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Host Residentsā Perceptions and Attitudes toward an Event
This study investigates the structural relationship among perceived impacts, benefit perceptions, and supports for the event. Local residents in the Black Hills area in South Dakota, where the Sturgis Motorcycle Rally is held, were invited to participate in the study. A total of 190 responses were collected using convenience sampling and structural equation modeling was performed to identify the relationship. The findings indicate that the perceived positive impact significantly affects both benefit perceptions and supports while perceived negative impact is not a significant predictor of residentsā benefit perception. In order to maximize community supports, it is recommended that event organizers emphasize on positive economic impacts
Real-time delay-multiply-and-sum beamforming with coherence factor for in vivo clinical photoacoustic imaging of humans
In the clinical photoacoustic (PA) imaging, ultrasound (US) array transducers are typically used to provide B-mode images in real-time. To form a B-mode image, delay-and-sum (DAS) beamforming algorithm is the most commonly used algorithm because of its ease of implementation. However, this algorithm suffers from low image resolution and low contrast drawbacks. To address this issue, delay-multiply-and-sum (DMAS) beamforming algorithm has been developed to provide enhanced image quality with higher contrast, and narrower main lobe compared but has limitations on the imaging speed for clinical applications. In this paper, we present an enhanced real-time DMAS algorithm with modified coherence factor (CF) for clinical PA imaging of humans in vivo. Our algorithm improves the lateral resolution and signal-to-noise ratio (SNR) of original DMAS beam-former by suppressing the background noise and side lobes using the coherence of received signals. We optimized the computations of the proposed DMAS with CF (DMAS-CF) to achieve real-time frame rate imaging on a graphics processing unit (GPU). To evaluate the proposed algorithm, we implemented DAS and DMAS with/without CF on a clinical US/PA imaging system and quantitatively assessed their processing speed and image quality. The processing time to reconstruct one B-mode image using DAS, DAS with CF (DAS-CF), DMAS, and DMAS-CF algorithms was 7.5, 7.6, 11.1, and 11.3 ms, respectively, all achieving the real-time imaging frame rate. In terms of the image quality, the proposed DMAS-CF algorithm improved the lateral resolution and SNR by 55.4% and 93.6 dB, respectively, compared to the DAS algorithm in the phantom imaging experiments. We believe the proposed DMAS-CF algorithm and its real-time implementation contributes significantly to the improvement of imaging quality of clinical US/PA imaging system.11Ysciescopu
Chemically etched ultrahigh-Q wedge-resonator on a silicon chip
Ultrahigh-Q optical resonators are being studied across a wide range of fields, including quantum information, nonlinear optics, cavity optomechanics and telecommunications. Here, we demonstrate a new resonator with a record Q-factor of 875 million for on-chip devices. The fabrication of our device avoids the requirement for a specialized processing step, which in microtoroid resonators8 has made it difficult to control their size and achieve millimetre- and centimetre-scale diameters. Attaining these sizes is important in applications such as microcombs and potentially also in rotation sensing. As an application of size control, stimulated Brillouin lasers incorporating our device are demonstrated. The resonators not only set a new benchmark for the Q-factor on a chip, but also provide, for the first time, full compatibility of this important device class with conventional semiconductor processing. This feature will greatly expand the range of possible āsystem on a chipā functions enabled by ultrahigh-Q devices
A Feasible Configuration of AFDX Networks for Real-Time Flows in Avionics Systems
REACTION 2013. 2nd International Workshop on Real-time and distributed computing in emerging applications. December 3rd, 2013, Vancouver, Canada.AFDX (Avionics Full Duplex Switched Ethernet)
Networks have been proposed to meet unique ADN (Aircraft
Data Networks) characteristics and then standardized as a Part
7 in ARNIC 664. As for this new communication technology, some
research works have been conducted to address design issues such
as optimizing virtual links as well as analytic modeling including
response time. Despite of their research efforts, configuration
problem for both MTU (Maximum Transmission Unit) and BAG
(Bandwidth Allocation Gap) over virtual links in AFDX networks
remains unsolved yet. In this paper, we propose how to set MTU
and BAG value on each virtual link according to both application
requirements and AFDX switch constraints. We define a new
problem of feasible configurations of virtual links in an AFDX
switch and propose an algorithm to derive feasible BAG and MTU
pairs based on the branch-and-bound technique. Throughout
simulations, we evaluate the proposed algorithm and analyze the
effect of parameters in AFDX networks.This research was supported by Basic Science Research
Program through the National Research Foundation of Korea
(NRF) funded by the Ministry of Education (No. NRF-
2012R1A1A1015096) and BK21+ Program
Leveraging Speaker Embeddings with Adversarial Multi-task Learning for Age Group Classification
Recently, researchers have utilized neural network-based speaker embedding
techniques in speaker-recognition tasks to identify speakers accurately.
However, speaker-discriminative embeddings do not always represent speech
features such as age group well. In an embedding model that has been highly
trained to capture speaker traits, the task of age group classification is
closer to speech information leakage. Hence, to improve age group
classification performance, we consider the use of speaker-discriminative
embeddings derived from adversarial multi-task learning to align features and
reduce the domain discrepancy in age subgroups. In addition, we investigated
different types of speaker embeddings to learn and generalize the
domain-invariant representations for age groups. Experimental results on the
VoxCeleb Enrichment dataset verify the effectiveness of our proposed adaptive
adversarial network in multi-objective scenarios and leveraging speaker
embeddings for the domain adaptation task
Highly p-doped graphene obtained by fluorine intercalation
We present a method for decoupling epitaxial graphene grown on SiC(0001) by
intercalation of a layer of fluorine at the interface. The fluorine atoms do
not enter into a covalent bond with graphene, but rather saturate the substrate
Si bonds. This configuration of the fluorine atoms induces a remarkably large
hole density of p \approx 4.5 \times 1013 cm-2, equivalent to the location of
the Fermi level at 0.79 eV above the Dirac point ED .Comment: 4 pages, 2 figures, in print AP
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