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In this context, this study aims to obtain information about the noise levels emitted to the environment by modeling the noise map of Dalaman Airport and correlating these noise values according to the Environmental Noise Directive (END) and World Health Organization (WHO) limits.

Dalaman Airport Aeronautical Information Publication and 2022 flight data from the airport were analyzed. The noise levels exposed to schools and health institutions were determined using the Cnossos–Eu calculation method.

Maximum noise levels were obtained as L_den 92.29 dB(A), L_day 85.24 dB(A), L_evening 89.00 dB(A) and L_night 85.23 dB(A) according to the noise indicators. Limit values recommended by the END and WHO according to noise indicator types and measurement results were correlated and evaluated.

In the noise modeling of Dalaman Airport, there has previously been no evaluation of the noise limits recommended according to END or WHO in the literature.

In recent years, in parallel with the increasing air traffic and the number of passengers in air transport, the number of people exposed to aircraft-induced noise has increased significantly. Especially people living in the areas close to the airports are affected by noise emission during the landing, take-off, taxi and ground operations. Negative effects of noise such as sleep disturbance, lack of concentration, anxiety and high blood pressure cardiac diseases were determined directly or indirectly for human health. For this reason, examining the noise effect caused by aircraft and determining the necessary measures to be taken is very important for the sustainable development of aviation. In the International Eskisehir Hasan Polatkan Airport (LTBY), this paper aims to calculate a noise mapping following international standards in line with the directives of the International Civil Aviation Organization (ICAO). Also, Annex 8, “Airworthiness of Aircrafts” and Annex 16, “Environmental Protection Volume 1 Aircraft Noise”, which were taken at the International Civil Aviation Convention, were proposed to determine the exposure caused by aircraft noise.

In this paper, noise levels for the day (07.00–19.00), evening (19.00–23.00) and night (23.00–07.00) period around LTBY were predicted and calculated by the use of the IMMI software according to the “ECAC Doc. 29-Interim” method for the prediction and computation of the aircraft noise.

According to the calculated/mapped values, in the 24 hours (Lden), the noise level is 65 dB (A) and above. In the day time zone, the noise level is 63 dB (A) and above. When the calculations for the evening time zone are examined, the noise level is above 58 dB (A). When the calculations for the night time frame are examined, it is calculated that there is no dwelling that is affected by the noise level above 53 dB (A).

Along with future improvements, it is recommended to be applied to other civil airports.

To the best of the authors’ knowledge, there is no previous research in the literature on aircraft noise mapping of LTBY. Also, unlike the software commonly used in other works in the literature, IMMI software was used in this study. Such investigations should be carried out in other civil airports in the coming years to struggle with noise emissions and noise control. If noise boundary values are exceeded, action plans should be developed for a sustainable aviation concept. Along with future improvements, it is recommended to be applied to other civil airports.

Electromagnetic noise of permanent magnet synchronous motor (PMSM) seriously affects the sound quality of electric vehicles (EVs). This paper aims to present a comprehensive process for the electromagnetic noise analysis and optimization of a water-cooled PMSM.

First, the noises of an eight-pole 48-slot PMSM in at speeds up to 10,000 rpm are measured. Furthermore, an electromagnetic-structural-acoustic model of the PMSM is established for multi-field coupling simulations of electromagnetic noises. Finally, the electromagnetic noise of the PMSM is optimized by using the multi-objective genetic algorithm, where a multi-objective function related to the slot width of PMSM stator is defined for radial electromagnetic force (REF) optimization.

The experimental results show that main electromagnetic noises are the 8n-order (n = 1, 2, 3, …) and 12-order noises. The simulated results show that the REFs are mainly generated by the 8n-order (n = 1, 2, 3, 4, 5, 6) vibrations, especially those of the 8th, 16th, 24th and 32th orders. The 12-order noise is a mechanical noise, which might be caused by the bearings and other structures of the PMSM. Comparing the simulated results before and after optimization, both the REFs and electromagnetic noises are effectively reduced, which suggests that an appropriate design of stator slot is important for reducing electromagnetic noise of the PMSM.

In view of applications, the methods proposed in this paper can be applied to other types of PMSM for generation mechanism analysis of electromagnetic noise, optimal design of PMSM and thereby noise improvement of EVs.

This article is a proposal and aims to be a first step to develop a method to evaluate and classify environmental noise, according to EN‐15251 and CR‐1752, in the built environment based on the percentage of dissatisfied related to the equivalent background noise level.

In the European guideline CR‐1752 and the standard EN‐15251 three categories of the indoor environment in buildings are prescribed (category A, B and C). In the recommendations, the limit whereby the percentage of dissatisfied should remain under varies in each category for both the thermal indoor environment and the air quality. The categories for noise and illumination criteria are not yet explicitly related to a percentage of dissatisfied.

Using the percentage of dissatisfied as the evaluation criterion, when related to the equivalent background noise, produces a more refined evaluation of comfort than an evaluation based on the percentage of seriously disturbed or the effects of sleep deprivation in relation to external noise. Furthermore, this corresponds to the European standards and recommendations concerning quality classification of the indoor environment, based on the percentage of dissatisfied.

Based on recent European undertakings concerning the development of categories for the indoor environment based on the percentage of dissatisfied, it is desirable to utilise these categories to noise aspects too, and to relate it to the equivalent background noise level.

The purpose of this paper is to present computer‐aided simultaneous signal and noise modeling and analysis for mm‐wave field‐effect transistors (FETs) based on scattering parameters approach.

A mm‐wave FET is modeled as three active‐coupled transmission lines, and the developed wave approach is applied to this model to calculate both signal and noise performances of the device.

The measurements show a good match with the calculated data from the point of view of both signal and noise performances of the device.

This CAD‐oriented analysis and modeling can be easily applied to the mm‐wave simulators to improve the simultaneous signal and noise optimization, modeling and analysis of mm‐wave devices, especially for traveling wave transistors in which the distributed model seems to be more exact than the usual lumped models. Also the proposed routine compared to the admittance approach is conceptually more compatible with scattering representations of active and passive circuits. The developed algorithm has been applied successfully to mm‐wave MESFETs and HEMTs.

The aim of this paper is to investigate the impacts of the noise from the diesel engine power generators used for production activities in an urban environment.

This study has used the Enterprise Edition of NoiseMap 2000 Version 2.7.1 to investigate the impacts of the noise from the diesel engines electric power generators used in a factory in Ikorodu, an urban environment in Lagos, Nigeria. Five sections of the factory with diesel engines electric power generators were considered. The immediate and distant environments covering about 10 km of the factory host environment were considered as receptors to the noise for this study.

It was found out that when all the generators operate simultaneously in the factory, the ambient noise was 30.0-152.5 dB(A) with the minimum contribution within the factory being 70.0-84.4 dB(A) and the maximum contribution of 57.2-70.8 dB(A) outside the factory fence line. Though the maximum noise is 152.5 dB(A), the maximum noise of 70.8 dB(A) beyond the fence line shows a compliance with 70 dB(A) industrial and commercial area limit but breaches the 45 dB(A) and 55 dB(A) residential area limit of the World Bank.

As much as it would be desirable ambient noise level could not be measured in all the receptors’ locations covered by the modeling. However, the capability of the modeling software adopted makes this to have no negative impact on the quality of the findings of this study.

The study will assist the public to determine the noise level safe region around diesel engine electric power generators.

The paper highlights the challenges in which ambient noise from the use of off-grid generators used for industrial purposes could pose to the neighboring receptor environments.