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Number of results: 158
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Abstract

The paper discusses a two-machine flow shop problem with minimization of the sum of tardiness costs, being a generalization of the popular NP-hard single-machine problem with this criterion. We propose the introduction of new elimination block properties allowing for accelerating the operation of approximate algorithms of local searches, solving this problem and improving the quality of solutions determined by them.

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Authors and Affiliations

W. Bożejko
M. Uchroński
M. Wodecki
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Abstract

Optimization of industrial processes such as manufacturing or processing of specific materials is a point of interest for many researchers, and its application can lead not only to speeding up the processes in question, but also to reducing the energy cost incurred during them. This article presents a novel approach to optimizing the spindle motion of a computer numeric control (CNC) machine. The proposed solution is to use deep learning with reinforcement to map the performance of the Reference Points Realization Optimization (RPRO) algorithm used in industry. A detailed study was conducted to see how well the proposed method performs the targeted task. In addition, the influence of a number of different factors and hyperparameters of the learning process on the performance of the trained agent was investigated. The proposed solution achieved very good results, not only satisfactorily replicating the performance of the benchmark algorithm, but also, speeding up the machining process and providing significantly higher accuracy.
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Authors and Affiliations

Dawid Kalandyk
Bogdan Kwiatkowski
ORCID: ORCID
Damian Mazur
ORCID: ORCID
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Abstract

The paper presents a new kind of vibrator, called the intelligent vibrator, which is an integrated set of two inert vibrators supplied by asynchronous squirrel-cage motors, equipped with digital control system, the readout system of the position of unbalanced masses, and inverter supply system. The paper presents a model of the prototype of the machine and exemplary run-times.
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Authors and Affiliations

Mariusz Giergiel
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Abstract

The paper discusses an occurrence or latent reactions in the direction perpendicular to the movement of the suspension systems in vibratory machines supported by parallel leaf springs. These reactions occur despite an apparent lack of any forces acting in that direction and may - for long machine bodies - reach values comparable with the exciting force of the vibrator. Analytical relationships allowing for estimation of the value of reactions were derived. The obtained results were verified by means of the Geometric Element Method as well as by the performed experiments.
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Authors and Affiliations

Jerzy Michalczyk
Piotr Czubak
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Abstract

castings. The possibility of reducing the total volume of machining allowances, reducing the wear of cutting tools, shortening machining time and eliminating idle machining passes was considered. The tests were carried out on two batches of castings supplied by two independent foundries. Casting geometry measurements were made using a structured light scanner. The analysis included machining with cemented carbide tools and tool ceramics at two machining centers: DMC200U and DMC270U. It has been shown that as a result of eliminating idle machining passes, it is possible to reduce machining time by 12% for the first and by 44% for the second casting supplier. The estimated annual savings for the production volume of 500 pcs of these castings can range from € 7388 to even € 23 346. The actual cost of cheaper casts was also calculated, taking into account the difference in machining cost resulting from larger machining allowances.
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Authors and Affiliations

Andrzej Gessner
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Mechanical Technology
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Abstract

This paper presents the results of experimental testing of parameters of the flow of an agitated liquid in a stirred tank with an eccentrically positioned shaft and with a Rushton turbine. The investigations were focused on the impact of the stirrer shaft shift in relation to the stirred tank vertical axis on the agitated liquid mean velocities and the liquid turbulent velocity fluctuations, as well as on the turbulence intensity in the tank. All the experiments were carried out in a stirred tank with the inner diameter of 286 mm and a flat bottom. The adopted values of the shaft eccentricity were zero (central position) and half the tank radius. The liquid flow instantaneous velocities were measured using laser Doppler anemometry.

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Authors and Affiliations

Jan Talaga
Piotr Duda
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Abstract

The world population, and thus the need for food, is increasing every day. This leads to the ultimate question of how to increase food production with limited time and scarce land. Another obstacle to meet the food demand includes the stresses a plant goes through. These may be abiotic or biotic, but the majority are biotic, i.e., plant diseases. The major challenge is to mitigate plant diseases efficiently, more quickly and with less manpower. Recently, artificial intelligence has turned to new frontiers in smart agricultural science. One novel approach in plant science is to detect and diagnose plant disease through deep learning and hyperspectral imaging. This smart technique is very advantageous for monitoring large acres of field where the availability of manpower is a major drawback. Early identification of plant diseases can be achieved through machine learning approaches. Advanced machine learning not only detects diseases but also helps to discover gene regulatory networks and select the genomic sequence to develop resistance in crop species and to mark pathogen effectors. In this review, new advancements in plant science through machine learning approaches have been discussed.
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Authors and Affiliations

Siddhartha Das
1
ORCID: ORCID
Sudeepta Pattanayak
2
ORCID: ORCID
Prateek Ranjan Behera
3

  1. Department of Plant Pathology, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakhemundi, Odisha, India
  2. Division of Plant Pathology, ICAR – Indian Agricultural Research Institute, New Delhi, India
  3. Department of Plant Pathology, College of Agriculture, Odisha University of Agriculture and Technology, Bhubaneswar, India
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Abstract

Knowledge about future traffic in backbone optical networks may greatly improve a range of tasks that Communications Service Providers (CSPs) have to face. This work proposes a procedure for long-term traffic forecasting in optical networks. We formulate a long-terT traffic forecasting problem as an ordinal classification task. Due to the optical networks’ (and other network technologies’) characteristics, traffic forecasting has been realized by predicting future traffic levels rather than the exact traffic volume. We examine different machine learning (ML) algorithms and compare them with time series algorithms methods. To evaluate the developed ML models, we use a quality metric, which considers the network resource usage. Datasets used during research are based on real traffic patterns presented by Internet Exchange Point in Seattle. Our study shows that ML algorithms employed for long-term traffic forecasting problem obtain high values of quality metrics. Additionally, the final choice of the ML algorithm for the forecasting task should depend on CSPs expectations.
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Authors and Affiliations

Krzysztof Walkowiak
1
Daniel Szostak
1
Adam Włodarczyk
1
Andrzej Kasprzak
1

  1. Wroclaw University of Science and Technology, Poland
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Abstract

This paper presents a new interim check device for coordinate measuring machines (CMMs) built from an AISI 1020 carbon steel bar with the incorporation of calibrated spheres. This artifact’s construction was made to make the interim checks of machines of this type faster and cheaper. Three devices were designed based on the ISO 10360-2 standard, the good practice guide No. 42 (NPL), and prominent authors’ research on the subject. The three options are presented in detail, but only one was built due to budget, size, and adaptability restrictions. An exploratory study was conducted to verify the device’s usability in two CMMs and concluded that the differences between the measurements are not significant. However, one machine had absolute variation values and a total standard deviation higher than the other, generating a larger expanded uncertainty.
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Authors and Affiliations

Rodrigo Schons Arenhart
1
Morgana Pizzolato
1
Fernanda Hänsch Beuren
2
Adriano Mendonça Souza
3
Leandro Cantorski da Rosa
1

  1. Federal University of Santa Maria, Department of Production Engineering and Systems, Roraima Avenue, 1000, Santa Maria, Brazil
  2. State University of Santa Catarina, Department of Industrial Technology, Fernando Hastreiter Street, São Bento do Sul, Brazil
  3. Federal University of Santa Maria, Statistics Department, Roraima Avenue, 1000, Santa Maria, Brazil
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Abstract

A laser measurement system for measuring straightness and parallelism error using a semiconductor laser was proposed. The designing principle of the developed system was analyzed. Addressing at the question of the divergence angle of the semiconductor laser being quite large and the reduction of measurement accuracy caused by the diffraction effect of the light spot at the longworking distance, the optical structure of the system was optimized through a series of simulations and experiments. A plano-convex lens was used to collimate the laser beam and concentrate the energy distribution of the diffraction effect. The working distance of the system was increased from 2.6 m to 4.6 m after the optical optimization, and the repeatability of the displacement measurement is kept within 2.2 m in the total measurement range. The performance of the developed system was verified by measuring the straightness of a machine tool through the comparison tests with two commercial multi-degree-of-freedom measurement systems. Two different measurement methods were used to verify the measurement accuracy. The comparison results show that during the straightness measurement of the machine tool, the laser head should be fixed in front of the moving axis, and the sensing part should move with the moving table of the machine tool. Results also show that the measurement error of the straightness measurement is less than 3 m compared with the commercial systems. The developed laser measurement system has the advantages of high precision, long working distance, low cost, and suitability for straightness and parallelism error measurement.
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Bibliography

[1] Schwenke, H., Knapp, W., & Haitjema, H. (2008). Geometric error measurement and compensation of machines – an update. CIRP Annals, 57(2), 660–675. https://doi.org/10.1016/j.cirp.2008.09.008
[2] Chen, Z., & Liu, X. (2020). A Self-adaptive interpolation method for sinusoidal sensors. IEEE Transactions on Instrumentation and Measurement, 69(10), 7675–7682. https://doi.org/10.1109/ TIM.2020.2983094
[3] Acosta, D., & Albajez, J. A. (2018). Verification of machine tools using multilateration and a geometrical approach. Nanomanufacturing and Metrology, 1(1), 39–44. https://doi.org/10.1007/ s41871-018-0006-y
[4] Chen, B. Y., Zhang, E. Z., & Yan, L. P. (2009). A laser interferometer for measuring straightness and its position based on heterodyne interferometry. Review of Scientific Instruments, 80(11), 115113. https://doi.org/10.1063/1.3266966
[5] Zhu, L. J., Li, L., Liu, & J. H. (2009). A method for measuring the guideway straightness error based on polarized interference principle. International Journal of Machine Tools and Manufacture, 49(3–4), 285–290. https://doi.org/10.1016/j.ijmachtools.2008.10.009
[6] Lin, S. T. (2001). A laser interferometer for measuring straightness. Optics & Laser Technology, 33(3), 195–199. https://doi.org/10.1016/S0030-3992(01)00024-X
[7] Jywe, W. Y., Liu, C. H., Shien, W. H., Shyu, L. H., & Fang, T. H. (2006). Development of a multidegree of freedoms measuring system and an error compensation technique for machine tools. Journal of Physics Conference Series, 48(1), 761–765. https://doi.org/10.1088/1742-6596/48/1/144
[8] Feng, Q. B., Zhang, B. & Cui, C. X. (2013). Development of a simple system for simultaneous measuring 6DOF geometric motion errors of a linear guide. Optics Express, 21(22), 25805–25819. https://doi.org/10.1364/OE.21.025805
[9] Liu, C. H., Chen, J. H., & Teng, Y. F. (2009). Development of a straightness measurement and compensation system with multiple right-angle reflectors and a lead zirconate titanate-based compensation stage. Review of Scientific Instruments, 80(11), 115105. https://doi.org/10.1063/1.3254018
[10] Fan, K. C. (2000). A laser straightness measurement system using optical fiber and modulation techniques. International Journal of Machine Tools Manufacture, 40(14), 2073–2081. https://doi.org/ 10.1016/S0890-6955(00)00040-7
[11] Hsieh, T. H., Chen, P. Y., & Jywe, W. Y. (2019). A geometric error measurement system for linear guideway assembly and calibration. Applied Sciences, 9(3), 574. https://doi.org/10.3390/app9030574
[12] Ni, J., & Huang, P. S. (1992). A multi-degree-of-freedom measuring system for CMM geometric errors. Journal of Manufacturing Science and Engineering, 114(3), 362–369. https://doi.org/10.1115/1.2899804
[13] Rahneberg, I., & Büchner, H. J. (2009). Optical system for the simultaneous measurement of twodimensional straightness errors and the roll angle. Proceedings of the International Society for Optics and Photonics, the Czech Republic, 7356. https://doi.org/10.1117/12.820634
[14] Chou, C., Chou, L. Y. & Peng, C. K. (1997). CCD-based CMM geometrical error measurement using Fourier phase shift algorithm. International Journal of Machine Tools and Manufacture, 37(5): 579–590. https://doi.org/10.1016/S0890-6955(96)00078-8
[15] Sun, C., Cai, S., & Liu, Y. (2020). Compact laser collimation system for simultaneous measurement of five-degree-of-freedom motion errors. Applied Sciences, 10(15), 5057. https://doi.org/10.3390/app10155057
[16] Huang, Y., Fan, Y., Lou, Z., Fan, K. C., & Sun, W. (2020). An innovative dual-axis precision level based on light transmission and refraction for angle measurement. Applied Sciences, 10(17), 6019. https://doi.org/10.3390/app10176019
[17] Born M., & Wolf E. (2013). Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light. Elsevier. https://www.sciencedirect.com/book/9780080264820/ principles-of-optic
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Authors and Affiliations

Peng Xu
1
Rui Jun Li
1
Wen Kai Zhao
1
Zhen Xin Chang
1
Shao Hua Ma
1
Kuang Chao Fan
1

  1. Hefei University of Technology, School of Instrument Science and Opto-Electronics Engineering, Hefei, China
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Abstract

Glucose concentration measurement is essential for diagnosis, monitoring and treatment of various medical conditions like diabetes mellitus, hypoglycemia, etc. This paper presents a novel image-processing and machine learning based approach for glucose concentration measurement. Experimentation based on Glucose oxidase - peroxidase (GOD/POD) method has been performed to create the database. Glucose in the sample reacts with the reagent wherein the concentration of glucose is detected using colorimetric principle. Colour intensity thus produced, is proportional to the glucose concentration and varies at different levels. Existing clinical chemistry analyzers use spectrophotometry to estimate the glucose level of the sample. Instead, this developed system uses simplified hardware arrangement and estimates glucose concentration by capturing the image of the sample. After further processing, its Saturation (S) and Luminance (Y) values are extracted from the captured image. Linear regression based machine learning algorithm is used for training the dataset consists of saturation and luminance values of images at different concentration levels. Integration of machine learning provides the benefit of improved accuracy and predictability in determining glucose level. The detection of glucose concentrations in the range of 10–400 mg/dl has been evaluated. The results of the developed system were verified with the currently used spectrophotometry based Trace40 clinical chemistry analyzer. The deviation of the estimated values from the actual values was found to be around 2- 3%.
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Authors and Affiliations

Angel Thomas
1
Sangeeta Palekar
1
Jayu Kalambe
1

  1. Shri Ramdeobaba College of Engineering & Management, India
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Abstract

In this paper, the performance of the Bayesian Optimization (BO) technique applied to various problems of microwave engineering is studied. Bayesian optimization is a novel, non-deterministic, global optimization scheme that uses machine learning to solve complex optimization problems. However, each new optimization scheme needs to be evaluated to find its best application niche, as there is no universal technique that suits all problems. Here, BO was applied to different types of microwave and antenna engineering problems, including matching circuit design, multiband antenna and antenna array design, or microwave filter design. Since each of the presented problems has a different nature and characteristics such as different scales (i.e. number of design variables), we try to address the question about the generality of BO and identify the problem areas for which the technique is or is not recommended.
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Authors and Affiliations

Michal Baranowski
1
ORCID: ORCID
Grzegorz Fotyga
1
ORCID: ORCID
Adam Lamecki
1 2
ORCID: ORCID
Michal Mrozowski
1
ORCID: ORCID

  1. Gdańsk University of Technology, Gdańsk, Gabriela Narutowicza 11/12 80-233, Poland
  2. EM Invent Sp. z o.o., Gdańsk, Trzy Lipy 3 80-172, Poland
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Abstract

The software for co-ordinate measuring machine (CMM) is used for approximating geometric elements in plane (2d) and in space (3d) by approximation algorithms when number of measuring points obtained is larger than the minimum number of points necessary for element definition. Orthogonal regression methods are discussed in this paper. For 2d and 3d cases and they are compared with methods for defining straight line using linear regression. The advantage of orthogonal regression over linear regression is shown by comparing variance of measuring point displacement from both approximation line types.Algorithms for orthogonal regression make it possible to determine optimum position of a straight line for which value of variance of point distance from the line is the lowest possible. The tests have been performed on the Carl Zeiss CMM.
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Authors and Affiliations

Ryszard Filipowski
Lucjan Dąbrowski
Józef Zawora
Ryszard Kossowski
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Abstract

The paper presents a study of Rotary Electrical Discharge Machining (REDM) process. In REDM, simple shaped cylindrical electrodes are used to generate 3D complex shapes. A theoretical model of machining process is described, which takes into consideration the effect of tool electrode wear on machined surface profile. The software for computer simulation of REDM has been developed. In the paper, the effects of machining parameters on shape error of machined surface are discussed. Results of computer simulation have been confirmed in experimental practice. The simulation model for NC contouring REDM may also be applied to solving numerical control problems and optimization of tool electrode path.
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Authors and Affiliations

Jerzy Kozak
Zbigniew Gulbinowicz
Dorota Gulbinowicz
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Abstract

The cost overrun in road construction projects in Iraq is one of the major problems that face the construction of new roads. To enable the concerned government agencies to predict the final cost of roads, the objective this paper suggested is to develop an early cost estimating model for road projects using a support vector machine based on (43) sets of bills of quantity collected in Baghdad city in Iraq. As cost estimates are required at the early stages of a project, consideration was given to the fact that the input data for the support vector machine model could be easily extracted from sketches or the project’s scope definition. The data were collected from contracts awarded by the Mayoralty of Baghdad for completed projects between 2010–2013. Mathematical equations were constructed using the Support Vector Machine Algorithm (SMO) technique. An average of accuracy (AA) (99.65%) and coefficient of determination (R2) (97.63%) for the model was achieved by the created prediction equations.
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Authors and Affiliations

Musaab Falih Hasan
1
ORCID: ORCID
Oday Hammody
2
ORCID: ORCID
Khaldoon Satea Albayati
3
ORCID: ORCID

  1. General Directorate of Education Baghdad Rusafa First, Ministry of Education, Iraq
  2. Civil Engineering Department, University of Technology, Baghdad, Iraq
  3. Iraqi Reinsurance Company, Ministry of Finance, Iraq
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Abstract

The paper presents an off-line application that determines the maximum accuracy of the reference points for the given dynamics parameters of a CNC machine. These parameters are maximum speed, acceleration, and JERK. The JERK parameter determines the rate of change of acceleration. These parameters are defined for each working axis of the machine. The main achievement of the algorithm proposed in the article is the determination of the smallest error specified for each reference point resulting from the implemented G-code for the considered dynamic parameters of the CNC machine. The solutions to this problem in industry consider the improvement in the accuracy of hitting the reference points, but they do not provide information on whether the obtained solution is optimal for such parameters of the machine dynamics. The algorithm makes the accuracy dependent on the adopted dynamic parameters of the machine and the parameters of the PLC controller used in the CNC machine.
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Authors and Affiliations

Bogdan Kwiatkowski
1
ORCID: ORCID
Tadeusz Kwater
2
ORCID: ORCID
Damian Mazur
1
ORCID: ORCID
Jacek Bartman
3
ORCID: ORCID

  1. Department of Electrical and Computer Engineering Fundamentals, Rzeszow University of Technology, ul. W. Pola 2, 35-959 Rzeszow, Poland
  2. Institute of Technical Engineering, State University of Technology and Economics in Jaroslaw, ul. Czarnieckiego 16, 37-500 Jaroslaw, Poland
  3. University of Rzeszow, ul. Rejtana 16C, Rzeszow, Poland
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Abstract

Artificial Intelligence begins to play an increasingly important role in medicine, in particular in diagnostics, therapy selection and drug design. This article shows how the latest machine learning algorithms support the work of physicians and pharmacists. However, the effective implementation of Artificial Intelligence methods in everyday medical practice requires overcoming a number of barriers. These challenges are discussed in the article. The objectives and functioning of the Artificial Intelligence Center in Medicine of the Medical University of Bialystok were also discussed, as an example of Polish contribution to the development of the latest computer algorithms supporting diagnostics and therapy.
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Authors and Affiliations

Konrad Wojdan
1 2
Marcin Moniuszko
3

  1. Politechnika Warszawska, Instytut Techniki Cieplnej
  2. Transition Technologies Science sp. z o.o.
  3. Uniwersytet Medyczny w Białymstoku
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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 this paper, the secure low-power Internet of Things (IoT) transmission methods for encryption and digital signature are presented. The main goal was to develop energyefficient method to provide IoT devices with data confidentiality, integrity, and authenticity. The cryptograph energy efficient and security algorithms modifications for IoT domain were made. The novelty in our solution is the usage of encryption method popular in the image processing in the domain of the Internet of Things. Proposed modification improves immunity for the brute-force and plain-text attacks. Furthermore, we propose the modifications for hash calculation method to transform it into digital signature calculation method that is very sensitive to input parameters. The results indicate low energy consumption of both methods, however it varies significantly depending on the architecture of the devices.
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Authors and Affiliations

Bartosz Kościug
1
Piotr Bilski
1
ORCID: ORCID

  1. The Faculty of Electronics and Information Technology on Warsaw University of Technology, Warsaw, Poland
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Abstract

This issue is a typical NP-hard problem for an unrelated parallel machine scheduling problem with makespan minimization as the goal and no sequence-related preparation time. Based on the idea of tabu search (TS), this paper improves the iterative greedy algorithm (IG) and proposes an IG-TS algorithm with deconstruction, reconstruction, and neighborhood search operations as the main optimization process. This algorithm has the characteristics of the strong capability of global search and fast speed of convergence. The warp knitting workshop scheduling problem in the textile industry, which has the complex characteristics of a large scale, nonlinearity, uncertainty, and strong coupling, is a typical unrelated parallel machine scheduling problem. The IG-TS algorithm is applied to solve it, and three commonly used scheduling algorithms are set as a comparison, namely the GA-TS algorithm, ABC-TS algorithm, and PSO-TS algorithm. The outcome shows that the scheduling results of the IG-TS algorithm have the shortest manufacturing time and good robustness. In addition, the production comparison between the IG-TS algorithm scheduling scheme and the artificial experience scheduling scheme for the small-scale example problem shows that the IG-TS algorithm scheduling is slightly superior to the artificial experience scheduling in both planning and actual production. Experiments show that the IG-TS algorithm is feasible in warp knitting workshop scheduling problems, effectively realizing the reduction of energy and the increase in efficiency of a digital workshop in the textile industry.
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Authors and Affiliations

Xinfu Chi
1
ORCID: ORCID
Shijing Liu
1
Ce Li
1

  1. Dong Hua University, College of Mechanical Engineering, Shanghai 201620, China
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Abstract

This article presents results of the numerical analysis of the interaction between heavy caterpillar tracks system and subsoil. The main goal of the article is to present an algorithm to design working platforms - temporary structures enabling the work of heavy construction equipment on weak subsoils. A semi-analytical method is based on the results of the numerical analysis performed with use of the finite element method (FE software ZSoil.PC [12]). The calculations were carried out for the piling rig machine - Bauer BH20H (BT60). Three ground models were adopted: Model 1: one layer - weak cohesive soil (clay); Model 2: two layers: weak cohesive soil (clay) and cohesionless working platform (medium sand); Model 3: one layer: strong cohesionless subsoil (medium sand). The following problems were solved: I) entry of the machine on the ground with various geotechnical parameters under each caterpillar tracks II) detection of the maximum permissible angle of ground slope.

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Authors and Affiliations

A. Urbański
M. Richter
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Abstract

Structural health monitoring (SHM) of bridges is constantly upgraded by researchers and bridge engineers as it directly deals with bridge performance and its safety over a certain time period. This article addresses some issues in the traditional SHM systems and the reason for moving towards an automated monitoring system. In order to automate the bridge assessment and monitoring process, a mechanism for the linkage of Digital Twins (DT) and Machine Learning (ML), namely the Support Vector Machine (SVM) algorithm, is discussed in detail. The basis of this mechanism lies in the collection of data from the real bridge using sensors and is providing the basis for the establishment and calibration of the digital twin. Then, data analysis and decision-making processes are to be carried out through regression-based ML algorithms. So, in this study, both ML brain and a DT model are merged to support the decision-making of the bridge management system and predict or even prevent further damage or collapse of the bridge. In this way, the SHM system cannot only be automated but calibrated from time to time to ensure the safety of the bridge against the associated damages.
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Authors and Affiliations

Asseel Za'al Ode Al-Hijazeen
1
ORCID: ORCID
Muhammad Fawad
1 2
ORCID: ORCID
Michael Gerges
3
ORCID: ORCID
Kalman Koris
1
ORCID: ORCID
Marek Salamak
2
ORCID: ORCID

  1. Budapest University of Technology and Economics, Faculty of Civil Engineering, Muegyetem rkp. 3, 1111 Budapest, Hungary
  2. Silesian University of Technology, Faculty of Civil Engineering, ul. Akademicka 2A, 44-100 Gliwice, Poland
  3. University of Wolverhampton, Wulfruna St, Wolverhampton WV1 1LY, the United Kingdom
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Abstract

This is a modest endeavour written from an engineering perspective by a nonphilosopher to set things straight if somewhat roughly: What does artificial intelligence boil down to? What are its merits and why some dangers may stem from its development in this time of confusion when, to quote Rémi Brague: “From the point of view of technology, man appears as outdated, or at least superfluous”?

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Authors and Affiliations

Jacek Koronacki
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Abstract

The availability of cheap and widely applicable person identification techniques is essential due to a wide-spread usage of online services. The dynamics of typing is characteristic to particular users, and users are hardly able to mimic the dynamics of typing of others. State-of-the-art solutions for person identification from the dynamics of typing are based on machine learning. The presence of hubs, i.e., few instances that appear as nearest neighbours of surprisingly many other instances, have been observed in various domains recently and hubness-aware machine learning approaches have been shown to work well in those domains. However, hubness has not been studied in the context of person identification yet, and hubnessaware techniques have not been applied to this task. In this paper, we examine hubness in typing data and propose to use ECkNN, a recent hubness-aware regression technique together with dynamic time warping for person identification. We collected time-series data describing the dynamics of typing and used it to evaluate our approach. Experimental results show that hubness-aware techniques outperform state-of-the-art time-series classifiers.

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Authors and Affiliations

Krisztian Buza
Dora Neubrandt

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