510 research outputs found
Computer Technology in Network Society
With the continuous development of society, computer technology hinders all aspects of social life, and information shows an inseparable relationship. With the help of reasonable use of computer technology, the speed of information processing is significantly improved, and the transmission and identification of information are further promoted. The continuous advancement of computer technology has contributed to the rapid expansion of its influence. From the objective point of view, the computer technology in play its advantages at the same time, once the use of unscientific, will also form a certain negative impact. Therefore, it is necessary to discuss the computer technology from many angles
Well-posedness of the discrete nonlinear Schr\"odinger equations and the Klein-Gordon equations
The primary objective of this paper is to investigate the well-posedness
theories associated with the discrete nonlinear Schr\"odinger equation and
Klein-Gordon equation. These theories encompass both local and global
well-posedness, as well as the existence of blowing-up solutions for large and
irregular initial data.
The main results of this paper presented in this paper can be summarized as
follows:
1. Discrete Nonlinear Schr\"odinger Equation: We establish global
well-posedness in spaces for all , regardless of
whether it is in the defocusing or focusing cases.
2. Discrete Klein-Gordon Equation (including Wave Equation): We demonstrate
local well-posedness in spaces for all .
Furthermore, in the defocusing case, we establish global well-posedness in
spaces for any . In contrast, in the focusing
case, we show that solutions with negative energy blow up within a finite time
A Chemical Study of Nine Star-forming Regions with Evidence of Infall Motion
The study of the physical and chemical properties of gas infall motion in the
molecular clumps helps us understand the initial stages of star formation. We
used the FTS wide-sideband mode of the IRAM 30-m telescope to observe nine
infall sources with significant double peaked blue line profile. The
observation frequency range are 83.7 - 91.5 GHz and 99.4 - 107.2 GHz. We have
obtained numbers of molecular line data. Using XCLASS, a total of 7 to 27
different molecules and isotopic transition lines have been identified in these
nine sources, including carbon chain molecules such as CCH, c-C3H2 and HC3N.
According to the radiation transfer model, we estimated the rotation
temperatures and column densities of these sources. Chemical simulations
adopting a physical model of HMSFRs are used to fit the observed molecular
abundances. The comparison shows that most sources are in the early HMPO stage,
with the inner temperature around several ten K
Hardware-in-the-Loop Simulation for Evaluating Communication Impacts on the Wireless-Network-Controlled Robots
More and more robot automation applications have changed to wireless
communication, and network performance has a growing impact on robotic systems.
This study proposes a hardware-in-the-loop (HiL) simulation methodology for
connecting the simulated robot platform to real network devices. This project
seeks to provide robotic engineers and researchers with the capability to
experiment without heavily modifying the original controller and get more
realistic test results that correlate with actual network conditions. We
deployed this HiL simulation system in two common cases for
wireless-network-controlled robotic applications: (1) safe multi-robot
coordination for mobile robots, and (2) human-motion-based teleoperation for
manipulators. The HiL simulation system is deployed and tested under various
network conditions in all circumstances. The experiment results are analyzed
and compared with the previous simulation methods, demonstrating that the
proposed HiL simulation methodology can identify a more reliable communication
impact on robot systems.Comment: 6 pages, 11 figures, to appear in 48th Annual Conference of the
Industrial Electronics Society IECON 2022 Conferenc
Discovery of an old supernova remnant candidate through carbon monoxide line emission
Most old supernova remnants (SNRs) in the Milky Way have not yet been
identified. Considering their large potential number and the sufficient
momentum-energy transfer to the interstellar medium (ISM), they are a key part
of our understanding of the overall role of SNRs in the ISM. Here we report our
discovery of an expanding molecular shell identified by CO line observations,
namely G16.11-0.51. It covers a known SNR, specifically G16.0-0.5, and is
larger in size, i.e. 0.56 deg over 0.20 deg. Based on its spatial and kinematic
structures, weak nonthermal radio-continuum emission, and derived physical
properties, we suggest that it is an old SNR. At a systemic velocity of +41.3
km s^-1, the best estimated kinematic distance of G16.11-0.51 is ~3.2 kpc,
implying its radius of about 15.6 pc. The age of G16.11-0.51 is estimated to be
greater than ~10^5 yr, and, in a dense molecular environment, it has formed
dense and thin shell layers. The kinetic energy of the expanding molecular gas
of G16.11-0.51 is about 6.4x10^49 erg, accounting for approximately six percent
of the initial SN explosion energy. Although old SNRs have essentially become
cold and hard to detect, our discovery suggests that they can be found by
searching for CO line emissions.Comment: 10 pages, 6 figures, 1 table, in production in Astronomy&Astrophyic
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