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Effects Of Phase And Amplitude Errors On Qam Systems With Error-Control Coding And Soft Decision Decoding, Jason Ellis Aug 2009

Effects Of Phase And Amplitude Errors On Qam Systems With Error-Control Coding And Soft Decision Decoding, Jason Ellis

All Theses

Demodulation of M-ary quadrature amplitude modulation (M-QAM) requires the receiver to estimate the phase and amplitude of the received signal. The demodulator performance is sensitive to errors in these estimates, and the sensitivity increases as M increases. We examine the effects of phase and amplitude errors on the performance of QAM communication systems with error-control coding and soft-decision decoding. A mathematical analysis of these effects is presented for two soft-decision decoding metrics. Performance comparisons are given for 16-QAM and 64-QAM for two error-control coding techniques and two soft-decision decoding metrics.

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Characterization And Enhancement Of Sensing Properties Of Piezoelectric Materials With Applications To Vibration Suppression, Siddharth Aphale Aug 2009

Characterization And Enhancement Of Sensing Properties Of Piezoelectric Materials With Applications To Vibration Suppression, Siddharth Aphale

All Theses

This thesis undertakes the study of piezoelectric properties of polymer-based fabric and film sensors. An enhancement in piezoelectric properties of such sensors, as noted through earlier work, is observed with increasing weight ratios of nanomaterials dispersed in the polymer matrix. A comprehensive mathematical model using cantilever beams is developed to analyze this enhancement both qualitatively and quantitatively. An experimental setup is also developed to implement the proposed real time signal processing necessary to collect required data towards the characterization. In order to distinguish piezoelectric materials from other materials, study of the frequency response of developed fabric sensors to periodic chirp …

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Analysis Of The Neutral Wind Profiles From The Hex Ii Experiment, Tyler Scott Aug 2009

Analysis Of The Neutral Wind Profiles From The Hex Ii Experiment, Tyler Scott

All Theses

The HEX II sounding rocket experiment was carried out on February 14, 2007, during active geomagnetic conditions. Three rockets released trimethyl aluminum (TMA) chemical tracer trails to measure the neutral winds. Three neutral wind profiles obtained from the upleg trails are presented. The profiles are characterized by a strong wind peak around 113 km altitude in the northwestward direction. Below the peak, the winds exhibit strong shear and a smaller wind peak at around 103 km in the southeastward direction. The wind magnitudes are too strong to be attributed to tidal forcing. Above 120 km the winds are consistently to …

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Hierarchical Bayesian Cortical Models: Analysis And Acceleration On Multicore Architectures, Pavan Yalamanchili Aug 2009

Hierarchical Bayesian Cortical Models: Analysis And Acceleration On Multicore Architectures, Pavan Yalamanchili

All Theses

There is a significant interest in the research community to develop large scale,
high performance implementations of neuromorphic models. These have the potential to
provide significantly stronger information processing capabilities than current computing
algorithms. This thesis examines the parallelization of two recent biologically inspired
hierarchical Bayesian cortical models onto recent multicore architectures. These models
have been developed recently based on new insights from neuroscience and have several
advantages over traditional neural networks. In particular, they need far fewer network
nodes to simulate a large scale cortical model than traditional neural networks, making
them computationally more efficient. This is the first …

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Child Cognitive Development As Examined Using The Family Stress Model, Aimee Hanvey Aug 2009

Child Cognitive Development As Examined Using The Family Stress Model, Aimee Hanvey

All Theses

This study used the Family Stress Model to investigate the relationship between economic distress and child cognitive development. A number of family and community processes have been theorized to mediate the relationship between income and child cognitive functioning. Warm parenting, parental stress, and punitive parenting practices were examined as possible mediators in a sample of 12,440 kindergarten children from the Early Childhood Longitudinal Study - Kindergarten (ECLS-K). Cognitive development was evaluated by reading and mathematical standardized tests, and economic distress was measured using the United States Department of Agriculture (USDA) Food Insecurity Scale. The results of this study found support …

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Single Command Rendering With Sun Grid Engine, William Robinson Aug 2009

Single Command Rendering With Sun Grid Engine, William Robinson

All Theses

According to the Autodesk website, Autodesk Maya software is a powerful, integrated 3D modeling, animation, visual effects, and rendering solution. While this statement is true in every sense, one quality that this software and its competitors lack is in the area of resource management. Though not as critical to the other tasks in the production line, resource management is a crucial component of successful rendering. Until recently, Digital Production Arts students have been left to their own means to manage the rendering process; however, with the use of Sun Grid Engine, rendering tasks can be simplified to a single-command process, …

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Portfolio Selection Problem Under Uncertainty And Risk, Dimitri Nowak Aug 2009

Portfolio Selection Problem Under Uncertainty And Risk, Dimitri Nowak

All Theses

The purpose of this research is the investigation of a portfolio problem in an uncertain environment. Given possible investments with random performance depending on uncertain environmental settings the objective is to establish a methodology for construction of a portfolio which is non-dominated with respect to second order stochastic dominance and whose return distribution is preferable for a least risk decision maker.

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Increasing Student Motivation To Become A Successful Industrial Engineer, Danielle Lanigan Aug 2009

Increasing Student Motivation To Become A Successful Industrial Engineer, Danielle Lanigan

All Theses

This paper explores the use of the VIE theory of Motivation in the field of Industrial Engineering Education. This work focuses on two different populations of students, college students who have chosen Industrial Engineering as a major and middle school students with a predisposition toward engineering. To start, we used a mixed methods sequential explanatory study to learn more about Clemson University department of Industrial Engineering students. Quantitatively, the study found that differences exist among different subsets of Industrial Engineering students. Female students have a higher motivation than male students do, and students with university sponsored project experience have a …

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Deploying And Maintaining A Campus Grid At Clemson University, Dru Sepulveda Aug 2009

Deploying And Maintaining A Campus Grid At Clemson University, Dru Sepulveda

All Theses

Many institutions have all the tools needed to create a local grid that aggregates commodity compute resources into an accessible grid service, while simultaneously maintaining user satisfaction and system security. In this thesis, the author presents a three-tiered strategy used at Clemson University to deploy and maintain a grid infrastructure by making resources available to both local and federated remote users for scientific research. Using this approach virtually no compute cycles are wasted. Usage trends and power consumption statistics collected from the Clemson campus grid are used as a reference for best-practices. The loosely-coupled components that comprise the campus grid …

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Optimization Models For Designing Spatially Compact Ecological Reserve Systems, Lakmali Weerasena Aug 2009

Optimization Models For Designing Spatially Compact Ecological Reserve Systems, Lakmali Weerasena

All Theses

Over the past decades, a number of mathematical models and solution techniques have been developed to preserve reserve sites for species and their natural habitats. Two optimization models for designing spatially compact ecological reserve systems are addressed here as zero-one integer programming problems. These formulations have a bicriteria objective function that is a combination of both boundary length and distance. The two formulations cluster the sites into a relatively small number of compact groups while preserving a required number of sites that contain a certain species using a given amount of resources. Two general types of approaches have been developed …

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Revealing The Structure Of A Pre-Transitional Disk: The Case Of The Herbig F Star Sao 206462 (Hd 135344b), C A. Grady, G Schneider, M L. Sitko, G M. Williger, K Hamaguchi, Sean D. Brittain, K Ablordeppey, D Apai, L Beerman, W J. Carpenter Jul 2009

Revealing The Structure Of A Pre-Transitional Disk: The Case Of The Herbig F Star Sao 206462 (Hd 135344b), C A. Grady, G Schneider, M L. Sitko, G M. Williger, K Hamaguchi, Sean D. Brittain, K Ablordeppey, D Apai, L Beerman, W J. Carpenter

Publications

SAO 206462 (HD 135344B) has previously been identified as a Herbig F star with a circumstellar disk with a dip in its infrared excess near 10 mum. In combination with a low accretion rate estimated from Br gamma, it may represent a gapped, but otherwise primordial or "pre-transitional" disk. We test this hypothesis with Hubble Space Telescope coronagraphic imagery, FUV spectroscopy and imagery and archival X-ray data, and spectral energy distribution (SED) modeling constrained by the observed system inclination, disk outer radius, and outer disk radial surface brightness (SB) profile using the Whitney Monte Carlo Radiative Transfer Code. The essentially …

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New Designs For Participatory Research: Modified Photoethnography And The Personal Resource Systems Management (Prsm) Model, Cindy Beacham, Barbara Mcfall Jul 2009

New Designs For Participatory Research: Modified Photoethnography And The Personal Resource Systems Management (Prsm) Model, Cindy Beacham, Barbara Mcfall

Journal of Youth Development

Learning environments significantly influence student behaviors, academic success, school attendance and participation, all of which are problematic today. Less than half of high school students surveyed in 2005 would select the same high school again if given the opportunity, and only 38% agreed that the support they get at school encourages them to learn more. Pursuing increased educational effectiveness, this paper discusses a study that gathered and evaluated middle and high school students’ concepts of ideal student-centered learning environments in selected classrooms. This multi-method, participatory approach put cameras in student hands and ask them to photograph elements desired in their …

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Enhancing Research And Practice In Early Childhood Through Formative And Design Experiments, Barbara A. Bradley, David Reinking Jun 2009

Enhancing Research And Practice In Early Childhood Through Formative And Design Experiments, Barbara A. Bradley, David Reinking

Publications

This article describes formative and design experiments and how they can advance research and instructional practices in early childhood education. We argue that this relatively new approach to education research closes the gap between research and practice, and it addresses limitations that have been identified in early childhood research. We provide examples of this approach's potential benefits, trace its origins, present its defining characteristics, illustrate a representative framework for conducting a formative experiment using an example from our own work and we argue that formative and design experiments introduce useful new metaphors into early childhood research.

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Options For Anderson County School Districts, 2009 June, Holley Hewitt Ulbrich, Ellen Weeks Saltzman, Catherine E. Watt Jun 2009

Options For Anderson County School Districts, 2009 June, Holley Hewitt Ulbrich, Ellen Weeks Saltzman, Catherine E. Watt

Publications

No abstract provided.

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The First Two Transient Supersoft X-Ray Sources In M31 Globular Clusters And The Connection To Classical Novae, M. Henze, W. Pietsch, F. Haberl, G. Sala, R. Quimby, M. Hernanz, M. Della Valle, P. Milne, G. G. Williams, V Burwitz, J Greiner, H Stiele, Dieter H. Hartmann, A.K.H. Dong, K Hornoch Jun 2009

The First Two Transient Supersoft X-Ray Sources In M31 Globular Clusters And The Connection To Classical Novae, M. Henze, W. Pietsch, F. Haberl, G. Sala, R. Quimby, M. Hernanz, M. Della Valle, P. Milne, G. G. Williams, V Burwitz, J Greiner, H Stiele, Dieter H. Hartmann, A.K.H. Dong, K Hornoch

Publications

Context. Classical novae (CNe) have been found to represent the major class of supersoft X-ray sources (SSSs) in our neighbour galaxy M 31. Aims. We determine the properties and evolution of the two first SSSs ever discovered in the M 31 globular cluster (GC) system. Methods. We have used XMM-Newton, Chandra and Swift observations of the centre region of M 31 to discover both SSSs and to determine their X-ray light curves and spectra. We performed detailed analysis of XMM-Newton EPIC PN spectra of the source in Bol 111 (SS1) using blackbody and NLTE white dwarf (WD) atmosphere models. For …

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The Very Short Supersoft X-Ray State Of The Classical Nova M31n 2007-11a, M. Henze, W. Pietsch, G. Sala, M. Della Valle, M. Hernanz, J. Greiner, V. Burwitz, M. J. Freyberg, F. Haberl, Dieter H. Hartmann, P Milne, G G. Williams May 2009

The Very Short Supersoft X-Ray State Of The Classical Nova M31n 2007-11a, M. Henze, W. Pietsch, G. Sala, M. Della Valle, M. Hernanz, J. Greiner, V. Burwitz, M. J. Freyberg, F. Haberl, Dieter H. Hartmann, P Milne, G G. Williams

Publications

Context. Short supersoft X-ray source (SSS) states (durations ≤100 days) of classical novae (CNe) indicate massive white dwarfs that are candidate progenitors of supernovae type Ia. Aims. We carry out a dedicated optical and X-ray monitoring program of CNe in the bulge of M 31. Methods. We discovered M31N 2007-11a and determined its optical and X-ray light curve. We used the robotic Super-LOTIS tele-scope to obtain the optical data and XMM-Newton and Chandra observations to discover an X-ray counterpart to that nova. Results. Nova M31N 2007-11a is a very fast CN, exhibiting a very short SSS state with an appearance …

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Clemson Commencement Program, May 2009, Clemson University May 2009

Clemson Commencement Program, May 2009, Clemson University

Clemson Commencement Programs

No abstract provided.

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On Elliptic Curves, Modular Forms, And The Distribution Of Primes, Ethan Smith May 2009

On Elliptic Curves, Modular Forms, And The Distribution Of Primes, Ethan Smith

All Dissertations

In this thesis, we present four problems related to elliptic curves, modular forms, the distribution of primes, or some combination of the three. The first chapter surveys the relevant background material necessary for understanding the remainder of the thesis. The four following chapters present our problems of interest and their solutions. In the final chapter, we present our conclusions as well as a few possible directions for future research.
Hurwitz class numbers are known to have connections to many areas of number theory. In particular, they are intimately connected to the theory of binary quadratic forms, the structure of imaginary …

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Trade Effect Of A Single Currency In East Africa, Rodgers Mukwaya May 2009

Trade Effect Of A Single Currency In East Africa, Rodgers Mukwaya

All Dissertations

The purpose of this study was to evaluate the effect of a single currency policy for Kenya, Tanzania and Uganda on the volume, value and direction of trade and the distribution of welfare changes between these countries. A single-commodity (maize), multi-country spatial equilibrium model was used to evaluate the possible trade and welfare effects of the proposed single currency. Simulation results show higher levels of aggregate regional production with increased production in Uganda and decreased production in Kenya and Tanzania. The results also show increased aggregate trade in the region, the value of exports from Uganda to Kenya increased by …

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Investigation Of Photophysical And Photochemical Processes In Conjugated Polymer Nanoparticles By Single Particle And Ensemble Spectroscopy, Craig Szymanski May 2009

Investigation Of Photophysical And Photochemical Processes In Conjugated Polymer Nanoparticles By Single Particle And Ensemble Spectroscopy, Craig Szymanski

All Dissertations

Single molecule imaging has emerged as a powerful tool in a range of applications, but the field is limited by a lack of fluorescent probes with sufficient brightness and photostability for many demanding applications such as tracking of single biomolecules in cells and tissues at video rate with 1 nm spatial resolution. Conjugated polymers hold great promise as a solution to these issues, with a high density of π electrons and variety of chemistries, allowing efficient and tunable absorption of light. This dissertation describes the development and characterization of a novel type of nanoparticle composed of conjugated polymer called CPdots. …

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An Examination Of Confined Aquifer Gradient Behavior Under Pumping Conditions, Stefanie Fountain May 2009

An Examination Of Confined Aquifer Gradient Behavior Under Pumping Conditions, Stefanie Fountain

All Dissertations

Accurate and reliable estimates of groundwater flow and contaminant transport models are dependent on an understanding of the aquifer properties used to create the models. The borehole flowmeter has been used with increasing frequency at a variety of sites to produce high resolution vertical hydraulic conductivity (K(z)) distributions [Boggs et al. 1990; Rehfeldt et al. 1989b; Molz et al. 1989, Boman et al. 1997; Dinwiddie et al. 1999]. In theory, the validity of measurements obtained using borehole flowmeters is contingent on the hydraulic head gradients near the well at each discrete depth resulting from the pumping-induced flow having reached quasi-steady-state. …

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Synthesis Of Ionic Liquid Monomers Using Fluorinated Sulfonyl Imide Anions And The 1,3-Dialkylimidazolium Cation, Thomas Hickman May 2009

Synthesis Of Ionic Liquid Monomers Using Fluorinated Sulfonyl Imide Anions And The 1,3-Dialkylimidazolium Cation, Thomas Hickman

All Dissertations

With their unique material and solvent properties, ionic liquids have seen an amazing, exponential increase in interest. After a brief introduction of select areas of interest for these compounds, this thesis mainly focuses on the development of novel polyfunctional ionic liquids and polymeric ionic liquids.
One of the preferred anions for ionic liquids is the bis((trifluoromethyl)sulfonyl) imide anion, first introduced by our group in 1982. It shows excellent thermal stability and the desired resonance delocalization of a negative charge for ionic liquids. A series of monofunctional, difunctional, and multi-functional bis(perfluoroalkylsufonyl)imides, along with 1,3-dialkylimidazolium cations were prepared by direct methylation of …

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Time Series Analysis: A New Look At Some Old Problems, Ferebee Tunno May 2009

Time Series Analysis: A New Look At Some Old Problems, Ferebee Tunno

All Dissertations

This dissertation gives a comprehensive report of my doctoral research in time series analysis from summer 2006 to spring 2009. It is comprised of two main efforts: interval estimation for an autoregressive parameter and arc length tests for equivalent ARIMA dynamics. Such problems are traditional in statistics, but three new theorems and several simulations are presented here that help elucidate new ways to handle them.

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Adsorption-Induced Changes In Enzyme Bioactivity Correlated With Adsorbed Protein Orientation And Conformation, Kenan Fears May 2009

Adsorption-Induced Changes In Enzyme Bioactivity Correlated With Adsorbed Protein Orientation And Conformation, Kenan Fears

All Dissertations

Systems using immobilized enzymes are attractive for a wide range of industrial and medical applications because they allow for fabrication of stable, reusable substrates with a highly specific functionality. The performance of these systems is greatly influenced by the orientation and conformation of the immobilized enzymes. To investigate these relationships, we have developed and applied methods to quantitatively assess the secondary structure of adsorbed enzyme layers on planar surfaces using circular dichroism (CD) spectropolarimetry and evaluate their bioactivity using colorimetric assays. When combined with knowledge of an enzyme's native structure, these methods provide a means to correlate changes in enzyme …

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Development Of The Integrated Censored Robust-Tolerance Engineering Design Systems Via Improved Response Surface Modeling, Abdul-Baasit Shaibu May 2009

Development Of The Integrated Censored Robust-Tolerance Engineering Design Systems Via Improved Response Surface Modeling, Abdul-Baasit Shaibu

All Dissertations

In this dissertation, we intend to integrate censoring into robust-tolerance engineering using improved dual response surface modeling. This is perhaps the first attempt in the quality control literature. In the literature, response surface models have largely been restricted to second order (or quadratic) models and robust-tolerance designs have been restricted to situations involving complete observations. We intend to show that higher order response surface models can be more powerful in terms of prediction ability, and are therefore more reliable than the preferred quadratic models in the general context of robust design. We will also consider formulating robust and tolerance designs …

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Development Of Basic Meat Science Curriculum Standards For Secondary Agricultural Education: Delphi Model, John Duke May 2009

Development Of Basic Meat Science Curriculum Standards For Secondary Agricultural Education: Delphi Model, John Duke

All Dissertations

ABSTRACT
The purpose of this study was to develop basic meat science topics and standards for secondary agricultural education. A Delphi panel was used to develop the instrument. The Delphi panel was composed of four members from academia and industry and four
from the top ten national meat FFA Career Development Events coaches from 2000 to 2005. Two Delphi rounds were used to develop the survey instrument. The modified Delphi started with an outline of basic meat science topics developed by an expert panel
from 16 university basic meat science syllabi. The Delphi panel added or deleted topics, topics were …

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Foundations Of Design Method Development, Sudhakar Teegavarapu May 2009

Foundations Of Design Method Development, Sudhakar Teegavarapu

All Dissertations

A systematic procedure for developing design methods, tools, and/or processes, referred to as meta-method, is proposed. It is hypothesized that design methods developed without following a systematic procedure are not effective and thus are not widely accepted by industry and academia likewise. The systematic framework provided by the meta-method will ensure 1) faster development of design methods, 2) enable tracking of requirements throughout the development process, 3) facilitate efficient exploration and selection of alternatives, 4) document the development process for future reuse, 5) help in testing and validation of design methods, and 6) bridge gap between multiple disciplines by forming …

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Influencing Pedagogy And Belief: A Case Study In The Professional Development Of Teachers Of Mathematics, Charles Howard May 2009

Influencing Pedagogy And Belief: A Case Study In The Professional Development Of Teachers Of Mathematics, Charles Howard

All Dissertations

This study forms a holistic, rich description of the way a professional development experience transformed teachers of mathematics. This professional development targeted teachers from six underachieving schools in a southern state who trained for a week in inquiry techniques of instruction. The method used to study the impact this experience had upon participants is a case study design in which three of the high school teachers were the subjects of analysis. Additional data were incorporated from project administrators and other teachers and assistants involved with the professional development experience. Data sources include highly structured questionnaires, observations, semi-structured interviews, documents, archival …

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Intersections And Representations Of Graphs, John Light May 2009

Intersections And Representations Of Graphs, John Light

All Dissertations

Given two graphs G and H sharing the same vertex set, the edge-intersection spectrum of G and H is the set of possible
sizes of the intersection of the edge sets of both graphs. For example,
the spectrum of two copies of the cycle C5 is {0, 2, 3, 5}, and the spectrum of two copies of the star K1,r is {1, r}. The intersection spectrum was initially studied for designs by Lindner and Fu and others and was originally extended to graphs by Eric Mendelsohn. Several examples are studied, both when G and H are isomorphic and …

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Development Of An Original Laboratory Prototype For A Field Tritium Detector Containing A Pem Electrolyzer Mounted In Series With A Gas Proportional Counter, Aurelie Soreefan May 2009

Development Of An Original Laboratory Prototype For A Field Tritium Detector Containing A Pem Electrolyzer Mounted In Series With A Gas Proportional Counter, Aurelie Soreefan

All Dissertations

Tritium is naturally present in very small concentrations in the environment, principally in the form HTO. Thermonuclear detonations, leaks from waste tanks at the Department of Energy (DOE) sites and accidental releases from nuclear power plants have introduced significant quantities of tritium into the environment. Even though tritium is the least toxic of the known beta emitters, its presence in the environment, primarily in the aqueous form, poses a radiological threat because of its easy accessibility. Tritium removal from the environment is technologically impractical. Thus tritium contamination is generally contained, decays in place and is monitored to protect the public …

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