight public-key infrastructure. Wireless Authentication using Remote Passwords (WARP) mitigates authentication woes by providing usable mechanisms for both administrators and end-users. Administrators grant access by simply adding users' personal messaging identifiers (e.g., email addresses, IM handles, cell phone numbers) to an access control list. There is no need to store passwords or other account information. Users simply prove ownership of their authorized identifier to obtain wireless access.

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Some Puzzles From The Joseph Smith Papyri, John Gee Jan 2008

Some Puzzles From The Joseph Smith Papyri, John Gee

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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