2,931 research outputs found
The Effective Use of Multimedia Distance Learning Technology: The Role of Technology Self-Efficacy, Attitudes, Reliability, Use and Distance in a Global Multimedia Distance Learning Classroom
According to the 1999 ASTD State of the Industry Report, the use of multimedia distance learning (MDL) technology for training delivery has increased substantially over the past few years. However, few empirical studies have been conducted that rigorously examine the factors that determine the effectiveness of MDL courses. In this study, we examine participants’ technology self-efficacy and attitudes toward technology (measured before/after training), and perceptions of technology reliability, effective use, and distance (measured after training) as antecedents to ratings of training effectiveness (general effectiveness, specific effectiveness, learning effectiveness; measured after training) in an international HRM course. In a sample of 52 participants from four countries we hypothesize that technology self-efficacy will affect participants’ attitudes toward technology; attitudes toward technology will affect participants’ perceptions of training effectiveness. In addition, we hypothesize that technology reliability and effective use will affect participants’ perceptions of classroom distance; distance perceptions will affect participants’ perceptions of training effectiveness. Finally, we hypothesize that both technology attitudes and distance perceptions will be related to participants’ perceptions of training effectiveness controlling for technology self-efficacy, reliability, and effective use.
The results indicate that attitudes toward technology completely/partially mediated the relationship between technology self-efficacy and the three measures of effectiveness. Distance perceptions completely/partially mediated the relationship between technology reliability and effectiveness. Effective technology use was not significantly related to effectiveness. Finally, attitudes toward technology and distance perceptions explained a significant or marginally significant amount of variance in the effectiveness measures after controlling for technology self-efficacy, reliability, and effective use
Prominences: The Key to Understanding Solar Activity
Prominences are spectacular manifestations of both quiescent and eruptive solar activity. The largest examples can be seen with the naked eye during eclipses, making prominences among the first solar features to be described and catalogued. Steady improvements in temporal and spatial resolution from both ground- and space-based instruments have led us to recognize how complex and dynamic these majestic structures really are. Their distinguishing characteristics - cool knots and threads suspended in the hot corona, alignment along inversion lines in the photospheric magnetic field within highly sheared filament channels, and a tendency to disappear through eruption - offer vital clues as to their origin and dynamic evolution. Interpreting these clues has proven to be contentious, however, leading to fundamentally different models that address the basic questions: What is the magnetic structure supporting prominences, and how does so much cool, dense plasma appear in the corona? Despite centuries of increasingly detailed observations, the magnetic and plasma structures in prominences are poorly known. Routine measurements of the vector magnetic field in and around prominences have become possible only recently, while long-term monitoring of the underlying filament-channel formation process also remains scarce. The process responsible for prominence mass is equally difficult to establish, although we have long known that the chromosphere is the only plausible source. As I will discuss, however, the motions and locations of prominence material can be used to trace the coronal field, thus defining the magnetic origins of solar eruptions. A combination of observations, theory, and numerical modeling must be used to determine whether any of the competing theories accurately represents the physics of prominences. I will discuss the criteria for a successful prominence model, compare the leading models, and present in detail one promising, comprehensive scenario for prominence formation and evolution that could answer the two questions posed above
CME Initiation and Reconnection
Coronal mass ejections (CMEs) are the most massive explosions in the heliosphere, and the primary drivers of geoeffective space weather. This talk will be focused on fast CMEs, which travel at Alfvenic speeds as high as 2500 km/s. These ejections are associated with solar flares, prominence eruptions, and energetic particles accelerated near the Sun and in interplanetary space. CMEs require sufficient energy storage, in the form of magnetic stress, and rapid release of this energy. Although it is generally agreed that magnetic reconnection is the key to fast CME initiation, different models incorporate reconnection in different ways. One promising model --- the breakout scenario --- involves reconnection in two distinct yet interconnected locations: breakout reconnection ahead of the CME, and flare reconnect ion behind it. This model has been validated through 2D and 3D MHD simulations and favorable comparison with the observed properties of many fast CMEs. I will discuss what we have learned about the onset and evolution of breakout and flare reconnect ion from recent high-resolution 2D simulations of CME initiation with adaptive mesh refinement and numerical resistivity
Effects of Sleep Duration, Sleep Quality, and Time of Day on Executive Function Performance in Children
Executive functions are the cognitive abilities that include self-regulation, inhibition of responding, planning, and mental flexibility. Previous studies on executive functions I I have focused on people with ADHD and other impairments. Studies on sleep and cognitive function abilities have focused on the effects of lack of sleep and the ability to perform executive function tasks. This study examined the cognitive abilities of children with no impairment in relationship to Time of Day, Sleep Duration and Sleep Quality.
Thirty children ranging from age 7 to age 12 were recruited from the area. A self-report questionnaire on typical Sleep Duration and Sleep Quality, and the Child Behavior Checklist were sent one week in advance to be completed before the time of testing. The children were tested at either 9AM or 3PM on five executive function tasks. The executive function tasks included the Connors Continuous Performance Test, Digit Span, Tower of London, Controlled Oral Word Association Test and the Wisconsin Card Sorting Task.
This study showed that when the participants perceived themselves to be well rested, (sleep duration and sleep quality self-reports) cognitive performance in some executive function tasks was more proficient, and this effect varied as a function of Time of Day of testing
Cooperative Extension Service Online Registration Service
Prior to the development of this project, the South Dakota Cooperative Extension Service did not have an online registration system. Workshop participants registered manually; by telephone, by mail or at the door. This was an inefficient use of employee time and other resources. It was also inconvenient for participants. To answer this need, an online registration system was developed. ColdFusion was used as a database-to-web gateway. This database driven system allows the workshop manager to setup and manage the registration pages. The manager and the administrator pages are located on the Extension Services private intranet site. These include workshop management pages and participant management pages. The public pages are located the internet site and include the workshop search page and the individual registration pages
Lessons Learned from Development of a Software Tool to Support Academic Advising
We detail some lessons learned while designing and testing a
decision-theoretic advising support tool for undergraduates at a large state
university. Between 2009 and 2011 we conducted two surveys of over 500 students
in multiple majors and colleges. These surveys asked students detailed
questions about their preferences concerning course selection, advising, and
career paths. We present data from this study which may be helpful for faculty
and staff who advise undergraduate students. We find that advising support
software tools can augment the student-advisor relationship, particularly in
terms of course planning, but cannot and should not replace in-person advising.Comment: 5 Figures, revised version including more figures and
cross-referencin
Forcing adsorption of a tethered polymer by pulling
We present an analysis of a partially directed walk model of a polymer which at one end is tethered to a sticky surface and at the other end is subjected to a pulling force at fixed angle away from the point of tethering. Using the kernel method, we derive the full generating function for this model in two and three dimensions and obtain the respective phase diagrams. We observe adsorbed and desorbed phases with a thermodynamic phase transition in between. In the absence of a pulling force this model has a secondorder thermal desorption transition which merely gets shifted by the presence of a lateral pulling force. On the other hand, if the pulling force contains a non-zero vertical component this transition becomes first order. Strikingly, we find that, if the angle between the pulling force and the surface is below a critical value, a sufficiently strong force will induce polymer adsorption, no matter how large the temperature of the system. Our findings are similar in two and three dimensions, an additional feature in three dimensions being the occurrence of a re-entrance transition at constant pulling force for low temperature, which has been observed previously for this model in the presence of pure vertical pulling. Interestingly, the re-entrance phenomenon vanishes under certain pulling angles, with details depending on how the three-dimensional polymer is modeled
Strain Gauge Balance Calibration and Data Reduction at NASA Langley Research Center
This paper will cover the standard force balance calibration and data reduction techniques used at Langley Research Center. It will cover balance axes definition, balance type, calibration instrumentation, traceability of standards to NIST, calibration loading procedures, balance calibration mathematical model, calibration data reduction techniques, balance accuracy reporting, and calibration frequency
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