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Predicting The Longevity Of Dvdr Media By Periodic Analysis Of Parity, Jitter, And Ecc Performance Parameters, Daniel Patrick Wells Jul 2008

Predicting The Longevity Of Dvdr Media By Periodic Analysis Of Parity, Jitter, And Ecc Performance Parameters, Daniel Patrick Wells

Theses and Dissertations

For the last ten years, DVD-R media have played an important role in the storage of large amounts of digital data throughout the world. During this time it was assumed that the DVD-R was as long-lasting and stable as its predecessor, the CD-R. Several reports have surfaced over the last few years questioning the DVD-R's ability to maintain many of its claims regarding archival quality life spans. These reports have shown a wide range of longevity between the different brands. While some DVD-Rs may last a while, others may result in an early and unexpected failure. Compounding this problem is …

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Simple, Secure, Selective Delegation In Online Identify Systems, Bryant Gordon Cutler Jul 2008

Simple, Secure, Selective Delegation In Online Identify Systems, Bryant Gordon Cutler

Theses and Dissertations

The ability to delegate privileges to others is so important to users of online identity systems that users create ad hoc delegation systems by sharing authentication credentials if no other easy delegation mechanism is available. With the rise of internet-scale relationship-based single sign-on protocols like OpenID, the security risks of password sharing are unacceptable. We therefore propose SimpleAuth, a simple modification to relationship-based authentication protocols that gives users a secure way to selectively delegate subsets of their privileges, making identity systems more flexible and increasing user security. We also present a proof-of-concept implementation of the SimpleAuth pattern using the sSRP …

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Modeling Phase Transitions Of Nanoemulsion For Ultrasonic Gene Delivery, Ghaleb A. Husseini, William G. Pitt, Ram Singh Jul 2008

Modeling Phase Transitions Of Nanoemulsion For Ultrasonic Gene Delivery, Ghaleb A. Husseini, William G. Pitt, Ram Singh

Faculty Publications

A computer model was written that simulates the transformation of a nanoemulsion droplet to a gas bubble by the application of ultrasound. Experimentally such a technique could be used to enhance non-viral gene transfection beyond the boundary of the endothelial lining of the circulatory system, particularly in tumors exhibiting enhanced permeation and retention of nanoparticles.

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Genetic Analysis Of The Role Of Smpb In Establishing The Reading Frame On Tmrna, Talina Christensen Watts Jul 2008

Genetic Analysis Of The Role Of Smpb In Establishing The Reading Frame On Tmrna, Talina Christensen Watts

Theses and Dissertations

Ribosomes translate the genetic information encoded by mRNA into proteins. Defective mRNAs can cause stalling of translating ribosomes. The molecule tmRNA (transfer-messenger RNA) rescues stalled ribosomes in eubacteria. Together with its protein partner SmpB, tmRNA mimics a tRNA by entering the ribosomal A site and linking an alanine residue to the growing polypeptide chain. The ribosome then abandons the defective mRNA template and resumes translation on tmRNA, adding ten more amino acids to the nascent polypeptide. As a result of tmRNA action, stalled ribosomes are released and recycled, the defective mRNA is destroyed, and the aborted protein product is tagged …

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An Ultrahigh Stability, Low-Noise Laser Current Driver With Digital Control, Christopher J. Erickson, Marshall Van Zijll, Greg Doermann, Dallin S. Durfee Jul 2008

An Ultrahigh Stability, Low-Noise Laser Current Driver With Digital Control, Christopher J. Erickson, Marshall Van Zijll, Greg Doermann, Dallin S. Durfee

Faculty Publications

We present a low-noise, high modulation-bandwidth design for a laser current driver with excellent long-term stability. The driver improves upon the commonly used Hall–Libbrecht design. The current driver can be operated remotely by way of a microprocessing unit, which controls the current set point digitally. This allows precise repeatability and improved accuracy and stability. It also allows the driver to be placed near the laser for reduced noise and for lower phase lag when using the modulation input. We present the theory of operation for our driver in detail, and give a thorough characterization of its stability, noise, set-point accuracy …

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Student Teacher Knowledge And Its Impact On Task Design, Tenille Cannon Jul 2008

Student Teacher Knowledge And Its Impact On Task Design, Tenille Cannon

Theses and Dissertations

This study investigated how student teachers used their mathematical knowledge for teaching and pedagogical knowledge to design and modify mathematical tasks. It also examined the relationship between teacher knowledge and the cognitive demands of a task. The study relied heavily on the framework in Hill, Ball, and Shilling (2008), which describes the different domains of knowledge in mathematical knowledge for teaching, and the framework on the cognitive demands of mathematical tasks in Stein, Smith, Henningsen, and Silver (2000). Results of the study indicated that the student teachers used their common content knowledge when they lacked sufficient knowledge in other domains, …

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Using Live Sequence Chart Specifications For Formal Verification, Rahul Kumar Jul 2008

Using Live Sequence Chart Specifications For Formal Verification, Rahul Kumar

Theses and Dissertations

Formal methods play an important part in the development as well as testing stages of software and hardware systems. A significant and often overlooked part of the process is the development of specifications and correctness requirements for the system under test. Traditionally, English has been used as the specification language, which has resulted in verbose and difficult to use specification documents that are usually abandoned during product development. This research focuses on investigating the use of Live Sequence Charts (LSCs), a graphical and intuitive language directly suited for expressing communication behaviors of a system as the specification language for a …

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Complete Tropical Bezout's Theorem And Intersection Theory In The Tropical Projective Plane, Gretchen Rimmasch Jul 2008

Complete Tropical Bezout's Theorem And Intersection Theory In The Tropical Projective Plane, Gretchen Rimmasch

Theses and Dissertations

In this dissertation we prove a version of the tropical Bezout's theorem which is applicable to all tropical projective plane curves. There is a version of tropical Bezout's theorem presented in other works which applies in special cases, but we provide a proof of the theorem for all tropical projective plane curves. We provide several different definitions of intersection multiplicity and show that they all agree. Finally, we will use a tropical resultant to determine the intersection multiplicity of points of intersection at infinite distance. Using these new definitions of intersection multiplicity we prove the complete tropical Bezout's theorem.

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Predicting Sixth Grade Performance On Criterion-Referenced Reading Tests With Third Grade Test Scores, Michael Sean Gallacher Jul 2008

Predicting Sixth Grade Performance On Criterion-Referenced Reading Tests With Third Grade Test Scores, Michael Sean Gallacher

Theses and Dissertations

This study analyzed the correlation between students' third grade reading ability and sixth grade reading ability. The data were collected from an urban school district, and the participants were students whose records contained information from their third grade school year and their sixth grade school year. The Utah English Language Arts Criterion-Referenced Tests (ELA-CRT) administered in third and sixth grade were used to determine reading ability. Additional demographic data, including race, gender, special education identification, free/reduced lunch, and English Language Learner (ELL), was assessed and controlled for in the data analysis and provided important information concerning the overall findings. Analysis …

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Non-Pedophilic Heterosexual Male Response To Affinity 2.0, Charles D. Crosby Jul 2008

Non-Pedophilic Heterosexual Male Response To Affinity 2.0, Charles D. Crosby

Theses and Dissertations

Given that the Affinity 2.0 is a largely untested instrument that purports to measure sexual attraction, it was unknown whether or not the instrument is temporally stable and would provide a characteristic response curve for normal heterosexual male sexual interest. This study examined the Affinity 2.0, a newly standardized viewing time (VT) instrument that purports to measure sexual interest. More specifically, the Affinity 2.0 was examined in regard to its temporal stability and ability to generate a characteristic curve for non-pedophilic, exclusively heterosexual male interests. This examination was carried out by administering the Affinity 2.0 twice on a sample of …

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Ion Permeation Through Membrane Channels: Molecular Dynamics Simulations Studies, Morad Mustafa Jul 2008

Ion Permeation Through Membrane Channels: Molecular Dynamics Simulations Studies, Morad Mustafa

Theses and Dissertations

Molecular dynamics simulation was used to study ion permeation through different membrane proteins embedded in a lipid bilayer (DMPC) with different saline solutions. The potential of mean force (PMF) for ion transport was obtained by umbrella sampling simulations. A revised MacKerell force field for tryptophan residues was studied using gramicidin A (gA) channel as a test model. The revised force field contribution to the Na+ PMF was consonant with the prediction from the experimental results, but in stark contrast to the prediction of the CHARMM force field, version 22, for the tryptophan side-chain. A new grid-based correction map algorithm by …

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Competitive Exclusion Of Cyanobacterial Species In The Great Salt Lake, Hillary Christine Roney Jul 2008

Competitive Exclusion Of Cyanobacterial Species In The Great Salt Lake, Hillary Christine Roney

Theses and Dissertations

Under Gause's principle two species cannot indefinitely occupy the same niche. The north and south arms of Great Salt Lake are separated by a rail causeway, resulting in salinity differences and color variation between the arms. Farmington Bay is also separated from the south arm by a vehicular causeway to Antelope Island. These causeways allow examination of competitive exclusion of cyanobacteria in the hypersaline environment of the Great Salt Lake. Cyanobacterial distributions partially map salinity, with Aphanothece halophytica proliferating in the north arm, and Nodularia spumigena in the south arm. I hypothesized that cyanobacterial species abundant north of the railway …

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Early Dynamics Of Ultracold Neutral Plasmas, Adam W. Denning Jul 2008

Early Dynamics Of Ultracold Neutral Plasmas, Adam W. Denning

Theses and Dissertations

We report new studies on the early-time dynamics of ultracold neutral plasmas. We use fluorescence spectroscopy to probe plasma dynamics on the nanosecond time scale. We determine the rms ion velocity during the initial plasma period. The initial ion acceleration is found as the time derivative of the ion velocity. We compare to a theoretical model. The experimental results agree with the model at low plasma densities. However, the ion acceleration is a factor of ten lower than the model at higher densities. The cause of this discrepancy is currently unknown.

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Adapting Adtrees For Improved Performance On Large Datasets With High Arity Features, Robert D. Van Dam Jul 2008

Adapting Adtrees For Improved Performance On Large Datasets With High Arity Features, Robert D. Van Dam

Theses and Dissertations

The ADtree, a data structure useful for caching sufficient statistics, has been successfully adapted to grow lazily when memory is limited and to update sequentially with an incrementally updated dataset. However, even these modified forms of the ADtree still exhibit inefficiencies in terms of both space usage and query time, particularly on datasets with very high dimensionality and with high arity features. We propose five modifications to the ADtree, each of which can be used to improve size and query time under specific types of datasets and features. These modifications also provide an increased ability to precisely control how an …

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Towards A New Currency Of Economic Criticism, Jason G. Douglas Jul 2008

Towards A New Currency Of Economic Criticism, Jason G. Douglas

Theses and Dissertations

“The Purloined Letter,” Edgar Allan Poe's third and final tale featuring the detective Dupin, has evoked a long history of critical response. Criticism has tended to read the text for its role in the development of detective fiction and as illustrative of various theoretical positions. However, the implications of the “The Purloined Letter,” as a tale of ratiocination, has largely been left unexplored. “The Purloined Letter” explores logical processes of value and exchange, particularly economic exchange, in a manner very similar to what Charles Sanders Peirce will call pragmatism several decades later. Dupin's deductive methods and Peirce's abductive logic express …

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Becoming A Teacher Educator: A Self-Study Of Learning And Discovery As A Mentor Teacher, Julie Anne Castro Jul 2008

Becoming A Teacher Educator: A Self-Study Of Learning And Discovery As A Mentor Teacher, Julie Anne Castro

Theses and Dissertations

The purpose of this study was to examine what I encountered as I moved from the role of a classroom teacher into the role of a mentor teacher of student teachers. As I traveled down the path of becoming a mentor, I learned about mentoring roles, discovered my vulnerabilities, and found a community of support. The improvements and understanding I gained through engaging in this study demonstrate that self-study can be beneficial for both mentor teachers and teacher educators to inform and increase knowledge in the field of mentoring.

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Choose Your Words: Refining What Counts As Mathematical Discourse In Students' Negotiation Of Meaning For Rate Of Change Of Volume, Christine Johnson Jul 2008

Choose Your Words: Refining What Counts As Mathematical Discourse In Students' Negotiation Of Meaning For Rate Of Change Of Volume, Christine Johnson

Theses and Dissertations

The purpose of this study is to describe how university honors calculus students negotiate meaning and language for conceptually important ideas through mathematical discourse. Mathematical discourse has been recognized as an important topic by mathematics education researchers of various theoretical perspectives. This study is written from a perspective that merges symbolic interactionism (Blumer, 1969) with personal agency (Walter & Gerson, 2007) to assert that human choice reflects, but is not determined by, meanings that are primarily developed through social interaction. The process of negotiation of meaning is identified, described, and analyzed in the discourse of four students and their professor …

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Secondhand Chinoiserie And The Confucian Revolutionary: Colonial America's Decorative Arts "After The Chinese Taste", Kiersten Claire Davis Jul 2008

Secondhand Chinoiserie And The Confucian Revolutionary: Colonial America's Decorative Arts "After The Chinese Taste", Kiersten Claire Davis

Theses and Dissertations

This thesis explores the implications of chinoiserie, or Western creations of Chinese-style decorative arts, upon an eighteenth century colonial American audience. Chinese products such as tea, porcelain, and silk, and goods such as furniture and wallpaper displaying Chinese motifs of distant exotic lands, had become popular commodities in Europe by the eighteenth century. The American colonists, who were primarily culturally British, thus developed a taste for chinoiserie fashions and wares via their European heritage. While most European countries had direct access to the China trade, colonial Americans were banned from any direct contact with the Orient by the British East …

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Rational Schur Rings Over Abelian Groups, Brent L. Kerby Jul 2008

Rational Schur Rings Over Abelian Groups, Brent L. Kerby

Theses and Dissertations

In 1993, Muzychuk showed that the rational S-rings over a cyclic group Z_n are in one-to-one correspondence with sublattices of the divisor lattice of n, or equivalently, with sublattices of the lattice of subgroups of Z_n. This idea is easily extended to show that for any finite group G, sublattices of the lattice of characteristic subgroups of G give rise to rational S-rings over G in a natural way. Our main result is that any finite group may be represented as the automorphism group of such a rational S-ring over an abelian p-group. In order to show this, we first …

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Homomorphisms Into The Fundamental Group Of One-Dimensional And Planar Peano Continua, Curtis Andrew Kent Jul 2008

Homomorphisms Into The Fundamental Group Of One-Dimensional And Planar Peano Continua, Curtis Andrew Kent

Theses and Dissertations

Let X be a planar or one-dimensional Peano continuum. Let E be a Hawaiian Earring with fundamental group H. We show that every homomorphism from H to the fundamental group of X is conjugate to a homomorphism which is induced by a continuous function.

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Ordinal Regression To Evaluate Student Ratings Data, Emily Brooke Bell Jul 2008

Ordinal Regression To Evaluate Student Ratings Data, Emily Brooke Bell

Theses and Dissertations

Student evaluations are the most common and often the only method used to evaluate teachers. In these evaluations, which typically occur at the end of every term, students rate their instructors on criteria accepted as constituting exceptional instruction in addition to an overall assessment. This presentation explores factors that influence student evaluations using the teacher ratings data of Brigham Young University from Fall 2001 to Fall 2006. This project uses ordinal regression to model the probability of an instructor receiving a good, average, or poor rating. Student grade, instructor status, class level, student gender, total enrollment, term, GE class status, …

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Arbitrary Degree T-Splines, Gordon Thomas Finnigan Jul 2008

Arbitrary Degree T-Splines, Gordon Thomas Finnigan

Theses and Dissertations

T-Splines is a freeform surface type similar to NURBS, that allows partial rows of control points. Up until now, T-Splines have only been formally defined for the degree three case. This paper extends the definition to support all odd, even, and mixed degree T-Spline surfaces, making T-Splines a proper superset of all standard NURBS surfaces.

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Optimumwater Allocation At Basin Scale Using Meta-Modeling, M. Shourian, S. Jamshid Mousavi Jul 2008

Optimumwater Allocation At Basin Scale Using Meta-Modeling, M. Shourian, S. Jamshid Mousavi

International Congress on Environmental Modelling and Software

Evolutionary optimization algorithms, in many cases, suffer from a high computational cost due to the high-fidelity simulation models performed for objective function evaluations. Meta-modeling is one of the useful approaches to overcome this problem in which a surrogate model, running of which is much faster than the exact model, is used in lieu of the simulation model. To build a meta-model it is required to use a function-approximation procedure by which the expensive simulation model is approximated. Artificial Neural Networks (ANNs), as meta-models, have shown different applicability in various engineering design problems. However, training ANNs needs enough input-output data (design …

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System Dynamics Modelling: A Tool For Participatory Simulation Of Complex Water Systems Within Aquastress, L. S. Vamvakeridou-Lyroudia, Dragan Savic Jul 2008

System Dynamics Modelling: A Tool For Participatory Simulation Of Complex Water Systems Within Aquastress, L. S. Vamvakeridou-Lyroudia, Dragan Savic

International Congress on Environmental Modelling and Software

System Dynamics Modelling (SDM) is a methodology for studying and managing complex feedback systems, typically used when formal analytical models do not exist, but system simulation can be developed by linking a number of feedback mechanisms. Forrester (1961) introduced system thinking and SDM in the early 60’s as a modelling and simulation methodology for long-term decision-making in dynamic industrial management problems. Since then, SDM has been applied to various business policy and strategy problems (Barlas 2002). Consequently it has proven to be very useful for the simulation and study of complex environmental (Ford 1999, Mulligan and Wainwright 2004) and water …

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Ecosystem Stability In Integrated Catchment Management, Peter A. Khaiter, Marina G. Erechtchoukova Jul 2008

Ecosystem Stability In Integrated Catchment Management, Peter A. Khaiter, Marina G. Erechtchoukova

International Congress on Environmental Modelling and Software

Freshwater is vital for human civilization. Growing population and societal development demand for more water resources. Freshwater is not considered globally scarce, but its distribution across the planet is not even and many countries suffer from water shortage. Human activities constantly produce an impact upon natural waters causing their destruction, degradation and pollution. Freshwater is a multi-purpose resource and this circumstance dictates a need to coordinate the interests of various water users. Integrated catchment management is a framework with the explicit objective to improve natural resources management on a catchment basis. Water resources are an integral part of ecosystems and …

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Thunderstorm Strike Probability Nowcasting, A New Algorithm, S. Dance, B. Ebert, D. Scurrah Jul 2008

Thunderstorm Strike Probability Nowcasting, A New Algorithm, S. Dance, B. Ebert, D. Scurrah

International Congress on Environmental Modelling and Software

Thunderstorm nowcasting is an important function for the severe weather forecaster. The usual method is for radar to detect thunderstorms, and for downstream systems to generate ’threat areas’ for issuing warnings. However, these threat areas are difficult for other systems to work with as they are not mathematically well defined. In this paper we develop an algorithm, THESPA (THunderstorm Environment Strike Probability Algorithm), to translate a radar thunderstorm detection into a ’strike probability’, a new concept for thunderstorm nowcasting. This represents the probability a given point will be affected by a thunderstorm in a given period. Being well defined, this …

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Developments In Urban Environmental Information Perception And Communication, Kostas Karatzas, J. Lee Jul 2008

Developments In Urban Environmental Information Perception And Communication, Kostas Karatzas, J. Lee

International Congress on Environmental Modelling and Software

Urban environmental information (EI) is related to knowledge concerning the status, the pressures and the consequences of environmental quality parameters to human life and the urban surroundings. One of the most important aspects in the life cycle of EI is knowledge generation and flow, data management and information dissemination between ICT systems and environmental actors, players, or interested parties. In the present paper, urban air quality serves as the application domain, for which the following issues are discussed, • Analysis of the way that environmental information is related to urban structures (roads, buildings, etc) • Investigation of the spatial and …

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Aqquastudy – Enabling Remote Access To Model-Based Software Tools For Supporting The Design And Operation Of Wwtps, I. Irizar, M. De Gracia Jul 2008

Aqquastudy – Enabling Remote Access To Model-Based Software Tools For Supporting The Design And Operation Of Wwtps, I. Irizar, M. De Gracia

International Congress on Environmental Modelling and Software

Making use of mathematical programming algorithms, a software library (AqLib) has been built for automatically optimising the design and operation of wastewater treatment plants. Currently, AqLib implements seven configurations for nitrogen removal (DN, DN2, RDN, SDN, DRDN, RSDN and DRSDN), five configurations for phosphorous removal (A2O, Bardenpho, Johannesburg, UCT and MUCT), and the anaerobic digestion process. Moreover, an Internet-based service (AqquaStudy) has been deployed so that AqLib can be remotely accessed from any standard web-browser.

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The Benchmark Simulation Models – A Valuable Collection Of Modelling Tools, John B. Copp, Ulf Jeppsson, Peter A. Vanrolleghem Jul 2008

The Benchmark Simulation Models – A Valuable Collection Of Modelling Tools, John B. Copp, Ulf Jeppsson, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Over a decade ago, the concept of a tool that could be used to objectivelyevaluate the performance of control strategies through simulation using a standard modelimplementation was introduced for activated sludge wastewater treatment plants. Thatconcept resulted in the development of the Benchmark Simulation Model No 1 (BSM1),the subsequent BSM1_LT and most recently BSM2. Debate about the need and applicationof these models has dogged the development effort since it first began with practitionerssuggesting that these models are only academically applicable, have been conceived of forpublication generation purposes and provide limited benefit to the applied modellingcommunity. The authors of this paper, as …

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Developing Bayesian Network Models Within A Risk Assessment Framework, C. A. Pollino, Barry T. Hart Jul 2008

Developing Bayesian Network Models Within A Risk Assessment Framework, C. A. Pollino, Barry T. Hart

International Congress on Environmental Modelling and Software

The risk assessment framework is increasingly being applied to examine both human and non-human stressors on ecological systems. Risk-based decision-making aims to quantify the likelihood of a threat occurring, the consequences of this to an ecological system, process or value, and the associated uncertainty in the predictions. Until recently, the ability to predict changes in dynamic ecosystems due to stressors was limited by both the poor understanding of the drivers of ecological processes and structure, and the lack of modelling tools that could represent such complexity with associated uncertainties. However, the recent growth in the use of Bayesian network tools …

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