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Articles 24601 - 24630 of 27887
Full-Text Articles in Physical Sciences and Mathematics
Natural Resource Management Newsletter, Fall 2020/Winter 2021, Department Of Natural Resource Management
Natural Resource Management Newsletter, Fall 2020/Winter 2021, Department Of Natural Resource Management
NRM Newsletter
[Page] 2 One Day for State
[Page] 2 SDSU Extension NPI Range Roundup
[Page] 3 Con McCrea and NRLE News
[Page] 3 Pete Bauman Updates Western SD Undisturbed Land Data
[Page] 4 First Annual NPI Photo Contest
[Page] 4 Conservation Planning & Park Management Undergraduate Student Eagle Scout Project
[Page] 5 Joe Jenks' Zoom Retirement Celebration
[Page] 6 NRM Affiliate Assistant Professor, Maaz Gardezi - NSF Precision Ag Project: NSF project to build farmers’ confidence in precision ag technologies
[Page] 6 NRM Affiliate, Stella Liu - Faculty Feature video
[Page] 7 SDSU Extension to assess farm-ranch stress statewide
[Page] 8 …
Cyber Insurance Effects On Cyber Hygiene: Does The Homeostatic Effect Apply?, Wendi M. Kappers, Aaron Glassman, Michael S. Wills
Cyber Insurance Effects On Cyber Hygiene: Does The Homeostatic Effect Apply?, Wendi M. Kappers, Aaron Glassman, Michael S. Wills
Publications
A theoretical framework and research strategy is proposed to gain insight into perceptions and decisions as to how SMBs make decisions regarding cybersecurity hygiene measures, which could lead to betterinformed decisions regarding insurance as part of an ISA program, as well as have a bearing on policy structures and pricing for such insurance. This is because the definition of “cybersecurity hygiene habits”(CHH) as a task appears to vary within the industry and makes the practice hard to measure and evaluate. Research suggests that there may be a poorly understood connection between CHHs undertaken by organizations and their perceptions and/or adoption …
Detection Of 2,4,6-Trinitrotoluene Using A Colorimetric Gold Nanoparticle Air Cassette Filter, Andrea I. Ferrer Vega
Detection Of 2,4,6-Trinitrotoluene Using A Colorimetric Gold Nanoparticle Air Cassette Filter, Andrea I. Ferrer Vega
Theses and Dissertations
Trinitrotoluene (TNT) is an explosive commonly used during military and terrorist activities. Current methods to identify this compound require sampling, transport and analysis at a forensic lab using analytical instrumentation. However, on-site detection is needed to assist efforts to prevent detonation. Gold nanoparticles have been used as sensors throughout the years due to their versatility and surface enhanced Raman scattering properties in the presence of an analyte and low limits of detection. By taking advantage of the Meisenheimer complex that TNT forms in the presence of amines, it is possible to determine its presence at picogram levels. Subsequently, adhering amine …
Evaluation Of Five Methods To Develop Latent Prints On Thermal Paper, Jenna Pregent
Evaluation Of Five Methods To Develop Latent Prints On Thermal Paper, Jenna Pregent
Theses and Dissertations
Forensic latent fingerprint laboratories determine the proper techniques for fingerprint visualization based on the substrates upon which they are deposited. Typical forensic analysis of thermal paper evidence involves the application of ninhydrin and/or 1,2-indanedione dissolved in a polar solvent. However, polar solvents create an undesirable reaction with the thermal paper’s internal properties and often lead to discoloration of the evidence. When this occurs, not only are the fingerprints less likely to be visible due to the loss of contrast, but the evidentiary print on the receipt may be lost entirely. This research sought to compare five development methods to determine …
Causal Mediation Analysis For Difference-In-Difference Design And Panel Data, Pei-Hsuan Hsia, An-Shun Tai, Chu-Lan Michael Kao, Yu-Hsuan Lin, Sheng-Hsuan Lin
Causal Mediation Analysis For Difference-In-Difference Design And Panel Data, Pei-Hsuan Hsia, An-Shun Tai, Chu-Lan Michael Kao, Yu-Hsuan Lin, Sheng-Hsuan Lin
Harvard University Biostatistics Working Paper Series
Advantages of panel data, i.e., difference in difference (DID) design data, are a large sample size and easy availability. Therefore, panel data are widely used in epidemiology and in all social science fields. The literatures on causal inferences of panel data setting or DID design are growing, but no theory or mediation analysis method has been proposed for such settings. In this study, we propose a methodology for conducting causal mediation analysis in DID design and panel data setting. We provide formal counterfactual definitions for controlled direct effect and natural direct and indirect effect in panel data setting and DID …
Salish Sea Circulation Diagram, Aquila Flower
Salish Sea Circulation Diagram, Aquila Flower
Salish Sea Maps
. Direction and relative magnitude (line width) of net water flow in the Salish Sea. Deep water flows represent primarily marine waters entering the Salish Sea from the Pacific Ocean. Intermediate depth and surface flows represent a mix of marine waters and freshwater from rivers in the Salish Sea. Actual circulation patterns are highly complex and seasonally variable, this diagram shows a simplified model of net exchanges. Labels indicate percent of the total water exchange that moves in and out of the Salish Sea through the Strait of Juan de Fuca in the south and through the northern boundary of …
Salish Sea Stream Discharge Diagram, Aquila Flower
Salish Sea Stream Discharge Diagram, Aquila Flower
Salish Sea Maps
Major rivers of the Salish Sea and average stream discharge (cubic meters per second). Data are based on annual averages from 1981 to 2010.
Figure 2.3 in the
Salish Sea Bioregion Reference Map, Aquila Flower
Salish Sea Bioregion Reference Map, Aquila Flower
Salish Sea Maps
Map of the Salish Sea, major waterways, and surrounding watersheds, which when combined form a distinct transboundary bioregion.
Figure 1.1 in the
Salish Sea Population Density, Aquila Flower
Salish Sea Population Density, Aquila Flower
Salish Sea Maps
Human population density in the Salish Sea. People per square kilometer mapped for each census block. Data from 2010 in the US and 2011 in Canada.
Figure 3.1 in the
Salish Sea Jurisdictions, Aquila Flower
Salish Sea Jurisdictions, Aquila Flower
Salish Sea Maps
US Counties, Canadian Regional Districts, and major cities in the Salish Sea Bioregion.
Figure 1.3 in the
Marine Basins, Aquila Flower
Marine Basins, Aquila Flower
Salish Sea Maps
Subbasins and bathymetry of the Salish Sea. Basins are delineated based on water depth and circulation. Shallower areas associated with underwater sills separate many of the basins, creating distinct oceanography.
Figure 2.5 in the
Salish Sea Land Cover, Aquila Flower
Salish Sea Land Cover, Aquila Flower
Salish Sea Maps
Land cover in the Salish Sea bioregion. Land cover categories modeled using 30x30 meter resolution gridded satellite data from 2015.
Figure 3.2 in the
Salish Sea And Western North America Watersheds Contextual Landscape, Aquila Flower
Salish Sea And Western North America Watersheds Contextual Landscape, Aquila Flower
Salish Sea Maps
No abstract provided.
Spectra Of Weighted Composition Operators With Quadratic Symbols, Derek Thompson, Jessica Doctor, Timothy Hodges, Alexander Mcfarland, Scott Kaschner
Spectra Of Weighted Composition Operators With Quadratic Symbols, Derek Thompson, Jessica Doctor, Timothy Hodges, Alexander Mcfarland, Scott Kaschner
Mathematics Student Projects
Previously, spectra of certain weighted composition operators on the Hardy space were determined under one of two hypotheses: either the compositional symbol converges under iteration to the Denjoy-Wolff point uniformly on the entire open unit disk rather than simply on compact subsets, or it is “essentially linear fractional.” We show that if the compositional symbol is a quadratic self-map of the open disk of parabolic type, then the spectrum of associated weighted composition operators can be found when these maps exhibit both of the aforementioned properties, and we determine which symbols do so.
How To Estimate Time Needed For Software Migration, Francisco Zapata, Olga Kosheleva, Vladik Kreinovich
How To Estimate Time Needed For Software Migration, Francisco Zapata, Olga Kosheleva, Vladik Kreinovich
Departmental Technical Reports (CS)
In many practical situations, we need to migrate the existing software package to a new programming language and/or a new operating system. In such a migration, it is important to be able to accurately estimate time needed for this migration: if we underestimate this time, we will lose money and may go bankrupt; if we overestimate this time, other companies who estimate more accuracy will outbid us, and we will lose the contract. The formulas currently used for estimating migration time often lead to underestimation. In this paper, we start with the main ideas behind the existing formulas, and show …
Distributions On An Interval As A Scale-Invariant Combination Of Scale-Invariant Functions: Theoretical Explanation Of Empirical Marchenko-Pastur-Type Distributions, Vladik Kreinovich, Kevin Alvarez, Chon Van Le
Distributions On An Interval As A Scale-Invariant Combination Of Scale-Invariant Functions: Theoretical Explanation Of Empirical Marchenko-Pastur-Type Distributions, Vladik Kreinovich, Kevin Alvarez, Chon Van Le
Departmental Technical Reports (CS)
In many practical situations, we know the lower and upper bounds L and U on possible values of a quantity x. In such situations, the probability distribution of this quantity is also located on the corresponding interval [L, U]. In many such cases, the empirical probability distribution has the form d(x) = const * (x − L)α− * (U − x)α+ * xα. In the particular case α− = α+ = 0.5 and α = −1, we get the Marchenko-Pastur distribution that describes the distribution of the eigenvalues of a random matrix. However, in some cases, the empirical distribution corresponds …
How To Guarantee Fairness Of Grading Without Sacrificing Privacy?, Vladik Kreinovich, Olga Kosheleva, Christian Servin
How To Guarantee Fairness Of Grading Without Sacrificing Privacy?, Vladik Kreinovich, Olga Kosheleva, Christian Servin
Departmental Technical Reports (CS)
Everyone -– instructors and students –- want to make sure that grading of each test is fair, that the only thing that determines the students’ grade is their level of knowledge, that different students get the same penalty for the same mistake, irrespective of their gender, of their past grades, of their behavior in the class, of how many classes they missed, etc. How to help instructors achieve this goal? How to make sure that students are convinced that grading was indeed fair? In this paper, we describe possible measures: anonymous submissions, forming (and posting for all the student to …
Can Ideas Behind Ancient Egyptian Fractions Speed Up Modern Computers?, Olga Kosheleva, Vladik Kreinovich
Can Ideas Behind Ancient Egyptian Fractions Speed Up Modern Computers?, Olga Kosheleva, Vladik Kreinovich
Departmental Technical Reports (CS)
To divide two numbers a and b, modern computers use an algorithm which is more efficient that what we humans normally do: they compute a*(1/b), where for all sufficiently small integers b, the inverse 1/b is pre-computed. For fractions, when both a and b are integers, this algorithm requires only one multiplication. Can we make the procedure even faster by not using multiplication at all? To do this, we need to represent each fraction as the sum of inverses -- which, interestingly, is how ancient Egyptians represented fractions.
Tents Of Israel Revisited: Audio Privacy, Julio C. Urenda, Olga Kosheleva, Vladik Kreinovich
Tents Of Israel Revisited: Audio Privacy, Julio C. Urenda, Olga Kosheleva, Vladik Kreinovich
Departmental Technical Reports (CS)
In one of the Biblical stories, prophet Balaam blesses the tents of Israel for being good. But what can be so good about the tents? The traditional Rabbinical interpretation is that the placement of the tents provided full privacy. In our previous paper, we considered the consequences of visual privacy: from each entrance, one cannot see what is happening at any other entrance. In this paper, we analyze the possible consequences of audio privacy: from each tent, you cannot hear what is going on in other tents.
Fireeye: Cybersecurity In Action, Singapore Management University
Fireeye: Cybersecurity In Action, Singapore Management University
Perspectives@SMU
FireEye built its success on its ‘Human + AI’ philosophy. But can a cybersecurity firm get ahead of the attackers and predict an attack…on itself?
A New Extended Alpha Power Transformed Family Of Distributions: Properties, Characterizations And An Application To A Data Set In The Insurance Sciences, Zubair Ahmad, Eisa Mahmoudi, Gholamhossein Hamedani
A New Extended Alpha Power Transformed Family Of Distributions: Properties, Characterizations And An Application To A Data Set In The Insurance Sciences, Zubair Ahmad, Eisa Mahmoudi, Gholamhossein Hamedani
Mathematical and Statistical Science Faculty Research and Publications
Heavy tailed distributions are useful for modeling actuarial and financial risk management problems. Actuaries often search for finding distributions that provide the best fit to heavy tailed data sets. In the present work, we introduce a new class of heavy tailed distributions of a special sub-model of the proposed family, called a new extended alpha power transformed Weibull distribution, useful for modeling heavy tailed data sets. Mathematical properties along with certain characterizations of the proposed distribution are presented. Maximum likelihood estimates of the model parameters are obtained. A simulation study is provided to evaluate the performance of the maximum likelihood …
Experimental Exploration Of Shared Magnetic Phases Between Diverse Systems Of Iron-Pnictide Superconductors, Ryan Scott Stadel
Experimental Exploration Of Shared Magnetic Phases Between Diverse Systems Of Iron-Pnictide Superconductors, Ryan Scott Stadel
Graduate Research Theses & Dissertations
The exciting field of iron-pnictide superconductors offers unique opportunities for studying the relationship between magnetism and unconventional superconductivity. This is vital to developing an understanding of the microscopic origin of high-temperature superconductivity, which is itself an important step in harnessing such a potentially revolutionary technology.
Polycrystalline and crystalline samples are synthesized over a diverse collection of related iron-pnictide systems including (Ca,Sr,Ba)1-xNaxFe2As2, Ba(Fe1-xCox)2As2 (122s), and LaFeAs1-xPxO, and TbFeAs1-xPxO (1111s). These compounds are characterized through various types of neutron and x-ray diffraction on multiple instruments, as well as muon spin resonance, and magnetic susceptibility measurements.
A thorough investigation into the conditions under …
Synthesis And Functionality Study Of Novel Biomimetic N-Glycan Polymers, Ka Keung Chan
Synthesis And Functionality Study Of Novel Biomimetic N-Glycan Polymers, Ka Keung Chan
ETD Archive
Cell surface carbohydrates, existing as glycoproteins, glycolipids, and proteoglycans, often serve as receptors to relay critical interactions and trigger crucial signaling events in many biological processes. Glycan recognition is deeply involved in immune surveillance, response and can provide abundant opportunities to discover the molecular mechanism and potential therapeutic or diagnostic approaches for various diseases. Many useful functionalities can be achieved by developing synthetic glycans to mimic natural carbohydrates. Over the recent decade, glycopolymers, polymers with pendant carbohydrates, have continued to prove usefulness in various applications across different scientific disciplines. For example, glycopolymers can be used as biomimetic glycoligands to study …
Synthesis, Characterization, And Catalytic And Biological Activities Of A Mixed-Ligand Cobalt(Ii) Bipyridyl/Diphenylazodioxide Complex, Kylin A. Emhoff
Synthesis, Characterization, And Catalytic And Biological Activities Of A Mixed-Ligand Cobalt(Ii) Bipyridyl/Diphenylazodioxide Complex, Kylin A. Emhoff
ETD Archive
Transition metal complexes have immense importance in the pharmaceutical industry. These types of complexes can be useful catalysts in the synthesis of medicinal compounds and can act as anticancer drugs. In these pharmaceutical applications, 1st-row transition metal-containing complexes offer certain advantages compared to their 2nd and 3rd-row transition metal counterparts. Our motivation was to investigate pharmaceutical applications of transition metal complexes containing both a 1st-row transition metal and unusual ligands to expand the knowledge of a class of complexes that could potentially be beneficial in the pharmaceutical industry. A class of rare ligands that piqued our interest was that of …
Existing Competencies In The Teaching Of Ethics In Computer Science Faculties, Ethics4eu Consortium
Existing Competencies In The Teaching Of Ethics In Computer Science Faculties, Ethics4eu Consortium
Reports
This report is one of the deliverables for the Ethics4EU project. It presents results obtained from a survey conducted in early 2020 that polled faculty from Computer Science and related disciplines on teaching practices in Computer Ethics in Computer Science across Europe. The survey was completed by respondents from 61 universities across 23 European countries. Participants were surveyed on whether or not Computer Ethics is taught to Computer Science students at each institution, the reasons why Computer Ethics is or is not taught, how Computer Ethics is taught (for example, as a standalone course or embedded within other courses), the …
Online Versus In-Person Mathematics Instruction: A Comparison Of Two Instructional Models, Chelsea J. Fisher, Catherine Henney, Patrick Marcolini, Allison Yoder
Online Versus In-Person Mathematics Instruction: A Comparison Of Two Instructional Models, Chelsea J. Fisher, Catherine Henney, Patrick Marcolini, Allison Yoder
Journal of Mathematics and Science: Collaborative Explorations
Our paper explores the differences between online and traditional, in-person teaching and learning modalities, looking specifically at courses preparing teachers to be mathematics teacher leaders. In the context of current research on the teaching and learning of mathematics in an online setting, we share our own experiences. We describe the preparation for and teaching of online mathematics, focusing on establishing norms and the use of technology. The changing teaching and learning opportunities of the 21st century require discussion of these vital issues. We include stories of interactions between candidates and teachers and among groups of candidates in mathematics courses, detailing …
Learning To Anticipate In An Online Class: Perspectives Of An Instructor And A Mathematics Specialist Candidate, Kristina C. Anthony, Melody O'Quinn
Learning To Anticipate In An Online Class: Perspectives Of An Instructor And A Mathematics Specialist Candidate, Kristina C. Anthony, Melody O'Quinn
Journal of Mathematics and Science: Collaborative Explorations
This paper will highlight two perspectives, a course instructor and a mathematics specialist candidate working together in an online course, on the practice of anticipating how a learner will approach a task or assignment. The candidate shares her experiences in developing an understanding of what it means to anticipate student responses and implement mathematical practice in the classroom. She also shares how learning to anticipate has impacted her teaching. The instructor reflects on her experiences (or lack thereof) in anticipating how students would engage in the online environment. From the instructor and the candidate perspectives, learning to anticipate helped to …
Developing Equity-Centered Leadership Knowledge And Skills Via Lesson Study In An Online Mathematics Specialist Program, Courtney K. Baker, Spencer Jamieson, Adrienne Paul, Scarlett Kibler, Alyson Eaglen, Tammy Kraft
Developing Equity-Centered Leadership Knowledge And Skills Via Lesson Study In An Online Mathematics Specialist Program, Courtney K. Baker, Spencer Jamieson, Adrienne Paul, Scarlett Kibler, Alyson Eaglen, Tammy Kraft
Journal of Mathematics and Science: Collaborative Explorations
This paper highlights how coursework within a synchronous online mathematics specialist program enhanced candidates’ leadership knowledge and provided structures that addressed issues of equity and access. A focus on one online assignment grounded in Lesson Study played a pivotal role in developing equity-centered leadership and instructional practices. Program instructors and recent alumni illuminate how designing, implementing, and reflecting on the Lesson Study experience served as a cornerstone for advancing their mathematics instruction in the following ways: (a) as instructors designing an online leadership course, (b) as learners within an online environment, and (c) as educators within their K–8 school settings. …
Transcriptional Repressor Protein Based Macrolide Biosensor Development With Improved Sensitivity, Jayani A. Christopher
Transcriptional Repressor Protein Based Macrolide Biosensor Development With Improved Sensitivity, Jayani A. Christopher
Graduate Research Posters
Macrolide antibiotics are in high demand for clinical applications. Macrolides are biosynthesized via giant assembly line polyketide synthases (PKS) which are arranged in a modular fashion. Combinatorial biosynthetic methods have been used to produce diversified macrolides by reprograming these modules and modifying tailoring enzymes required for post synthetic modifications. However it is challenging due to the size and complexity of PKSs. To overcome this challenge, new enzymes for macrolide diversification could be obtained by directed evolution where a large number of enzyme variants need to be screened. Therefore it is important to develop high throughput screening methods to identify the …
Principal Components Analysis Corrects Collider Bias In Polygenic Risk Score Effect Size Estimation, Nathaniel S. Thomas, Peter B. Barr, Fazil Aliev, Sally I. Kuo, Danielle M. Dick, Jessica E. Salvatore
Principal Components Analysis Corrects Collider Bias In Polygenic Risk Score Effect Size Estimation, Nathaniel S. Thomas, Peter B. Barr, Fazil Aliev, Sally I. Kuo, Danielle M. Dick, Jessica E. Salvatore
Graduate Research Posters
BACKGROUND: Genome-wide polygenic scoring has emerged as a way to predict psychiatric and behavioral outcomes and identify environments that promote the expression of genetic risks. An increasing number of studies demonstrate that the effects of polygenic risk scores (PRS) may be biased by the inclusion of heritable environments as covariates when the environment is influenced by unmeasured confounding variables, an example of collider bias. Inclusion of the principal components of observed confounders as covariates may correct for the effect of unmeasured confounders.
METHODS: A simulation study was conducted to test principal components analysis (PCA) as a correction for collider bias. …