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Statistical Methods For Automatic Crack Detection Based On Vibrothermography Sequence-Of-Images Data, Ming Li, Stephen D. Holland, William Q. Meeker 2010 Iowa State University

Statistical Methods For Automatic Crack Detection Based On Vibrothermography Sequence-Of-Images Data, Ming Li, Stephen D. Holland, William Q. Meeker

Statistics Preprints

Vibrothermography is a relatively new nondestructive evaluation technique for finding cracks through frictional heat generated from crack surface vibrations under external excitations. The vibrothermography inspection method provides a sequence of infrared images as output. We use a matched filter technique to increase the signal-to-noise ratio of the sequence-of-images data. An automatic crack detection criterion based on the features extracted from the matched filter output greatly increases the sensitivity of the vibrothermography inspection method. In this paper, we develop a three dimensional matched filter for the sequence-of-images data, present the statistical analysis for the matched filter output, and evaluate the probability ...


A Comparison Of Maximum Likelihood And Median Rank Regression For Weibull Estimation, Ulrike Genschel, William Q. Meeker 2010 Iowa State University

A Comparison Of Maximum Likelihood And Median Rank Regression For Weibull Estimation, Ulrike Genschel, William Q. Meeker

Statistics Preprints

The Weibull distribution is frequently used in reliability applications. Many different methods of estimating the parameters and important functions of the parameters (e.g. quantiles and failure probabilities) have been suggested. Maximum likelihood and median rank regression methods are most commonly used today. Largely because of conflicting results from different studies that have been conducted to investigate the properties of these estimators, there are sharp differences of opinion on which method should be used. The purpose of this paper is to report on the results of our simulation study, to provide insight into the differences between the competing methods, and ...


Mining Antagonistic Communities From Social Networks, Kuan ZHANG, David LO, Ee Peng LIM 2010 Singapore Management University

Mining Antagonistic Communities From Social Networks, Kuan Zhang, David Lo, Ee Peng Lim

Research Collection School Of Information Systems

During social interactions in a community, there are often sub-communities that behave in opposite manner. These antagonistic sub-communities could represent groups of people with opposite tastes, factions within a community distrusting one another, etc. Taking as input a set of interactions within a community, we develop a novel pattern mining approach that extracts for a set of antagonistic sub-communities. In particular, based on a set of user specified thresholds, we extract a set of pairs of sub-communities that behave in opposite ways with one another. To prevent a blow up in these set of pairs, we focus on extracting a ...


Prediction Of Protein Subcellular Localization: A Machine Learning Approach, Kyong Jin SHIM 2010 Singapore Management University

Prediction Of Protein Subcellular Localization: A Machine Learning Approach, Kyong Jin Shim

Research Collection School Of Information Systems

Subcellular localization is a key functional characteristic of proteins. Optimally combining available information is one of the key challenges in today's knowledge-based subcellular localization prediction approaches. This study explores machine learning approaches for the prediction of protein subcellular localization that use resources concerning Gene Ontology and secondary structures. Using the spectrum kernel for feature representation of amino acid sequences and secondary structures, we explore an SVM-based learning method that classifies six subcellular localization sites: endoplasmic reticulum, extracellular, Golgi, membrane, mitochondria, and nucleus.


Information Hiding Using Stochastic Diffusion For The Covert Transmission Of Encrypted Images, Jonathan Blackledge 2010 Dublin Institute of Technology

Information Hiding Using Stochastic Diffusion For The Covert Transmission Of Encrypted Images, Jonathan Blackledge

Conference papers

A principal weakness of all encryption systems is that the output data can be `seen' to be encrypted. In other words, encrypted data provides a 'flag' on the potential value of the information that has been encrypted. In this paper, we provide a novel approach to `hiding' encrypted data in a digital image. We consider an approach in which a plaintext image is encrypted with a cipher using the processes of `stochastic diffusion' and the output quantized into a 1-bit array generating a binary image cipher-text. This output is then `embedded' in a host image which is undertaken either in ...


Comparison Of Two Potential Streamgage Locations On Scott Creek At Swanton Pacific Ranch, California, Matthew C. Scrudato 2010 California Polytechnic State University - San Luis Obispo

Comparison Of Two Potential Streamgage Locations On Scott Creek At Swanton Pacific Ranch, California, Matthew C. Scrudato

Master's Theses and Project Reports

Two locations on Scott Creek, located 12 miles north of Santa Cruz California, are being considered for the installation of a streamgage to measure discharge. Each location offers unique considerations and challenges in gage construction and discharge measurement capabilities. A detailed flood frequency analysis was completed using a direct watershed comparison, direct equations developed by Waananen and Crippen, a Log Pearson Type III Frequency Distribution, a regional analysis, and two-station comparisons. Final results indicate a 100-year recurrence interval of 6,310 ft3/s at the Upper Scott Creek location and 6,520 ft3/s at the lower location. A detailed ...


Water Quality Outreach And Education Strategies For Northwest Arkansas And Regional Watersheds, Katie Teague, John Pennington 2010 Cooperative Extension Service

Water Quality Outreach And Education Strategies For Northwest Arkansas And Regional Watersheds, Katie Teague, John Pennington

Technical Reports

Stakeholders impact water quality and have a responsibility to protect, maintain, and improve water quality throughout northwest Arkansas and watersheds everywhere. But unless the roles of responsibility and stewardship among all stakeholders is communicated clearly and repetitively, there will be little progress made towards maintaining and improving water quality, while lawsuits, blame, and inaction will persist. Thus, the overall goal of water quality education and outreach is to improve the ability of stakeholders to take care of their watershed by teaching them what actions are or are not beneficial for water quality protection, maintenance, or improvements. Specific outreach and education ...


Water Quality And Watershed Conditions In The Upper Illinois River Watershed, Brian Haggard, Andrew Sharpley, Leslie Massey 2010 University of Arkansas, Fayetteville

Water Quality And Watershed Conditions In The Upper Illinois River Watershed, Brian Haggard, Andrew Sharpley, Leslie Massey

Technical Reports

The Illinois River and its tributaries have many uses that have been designated by the Arkansas Department of Environmental Quality including fisheries, aquatic life, primary contact waters, secondary contact waters, drinking water supply, and agricultural and industrial water supply, and water quality affects whether these uses can be supported. Since water quality can be quite complex, many types of measurements can be used as water quality indicators; some common water quality measurements include pH, dissolved oxygen concentration, and conductivity. More complicated measurements include determining nutrients, sediment and bacteria in the water, as well as assessing the aquatic life—aquatic insects ...


Regulatory Drivers For The Upper Illinois River And Other Regional Watersheds, Ray Weida 2010 FTN Associates, Ltd

Regulatory Drivers For The Upper Illinois River And Other Regional Watersheds, Ray Weida

Technical Reports

Environmental regulations are put in place to protect the air, water and land from threat of pollution. Regulatory programs establish pollution limits, determine compliance, and enforce environmental laws and regulations for waterbodies within the watershed based on the designated uses for the individual waterbody. These established regulations make sure that the state’s mandatory standards for clean water and the minimum federal standards are being achieved. Environmental regulations are established on both the federal and state levels. On the federal level, Congress has authorized the U.S. Environmental Protection Agency and other governmental agencies to create and enforce regulations. The ...


A Vision For The Upper Illinois River Watershed, Kent Thornton 2010 FTN Associates, Ltd

A Vision For The Upper Illinois River Watershed, Kent Thornton

Technical Reports

The Upper Illinois River Watershed is a special place where the threads of private, public and non‐profit partnerships are woven into the regional fabric of economic vitality; environmental stability, and social responsibility. Through its cultural heritage, the legacy of land stewardship, integrated with respect for personal property rights, continues. Natural resources are restored and sustained within a healthy mosaic of fields, forests, farms, woodlands, wetland prairies, pastures, cities, and naturally flowing streams. It is an incubator for green energy, entrepreneurial, educational and environmental initiatives.


Handbook Of Best Management Practices For The Upper Illinois River Watershed And Other Regional Watersheds, B.E. Haggard, Andrew Sharpley, Leslie Massey 2010 University of Arkansas, Fayetteville

Handbook Of Best Management Practices For The Upper Illinois River Watershed And Other Regional Watersheds, B.E. Haggard, Andrew Sharpley, Leslie Massey

Technical Reports

Management actions are strategies carried out by stakeholders that are designed to implement water quality protection and restoration activities with a watershed. This publication presents a range of beneficial management actions from simple to complex that address the pollutant potential that is common across the watershed landscape of northwest Arkansas. Some management actions can be undertaken by any watershed stakeholder at any time, while others need to be carefully planned or lobbied to local and state government. The following chapters address potential management actions that can be taken by individuals or groups at households, businesses, institutions, municipalities, industrial facilities, farms ...


Enrichments Of Heavy Sulfur (34s) In Sulfide Minerals: Gas Hydrates, Methane Delivery, And Anaerobic Methane Oxidation, Walter S. Borowski, Namcy M. Rodriguez, Charles K. Paull, William Ussler III 2010 Eastern Kentucky University

Enrichments Of Heavy Sulfur (34s) In Sulfide Minerals: Gas Hydrates, Methane Delivery, And Anaerobic Methane Oxidation, Walter S. Borowski, Namcy M. Rodriguez, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

The sulfur isotopic composition of authigenic, sedimentary sulfide minerals is largely controlled by sulfate reduction and related processes within sedimentary environments. Histograms show that that d34S values of sulfide minerals forming in depositional and diagenetic environments are most often negative (d34S < 0o/oo CDT) reflecting the original isotopic composition of seawater sulfate (now ~21o/oo), microbially-mediated fractionations of ~-8 to -40o/oo (a = 1.029-1.059) during sulfate reduction, and more extreme fractionations caused by sulfur disproportionation. Enrichments of heavy sulfur (d34S > 0o/oo) in sulfide minerals represent about 18% of ...


Xiap Impairs Smac Release From The Mitochondria During Apoptosis., Lorna Flanagan, Jordi Sebastia, Liam P. Tuffy, Aidan Spring, A Lichawska, Marc Devocelle, Jochen HM Prehn, Markus Rehm 2010 Royal College of Surgeons in Ireland

Xiap Impairs Smac Release From The Mitochondria During Apoptosis., Lorna Flanagan, Jordi Sebastia, Liam P. Tuffy, Aidan Spring, A Lichawska, Marc Devocelle, Jochen Hm Prehn, Markus Rehm

Physiology and Medical Physics Articles

X-linked inhibitor of apoptosis protein (XIAP) is a potent inhibitor of caspases 3, 7 and 9, and mitochondrial Smac (second mitochondria-derived activator of caspase) release during apoptosis inhibits the activity of XIAP. In this study we show that cytosolic XIAP also feeds back to mitochondria to impair Smac release. We constructed a fluorescent XIAP-fusion protein by labelling NH(2)- and COOH-termini with Cerulean fluorescent protein (C-XIAP-C). Immunoprecipitation confirmed that C-XIAP-C retained the ability to interact with Smac and impaired extrinsically and intrinsically activated apoptosis in response to tumour necrosis factor-related apoptosis-inducing ligand/cycloheximide and staurosporine. In C-XIAP-C-expressing cells, cytochrome c ...


An Organizational Maturity Model Of Software Product Line Engineering, Faheem Ahmed, Luiz Fernando Capretz 2010 Thompson River University

An Organizational Maturity Model Of Software Product Line Engineering, Faheem Ahmed, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

Software product line engineering is an inter-disciplinary concept. It spans the dimensions of business, architecture, process, and the organization. Some of the potential benefits of this approach include cost reduction, improvements in product quality and a decrease in product development time. The increasing popularity of software product line engineering in the software industry necessitates a process maturity evaluation methodology. Accordingly, this paper presents an organizational maturity model of software product line engineering for evaluating the maturity of organizational dimension. The model assumes that organizational theories, behavior, and management play a critical role in the institutionalization of software product line engineering ...


Impacts Of Individual Tree Species On Carbon Dynamics In A Moist Tropical Forest Environment, Ann E. Russell, James W. Raich, Ricardo Bedoya Arrieta, Oscar Valverde-Barrantes, Eugenio González 2010 Iowa State University

Impacts Of Individual Tree Species On Carbon Dynamics In A Moist Tropical Forest Environment, Ann E. Russell, James W. Raich, Ricardo Bedoya Arrieta, Oscar Valverde-Barrantes, Eugenio González

Natural Resource Ecology and Management Publications

In the moist tropical forest biome, which cycles carbon (C) rapidly and stores huge amounts of C, the impacts of individual species on C balances are not well known. In one of the earliest replicated experimental sites for investigating growth of native tropical trees, we examined traits of tree species in relation to their effects on forest C balances, mechanisms of influence, and consequences for C sequestration. The monodominant stands, established in abandoned pasture in 1988 at La Selva Biological Station, Costa Rica, contained five species in a complete randomized block design. Native species were: Hieronyma alchorneoides, Pentaclethra macroloba, Virola ...


Outcomes Of A One-Week Teaching Training In Community-Based Ecological Research, Kara Gonsler 2010 Portland State University

Outcomes Of A One-Week Teaching Training In Community-Based Ecological Research, Kara Gonsler

Master of Environmental Management Project Reports

The goal of this project was to expand on potential audiences and partnerships within the Teaching Ecological Complexity Project, by creating a one-week teacher training workshop in collaboration with a local natural resource management partner. The training sought to increase teachers’ understanding of ecology and qualitative conceptual models through immersion in field research and partnerships with local scientists and natural resource managers. Ecological knowledge was measured by comparing pre and post qualitative conceptual models, which were scored with a rubric and analyzed using the Wilcoxon Signed Ranks Test. Classroom implementation of an inquiry-based ecological research project was expected of participants ...


Modeling The Effect Of Oceanic Internal Waves On The Accuracy Of Multibeam Echosounders, Travis Hamilton, Jonathan Beaudoin 2010 University of New Brunswick

Modeling The Effect Of Oceanic Internal Waves On The Accuracy Of Multibeam Echosounders, Travis Hamilton, Jonathan Beaudoin

Center for Coastal and Ocean Mapping

When ray bending corrections are applied to multibeam echosounder (MBES) data, it is assumed that the varying layers of sound speed lie along horizontally stratified planes. In many areas internal waves occur at the interface where the water’s density changes abruptly (a pycnocline), this density gradient is often associated with a strong gradient in sound speed (a velocline). The internal wave introduces uncertainty into the echo soundings through two mechanisms: (1) tilting of the velocline, and (2) vertical oscillation of the velocline’s depth. A model has been constructed in order to examine how these effects degrade the accuracy ...


On Trustworthiness Of Cpu Usage Metering And Accounting, Mei LIU, Xuhua DING 2010 Singapore Management University

On Trustworthiness Of Cpu Usage Metering And Accounting, Mei Liu, Xuhua Ding

Research Collection School Of Information Systems

In the envisaged utility computing paradigm, a user taps a service provider’s computing resources to accomplish her tasks, without deploying the needed hardware and software in her own IT infrastructure. To make the service profitable, the service provider charges the user based on the resources consumed. A commonly billed resource is CPU usage. A key factor to ensure the success of such a business model is the trustworthiness of the resource metering scheme. In this paper, we provide a systematic study on the trustworthiness of CPU usage metering. Our results show that the metering schemes in commodity operating systems ...


Stevent: Spatio-Temporal Event Model For Social Network Discovery, Hady W. LAUW, Ee Peng LIM, Hwee Hwa PANG, Teck-Tim TAN 2010 Singapore Management University

Stevent: Spatio-Temporal Event Model For Social Network Discovery, Hady W. Lauw, Ee Peng Lim, Hwee Hwa Pang, Teck-Tim Tan

Research Collection School Of Information Systems

Spatio-temporal data concerning the movement of individuals over space and time contains latent information on the associations among these individuals. Sources of spatio-temporal data include usage logs of mobile and Internet technologies. This article defines a spatio-temporal event by the co-occurrences among individuals that indicate potential associations among them. Each spatio-temporal event is assigned a weight based on the precision and uniqueness of the event. By aggregating the weights of events relating two individuals, we can determine the strength of association between them. We conduct extensive experimentation to investigate both the efficacy of the proposed model as well as the ...


Efficient Processing Of Exact Top-K Queries Over Disk-Resident Sorted Lists, Hwee Hwa PANG, Xuhua DING, Baihua ZHENG 2010 Singapore Management University

Efficient Processing Of Exact Top-K Queries Over Disk-Resident Sorted Lists, Hwee Hwa Pang, Xuhua Ding, Baihua Zheng

Research Collection School Of Information Systems

The top-k query is employed in a wide range of applications to generate a ranked list of data that have the highest aggregate scores over certain attributes. As the pool of attributes for selection by individual queries may be large, the data are indexed with per-attribute sorted lists, and a threshold algorithm (TA) is applied on the lists involved in each query. The TA executes in two phases--find a cut-off threshold for the top-k result scores, then evaluate all the records that could score above the threshold. In this paper, we focus on exact top-k queries that involve monotonic linear ...


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