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Abstract

The purpose of the paper is the attempt to point one of the most important aspects of the cultural contact of the Poland and Arabic countries with the consideration of the historical perspective. The author assumes that the language is the basic carrier of such contacts and also the main area of the mutual influences. Therefore, she discusses the Arabic and Polish relations mostly on the level of the translation of the literary and scientific output of both sides, as well as the linguistic interference mainly in the aspect of the lexical borrowings. The author quotes many examples of such linguistic contacts and underlines their great meaning in the existence and development of other types of relations: political, commercial, and cultural.

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Authors and Affiliations

Elżbieta Górska
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Abstract

The subject of the article are personal names of the Ukrainian population living in the former Chełm land, presented within the context of historical and cultural and religious conditions, as determinants of national identity. Language, in addition to tradition, a sense of religious, historical and territorial community and national consciousness, being one of its basic elements. Shown is the relationship between certain types of anthroponyms and their linguistic structure together with their ethnic and social origin and, to some extent, the system of values professed. Attention has also been paid to the phenomenon of the infiltration of Polish features present in the anthroponymy of the inhabitants of the area in question.

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Authors and Affiliations

Irena Mytnik
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Abstract

The Polish Academy of Sciences asks prominent experts about the problem with bark beetle outbreaks in the Białowieża Primeval Forest. Should the protection of this ancient forest include felling and removing infected trees?

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Authors and Affiliations

Zbigniew Mirek
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Abstract

Weed competition in southern Brazil is one of the main limiting factors for Oryza sativa L. (flooded rice) yield. Echinochloa spp. (barnyardgrass) occurs at a high frequency. Although the potential for weed interference in this cereal is well known, there is little information available about the impact of nutrient competition on rice. Thus, this study aimed to evaluate the relationship between the increase of the barnyardgrass population and the development and nutrition of flooded rice plants at different stages of development. The treatments consisted of growing populations of barnyardgrass competing with the crop from stage V4, which were: 0, 1, 6, 13, 100 and 200 plants · m−2. The experimental design was randomized blocks with two replications, and the experimental units were plots 1.53 m wide by 5 m long. Plant biomass, nutrient uptake and loss of productivity were determined with three replications. An increase in the barnyardgrass population reduced the dry mass of rice leaves and stems, regardless of the evaluation period and the vegetative or reproductive period. Barnyardgrass plants had a significant impact on the reduced grain yield of a flooded rice crop, mainly due to high nutrient competitiveness, especially N in the vegetative period and K in the reproductive period. Barnyardgrass caused a loss of yield by unit · m−2 of 1.13%. The competition for N between rice and barnyardgrass plants was higher in the vegetative period, while for K, Ca and Mg the highest competition occurred in the reproductive period.

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Authors and Affiliations

André da Rosa Ulguim
Roberto Avila Neto
Filipe Selau Carlos
Nereu Augusto Streck
Gean Leonardo Richter
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Abstract

A contactless laser hygrometer based on light absorption by H2O molecules at 1392.5 nm is described. However, measurement results can be affected by optical noise when applied to an atmospheric tunnel or glass cuvette. The noises (occurring in the form of periodic fringes in the recorded spectrum) come from unexpected interference of the light beams reflected from surfaces of the windows or other optical elements. The method of their suppression is described in this article. It is based on wavelength modulation and signal averaging over the fringes period. Also, an experiment confirming the usefulness of this method is described here.
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Authors and Affiliations

Tadeusz Stacewicz
1
Mateusz Winkowski
1
Natalia Kuk
1

  1. Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-093 Warsaw, Pasteura 5, Poland
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Abstract

The aim of the article is to present loan vocabulary connected to clothes and ornaments. The Old-Believers’ dialect is subject to Polish interference on the lexical level because vocabulary is the linguistic element which is changing most rapidly. The dialect studied is situated in the Polish linguistic environment and thus it is isolated due to its lack of territorial contact with the Russian language. It belongs to the so-called Pskov group – the western Central Great Russian akanie dialects. Since the 1950s, when research into the dialect was initiated by Iryda Grek-Pabisowa and Irena Maryniakowa, the biggest increase in loan words has been noticed in the vocabulary related to health, jobs, clothes and ornaments, and the expressions used to refer to the new reality: the progress of civilisation, education, transport and agriculture. The lexemes borrowed are subject to various adaptation processes, for example, phonetic, stress-pattern, morphological or derivational ones.

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Authors and Affiliations

Dorota Paśko-Koneczniak
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Abstract

GNSS systems are susceptible to radio interference despite then operating in a spread spectrum. The commerce jammers power up to 2 watts that can block the receiver function at a distance of up to 15 kilometers in free space. Two original methods for GNSS receiver testing were developed. The first method is based on the usage of a GNSS simulator for generation of the satellite signals and a vector signal RF generator for generating different types of interference signals. The second software radio method is based on a software GNSS simulator and a signal processing in Matlab. The receivers were tested for narrowband CW interference, FM modulated signal and chirp jamming signals and scenarios. The signal to noise ratio usually drops down to 27 dBc-Hz while the jamming to signal ratio is different for different types of interference. The chirp signal is very effective. The jammer signal is well propagated in free space while in the real mobile urban and suburban environment it is usually strongly attenuated.

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Authors and Affiliations

Tomáš Morong
Pavel Puričer
Pavel Kovář
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Abstract

Cloud radio access network (C-RAN) has been proposed as a solution to reducing the huge cost of network upgrade while providing the spectral and energy efficiency needed for the new generation cellular networks. In order to reduce the interference that occur in C-RAN and maximize throughput, this paper proposes a sequentially distributed coalition formation (SDCF) game in which players, in this case the remote radio heads (RRHs), can sequentially join multiple coalitions to maximize their throughput. Contrary to overlapping coalition formation (OCF) game where players contribute fractions of their limited resources to different coalitions, the SDCF game offers better stability by allowing sequential coalition formation depending on the availability of resources and therefore providing a balance between efficient spectrum use and interference management. An algorithm for the proposed model is developed based on the merge-only method. The performance of the proposed algorithm in terms of stability, complexity and convergence to final coalition structure is also investigated. Simulation results show that the proposed SDCF game did not only maximize the throughput in the C-RAN, but it also shows better performances and larger capabilities to manage interference with increasing number of RRHs compared to existing methods.

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Authors and Affiliations

Abiodun Gbenga-Ilori
Olufunmilayo Sanusi
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Abstract

Detailed studies on the effects of pulsed laser interference heating on surface characteristics and subsurface microstructure of amorphous Fe80Si11B9 alloy are reported. Laser interference heating, with relatively low pulsed laser energy (90 and 120 mJ), but with a variable number (from 50-500) of consecutive laser pulses permitted to get energy accumulation in heated areas. Such treatment allowed to form two- Dimensional micro-islands of laser-affected material periodically distributed in amorphous matrix. The crystallization process of amorphous FeSiB ribbons was studied by means of scanning and transmission electron microscopy. Detailed microstructural examination showed that the use of laser beam, resulted in development of nanostructure in the heated areas of the amorphous ribbon. The generation of nanocrystalline seed islands created by pulsed laser interference was observed. This key result may evidently give new knowledge concerning the differences in microstructure formed during the conventional and lased induced crystallization the amorphous alloys. Further experiments are needed to clarify the effect of pulsed laser interference crystallization on magnetic properties of these alloys.
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Authors and Affiliations

J. Morgiel
R. Ostrowski
J. Kusiński
O. Czyż
A. Radziszewska
M. Strzelec
C. Czyż
A. Rycyk
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Abstract

The paper presents the results of research on the plastic zones formation in thin (3.51 [mm]) shields made of steel C45 with holes of 4, 10 and 20 diameters. The authorship method of identifying plastic macro-strains utilizing optical interference phenomenon was used in the experiments. The basic idea of the method is summarized below as being: “The occurrence of plastic deformations in the active process of loading is testified by a loss of the interference fringes that were previously present or by a clear and rapid change in their character”. In the experiments, the values of the stress initiating the first plastic deformation were determined. In order to explain the processes of plastic deformation appearance a detailed stress state analysis in the holes surrounding area was realized with the use of Finite Element Method. Comparison of experimental results with the results of FEM calculations indicates that there are significant quantitative as well as qualitative differences. Namely stresses initiating plastic deformations clearly exceed the value of ReH, and plastic deformation are of local plastic slides character. Similar results were previously obtained in studies on the shields made of steel 15CrMo with holes.

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Authors and Affiliations

Stefan Bućko
Henryk Jodłowski
Marcin Trzebicki
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Abstract

The issue of linguistic interference will be analysed from the point of view of medical translations in the Italian-Polish linguistic pair. Since linguistic interference can manifest itself at almost all levels of the text (phonetic, orthographic, morphological, syntactic, socio-cultural), with the analysis of the fragments taken from translated medical documents we would like to understand which are the most frequent cases of the phenomenon when it comes to translated medical texts and which factors favour the interference most.
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Authors and Affiliations

Katarzyna Maniowska
1

  1. Università Marie Curie-Skłodowska
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Abstract

This study was conducted to predict the yield and biomass of lentil (Lens culinaris L.) affected by weeds using artificial neural network and multiple regression models. Systematic sampling was done at 184 sampling points at the 8-leaf to early-flowering and at lentil maturity. The weed density and height as well as canopy cover of the weeds and lentil were measured in the first sampling stage. In addition, weed species richness, diversity and evenness were calculated. The measured variables in the first sampling stage were considered as predictive variables. In the second sampling stage, lentil yield and biomass dry weight were recorded at the same sampling points as the first sampling stage. The lentil yield and biomass were considered as dependent variables. The model input data included the total raw and standardized variables of the first sampling stage, as well as the raw and standardized variables with a significant relationship to the lentil yield and biomass extracted from stepwise regression and correlation methods. The results showed that neural network prediction accuracy was significantly more than multiple regression. The best network in predicting yield of lentil was the principal component analysis network (PCA), made from total standardized data, with a correlation coefficient of 80% and normalized root mean square error of 5.85%. These values in the best network (a PCA neural network made from standardized data with significant relationship to lentil biomass) were 79% and 11.36% for lentil biomass prediction, respectively. Our results generally showed that the neural network approach could be used effectively in lentil yield prediction under weed interference conditions.

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Authors and Affiliations

Alireza Bagheri
Negin Zargarian
Farzad Mondani
Iraj Nosratti
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Abstract

Most automotive electronic components can cause electromagnetic interference, that can cause power electronic circuits to become unstable. As per electromagnetic compatibility (EMC) standards, these electronic circuits should meet the specifications which are not achieved under some conditions. In this paper, the conducted emissions (CEs) are generated due to the switching of a buck converter, which often occurs in automotive electronics. The noise source was found to be due to the presence of common mode currents which largely affects the performance of EMC. Two types of filtering techniques were analysed and designed, and the results were compared to find an effective filtering solution to mitigate the effects of CE due to a common mode noise for the frequency range from 150 kHz to 108 MHz according to the International Special Committee on Radio Interference (CISPR25) standard. The capacitive and parasitic impedance were calculated and then used in the simulation. Finally, the simulated and measured results are presented. The noise level can be minimized by as much as 50 dB, which is an efficient noise reduction value.
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Authors and Affiliations

G. V. Aswini
1
ORCID: ORCID
S. Chenthurpandian
1

  1. Department of Electronics and Communication Engineering, SNS College of Technology, Coimbatore-641035, India
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Abstract

The paper presents issues associated with the impact of electromagnetic interference on track-side cabinets of a closed-circuit television system (CCTV) functioning in a railway transport environment. The measurements of an electromagnetic field emitted by a track-side CCTV cabinet were presented. Designs of this kind are operated in railway facilities; therefore, they should not disturb the functioning of other equipment, the rail traffic control systems, in particular (so-called inner compatibility). An analysis of the obtained results enabled developing a research model, and a further reliability and operational analysis, taking into account electromagnetic interference. This enabled determining a relationship allowing the determination of the probability of a track-side CCTV cabinet staying in a state of full ability. The presented discussions regarding a track-side CCTV cabinet, taking into account electromagnetic interference, allow for the numerical assessment of different types of solutions (technical and organizational), which can be implemented in order to mitigate the impact of electromagnetic interference on a system’s functioning.
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Authors and Affiliations

Jacek Paś
1
ORCID: ORCID
Adam Rosiński
2
ORCID: ORCID
Kamil Białek
3
ORCID: ORCID

  1. Military University of Technology, ul. gen. S. Kaliskiego 2, 00-908 Warsaw, Poland
  2. Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warsaw, Poland
  3. Railway Institute, ul. Chłopickiego 50, 04-275 Warsaw, Poland
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Abstract

The direct motivation for this article is the publication of two updates of the Polish Journal Rankings on 9 and 18 February 2021, which were prepared by the Minister of Education and Science and bypassed the Research Evaluation Commission. This article aims to characterize the changes made by the minister in relation to the draft ranking prepared by the commission. For providing a complete picture of the changes, I describe the main principles for building the ranking according to the new model implemented in 2018. Then, I characterize the minister's changes in terms of added journals and changing the points assigned to the journals. The analysis is provided through the lens of the universities publishing these journals and the disciplines assigned to the journals. The article concludes by identifying four main recommendations that should be implemented to restore the usefulness of the ranking as an instrument of science policy.
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Authors and Affiliations

Emanuel Kulczycki
1 2

  1. Pracownia Komunikacji Naukowej na Uniwersytecie im. Adama Mickiewicza w Poznaniu
  2. Komisja Ewaluacji Nauki
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Abstract

A novel method to improve the performance of the frequency band is cognitive radio that was introduced in 1999. Due to a lot of advantages of the OFDM, adaptive OFDM method, this technique is used in cognitive radio (CR) systems, widely. In adaptive OFDM, transmission rate and power of subcarriers are allocated based on the channel variations to improve the system performance. This paper investigates adaptive resource allocation in the CR systems that are used OFDM technique to transmit data. The aim of this paper is to maximize the achievable transmission rate for the CR system by considering the interference constraint. Although secondary users can be aware form channel information between each other, but in some wireless standards, it is impossible for secondary user to be aware from channel information between itself and a primary user. Therefore, due to practical limitation, statistical interference channel is considered in this paper. This paper introduces a novel suboptimal power allocation algorithm. Also, this paper introduces a novel bit loading algorithm. In the numerical results sections, the performance of our algorithm is compared by optimal and conventional algorithms. Numerical results indicate our algorithm has better performance than conventional algorithms while its complexity is less than optimal algorithm.

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Authors and Affiliations

Shirin Razmi
Naser Parhizgar
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Abstract

Orthogonal frequency division multiple access (OFDMA) in Long Term Evolution (LTE) can effectively eliminate intra-cell interferences between the subcarriers in a single serving cell. But, there is more critical issue that, OFDMA cannot accomplish to decrease the inter-cell interference. In our proposed method, we aimed to increase signal to interference plus noise ratio (SINR) by dividing the cells as cell center and cell edge. While decreasing the interference between cells, we also aimed to increase overall system throughput. For this reason, we proposed a dynamic resource allocation technique that is called Experience-Based Dynamic Soft Frequency Reuse (EBDSFR). We compared our proposed scheme with different resource allocation schemes that are Dynamic Inter-cellular Bandwidth Fair Sharing FFR (FFRDIBFS) and Dynamic Inter-cellular Bandwidth Fair Sharing Reuse-3 (Reuse3DIBFS). Simulation results indicate that, proposed EBDSFR benefits from overall cell throughput and obtains higher user fairness than the reference schemes.

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Authors and Affiliations

Mert Yağcıoğlu
Oğuz Bayat
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Abstract

Non-Orthogonal Multiple Access (NOMA) with Successive Interference Cancellation (SIC) is one of the promising techniques proposed for 5G systems. It allows multiple users with different channel coefficients to share the same (time/frequency) resources by allocating several levels of (power/code) to them. In this article, a design of a cooperative scheme for the uplink NOMA Wi-Fi transmission (according to IEEE 802.11 standards) is investigated. Various channel models are exploited to examine the system throughput. Convolutional coding in conformance to IEEE 802.11a/g is applied to evaluate the system performance. The simulation results have been addressed to give a clear picture of the performance of the investigated system.

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Authors and Affiliations

Hind Salim Ghazi
Krzysztof Wesołowski
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Abstract

Unconventional oil and gas reservoirs are characterised by low porosity, low permeability and low natural deliverability. At present, horizontal wells staged fracturing is an effective development method. However, in the case of staged hydraulic fracturing in horizontal wells, stress interference occurs between multiple fractures, leading to fracture deformation and even inhibiting the formation of fractures, thereby affecting reservoir production. In this paper, based on the extended finite element method (XFEM), considering the fluid flow in the fracture and fracturing fluid filtration, we analyse the effects of fracturing fluid pumping rate, fracture spacing and elastic modulus on horizontal in-situ stress, fracture parameters and fracture extension pattern during different fracturing initiation processes. The results show that the induced stress generated by the action of fracturing fluid changes the direction of horizontal in-situ stress in the elliptical region around the fracture. In the mode of simultaneous fracture initiation (TFIS), the extension of two symmetrical fractures is “repulsive”; in the mode of two fractures initiated at different times (TFIDT), the extension direction is “mutual attraction”. A large pumping rate and small elastic modulus are conducive to fracture propagation. In the TFIS mode, two fractures alternately expand, while in the TFIDT mode, the impact of rock mechanical properties and construction parameters on fracture propagation will be amplified. The extension of subsequent fractures will be restrained, especially when the fracture spacing is less than 10 m. The width of the previously created fracture will be severely affected, even causing a partial closure and becoming elongated fractures.
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Authors and Affiliations

Shuang Liang
1 2 3
ORCID: ORCID
Di Wang
1 2
ORCID: ORCID
Dan Liu
4
Yang Tian
3
ORCID: ORCID
Haibo Wang
1 2
ORCID: ORCID
Fengxia Li
1 2
ORCID: ORCID
Gang Dong
5
ORCID: ORCID
Chengfeng Yin
6
ORCID: ORCID
Yi Yang
7
ORCID: ORCID

  1. State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing, China
  2. State Energy Center for Shale Oil Research and Development, Beijing, China
  3. Department of Petroleum Engineering, Northeast Petroleum University, Daqing, China
  4. PipeChina Oil & Gas Pipeline Control Center, Beijing, 122000, China
  5. The Eighth Oil Production Plant of Daqing Oilfield Limited Company, Daqing, China
  6. The Fourth Oil Production Plant of Daqing Oilfield Limited Company, Daqing, China
  7. The Tenth Oil Production Plant of Daqing Oilfield Limited Company, Daqing, China
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Abstract

Nowadays, the Polish Old Believers live in a language island. Language islands are detached from their ethnolinguistic roots and suffer a constant shortage of language structures. On the one hand, they acquire the language of the dominant group; on the other hand, it is important for them to preserve the language of their ancestors. The Old Believers’ Russian dialect has been influenced by the Polish language for over a century. As a result of the territorial proximity of the Old Believers’ homeland with the compact Belarusian language territory as well as exposure to Belarusian language and its dialects, “Polish” Old Believers’ speech bears many features characteristic for them. The main aim of this paper is to present the prepositions of space in the local dialect of Old Believers in Poland and to describe their characteristics. The “Polish” Old Believers’ narratives investigated in this paper contain many examples of use of the prepositions of space typical for their indigenous dialects as well as the Belarusian language and dialects. There are also many examples of use of such prepositions that can be considered as a result of Polish influence on the Russian dialect of Old Believers living in Poland.

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Authors and Affiliations

Adam Jaskólski
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Abstract

Specific requirements are designed and implemented in electronic and telecommunication systems for received signals, especially high-frequency ones, to examine and control the signal radiation. However, as a serious drawback, no special requirements are considered for the transmitted signals from a subsystem. Different industries have always been struggling with electromagnetic interferences affecting their electronic and telecommunication systems and imposing significant costs. It is thus necessary to specifically investigate this problem as every device is continuously exposed to interferences. Signal processing allows for the decomposition of a signal to its different components to simulate each component. Radiation control has its specific complexities in systems, requiring necessary measures from the very beginning of the design. This study attempted to determine the highest radiation from a subsystem by estimating the radiation fields. The study goal was to investigate the level of radiations received and transmitted from the adjacent systems, respectively, and present methods for control and eliminate the existing radiations.

The proposed approach employs an algorithm which is based on multi-component signals, defect, and the radiation shield used in the subsystem. The algorithm flowchart focuses on the separation and of signal components and electromagnetic interference reduction. In this algorithm, the detection process is carried out at the bounds of each component, after which the separation process is performed in the vicinity of the different bounds. The proposed method works based on the Fourier transform of impulse functions for signal components decomposition that was employed to develop an algorithm for separation of the components of the signals input to the subsystem.

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Authors and Affiliations

Milad Daneshvar
Naser Parhizgar
Homayoon Oraizi
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Abstract

Controlling and reducing the radiation emitted by various systems helps the board designer improve systems’ performance. One proposed way to achieve these goals is to use an algorithm to control the radiation applied to systems. According to the executive structure of the algorithm and considering the nature of the existing signals in several components, the separation of the signal components is on the agenda of the algorithm. In fact, the goal is to create an intuitive view of the multi-component signals around the systems that enter the systems from different angles and have a detrimental effect on their performance. Using signal processing methods, we will be able to break down the signal into different components and simulate each component separately. To prevent high computational repetitions and increase simulation time in signal component analysis, by reducing the components, we reduce the number of mesh cells in the software and, using linear approximation, determine the exact position of the radiation signal applied to systems and thus the best linear relationship. The signal entry path is used to apply the rules required for prediction design.

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Authors and Affiliations

Milad Daneshvar
Nasser Parhizgar
Homayoon Oraizi
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Abstract

Filter bank multicarrier waveform is investigated as a potential waveform for visible light communication broadcasting systems. Imaginary inter-carrier and/or inter-symbol interference are causing substantial performance degradation in the filter bank multicarrier system. Direct current-biased optical filter bank multicarrier modulation overcomes all the problems of direct current-biased optical-orthogonal frequency division multiplexing modulation approaches in terms of speed and bandwidth. However, it also wastes a lot of energy while transforming a true bipolar signal into a positive unipolar signal by adding direct current-bias. In this paper, a flip-filter bank multicarrier-based visible light communication system was introduced to overcome this problem. In this system, a bipolar signal is converted to a unipolar signal by isolating the positive and negative parts, turning them to positive and then delivering the signal. Also, a new channel estimation scheme for a flip-filter bank multicarrier system is proposed which improves the channel estimation performance compared to that of each of the conventional schemes. The proposed system performance is measured in terms of bit error rate, normalized mean squared error, and constellation diagram. The superiority of the proposed scheme over other conventional structures has been successfully verified by MATLAB 2020b simulation experiments results. These results are evaluated under indoor visible light communication standard.
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Bibliography

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Authors and Affiliations

Mohamed Y. El-Ganiny
1
Ashraf A. M. Khalaf
2
ORCID: ORCID
Aziza I. Hussein
3
ORCID: ORCID
Hesham F. A. Hamed
4

  1. Department of Electrical Engineering, Higher Technological Institute, 10th of Ramadan City, Sharqia, Egypt
  2. Department of Electrical Engineering, Faculty of Engineering, Minia University, Minia, Egypt
  3. Electrical and Computer Engineering Department, Effat University, Jeddah, Kingdom of Saudi Arabia
  4. Department of Telecommunications Engineering, Egyptian Russian University, Badr City, Egypt
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Abstract

The design and performance analysis of a 1310/1550-nm wavelength division demultiplexer with tapered geometry based on InP/InGaAsP multimode interference (MMI) coupler has been carried out. Wavelength response of demultiplexer of conventional MMI and tapered input and tapered output (tapered I/O) waveguides geometry of the MMI have been discussed. The demultiplexing function has been first performed by choosing a suitable refractive index of the guiding region and geometrical parameters such as the width and length of MMI structure have been achieved. Access width of tapered I/O waveguides have been adjusted to give a low insertion loss (IL) and high extinction ratio (ER) for the considered wavelengths of 1310 nm and 1550 nm. The total size of the demultiplexer has been significantly reduced over the existing MMI devices. Numerical simulations with finite difference beam propagation method are applied to design and optimize the operation of the proposed demultiplexer.

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Authors and Affiliations

D. Chack
V. Kumar
S.K. Raghuwanshi

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