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Full-Text Articles in Physical Sciences and Mathematics

Beyond Machine Learning: An Fmri Domain Adaptation Model For Multi-Study Integration, Lauryn Michelle Burleigh Mar 2023

Beyond Machine Learning: An Fmri Domain Adaptation Model For Multi-Study Integration, Lauryn Michelle Burleigh

LSU Doctoral Dissertations

Traditional machine learning analyses are challenging with functional magnetic
resonance imaging (fMRI) data, not only because of the amount of data that needs to be
collected, adding a particular challenge for human fMRI research, but also due to the change in
hypothesis being addressed with various analytical techniques. Domain adaptation is a type of
transfer learning, a step beyond machine learning which allows for multiple related, but not
identical, data to contribute to a model, can be beneficial to overcome the limitation of data
needed but may address different hypothesis questions than anticipated given the analysis
computation. This dissertation assesses …


Methodology Of Development Of Mathematical Models Of Information Processing Systems, Maruf Kuchimov Apr 2021

Methodology Of Development Of Mathematical Models Of Information Processing Systems, Maruf Kuchimov

Bulletin of TUIT: Management and Communication Technologies

Modeling as a research method is a powerful cognitive tool throughout the history of human development. The article describes the methodology for the development of mathematical models of information systems, based on materials from various literary sources, author's developments on the system approach, mathematical modeling and programming. The mathematical model of the information system is described and all the characteristics of the IS are given.


Wicked Ideas For Wicked Problems: Marine Debris And The Complexity Of Governance, Dawn Helene Driesbach Dec 2020

Wicked Ideas For Wicked Problems: Marine Debris And The Complexity Of Governance, Dawn Helene Driesbach

Graduate Program in International Studies Theses & Dissertations

Myriad challenges regarding earth's common spaces, those unregulated by sovereign state authorities, mount and intensify as resources diminish and competition for commercial, scientific and security advantages increases; the pollution and degradation of those spaces simultaneously expands. Threats to the global commons complicate efforts to achieve international consensus which impedes attempts to develop effective governance. As an example, marine debris is a growing problem and is an existential threat to the global commons.

This dissertation aims to characterize marine debris as a wicked problem and explores the complexity of governance in the global ocean commons by answering two fundamental questions. Under …


Dynamical Climatic Model For Time To Flowering In Vigna Radiata, Konstantin Kozlov, Alena Sokolkova, Cheng Ruei Lee, Chau Ti Ting, Roland Schafleitner, Eric Bishop-Von Wettberg, Sergey Nuzhdin, Maria Samsonova Oct 2020

Dynamical Climatic Model For Time To Flowering In Vigna Radiata, Konstantin Kozlov, Alena Sokolkova, Cheng Ruei Lee, Chau Ti Ting, Roland Schafleitner, Eric Bishop-Von Wettberg, Sergey Nuzhdin, Maria Samsonova

College of Agriculture and Life Sciences Faculty Publications

Background: Phenology data collected recently for about 300 accessions of Vigna radiata (mungbean) is an invaluable resource for investigation of impacts of climatic factors on plant development. Results: We developed a new mathematical model that describes the dynamic control of time to flowering by daily values of maximal and minimal temperature, precipitation, day length and solar radiation. We obtained model parameters by adaptation to the available experimental data. The models were validated by cross-validation and used to demonstrate that the phenology of adaptive traits, like flowering time, is strongly predicted not only by local environmental factors but also by plant …


Garch Modeling Of Value At Risk And Expected Shortfall Using Bayesian Model Averaging, Ismail Kheir Aug 2019

Garch Modeling Of Value At Risk And Expected Shortfall Using Bayesian Model Averaging, Ismail Kheir

Theses and Dissertations

This thesis conducts Value at Risk (VaR) and Expected Shortfall (ES) estimation using GARCH modeling and Bayesian Model Averaging (BMA). BMA considers multiple models weighted by some information criterion. Through BMA, this thesis finds that VaR and ES estimates can be improved through enhanced modeling of the data generation process.


Measure Of Departure From Marginal Average Point-Symmetry For Two-Way Contingency Tables, Kiyotaka Iki, Sadao Tomizawa Jun 2019

Measure Of Departure From Marginal Average Point-Symmetry For Two-Way Contingency Tables, Kiyotaka Iki, Sadao Tomizawa

Journal of Modern Applied Statistical Methods

For the analysis of two-way contingency tables with ordered categories, Yamamoto, Tahata, Suzuki, and Tomizawa (2011) considered a measure to represent the degree of departure from marginal point-symmetry. The maximum value of the measure cannot distinguish two kinds of marginal complete asymmetry with respect to the midpoint. A measure is proposed which can distinguish two kinds of marginal asymmetry with respect to the midpoint. It also gives large-sample confidence interval for the proposed measure.


Non-Linear Regression Models For Time To Flowering In Wild Chickpea Combine Genetic And Climatic Factors, Konstantin Kozlov, Anupam Singh, Jens Berger, Eric Bishop-Von Wettberg, Abdullah Kahraman, Abdulkadir Aydogan, Douglas Cook, Sergey Nuzhdin, Maria Samsonova Mar 2019

Non-Linear Regression Models For Time To Flowering In Wild Chickpea Combine Genetic And Climatic Factors, Konstantin Kozlov, Anupam Singh, Jens Berger, Eric Bishop-Von Wettberg, Abdullah Kahraman, Abdulkadir Aydogan, Douglas Cook, Sergey Nuzhdin, Maria Samsonova

College of Agriculture and Life Sciences Faculty Publications

Background: Accurate prediction of crop flowering time is required for reaching maximal farm efficiency. Several models developed to accomplish this goal are based on deep knowledge of plant phenology, requiring large investment for every individual crop or new variety. Mathematical modeling can be used to make better use of more shallow data and to extract information from it with higher efficiency. Cultivars of chickpea, Cicer arietanum, are currently being improved by introgressing wild C. reticulatum biodiversity with very different flowering time requirements. More understanding is required for how flowering time will depend on environmental conditions in these cultivars developed by …


Characterizing Landscape-Scale Erosion Using 10be In Detrital Fluvial Sediment: Slope-Based Sampling Strategy Detects The Effect Of Widespread Dams, Lucas J. Reusser, Paul R. Bierman, Donna M. Rizzo, Eric W. Portenga, Dylan H. Rood May 2017

Characterizing Landscape-Scale Erosion Using 10be In Detrital Fluvial Sediment: Slope-Based Sampling Strategy Detects The Effect Of Widespread Dams, Lucas J. Reusser, Paul R. Bierman, Donna M. Rizzo, Eric W. Portenga, Dylan H. Rood

College of Engineering and Mathematical Sciences Faculty Publications

Concentrations of in situ 10Be measured in detrital fluvial sediment are frequently used to estimate long-term erosion rates of drainage basins. In many regions, basin-averaged erosion rates are positively correlated with basin average slope. The slope dependence of erosion allows model-based erosion rate estimation for unsampled basins and basins where human disturbance may have biased cosmogenic nuclide concentrations in sediment. Using samples collected from southeastern North America, we demonstrate an approach that explicitly considers the relationship between average basin slope and erosion rate. Because dams and reservoirs are ubiquitous on larger channels in the field area, we selected 36 undammed …


An Exposition And Calibration Of The Ho-Lee Model Of Interest Rates, Benjamin I. Lawson Jan 2015

An Exposition And Calibration Of The Ho-Lee Model Of Interest Rates, Benjamin I. Lawson

CMC Senior Theses

The purpose of this paper is to create an easily understandable version of the Ho-Lee interest rate model. The first part analyzes the model in detail, and the second part calibrates it to demonstrate how it can be applied to real market data.


Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta Nov 2013

Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta

Danielle Skropeta

In this study a series of isatin-based, pH-sensitive aryl imine derivatives with differing aromatic substituents and substitution patterns were synthesised and their acid-catalysed hydrolysis evaluated. These derivatives were functionalised at the C3 carbonyl group of a potent N-substituted isatin cytotoxin and were stable at physiological pH but readily cleaved at pH 4.5. Observed rates of hydrolysis for the embedded imine-acid moiety were in the order para-phenylpropionic acid>phenylacetic acid (para>meta)>benzoic acid (meta>para). The ability to fine-tune hydrolysis rates in this way has potential implications for optimising imine linked, tumour targeting cytotoxin-protein conjugates


On Comparison Of Exponential And Hyperbolic Exponential Growth Models In Height/Diameter Increment Of Pines (Pinus Caribaea), S. O. Oyamakin, A. U. Chukwu, T. A. Bamiduro Nov 2013

On Comparison Of Exponential And Hyperbolic Exponential Growth Models In Height/Diameter Increment Of Pines (Pinus Caribaea), S. O. Oyamakin, A. U. Chukwu, T. A. Bamiduro

Journal of Modern Applied Statistical Methods

A new tree growth model called the hyperbolic exponential nonlinear growth model is suggested. Its ability in model prediction was compared with the Malthus or exponential growth model an approach which mimicked the natural variability of heights/diameter increment with respect to age and therefore provides more realistic height/diameter predictions as demonstrated by the results of the Kolmogorov Smirnov test and Shapiro-Wilk test. The mean function of top height/Dbh over age using the two models under study predicted closely the observed values of top height/Dbh in the Hyperbolic exponential nonlinear growth models better than the ordinary exponential growth model without violating …


A Unified Model For Topics, Events And Users On Twitter, Qiming Diao, Jing Jiang Oct 2013

A Unified Model For Topics, Events And Users On Twitter, Qiming Diao, Jing Jiang

Research Collection School Of Computing and Information Systems

With the rapid growth of social media, Twitter has become one of the most widely adopted platforms for people to post short and instant message. On the one hand, people tweets about their daily lives, and on the other hand, when major events happen, people also follow and tweet about them. Moreover, people’s posting behaviors on events are often closely tied to their personal interests. In this paper, we try to model topics, events and users on Twitter in a unified way. We propose a model which combines an LDA-like topic model and the Recurrent Chinese Restaurant Process to capture …


Assessing Soil Remobilisation In Catchments Using A 137 Cs-Sediment Hillslope Model, Ava D. Simms, Colin D. Woodroffe, Brian G. Jones, Henk Heijnis, Jennifer Harrison, Rob Mann Jun 2013

Assessing Soil Remobilisation In Catchments Using A 137 Cs-Sediment Hillslope Model, Ava D. Simms, Colin D. Woodroffe, Brian G. Jones, Henk Heijnis, Jennifer Harrison, Rob Mann

B. G. Jones

Soil redistribution studies are important, especially in water supply catchments, because the rate at which denudation is occurring has implications for offsite water quality. However, the extent to which soil is redistributed within the landscape can be difficult to determine. This challenge can be overcome using fallout caesium-137 (137Cs). This paper describes the rates of soil loss and remobilisation in two sub-catchments within the Sydney Basin region, namely Kembla and Kentish Creeks, which drain to the Cordeaux reservoir. The total inventories of 137Cs in catchment soils were determined, a 137Cs-regression equation and a theoretical diffusion and migration model were used …


A Latent Variable Model For Viewpoint Discovery From Threaded Forum Posts, Minghui Qiu, Jing Jiang Jun 2013

A Latent Variable Model For Viewpoint Discovery From Threaded Forum Posts, Minghui Qiu, Jing Jiang

Research Collection School Of Computing and Information Systems

Threaded discussion forums provide an important social media platform. Its rich user generated content has served as an important source of public feedback. To automatically discover the viewpoints or stances on hot issues from forum threads is an important and useful task. In this paper, we propose a novel latent variable model for viewpoint discovery from threaded forum posts. Our model is a principled generative latent variable model which captures three important factors: viewpoint specific topic preference, user identity and user interactions. Evaluation results show that our model clearly outperforms a number of baseline models in terms of both clustering …


Assessment Of Length Distributions Between Non-Coding And Coding Sequences Amongst Two Model Organisms, Ren Zhang, Rachel Caldwell, Yan-Xia Lin Nov 2012

Assessment Of Length Distributions Between Non-Coding And Coding Sequences Amongst Two Model Organisms, Ren Zhang, Rachel Caldwell, Yan-Xia Lin

Associate Professor Yan-Xia Lin

No abstract provided.


Flexible Free-Standing Carbon Nanotube Films For Model Lithium-Ion Batteries, Jun Chen, Sau Yen Chew, See How Ng, Jiazhao Wang, Hua Liu, P Novak, F Krumeich, Shulei Chou Nov 2012

Flexible Free-Standing Carbon Nanotube Films For Model Lithium-Ion Batteries, Jun Chen, Sau Yen Chew, See How Ng, Jiazhao Wang, Hua Liu, P Novak, F Krumeich, Shulei Chou

Shulei Chou

No abstract provided.


Chemical Cross-Linking Of The Chloroplast Localized Small Heat-Shock Protein, Hsp21, And The Model Substrate Citrate Synthase, Emma Ahrman, W Lambert, Andrew Aquilina, C V Robinson, Cs Emanuelsson Oct 2012

Chemical Cross-Linking Of The Chloroplast Localized Small Heat-Shock Protein, Hsp21, And The Model Substrate Citrate Synthase, Emma Ahrman, W Lambert, Andrew Aquilina, C V Robinson, Cs Emanuelsson

J. A. Aquilina

The molecular mechanism whereby the small heat-shock protein (sHsp) chaperones interact with and prevent aggregation of other proteins is not fully understood. We have characterized the sHsp-substrate protein interaction at normal and increased temperatures utilizing a model substrate protein, citrate synthase (CS), widely used in chaperone assays, and a dodecameric plant sHsp, Hsp21, by chemical cross-linking with 3,3'-Dithiobis[sulfosuccinimidylpropionate] (DTSSP) and mass spectrometric peptide mapping. In the absence of CS, the cross-linker captured Hsp21 in dodecameric form, even at increased temperature (47 degrees C). In the presence of equimolar amounts of CS, no Hsp21 dodecamer was captured, indicating a substrate-induced Hsp21 …


Atmospheric Greenhouse Gases Retrieved From Sciamachy: Comparison To Ground-Based Fts Measurements And Model Results, O Schneising, P Bergamaschi, H Bovensmann, M Buchwitz, J P. Burrows, N M. Deutscher, D W. T Griffith, J Heymann, R Macatangay, J Messerschmidt, J Notholt, M Rettinger, M Reuter, R Sussmann, Voltaire A. Velazco, T Warneke, P O. Wennberg, D Wunch Jan 2012

Atmospheric Greenhouse Gases Retrieved From Sciamachy: Comparison To Ground-Based Fts Measurements And Model Results, O Schneising, P Bergamaschi, H Bovensmann, M Buchwitz, J P. Burrows, N M. Deutscher, D W. T Griffith, J Heymann, R Macatangay, J Messerschmidt, J Notholt, M Rettinger, M Reuter, R Sussmann, Voltaire A. Velazco, T Warneke, P O. Wennberg, D Wunch

Faculty of Science - Papers (Archive)

SCIAMACHY onboard ENVISAT (launched in 2002) enables the retrieval of global long-term columnaveraged dry air mole fractions of the two most important anthropogenic greenhouse gases carbon dioxide and methane (denoted XCO2 and XCH4). In order to assess the quality of the greenhouse gas data obtained with the recently introduced v2 of the scientific retrieval algorithm WFM-DOAS, we present validations with ground-based Fourier Transform Spectrometer (FTS) measurements and comparisons with model results at eight Total Carbon Column Observing Network (TCCON) sites providing realistic error estimates of the satellite data. Such validation is a prerequisite to assess the suitability …


Atmospheric Carbon Dioxide Retrieved From The Greenhouse Gases Observing Satellite (Gosat): Comparison With Ground-Based Tccon Observations And Geos-Chem Model Calculations, A Cogan, H Boesch, R Parker, L Feng, Paul Palmer, J-F Blavier, Nicholas M. Deutscher, Ronald Macatangay, Justus Notholt, C M. Roehl, Thorsten Warneke, Debra Wunch Jan 2012

Atmospheric Carbon Dioxide Retrieved From The Greenhouse Gases Observing Satellite (Gosat): Comparison With Ground-Based Tccon Observations And Geos-Chem Model Calculations, A Cogan, H Boesch, R Parker, L Feng, Paul Palmer, J-F Blavier, Nicholas M. Deutscher, Ronald Macatangay, Justus Notholt, C M. Roehl, Thorsten Warneke, Debra Wunch

Faculty of Science - Papers (Archive)

We retrieved column-averaged dry air mole fractions of atmospheric carbon dioxide (XCO 2) from backscattered short-wave infrared (SWIR) sunlight measured by the Japanese Greenhouse gases Observing SATellite (GOSAT). Over two years of XCO 2 retrieved from GOSAT is compared with XCO 2 inferred from collocated SWIR measurements by seven ground-based Total Carbon Column Observing Network (TCCON) stations. The average difference between GOSAT and TCCON XCO 2 for individual TCCON sites ranges from -0.87 ppm to 0.77 ppm with a mean value of 0.1 ppm and standard deviation of 0.56 ppm. We find an average bias between all GOSAT and TCCON …


Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal Dec 2011

Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal

Heath Ecroyd

The amorphous aggregation of proteins is associated with many phenomena, ranging from the formation of protein wine haze to the development of cataract in the eye lens and the precipitation of recombinant proteins during their expression and purification. While much literature exists describing models for linear protein aggregation, such as amyloid fibril formation, there are few reports of models which address amorphous aggregation. Here, we propose a model to describe the amorphous aggregation of proteins which is also more widely applicable to other situations where a similar process occurs, such as in the formation of colloids and nanoclusters. As first …


A Financial Impact Assessment Of Ld 1725: Stream Crossings, New England Environmental Finance Center, Muskie School Of Public Service Jan 2011

A Financial Impact Assessment Of Ld 1725: Stream Crossings, New England Environmental Finance Center, Muskie School Of Public Service

Water

This report looks at the potential financial impact of LD 1725 on the estimated 30,000 stream crossings in the State of Maine that would be affected by the law. Our research for this report included the analysis of nearly 2000 stream crossings and the data collection necessary for the development of extensive stream crossing replacement cost models. We found that the 1.2 bankfull requirements in LD 1725 would result in a 75% ‐ 250% increase in structure widths for stream crossing projects across the state. An upsize of this magnitude would increase the cost of replacing stream crossings statewide by …


A Financial Impact Assessment Of Ld 1725: Stream Crossings (Presentation), New England Environmental Finance Center, Muskie School Of Public Service Jan 2011

A Financial Impact Assessment Of Ld 1725: Stream Crossings (Presentation), New England Environmental Finance Center, Muskie School Of Public Service

Water

This report looks at the potential financial impact of LD 1725 on the estimated 30,000 stream crossings in the State of Maine that would be affected by the law. Our research for this report included the analysis of nearly 2000 stream crossings and the data collection necessary for the development of extensive stream crossing replacement cost models. We found that the 1.2 bankfull requirements in LD 1725 would result in a 75% ‐ 250% increase in structure widths for stream crossing projects across the state. An upsize of this magnitude would increase the cost of replacing stream crossings statewide by …


Daily And 3-Hourly Variability In Global Fire Emissions And Consequences For Atmospheric Model Predictions Of Carbon Monoxide, M Mu, James Randerson, G R. Van Der Werf, L Giglio, Prasad Kasibhatla, D Morton, G J. Collatz, R S. Defries, E J. Hyer, E M. Prins, David W. Griffith, Debra Wunch, G C. Toon, V Sherlock, Paul O. Wennberg Jan 2011

Daily And 3-Hourly Variability In Global Fire Emissions And Consequences For Atmospheric Model Predictions Of Carbon Monoxide, M Mu, James Randerson, G R. Van Der Werf, L Giglio, Prasad Kasibhatla, D Morton, G J. Collatz, R S. Defries, E J. Hyer, E M. Prins, David W. Griffith, Debra Wunch, G C. Toon, V Sherlock, Paul O. Wennberg

Faculty of Science - Papers (Archive)

"Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic-and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We disaggregated monthly GFED3 emissions during 2003-2009 to a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) active fire observations. Daily variability …


Methane Observations From The Greenhouse Gases Observing Satellite: Comparison To Ground-Based Tccon Data And Model Calculations, Robert Parker, Hartmut Boesch, Austin Cogan, Annemarie Fraser, Liang Feng, Paul Palmer, Janina Messerschmidt, Nicholas M. Deutscher, David W. Griffith, Justus Notholt, Paul O. Wennberg, Debra Wunch Jan 2011

Methane Observations From The Greenhouse Gases Observing Satellite: Comparison To Ground-Based Tccon Data And Model Calculations, Robert Parker, Hartmut Boesch, Austin Cogan, Annemarie Fraser, Liang Feng, Paul Palmer, Janina Messerschmidt, Nicholas M. Deutscher, David W. Griffith, Justus Notholt, Paul O. Wennberg, Debra Wunch

Faculty of Science - Papers (Archive)

We report new short-wave infrared (SWIR) column retrievals of atmospheric methane (X CH4) from the Japanese Greenhouse Gases Observing SATellite (GOSAT) and compare observed spatial and temporal variations with correlative ground-based measurements from the Total Carbon Column Observing Network (TCCON) and with the global 3-D GEOS-Chem chemistry transport model. GOSAT X CH4 retrievals are compared with daily TCCON observations at six sites between April 2009 and July 2010 (Bialystok, Park Falls, Lamont, Orleans, Darwin and Wollongong). GOSAT reproduces the site-dependent seasonal cycles as observed by TCCON with correlations typically between 0.5 and 0.7 with an estimated single-sounding precision between 0.4-0.8%. …


Retrieval Of Atmospheric Co2 With Enhanced Accuracy And Precision From Sciamachy: Validation With Fts Measurements And Comparison With Model Results, M Reuter, H Bovensmann, M Buchwitz, Jp Burrows, B Connor, Nicholas M. Deutscher, David W. Griffith, J Heymann, Gretchen Keppel-Aleks, Janina Messerschmidt, Justus Notholt, Christof Petri, J Robinson, O Schneising, V Sherlock, Voltaire A. Velazco, Thorsten Warneke, Paul O. Wennberg, Debra Wunch Jan 2011

Retrieval Of Atmospheric Co2 With Enhanced Accuracy And Precision From Sciamachy: Validation With Fts Measurements And Comparison With Model Results, M Reuter, H Bovensmann, M Buchwitz, Jp Burrows, B Connor, Nicholas M. Deutscher, David W. Griffith, J Heymann, Gretchen Keppel-Aleks, Janina Messerschmidt, Justus Notholt, Christof Petri, J Robinson, O Schneising, V Sherlock, Voltaire A. Velazco, Thorsten Warneke, Paul O. Wennberg, Debra Wunch

Faculty of Science - Papers (Archive)

The Bremen Optimal Estimation differential optical absorption spectroscopy (DOAS) (BESD) algorithm for satellite based retrievals of XCO 2 (the column-average dry-air mole fraction of atmospheric CO 2) has been applied to Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) data. It uses measurements in the O 2-A absorption band to correct for scattering of undetected clouds and aerosols. Comparisons with precise and accurate ground-based Fourier transform spectrometer (FTS) measurements at four Total Carbon Column Observing Network (TCCON) sites have been used to quantify the quality of the new SCIAMACHY XCO 2 data set. Additionally, the results have been compared to …


The Australian Methane Budget: Interpreting Surface And Train-Borne Measurements Using A Chemistry Transport Model, A Fraser, C C. Miller, Paul Palmer, Nicholas M. Deutscher, Nicholas B. Jones, David W. Griffith Jan 2011

The Australian Methane Budget: Interpreting Surface And Train-Borne Measurements Using A Chemistry Transport Model, A Fraser, C C. Miller, Paul Palmer, Nicholas M. Deutscher, Nicholas B. Jones, David W. Griffith

Faculty of Science - Papers (Archive)

We investigate the Australian methane budget from 2005-2008 using the GEOS-Chem 3D chemistry transport model, focusing on the relative contribution of emissions from different sectors and the influence of long-range transport. To evaluate the model, we use in situ surface measurements of methane, methane dry air column average (XCH 4) from ground-based Fourier transform spectrometers (FTSs), and train-borne surface concentration measurements from an in situ FTS along the north-south continental transect. We use gravity anomaly data from Gravity Recovery and Climate Experiment to describe the spatial and temporal distribution of wetland emissions and scale it to a prior emission estimate, …


Culvert Material Cost Comparison, New England Environmental Finance Center Nov 2010

Culvert Material Cost Comparison, New England Environmental Finance Center

Water

The following tables provide a detailed look at the role that culvert material and culvert diameter play in the overall cost of a culvert replacement project.


Application Of A Simple Hydrodynamic Model To Estuary Entrance Management, Errol J. Mclean, Jon B. Hinwood Jan 2010

Application Of A Simple Hydrodynamic Model To Estuary Entrance Management, Errol J. Mclean, Jon B. Hinwood

Faculty of Science - Papers (Archive)

Tidal inlets which link a tidal basin to the sea via a constricted entrance are common on the south-east Australian coast. Closure, or even significant constriction, raises water levels but restricts tidal range within the basin, while open entrances provide regular and significant tidal exchange with the ocean. A rapid assessment procedure with minimal data requirements has been shown to be informative for monitoring and a useful component of any Decision Support System set up as part of a management structure. Such a system is presented in this paper. It is based on one permanent water level gauge inside the …


Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson Jan 2010

Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson

Faculty of Science - Papers (Archive)

In this paper we describe a new method for estimating trace gas emissions from large vegetation fires using satellite measurements of aerosol optical depth (AOD) at 550 nm, combined with an atmospheric chemical transport model. The method uses a threshold value to screen out normal levels of AOD that may be caused by raised dust, sea salt aerosols or diffuse smoke transported from distant fires. Using this method we infer an estimated total emission of 15±5 Tg of carbon monoxide, 0.05±0.02 Tg of hydrogen cyanide, 0.11±0.03 Tg of ammonia, 0.25±0.07 Tg of formaldehyde, 0.03±0.01 of acetylene, 0.10±0.03 Tg of ethylene, …


The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar Jan 2010

The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar

Faculty of Science - Papers (Archive)

This study presents a synthetic model intercomparison to investigate the importance of transport model errors for estimating the sources and sinks of CO2 using satellite measurements. The experiments were designed for testing the potential performance of the proposed CO2 lidar A-SCOPE, but also apply to other space borne missions that monitor total column CO2. The participating transport models IFS, LMDZ, TM3, and TM5 were run in forward and inverse mode using common CO2 fluxes and initial concentrations. Simulated column averaged CO2 (xCO 2) mixing ratios vary between the models by σCombining double low line0.5 ppm over the continents and σCombining …