17,421 research outputs found
Radial honeycomb core
Core alleviates many limitations of conventional nacelle construction methods. Radical core, made of metals or nonmetals, is fabricated either by joining nodes and then expanding, or by performing each layer and then joining nodes. Core may also be produced from ribbons or strips with joined nodes or ribbons oriented in longitudinal planes
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Continued Value Creation in Crowdsourcing from Creative Process Engagement
Purpose
Crowdsourcing delivers creative ideas for the issuing firm, but participants’ engagement in the creative process also creates additional benefits to firms and participating customers. To investigate if these spill-over values endure over time, this study uses data from two time points, i.e. at submission and after announcement of the contest winners, to investigate the relationship between the degree of a participant’s creative process engagement (CPE) and value creation from a crowdsourcing contest, and how these perceptions of value change over time.
Design/methodology/approach
Data was collected from 154 participants in a crowdsourcing contest at two time points with an online survey: at submission, and after receiving feedback (in term of rankings, rewards, and comments) from the community. Partial Least Square (PLS) path modelling was used to estimate both main and moderating effects.
Findings
CPE increases the perceived value of customers (social and epistemic value) and firms alike (knowledge-sharing intention and customer loyalty), though all but epistemic value decrease over time. Disconfirmation of expectations and need for recognition moderate these effects.
Originality/value
This paper is the first longitudinal study that helps understanding the effect of CPE on value creation from crowdsourcing across time. It also uses the theoretical lens of the honeymoon hangover effect to explain how perceived value changes. The resulting insights into the role of customer engagement in crowdsourcing contests and subsequent value creation will be beneficial to the growing research stream on consumer value co-creation and user innovation
CC Sculptoris: A superhumping intermediate polar
We present high speed optical, spectroscopic and Swift X-ray observations
made during the dwarf nova superoutburst of CC Scl in November 2011. An orbital
period of 1.383 h and superhump period of 1.443 h were measured, but the
principal new finding is that CC Scl is a previously unrecognised intermediate
polar, with a white dwarf spin period of 389.49 s which is seen in both optical
and Swift X-ray light curves only during the outburst. In this it closely
resembles the old nova GK Per, but unlike the latter has one of the shortest
orbital periods among intermediate polars.Comment: Accepted for publication in MNRAS; 11 pages, 19 figure
A Comparison of Reef Fish Assemblages on the East and West Sides of Central Eleuthera, Bahamas
Eleuthera is a long, narrow crescent-shaped Atlantic margin island on the eastern extremity of the Great Bahama Bank in the central Bahamas. It is 144 km long and less than 5 km at its greatest width. Fringing reefs with substantial vertical relief (to 5 m in depths of 6 m) are found approximately 500 m offshore on the eastern side of the island facing the Atlantic Ocean. The western side of the island has stretches of rock cliffs and large fallen boulders providing substrate with similar vertical relief. No open passes exist between the two sides of the island and thus no direct larval transport from one side to the other appears possible. We compared post-settlement fish assemblages and larval supply on either side of central Eleuthera near Governor’s Harbour quarterly from July 2003 until July 2004. Twelve point-counts were performed at two replicate sites on both sides of the island to census juveniles and adults. Abundance, as well as average, maximum and minimum lengths of species present were recorded. Three light traps were moored at each of the same sites 40-50 m from the reef for three to five nights around the new moon to examine larval supply. Fish collected in the light traps were preserved and transported to the lab. They were identified, enumerated, and standard length was measured. Preliminary analyses of point-count and light trap data indicate dissimilar assemblage structure between the two sides of the island, with significantly greater fish abundance and species richness on the eastern side
1RXS J232953.9+062814: A Dwarf Nova with a 64-minute Orbital Period and a Conspicuous Secondary Star
We present spectroscopy and time-series photometry of the newly discovered
dwarf nova 1RXS J232953.9+062814. Photometry in superoutburst reveals a
superhump with a period of 66.06(6) minutes. The low state spectrum shows
Balmer and HeI emission on a blue continuum, and in addition shows a rich
absorption spectrum of type K4 +- 2. The absorption velocity is modulated
sinusoidally at P_orb = 64.176(5) min, with semi-amplitude K = 348(4) km/s. The
low-state light curve is double-humped at this period, and phased as expected
for ellipsoidal variations. The absorption strength does not vary appreciably
around the orbit. The orbital period is shorter than any other cataclysmic
variable save for a handful of helium-star systems and V485 Centauri (59
minutes). The secondary is much hotter than main sequence stars of similar
mass, but is well-matched by helium-enriched models, indicating that the
secondary evolved from a more massive progenitor. A preliminary calculation in
which a 1.2 solar-mass star begins mass transfer near the end of H burning
matches this system's characteristics remarkably well.Comment: accepted to Astrophysical Journal Letters; 14 pages, 3 eps figures +
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A Hierarchical Model of Virtual Experience and Its Influences on the Perceived Value and Loyalty of Customers
Many businesses use virtual experience (VE) to enhance the overall customer experience, though extant research offers little guidance for how to improve consumers’ VE. This study, anchored in activity theory, examines key drivers of VE and its influences on value perceptions and customer loyalty. A hierarchical model indicates that VE comprises second-order variables (i.e., social presence, social capital, flow experience, and situational involvement) and third-order variables (i.e., communal and individual experience). The results obtained from a substantive model further reveal that VE positively influences perceptions of both economic and social value and thus influences loyalty in both the real world and virtual environments
Search for the electric dipole moment of the electron with thorium monoxide
The electric dipole moment of the electron (eEDM) is a signature of
CP-violating physics beyond the Standard Model. We describe an ongoing
experiment to measure or set improved limits to the eEDM, using a cold beam of
thorium monoxide (ThO) molecules. The metastable state in ThO
has important advantages for such an experiment. We argue that the statistical
uncertainty of an eEDM measurement could be improved by as much as 3 orders of
magnitude compared to the current experimental limit, in a first-generation
apparatus using a cold ThO beam. We describe our measurements of the state
lifetime and the production of ThO molecules in a beam, which provide crucial
data for the eEDM sensitivity estimate. ThO also has ideal properties for the
rejection of a number of known systematic errors; these properties and their
implications are described.Comment: v2: Equation (11) correcte
An XMM-Newton observation of the nova-like variable UX UMa: spatially and spectrally resolved two-component X-ray emission
In the optical and ultraviolet regions of the electromagnetic spectrum, UX
Ursae Majoris is a deeply eclipsing cataclysmic variable. However, no soft
X-ray eclipse was detected in ROSAT observations. We have obtained a 38 ksec
XMM-Newton observation to further constrain the origin of the X-rays. The
combination of spectral and timing information allows us to identify two
components in the X-ray emission of the system. The soft component, dominant
below photon energies of 2 keV, can be fitted with a multi-temperature plasma
model and is uneclipsed. The hard component, dominant above 3 keV, can be
fitted with a kT ~ 5 keV plasma model and appears to be deeply eclipsed. We
suggest that the most likely source of the hard X-ray emission in UX UMa, and
other systems in high mass transfer states, is the boundary layer.Comment: To appear in MNRAS Letter
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