Optimal operating conditions for external cavity semiconductor laser optical chaos communication system

In this study, we have proposed and numerically demonstrated that the bias current of a semiconductor laser cannot be used as a key for optical chaos communication, using external-cavity lasers. This is because the chaotic carrier has a signature of relaxation oscillation, whose period can be extracted by the first side peak of the carrier’s autocorrelation function. Then, the bias current can be approximately cracked, according to the well-known relationship between the bias current and relaxation period of a solitary laser. Our simulated results have shown that the cracked current eavesdropper could successfully crack an encrypted message, by means of a unidirectional locking injection or a bidirectional coupling. In addition, the cracked bias current was closer to the real value as the bias current increased, meaning that a large bias current brought a big risk to the security.

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ENSURING OPTIMAL OPERATING CONDITIONS OF THE PRODUCTIVE FORMATION TO ACHIEVE THE MAXIMUM OPERATION OF OIL RESERVES OF THE FIELD OF BESBOLEK

International scientific journal Internauka ◽

10.25313/2520-2057-2020-4-5710 ◽

2016 ◽

Author(s):

Gulnaz Moldabaeva ◽

◽

Reichan Suleimenova ◽

Akmaral Karimova ◽

Nurlybek Shugaepov ◽

...

Keyword(s):

Operating Conditions ◽

Optimal Operating ◽

Oil Reserves

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Studies of microbial acclimation to hard chemicals on the basis of respiratory quinone profiles and kinetic analyses

Water Science & Technology ◽

10.2166/wst.1996.0557 ◽

1996 ◽

Vol 34 (5-6) ◽

pp. 249-256 ◽

Cited By ~ 4

Author(s):

Hong-Ying Hu ◽

Mamie Nozawa ◽

Koichi Fujie ◽

Tsuyoshi Makabe ◽

Kohei Urano

Keyword(s):

Pseudomonas Aeruginosa ◽

Population Dynamics ◽

Volatile Substance ◽

Operating Conditions ◽

Biological Wastewater Treatment ◽

Basic Information ◽

Optimal Operating ◽

Respiratory Quinone ◽

Treatment Processes ◽

Quinone Profile

The population dynamics of microbes in the biological wastewater treatment processes such as a submerged biofilter was investigated to obtain basic information to determine the optimal operating conditions. The effects of coexistence of biodegradable substances such as glucose and peptone on the acclimation of microbes in the biofilm to hard chemicals such as acrylonitrile (AN), which is poorly biodegradable and a volatile substance, was investigated on the basis of the respiratory quinone profile. Kinetic study of the removal of AN in the course of acclimation of microbes was investigated using a laboratory-scale submerged biofilter as well. It was ascertained that the acclimation of the microbes to AN was accelerated by coexistence of biodegradable substances, and the microbial phase after acclimation differed from those with the coexistence of glucose and peptone. The quinone profiles in the acclimation showed that Brevibacterium sp. and Pseudomonas aeruginosa, of which the predominant quinone of the respiratory chain is menaquinone-8(H2) and ubiquinone-9, respectively, multiplied selectively in the acclimation course without and with the coexistence of glucose and peptone, respectively. It was also made clear that there were few kinds and number of protozoa and metazoa in the biofilter treating the wastewater containing AN.

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