24,101 research outputs found
Recommended from our members
A Second Language Acquisition Toolkit for Teaching Introduction to Computing
Introduction to Computing and higher-level programming
courses are common first-year engineering curricula at the
university level and are key in developing logical thought
processes in engineering students. Recent research has shown
that employing second language acquisition (SLA) techniques
to teach programming increases exam performance and student
motivation compared to more classical approaches. However,
the presentation of pedagogical techniques has been largely
limited to higher-level languages with more intuitive linguistic
analogs and has not been extended to lower-level computing
course material. In this paper we present several SLA
techniques and their analogs in a computing course setting and
the results of implementing an SLA strategy in a first-year
engineering course. Statistical analysis shows that students
taught with SLA methods completed quizzes more quickly,
enjoyed recitation more, and had a higher perceived value of
the class when compared with students taught with non-SLA
techniques.Cockrell School of Engineerin
Electrostatic forces for personnel restraints
The feasibility of utilizing electrostatic forces for personnel retention devices on exterior spacecraft surfaces was analyzed. The investigation covered: (1) determination of the state of the art; (2) analysis of potential adhesion surfaces; (3) safety considerations for personnel; (4) electromagnetic force field determination and its effect on spacecraft instrumentation; and (5) proposed advances to current technology based on documentation review, analyses, and experimental test data
"Willingness to Pay for Electric Vehicles and their Attributes"
This article presents a stated preference study of electric vehicle choice using data from a national survey. We used a choice experiment wherein 3029 respondents were asked to choose between their preferred gasoline vehicle and two electric versions of that preferred vehicle. We estimated a latent class random utility model and used the results to estimate the willingness to pay for five electric vehicle attributes: driving range, charging time, fuel cost saving, pollution reduction, and performance. Driving range, fuel cost savings, and charging time led in importance to respondents. Individuals were willing to pay (wtp) from 75 for a mile of added driving range, with incremental wtp per mile decreasing at higher distances. They were willing to pay from 3250 per hour reduction in charging time (for a 50 mile charge). Respondents capitalized about 5 years of fuel saving into the purchase price of an electric vehicle. We simulated our model over a range of electric vehicle configurations and found that people with the highest values for electric vehicles were willing to pay a premium above their wtp for a gasoline vehicle that ranged from 16,000 for electric vehicles with the most desirable attributes. At the same time, our results suggest that battery cost must drop significantly before electric vehicles will find a mass market without subsidy.Electric Vehicles, Stated Preference, Discrete Choice
"Can Vehicle-to-Grid Revenue Help Electric Vehicles on the Market?"
Vehicle-to-grid (V2G) electric vehicles can return power stored in their batteries back to the power grid and be programmed to do so at times when power prices are high. Since providing this service can lead to payments to owners of vehicles, it effectively reduces the cost of electric vehicles. Using data from a national stated preference survey (n = 3029), this paper presents the first study of the potential consumer demand for V2G electric vehicles. In our choice experiment, 3029 respondents compared their preferred gasoline vehicle with two V2G electric vehicles. The V2G vehicles were described by a set of electric vehicle attributes and V2G contract requirements such as ârequired plug-in timeâ and âguaranteed minimum driving rangeâ. The contract requirements specify a contract between drivers and a power aggregator for providing reserve power to the grid. Our findings suggest the V2G concept is mostly likely to help EVs on the market if power aggregators operate on pay-as-you-go-basis or provide consumers with advanced cash payment (upfront discounts on the price of EVs) in exchange for V2G restrictions.electric vehicles, vehicle-to-grid, stated preference, latent-class model
Galaxy Morphology from NICMOS Parallel Imaging
We present high resolution NICMOS images of random fields obtained in
parallel to other HST observations. We present galaxy number counts reaching
H=24. The H-band galaxy counts show good agreement with the deepest I- and
K-band counts obtained from ground-based data. We present the distribution of
galaxies with morphological type to H<23. We find relatively fewer irregular
galaxies compared to an I-band sample from the Hubble Deep Field, which we
attribute to their blue color, rather than to morphological K-corrections. We
conclude that the irregulars are intrinsically faint blue galaxies at z<1.Comment: 13 pages, including 4 figures. Accepted for publication in ApJ
Letter
Using practice architectures theory to compare consecutive offerings of the same subject
CONTEXT Two consecutive offerings (2015 and 2016) of the same subject, Concrete Technology and Practice, prompted opposite reactions from students. The academics involved in 2015 and/or 2016 sought to explore the similarities and differences between these consecutive offerings in reflecting on the learning and teaching practices in their classroom. PURPOSE Practice architectures theory provides a framework for examining and understanding the differences between these consecutive offerings of ostensibly the same subject. This paper also provides an example of how a theoretical framework can be used to examine teaching practices â even our own by practitioners who are also acting as researchers in this context. APPROACH Evidence used in comparing the 2015 and 2016 offerings of this subject is drawn from focus group discussions with students and observations of each of the researcher/practitioners involved. Additional data includes the end of semester Student Feedback Survey results including written responses to open-ended questions. RESULTS Differences in aspects of the cultural-discursive, material-economic and socio-political arrangements of the 2015 and 2016 offerings of Concrete Technology and Practice became apparent from the analysis. CONCLUSIONS Using the theory of practice architectures gave us insights into the inter-relationships between the different arrangements inherent in teaching and learning practices. It also highlighted the resilience of âtaken for grantedâ practices
Optimally adapted multi-state neural networks trained with noise
The principle of adaptation in a noisy retrieval environment is extended here
to a diluted attractor neural network of Q-state neurons trained with noisy
data. The network is adapted to an appropriate noisy training overlap and
training activity which are determined self-consistently by the optimized
retrieval attractor overlap and activity. The optimized storage capacity and
the corresponding retriever overlap are considerably enhanced by an adequate
threshold in the states. Explicit results for improved optimal performance and
new retriever phase diagrams are obtained for Q=3 and Q=4, with coexisting
phases over a wide range of thresholds. Most of the interesting results are
stable to replica-symmetry-breaking fluctuations.Comment: 22 pages, 5 figures, accepted for publication in PR
Recommended from our members
Tafassasset: The Saga Continues
In this study, we compare data for two separate Tafassasset stones and supply new oxygen isotope data for our sample. We include a discussion of the debate surrounding the classification of Tafassasset and offer a hypothesis for its origin based upon new information
Current legal and institutional issues in the commercialization of phosphoric acid fuel cells
Legal and institutional factors affecting the development and commercial diffusion of phosphoric acid fuel cells are assessed. Issues for future research and action are suggested. Perceived barriers and potential opportunities for fuel cells in central and dispersed utility operations and on-site applications are reviewed, as well as the general concept of commercialization as applied to emerging energy technologies
Bistability in a simple fluid network due to viscosity contrast
We study the existence of multiple equilibrium states in a simple fluid
network using Newtonian fluids and laminar flow. We demonstrate theoretically
the presence of hysteresis and bistability, and we confirm these predictions in
an experiment using two miscible fluids of different viscosity--sucrose
solution and water. Possible applications include bloodflow, microfluidics, and
other network flows governed by similar principles
- âŠ