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Copula And Default Correlation, Dongxiang Yan 2010 Louisiana State University and Agricultural and Mechanical College

Copula And Default Correlation, Dongxiang Yan

LSU Master's Theses

This work presents a study of copulas, with special focus on the Gaussian copula model and its behavior under a certain conditioning process. Simulations are carried out to examine the behavior of the moments on conditional copula model, as measured by the behavior of Wick identities which hold for multivariate Gaussians.


Wetland Program Plan For Nebraska, Ted LaGrange 2010 Nebraska Game and Parks Commission

Wetland Program Plan For Nebraska, Ted Lagrange

Nebraska Game and Parks Commission -- White Papers, Conference Presentations, & Manuscripts

The State of Nebraska plans to continue to implement its wetland program over the next three calendar years (2011-2013). In 2011, Nebraska will undertake an intensification study to assess the condition of its wetlands in 10 different wetland complexes. The State will use this information to improve our understanding of baseline wetland conditions, and to prioritize wetland restoration and protection activities. Nebraska will continue to work in partnership with landowners, agencies, and organizations to restore and protect 9,000 acres of wetlands. The priorities for the restoration and protection will be determined by the Nebraska Game and Parks Commission and ...


Misalignment Induced Nodal Aberration Fields And Their Use In The Alignment Of Astronomical Telescopes, Tobias Schmid 2010 University of Central Florida

Misalignment Induced Nodal Aberration Fields And Their Use In The Alignment Of Astronomical Telescopes, Tobias Schmid

Electronic Theses and Dissertations

Following the foundation of aberration theory for rotationally symmetric optical systems established by Seidel, Schwarzschild, Burch, Conrady, Buchdahl, and in its most useful form H.H. Hopkins, Shack, Buchroeder, Thompson, and Rogers developed a vectorial form of the wave aberration theory that enables addressing optical systems without symmetry. In this research, a vectorial theory is utilized and extended for the alignment of two- and three-mirror astronomical telescopes, including the effects of pointing changes and astigmatic figure errors. Importantly, it is demonstrated that the vectorial form of aberration theory, also referred to as nodal aberration theory, not only provides valuable insights ...


A New Framework For Qos Provisioning In Wireless Lans Using The P-Persistent Mac Protocol, Kiran Babu Anna 2010 University of Central Florida

A New Framework For Qos Provisioning In Wireless Lans Using The P-Persistent Mac Protocol, Kiran Babu Anna

Electronic Theses and Dissertations

The support of multimedia traffic over IEEE 802.11 wireless local area networks (WLANs) has recently received considerable attention. This dissertation has proposed a new framework that provides efficient channel access, service differentiation and statistical QoS guarantees in the enhanced distributed channel access (EDCA) protocol of IEEE 802.11e. In the first part of the dissertation, the new framework to provide QoS support in IEEE 802.11e is presented. The framework uses three independent components, namely, a core MAC layer, a scheduler, and an admission control. The core MAC layer concentrates on the channel access mechanism to improve the overall ...


Architectural Support For Improving Computer Security, Jingfei Kong 2010 University of Central Florida

Architectural Support For Improving Computer Security, Jingfei Kong

Electronic Theses and Dissertations

Computer security and privacy are becoming extremely important nowadays. The task of protecting computer systems from malicious attacks and potential subsequent catastrophic losses is, however, challenged by the ever increasing complexity and size of modern hardware and software design. We propose several methods to improve computer security and privacy from architectural point of view. They provide strong protection as well as performance efficiency. In our first approach, we propose a new dynamic information flow method to protect systems from popular software attacks such as buffer overflow and format string attacks. In our second approach, we propose to deploy encryption schemes ...


Simulation Of Photochromic Compounds Using Density Functional Theory Methods, Pansy Patel 2010 University of Central Florida

Simulation Of Photochromic Compounds Using Density Functional Theory Methods, Pansy Patel

Electronic Theses and Dissertations

This Thesis describes the systematic theoretical study aimed at prediction of the essential properties for the functional organic molecules that belong to diarylethene (DA) family of compounds. Diarylethenes present the distinct ability to change color under the influence of light, known as photochromism. This change is due to ultrafast chemical transition from open to closed ring isomers (photocyclization). It can be used for optical data storage, photoswitching, and other photonic applications. In this work we apply Density Functional Theory methods to predict 6 of the related properties: (i) molecular geometry; (ii) resonant wavelength; (iii) thermal stability; (iv) fatigue resistance; (v ...


Toward A Whole-Landscape Approach For Sustainable Land Use In The Tropics, R. DeFries, C. Rosenzweig 2010 Columbia University

Toward A Whole-Landscape Approach For Sustainable Land Use In The Tropics, R. Defries, C. Rosenzweig

NASA Publications

Increasing food production and mitigating climate change are two primary but seemingly contradictory objectives for tropical landscapes. This special feature examines synergies and trade-offs among these objectives. Four themes emerge from the papers: the important roles of both forest and agriculture sectors for climate mitigation in tropical countries; the minor contribution from deforestation-related agricultural expansion to overall food production at global and continental scales; the opportunities for synergies between improved food production and reductions in greenhouse gas emissions through diversion of agricultural expansion to already-cleared lands, improved soil, crop, and livestock management, and agroforestry; and the need for targeted policy ...


Development And Evaluation Of A Cloud-Gap-Filled Modis Daily Snow-Cover Product, Dorothy K. Hall, George A. Riggs, James L. Foster, Sujay V. Kumar 2010 NASA Goddard Space Flight Center

Development And Evaluation Of A Cloud-Gap-Filled Modis Daily Snow-Cover Product, Dorothy K. Hall, George A. Riggs, James L. Foster, Sujay V. Kumar

NASA Publications

The utility of the Moderate Resolution Imaging Spectroradiometer (MODIS) snow-cover products is limited by cloud cover which causes gaps in the daily snow-cover map products. Wedescribe a cloud-gap-filled (CGF) daily snow-covermap using a simple algorithmto track cloud persistence, to account for the uncertainty created by the age of the snow observation. Developed from the 0.05° resolution climate-modeling grid daily snow-cover product,MOD10C1, each grid cell of the CGFmap provides a cloud-persistence count (CPC) that tellswhether the current or a prior day was used to make the snow decision. Percentage of grid cells “observable” is shown to increase dramatically when ...


Automation For Task Analysis Of Next Generation Air Traffic Management Systems, Maricel Medina, Lance Sherry, Michael Feary 2010 George Mason University

Automation For Task Analysis Of Next Generation Air Traffic Management Systems, Maricel Medina, Lance Sherry, Michael Feary

NASA Publications

The increasing span of control of Air Traffic Control enterprise automation (e.g. Flight Schedule Monitor, Departure Flow Management), along with lean-processes and pay-for-performance business models, has placed increased emphasis on operator training time and error rates. There are two traditional approaches to the design of human–computer interaction (HCI) to minimize training time and reduce error rates: (1) experimental user testing provides the most accurate assessment of training time and error rates, but occurs too late in the development cycle and is cost prohibitive, (2) manual review methods (e.g. cognitive walk through) can be used earlier in the ...


Remote Sensing Of Phytoplankton Pigment Distribution In The United States Northeast Coast, Xiaoju Pan, Antonio Mannino, Mary E. Russ, Stanford B. Hooker, Lawrence Harding 2010 NASA Goddard Space Flight Center

Remote Sensing Of Phytoplankton Pigment Distribution In The United States Northeast Coast, Xiaoju Pan, Antonio Mannino, Mary E. Russ, Stanford B. Hooker, Lawrence Harding

NASA Publications

Phytoplankton pigments constitute many more compounds than chlorophyll a that can be applied to study phytoplankton diversity, populations, and primary production. In this study, field measurements were applied to develop ocean color satellite algorithms of phytoplankton pigments from in-water radiometry measurements. The match-up comparisons showed that the satellite-derived pigments from our algorithms agree reasonably well (e.g. 30–55% of uncertainty for SeaWiFS and 37–50% for MODIS-Aqua) to field data, with better agreement (e.g. 30–38% of uncertainty for SeaWiFS and 39–44% for MODIS-Aqua) for pigments abundant in diatoms. The seasonal and spatial variations of satellite-derived phytoplankton ...


The Carbon Budget Of California, Christopher Potter 2010 NASA Ames Research Center

The Carbon Budget Of California, Christopher Potter

NASA Publications

The carbon budget of a region can be defined as the sum of annual fluxes of carbon dioxide (CO2) and methane (CH4) greenhouse gases (GHGs) into and out of the regional surface coverage area. According to the state government’s recent inventory, California’s carbon budget is presently dominated by 115 MMTCE per year in fossil fuel emissions of CO2 (>85% of total annual GHG emissions) to meet energy and transportation requirements. Other notable (non-ecosystem) sources of carbon GHG emissions in 2004 were from cement- and lime-making industries (7%), livestock-based agriculture (5%), and waste treatment activities (2 ...


Test Method Variability In Slow Crack Growth Properties Of Sealing Glasses, J. Salem, R. Tandon 2010 NASA Glenn Research Center

Test Method Variability In Slow Crack Growth Properties Of Sealing Glasses, J. Salem, R. Tandon

NASA Publications

The crack growth properties of several sealing glasses were measured by using constant stress rate testing in ~2% and 95% RH (relative humidity). Crack growth parameters measured in high humidity are systematically smaller (n and B) than those measured in low humidity, and crack velocities for dry environments are ~100 x lower than for wet environments. The crack velocity is very sensitivity to small changes in RH at low RH. Biaxial and uniaxial stress states produced similar parameters. Confidence intervals on crack growth parameters that were estimated from propagation of errors solutions were comparable to those from Monte Carlo simulation ...


Evaluation Of Shortwave Infrared Atmospheric Correction For Ocean Color Remote Sensing Of Chesapeake Bay, P. Jeremy Werdell, Bryan A. Franz, Sean W. Bailey 2010 NASA Goddard Space Flight Center

Evaluation Of Shortwave Infrared Atmospheric Correction For Ocean Color Remote Sensing Of Chesapeake Bay, P. Jeremy Werdell, Bryan A. Franz, Sean W. Bailey

NASA Publications

The NASA Moderate Resolution Imaging Spectroradiometer onboard the Aqua platform (MODIS-Aqua) provides a viable data stream for operational water quality monitoring of Chesapeake Bay. Marine geophysical products from MODIS-Aqua depend on the efficacy of the atmospheric correction process, which can be problematic in coastal environments. The operational atmospheric correction algorithm for MODISAqua requires an assumption of negligible near-infrared water-leaving radiance, nLw(NIR). This assumption progressively degrades with increasing turbidity and, as such, methods exist to account for non-negligible nLw(NIR) within the atmospheric correction process or to use alternate radiometric bands where the assumption is satisfied, such as ...


Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley 2010 California State Polytechnic University

Identifying A Computer Forensics Expert: A Study To Measure The Characteristics Of Forensic Computer Examiners, Gregory H. Carlton, Reginald Worthley

Journal of Digital Forensics, Security and Law

The usage of digital evidence from electronic devices has been rapidly expanding within litigation, and along with this increased usage, the reliance upon forensic computer examiners to acquire, analyze, and report upon this evidence is also rapidly growing. This growing demand for forensic computer examiners raises questions concerning the selection of individuals qualified to perform this work. While courts have mechanisms for qualifying witnesses that provide testimony based on scientific data, such as digital data, the qualifying criteria covers a wide variety of characteristics including, education, experience, training, professional certifications, or other special skills. In this study, we compare task ...


Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz 2010 AGH University of Science and Technology

Adaptation Of Pyflag To Efficient Analysis Of Seized Computer Data Storage, Aleksander Byrski, Wojciech Stryjewski, Bartłomiej Czechowicz

Journal of Digital Forensics, Security and Law

Based on existing software aimed at investigation support in the analysis of computer data storage seized during investigation (PyFlag), an extension is proposed involving the introduction of dedicated components for data identification and filtering. Hash codes for popular software contained in NIST/NSRL database are considered in order to avoid unwanted files while searching and to classify them into several categories. The extension allows for further analysis, e.g. using artificial intelligence methods. The considerations are illustrated by the overview of the system's design.


Table Of Contents, 2010 Embry-Riddle Aeronautical University

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.


Computer Forensic Functions Testing: Media Preparation, Write Protection And Verification, Yinghua Guo, Jill Slay 2010 University of South Australia

Computer Forensic Functions Testing: Media Preparation, Write Protection And Verification, Yinghua Guo, Jill Slay

Journal of Digital Forensics, Security and Law

The growth in the computer forensic field has created a demand for new software (or increased functionality to existing software) and a means to verify that this software is truly forensic i.e. capable of meeting the requirements of the trier of fact. In this work, we review our previous work---a function oriented testing framework for validation and verification of computer forensic tools. This framework consists of three parts: function mapping, requirements specification and reference set development. Through function mapping, we give a scientific and systemized description of the fundamentals of computer forensic discipline, i.e. what functions are needed ...


Digital Records Forensics: A New Science And Academic Program For Forensic Readiness, Luciana Duranti, Barbara Endicott-Popovsky 2010 The University of British Columbia

Digital Records Forensics: A New Science And Academic Program For Forensic Readiness, Luciana Duranti, Barbara Endicott-Popovsky

Journal of Digital Forensics, Security and Law

This paper introduces the Digital Records Forensics project, a research endeavour located at the University of British Columbia in Canada and aimed at the development of a new science resulting from the integration of digital forensics with diplomatics, archival science, information science and the law of evidence, and of an interdisciplinary graduate degree program, called Digital Records Forensics Studies, directed to professionals working for law enforcement agencies, legal firms, courts, and all kind of institutions and business that require their services. The program anticipates the need for organizations to become “forensically ready,” defined by John Tan as “maximizing the ability ...


Book Review: Digital Forensic Evidence Examination (2nd Ed.), Gary C. Kessler 2010 Gary Kessler Associates

Book Review: Digital Forensic Evidence Examination (2nd Ed.), Gary C. Kessler

Journal of Digital Forensics, Security and Law

On the day that I sat down to start to write this review, the following e-mail came across on one of my lists: Person A and Person B write back and forth and create an email thread. Person A then forwards the email to Person C, but changes some wording in the email exchange between A & B. What is the easiest way (and is it even possible) to find out when that earlier email message was altered before sent to Person C? Before you try to answer these questions, read Fred Cohen's Digital Forensic Evidence Examination. His book won ...


Table Of Contents, 2010 Embry-Riddle Aeronautical University

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.


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