129 research outputs found
Survey on Individual Differences in Visualization
Developments in data visualization research have enabled visualization
systems to achieve great general usability and application across a variety of
domains. These advancements have improved not only people's understanding of
data, but also the general understanding of people themselves, and how they
interact with visualization systems. In particular, researchers have gradually
come to recognize the deficiency of having one-size-fits-all visualization
interfaces, as well as the significance of individual differences in the use of
data visualization systems. Unfortunately, the absence of comprehensive surveys
of the existing literature impedes the development of this research. In this
paper, we review the research perspectives, as well as the personality traits
and cognitive abilities, visualizations, tasks, and measures investigated in
the existing literature. We aim to provide a detailed summary of existing
scholarship, produce evidence-based reviews, and spur future inquiry
Balancing Human and Machine Contributions in Human Computation Systems
Many interesting and successful human computation systems leverage the complementary computational strengths of both humans and machines to solve these problems. In this chapter, we examine Human Computation as a type of Human-Computer Collaborationācollaboration involving at least one human and at least one computational agent. We discuss recent advances in the open area of function allocation, and explore how to balance the contributions of humans and machines in computational systems. We then explore how human-computer collaborative strategies can be used to solve problems that are difficult or computationally infeasible for computers or humans alone
Priming Locus of Control to Affect Performance
Recent research suggests that the personality trait Locus of Control (LOC) can be a reliable predictor of performance when learn- ing a new visualization tool. While these results are compelling and have direct implications to visualization design, the relation- ship between a userās LOC measure and their performance is not well understood. We hypothesize that there is a dependent relation- ship between LOC and performance; specifically, a personās orientation on the LOC scale directly influences their performance when learning new visualizations. To test this hypothesis, we conduct an experiment with 300 subjects using Amazonās Mechanical Turk. We adapt techniques from personality psychology to manipulate a userās LOC so that users are either primed to be more internally or externally oriented on the LOC scale. Replicating previous studies investigating the effect of LOC on performance, we measure usersā speed and accuracy as they use visualizations with varying visual metaphors. Our findings demonstrate that changing a userās LOC impacts their performance. We find that a change in usersā LOC results in performance changes
Manipulating and Controlling for Personality Effects on Visualization Tasks
Researchers in humanācomputer interaction and visualization have recently been challenged to develop a better understanding of usersā underlying cognitive processes in order to improve system design and evaluation. While existing studies lay a critical foundation for understanding the role of cognitive processes and individual differences in visualization, concretizing the intuition that each user experiences a visual interface through an individual cognitive lens is only half the battle. In this article, we investigate the impact of manipulating usersā personality on observed behavior when using a visualization. In a targeted study, we demonstrate that personality priming can result in changes in behavior when interacting with visualizations. We then discuss how this and similar techniques could be used to control for personality effects when designing and evaluating visualizations systems
The effect of magnetic resonance imaging on mercury release from dental amalgam at 3T and 7T
Objectives To measure mercury release from standardised hydroxyapatite/amalgam constructs during MRI scanning and investigate the impact of static field strength and radiofrequency (RF) power on mercury release. Methods Amalgam was placed into 140 hydroxyapatite disks and matured for 14-days in artificial saliva. The solution was replaced, and samples split into five groups of 28 immediately prior to MRI. One group had no exposure, and the remainder were exposed to either a 3T or 7T MRI scanner, each at high and low RF power. Mercury concentration was measured by inductively coupled plasma mass spectrometry. Groups were compared using one-way ANOVA, and two-way ANOVA for main effects/ interaction of field strength/ RF power. Results Mercury concentration was increased in the 7T groups (high/ low: 15.43/ 11.33 ng mLā1) and 3T high group (3.59) compared to control (2.44). MRI field strength significantly increased mercury release (p < .001) as did RF power (p = .030). At 3T, mercury release was 20.3 times lower than during maturation of dental amalgam, and for the average person an estimated 1.50 ng kgā1 of mercury might be released during one 3T investigation; this is substantially lower than the tolerable weekly intake of 4,000 ng kgā1. Conclusion Mercury release from amalgam shows a measurable increase following MRI, and the magnitude changes with magnetic field strength and RF power. The amount of mercury released is small compared to release during amalgam maturation. Amalgam mercury release during MRI is unlikely to be clinically meaningful and highly likely to remain below safe levels
Detection of the Natural Alpha Decay of Tungsten
The natural alpha decay of 180W has been unambiguously detected for the first
time. The alpha peak is found in a (gamma,beta and neutron)-free background
spectrum. This has been achieved by the simultaneous measurement of phonon and
light signals with the CRESST cryogenic detectors. A half-life of T1/2 = (1.8
+- 0.2) x 10^18 y and an energy release of Q = (2516.4 +- 1.1 (stat.) +- 1.2
(sys.)) keV have been measured. New limits are also set on the half-lives of
the other naturally occurring tungsten isotopes.Comment: Submitted to Physical Review C Revised versio
Recommended from our members
Fabrication of large-volume, low-cost ceramic lanthanum halide scintillators for gamma ray detection : final report for DHS/DNDO/TRDD project TA-01-SL01.
This project uses advanced ceramic processes to fabricate large, optical-quality, polycrystalline lanthanum halide scintillators to replace small single crystals produced by the conventional Bridgman growth method. The new approach not only removes the size constraint imposed by the growth method, but also offers the potential advantages of both reducing manufacturing cost and increasing production rate. The project goal is to fabricate dense lanthanum halide ceramics with a preferred crystal orientation by applying texture engineering and solid-state conversion to reduce the thermal mechanical stress in the ceramic and minimize scintillation light scattering at grain boundaries. Ultimately, this method could deliver the sought-after high sensitivity and <3% energy resolution at 662 keV of lanthanum halide scintillators and unleash their full potential for advanced gamma ray detection, enabling rapid identification of radioactive materials in a variety of practical applications. This report documents processing details from powder synthesis, seed particle growth, to final densification and texture development of cerium doped lanthanum bromide (LaBr{sub 3}:Ce{sup +3}) ceramics. This investigation demonstrated that: (1) A rapid, flexible, cost efficient synthesis method of anhydrous lanthanum halides and their solid solutions was developed. Several batches of ultrafine LaBr{sub 3}:Ce{sup +3} powder, free of oxyhalide, were produced by a rigorously controlled process. (2) Micron size ({approx} 5 {micro}m), platelet shape LaBr{sub 3} seed particles of high purity can be synthesized by a vapor phase transport process. (3) High aspect-ratio seed particles can be effectively aligned in the shear direction in the ceramic matrix, using a rotational shear-forming process. (4) Small size, highly translucent LaBr{sub 3} (0.25-inch diameter, 0.08-inch thick) samples were successfully fabricated by the equal channel angular consolidation process. (5) Large size, high density, translucent LaBr{sub 3} ceramics samples (3-inch diameter, > 1/8-inch thick) were fabricated by hot pressing, demonstrating the superior manufacturability of the ceramic approach over single crystal growth methods in terms of size capability and cost. (6) Despite all these advances, evidence has shown that LaBr{sub 3} is thermally unstable at temperatures required for the densification process. This is particularly true for material near the surface where lattice defects and color centers can be created as bromine becomes volatile at high temperatures. Consequently, after densification these samples made using chemically prepared ultrafine powders turned black. An additional thermal treatment in a flowing bromine condition proved able to reduce the darkness of the surface layer for these densified samples. These observations demonstrated that although finer ceramic powders are desirable for densification due to a stronger driving force from their large surface areas, the same desirable factor can lead to lattice defects and color centers when these powders are densified at higher temperatures where material near the surface becomes thermally unstable
At the world's edge: Reconstructing diet and geographic origins in medieval Iceland using isotope and trace element analyses
Objectives
A multiāisotope study was conducted on individuals buried at SkriĆ°uklaustur monastery (AD 1493ā1554) to investigate their geographic origins and dietary composition. Comparative material from individuals excavated from SkeljastaĆ°ir, an inland farm site was also analyzed.
Materials and methods
Bone collagen was extracted from 50 humans (SkriĆ°uklaustur and SkeljastaĆ°ir) and 25 animals (SkriĆ°uklaustur) and analyzed for Ī“13C, Ī“15N, and Ī“34S. Dental enamel samples from 31 individuals (SkriĆ°uklaustur) were also analyzed for 87Sr/86Sr, Ī“18O, Ī“13C, and trace elements (Pb, Sr, Zn, Ba).
Results
The mean value determined from individuals from SkriĆ°uklaustur (n = 36) was Ī“13C = ā18.7āĀ±ā0.8ā°, Ī“15N = 12.8āĀ±ā1.1ā°, and Ī“34S = 9.0āĀ±ā1.6ā°, whereas at SkeljastaĆ°ir (n = 14), it was Ī“13C = ā20.5āĀ±ā0.8ā°, Ī“15N = 7.8āĀ±ā0.9ā°, and Ī“34S = 9.4āĀ±ā1.6ā°. At SkriĆ°uklaustur, human dental enamel samples (n = 31) provided a 87Sr/86Sr range of 0.7060ā0.7088, Ī“18Ophosphate from 13.9 to 16.1ā° and Ī“13Ccarbonate from ā16.6 to ā12.9ā°. Inferred drinking water (Ī“18Odw) values range from ā12.3 to ā8.9ā°. Sr concentrations range from 25.8 to 156.7 ppm, Ba from 0.11 to 0.81āppm, Zn from 43.8 to 145.8 ppm, and Pb from 0.13 to 9.40āppm.
Discussion
A combination of results indicates that the people from SkriĆ°uklaustur were born in Iceland, but some lived inland during childhood while others lived closer to the coast. Since SkriĆ°uklaustur was a hospital, these individuals may have sought medical treatment at the monastery. The Ī“13C and Ī“15N values determined from bone collagen indicate that the people residing at SkriĆ°uklaustur consumed a diet high in marine protein, while those residing at SkeljastaĆ°ir exhibit values more consistent with terrestrial resources.This research was financed by FornminjasjĆ³Ć°ur (the Archaeology Fund), HĆ”skĆ³lasjĆ³Ć°ur EimskipafĆ©lags Ćslands (the Eimskip University Fund), and the Stable Isotope Biogeochemistry Laboratory (SIBL).Peer Reviewe
- ā¦