Search in Publications

Found 6327 publications

Effect of protein content on the thermal effusivity of foods

G. Szafner Nóra Gombköto Ottó Dóka

Publication Name: Acta Alimentaria

Publication Date: 2021-12-31

Volume: 50

Issue: 4

Page Range: 475-483

Description:

The availability of thermophysical properties of both foods and their constituents is of considerable importance to the industry. The thermal effusivity is one of the less explored thermophysical parameters. It governs the penetration of heat into materials and is defined as the square root of the product of thermal conductivity of the material, volume-specific heat capacity, and density. This paper describes the application of a relatively new inverse photopyroelectric method (IPPE) to determine thermal effusivity of dehydrated whey protein isolate and egg white powder versus protein content. In both cases the effusivity values decreased linearly with increasing protein content. One percent increase in protein content of whey protein isolate and egg white lead to 6.5 and 7.2 Ws1/2 m-2 K-1 decrease in effusivity values, respectively.

Open Access: Yes

DOI: 10.1556/066.2021.00042

Sight distance analyses for autonomous vehicles in Civil 3D

Dániel Miletics Khalil Khaska

Publication Name: Pollack Periodica

Publication Date: 2021-12-31

Volume: 16

Issue: 3

Page Range: 33-38

Description:

Nowadays, self-driving cars have a wide reputation among people that is constantly increasing, many manufacturers are developing their own autonomous vehicles. These vehicles are equipped with various sensors that are placed at several points in the car. These sensors provide information to control the vehicle (partially or completely, depending on the automation level). Sight distances on roads are defined according to various traffic situations (stopping, overtaking, crossing, etc.). Safety reasons require these sight distances, which are calculated from human factors (e.g., reaction time), vehicle characteristics (e.g., eye position, brakes), road surface properties, and other factors. Autodesk Civil 3D is a widely used tool in the field of road design, the software however was developed based on the characteristics of the human drivers and conventional vehicles.

Open Access: Yes

DOI: 10.1556/606.2021.00380

The Role of food aid and livelihood interventions in mediating the relationship between household’s resilience and economic empowerment

Laszlo Vasa Nassar Samia Zsuzsanna Naárné Tóth

Publication Name: Economic Annals Xxi

Publication Date: 2021-12-27

Volume: 194

Issue: 11-12

Page Range: 151-163

Description:

Theconceptofresiliencehasbeenutilizedtoexaminemorecomplexecologicalandsocioeconomic systems such as agri-food systems in developing countries. Gaza has one of the high unemployment rates globally, therefore keeping people imprisoned in poverty and dependent on external support to existing. The strategy for poverty reduction in Gaza primarily consists of giving food aid or multi-purpose cash-based assistance and livelihood projects; nevertheless, this does not reduce unemployment or poverty in the long term. Non-Governmental Organizations (NGOs) have increased their efforts to provide more effective and comprehensive interventions to the affected populations, especially in the Gaza Strip. The research implemented a quantitative methodology distributed to over 300 household benefited from food aid and livelihood interventions through the NGOs in Gaza Strip. The questionnaire had been constructed based on the Likert Scale ranging from 1 (Strongly Agree) to 5 (Strongly Disagree). The data had been treated using SPSS statistical tool and AMOS for structural equation modeling and analysis to study the mediating effect of food aid and livelihood interventions on the relationship between household resilience and economic empowerment in the Gaza Strip. The research found that the resilience ability of many families in the Gaza Strip has increased because of the humanitarian assistance provided by NGOs, which lead to reducing poverty and household resilience plays a vital role in minimizing poverty and alleviating suffering through empowering and engaging them in the economy. The research also found that food aid tends to critically impact the relationship between household resilience and economic empowerment. NGOs play an essential role in engaging the poor in the economy through providing food security and encouraging new investments and efforts to improve help effectiveness via greater coordination among players involved in the implementation and better planning, targeting, and providing aid to people in Gaza Strip. The research findings also showed that livelihood interventions mediate the relationship between household resilience and economic empowerment in Gaza Strip. The structural model supports that the livelihood interventions modulated the association between household resilience and economic empowerment.

Open Access: Yes

DOI: 10.21003/ea-v194-19

Rapid fleet condition analysis through correlating basic vehicle tracking data with engine oil ft-ir spectra

Charlotte Besser Péter Raffai András Lajos Nagy Bettina Ronai Adam Agocs J. Rohde-Brandenburger Nicole Dörr

Publication Name: Lubricants

Publication Date: 2021-12-01

Volume: 9

Issue: 12

Page Range: Unknown

Description:

Engine oil condition and tribological performance are strongly interrelated. Accordingly, oil condition monitoring is common in various applications. This is especially important, as oil condition depends on the fueling and utilization profile of an internal combustion engine. Common practice involves the measurement of various parameters, such as the total acid number and total base number, oxidation, nitration, viscosity, and elemental composition; thus, it can be time-consuming and resource-intensive. This study provides a methodology for rapid analysis for large vehicle fleets or sample sizes, using only Fourier-transformed infrared spectroscopy and the subsequent multivariate data analysis offers a rapid alternative to commonly available methods. The described method provides a rapid, cost-efficient, and intuitive approach to uncovering differences in the oil condition. Furthermore, understanding the underlying reasons in engine construction and the resulting chemical degradation is also possible.

Open Access: Yes

DOI: 10.3390/lubricants9120114

Humanitarian Drones: A Review and Research Agenda

Horst Treiblmaier Abderahman Rejeb Karim Rejeb Steve Simske

Publication Name: Internet of Things Netherlands

Publication Date: 2021-12-01

Volume: 16

Issue: Unknown

Page Range: Unknown

Description:

This study investigates the capabilities, performance outcomes, and barriers of drones applied to humanitarian logistics (HL). A systematic literature review was conducted to synthesize prior research on drones and cumulatively identify current knowledge gaps which require further investigation. In order to identify the relevant literature on the topic, a rigorous research protocol was applied for the retrieval and selection processes. In total, 142 publications fulfilled the selection criteria and were thoroughly analyzed. The findings of this review paper summarize the capabilities, barriers and performance outcomes of humanitarian drones applied to logistics operations, management, and governance in a comprehensive framework. More specifically, three important capabilities (i.e., transportation and delivery; surveying and monitoring; communication and integration), three performance outcomes (i.e., flexibility and responsiveness; cost reduction; sustainability) and adoption barriers in three areas (i.e., technology; organization; environment) were identified. Based on these findings, future research directions are derived for the capabilities of humanitarian drones, their performance outcomes, and their respective barriers. This study analyzes potential applications of drones in the humanitarian field and presents a comprehensive agenda that structures and guides further research on the topic.

Open Access: Yes

DOI: 10.1016/j.iot.2021.100434

Development of New HS–SPME–GC–MS Technique to the Measurement of Volatile Terpenoid Profile of Milk

E. Lakatos Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Food Analytical Methods

Publication Date: 2021-12-01

Volume: 14

Issue: 12

Page Range: 2585-2596

Description:

This study presented the development of such a HS–SPME–GC–MS technique, with the use of which, directly from the raw milk sample matrix, both qualitatively and quantitatively; the volatile terpenoids (α-pinene, sabinene, β-pinene, p-cymene, limonene, linalool, α-thujene, camphor, menthol, methyl chavicol, caryophyllene E, α-humulene) can be determined, derived from herbs eaten by the dairy animals by different feeding methods. Repeatability was less than 10% in the case of milk fat samples. The estimated limits of quantitation were between 2 and 16 ng/g. The lowest values were 2 ng/g for p-cymene and methyl chavicol; the highest value was 16 ng/g for caryophyllene. In the case of goat milk, the repeatability was better than 8% except for α-thujene. The estimated limits of quantitation were between 1 and 8 ng/g. The lowest values were 1 ng/g for β-pinene, p-cymene and limonene, and the highest value was 8 ng/g for linalool. In milk fat, the highest concentration was identified in caryophyllene E (470 ng/g) and α-humulene (430 ng/g), while the lowest concentration was in p-cymene (2 ng/g) and camphor (2 ng/g). In goat milk, limonene was present in all samples, but its amount varied depending on the type of consumed herb. Methyl chavicol and caryophyllene E were detected in goat’s milk only in one case. The former was detected in sage milk at 2.09 ng/g and the latter in tarragon milk at 2.28 ng/g. We have also successfully demonstrated that the feed consumed by dairy animals also affects the quality of dairy products.

Open Access: Yes

DOI: 10.1007/s12161-021-02070-9

Addressing storage time restrictions in the S-graph scheduling framework

Máté Hegyháti Olivér Osz Tibor Holczinger

Publication Name: Optimization and Engineering

Publication Date: 2021-12-01

Volume: 22

Issue: 4

Page Range: 2679-2706

Description:

Storage planning and utilization are among the most important considerations of practical batch process scheduling. Modeling the available storage options appropriately can be crucial in order to find practically applicable solutions with the best objective value. In general, there are two main limitations on storage: capacity and time. This paper focuses on the latter and investigates different techniques to tackle limited storage time within the S-graph framework. The S-graph framework is a collection of combinatorial algorithms and a directed graph based model that has been introduced three decades ago and has been under development ever since. In this work, several options for addressing storage time limitations within the framework were implemented and tested for efficiency. The empirical results over a huge number of tests have unequivocally favored one of the approaches, which will be applied in later developments.

Open Access: Yes

DOI: 10.1007/s11081-020-09548-1

Physical activity and screen time among hungarian high school students during the COVID-19 pandemic caused distance education period

Ferenc Ihász Robert Podstawski Johanna Takács Imre Soós Tamás Gyömörei Zsolt Bálint Katona László Kerner Zoltán Alföldi

Publication Name: International Journal of Environmental Research and Public Health

Publication Date: 2021-12-01

Volume: 18

Issue: 24

Page Range: Unknown

Description:

Background: High school education took place in the form of distance learning during SARS-CoV-2 pandemic worldwide, including Hungary. Decreased physical activity and an increase in inactive behaviours may lead to an increased risk of obesity, diabetes, and cardiovascular disease. Aim: Our study targeted changes in physical activity (aerobic exercise, muscle strengthening) and screen time in adolescents and young adults during the pandemic. Methods: High school students were interviewed in 66 public schools in 37 Hungarian cities (N = 2508). Survey items on physical activity and screen time were derived from the WHO Health Behaviour of School-aged Children Survey and the Centers for Disease Control Youth Risk Behavior Survey. A 2 × 2 factorial ANCOVA was used to test the effects of gender (male vs. female) and/or age (adolescents vs. young adults) on the reported changes in physical activity and screen time before and during lockdown (covariate: BMI Z-score). Results: The majority of the cohort indicated less physical activity. Aerobic and muscle-strengthening type of exercises significantly decreased, and screen time increased during distance education. Male individuals showed a higher decrease in the level of aerobic exercise, and young adults reported a higher increase in the time spent in front of the screen.

Open Access: Yes

DOI: 10.3390/ijerph182413024

Elasto-Plastic limit analysis of reliability based geometrically nonlinear bi-directional evolutionary topology optimization

János Lógó Majid Movahedi Rad Muayad Habashneh

Publication Name: Structures

Publication Date: 2021-12-01

Volume: 34

Issue: Unknown

Page Range: 1720-1733

Description:

This paper presents elasto-plastic limit analysis of reliability-based geometrically nonlinear topology optimization. For this purpose, by reason of uncertainties the volume fraction is considered randomly during optimization. Thus reliability-based design has been considered for solving the problems. To perform reliability-based topology optimization design, the Monte-Carlo simulation method has been applied to calculate the probability of failure, thus the reliability index. Besides, bi-directional evolutionary structural optimization (BESO) method is used to consider the effect of geometrically nonlinear design for elasto-plastic analysis. Plastic behavior is controlled by applying a bound on the plastic limit load multipliers using limit analysis. The adequacy of the proposed method is exhibited by three 2D benchmark problems. 2D models of L-shape beam and U-shaped plate are considered for reliability-based design and geometrically nonlinear analysis topology optimization in case of elastic material. Additionally, 2D and 3D elasto-plastic material models have been considered to demonstrate that the proposed method can find the optimal topology of elasto-plastic models for reliability-based design and geometrically nonlinear analysis.

Open Access: Yes

DOI: 10.1016/j.istruc.2021.08.105