291 research outputs found
Stable scalable control of soliton propagation in broadband nonlinear optical waveguides
We develop a method for achieving scalable transmission stabilization and
switching of colliding soliton sequences in optical waveguides with
broadband delayed Raman response and narrowband nonlinear gain-loss. We show
that dynamics of soliton amplitudes in -sequence transmission is described
by a generalized -dimensional predator-prey model. Stability and bifurcation
analysis for the predator-prey model are used to obtain simple conditions on
the physical parameters for robust transmission stabilization as well as on-off
and off-on switching of out of soliton sequences. Numerical simulations
for single-waveguide transmission with a system of coupled nonlinear
Schr\"odinger equations with show excellent agreement with the
predator-prey model's predictions and stable propagation over significantly
larger distances compared with other broadband nonlinear single-waveguide
systems. Moreover, stable on-off and off-on switching of multiple soliton
sequences and stable multiple transmission switching events are demonstrated by
the simulations. We discuss the reasons for the robustness and scalability of
transmission stabilization and switching in waveguides with broadband delayed
Raman response and narrowband nonlinear gain-loss, and explain their advantages
compared with other broadband nonlinear waveguides.Comment: 37 pages, 7 figures, Eur. Phys. J. D (accepted
Video Quality Assessment: From 2D to 3D - Challenges and Future Trends
International audienceThree-dimensional (3D) video is gaining a strong momentum both in the cinema and broadcasting industries as it is seen as a technology that will extensively enhance the user's visual experience. One of the major concerns for the wide adoption of such technology is the ability to provide sufficient visual quality, especially if 3D video is to be transmitted over a limited bandwidth for home viewing (i.e. 3DTV). Means to measure perceptual video quality in an accurate and practical way is therefore of highest importance for content providers, service providers, and display manufacturers. This paper discusses recent advances in video quality assessment and the challenges foreseen for 3D video. Both subjective and objective aspects are examined. An outline of ongoing efforts in standards-related bodies is also provided
Evaluation of genetic diversity of Vietnamese dogs based on mitochondrial DNA hypervariable-1 region
Haplogroup E were detected with high frequency in the population of Phu Quoc ridgeback dogs suggesting that this Vietnamese valuable dog breed originated from domestic dogs harbouring haplogroup E from Vietnam’s mainland or from East Asia where the presence of haplogroup E was reported. Evaluation of the genetic diversity of the Vietnam’s mainland dogs and haplogroup Escreening would support us in tracking out the origin of Phu Quoc ridgeback dog
A preliminary study of photometric redshifts based on the Wide Field Survey Telescope
The Wide Field Survey Telescope (WFST) is a dedicated time-domain multi-band
(, , , , and ) photometric survey facility under construction.
In this paper, we present a preliminary study that assesses the quality of
photometric redshifts based on WFST by utilizing mock observations derived with
the galaxy catalog in the COSMOS/UltraVISTA field. We apply the template
fitting technique to estimate photometric redshifts by using the ZEBRA
photometric-redshift code and adopting a modified set of adaptive templates. We
evaluate the bias (median relative offset between the output photometric
redshifts and input redshifts), normalized median absolute deviation
() and outlier fraction () of photometric
redshifts in two typical WFST observational cases, the single 30-second
exposure observations (hereafter shallow mode) and co-added 50-minute exposure
observations (hereafter deep mode). We find bias\la0.006, \sigma_{\rm
NMAD}\la0.03, and f_{\rm outlier}\la5\% in the shallow mode and bias, , and -- in the deep mode, respectively, under various lunar phases.
Combining the WFST mock observational data with that from the upcoming CSST and
Euclid surveys, we demonstrate that the results can be
significantly improved, with and .Comment: 20 pages, 13 figures. Accepted for publication in Research in
Astronomy and Astrophysics (RAA
An Empirical Research on Customers’ Awareness of E-Commerce in the Context of Vietnamese Developing Economies
Many research studies have been conducted in the field of e-commerce, which can contribute for academic background and development of e-commerce around the world. In Vietnam, the awareness of customers toward e-commerce is limited for the emerging of this industry in Vietnam recently. This study tries to figure out research model explains the factors and to study the awareness of customers that influence the behaviors and acceptance of users buying online in the developing economy. According to the research, buying online is quite risky. Therefore, product safety would be the purchasing decision's priority. Online sales providers need to provide a safe way of ensuring consumers ' purchasing process. Through hard qualification process, they need to shortlist the good quality product. The sale would grow dramatically as consumers gained confidence. Not only should they care about the short-term profit in order to get the products of low quality
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