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Experimental comparison of field and accelerated random vertical vibration levels of stacked packages for small parcel delivery shipments

Péter Böröcz Bence Molnar

Publication Name: Applied Sciences Switzerland

Publication Date: 2021-04-01

Volume: 11

Issue: 7

Page Range: Unknown

Description:

In the last decade, there has been a significant increase in parcel delivery shipments all over the world due to online stores and consumer demand to receive the products in a shorter period of time. It is especially true when situations like COVID-19 limits personal purchases in shopping malls as well as grocery and pharmaceutical stores. This often means that courier operators try to deliver packages utilizing vehicles with racks or shelves, which during the COVID-19 epidemic are not there anymore. This study measured the vertical vibration levels that occur in stacked parcels during express delivery versus the simulation technique in the laboratory. The goal of this paper was to measure and compare the vibration levels between laboratory practice and field transportation. For the measurement a three-layer stacked unit was built to observe the vibration levels on different road conditions in a parcel delivery vehicle and ASTM vibration profile (ASTM International). Then the measured acceleration-time data were analyzed in terms of power spectral densities (PSD) and the presented statistical data provided an understanding of the variability of intensity in different levels in stacked unit. The results showed that the vibration level increases in the stacked load upwards and with worse road conditions, but even in the worst case it did not reach those vibration levels that the laboratory test showed. Moreover, the layers of the stacked unit are in out-of-phase motion in the field, while the stacked unit in the vibration simulation usually is in-phase motion. Results indicate that the proposed vibration simulation does not correlate well with typical field vibration. This is fundamentally true as during a forced vibration created by a single-axis shaker, do not account for additional inputs occurring simultaneously creating an off-balance to the loads and as a result are less severe than simulated conditions. These findings are limited to single axis vibration simulation and unsecured loads.

Open Access: Yes

DOI: 10.3390/app11072927

Measurement and analysis of industrial forklifts vibration levels for unit load testing purposes

Laszlo Horvath Péter Böröcz Yu Yang Huang

Publication Name: Applied Sciences Switzerland

Publication Date: 2021-04-01

Volume: 11

Issue: 7

Page Range: Unknown

Description:

Forklifts are one of the most common types of material handling equipment used in warehouses and distribution centers. Vibration generated by forklifts may have an effect on the performance of unit loads and product damage rates. Historical research projects have focused predominantly on the measurement of vibration for over-the-road transportation. Thus, there is still a lack of understanding of the level of vibration caused by forklifts. The goal of this study was to understand how the vibration that is experienced by unit loads while being transported by forklifts is affected by factors such as speed, road condition, unit load weight, type of forklift, and sensor location. For this study, power spectral density (PSD) measurements were collected using a Lansmont Saver 9X30 data logger. Vibration levels were measured for three different industrial forklifts on two different surface types. The forklifts were driven at two different speeds while carrying two different unit load weights. For all of these conditions, the vibration levels were measured at the forklift carriage, at the back of the fork tine heel, and at the fork tine tips. The results obtained show that the highest vibrational intensity occurred at 3–4 Hz, while the highest overall Grms value observed was 0.145 G2/Hz (between 1–200 Hz). An increase in the forklift speed caused an increase in vibration intensity. In contrast, an increase in the unit load weight carried by the forklift caused a decrease in vibration intensity. Among the three forklifts studied, the gas-powered forklift had the highest vibration intensity, and all forklifts, when driven on asphalt, experienced more vibration.

Open Access: Yes

DOI: 10.3390/app11072901

Circular Economy Aspects of Permanent Magnet Synchronous Reluctance Machine Design for Electric Vehicle Applications: A Review

Mihaly Katona Tamas Orosz

Publication Name: Energies

Publication Date: 2024-03-01

Volume: 17

Issue: 6

Page Range: Unknown

Description:

Innovative technological solutions have become increasingly critical in addressing the transportation sector’s environmental impact. Passenger vehicles present an opportunity to introduce novel drivetrain solutions that can quickly penetrate the electric vehicle market due to their shorter development time and lifetime compared to commercial vehicles. As environmental policy pressure increases and customers demand more sustainable products, shifting from a linear business approach to a circular economy model is in prospect. The new generation of economically competitive machines must be designed with a restorative intention, considering future reuse, refurbishment, remanufacture, and recycling possibilities. This review investigates the market penetration possibilities of permanent magnet-assisted synchronous reluctance machines for mini and small-segment electric vehicles, considering the urban environment and sustainability aspects of the circular economy model. When making changes to the materials used in an electric machine, it is crucial to evaluate their potential impact on efficiency while keeping the environmental impact of those materials in mind. The indirect ecological effect of the vehicle’s use phase may outweigh the reduction in manufacturing and recycling at its end-of-life. Therefore, thoroughly analysing the materials used in the design process is necessary to ensure maximum efficiency while minimising the environmental impact.

Open Access: Yes

DOI: 10.3390/en17061408

Investigation of the performance of direct forecasting strategy using machine learning in State-of-Charge prediction of Li-ion batteries exposed to dynamic loads

Adrienn Dineva Bence Csomós Szabolcs Kocsis Szurke Istvan Vajda

Publication Name: Journal of Energy Storage

Publication Date: 2021-04-01

Volume: 36

Issue: Unknown

Page Range: Unknown

Description:

On account of intense technological advances regarding Electric Vehicles, the state evaluation and prediction issues of Li-ion cells have become increasingly important for ensuring the competitiveness in terms of feasible performance and range. Albeit the wide investigation of various standard modelling and estimation techniques, only limited researches focus on their precision and applicability under heavy transient working conditions. This paper is concerned with Li-ion battery terminal voltage and State-of-Charge (SoC) prediction for two types of dynamic loads. Attention is focused on the investigation of the applicability of direct multi-step forecasting strategy in combination with Machine Learning. Beside that, a feature bank is composed of discharge profiles obtained at different C-rates. The set of discharge curves is proposed to complement the feature extraction, i.e. the additional historical data is considered for model building. Special care is devoted for the design of appropriate training data. Hence, a battery cell model is built for simulating intensive dynamic load scenarios in addition to the experimental setup. The cell model is validated by using measurement data. Results have demonstrated, that in case of WLTP-type discharge load of 0.3C-rate the forecasting performance is highly efficient on measurement data. Under dynamic loads of 1C-rate, or when small historical data is available, the application of feature bank improves the performance. We have obtained comprehensive results proving that the application of direct multi-step forecasting strategy using XGBoost represents a viable alternative to capture real-time the cell dynamics and predict the terminal voltage and SoC of Li-ion batteries exposed to dynamic loads.

Open Access: Yes

DOI: 10.1016/j.est.2021.102351

Exopolysaccharides from lactic acid bacteria: Techno-functional application in the food industry

E. Korcz László Varga

Publication Name: Trends in Food Science and Technology

Publication Date: 2021-04-01

Volume: 110

Issue: Unknown

Page Range: 375-384

Description:

Background: The growing consumer demand for foods that do not contain artificial additives and are “clean labeled” can be addressed in fermented products by using lactic acid bacteria (LAB) capable of synthesizing exopolysaccharides (EPS). There is great variability in LAB-based EPS in terms of quantity, monomer composition, molecular weight, charge, and structure, which results in an array of physicochemical and rheological properties that can be exploited for varied applications in the food industry. Scope and approach: EPS are an alternative class of bio-thickeners widely used in the food industry. This review provides a brief overview of EPS composition and production, and highlights EPS functionality, focusing on specific areas and ways of applying them in food products. Key findings and conclusions: Although EPS-producing LAB strains have been traditionally applied in the manufacture of cultured milks, their use in the production process of low-fat cheeses, different plant-based yogurt alternatives, diverse types of sourdough breads, and reduced-fat fermented meat products are some of the novel applications of these polymers. EPS interact with other food components to improve the rheological and sensory properties of foods and, thus, they can act both as texturizers and stabilizers, increasing the viscosity and mouthfeel of products. Despite the abundance of research findings, a better understanding of the structure–function relationship of EPS in food products still remains a challenge.

Open Access: Yes

DOI: 10.1016/j.tifs.2021.02.014

RFId application in production process of an automotive industry supplier

Petra Döbrössy Dorottya Mánik Lajos Tóth

Publication Name: Ines 2006 10th International Conference on Intelligent Engineering Systems 2006

Publication Date: 2006-12-01

Volume: Unknown

Issue: Unknown

Page Range: 45-48

Description:

The Department of Logistics and Forwarding at Széchenyi István University in Györ, Hungary started a project in an automotive industry supplier company. The purpose of the project is to grow the efficiency of the production process. In order to achieve the target we should reorganized the IT system. During the research we had to take the special production circumstances and the already exist ad hock information system into consideration. The article adumbrates the course of the project shortly, the faults of the system, the own-developed new information system and represents how the human failures could be eliminated though RFId application. © 2006 IEEE.

Open Access: Yes

DOI: DOI not available

Predicting flight arrival times with a multistage model

Gabor Takacs

Publication Name: Proceedings 2014 IEEE International Conference on Big Data IEEE Big Data 2014

Publication Date: 2014-01-01

Volume: Unknown

Issue: Unknown

Page Range: 78-84

Description:

Airlines are constantly looking for ways to cut flight delays, in order to enhance service quality and reduce operational costs. The goal of the data science contest, GE Flight Quest (https://www.gequest.com/c/flight), was to make flights more efficient by improving the accuracy of arrival time estimates. The data set of the contest was 128 GB in size and contained 252 data columns arranged in 34 tables. This paper presents my solution that won third prize under team name Taki. The solution employs a 6-stage model consisting of successive ridge regressions and gradient boosting machines, built on 56 features constructed from the raw data. The hardware environment used for training and running the model was a 64 core machine with 1 terabyte of memory.

Open Access: Yes

DOI: 10.1109/BigData.2014.7004435

AR and ARMA spectral analysis of suspension system of a commercial city bus

Gabor Rodonyi György Istenes Ferenc Szauter

Publication Name: Cinti 2016 17th IEEE International Symposium on Computational Intelligence and Informatics Proceedings

Publication Date: 2017-02-07

Volume: Unknown

Issue: Unknown

Page Range: 151-156

Description:

Concerning the increasing demand for intelligent and efficient urban vehicle systems with low cost maintainability and high passenger comfort, reliable methods are needed to model and to evaluate the imposed performances. The measurements, vibrations emerging on the wheels and the body, that has ben taken on a city bus are analyzed in the frequency domain. In this paper a parametric spectral analysis (AR/ARMA method) of the suspension system of a commercial city bus is presented. The goal of the analysis is to find the right structure for the systems. Parametric methods used in this paper justify and extend the results obtained by non-parametric ones and provide more accurate results for vibration analysis. One of the main conclusions of the investigations is that the quarter-car model structure based on first principles does not reflect the true frequency domain behavior of the system. Thus the identification of the physical model must be complemented with a suitable uncertainty modeling and classification.

Open Access: Yes

DOI: 10.1109/CINTI.2016.7846395

Probabilistic occupancy grid map building for Neobotix MP500 robot

Claudiu Radu Pozna Ernö Horváth

Publication Name: Proceedings of the 2016 13th Workshop on Positioning Navigation and Communication Wpnc 2016

Publication Date: 2017-01-17

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In vehicle and robot navigation low-level tasks such as path planning, obstacle avoidance and autonomous operation are extensively studied nowadays. Most of these task require map building. In this paper a map representation is discussed with the focus for the singular domain of our Neobotix MP500 mobile robot. Among others the state of the art map building techniques will be introduced such as topological map, line map, landmark-based map and of course in more detail the occupancy grid based map. The probabilistic representation of the occupancy grid will be examined as a map building problem for the given mobile robot.

Open Access: Yes

DOI: 10.1109/WPNC.2016.7822843