6,682 research outputs found
Radiation and Polarization Signatures of 3D Multi-zone Time-dependent Hadronic Blazar Model
We present a newly developed time-dependent three-dimensional multi-zone
hadronic blazar emission model. By coupling a Fokker-Planck based
lepto-hadronic particle evolution code 3DHad with a polarization-dependent
radiation transfer code, 3DPol, we are able to study the time-dependent
radiation and polarization signatures of a hadronic blazar model for the first
time. Our current code is limited to parameter regimes in which the hadronic
-ray output is dominated by proton synchrotron emission, neglecting
pion production. Our results demonstrate that the time-dependent flux and
polarization signatures are generally dominated by the relation between the
synchrotron cooling and the light crossing time scale, which is largely
independent of the exact model parameters. We find that unlike the low-energy
polarization signatures, which can vary rapidly in time, the high-energy
polarization signatures appear stable. As a result, future high-energy
polarimeters may be able to distinguish such signatures from the lower and more
rapidly variable polarization signatures expected in leptonic models.Comment: Accepted for Publication in The Astrophysical Journa
Investment guidance for the Chinese medical device market
The medical device market is one of the most attractive and profitable areas in the global economy. Since China opened its doors to the world it has attracted increasing amounts of foreign investment. The Chinese medical device market is currently one of the most promising and fastest growing markets, which is the second largest market in the world with 200 billion yuan (RMB) total sales in 2013. This paper illustrates the geographical distribution of the Chinese medical device industry, combined with the location quotient (LQ) assessment, to reveal the medical device industry’s professional level and degree of concentration in each province, providing guidance for investors who are interested in medical device investment in China. The LQ and market share (MS) matrix reveals that the best investment regions in China are: Bohai Economic Rim, Yangtze River Delta and Pearl River Delta Economic Zones
Applied Sensor Fault Detection, Identification and Data Reconstruction
Sensor fault detection and identification (SFD/I) has attracted considerable attention in military applications, especially when safety- or mission-critical issues are of paramount importance. Here, two readily implementable approaches for SFD/I are proposed through hierarchical clustering and self-organizing map neural networks. The proposed methodologies are capable of detecting sensor faults from a large group of sensors measuring different physical quantities and achieve SFD/I in a single stage. Furthermore, it is possible to reconstruct the measurements expected from the faulted sensor and thereby facilitate improved unit availability. The efficacy of the proposed approaches is demonstrated through the use of measurements from experimental trials on a gas turbine. Ultimately, the underlying principles are readily transferable to other complex industrial and military systems
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