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Articles 21181 - 21210 of 24703
Full-Text Articles in Entire DC Network
Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald
Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald
University Studies Faculty Publications and Presentations
With society’s increasing dependence on technology infrastructure, the importance of securing the computers, networks, data, and algorithms that run our digital and physical lives is becoming critical. To equip the next generation of citizens for the challenges ahead, an effort is underway to introduce security content early in a student’s academic career. It is important that these efforts broaden participation and increase diversity in the field. While many camps and curricula focus on introducing technical content and skills related to cybersecurity, such approaches can prematurely limit how students view career opportunities in the field, potentially limiting those who ultimately pursue …
Pdxscholar Annual Report 2016, Karen Bjork, Sherry Buchanan, David Coate, Bertrand Robinson, Stacey Schlatter
Pdxscholar Annual Report 2016, Karen Bjork, Sherry Buchanan, David Coate, Bertrand Robinson, Stacey Schlatter
Library Faculty and Staff Publications and Presentations
This report details the sixth year of operation for PDXScholar, Portland State University's institutional repository, as well as the growth of Portland State University Library's publishing services. The report covers the period between January 1, 2016 and December 31, 2016.
Do Direct Behavior Rating-Single Item Scales (Dbr-Sis) Help Students With Attention Deficit Hyperactivity Disorder Self-Regulate?, Regina M. Hildenbrand-Moore
Do Direct Behavior Rating-Single Item Scales (Dbr-Sis) Help Students With Attention Deficit Hyperactivity Disorder Self-Regulate?, Regina M. Hildenbrand-Moore
All-Inclusive List of Electronic Theses and Dissertations
As accountability of teachers has been pushed to the forefront, it has been speculated that tolerance for students with behavior problems will dissipate (Menzies & Lane, 2011). Strategies that are efficient and effective are needed to help monitor behavior change and to help students learn to regulate their behavior. Attention-Deficit/Hyperactivity Disorder (ADHD) is the most common disorder of self-regulation (Barkley, 1997). An estimated three million children in the United States take medications for attention and behavior problems associated with deficits in self-regulation (Olfson, Marcus, Weissman, & Jensen, 2002). Self-regulation interventions have been proposed as methods that are effective in increasing …
Effect Of Directed Study Of Mathematics Vocabulary On Standardized Mathematics Assessment Questions, Adel Marlane Waite
Effect Of Directed Study Of Mathematics Vocabulary On Standardized Mathematics Assessment Questions, Adel Marlane Waite
All-Inclusive List of Electronic Theses and Dissertations
The problems under investigation included (a) Did a directed study of mathematics vocabulary significantly affect student performance levels on standardized mathematical questions? and (b) Did the strategies used in this study significantly affect student performance levels on standardized mathematical questions? The population consisted of eighth-grade pre-algebra students from two different middle schools in southern Indiana. This quasi-experimental study was of a quantitative, repeated-measures design, using a population of approximately 140 eighth-grade students with a control sample of 37 and an experimental sample of 52. I performed a repeated measures ANCOVA to analyze scores from a mathematics vocabulary posttest for each …
The Psychometric Characteristics Of Two Versions Of A Mathematics Test In Middle School "A Comparative Study, Taghreed Hijazi, Naif Alsharif
The Psychometric Characteristics Of Two Versions Of A Mathematics Test In Middle School "A Comparative Study, Taghreed Hijazi, Naif Alsharif
Journal of Educational and Psychological Studies
The study aimed to investigate the psychometric properties of mathematics achievement test using two versions (paper-pencil and online). The two versions of three mathematics achievement tests were applied on a sample consisting of 958 students distributed to lst, 2nd and 3rd preparatory grades. Each test consisted of 30 items with four alternatives to measure students' problem solving skills and the scientific concepts. The sample of the study was randomly stratified and clustered selected. Item difficulty coefficients of the paper-pencil mathematics achievement test ranged between O.28-0.70, 0.38- 0.62, 048-070 for the lst, 2nd and 3rd preparatory grades respectively. There was between …
The Effect Of Teaching Science Using Mccarthy's' Model (4 Mat) On The 8th Grade Students' Retention Of Learning In Jordan, Abdelsalam M. Adili
The Effect Of Teaching Science Using Mccarthy's' Model (4 Mat) On The 8th Grade Students' Retention Of Learning In Jordan, Abdelsalam M. Adili
Journal of Educational and Psychological Studies
This study aimed at finding the effect of using McCarthy's' Model (4 MAT) on 8th grade students' retention of learning in Jordan. The subjects of the study consisted of 86 students from the eighth grade from one Zarqa city school in the second semester of the academic year 2014/2015. The sample was divided into two groups: the experimental group which was taught using 4 MAT model, and the control group which learned in the traditional way. To achieve the objectives of the study, a quasi-experimental approach was followed, and the researcher prepared a valid and reliable achievement test which aimed …
Longer-Term Impact Of Highand Low Temperature On Mortality: An International Study To Clarify Length Of Mortality Displacement, Ben Armstrong, Michelle Bell, Micheline De Sousa Zanotti Stagliorio Coelho, Yue Liang Leon Guo, Yuming Guo, Patrick J. Goodman, Masahiro Hashizume, Yasushi Honda, Ho Kim, Eric Lavigne, Paola Michelozzi, Paulo Hilario Nascimento Saldiva, Joel Schwartz, Matteo Scortichini, Francesco Sera, Aurelio Tobias, Shilu Tong, Chang Fu Wu, Antonella Zanobetti, Ariana Zeka, Antonio Gasparrini
Longer-Term Impact Of Highand Low Temperature On Mortality: An International Study To Clarify Length Of Mortality Displacement, Ben Armstrong, Michelle Bell, Micheline De Sousa Zanotti Stagliorio Coelho, Yue Liang Leon Guo, Yuming Guo, Patrick J. Goodman, Masahiro Hashizume, Yasushi Honda, Ho Kim, Eric Lavigne, Paola Michelozzi, Paulo Hilario Nascimento Saldiva, Joel Schwartz, Matteo Scortichini, Francesco Sera, Aurelio Tobias, Shilu Tong, Chang Fu Wu, Antonella Zanobetti, Ariana Zeka, Antonio Gasparrini
Articles
In many places, daily mortality has been shown to increase after days with particularly high or low temperatures, but such daily time-series studies cannot identify whether such increases reflect substantial life shortening or short-term displacement of deaths (harvesting).
Subjective Usability, Mental Workload Assessments And Their Impact On Objective Human Performance, Luca Longo
Subjective Usability, Mental Workload Assessments And Their Impact On Objective Human Performance, Luca Longo
Articles
Self-reporting procedures and inspection methods have been largely employed in the fields of interaction and web-design for assessing the usability of interfaces. However, there seems to be a propensity to ignore features related to end-users or the context of application during the usability assessment procedure. This research proposes the adoption of the construct of mental workload as an additional aid to inform interaction and web-design. A user-study has been performed in the context of human-web interaction. The main objective was to explore the relationship between the perception of usability of the interfaces of three popular web-sites and the mental workload …
A Conceptual Framework For A Software Development Process Based On Computational Thinking, Catherine Higgins, Ciaran O'Leary, Orla Hanratty, Fredrick Mtenzi
A Conceptual Framework For A Software Development Process Based On Computational Thinking, Catherine Higgins, Ciaran O'Leary, Orla Hanratty, Fredrick Mtenzi
Articles
A software development process is a mechanism for problem solving to help software developers plan, design and structure the development of software to solve a problem. Without a process to guide the structured evolution of a solution, it is extremely likely that at least some aspect of the resulting software will be omitted or incorrectly implemented. Even though the importance of utilising a software process for solving problems is accepted in the business and academic communities, it is a topic that is addressed very lightly (if at all) in most freshman undergraduate computing courses with most courses focussing on programming …
Operator Locality In The Quantum Simulation Of Fermionic Models, Vojtěch Havlíček, Matthias Troyer, James D. Whitfield
Operator Locality In The Quantum Simulation Of Fermionic Models, Vojtěch Havlíček, Matthias Troyer, James D. Whitfield
Dartmouth Scholarship
Simulating fermionic lattice models with qubits requires mapping fermionic degrees of freedom to qubits. The simplest method for this task, the Jordan-Wigner transformation, yields strings of Pauli operators acting on an extensive number of qubits. This overhead can be a hindrance to implementation of qubit-based quantum simulators, especially in the analog context. Here we thus review and analyze alternative fermion-to-qubit mappings, including the two approaches by Bravyi and Kitaev and the Auxiliary Fermion transformation. The Bravyi-Kitaev transform is reformulated in terms of a classical data structure and generalized to achieve a further locality improvement for local fermionic models on a …
Student Surveillance, Racial Inequalities, And Implicit Racial Bias, Jason P. Nance
Student Surveillance, Racial Inequalities, And Implicit Racial Bias, Jason P. Nance
UF Law Faculty Publications
In the wake of high-profile incidents of school violence, school officials have increased their reliance on a host of surveillance measures to maintain order and control in their schools. Paradoxically, such practices can foster hostile environments that may lead to even more disorder and dysfunction. These practices may also contribute to the so-called “school-to-prison pipeline” by pushing more students out of school and into the juvenile justice system. However, not all students experience the same level of surveillance. This Article presents data on school surveillance practices, including an original empirical analysis of restricted data recently released by the U.S. Department …
Using Thermal Infrared Imagery To Estimate Soil Hydraulic Parameters: A Novel Approach, Matthew B. Thomas
Using Thermal Infrared Imagery To Estimate Soil Hydraulic Parameters: A Novel Approach, Matthew B. Thomas
Undergraduate Theses, Professional Papers, and Capstone Artifacts
In this study, skin temperature measured with a thermal infrared (TIR) camera was used to estimate soil hydraulic parameters. These physical properties that control how soils transport and retain water are notoriously difficult to measure in the field due to spatial variability. Laboratory experiments were set up to record surface skin temperature response in a clean soil column using a TIR camera after an artificial wetting event. An array of thermocouples, a net radiometer, heat flux sensor and weather station were used to constrain the TIR data and the energy budget during the experiment. The soil column surface was then …
A Retrospective On George Macdonald: Poet, Novelist, Preacher, Roderick Mcgillis
A Retrospective On George Macdonald: Poet, Novelist, Preacher, Roderick Mcgillis
North Wind: A Journal of George MacDonald Studies
No abstract provided.
Constructing A Sense Of Story: One Block At A Time, Joanne M. Robertson-Eletto, Smita Guha, Marina Marinelli
Constructing A Sense Of Story: One Block At A Time, Joanne M. Robertson-Eletto, Smita Guha, Marina Marinelli
Graduate School of Education Publications and Research
This photo essay focuses upon the literacy practices of two groups of preschoolers as they built, illustrated, and dictated stories in response to their participation in a “Castle Project.” Data, including literacy artifacts, photodocumentation, sociodramatic play scenarios, and conversations are qualitatively analyzed, coded, and evaluated over a three month period. We use a narrative approach to describe the three- and four-year-olds’ talk, actions, and ideas, and the ways block play facilitated their sense of story and motivation to write. We suggest a reciprocity of thinking between the building and composing processes. Preschoolers’ story ideas, we deduce, were conceptualized and rehearsed …
A Study Of High Temperature Heat Pipes And The Impact Of Magnetic Field On The Flow Of Liquid Metal, Udit Sharma
A Study Of High Temperature Heat Pipes And The Impact Of Magnetic Field On The Flow Of Liquid Metal, Udit Sharma
Dissertations, Master's Theses and Master's Reports
A study of high temperature heat pipe was conducted to understand its characteristics. A review of working fluid, temperature, wick structure, problems, operational limit and applications was done. Alkali metal were concluded as the most viable candidate for the working fluid.
The impact of three parameters namely magnetic field, heat flux and temperature was analyzed on the performance of HTHP (High Temperature Heat Pipe). The presence of magnetic field had the most considerable impact on reducing the pumping limit of the heat pipe while the temperature had almost negligible effect. Magnetic field results in the pressure drop and adversely affect …
Using Remote Site Incubators For Re-Introduction Of Arctic Graylng (Thymallus Arcticus) To The Big Manistee Watershed, Sunflower Wilson
Using Remote Site Incubators For Re-Introduction Of Arctic Graylng (Thymallus Arcticus) To The Big Manistee Watershed, Sunflower Wilson
Dissertations, Master's Theses and Master's Reports
Remote Site Incubators (RSIs) were developed for the incubation of salmonid eggs directly at a field site to enhance success and imprinting of young. These have been employed in the re-establishment of Arctic Grayling in Montana and are being laboratory tested for possible reintroduction of this species in the Big Manistee River, MI. Arctic Grayling, Rainbow and Brook Trout eggs, obtained from state hatcheries, were reared in a laboratory using flow through lake water to assess egg and fry survival using RSIs. Dead eggs and fry were removed daily and observations of developmental stages recorded. Rainbow Trout eggs were evaluated …
Analysis Of Aeroelastic Effects On The 3-Dimensional Interference Of Wind-Turbine Rotors, Anurag Rajan
Analysis Of Aeroelastic Effects On The 3-Dimensional Interference Of Wind-Turbine Rotors, Anurag Rajan
Dissertations, Master's Theses and Master's Reports
Greater penetration of wind energy demands better utilization of available wind. This has led to a formidable increase in the rotor diameter over the past few years. Bigger rotors call for lighter, more flexible blades to reduce loads and improve fatigue life. As a result, future blades will deform substantially more than the relatively stiff blades of the past. More efficient use of wind power also calls for incorporating advanced active and passive control strategies and increasing the range of velocities over which wind energy is captured. Hence an improvement in the quality of numerical simulations capable of capturing the …
Control Of A Powered Ankle-Foot Prosthesis: From Perception To Impedance Modulation, Guilherme Aramizo Ribeiro
Control Of A Powered Ankle-Foot Prosthesis: From Perception To Impedance Modulation, Guilherme Aramizo Ribeiro
Dissertations, Master's Theses and Master's Reports
Active ankle prostheses controllers are demonstrating gaining smart features to improve the safety and comfort offor users. The perception of user intention to modulate the ankle dynamics is a well-known example of such feature. But not much work focused on the perception of the environment, nor how the environment should be included in the mechanical design and control of the prosthesisprostheses. The proposed work aims to improve the feasibility of integrate the environment perception integration intoto the prostheses controllersler, and to define the desired ankle dynamics, as mechanical impedance, duringof the human walk on different environmental settings. As a preliminary …
Modeling Mass And Thermal Transport In Thin Porous Media Of Pem Fuel Cells, Vinaykumar Konduru
Modeling Mass And Thermal Transport In Thin Porous Media Of Pem Fuel Cells, Vinaykumar Konduru
Dissertations, Master's Theses and Master's Reports
Water transport in the Porous Transport Layer (PTL) plays an important role in the efficient operation of polymer electrolyte membrane fuel cells (PEMFC). Excessive water content as well as dry operating conditions are unfavorable for efficient and reliable operation of the fuel cell. The effect of thermal conductivity and porosity on water management are investigated by simulating two-phase ow in the PTL of the fuel cell using a network model. In the model, the PTL consists of a pore-phase and a solid-phase. Different models of the PTLs are generated using independent Weibull distributions for the pore-phase and the solid-phase. The …
Development Of An Evaporation Sub-Model And Simulation Of Multiple Droplet Impingement In Volume Of Fluid Method, Sathya Prasad Potham
Development Of An Evaporation Sub-Model And Simulation Of Multiple Droplet Impingement In Volume Of Fluid Method, Sathya Prasad Potham
Dissertations, Master's Theses and Master's Reports
Droplet collision and impingement on a substrate are widely observed phenomenon in many applications like spray injection of Internal Combustion Engines. Existing Lagrangian models do not provide a comprehensive picture of the outcome of these events and may involve model constants requiring experimental data for validation. Physics based models like Volume of Fluid (VOF) method involve no parametric tuning and are more accurate. The aim of this thesis is to extend the basic VOF method with an evaporation sub-model including an additional vapor phase and implement this model in an open source Computational Fluid Dynamics (CFD) software, OpenFOAM. The new …
Influence Of Magnetic Nanoparticles And Magnetic Stress On An Ionic Liquid Electrospray Source, Kurt Joseph Terhune
Influence Of Magnetic Nanoparticles And Magnetic Stress On An Ionic Liquid Electrospray Source, Kurt Joseph Terhune
Dissertations, Master's Theses and Master's Reports
Two electrospray sources were developed to operate on an ionic liquid ferrofluid; one source was a pressure‑fed capillary electrospray source and the other was a novel electrospray source which used a magnetically‑induced instability to produce a peak from which an electric field could extract electrospray. Multiple characteristics of electrospray operation were examined for both sources using faraday plates/cups, a quartz crystal microbalance, a retarding potential analyzer, and a time-of-flight mass spectrometer. The ILFF electrosprays for a capillary source were shown to operate in a mixed ion/droplet regime. The mass flow of the electrospray beam was primarily transported by larger particles …
Genome Editing And The Jurisprudence Of Scientific Empiricism, Paul Enriquez
Genome Editing And The Jurisprudence Of Scientific Empiricism, Paul Enriquez
Vanderbilt Journal of Entertainment & Technology Law
Humankind has reached, in tow by the hand of a scientific breakthrough called CRISPR, the Rubicon of precise genetic manipulation first envisioned over fifty years ago. Despite CRISPR's renown in science and its power to transform the world, it remains virtually unaddressed in legal scholarship. In the absence of on-point law, the scientific community has attempted to reach some consensus to preempt antagonistic regulation and prescribe subjective standards of use under the guise of a priori scientific empiricism. Significant and complex legal issues concerning this technology are emerging, and the void in legal scholarship is no longer tolerable.
This Article …
Effective Interactions Between Local Hopping Modulations On The Square Lattice, Huu T. Do
Effective Interactions Between Local Hopping Modulations On The Square Lattice, Huu T. Do
Electronic Theses and Dissertations
No abstract provided.
Metallosalen-Based Polymers For Reduction Of Carbon Dioxide, Cherawat Kaewyai
Metallosalen-Based Polymers For Reduction Of Carbon Dioxide, Cherawat Kaewyai
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, a series of novel asymmetric copper- and nickel-salens bearing thiophene-based substituents were successfully synthesized and characterized by nuclear magnetic resonance spectroscopy and mass spectrometry. Homogeneous electrocatalytic activities of these monomers toward reduction of CO2 were investigated using cyclic voltammetry technique. Electrochemical studies showed these salen monomers are able to serve as catalysts in the electrochemical reduction of CO2 due to the significantly increase of the current observed under CO2-saturated condition, compared with those found under the N2-saturated one. Results also revealed that insertion of the carbon-carbon triple-bond between the thiophene-based substituents and the salen core led to …
ไฮโดรจิเนชันของคาร์บอนไดออกไซด์เป็นโอเลฟินส์บนตัวเร่งปฏิกิริยาเหล็กและโคบอลต์บนคาร์บอน, เจนจิรา รัตถิวัลย์
ไฮโดรจิเนชันของคาร์บอนไดออกไซด์เป็นโอเลฟินส์บนตัวเร่งปฏิกิริยาเหล็กและโคบอลต์บนคาร์บอน, เจนจิรา รัตถิวัลย์
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้มีวัตถุประสงค์เพื่อเตรียมคาร์บอนทรงกลมในการนำมาใช้เป็นตัวรองรับสำหรับการเตรียมตัวเร่งปฏิกิริยาและศึกษากระบวนการไฮโดรจิเนชันของคาร์บอนไดออกไซด์เป็นโอเลฟินส์บนตัวเร่งปฏิกิริยาเหล็กและโคบอลต์บนคาร์บอนทรงกลมที่เตรียมได้ โดยสามารถเตรียมคาร์บอนทรงกลมจากไซโลสด้วยวิธีไฮโดรเทอร์มอลคาร์บอไนเซชัน โดยตัวเร่งปฏิกิริยาโคบอลต์ที่เตรียมจากตัวรองรับคาร์บอนทรงกลม (10%Co/CS-IMP) มีประสิทธิภาพที่ดีกว่าเมื่อเทียบกับตัวเร่งปฏิกิริยาโคบอลต์ที่เตรียมจากตัวรองรับเส้นใยซิลิกาและซิลิกา (10%Co/SF-IMP, 10%Co/SiO2-IMP) จากนั้นทำการศึกษาเปรียบเทียบระหว่างใช้ตัวเร่งปฏิกิริยาโลหะเดี่ยว (10%Co/CS-IMP) และตัวเร่งปฏิกิริยาโลหะคู่ที่มีตัวส่งเสริม (10%(Co-Fe)/K/CS-IMP) พบว่า ตัวส่งเสริมโพแทสเซียมช่วยทำให้ปฏิกิริยาเกิดสารไฮโดรคาร์บอนโอเลฟินส์ ทำการเปรียบเทียบการเตรียมตัวเร่งปฏิกิริยาด้วยวิธีเคลือบฝัง (Impregnation, IMP) และวิธีไฮโดรเทอร์มอลคาร์บอไนเซชัน (Hydrothermal carbonization, HC) พบว่าวิธีเคลือบฝังให้ตัวเร่งปฏิกิริยาที่มีประสิทธิภาพในการเร่งปฏิกิริยาไฮโดรจิเนชันของคาร์บอนไดออกไซด์ และจากการศึกษาสภาวะที่เหมาะสมในการทำปฏิกิริยาไฮโดรจิเนชันของคาร์บอนไดออกไซด์ พบว่า ที่ความดันที่ 25 บาร์, อุณหภูมิที่ใช้ทำปฏิกิริยา เท่ากับ 300 องศาเซลเซียส, ค่าอัตราส่วนของน้ำหนักตัวเร่งปฏิกิริยาต่ออัตราเร็วของสารป้อน (W/F) เท่ากับ 10 กรัม(ตัวเร่งปฏิกิริยา)·ชั่วโมง/โมล โดยใช้ตัวเร่งปฏิกิริยา 15%(Co-Fe)/K/CS-IMP ให้ประสิทธิภาพที่ดีที่สุดในการเร่งปฏิกิริยาไฮโดรจิเนชันของคาร์บอนไดออกไซด์ โดยให้ค่าร้อยละการเปลี่ยนของคาร์บอนไดออกไซด์ที่สูงที่สุด เท่ากับ ร้อยละ 59.98 มีค่าร้อยละการเลือกเกิดและร้อยละผลผลิตของสารไฮโดรคาร์บอนโอเลฟินส์ เท่ากับ ร้อยละ 11.17 และ 6.50 ตามลำดับ และทำการศึกษาคุณลักษณะของตัวเร่งปฏิกิริยาด้วยเทคนิคการวิเคราะห์อุณหภูมิของการรีดิวซ์ตัวเร่งปฏิกิริยา, เทคนิคการดูดซับทางกายภาพด้วยแก๊สไนโตรเจน, เทคนิคการเลี้ยวเบนของรังสีเอกซ์ และการศึกษาลักษณะทางสัณฐานวิทยาของด้วยกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด
Characterization Of Non-Volatile Chemical Constituents In Thai Wineusing Liquid Chromatography-Tandem Mass Spectrometry, Premkamol Karapakdee
Characterization Of Non-Volatile Chemical Constituents In Thai Wineusing Liquid Chromatography-Tandem Mass Spectrometry, Premkamol Karapakdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed and validated for simultaneous determination of targeted non-volatile compounds, such as five organic acids and twenty phenolic compounds, in 19 wine samples including 2 imported red wines, 15 Thai red wines and 2 fruit wines, using the following HPLC-MS/MS conditions: a C18 analytical column and gradient elution of A: B mobile phase at flow rate 0.4 mL/min, where A and B are 0.1% v/v formic acid in water and 0.1% v/v formic acid in methanol. The limit of detection (LOD) and the limit of quantitation (LOQ) for these …
Harmonic Syntax Of The Twelve-Bar Blues Form: A Corpus Study, Jonah Katz
Harmonic Syntax Of The Twelve-Bar Blues Form: A Corpus Study, Jonah Katz
Faculty & Staff Scholarship
THIS PAPER DESCRIBES THE CONSTRUCTION AND analysis of a corpus of harmonic progressions from 12-bar blues forms included in the jazz repertoire collection The Real Book. A novel method of coding and analyzing such corpus data is developed, with a notion of ‘‘possible harmonic change’’ derived from the corpus and logit mixed-effects regression models that describe the difference between actually occurring harmonic events and possible but non-occurring ones in terms of various sets of theoretical constructs. Models using different sets of constructs are compared using the Bayesian Information Criterion, which assesses the accuracy and efficiency of each model. The principal …
Nature Of Magnetic Ordering In Cobalt‐Based Spinels, Subhash Thota, Sobhit Singh
Nature Of Magnetic Ordering In Cobalt‐Based Spinels, Subhash Thota, Sobhit Singh
Faculty & Staff Scholarship
In this chapter, the nature of magnetic ordering in cobalt‐based spinels Co3O4, Co2SnO4, Co2TiO4, and Co2MnO4 is reviewed, and some new results that have not been reported before are presented. A systematic comparative analysis of various results available in the literature is presented with a focus on how occupation of the different cations on the A‐ and B‐sites and their electronic states affect the magnetic properties. This chapter specifically focuses on the issues related to (i) surface and finite‐size effects in pure Co3O4, (ii) magnetic‐compensation effect, (iii) co‐existence of ferrimagnetism and spin‐glass‐like ordering, (iv) giant coercivity (HC) and exchange bias …
Exploring The Gender Gap In The Conceptual Survey Of Electricity And Magnetism, Rachel Henderson, Gay Stewart, John Stewart, Lynnette Michaluk, Adrienne Traxler
Exploring The Gender Gap In The Conceptual Survey Of Electricity And Magnetism, Rachel Henderson, Gay Stewart, John Stewart, Lynnette Michaluk, Adrienne Traxler
Faculty & Staff Scholarship
The “gender gap” on various physics conceptual evaluations has been extensively studied. Men’s average pretest scores on the Force Concept Inventory and Force and Motion Conceptual Evaluation are 13% higher than women’s, and post-test scores are on average 12% higher than women’s. This study analyzed the gender differences within the Conceptual Survey of Electricity and Magnetism (CSEM) in which the gender gap has been less well studied and is less consistent. In the current study, data collected from 1407 students (77% men, 23% women) in a calculus-based physics course over ten semesters showed that male students outperformed female students on …
Novel Shape Memory Polymer From Bio-Based Polybenzoxazine/Bio-Based Epoxy Copolymers, Phakakrong Hombunma
Novel Shape Memory Polymer From Bio-Based Polybenzoxazine/Bio-Based Epoxy Copolymers, Phakakrong Hombunma
Chulalongkorn University Theses and Dissertations (Chula ETD)
Shape memory polymers (SMPs) are known as smart polymer materials which can be deformed and fixed in a temporary shape and can recover to its original shape upon an external stimulus such as temperature which is the main stimulus for general SMPs. In this research, a renewable natural resource based on vanillin-furfurylamine benzoxazine (V-fa) and eugenol-furfurylamine benzoxazine (E-fa) are developed to substitute the use of petroleum based polybenzoxazine. The as-synthesized V-fa and E-fa show the degradation temperature at 5% weight loss to be as high as 343 and 310°C and char content to be 66 and 54%, respectively. Effects of …