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931.
This paper proposes a switchable wavelength fiber laser (SWFL) based on an arrayed waveguide grating (AWG) and a gain-saturated
reflective semiconductor optical amplifier (RSOA). The SWFL was experimentally implemented in the C- and L-bands. In order
to achieve narrow-linewidth oscillation, the SWFL was driven by bidirectional injection-locked RSOAs. The RSOA was operated
in the gain-saturated region, using gain compression properties to obtain uniform power over a wide bandwidth. Based on this
configuration, we obtained 40 C-band international telecommunication unit (ITU) wavelengths with 100-GHz channel spacing.
The SWFL displayed a narrow 3-dB bandwidth (<0.06 nm), a high and uniform peak power (P
max > 0.22 dB, ΔP
max < 0.26 dB), and a high and uniform side mode suppression ratio (SMSR > 66 dB, ΔSMSR < 1 dB). The peak-power and wavelength
stabilities were ±0.24 dB and ±0.01 nm, respectively, at room temperature over a 1 h period. 相似文献
932.
S. N. Il’in 《Mathematical Notes》2012,91(5-6):782-788
As is well known, every positive idempotent matrix is of rank 1. It is proved that idempotent matrices without zeros have this property over many skew semifields, and all these skew semifields are described. 相似文献
933.
934.
935.
Tae-Wook Kim Seul-Kee Kim Sungkyun Park Kang Hyun Park Jae-Myung Lee 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):145-159
The present study investigated thermal and mechanical characteristics of irradiated polyurethane foams (PUFs) according to the irradiation does under various temperature conditions, including low/cryogenic temperatures. Fourier transform infrared analysis was performed to obtain information on the PUF molecular structure. In addition, Macro- and microstructural investigations were carried out to determine the relationship between thermal and mechanical characteristics and irradiation dose. The test results were quantitatively presented, and it was found that the irradiated PUF has potential for application in industrial structures. 相似文献
936.
Frontispiece: Irreversible Denaturation of Proteins through Aluminum‐Induced Formation of Backbone Ring Structures 下载免费PDF全文
937.
938.
939.
With the consideration of mechanism of prevention and control for the spread of viral diseases, in this paper, we propose two novel virus dynamics models where state feedback control strategies are introduced. The first model incorporates the density of infected cells (or free virus) as control threshold value; we analytically show the existence and orbit stability of positive periodic solution. Theoretical results imply that the density of infected cells (or free virus) can be controlled within an adequate level. The other model determines the control strategies by monitoring the density of uninfected cells when it reaches a risk threshold value. We analytically prove the existence and orbit stability of semi-trivial periodic solution, which show that the viral disease dies out. Numerical simulations are carried out to illustrate the main results. 相似文献