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Number of results: 13
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Abstract

Is this article simulation of statistical measurements is performed on the basis of which the analysis of the standard deviation of the obtained results is carried out. It is shown that the standard deviation is minimum and independent from measurement duration while an object is in the state of equilibrium. For objects in a stationary non-equilibrium state the standard deviation depends on the duration measurements and the parameters of the state. The influence of these factors on the standard deviation is assessed with equation which includes the relaxation time. The value of the relaxation time is determined by approximating the energy spectrum of the studied signals. The analysis of energy spectra showed that the spectrum of white noise is inherent in objects in equilibrium; the flicker component of the spectrum occurs when the state of the object deviates from equilibrium.
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Authors and Affiliations

Krzysztof Przystupa
1
Zenoviy Kolodiy
2
Svyatoslav Yatsyshyn
2
Jacek Majewski
3
Yuriy Khoma
2
Iryna Petrovska
2
Serhiy Lasarenko
2
Taras Hut
2

  1. Department Automation, Lublin University of Technology, ul. Nadbystrzycka 36, 20-618 Lublin, Poland
  2. Lviv Polytechnic National University, Institute of Computer Technologies, Automatics and Metrology, S. Bandera Str. 28a, 79013, Lviv, Ukraine
  3. Department of Automation and Metrology, Lublin University of Technology, ul. Nadbystrzycka 38D, 20-618 Lublin, Poland
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Abstract

In this paper, the deviation from eutectic composition in boundary layer for eutectic growth is studied by phase-field method. According to a series of artificial phase diagram, the lamellar eutectic growth of these alloy is simulated during directional solidification. At steady state, average growth velocity of eutectic lamella is equal to the pulling velocity. With the increasing of the liquidus slope of β phase, the average composition in boundary layer would deviate from eutectic composition and the deviation increases. The constitutional undercooling difference between both solid phases caused by the deviation increases with the increasing of the deviation. The β phase would develop a depression under the influence of the deviation.

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Authors and Affiliations

Zhixin Tu
Jianxin Zhou
Yajun Yin
Xiaoyuan Ji
Xu Shen
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Abstract

The article studies the problems of forming intentional deformations of a narrative category of event in the prose of a famous Russian absurdist of the 1920s‑30s, a member of the avant‑garde collective Oberiu – Daniil Kharms. The study defines the main regularities of generating “normal” textual events as well as the mechanisms for their deformations and destructions within a narrative “story” and its “discourse”. The most important reasons for the “ludic” absurdity of events within D. Kharms’ short stories are the unintelligibility of the described objects, the ontological absurdity of the objects of events, the absurdity of the heroes’ behaviour and thinking, the sequence (multiplication) of events, the violation of structural order and the integrity of the described objects and their constituents, among others. The absurdization of events in the narrative “discourse” is presupposed by a set of semantic and pragmatic devices, in particular: the author’s assumed inability to create an event’s manoeuvring or to build the plot; the violation of the logic of the development of the plotline; making the modus and modality elements of the story weird; shifting points of view and their focuses, to name a few. The author’s intentional deviations within the “story” and the “discourse” of the belles‑lettres narrative cause communicative senses characteristic for an absurd type of writing: the senses of mental “charming”, which border on the reader’s cognitive “stupor”, as well as numerous senses of an evaluative and ludic character generated by the common “background” of the reader’s consciousness and borrowed, so to say, from “standard” belles‑lettres text types and narratives. The article outlines the perspectives of lingual‑narrative studies into weird (absurd, in particular) belles‑lettres texts.
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Authors and Affiliations

Флорій Бацевич
1
ORCID: ORCID

  1. Львівський університет імені Івана Франка
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Abstract

Metallurgical slags are an object of the increasing interest in terms of the possibility of their utilization, especially as materials used in the construction and road building industries, in the foundry industry for refining and purifying liquid alloys, the production of abrasives for surface treatment of remanufactured machine parts, as mine backfill materials. Metallurgical slags, in order to be used in foundry processes, should be characterized by the stability of the chemical composition. This paper presents the results of statistical analysis calculations, in which using a specific group f samples, knowing their chemical composition, the mean value Ā, variance Ϭ2, standard deviation Ϭ and the classical coefficient of variation V were determined. The research and its results report the amount of variation in considered components of the slags.
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Authors and Affiliations

Jacek Sitko
1
ORCID: ORCID

  1. Chair of Production Engineering, Silesian University of Technology, Roosevelt Str. 26, 48-000 Zabrze, Poland
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Abstract

The paper discusses a method of quantitative comparison of cylindricity profiles measured with different strategies. The method is based on applying so-called Legendre-Fourier coefficients. The comparison is carried out by computing the correlation coefficient between the profiles. It is conducted by applying a normalized cross-correlation function and it requires approximation of cylindrical surfaces using the Legendre-Fourier method. As the example two sets of measurement data are employed: the first from the CMM and the second one from the traditional radial measuring instrument. The measuring data are compared by analyzing the values of selected cylindricity parameters and calculating the coefficient of correlation between profiles.

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Authors and Affiliations

Krzysztof Stępień
Włodzimierz Makieła
Stanisław Adamczak
Dariusz Janecki
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Abstract

Twinned dendrites in Al-Zn alloy with high Zn content (40% wt.%) were successfully prepared by directional solidification. At different directional solidification rates (1000 and 1500 μm/s), microstructures and growth orientation variations of Al twinned dendrite and non-twinned dendrite were characterized. By using the inverted trapezoidal graphite sleeve at 1000 μm/s, Al twinned dendrite were formed to developed feather crystal structures in longitudinal section. Its primary and secondary twinned dendrite were grew along [110] direction. Moreover the deviation angle between [110] direction of Al twinned dendrite and the heat flow direction was about 27.15°. While not using the inverted trapezoidal graphite sleeve at 1000 and 1500 μm/s, Al dendrite was the non-twinned dendrite and the twinned dendrite was not appeared. The experimental results showed that the higher temperature gradient, a certain pulling rate and convection environment were the formation conditions of twinned dendrites.

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Authors and Affiliations

K. Gao
W. Song
L. Fan
Y. Ding
X. Guo
R. Zhang
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Abstract

This paper explores selected heuristics methods, namely CDS, Palmer’s slope index, Gupta’s

algorithm, and concurrent heuristic algorithm for minimizing the makespan in permutation

flow shop scheduling problem. Its main scope is to explore how different instances sizes

impact on performance variability. The computational experiment includes 12 of available

benchmark data sets of 10 problems proposed by Taillard. The results are computed and

presented in the form of relative percentage deviation, while outputs of the NEH algorithm

were used as reference solutions for comparison purposes. Finally, pertinent findings are

commented.

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Authors and Affiliations

Zuzana Soltysova
Pavol Semanco
Jan Modrak
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Abstract

The paper is concerned with one of the internal forces driving the progress of lyrical discourse. Its nature consists in that initially, some linguistic and/or cognitive deviation appears in the poem, and next the author undertakes a series of attempts at its adjustment or mitigation. More often than not these attempts are increasingly successful, but at some later point they, for various reasons, stop to be rewarding. This tends to happen either at the end of the text, where the most important truth is prototypically discovered, or immediately before the final fragment. In both cases, the completion of the relevant ‘adjustment’ theme plays a significant compositional role. Discussed at some length are the implications of our analysis for the theory of discourse relations. The bulk of the instances under examination are drawn from O. Mandelstam’s verse.
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Authors and Affiliations

Gennadij Zeldowicz
1
ORCID: ORCID

  1. Warszawa, Uniwersytet Warszawski
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Abstract

Production deviations have a remarkable effect on the radiated sound of electrical machines, introducing additional signal components besides the fundamental field waves which significantly change and enrich the subjectively perceived sound characteristic. In literature these harmonics are mainly traced back to dynamic eccentricity, which modulates the fundamental fieldwaves. In this paper a thorough mechanic and electromagnetic analysis of a modern, well-constructed traction drive (permanent magnet synchronous machine) is performed to showthat for this typical rotor configuration dynamic eccentricity is negligible. Instead, deviations in the rotor magnetization are shown to be the dominant cause for vibration harmonics.
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Bibliography

[1] Nahlaoui M.A., Steins H., Kulig S., Exnowski S., Comparison of numerically determined noise of a 290 kW induction motor using FEM and measured acoustic radiation, Archives of Electrical Engineering, vol. 62, pp. 195–207 (2013), DOI: 10.2478/aee-2013-0015.
[2] Gieras J.F., Wang C., Cho Lai J., Noise of polyphase electric motors, CRC Press Taylor and Francis Group (2006).
[3] Hu Y., Wei H., Chen H., Sun W., Zhao S., Li L., Vibration Study of Permanent Magnet Synchronous Motor Base on Static Eccentricity Model, 22nd International Conference on Electrical Machines and Systems (ICEMS), Harbin, China, pp. 1–5 (2019), DOI: 10.1109/ICEMS.2019.8922162.
[4] LiY.,Wu H.,Xu X., CaiY., Sun X., Analysis on electromechanical coupling vibration characteristics of in-wheel motor in electric vehicles considering air gap eccentricity, Archives of Electrical Engineering, vol. 5, pp. 851–862 (2019), DOI: 10.24425/bpasts.2019.130882.
[5] Lundin U., Wolfbrandt A., Method for Modeling Time-Dependent Nonuniform Rotor/Stator Configurations in Electrical Machines, IEEE Transactions on Magnetics, vol. 45, iss. 7, pp. 2976–2980 (2009), DOI: 10.1109/TMAG.2009.2015052.
[6] Zhang M., Macdonald A., Tseng K.-J., Burt G.M., Magnetic Equivalent Circuit Modeling for Interior Permanent Magnet Synchronous Machine under Eccentricity Fault, 48th International Universities’ Power Engineering Conference (UPEC), Dublin, Ireland, pp. 1–6 (2013), DOI: 10.1109/UPEC.2013.6715044.
[7] Ebrahimi B.M., Faiz J., Roshtkhari M.J., Static-, Dynamic-, and Mixed- Eccentricity Fault Diagnoses in Permanent-Magnet Synchronous Motors, IEEE Transactions on industrial electronics, vol. 56, no. 11, pp. 4727–4739 (2009), DOI: 10.1109/TIE.2009.2029577.
[8] Rosero J.A., Cusido J., Garcia A., Ortega J.A., Romeral L., Broken Bearings and Eccentricity Fault Detection for a Permanent Magnet Synchronous Motor, 32nd Annual Conference on IEEE Industrial Electronics (IECON), Paris, France, pp. 964–969 (2006), DOI: 10.1109/IECON.2006.347599.
[9] Ilamparithi T., Nandi S., Saturation independent detection of dynamic eccentricity fault in salient-pole synchronous machines, IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED), Valencia, Spain, pp. 336–341 (2013), DOI: 10.1109/DEMPED.2013.6645737. [10] Goktas T., Zafarani M., Akin B., Discernment of Broken Magnet and Static Eccentricity Faults in Permanent Magnet Synchronous Motors, IEEE Transactions on Energy Conversion, vol. 31, iss. 2, pp. 578–587 (2016).
[11] Coenen I., van der Giet M., Hameyer K., Manufacturing Tolerances: Estimation and Prediction of Cogging Torque Influenced by Magnetization Faults, IEEE Transactions on Magnetics, vol. 48, iss. 5, pp. 1932–1936 (2012), DOI: 10.1109/TMAG.2011.2178252.
[12] Gasparin L., Fiser R., Cogging torque sensitivity to permanent magnet tolerance combinations, Archives of Electrical Engineering, vol. 62, pp. 449–461 (2013), DOI: 10.2478/aee-2013-0036.
[13] International Organization for Standardization, ISO 1940-1: Mechanical vibration — Balance quality requirements for rotors in a constant (rigid) state, Geneva, Switzerland (2003).
[14] https://www.smalley.com/wave-springs/bearing-preload, accessed March 2020.
[15] Henrotte F., Felden M., van der Giet M., Hameyer K., Electromagnetic force computation with the Eggshell method, 14th International Symposium on Numerical Field Calculation in Electrical Engineering (IGTE), Graz, Austria (2010).
[16] Herold T., Franck D., Schröder M., Böhmer S., Hameyer K., Transientes Simulationsmodell für die akustische Bewertung elektrischer Antriebe, e & i Elektrotechnik und Informationstechnik, vol. 133, no. 2, pp. 55–64 (2016).

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Authors and Affiliations

Markus Jaeger
1
Pascal Drichel
2
Michael Schröder
1
Joerg Berroth
2
Georg Jacobs
2
Kay Hameyer
1
ORCID: ORCID

  1. Institute of Electrical Machines (IEM), RWTH Aachen University, Germany
  2. Institute of Systems Engineering and Machine Elements (MSE), RWTH Aachen University, Germany
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Abstract

In the current paper, the effect of tool wear for a constant period of time (360 s) during conventional and ultrasonic assisted machining of Inconel 718 is investigated in terms of cutting forces, temperature, and deviation measurements. For fixed process parameters turning experiments have been performed with and without the application of tangential vibration. Ultrasonic assisted turning (UAT) experiments have been compared with conventional turning (CT). The experimental results reveal that cutting forces and temperature increase linearly in the case of UAT whereas remaining constant in CT for a constant period of time. Besides the tool wear rate in the case of UAT is more than that in the CT.
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Authors and Affiliations

Srihari Dodla
1
ORCID: ORCID

  1. Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi-221005, India
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Abstract

Gear involute artifact (GIA) is a kind of calibration standard used for traceability of involute metrology. To machine GIAs with sub-micron profile form deviations, the effect on the involute profile deviations caused by the geometric deviations and 6-DoF errors of the machining tool based on the double roller-guide involute rolling generation mechanismwas analysed.At the same time, a double roller-guide involute lapping instrument and a lapping method for GIAs was proposed for lapping and in-situ measuring the gear involute artifacts. Moreover, a new GIA with three design base radii (50 mm, 100 mm, and 131 mm) was proposed for more efficient calibration and was machined with profile form deviations of 0.3 μm (within evaluation length of 38 mm, 68 mm, 80 mm, respectively, measured by the Chinese National Institute of Metrology), and the surface roughness Ra of the involute flanks was less than 0.05 μm. The research supports small-batch manufacturing for high-precision GIAs.
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Authors and Affiliations

Ming Ling
1
Siying Ling
2
Dianqing Yu
3
Zhihao Zhang
1
Fengtao Wang
2
Liding Wang
1

  1. Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116024, China
  2. Key Laboratory of Intelligent Manufacturing Technology of the Ministry of Education, Shantou University, Shantou 515063, China
  3. Liaoning Inspection, Examination & Certification Centre, Shenyang 110004, China
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Abstract

Geometric deviations of free-form surfaces are attributed to many phenomena that occur during machining, both systematic (deterministic) and random in character. Measurements of free-form surfaces are performed with the use of numerically controlled CMMs on the basis of a CAD model, which results in obtaining coordinates of discrete measurement points. The spatial coordinates assigned at each measurement point include both a deterministic component and a random component at different proportions. The deterministic component of deviations is in fact the systematic component of processing errors, which is repetitive in nature. A CAD representation of deterministic geometric deviations might constitute the basis for completing a number of tasks connected with measurement and processing of free-form surfaces. The paper presents the results of testing a methodology of determining CAD models by estimating deterministic geometric deviations. The research was performed on simulated deviations superimposed on the CAD model of a nominal surface. Regression analysis, an iterative procedure, spatial statistics methods, and NURBS modelling were used for establishing the model.

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Authors and Affiliations

Małgorzata Poniatowska
Andrzej Werner
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Abstract

This article presents a new efficient optimization technique namely the Multi- Objective Improved Differential Evolution Algorithm (MOIDEA) to solve the multiobjective optimal power flow problem in power systems. The main features of the Differential Evolution (DE) algorithm are simple, easy, and efficient, but sometimes, it is prone to stagnation in the local optima. This paper has proposed many improvements, in the exploration and exploitation processes, to enhance the performance of DE for solving optimal power flow (OPF) problems. The main contributions of the DE algorithm are i) the crossover rate will be changing randomly and continuously for each iteration, ii) all probabilities that have been ignored in the crossover process have been taken, and iii) in selection operation, the mathematical calculations of the mutation process have been taken. Four conflicting objective functions simultaneously have been applied to select the Pareto optimal front for the multi-objective OPF. Fuzzy set theory has been used to extract the best compromise solution. These objective functions that have been considered for setting control variables of the power system are total fuel cost (TFC), total emission (TE), real power losses (RPL), and voltage profile (VP) improvement. The IEEE 30-bus standard system has been used to validate the effectiveness and superiority of the approach proposed based on MATLAB software. Finally, to demonstrate the effectiveness and capability of the MOIDEA, the results obtained by this method will be compared with other recent methods.
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Authors and Affiliations

Murtadha Al-Kaabi
1
ORCID: ORCID
Jaleel Al Hasheme
2
ORCID: ORCID
Layth Al-Bahrani
3
ORCID: ORCID

  1. Ministry of Education Baghdad, Iraq
  2. University Politehnica of Bucharest, Bucharest, Romania
  3. Al-Mustansiriyah University Baghdad, Iraq

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