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1 – 10 of 113
Open Access
Article
Publication date: 30 March 2022

Mariusz Baranski, Wojciech Szelag and Wieslaw Lyskawinski

This paper aims to elaborate the method and algorithm for the analysis of the influence of temperature on back electromotive force (BEMF) waveforms in a line start permanent…

Abstract

Purpose

This paper aims to elaborate the method and algorithm for the analysis of the influence of temperature on back electromotive force (BEMF) waveforms in a line start permanent magnet synchronous motor (LSPMSM).

Design/methodology/approach

The paper presents a finite element analysis of temperature influence on BEMF and back electromotive coefficient in a LSPMSM. In this paper, a two-dimensional field model of coupled electromagnetic and thermal phenomena in the LSPMSM was presented. The influence of temperature on magnetic properties of the permanent magnets as well as on electric and thermal properties of the materials has been taken into account. Simulation results have been compared to measurements. The selected results have been presented and discussed.

Findings

The simulations results are compared with measurements to confirm the adequacy of this approach to the analysis of coupled electromagnetic-thermal problems.

Originality/value

The paper offers appropriate author’s software for the transient and steady-state analysis of coupled electromagnetic and thermal problems in LSPMS motor.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 4 January 2024

Chang Liu, Shiwu Yang, Yixuan Yang, Hefei Cao and Shanghe Liu

In the continuous development of high-speed railways, ensuring the safety of the operation control system is crucial. Electromagnetic interference (EMI) faults in signaling…

Abstract

Purpose

In the continuous development of high-speed railways, ensuring the safety of the operation control system is crucial. Electromagnetic interference (EMI) faults in signaling equipment may cause transportation interruptions, delays and even threaten the safety of train operations. Exploring the impact of disturbances on signaling equipment and establishing evaluation methods for the correlation between EMI and safety is urgently needed.

Design/methodology/approach

This paper elaborates on the necessity and significance of studying the impact of EMI as an unavoidable and widespread risk factor in the external environment of high-speed railway operations and continuous development. The current status of research methods and achievements from the perspectives of standard systems, reliability analysis and safety assessment are examined layer by layer. Additionally, it provides prospects for innovative ideas for exploring the quantitative correlation between EMI and signaling safety.

Findings

Despite certain innovative achievements in both domestic and international standard systems and related research for ensuring and evaluating railway signaling safety, there’s a lack of quantitative and strategic research on the degradation of safety performance in signaling equipment due to EMI. A quantitative correlation between EMI and safety has yet to be established. On this basis, this paper proposes considerations for research methods pertaining to the correlation between EMI and safety.

Originality/value

This paper overviews a series of methods and outcomes derived from domestic and international studies regarding railway signaling safety, encompassing standard systems, reliability analysis and safety assessment. Recognizing the necessity for quantitatively describing and predicting the impact of EMI on high-speed railway signaling safety, an innovative approach using risk assessment techniques as a bridge to establish the correlation between EMI and signaling safety is proposed.

Details

Railway Sciences, vol. 3 no. 1
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 15 July 2022

Xuwei Jin, Shize Huang, Xiaowen Liu, Jing Zhou, Jinzhe Qin, Decun Dong and Xingying Li

Electromagnetic interference (EMI) on communication systems of unban rail transit can hardly be clarified because of complicated factors around railways. This paper aims to target…

Abstract

Purpose

Electromagnetic interference (EMI) on communication systems of unban rail transit can hardly be clarified because of complicated factors around railways. This paper aims to target this issue and extend experimental and theoretical analysis.

Design/methodology/approach

This paper take the Nanjing Dashengguan Bridge as an example, because it carries the most tracks in the world and bears three kinds of trains running through, providing a perfect complex environment. First, it investigates the three communication systems, terrestrial trunked radio, communications-based train control (CBTC) and passenger information system (PIS) that Nanjing Metro uses, and select appropriate devices accordingly. Second, it establishes a system level platform and conduct three tests to analyze their respective operating principles and performance difference under common electromagnetic environments. Third, it adopts theoretical formula to verify test results.

Findings

The experiment results and theoretical analysis mutually corroborate each other and present practical recommendations: an 8 m or more distance between two tracks will ensure no obvious EMI created by a passing train on communication systems; two certain communication systems should not share the same frequency band; interference level is more related to field strength than weathers and building materials; and CBTC DSSS waveguide mode as well as PIS LTE mode are preferred.

Originality/value

This research also provides a practical method of investigating EMI for other complex situations.

Details

Smart and Resilient Transport, vol. 4 no. 2
Type: Research Article
ISSN: 2632-0487

Keywords

Open Access
Article
Publication date: 15 January 2020

Wanna Chongchitpaisan, Phongtape Wiwatanadate, Assawin Narkpongphun, Surat Tanprawate and Nipapon Siripon

Adolescents being in a stage of growth need good sleep, but, today, they suffer from sleep deprivation due to such extrinsic factor as a smartphone which they enjoy spending time…

2444

Abstract

Purpose

Adolescents being in a stage of growth need good sleep, but, today, they suffer from sleep deprivation due to such extrinsic factor as a smartphone which they enjoy spending time using the device. However, the effects of smartphone output power (SOP) on the duration of good sleep remains unclear. The purpose of this paper is to investigate the correlation of the SOP and sleep loss in high school students.

Design/methodology/approach

The time-series study was conducted among 145 high school students in Chiang Mai Province who completed a sleep diary which applied by the Pittsburg Sleep Quality Index. The SOP was corrected by a smartphone application and transmitted by e-mail to a researcher every day. The completed data set contains 12,969 entries. Headache, anxiety and depression were also assessed. Data were analyzed using the generalized estimating equation adjusted for demographic data, smartphone use and other factors.

Findings

Most of the study subjects are female, 17.4 years old on average. The prevalence of sleep loss (<8 h) was 52.9 percent with averagely 7.4 ±1.7 h of sleep duration and poor sleep at 32.1 percent. Anxiety, depression, headache had relationships with sleep loss. The daily dose, evening and nocturnal SOP in the range of ≥ 2.00 × 10‒5 mW had stronger relationships with sleep loss than their effects in the range of ≤ 1.79 × 10‒5 mW (ORadj1.32; 95% CI: 1.26–1.76, ORadj1.34; 95% CI: 1.07–1.17 and ORadj1.41; 95% CI: 1.07–1.17, respectively). Meanwhile, morning Lag_2 and daytime Lag_1 in the range of ≥ 2.00 × 10‒5 mW appeared to have a strong relationship with sleep loss (ORadj1.60; 95% CI: 1.26–1.76, ORadj1.36; 95% CI: 1.07–1.17). The relationship between Lag_4 daily dose and sleep loss took the form of a reverse dose-response.

Originality/value

Sleep loss in adolescents has an increasing trend of prevalence and has been found to be correlated with the highest SOP group (≥ 2.00 × 10‒5 mW range). These results confirmed that increased and longer smartphone use result in reduced sleep time. This causes them to be exposed to smartphone electromagnetic radiation and smartphone screen lighting. This disturbs brain waves and nervous system controlling sleep balance mechanisms. The findings recommended parents setting time and boundaries around technology use at home to reduce contact with electromagnetic radiation and smartphone screen lighting, thereby increasing sleeping time in order to create good sleep quality.

Details

Journal of Health Research, vol. 34 no. 4
Type: Research Article
ISSN: 2586-940X

Keywords

Open Access
Article
Publication date: 8 August 2019

Wanna Chongchitpaisan, Phongtape Wiwatanadate, Surat Tanprawate, Assawin Narkpongphun and Nipapon Siripon

Nocturnal headaches among adolescents were reported to be increased with the development of modern technology. The purpose of this paper is to investigate the smartphone…

1330

Abstract

Purpose

Nocturnal headaches among adolescents were reported to be increased with the development of modern technology. The purpose of this paper is to investigate the smartphone electromagnetic radiation related to nocturnal headaches among high school students.

Design/methodology/approach

The time series study of all 12,969 records from 145 high school students Chiang Mai Province was selected from the population in the first phase by setting criteria. The samples completed a headache diary utilizing a smartphone application. The smartphone output power (SOP) was measured and recorded by the smartphone application and transmitted by e-mail to a researcher. The smartphone use, sleep quality, anxiety and depression also were assessed. Data were analyzed using Generalized Estimating Equation adjusting for demographic data, smartphone use, and sleep quality and otherwise.

Findings

The resulted showed the prevalence of repeated headaches to be 13.4 percent, nocturnal headache only 5.3 percent and the strongest effect of day time SOP at a 1.80–1.99×10−5 mW range on nocturnal headaches (ORadj5.18; 95% CI: 3.44–7.81). Meanwhile, Lag_6 of daily SOP exposure produced a nocturnal headache effect in a reverse dose-response manner. Furthermore, the nocturnal headache also had the strongest association with age, internet use and device brand (ORadj2.33; 95% CI: 1.08–5.05, ORadj2.14; 95% CI: 1.07–4.2 and ORadj1.68; 95% CI: 1.1–2.4).

Originality/value

The electromagnetic radiation from a smartphone is the environmental variables influences on headache. The results suggested that there should be limited times for smartphone use and older age to start using a smartphone to prevent headache attacks at night.

Details

Journal of Health Research, vol. 33 no. 6
Type: Research Article
ISSN: 2586-940X

Keywords

Open Access
Article
Publication date: 5 January 2022

Alex Mason, Dmytro Romanov, L. Eduardo Cordova-Lopez, Steven Ross and Olga Korostynska

Modern meat processing requires automation and robotisation to remain sustainable and adapt to future challenges, including those brought by global infection events. Automation of…

2213

Abstract

Purpose

Modern meat processing requires automation and robotisation to remain sustainable and adapt to future challenges, including those brought by global infection events. Automation of all or many processes is seen as the way forward, with robots performing various tasks instead of people. Meat cutting is one of these tasks. Smart novel solutions, including smart knives, are required, with the smart knife being able to analyse and predict the meat it cuts. This paper aims to review technologies with the potential to be used as a so-called “smart knife” The criteria for a smart knife are also defined.

Design/methodology/approach

This paper reviews various technologies that can be used, either alone or in combination, for developing a future smart knife for robotic meat cutting, with possibilities for their integration into automatic meat processing. Optical methods, Near Infra-Red spectroscopy, electrical impedance spectroscopy, force sensing and electromagnetic wave-based sensing approaches are assessed against the defined criteria for a smart knife.

Findings

Optical methods are well established for meat quality and composition characterisation but lack speed and robustness for real-time use as part of a cutting tool. Combining these methods with artificial intelligence (AI) could improve the performance. Methods, such as electrical impedance measurements and rapid evaporative ionisation mass spectrometry, are invasive and not suitable in meat processing since they damage the meat. One attractive option is using athermal electromagnetic waves, although no commercially developed solutions exist that are readily adaptable to produce a smart knife with proven functionality, robustness or reliability.

Originality/value

This paper critically reviews and assesses a range of sensing technologies with very specific requirements: to be compatible with robotic assisted cutting in the meat industry. The concept of a smart knife that can benefit from these technologies to provide a real-time “feeling feedback” to the robot is at the centre of the discussion.

Details

Sensor Review, vol. 42 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Open Access
Article
Publication date: 13 October 2023

Hongmei Li, Junling Shi, Xiangdong Li, Junbo Zhang and Yunlong Chen

High-speed maglev technology can address the issues of adhesion, friction, vibration and high-speed current collection in traditional wheel-rail systems, making it an important…

507

Abstract

Purpose

High-speed maglev technology can address the issues of adhesion, friction, vibration and high-speed current collection in traditional wheel-rail systems, making it an important direction for the future development of high-speed rail technology.

Design/methodology/approach

This paper elaborates on the demand and significance of developing high-speed maglev technology worldwide and examines the current status and technological maturity of several major high-speed maglev systems globally.

Findings

This paper summarizes the challenges in the development of high-speed maglev railways in China. Based on this analysis, it puts forward considerations for future research on high-speed maglev railways.

Originality/value

This paper describes the development status and technical maturity of several major high-speed maglev systems in the world for the first time, summarizes the existing problems in the development of China's high-speed maglev railway and on this basis, puts forward the thinking of the next research of China's high-speed maglev railway.

Details

Railway Sciences, vol. 2 no. 3
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 28 September 2023

Jonas Bundschuh, M. Greta Ruppert and Yvonne Späck-Leigsnering

The purpose of this paper is to present the freely available finite element simulation software Pyrit.

Abstract

Purpose

The purpose of this paper is to present the freely available finite element simulation software Pyrit.

Design/methodology/approach

In a first step, the design principles and the objective of the software project are defined. Then, the software’s structure is established: The software is organized in packages for which an overview is given. The structure is based on the typical steps of a simulation workflow, i.e., problem definition, problem-solving and post-processing. State-of-the-art software engineering principles are applied to ensure a high code quality at all times. Finally, the modeling and simulation workflow of Pyrit is demonstrated by three examples.

Findings

Pyrit is a field simulation software based on the finite element method written in Python to solve coupled systems of partial differential equations. It is designed as a modular software that is easily modifiable and extendable. The framework can, therefore, be adapted to various activities, i.e., research, education and industry collaboration.

Research limitations/implications

The focus of Pyrit are static and quasistatic electromagnetic problems as well as (coupled) heat conduction problems. It allows for both time domain and frequency domain simulations.

Originality/value

In research, problem-specific modifications and direct access to the source code of simulation tools are essential. With Pyrit, the authors present a computationally efficient and platform-independent simulation software for various electromagnetic and thermal field problems.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 27 July 2022

Sami Barmada, Alessandro Formisano, Dimitri Thomopulos and Mauro Tucci

This study aims to investigate the possible use of a deep neural network (DNN) as an inverse solver.

Abstract

Purpose

This study aims to investigate the possible use of a deep neural network (DNN) as an inverse solver.

Design/methodology/approach

Different models based on DNNs are designed and proposed for the resolution of inverse electromagnetic problems either as fast solvers for the direct problem or as straightforward inverse problem solvers, with reference to the TEAM 25 benchmark problem for the sake of exemplification.

Findings

Using DNNs as straightforward inverse problem solvers has relevant advantages in terms of promptness but requires a careful treatment of the underlying problem ill-posedness.

Originality/value

This work is one of the first attempts to exploit DNNs for inverse problem resolution in low-frequency electromagnetism. Results on the TEAM 25 test problem show the potential effectiveness of the approach but also highlight the need for a careful choice of the training data set.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 16 February 2022

Karl Hollaus, Susanne Bauer, Michael Leumüller and Christian Türk

Cables are ubiquitous in electronic-based systems. Electromagnetic emission of cables and crosstalk between wires is an important issue in electromagnetic compatibility and is to…

Abstract

Purpose

Cables are ubiquitous in electronic-based systems. Electromagnetic emission of cables and crosstalk between wires is an important issue in electromagnetic compatibility and is to be minimized in the design phase. To facilitate the design, models of different complexity and accuracy, for instance, circuit models or finite element (FE) simulations, are used. The purpose of this study is to compare transmission line parameters obtained by measurements and simulations.

Design/methodology/approach

Transmission line parameters were determined by means of measurements in the frequency and time domain and by FE simulations in the frequency domain and compared. Finally, a Spice simulation with lumped elements was performed.

Findings

The determination of the effective permittivity of insulated wires seems to be a key issue in comparing measurements and simulations.

Originality/value

A space decomposition technique for a guided wave on an infinite configuration with constant cross-section has been introduced, where an analytic representation in the direction of propagation is used, and the transversal fields are approximated by FEs.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 113