7,210 research outputs found
Examining the Role of Semantic Similarity in Online Restaurant Review Evaluations
Both language and image are critical for the grasp of information embedded in online reviews. While a large quantity of research has focused on the role of textual features and visual features separately, the specific role of similarity between textual and visual information in online review evaluations (e.g., review usefulness and review enjoyment) remains unaddressed. Thus, drawing on dual coding theory, this study attempts to investigate the impacts of textual and visual features on review evaluations by employing the Latent Dirichlet Allocation (LDA) topic modeling and Google Vision API’s web detection techniques in the context of online restaurant review (ORR). Moreover, the moderating role of semantic similarity is examined in the relationships between textual/visual features and ORR evaluations. It is believed that this study could provide implications on information comprehension, draw consumer interest, and provide suggestions for restaurant managers to tune levels of review evaluation in a proper manner
Unified Analysis of Internal Flowfield in an Integrated Rocket Ramjet Engine. I: Transition from Rocket Booster to Ramjet Sustainer
Abstract: A comprehensive numerical analysis was conducted to study the internal flow development in an integrated rocket-ramjet (IRR) propulsion system. The study consists of two parts: transition from the rocket booster to the ramjet sustainer and combustion dynamics during ramjet operation. The physical model of concern includes the entire IRR flow path, extending from the leading edge of the inlet center body through the exhaust nozzle. The theoretical formulation is based on the Farve-averaged conservation equations of mass, momentum, energy, and species concentration in axisymmetric coordinates and accommodates finite-rate chemical kinetics and variable thermophysical properties. Turbulence closure is achieved using a low-Reynolds-number k-ɛ two-equation model. The governing equations are solved numerically by means of a finite-volume preconditioned flux-differencing scheme capable of treating a chemically reacting flow over a wide range of Mach numbers. Various important physiochemical processes involved in the transition from the booster to the sustainer phase are investigated systemically. Emphasis is placed on the flow interactions between the inlet diffuser and combustor. The effects of operation timing on the flow evolution, fuel spread, ignition, and flame development are studied
Increasing the Durability of Piezoelectric Impact-based Micro Wind Generator in Real Application
AbstractThe purpose of this study is to increase the durability of piezoelectric impact-based micro wind generator (PIMWG) in real application. Using new PIMWG design, numerical simulation, and experimental comparison analysis, we improved the durability of PIMWGs in real application. The experimental results show that the optimized PIMWG generated 2.4 mW (RMS value), and it did not crack within 40h. In this study, we improved the durability of PIMWGs for real application
DISTRIBUTION OF GRIP PRESSURE THROUGHOUT THE PHASES OF PUTTING IN ELITE GOLF COLLEGE PLAYERS
The purpose of this study is to investigate the distribution of grip pressure, force and the peak pressure of different phases during the putting stroke. Five elite college players with handicaps of 2-8 participated in the study. The Novel Pliance-x System and 150Hz 8- camera Motion Analysis Corporation System were used to collect grip pressure and identify each phase of the putting stroke. At each phase of the putting stroke, average grip pressure, peak pressure and grip force were investigated. Results indicated that lowest grip pressure occurred at address up to the top of backswing (2.41±1.36 Kpa). Grip pressure started to increase during the downswing and reached its peak, 0.02±0.05s, before impact (4.70±1.97 Kpa). The pressure reduced again after impact (4.36±2.06 Kpa). Results indicate that grip pressure does not remain the same throughout the stroke
The variation of relative magnetic helicity around major flares
We have investigated the variation of magnetic helicity over a span of
several days around the times of 11 X-class flares which occurred in seven
active regions (NOAA 9672, 10030, 10314, 10486, 10564, 10696, and 10720) using
the magnetograms taken by the Michelson Doppler Imager (MDI) on board the Solar
and Heliospheric Observatory (SOHO). As a major result we found that each of
these major flares was preceded by a significant helicity accumulation over a
long period (0.5 to a few days). Another finding is that the helicity
accumulates at a nearly constant rate and then becomes nearly constant before
the flares. This led us to distinguish the helicity variation into two phases:
a phase of monotonically increasing helicity and the following phase of
relatively constant helicity. As expected, the amount of helicity accumulated
shows a modest correlation with time-integrated soft X-ray flux during flares.
However, the average helicity change rate in the first phase shows even
stronger correlation with the time-integrated soft X-ray flux. We discuss the
physical implications of this result and the possibility that this
characteristic helicity variation pattern can be used as an early warning sign
for solar eruptions
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