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Abstract

This theoretical work studies a dynamic general equilibrium model with the financial sector in which aggregate activity depends on the conditions of intermediaries' balance sheets. This environment is used to demonstrate the business cycle consequences of changes in competition in the financial industry. On the one hand, a more competitive banking sector is associated with a higher average level of aggregate output. On the other hand, however, a less competitive financial industry increases financial and macroeconomic stability. This trade-off is present both in the short run and in the long run.
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Authors and Affiliations

Paweł Kopiec
1

  1. SGH Warsaw School of Economics
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Abstract

The article provides an overview of the supranational bank resolution regime established under the Single Resolution Mechanism framework. Both the substantive rules governing the resolution process and its procedural requirements are explained. The main focus of the article is the decision-making practice of the Single Resolution Board (SRB), an EU agency responsible for the execution of the resolution framework, which has already intervened in a number of cases in which banks were considered “failing or likely to fail” by the European Central Bank. The article analyses the existing decisions on resolution action in order to establish how the substantive rules on resolution are interpreted by the SRB in its decision-making practice.

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Authors and Affiliations

Maciej Podgórski
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Abstract

After the banking crisis, the European Union (EU) introduced a framework for the restructuring and orderly liquidation of credit institutions. The overarching goal of the new rules is to manage severe banking crisis more efficiently. One of the main pillars of the European bank resolution regime are the powers of the resolution authorities to use resolution tools (sale of business, bridge bank, bad bank and bail-in). However, the question arises whether the implemented toolkit will be sufficient to effectively contain systemic banking crisis. The literature regarding empirical research on the effectiveness of the BRRD tools provides ambiguous conclusions. Therefore, the newly established resolution authorities in the EU were asked to express their opinion about their readiness to combat systemic crisis and the usefulness of the accessible toolkit. The evaluation of the effectiveness of the resolution tools in a systemic crises by the resolution authorities showed that the most effective resolution tool seems to be the bad bank, while bank liquidation was rated as the least appropriate. Nevertheless, the resolution authorities also identified many barriers for all resolution tools that may limit the ability of their implementation and possibly translate into the lower effectiveness of the resolution framework.

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Authors and Affiliations

Magdalena Kozińska
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Abstract

One more time we would like to pay attention of especially of the hydraulic engineer audience to bankfull stage and discharge. Along the paper we show commonly accepted definitions of it and ways of calculations. It is difficult to determine the size of the bankfull flow level, that is why the authors are presenting many selected methods. Some of the methods allow the determination of biotic bankfull flow through the occurrence of zones of vegetation characteristic and based on the observation of the occurrence of ground beetles (e.g. the Woodyer and the Radecki-Pawlik and Skalski methods). Some of the methods – most popular- are using morphometric parameters (e.g. the Williams, the Hey and Thorne, the Gauckler-Manning and finally the Lambor methods).

We believe that the value of bankfull discharge would be accepted as a supporting tool for designers, hydraulics engineers and managers, especially those who care about river channel environment and cooperate with fluvial geomorphologists- and biologists as well as environmental agencies.

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Authors and Affiliations

Artur Radecki-Pawlik
ORCID: ORCID
Tomasz Skalski
Karol Plesiński
Wiktoria Czech
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Abstract

The paper aims at the empirical evaluation of the impact of bank size (as measured by median total assets) on the value relevance of two key accounting variables, i.e. book values of equity and net earnings, in terms of their joint explanatory power in the regression model and the relative responsiveness of bank market values to the changes in those variables. The research is based on the multiple linear regression analysis after controlling for the presence of fixed and random effects. The examined sample covers all domestically-based commercial banks listed on the Warsaw Stock Exchange over the period 1998–2017. The final pooled sample comprises 18 banks and 271 bank-year observations. The findings of the study suggest that the equity investors perceive the joint informational content of book values and earnings of larger banks as more value relevant in comparison to the accounting numbers reported by their smaller peers. The responsiveness of banks’ market values to the changes in each of the explanatory variables seems, however, to be affected by their size in a different way. As expected, book values of equity have turned out to be significantly more informative for smaller banks, whereas the evidence regarding the impact of size on the responsiveness of bank market values to the changes in net earnings is ambiguous. Although larger banks appear to exhibit a higher sensitivity of stock prices to variations in net earnings per share than their smaller peers, the difference between the examined subsamples is not statistically significant.

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Authors and Affiliations

Piotr Bolibok
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Abstract

Inflation targeting is nowadays used by around 40 countries, with each of them tailoring some features of the strategy to its own needs. This holdse specially for deciding on the level of inflation targets. The analysis conducted in the paper aims at identifying factors affecting the choice of the target levels, with macroeconomic, structural and institutional characteristics of the reviewed economies being investigated. The main conclusion is that both backward- and forward-looking models can help to explain how inflation targets are set. Evidently inflation and GDP growth (past and forecast) together within formation on a possibly on going disinflation process are of key importance,but – especially for emerging market economies – also inflation variance and the level of economic development seem to influence the target levels. Moreover,many of the institutional features related, among others, to transparency and accountability of the reviewed central banks, were found significant in the analysis.

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Authors and Affiliations

Joanna Niedźwiedzińska
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Abstract

This study examines whether the lowering interest-rate environment in CEE countries since the early 2000’s increased bank risk-taking behaviour. We employ 6,979 annual observations from the Bankscope database over the period 1997‒2011 and find a positive relationship between bank risk-taking, measured by risk assets, and interest rates. On the contrary, there is a negative relationsh ipbetween non-performing loans and interest rates. These results are robust across a number of different specifications that account,inter alia, for the potential endogeneity of interest rates and/or the dynamics of bank risk. Moreover, we provide evidence that these findings are mainly driven by the banking sector of the Russian Federation rather than that of the rest CEE countries.

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Authors and Affiliations

Georgios P. Kouretas
Chris Tsoumas
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Abstract

We consider fiscal and monetary policy interactions in a monetary unionunder monetary leadership, when the common central bank is concerned with theaverage fiscal stance of the union. We use a static two-country monetary unionmodel to investigate the policy-mix problem under different regimes of non-cooperation, cooperation, and enforced cooperation among fiscal authorities.We find that fiscal policy is unambiguously countercyclical, a feature that ismore pronounced under fiscal policy cooperation. Monetary policy can be eithercountercyclical or procyclical. A central bank concerned about the aggregatefiscal stance is effective in stabilizing output and central budget, but at theexpense of inflation stabilization.

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Authors and Affiliations

Georgios Chortareas
Christos Mavrodimitrakis
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Abstract

The correlations and the influence of the monetary policy pursued by the central banks of developed countries, primarily by the Federal Reserve System (the central bank of the United States), on the economies of developing countries is a subject of research, especially since the outbreak of the last financial crisis. Decisions concerning shifts in attitudes in the monetary policy taken by the monetary authorities of the largest economies, influence investors’ behaviour. Due to globalization and financialization, short-term capital flows occur very quickly and on a significant scale. Argentina is an illustration of the consequences of monetary policy tapering by the FRS for the economy of a developing country. Argentina was supported during the period of disturbances by the International Monetary Fund. Nevertheless, it seems that this solution is insufficient in view of the globalization of the effects of the monetary policy pursued by the economically strongest countries.

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Authors and Affiliations

Ilona Skibińska-Fabrowska
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Abstract

Species and generic composition of nematode communities from the epiphytic mosses in the Left-bank Polesie were studied. Nematodes were extracted by a modified Baermann’s method. A total of 47 species was found and they belonged to 34 genera, 21 families and 8 orders. The average number of nematodes was 4077 per 100 g of the moss. Rhabditida, Tylenchida, Plectida and Dorylaimida composed had more species richness (12, 10, 8 and 7 species, respectively). Species of these four orders comprised 78.7%. Representatives of three order Plectida, Dorylaimida and Monhysterida were the most numerous within the considered communities (proportion in the communities were 40.75, 21.30 and 18.65%, respectively). The majority of the identified species were subrecedent (31 or 65.95% of species composition) and accidental species (37 or 78.72%). Three species: Plectus parietinus Bastian, 1865, Mesodorylaimus bastiani Bütschli, 1873 and Geomonhystera villosa Bütschli, 1873 composed the core of nematode communities from epiphytic mosses in the Left-bank Polesie. They were found in 70.21, 57.45 and 53.19% of the samples, proportion in the community of 15.21, 10.03 and 17.96%, respectively.
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Bibliography

Abebe, E., Andrássy, I., Truanspurger, W., 2006. Freshwater nematodes: ecology and taxonomy. Wallingford, Oxfordshire, UK; Cambridge, MA, USA: CABI Publ., 13–30.

Barbuto, M., Zullini, A., 2006. Moss inhabiting nematodes: influence of the moss substratum and geographical distribution in Europe. Nematology 8 (4), 575–582.

Bongers, T., 1990. The maturity index: an ecological measure of environmental disturbance based on nematode species composition. Oecologia 83, 14–19.

Gadea, E., 1988. Sobre la nematofauna muscicola de la Cordillera Real de los Andes de Bolivia. Publicaciones del Departamento de Zoologia, Universidade de Barcelona 14, 7–19.

Georgievska, M., 1990. Characteristics of nematodes community of the ground moss cover in an oak forest on Galicica. Fragmenta Balcanica 14, 151–154.

Glime, J.M., 2012. Invertebrates: Nematodes. Chapt. 4–3. In: Glime, J.M. (Ed.), Bryophyte Ecology 2. Bryological Interaction. 4-3-1 Ebook sponsored by Michigan Technological University and the International Association of Bryologists. www.bryoecol.mtu.edu.

Goodey, T., 1963. Soil and freshwater nematods. Revised by J.B. Goodey from 1951 Ed., 2nd Ed., Wiley, New York, 1–544.

Kiryanova, E.S., Krall, E.L., 1969. Parasitic Nematodes of Plants and Measures of their Control. Nauka, Leningrad, Vol. 1, 1–441 [In Russian].

Lazarova, S., Peneva, V., Peneva, L., 2000. Nematode assemblages from the moss Hypnum cupressiforme Hedw. growing on different substrates in a balkanic durmast oak forest (Quercus dalechampii Ten.) on Mount Vitosha, Bulgaria. Nematology 2, 263–272.

Matuszkiewicz, W., 2019, Przewodnik do oznaczania zbiorowisk roślinnych Polski. Wydawnictwo Naukowe PWN, Warszawa, 540 pp.

Mucina, L., Büultmann, H., Dierßen, K., Theurillat, J.-P., Raus, T., Čarni, A., Šumberová, K., Willner, W., Dengler, J., García, R.G., Chytrý, M., Hájek, M., Di Pietro, R., Iakushenko, D., Pallas, J., Daniёls, F.J.A., Bergmeier, E., Guerra, A.S., Ermakov, N., Valachovič, M., Schaminće, J.H.J., Lysenko, T., Didukh, Y.P., Pignatti, S., Rodwell, J.S., Capelo, J., Weber, H.E., Solomeshch, A., Dimopoulos, P., Aguiar, C., Hennekens, S.M., Tichý, L., 2016. Vegetation of Europe: hierarchical floristic classification system of vascular plant, bryophyte, lichen, and algal communities. Applied Vegetation Science 19 (S1), 3–264.

Nesterov, P.I., 1979. Plant parasitic and free-living nematodes of South-West of USSR. Edit. Stiinta. Chisinau, 1–312 [In Russian].

Sayre, R.M., Brunson, L.K., 1971. Microfauna of moss habitats. American Biology Teacher 33, 100–102, 105.

Shevchenko, V.L., Zhylina, T.M., 2016. Taxonomic structure of nematode communities of epiphytic mosses in green plantations of Chernihiv, Ukraine. Vestnik zoologii 50 (6), 477–482.

Solovyeva, G.I., 1986. Ekologia pochvennykh nematod. Nauka, Leningrad, 1–247 [In Russian].

Steiner, W.A., 1994a. The influence of air pollution on moss-dwelling animals: 1. Methodology and composition of flora and fauna. Revue suisse de Zoologie 101, 533–556.

Steiner, W.A., 1994b. The influence of air pollution on moss-dwelling animals: 2. Aquatic fauna with emphasis on Nematoda and Tardigrada. Revue suisse de Zoologie 101, 699–724.

Steiner, W.A., 1994c. The influence of air pollution on moss-dwelling animals: 4. Seasonal and long-term fluctuations of rotifer, nematode and tardigrade populations. Revue suisse de Zoologie 101, 1017–1031.

Steiner, W.A., 1995. The influence of air pollution on moss-dwelling animals: 5. Fumigation experiments with SO2 and exposure experiments. Revue suisse de Zoologie 102 (1), 13–40.

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Zullini, A., Peretti, E., 1986. Lead pollution and moss-inhabiting nematodes of an industrial area. Water, Air and Soil Pollution 27, 403–410.
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Authors and Affiliations

Valentyna Shevchenko
1
Tetiana Zhylina
1

  1. T.H. Shevchenko National University “Chernihiv Colehium”, 53, Hetman Polubotko Str., Chernihiv, 14013, Ukraine
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Abstract

The aim of the study was to verify the quality of ram semen, frozen in 1982-1983, from the historical collection of the Bank of Biological Material of the National Research Institute of Animal Production. A total of 18 ejaculates from 3 Świniarka type rams were analyzed to assess sperm motility (subjectively), total motility, progressive motility, sperm concentration (CASA), membrane integrity (SYBR-14/PI) and chromatin structure (SCSA). In order to determine sperm fertilizing ability 49 ewes were intracervically inseminated (200×106 sperm per AI) with frozen- thawed semen 12 and 24 hours after detection of estrus. Sperm motility parameters, membrane intact spermatozoa and DFI did not differ among the analyzed rams. Spermatozoa concentration was significantly higher for ram no. 2 than for rams no. 1 and 3. The lambing rates (27.3 to 36.0%) did not differ significantly for individual rams. The ram semen, which had been stored for around 40 years, showed satisfactory quality and fertilizing capacity, allowing for its use in artificial insemination.
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Authors and Affiliations

P. Gogol
1

  1. Department of Reproductive Biotechnology and Cryoconservation, National Research Institute of Animal Production, Krakowska 1, 32-083 Balice/Kraków, Poland
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Abstract

This work aims to further compensate for the weaknesses of feature sparsity and insufficient discriminative acoustic features in existing short-duration speaker recognition. To address this issue, we propose the Bark-scaled Gauss and the linear filter bank superposition cepstral coefficients (BGLCC), and the multidimensional central difference (MDCD) acoustic feature extracted method. The Bark-scaled Gauss filter bank focuses on low-frequency information, while linear filtering is uniformly distributed, therefore, the filter superposition can obtain more discriminative and richer acoustic features of short-duration audio signals. In addition, the multi-dimensional central difference method captures better dynamics features of speakers for improving the performance of short utterance speaker verification. Extensive experiments are conducted on short-duration text-independent speaker verification datasets generated from the VoxCeleb, SITW, and NIST SRE corpora, respectively, which contain speech samples of diverse lengths, and different scenarios. The results demonstrate that the proposed method outperforms the existing acoustic feature extraction approach by at least 10% in the test set. The ablation experiments further illustrate that our proposed approaches can achieve substantial improvement over prior methods.
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Authors and Affiliations

Yunfei Zi
1
Shengwu Xiong
1

  1. School of Computer and Artificial Intelligence, Wuhan University of Technology Wuhan, China
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Abstract

The aim of the work is to present one of the most important structures of the last decade — the European Central Bank in Frankfurt am Main, against the background of the role which a sustainable skyscraper can play in the urban composition of a modern city. A literature query and original in situ research show that from the beginning of the 20th century, skyscrapers have become a symbol of the success and importance of cities and metropolises. At the same time, most of the historic skylines of European cities were saved from ‘Manhattanization’. One of the exceptions is Frankfurt, the financial capital of the EU. This paper discusses the construction of the ECB building, both as another important landmark in the city’s urban composition and as an innovative, sustainable structure. The results show that the location of an important high-rise building with a prestigious function in the urban structure confirms the city’s status. At the same time, it was proved that the technological and formal solutions used in the complex, together with the reuse of the built structure (recycling of architecture), may contribute to the reduction of the carbon footprint and maintaining high environmental standards.
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Authors and Affiliations

Mateusz Gyurkovich
1
ORCID: ORCID
Zina Macri
2
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Architecture, Chair of Urbanism and City Structure Architecture
  2. Chair of Technical Sciences, Ion Mincu University of Architecture and Urbanism
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Abstract

Large-scale stone-banked lobes and terraces are distributed over an area of 1 km2 of gentle slope on Rink Plateau in the northern part of James Ross Island, Antarctic Peninsula region. Topographically, there are two main features: relatively high risers up to 5 m high and distinct frontal ridges. In order to understand the processes responsible for these lobes and terraces, the authors have monitored air and ground temperatures and movement of stones on the surface over the period 1995-2005. In February 2005, the subsurface structures were surveyed by ground penetrating radar and drilling. The ground penetrating radar profiles identified the bedrock surface. The surface morphology of the lobes corresponds closely with that of the bedrock. The relatively high risers of these lobes are presumed to be due to a cessation of frontal advance.

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Authors and Affiliations

Junko Mori
Kotaro Fukui
Toshio Sone
Jorge A. Strelin
Cesar A. Torielli
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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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  13. El-Ganiny, M. Y., Klialaf, A. A. M., Hussein, A. I. & Hamed, H. F. A. A preamble based channel estimation methods for FBMC waveform: A comparative study. Procedia Comput. Sci. 182, 63–70 (2020). https://doi.org/10.1016/j.procs.2021.02.009
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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 main objective of this paper is to produce an applications-oriented review covering infrared techniques and devices. At the beginning infrared systems fundamentals are presented with emphasis on thermal emission, scene radiation and contrast, cooling techniques, and optics. Special attention is focused on night vision and thermal imaging concepts. Next section concentrates shortly on selected infrared systems and is arranged in order to increase complexity; from image intensifier systems, thermal imaging systems, to space-based systems. In this section are also described active and passive smart weapon seekers. Finally, other important infrared techniques and devices are shortly described, among them being: non-contact thermometers, radiometers, LIDAR, and infrared gas sensors.

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Authors and Affiliations

A. Rogalski
K. Chrzanowski
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Abstract

A traditional frequency analysis is not appropriate for observation of properties of non-stationary signals. This stems from the fact that the time resolution is not defined in the Fourier spectrum. Thus, there is a need for methods implementing joint time-frequency analysis (t/f) algorithms. Practical aspects of some representative methods of time-frequency analysis, including Short Time Fourier Transform, Gabor Transform, Wigner-Ville Transform and Cone-Shaped Transform are described in this paper. Unfortunately, there is no correlation between the width of the time-frequency window and its frequency content in the t/f analysis. This property is not valid in the case of a wavelet transform. A wavelet is a wave-like oscillation, which forms its own “wavelet window”. Compression of the wavelet narrows the window, and vice versa. Individual wavelet functions are well localized in time and simultaneously in scale (the equivalent of frequency). The wavelet analysis owes its effectiveness to the pyramid algorithm described by Mallat, which enables fast decomposition of a signal into wavelet components.

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Authors and Affiliations

Andrzej Majkowski
Marcin Kołodziej
Remigiusz J. Rak
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Abstract

Visible light communication based on a filter bank multicarrier holds enormous promise for optical wireless communication systems, due to its high-speed and unlicensed spectrum. Moreover, visible light communication techniques greatly impact communication links for small satellites like cube satellites, and pico/nano satellites, in addition to inter-satellite communications between different satellite types in different orbits. However, the transmitted visible signal via the filter bank multicarrier has a high amount of peak-to-average power ratio, which results in severe distortion for a light emitting diode output. In this work, a scheme for enhancing the peak-to-average power ratio reduction amount is proposed. First, an algorithm based on generating two candidates signals with different peak-to-average power ratio is suggested. The signal with the lowest ratio is selected and transmitted. Second, an alternate direct current-biased approach, which is referred to as the addition reversed method, is put forth to transform transmitted signal bipolar values into actual unipolar ones. The performance is assessed through a cumulative distribution function of peak-to-average power ratio, bit error rate, power spectral density, and computational complexity. The simulation results show that, compared to other schemes in literature, the proposed scheme attains a great peak-to-average power ratio reduction and improves the bit the error rate performance with minimum complexity overhead. The proposed approach achieved about 5 dB reduction amount compared to companding technique, 5.5 dB compared to discrete cosine transform precoding, and 8 dB compared to conventional direct current bias of an optical filter bank multicarrier. Thus, the proposed scheme reduces the complexity overhead by 15.7% and 55.55% over discrete cosine transform and companding techniques, respectively.
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Authors and Affiliations

Radwa A. Roshdy
1
ORCID: ORCID
Aziza I. Hussein
2
ORCID: ORCID
Mohamed M. Mabrook
3 4
ORCID: ORCID
Mohammed A. Salem
ORCID: ORCID

  1. Department of Electrical Engineering, Higher Technological Institute, 10th of Ramadan City, Egypt
  2. Electrical & Computer Eng. Dept., Effat University, Jeddah, Saudi Arabia
  3. Space Communication Dept., Faculty of Navigation Science & Space Technology, Beni-Suef University, Beni-Suef, Egypt
  4. Department of Communication and Computer Engineering, Faculty of Engineering, Nahda University in Beni-Suef, Egypt
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Abstract

The design of a low complexity multiplier-less narrow transition band filter bank for the channelizer of multistandard software-defined radio (SDR) is investigated in this paper. To accomplish this, the modal filter and complementary filter in the upper and lower branches of the conventional Frequency Response Masking (FRM) architecture are replaced with two power-complementary and linear phase filter banks. Secondly, a new masking strategy is proposed to fully exploit the potential of the numerous spectra replicas produced by the interpolation of the modal filter, which was previously ignored in the existing FRM design. In this scheme, the two masking filters are appropriately modulated and alternately masked over the spectra replicas from 0 to 2π, to generate even and odd channels. This Alternate Masking Scheme (AMS) increases the potency of the Modified FRM (ModFRM) architecture for the design of computationally efficient narrow transition band uniform filter bank (termed as ModFRM-FB). Finally, by combining the adjoining ModFRM-FB channels, Non-Uniform ModFRMFB (NUModFRM-FB) for extracting different communication standards in the SDR channelizer is created. To reduce the total power consumption of the architecture, the coefficients of the proposed system are made multiplier-less using Matching Pursuits Generalized Bit-Planes (MPGBP) algorithm. In this method, filter coefficients are successively approximated using a dictionary of vectors to give a sum-of-power-of-two (SOPOT) representation. In comparison to all other general optimization techniques, such as genetic algorithms, the suggested design method stands out for its ease of implementation, requiring no sophisticated optimization or exhaustive search schemes. Another notable feature of the suggested approach is that, in comparison to existing methods, the design time for approximation has been greatly reduced. To further bring down the complexity, adders are reused in recurrent SOPOT terms using the Common Subexpression Elimination (CSE) technique without compromising the filter performance.
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Authors and Affiliations

A.K. Parvathi
1
V. Sakthivel
1

  1. National Institute of Technology, Calicut, India
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Abstract

Parallel realizations of discrete transforms (DTs) computation algorithms (DTCAs) performed on graphics processing units (GPUs) play a significant role in many modern data processing methods utilized in numerous areas of human activity. In this paper the authors propose a novel execution time prediction model, which allows for accurate and rapid estimation of execution times of various kinds of structurally different DTCAs performed on GPUs of distinct architectures, without the necessity of conducting the actual experiments on physical hardware. The model can serve as a guide for the system analyst in making the optimal choice of the GPU hardware solution for a given computational task involving particular DT calculation, or can help in choosing the best appropriate parallel implementation of the selected DT, given the limitations imposed by available hardware. Restricting the model to exhaustively adhere only to the key common features of DTCAs enables the authors to significantly simplify its structure, leading consequently to its design as a hybrid, analytically–simulational method, exploiting jointly the main advantages of both of the mentioned techniques, namely: time-effectiveness and high prediction accuracy, while, at the same time, causing mutual elimination of the major weaknesses of both of the specified approaches within the proposed solution. The model is validated experimentally on two structurally different parallel methods of discrete wavelet transform (DWT) computation, i.e. the direct convolutionbased and lattice structure-based schemes, by comparing its prediction results with the actual measurements taken for 6 different graphics cards, representing a fairly broad spectrum of GPUs compute architectures. Experimental results reveal the overall average execution time and prediction accuracy of the model to be at a level of 97.2%, with global maximum prediction error of 14.5%, recorded throughout all the conducted experiments, maintaining at the same time high average evaluation speed of 3.5 ms for single simulation duration. The results facilitate inferring the model generality and possibility of extrapolation to other DTCAs and different GPU architectures, which along with the proposed model straightforwardness, time-effectiveness and ease of practical application, makes it, in the authors’ opinion, a very interesting alternative to the related existing solutions.
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Authors and Affiliations

Dariusz Puchala
1
ORCID: ORCID
Kamil Stokfiszewski
1
ORCID: ORCID
Kamil Wieloch
1

  1. Institute of Information Technology, Łódź University of Technology, ul. Wólczańska 215, 90-924 Łódź, Poland

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