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Number of results: 36
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Abstract

The article is an attempt to present and discuss – based on the struggle against Barbary pirates and corsairs waged in the Mediterranean Sea – dynamic and complex political and economic processes as well as diplomatic efforts that contributed to the French conquest of Algiers in 1830. The first three decades of the 19th century were among the most turbulent periods in the history of the French nation. Defeated and humiliated by the enemy coalition in 1815, France did not give up on her “imperial dream”, this time trying to make it come true in a non-distant Maghreb. The way to achieve this goal was, however, quite bumpy. At that time, the western part of the Mediterranean Sea was an arena of competition, mainly between the United States and Great Britain. After all, this turned out to be very favourable to France. Wishing to introduce an extra element into the game, eliminate rivals for overseas supremacy, as well as win Russia – that was gradually strengthening her influence in the eastern part of the Mediterranean Sea – as an ally, at the end of the 1820’s Great Britain became an advocate of her neighbour across the English Channel. Gradually regaining her economic potential and international importance, France reached for Algiers by entering the armed conflict. However, the French stronghold in Maghreb would soon pose a major challenge to the British colonialism in Africa. Expressing their major concern over the security of so-called “imperial route” leading via the Mediterranean sea, British politicians and statesmen adopted a new political stance toward the declining Ottoman Empire. Owing to their “independence and integrity” doctrine (formulated in 1830’s), the rich Ottoman heritage managed to “survive” by the outbreak of World War II.
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Authors and Affiliations

Zygmunt Stefan Zalewski
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Abstract

The article discusses the matter of portraying Suleiman I the Magnificent in 16th century Croatian and Slovakian literature. The source material comprises three texts: Ferenc Črnko’s Croatian chronicle titled Podsjedanje i osvojenje Sigeta [The Siege and Capture of Siget], the Croatian epic tale Vazetje Sigeta grada [The Caputure of Siget Town] by Brne Karnarutić and the Slovakian anonymous historical song Píseň o Sigetském zámku [A Song about Siget Castle]. By looking at these texts the author hereof contemplates what image of the Turkish ruler has been recorded in Slavic literatures.

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Authors and Affiliations

Monika Sagało
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Abstract

Consciousness was the guiding thread of Edmund Husserl's phenomenological investigations. He understood it as a critique of experience and the metaphysics and science based on it. Phenomenology is a critique of cognition, a method of investigation and questioning. In his later writings Husserl defined consciousness as a “system of intentional functions,” a “system of intentional operations.” Its correlate is a coherent and regularized world. One of the most important aspects of the system of intentional functions are habitualities—patterns, mental representations which arise in the process of “typification” and henceforth guide our ordinary thinking and acting. Thanks to them, the type of object, its features and properties are predetermined and, in principle, the ways of knowing it are determined. My task is to characterize the broad context of habituality formation, that is, the stream of consciousness and the possibilities of feeling and movement of the bodily subject. I will discuss in turn the temporal structure of experience and its dependence on the movement and action of the bodily subject, and then characterize the form of general intimacy with the world. It is in this context of “indeterminate reality” that the constitution and evocation of the deposited sense, the anticipation of the type of object and its qualities play out. In conclusion, I will make some remarks about habituality as a source of empirical concepts.
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Authors and Affiliations

Marek Maciejczak
1

  1. Politechnika Warszawska, Wydział Administracji i Nauk Społecznych, plac Politechniki1, 00-614 Warszawa
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Abstract

In the paper I try to reconstruct the main theoretical assumptions underlying Paul Veyne’s vision of the ancient world that are to be found in his book L’empire gréco-romain. First of all, recalling the opposition between two ways of making the past intelligible: “explication” versus “explicitation”, I show how the French historian uses that second type of historical analyse to reveal some ancient phenomena (i.e. “democracy”, “imperialism”, “soul”, “faith”) in their original and singular forms. Then, I pass to the question of causality and genesis in history. It seems that in Veyne’s book we can distinguish three different “models” of becoming: 1) “time of a project”, 2) “epigenesis” and 3) “discourse effectiveness”. All these fi ndings lead me to the conclusion that Veyne’s writing of history is essentially “essayistic”.
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Authors and Affiliations

Tomasz Falkowski
ORCID: ORCID
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Abstract

This article analyzes the heuristic value of the possible application of postcolonial approaches to nineteenth-century Habsburg Galicia. It critically reviews some contemporary usages of “postcolonial” in Ukrainian historiography, and political and literary criticism. The article finds original postcolonial historical approaches to be of great heuristic value, especially for practitioners of social history. Using “postcolonial” tools, historical research may yield new insights into the history of nineteenth-century Galicia

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Authors and Affiliations

Andriy Zayarnyuk
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Abstract

The article is a review of the book edited by Krzysztof Brzechczyn, The Paths of Transformation. Theoretical Approach and Empirical Descriptions, Poznań 2003.
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Authors and Affiliations

Mariusz Weiss
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Abstract

The present study modelled the effects of operational parameters on the performance of the Falcon concentrator. For this purpose, the Falcon L40 concentrator was tested in narrow particle-size fractions (−600 + 425 μm, −425 + 300 μm, −300 + 212 μm, −212 + 150 μm, −150 + 106 μm, and −106 + 75 μm) at different washing water pressures and artificial gravity forces generated by a spinning bowl. The test samples were prepared artificially, comprising 2% magnetite (Fe3O4) and 98% calcite (CaCO3) by weight. The recovery and grade values of the 60 experimental conditions were investigated and compared for different operational parameters, including particle-size distributions, water pressures, and artificial gravity forces. Two empirical models were developed using non-linear regression analysis to indicate the effects of the operating parameter of the Falcon concentrator on its recovery and grade values. The operational parameters were found to impact the separation performance considerably. Therefore, the Falcon concentrator should operate under optimum conditions, which can be easily predicted using these models, to achieve improved recovery and grade values.
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Authors and Affiliations

Namik Atakan Aydogan
1
ORCID: ORCID
Murat Kademli
1
ORCID: ORCID

  1. Hacettepe University, Mining Engineering Department, Turkey
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Abstract

Rainfall is one of the main components of the hydrologic cycle; thus, the availability of accurate rainfall data is fundamental for designing and operating water resources systems and infrastructure. This study aims to develop an empirical model of rainfall intensity ( It,p) as a function of its probability ( p) and duration ( t). In 1999–2020, data on the hourly duration of rainfall were collected from automatic rainfall recorder (ARR) gauges. The empirical model has been developed using a statistical approach based on duration ( t) and probability ( p), and subsequently they have been validated with those obtained from ARR data. The resulting model demonstrates good performance compared with other empirical formulas (Sherman and Ishiguro) as indicated by the percent bias ( PBIAS) values (2.35–3.17), ratio of the RMSE (root mean square error) between simulated and observed values to the standard deviation of the observations ( RSR, 0.028–0.031), Nash–Sutcliffe efficiency ( NSE, 0.905–0.996), and index of agreement (d, 0.96–0.98) which classified in the rating of “very good” in model performance. The reliability of the estimated intensity based on the empirical model shows a tendency to decrease as duration ( t) increases, and a good accuracy mainly for the rainfall intensity for shorter periods (1-, 2-, and 3-hours), whereas low accuracy for long rainfall periods. The study found that the empirical model exhibits a reliable estimate for rainfall intensity with small recurrence intervals ( Tr) 2-, 5-, 10-, and a 20-year interval and for a shorter duration ( t). Validation results confirm that the rainfall intensity model shows good performance; thus, it could be used as a reliable instrument to estimate rainfall intensity in the study area.
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Authors and Affiliations

Donny Harisuseno
1
ORCID: ORCID
Linda Prasetyorini
1
ORCID: ORCID
Jadfan S. Fidari
1
ORCID: ORCID
Dian Chandrasasi
1
ORCID: ORCID

  1. University of Brawijaya, Faculty of Engineering, Water Resources Engineering Department, MT. Haryono Street No. 167, 65145, Malang, Indonesia
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Abstract

This study analyses and presents a technical comparison of seepage estimation from 11 empirical equations with measured seepage losses by the inflow-outflow method from two lined and unlined secondary irrigation canals sub-divided into different reach lengths. A significant margin of error was observed between empirical and inflow- outflow methods, hence modifications in empirical equations were performed. Results reveal that the average seepage losses observed in unlined and lined canals by inflow-outflow method were 9.15 and 3.89%, respectively. Moreover, only the Chinese equation estimated seepage losses for an unlined canal as similar to observed losses (0.11 m 3∙s –1) whereas the Indian equation estimated similar results for a lined canal to those observed in the field (0.09 m 3∙s –1). However, the rest of empirical equations were modified in accordance with error percentage with regard to the observed losses. The empirical equations were then observed to estimate reliable results of seepage.
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Authors and Affiliations

Naeem S.B. Syed
1
ORCID: ORCID
Zhao Shuqi
1
ORCID: ORCID

  1. Beijing University of Technology, Faculty of Architecture, Civil and Transportation Engineering, 100124 Beijing, China
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Abstract

Ethicists have thus far not paid much attention to uncertainty, very often concentrating on highly idealized hypothetical situations where both empirical (e.g. the state of the world, the spectrum of possible decisions and their consequences, the causal connections between events) and normative (the content of norms, value scales) matters were clearly defined and well-known to the decision-maker. In this article, which stems from a project on different types of decisions under uncertainty related to the rapid progress in biomedical research, I analyze some situations of normative uncertainty, cases when an agent must make a decision, but does not know which choice is correct, for example, because he/she has contrary intuitions about the permissibility of available decisions. The view termed comparativism claims that in such cases the appropriate decision depends not only on the credences that one assigns to different norms, but also on how much possible decisions are worth taking in the light of these norms. I analyze a few cases of normative uncertainty, and a specific counter-argument against the current versions of comparativism, showing that under normative uncertainty this view imposes risk neutrality, although it permits us to have different risk attitudes under empirical uncertainty. I also argue that a precautionary approach to situations of normative uncertainty is overly simplistic.

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Authors and Affiliations

Tomasz Żuradzki
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Abstract

The reviewed book was written basing on Piotr Szlanta’s habilitation thesis defended in 2015 at the University of Warsaw. It deals mainly with “the Polish question”, by describing the relations between Emperor Wilhelm II and his Polish subjects. The title deals with stereotypes of the Emperor and his Polish subjects, and its evolution during subsequent decades. Piotr Szlanta managed to grasp the ambiguous relation between these two sides. On the one hand, the Emperor sought for acceptance and recognition from the side of “his Poles”, on the other hand, he underlined on almost every occasion the historical role of Germans in civilising east territories and its inhabitants. The last attempt of gaining support of Poles towards his politics and himself was an attempt of creating “The Kingdom of Poland” in autumn 1916. Piotr Szlanta’s book, basing on a broad research in various archives managed to highlight this complicated chapter of Polish-German relations.

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Authors and Affiliations

Jens Boysen
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Abstract

We propose an empirical equation to predict the martensite start temperatures of highly alloyed steels containing more than 3 wt.% of Ni or Cr or 2 wt.% of Mo, W, or Co. The martensite start temperature calculated by the proposed equation was in good agreement with experimental data owing to not only the derivation from experimental data of alloy steels with a wide range of chemical compositions but also the interaction term between carbon and carbide-forming alloying elements.

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Authors and Affiliations

Seok-Jae Lee
ORCID: ORCID
Minsu Jung
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Abstract

In the chaotic situation following the British invasion of southern Palestine at the end of 1917, military officials faced several countervailing pressures. In addition to ongoing military priorities (including international norms pertaining to military occupations, such as the law of the ‘status quo’), pressing humanitarian concerns, and even the personal religious sentiments of individual officers, the British occupation administration was forced to take into account international pressures and interventions resulting from the overlapping and conflicting promises made during the war (inter alia, Sykes‑Picot agreement, Husayn‑McMahon correspondence, Balfour Declaration, and President Wilson’s 14 Points). This paper focuses on the land policy‑making process as a case study with which to weigh the various factors pressing upon the military occupation as it evolved during its first three years. Land ownership was a huge concern: a properly functioning land registry was seen as key to the improvement of economic and social conditions in the largely agricultural economy, and British interventions were followed closely by all interested parties. The land has also been at the centre of the ensuing century‑long conflict between Arabs and Jews. Thus, a close examination of land policies (and especially the 1920 land ordinance) offers an extremely important window on both the rule of law in the aftermath of the war and our understanding of the current, unending conflict in the land.
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Authors and Affiliations

Martin Bunton
1
ORCID: ORCID

  1. University of Victoria
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Abstract

To study the difference in seismic vulnerability of multiple typical structures in multiple intensity zones, the seismic damage of 7099 buildings of Dujiangyan masonry structure (MS), reinforced concrete structure (RC) and bottom frame seismic wall masonry (BFM) in the 2008 Wenchuan earthquake in China is summarized and analysed. First, a statistical analysis of the data is carried out, the empirical seismic vulnerability matrix and model curves are established by considering the number of storeys, the age and the fortification factors.The vulnerability curves of the cumulative exceeding probability of the empirical seismic damage and the grade of the seismic damage in multiple intensity zones are shown. The mean damage index vulnerability matrix model is proposed and verified using the empirical seismic damage matrix of typical structures.

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Authors and Affiliations

S.Q. Li
T.L. Yu
Y.S. Chen
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Abstract

To reduce the random error of microelectromechanical system (MEMS) gyroscope, a hybrid method combining improved empirical mode decomposition (EMD) and least squares algorithm (LS) is proposed. Firstly, based on the multiple screening mechanism, intrinsic mode functions (IMFs) from the first decomposition are divided into noise IMFs, strong noise mixed IMFs, weak noise mixed IMFs and signal IMFs. Secondly, according to their characteristics, they are processed again. IMFs from the second decomposition are divided into noise IMFs and signal IMFs. Finally, useful signal is gathered to obtain the final denoising signal. Compared with some other denoising methods proposed in recent years, the experimental results show that the proposed method has obvious advantages in suppressing random error, greatly improving the signal quality and improving the accuracy of inertial navigation.
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Authors and Affiliations

Hailong Rong
1
Tianlei Jin
1
Hao Wang
1
Xiaohui Wu
1
Ling Zou
1

  1. Changzhou University, Changzhou 213164, China
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Abstract

The article is devoted to the ancient tradition in the European art and the impact of antiquity on our European identity. The issue of reception of ancient models in art, in particular in the architecture of the Middle Ages, thus the epoch that was chronologically closest to the heritage of the Imperium Romanum, has accompanied the author since the very beginning of her academic career. Such personal approach to the issue and strong belief about the significance of the accomplishments of ancient culture for the development of European artistic thought resulted in the fact that the author decided to come back to it. In spite of the passage of time, it is still a valid subject matter, consistently pursued by Polish and foreign researchers.
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Authors and Affiliations

Klaudia Stala
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Abstract

Eugene Schuyler was the first American to travel to Central Asia. Recognized as a scholar diplomat, he had written extensively on Russia and served as the US consul to Reval and the secretary of the American legation in St. Petersburg. During his diplomatic service in Russia, Schuyler was granted absence of leave to visit Central Asia and witnessed the Russian conquest of the region. He was also accompanied by the Russian army to visit the Ili region in Xinjiang amid the Dungan Revolt (1862–1877). Schuyler’s unusual experience was detailed in his travelogue Turkistan, Notes of a Journey in Russian Turkistan, Khokand, Bukhara, and Kuldja. This paper aims to analyze his travelogue to track down the earliest American contact with Central Asia. It argues that the US, even though aware of Russian military activity in the region from Schuyler’s report, tacitly acknowledged Russia’s hegemony in Asia. This could be attributable to Schuyler’s partiality to Russia’s cause, the generally congenial atmosphere in the US-Russia relations in the 1870s, and the absence of perceived US interests in Central Asia. The US foreign policy decision of the 1870s had far-reaching economic consequences and lasting political implications into the 19 th century and beyond.
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Authors and Affiliations

Yi Zhang
1
ORCID: ORCID

  1. John F. Kennedy Institute for North American Studies,Freie Universität Berlin, Germany
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Abstract

The article presents the two known Poland-related statements by the Hungarian Orientalist Arminius Vámbéry (1832–1913), who explained his opinion on the possible independence of a Polish state twice – in 1898 and 1906. In 1898, he was interviewed by the Budapest correspondent of the Kraków-based Polish newspaper Nowa Reforma. In 1906, he answered an international survey by the cultural journal Krytyka, based in Kraków as well. Vámbéry’s answer to the question of whether Poland should gain independence once again was positive. Still, he justified the necessity of Polish independence not with the interests of the Polish people but with Europe’s wish to be protected from the Russian Empire: to Vámbéry’s mind, an independent Poland should serve as Europe’s bulwark against the Russian enemy. Vámbéry’s fear of the Russian Empire might be in line with his previous views on the Great Game, the rivalry between the Russian Empire and Great Britain on influence in Central Asia, and the European public opinion at the end of the 19th century.
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Authors and Affiliations

Sebastian Cwiklinski
1
ORCID: ORCID

  1. Freie Universität Berlin, Deutschland
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Abstract

The film art of the Russian Empire, in the light of the current state of research, may not be completely terra incognita, and yet a number of issues on this topic still need to be elaborated and saved from oblivion. The subject of the present research are the lost or only partially preserved horror movies filmed in the country of the last tsar of Russia – Nicholas II. The author recalls the circumstances of the creation of specific films, as well as the critical reception of such productions as Vasily Goncharov’s Viy (1909), At Midnight in the Graveyard (1909/1910) by the same director, The Vampire Woman (1915) by Viatcheslav (Victor) Tourjansky or two films by Ladislas Starevich: The Portrait (1915) and another screen adaptation of Viy (1916?).
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Authors and Affiliations

Marcin Cybulski
1
ORCID: ORCID

  1. Lublin, Katolicki Uniwersytet Lubelski Jana Pawła II
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Abstract

The European reference frame ETRF2000 was introduced on the territory of Poland on 1 July 2013, named PL-ETRF2000, as a result of the appropriate measurement campaign 2008-2011. The new PL-ETRF2000 reference frame has replaced the previously used PL-ETRF89 frame, which had more than 10 years of history in Poland until 2013, implemented in almost all geodetic and cartographic “products”, in geodetic networks, economic map systems and databases. The relationship of the new reference frame with the previously used PL-ETRF89 frame has become an important practical issue. Currently, all position services of the ASG-EUPOS (Active Geodetic Network – EUPOS) system use only the PL-ETRF2000 reference frame, which also results from the relevant legal and technical regulations. The relationships between the frames was considered in two aspects: “theoretical”, expressed by conformal (Helmert, 7-parameter) transformation, and “empirical”, based on an interpolation grid that allows to take into account local distortions of the PL-ETRF89 frame. The estimation of the parameters of the conformal transformation model was based on 330 points of the POLREF network, while to create an interpolation grid approximately 6500 points of the old triangulation network were additionally used, after new adjustment in PL-ETRF200 reference frame. Basic algorithms for the transformation between two frames and mapping systems are implemented in the new version of the TRANSPOL program, which is available on the web ( www.gugik.gov.pl).
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Bibliography

Balcerzak, J. (1994). Odwzorowanie Gaussa-Krügera w szerokiej 12° strefie dla obszaru Polski. IX Szkoła Kartograficzna. Komorowo, 10–14.10.1994.

Bosy, J. (2011). Weryfikacja wyników integracji podstawowej osnowy geodezyjnej na obszarze kraju ze stacjami referencyjnymi systemu ASG-EUPOS. Wrocław, 30.11.2011. Raport dla GUGiK Warszawa.

Deakin, R.E. (1998). 3D Coordinate transformations. Survey. Land Inf. Systems. 58, 4, pp. 223–234.

Deutsch, R. (1965). Estimation Theory. Englewood Cliffs: Prentice-Hall, Inc.

Jaworski, L. (2011). Zintegrowanie podstawowej osnowy geodezyjnej na obszarze Polski ze stacjami referencyjnymi systemu ASG-EUPOS ETAP IV. Opracowanie i wyrównanie obserwacji GNSS. Raport CBK dla GUGiK, lipiec 2011, Warszawa (Pomiary wykonane przez konsorcjum firm geodezyjnych).

Hausbrandt, S. (1971). Rachunek wyrównawczy i obliczenia geodezyjne. Tom I i II. Warszawa: PPWK. Transformation between the PL-ETRF89 and PL-ETRF2000 frames 19

Kadaj, R. (2001). Formuły odwzorowawcze i parametry układów współrzędnych (Mapping formulas and parameters of coordinate systems). Wytyczne Techniczne G-1.10. GUGiK 2001, ISBN-83-239- 1473-7.

Kadaj, R. and Świętoń, T. (2012). TRANSPOL wersja 2.06 – program do transformacji współrzędnych i wysokości w państwowym systemie odniesień przestrzennych – metody, algorytmy i opis programu (TRANSPOL version 2.06 – a program for the transformation of coordinates and heights in the state system of spatial references – methods, algorithms and description of the program). Internet publication of GUGiK – Head of the Office of Geodesy and Cartography, www.gugik.gov.pl.

Kadaj R. (2013). Skutki metryczne zmiany układów odniesienia: PL-ETRF89 na PL-ETRF2000 oraz PLKRON86- NH na PL-EVRF2007-NH w obszarze Polski (Metric effects of change of reference systems: PL-ETRF89 on PL-ETRF2000 and PL-KRON86-NH on PL-EVRF2007-NH in the area of Poland). In conf. Sekcji Geod. Sat. Komitetu Badań Kosmicznych i Satelitarnych PAN “Satelitarne metody wyznaczania pozycji we współczesnej geodezji i nawigacji”. AGH, Cracow, 24–27.09.2013.

Kozakiewicz, W. (1998). Wyrównanie pierwsza klasa. Geodeta, no. 2(33).

Liwosz, T., Rogowski, J., Kruczyk, M. et al. (2011). Wyrównanie kontrolne obserwacji satelitarnych GNSS wykonanych na punktach ASG-EUPOS, EUREF-POL, EUVN, POLREF i osnowy I klasy wraz z ocena wyników. Katedra Geodezji i Astronomii Geodezyjnej Wydział Geodezji i Kartografii Politechnika Warszawska. Warszawa, 15.12.2011. Raport dla GUGiK Warszawa.

Watson, G.A. (2006). Computing Helmert transformation. J. Comput. Appl. Math., 197, 387–394.

Zawadzki, J. (2011). Metody geostatyczne (Geostatic methods).Warszawa: Oficyna Wydawnicza Politechniki Warszawskiej.
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Authors and Affiliations

Roman Kadaj
1
ORCID: ORCID

  1. Rzeszów University of Technology, Rzeszów, Poland
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Abstract

The most challenging in speech enhancement technique is tracking non-stationary noises for long speech segments and low Signal-to-Noise Ratio (SNR). Different speech enhancement techniques have been proposed but, those techniques were inaccurate in tracking highly non-stationary noises. As a result, Empirical Mode Decomposition and Hurst-based (EMDH) approach is proposed to enhance the signals corrupted by non-stationary acoustic noises. Hurst exponent statistics was adopted for identifying and selecting the set of Intrinsic Mode Functions (IMF) that are most affected by the noise components. Moreover, the speech signal was reconstructed by considering the least corrupted IMF. Though it increases SNR, the time and resource consumption were high. Also, it requires a significant improvement under nonstationary noise scenario. Hence, in this article, EMDH approach is enhanced by using Sliding Window (SW) technique. In this SWEMDH approach, the computation of EMD is performed based on the small and sliding window along with the time axis. The sliding window depends on the signal frequency band. The possible discontinuities in IMF between windows are prevented by the total number of modes and the number of sifting iterations that should be set a priori. For each module, the number of sifting iterations is determined by decomposition of many signal windows by standard algorithm and calculating the average number of sifting steps for each module. Based on this approach, the time complexity is reduced significantly with suitable quality of decomposition. Finally, the experimental results show the considerable improvements in speech enhancement under non-stationary noise environments.

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Authors and Affiliations

Selvaraj Poovarasan
Eswaran Chandra
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Abstract

The empirical mode decomposition (EMD) algorithm is widely used as an adaptive time-frequency analysis method to decompose nonlinear and non-stationary signals into sets of intrinsic mode functions (IMFs). In the traditional EMD, the lower and upper envelopes should interpolate the minimum and maximum points of the signal, respectively. In this paper, an improved EMD method is proposed based on the new interpolation points, which are special inflection points (SIP n) of the signal. These points are identified in the signal and its first ( n − 1) derivatives and are considered as auxiliary interpolation points in addition to the extrema. Therefore, the upper and lower envelopes should not only pass through the extrema but also these SIP n sets of points. By adding each set of SIP i (i = 1, 2, ..., n) to the interpolation points, the frequency resolution of EMD is improved to a certain extent. The effectiveness of the proposed SIP n-EMD is validated by the decomposition of synthetic and experimental bearing vibration signals.
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Authors and Affiliations

Mohsen Kafil
1 2
Kaveh Darabi
2
Saeed Ziaei-Rad
3

  1. Mechanical Engineering Group, Pardis College, Isfahan University of Technology, Isfahan, Iran
  2. Mobarakeh Steel Company, Isfahan, Iran
  3. Department of Mechanical Engineering, Isfahan University of Technology, Isfahan, Iran
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Abstract

This paper aims to address the problems of inaccurate location and large computation in hybrid transmission line traveling wave detection methods. In this paper, a new fault location method based on empirical Fourier decomposition (EFD) and the Teager energy operator (TEO) is proposed. Firstly, the combination of EFD and the TEO is used to detect the time difference between the arrival of the initial traveling wave of the fault at the two measurement ends of the hybrid line. Then, when the fault occurs at the midpoint of each line segment and at the connection point of the hybrid line, the time difference between the arrival of the fault traveling wave at the two measurement ends of the line is calculated according to the line parameters. By comparing the obtained time differences, it is determined whether the fault occurs in the first or second half of the line. Finally, the fault distance is calculated using the double-ended traveling wave method according to the fault section. The model was built on PSCAD and the proposed algorithm was simulated on MATLAB platform. The results demonstrate that the proposed method achieves an average fault location accuracy of 98.88% by adjusting transition resistances and fault distances and comparing with other location methods. After validation, the proposed method for locating faults has a high level of accuracy in location, computational efficiency, and reliability. It can accurately identify fault segments and locations in hybrid transmission line systems.
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Authors and Affiliations

Caixia Tao
1
Baosheng Xing
1
Taiguo Li
1

  1. School of Automation and Electrical Engineering, Lanzhou Jiaotong University, Gansu Province, China
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Abstract

Since wind power generation has strong randomness and is difficult to predict, a class of combined prediction methods based on empiricalwavelet transform(EWT) and soft margin multiple kernel learning (SMMKL) is proposed in this paper. As a new approach to build adaptive wavelets, the main idea is to extract the different modes of signals by designing an appropriate wavelet filter bank. The SMMKL method effectively avoids the disadvantage of the hard margin MKL method of selecting only a few base kernels and discarding other useful basis kernels when solving for the objective function. Firstly, the EWT method is used to decompose the time series data. Secondly, different SMMKL forecasting models are constructed for the sub-sequences formed by each mode component signal. The training processes of the forecasting model are respectively implemented by two different methods, i.e., the hinge loss soft margin MKL and the square hinge loss soft margin MKL. Simultaneously, the ultimate forecasting results can be obtained by the superposition of the corresponding forecasting model. In order to verify the effectiveness of the proposed method, it was applied to an actual wind speed data set from National Renewable Energy Laboratory (NREL) for short-term wind power single-step or multi-step time series indirectly forecasting. Compared with a radial basic function (RBF) kernelbased support vector machine (SVM), using SimpleMKL under the same condition, the experimental results show that the proposed EWT-SMMKL methods based on two different algorithms have higher forecasting accuracy, and the combined models show effectiveness.
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Bibliography

[1] Wang Q., Martinez-Anido C.B., Wu H.Y., Florita A.R., Hodge B.M., Quantifying the economic and grid reliability impacts of improved wind power prediction, IEEE Transactions on Sustainable Energy, vol. 7, no. 4, pp. 1525–1537 (2016), DOI: 10.1109/TSTE.2016.2560628.
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Authors and Affiliations

Jun Li
1
Liancai Ma
1

  1. Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China

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