355 research outputs found
The Effect of Device When Using Smartphones and Computers to Answer Multiple-Choice and Open-Response Questions in Distance Education
Traditionally in higher education, online courses have been designed for computer users. However, the advent of mobile learning (m-learning) and the proliferation of smartphones have created two challenges for online students and instructional designers. First, instruction designed for a larger computer screen often loses its effectiveness when displayed on a smaller smartphone screen. Second, requiring students to write remains a hallmark of higher education, but miniature keyboards might restrict how thoroughly smartphone users respond to open- response test questions. The present study addressed both challenges by featuring m-learning’s greatest strength (multimedia) and by investigating its greatest weakness (text input).
The purpose of the current study was to extend previous research associated with m- learning. The first goal was to determine the effect of device (computer vs. smartphone) on performance when answering multiple-choice and open-response questions. The second goal was to determine whether computers and smartphones would receive significantly different usability ratings when used by participants to answer multiple-choice and open-response questions. The construct of usability was defined as a composite score based on ratings of effectiveness, efficiency, and satisfaction.
This comparative study used a between-subjects, posttest, experimental design. The study randomly assigned 70 adults to either the computer treatment group or the smartphone treatment group. Both treatment groups received the same narrated multimedia lesson on how a solar cell works. Participants accessed the lesson using either their personal computers (computer treatment group) or their personal smartphones (smartphone treatment group) at the time and location of their choice. After viewing the multimedia lesson, all participants answered the same multiple-choice and open-response posttest questions. In the current study, computer users and smartphone users had no significant difference in their scores on multiple-choice recall questions. On open-response questions, smartphone users performed better than predicted, which resulted in no significant difference between scores of the two treatment groups. Regarding usability, participants gave computers and smartphones high usability ratings when answering multiple-choice items. However, for answering open-response items, smartphones received significantly lower usability ratings than computers
Search and Ranking of High-Rise Apartments based on Residential Quality Index
Increasing urbanization has prompted urban residents to look for solutions to alleviate urban environmental issues such as air and noise pollution. High-rise buildings have become a preferred choice for those looking for cleaner air and a quieter living environment. This disclosure describes techniques to crowdsource floor information from residents of high-rise apartments and to use such information to prioritize search results based on a herein-defined residential quality index (RQI). The techniques address limitations of current map or search applications by providing accurate floor and environmental quality information for high-rise apartments
Experimental Evaluation of Turning Vane Designs for High-speed and Coupled Fan-drive Corners of 0.1-scale Model of NASA Lewis Research Center's Proposed Altitude Wind Tunnel
Two turning vane designs were experimentally evaluated for the fan-drive corner (corner 2) coupled to an upstream diffuser and the high-speed corner (corner 1) of the 0.1 scale model of NASA Lewis Research Center's proposed Altitude Wind Tunnel. For corner 2 both a controlled-diffusion vane design (vane A4) and a circular-arc vane design (vane B) were studied. The corner 2 total pressure loss coefficient was about 0.12 with either vane design. This was about 25 percent less loss than when corner 2 was tested alone. Although the vane A4 design has the advantage of 20 percent fewer vanes than the vane B design, its vane shape is more complex. The effects of simulated inlet flow distortion on the overall losses for corner 1 or 2 were small
Experimental evaluation of corner turning vanes
Two types of turning vane airfoils (a controlled-diffusion shape and a circular arc shape) have been evaluated in the high-speed and fan-drive corners of a 0.1-scale model of NASA Lewis Research Center's proposed Altitude Wind Tunnel. The high-speed corner was evaluated with and without a simulated engine exhaust removal scoop. The fan-drive corner was evaluated with and without the high-speed corner. Flow surveys of pressure and flow angle were taken for both the corners and the vanes to determine their respective losses. The two-dimensional vane losses were low; however, the overall corner losses were higher because three-dimensional flow was generated by the complex geometry resulting from the turning vanes intersecting the end wall. The three-dimensional effects were especially pronounced in the outer region of the circular corner
Detailed flow surveys of turning vanes designed for a 0.1-scale model of NASA Lewis Research Center's proposed altitude wind tunnel
Detailed flow surveys downstream of the corner turning vanes and downstream of the fan inlet guide vanes have been obtained in a 0.1-scale model of the NASA Lewis Research Center's proposed Altitude Wind Tunnel. Two turning vane designs were evaluated in both corners 1 and 2 (the corners between the test section and the drive fan). Vane A was a controlled-diffusion airfoil and vane B was a circular-arc airfoil. At given flows the turning vane wakes were surveyed to determine the vane pressure losses. For both corners the vane A turning vane configuration gave lower losses than the vane B configuration in the regions where the flow regime should be representative of two-dimensional flow. For both vane sets the vane loss coefficient increased rapidly near the walls
Should Antitrust Education be Mandatory (for Law School Administrators)?
The Executive Committee of the Association of American Law Schools has adopted a Statement of Good Practices that purports to limit the times when law schools may make offers to hire faculty members at other schools. Schools are generally not to make offers for indefinite appointments to professors on other faculties after March 1, subject to extension for two months with the consent of the incumbent\u27s dean. They also are not to make offers contemplating resignation from a current faculty position more than two weeks following those deadlines. Proceeding on the assumption that the AALS policy, whose express terms are precatory, speaks to what is in fact an agreement among law schools, this essay concludes this policy memorializes an understanding in violation of Federal antitrust law
An efficient pseudomedian filter for tiling microrrays
<p>Abstract</p> <p>Background</p> <p>Tiling microarrays are becoming an essential technology in the functional genomics toolbox. They have been applied to the tasks of novel transcript identification, elucidation of transcription factor binding sites, detection of methylated DNA and several other applications in several model organisms. These experiments are being conducted at increasingly finer resolutions as the microarray technology enjoys increasingly greater feature densities. The increased densities naturally lead to increased data analysis requirements. Specifically, the most widely employed algorithm for tiling array analysis involves smoothing observed signals by computing pseudomedians within sliding windows, a <it>O</it>(<it>n</it><sup>2</sup>log<it>n</it>) calculation in each window. This poor time complexity is an issue for tiling array analysis and could prove to be a real bottleneck as tiling microarray experiments become grander in scope and finer in resolution.</p> <p>Results</p> <p>We therefore implemented Monahan's HLQEST algorithm that reduces the runtime complexity for computing the pseudomedian of <it>n </it>numbers to <it>O</it>(<it>n</it>log<it>n</it>) from <it>O</it>(<it>n</it><sup>2</sup>log<it>n</it>). For a representative tiling microarray dataset, this modification reduced the smoothing procedure's runtime by nearly 90%. We then leveraged the fact that elements within sliding windows remain largely unchanged in overlapping windows (as one slides across genomic space) to further reduce computation by an additional 43%. This was achieved by the application of skip lists to maintaining a sorted list of values from window to window. This sorted list could be maintained with simple <it>O</it>(log <it>n</it>) inserts and deletes. We illustrate the favorable scaling properties of our algorithms with both time complexity analysis and benchmarking on synthetic datasets.</p> <p>Conclusion</p> <p>Tiling microarray analyses that rely upon a sliding window pseudomedian calculation can require many hours of computation. We have eased this requirement significantly by implementing efficient algorithms that scale well with genomic feature density. This result not only speeds the current standard analyses, but also makes possible ones where many iterations of the filter may be required, such as might be required in a bootstrap or parameter estimation setting. Source code and executables are available at <url>http://tiling.gersteinlab.org/pseudomedian/</url>.</p
Material Strength Effect in the Shock Compression of Alumina
The Hugoniot elastic limits (HEL) of a high-density aluminum oxide ceramic (Lucalox) and a slightly lower-density ceramic (porosity approximately 4%) were determined to be 112±13 and 83±5 kbar, respectively. Above the HEL, the shock-stress-volume Hugoniot curves for both materials are offset by 40 kbar or more above their hydrostatic-pressure-volume curves. These results indicate that shear stresses with magnitudes of about 30–40 kbar persist in aluminum oxide to shock-pressure levels of at least 300 kbar
Toward a universal microarray: prediction of gene expression through nearest-neighbor probe sequence identification
A generic DNA microarray design applicable to any species would greatly benefit comparative genomics. We have addressed the feasibility of such a design by leveraging the great feature densities and relatively unbiased nature of genomic tiling microarrays. Specifically, we first divided each Homo sapiens Refseq-derived gene's spliced nucleotide sequence into all of its possible contiguous 25 nt subsequences. For each of these 25 nt subsequences, we searched a recent human transcript mapping experiment's probe design for the 25 nt probe sequence having the fewest mismatches with the subsequence, but that did not match the subsequence exactly. Signal intensities measured with each gene's nearest-neighbor features were subsequently averaged to predict their gene expression levels in each of the experiment's thirty-three hybridizations. We examined the fidelity of this approach in terms of both sensitivity and specificity for detecting actively transcribed genes, for transcriptional consistency between exons of the same gene, and for reproducibility between tiling array designs. Taken together, our results provide proof-of-principle for probing nucleic acid targets with off-target, nearest-neighbor features
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