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Found 6319 publications

Corrosion Avoidance in the Metal Gate Industry Considering Sustainability

Publication Name: Chemical Engineering Transactions

Publication Date: 2021-01-01

Volume: 88

Issue: Unknown

Page Range: 1075-1080

Description:

Coating not cleaned up leads to massive emission worldwide, causing cancer and asthma. Coating gates to avoid corrosion needs to take place in nature. As a result, vast amounts of coating get sprayed out into nature, causing a significant sustainability issue. The industrial coating sector does not use protective equipment to save nature. The study aims to present a case study to minimise environmental pollution without increasing the cost of corrosion protection. The global cost related to corrosion has a significant burden on economies around the world – it costs approximately $2.5x1012 USD/y. It can be as high as 3.4 % of the GDP (2013). This cost has a significant impact on the efficiency of industries such as the automotive industry, industrial coatings and corrosion protection. Global demand for polyurethane coating materials will increase by 280 kt in 2022 (predictably). The volume of the solvent-based industrial coating consumption will grow significantly worldwide in the y 2021, predictably 1,400 Mt. In more detail, half of the coating is wasted, it drips onto the ground, gets into the air, so it causes pollution everywhere. The VOC (Volatile Organic Compounds) of the industrial coating pollutes the air, the living organism, and it can cause cancer, asthma and many other yet unknown health problems. The aim of this study is not only to introduce (based on data analysis) but to call attention to the environmental load originating from the industrial coating. In this study, the sustainability aspects of corrosion have been examined – especially in respect of the treatment of metal structures.

Open Access: Yes

DOI: 10.3303/CET2188179

Human factor aspects of situation awareness in autonomous cars – an overview of psychological approaches

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2021-01-01

Volume: 18

Issue: 7

Page Range: 7-24

Description:

The aim of the article is to give an overview of human factor research in psychology applicable to autonomous driving. The study is centered around situation awareness, a widely used concept in human factor research regarding the operation of automated and semi-automated systems (and communication between autonomous vehicles and humans). A proposal is put forward for structuring situation awareness requirements for autonomous driving, which could be a starting point for defining such requirements, and may foster a discussion on the issues associated with the human factor in relation to autonomous driving. Two models of human error (the SHELL model and the Swiss cheese model) are also introduced, one of which represents an integrated approach of error in situations that involve humans working with complex machinery or instruments, while the other represents a more superficial viewpoint on the multicausal nature of errors. The present overview can provide an appropriate basis for a discussion about the role of the driver in autonomous vehicles, and the place of human factor research in the emerging field of self-driving technology.

Open Access: Yes

DOI: 10.12700/APH.18.7.2021.7.1

Environmental effects, population genetic parameters, breeding value, phenotypic and genetic trend for age at first calving of limousin cows

Publication Name: Journal of Central European Agriculture

Publication Date: 2021-01-01

Volume: 22

Issue: 2

Page Range: 240-249

Description:

Some environmental effects, population genetic parameters, breeding value of Limousin breeding bulls, also phenotypic and genetic trends in the age at first calving (AFC) of cows between 1992 and 2013 were estimated. Data were served by the Limousin and Blonde d’Aquitaine Breeders Association, in Hungary. The study was extended to three herds and 1157 cows. GLM method was used for the study of different effects, the BLUP animal model for estimation of population genetic parameters and breeding values (BV), and one-way linear regression analysis for trend calculations. The overall mean value of the AFC was estimated to be 34.7±0.4 months. The contribution of the evaluated factors to the phenotype was as follows: herd 73.51%, birth year of cow 13.02%, sire 6.74%, birth season of cow 1.62%. The heritability of AFC proved to be low (h2 = 0.08±0.07 and h2 = 0.01±0.04). There were relatively small differences in the estimated BV of the studied sires for the AFC. Based on the phenotypic trend calculation, the AFC of cows decreased by an average of 0.33 months per year, however no significant change was found in the genetic trend during the study period.

Open Access: Yes

DOI: 10.5513/JCEA01/22.2.3161

Cross-country analysis of supply chain management drivers for small and medium-sized enterprises

Publication Name: Polish Journal of Management Studies

Publication Date: 2021-01-01

Volume: 23

Issue: 1

Page Range: 352-369

Description:

Supply Chain Management (SCM) drivers are the key factors in successful SCM strategy implementation. SMEs with limited resources need to focus on the top drivers to improve performance and competitiveness. The paper explores which driver factors have the largest importance according to the opinion of the top managers of SMEs. Two developing countries were compared which have different supply chain environments mainly due to their geographical structure. Information from top managers of 105 Hungarian and 124 Indonesian SMEs was collected using an online questionnaire. The data was analysed using statistical methods. This study is the first to rank SCM drivers in a quantitative study comparing SMEs in different supply chain environments. The findings reveal that from 22 driver factors both countries perceive the same top 10, however in a different ranking order. Improvement of customer satisfaction and information dissemination are the top two drivers, which are highly correlated.

Open Access: Yes

DOI: 10.17512/pjms.2021.23.1.22

Systematic Design and Evaluation of Energy-Efficient Alternatives of Heterogeneous Azeotropic Distillation: Furfural Case Study

Publication Name: Chemical Engineering Transactions

Publication Date: 2021-01-01

Volume: 88

Issue: Unknown

Page Range: 619-624

Description:

Separation of azeotropic mixtures receives special attention for their impact on various significant industrial processes. Because of the non-ideal behaviour of these mixtures, it is impossible to separate them by conventional distillation. Instead of a single distillation unit, a system of multiple operations is to be employed. Heterogeneous azeotropic distillation (HAD) is an example of this kind of systems, where entrainers are applied to modify the behaviour of the mixture. The selection of the best separation system is a key objective during the synthesis of the process network. However, synthesis of HAD is especially difficult because of the complex interaction between its continuous and discrete features. Therefore, traditional separation network synthesis tools are incapable of solving this problem. In this work, the properties of the ternary vapor-liquid-liquid equilibrium diagram are exploited for systematically identifying plausible operating units that perform the separation of the azeotrope. Subsequently, energy consumption of the entire network is estimated through rigorous simulation. The P-graph framework is employed to represent the system’s structure. Additionally, its combinatorial algorithms generate a rigorous superstructure for the synthesis problem, and the set of n-best designs that minimize energy consumption. The method is illustrated by synthesizing the dehydration of furfural through HAD. The results demonstrate that it constitutes a valuable tool for the designer by being effective in the systematic identification and assessment of HAD alternatives.

Open Access: Yes

DOI: 10.3303/CET2188103

Multiple hypothesis testing by unpaired samples for indexing changepoints in a road-induced vibration signal

No authors available

Publication Name: UPB Scientific Bulletin, Series D: Mechanical Engineering

Publication Date: 2021-01-01

Volume: 83

Issue: 3

Page Range: 17-28

Description:

Several methods have been developed for simulating non-stationary and non-Gaussian processes in packaging vibration testing, encompassing unique methods for the segmentation of road vehicle vibrations. However, only a limited number of those consider spectral characteristics. Thus, the current paper introduces a novel segmentation algorithm conducted in the time-frequency domain. The spectral characteristics obtained by short-time Fourier transform are compared by multiple hypothesis tests to find changepoints in a wheeled vehicle vibration sample. Different post hoc procedures are introduced against the inflating Type I. error.

Open Access: No

DOI: DOI not available

NVH characterization of a ladder-like welded structure using finite element analysis and experimental method

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

In vehicle industry, considering a chassis, the evaluation of the experimental modal analysis is usually done up to 80 Hz, since the modal density is increasing with frequency. In addition, the deviation between the measurement and simulation is getting more significant at higher frequencies. The purpose of this study is to extend the usable test range and to improve the accuracy of the results both in case of measurement and FE (Finite Element) simulation. Present paper introduces the vibrational characterization of a ladder-like welded structure. This test case represents a simplified model of a vehicle's frame consisting of rod-like elements with high stiffness, connected to each other in welded junctions. Although such simulational and experimental modal analysis procedures are widely used in practice, results can significantly change according to the used method and the fine-tuning of parameters. For this reason, a further goal is to find the best measurement and simulation technique for the given structure. During the FE analysis different modelling solutions and element types were compared. In order to discover the effect of the manufacturing inaccuracies, the same measurements were performed on two distinct, but theoretically identical samples. The influence of the experimental setup (e.g. excitation and fixing method) and settings were investigated as well. Finally, FE simulation and experimental results are compared using Frequency Response Functions.

Open Access: No

DOI: DOI not available

Development of tire-road noise measuring system

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

In vehicles there are 3 main noise sources: powertrain noise (e.g. engine, gear engagement or exhaust noise), aerodynamic noise (or wind noise), and the noise from the tire-road contact. The first two are traditionally in the primary focus of vehicle manufacturers, however, due to both the already made powerful developments and the spreading of electric vehicles, the rolling noise is gaining more and more attention during the vehicle development process. There are two major influencing factors of this noise source: tire (geometrical and material) characteristics and road (surface) characteristics. The separation of their contribution is not straightforward, investigated rarely, and the requirements of homologation standards do not expect it neither. However, if one would like to meet the new vehicle pass-by noise regulations, it is more and more inevitable to have a sophisticated break-down of rolling noise. A straightforward solution is the usage of a one-wheel testbench developed directly for acoustical measurements. Such design process is presented in this paper, where the most important requirements are: enabling the users to compare tires from acoustical aspect under totally objective conditions, modelling the typical conditions of vehicles and ensuring data for rolling noise simulations. One further functionality of the testbench is to reproduce the real rolling noise by mounting realistic road surface sections onto the superficies.

Open Access: No

DOI: DOI not available

Development of 1D and 3D acoustic simulation methods for transmission loss based on transfer matrix measurement results

No authors available

Publication Name: "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: Unknown

Description:

During the acoustical characterization of a component of a building, machine or vehicle, the normal incidence sound transmission loss is a major factor. Transmission loss simulation is also crucial in designing intake or exhaust elements, such as reflective mufflers. However, there is not enough information in the open literature about the applicable frequency ranges of experimental and 1- and 3D simulation methods. Therefore, the main purpose of this paper is to evaluate the frequency limits of computational and experimental transmission loss analyses of various reflective mufflers. For the validation two in-house impedance tube test benches were designed and multiple measurement setups were investigated. The combination of the four-pole matrix and the two-load methods was used during the experimental part of the study. In order to obtain appropriate transfer function results, distinct setups were evaluated, such as a low-frequency sound source with bigger tube diameter and a high-frequency sound source with smaller tube diameter. The low-frequency setup is suitable for the investigation of the system in the range of 30-500 Hz. The high-frequency setup is capable of measuring from 300 Hz to 2000 Hz, which is the upper frequency limit of the range of interest. Consequently, the in-house system is suitable for measuring the transmission loss in the 30-2000 Hz frequency range. 1D simulations were performed using Ricardo Wave software and 3D simulations were carried out in the STAR-CCM+ software. The upper cutoff frequency of 1D simulation method was determined to be 1500 Hz according to the correlation with the measurements. The frequency range of simulation could be extended up to 2000 Hz by employing 3D simulation for transmission loss calculations. This paper gives insights into the transmission loss measurements with the in-house system and the correlation analysis with different simulation methods.

Open Access: No

DOI: DOI not available