Enhancing Secrecy Performance for NOMA Systems with Intelligent Reflecting Surface: Analysis and Optimization

Based on a prediction method of the scattered sound pressure, an active control system was proposed in previous work for the three-dimension scattered radiation, where all the relevant simulations and experiments were implemented in three-dimensional free sound field. However, for practical applications, such as the anti-eavesdropping system or the stealth system for submarines, the sound field conditions are usually complex, and the most common case is the one with reflecting surface. It is questionable whether the previous control system is still effective in non-free sound field, or what improvements should be operated to ensure the control effect. In this article, based on the mirror image principle, two methods of calculating the control source strengths are proposed for the scattered radiation control, and numerical simulations with one-channel and multi-channel system are implemented to detect the corresponding control effect. It is seen that the local active control for the scattered radiation is still effective, and the reduction of the sound pressure level as well as the control area is extended with the increasement of the error sensors and control sources.

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Soil and ecological division into districts of the Baikal region

Geodesy and Cartography ◽

10.22389/0016-7126-2018-940-10-54-64 ◽

2018 ◽

Vol 940 (10) ◽

pp. 54-64 ◽

Cited By ~ 1

Author(s):

I.A. Belozertseva ◽

A.A. Sorokovoj

Keyword(s):

Baikal Region ◽

Soil Cover ◽

Soil Formation ◽

Forest Steppe ◽

Leading Role ◽

Soil Cover Structure ◽

Reflecting Surface ◽

Heat And Moisture ◽

Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

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Intelligent reflecting surface enhanced indoor terahertz communication systems

Nano Communication Networks ◽

10.1016/j.nancom.2020.100284 ◽

2020 ◽

Vol 24 ◽

pp. 100284 ◽

Cited By ~ 9

Author(s):

Xinying Ma ◽

Zhi Chen ◽

Wenjie Chen ◽

Yaojia Chi ◽

Zhuoxun Li ◽

...

Keyword(s):

Communication Systems ◽

Surface Enhanced ◽

Terahertz Communication ◽

Reflecting Surface

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Synthesis of N-CNT/TiO2 composites thin films: surface analysis and optoelectronic properties

E3S Web of Conferences ◽

10.1051/e3sconf/202018305002 ◽

2020 ◽

Vol 183 ◽

pp. 05002 ◽

Cited By ~ 1

Author(s):

Hamza Belkhanchi ◽

Younes Ziat ◽

Maryama Hammi ◽

Charaf Laghlimi ◽

Abdelaziz Moutcine ◽

...

Keyword(s):

Thin Films ◽

Surface Analysis ◽

Sol Gel ◽

Careful Analysis ◽

Optoelectronic Properties ◽

Spectroscopic Techniques ◽

Large Area ◽

Visible Absorption ◽

Temperature Solution ◽

Good Agreement

In this study, we have investigated the surface analysis and optoelectronic properties on the synthesis of N-CNT/TiO2 composites thin films, using sol gel method for a dye synthetized solar cell (DSSC) which is found to be simple and economical route. The titanium dioxide based solar cells are an exciting photovoltaic candidate; they are promising for the realization of large area devices. That can be synthetized by room temperature solution processing, with high photoactive performance. In the present work, we stated comparable efficiencies by directing our investigation on obtaining Sol Gel thin films based on N-CNT/TiO2, by dispersing nitrogen (N) doped carbon nanotubes (N-CNTs) powders in titanium tetraisopropoxyde (TTIP). The samples were assessed in terms of optical properties, using UV—visible absorption spectroscopic techniques. After careful analysis of the results, we have concluded that the mentioned route is good and more efficient in terms of optoelectronic properties. The gap of “the neat” 0.00w% N-CNT/TiO2 is of 3eV, which is in a good agreement with similar gap of semiconductors. The incorporated “w%NCNTs” led to diminishing the Eg with increasing N-CNTs amount. These consequences are very encouraging for optoelectronic field.

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