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ROBOVOLC is a new robotic system that has been designed to help scientists in the exploration of volcanoes. It is composed of three subsystems: a rover platform with six articulated and independently actuated wheels; a manipulator arm to collect rock samples, drop and pick up sensors and sample gas; and a pan‐tilt turret with a high resolution camera, video‐camera, infrared camera and a doppler radar for gas speed measurement. This paper contains a short description of the system, following an introduction to the problem and review of the state‐of‐the‐art. Finally, results from the first test campaign on Mount Etna during September 2002 are briefly described.

The assessment of the quality of the electric power supply, as well as that of the electric loads, is becoming a critical problem, especially when the liberalization of the electricity market is involved. Power quality can be evaluated by means of a number of quantities and indices whose measurement is not straightforward and is generally attained by means of digital signal processing techniques based on complex algorithms. The assessment of the uncertainty of the results of such measurements is a critical, open problem. This paper proposes a general purpose approach, based on the Monte Carlo method that, starting from the estimated contributions to the uncertainty of each device in the measurement chain, estimates the probability density distribution of the measurement result, and therefore, its standard uncertainty. This approach has been experimentally validated for the active power measurement and applied to the estimation of the uncertainty of the measurement of more complex power quality indices.

Petroleum hydrocarbons are naturally occurring flammable fossil fuels used as conventional energy sources. It has carcinogenic, mutagenic properties and is considered a hazardous pollutant. Soil contaminated with petroleum hydrocarbons adversely affects the properties of soil. This paper aim to remove pollutants from the environment is an urgent need of the hour to maintain the proper functioning of soil ecosystems.

The ability of micro-organisms to degrade petroleum hydrocarbons makes it possible to use these microorganisms to clean the environment from petroleum pollution. For preparing this review, research papers and review articles related to petroleum hydrocarbons degradation by micro-organisms were collected from journals and various search engines.

Various physical and chemical methods are used for remediation of petroleum hydrocarbons contaminants. However, these methods have several disadvantages. This paper will discuss a novel understanding of petroleum hydrocarbons degradation and how micro-organisms help in petroleum-contaminated soil restoration. Bioremediation is recognized as the most environment-friendly technique for remediation. The research studies demonstrated that bacterial consortium have high biodegradation rate of petroleum hydrocarbons ranging from 83% to 89%.

Proper management of petroleum hydrocarbons pollutants from the environment is necessary because of their toxicity effects on human and environmental health.

This paper discussed novel mechanisms adopted by bacteria for biodegradation of petroleum hydrocarbons, aerobic and anaerobic biodegradation pathways, genes and enzymes involved in petroleum hydrocarbons biodegradation.

The purpose of this paper is to use the Twitter Search Network of the Apache NodeXL data discovery tool to extract over 5,000 data from Twitter accounts that twitted, re-twitted or commented on the hashtag, #NigeriaDecides, to gain insight into the impact of the social media on the politics and administration of developing countries.

Several algorithms like the Fruchterman-Reingold algorithm, Harel-Koren Fast Multiscale algorithm and the Clauset-Newman-Moore algorithms are used to analyse the social media metrics like betweenness, closeness centralities, etc., and visualize the sociograms.

Results from a typical application of this tool, on the Nigeria general election of 2015, show the social media as the major influencer and the contribution of the social media data analytics in predicting trends that may influence developing economies.

With this type of work, stakeholders can make informed decisions based on predictions that can yield high degree of accuracy as this case. It is also important to stress that this work can be reproduced for any other part of the world, as it is not limited to developing countries or Nigeria in particular or it is limited to the field of politics.

Increasingly, during the 2015 general election, citizens have taken over the blogosphere by writing, commenting and reporting about different issues from politics, society, human rights, disasters, contestants, attacks and other community-related issues. One of such instances is the #NigeriaDecides network on Twitter. The effect of these showed in the opinion polls organized by the various interest groups and media houses which were all in favour of GMB.

The case study the authors took on the Nigeria’s general election of 2015 further strengthens the fact that the developing countries have joined the social media race. The major contributions of this work are that policy makers, politicians, business managers, etc. can use the methods shown in this work to harness and gain insights from Big Data, like the social media data.

Dynamics of population mutagenesis during 22 consecutive generations of animals, as well as genetic radioadaptation were studied in natural populations of small mammals (bank voles) under chronic low‐intensive irradiation due to the Chernobyl accident. The data obtained point to oppositely directed processes in irradiated populations: accumulation of mutations (genetic load of populations) and formation of genetic radioadaptation. It is suggested that the frequencies of genetic damages in populations could be higher in the absence of radioadaptation process. A relationship between the frequencies of cytogenetic injuries and low doses of radiation was revealed in animal generations studied. The non‐linear dose‐effect curves are most likely to be defined by the complicated microevolutionary processes in populations. The results obtained indicate the absence of genetic effect threshold of low dose radiation. Besides, they show that a dependence of cytogenetic effects on radiation low doses in series of irradiated generations cannot be revealed using linear equations.

The aim of the paper is the formulation of a simple hysteresis model entirely based on generally accepted concepts.

According to this, the modelling of loops has been achieved by the application of the Langevin‐Weiss law of magnetization to transformer equivalent circuits. The loops are generated by the change of the phase of current, introduced by the resistance modelling iron loss. Differential circuit equations have been solved with the help of standard Mathcad procedures.

In spite of the simplicity of such approach, the accuracy of hysteresis loops and iron loss approximations is better than in PSpice simulations and the model can be easily extended to dynamic loops.

The application of the model is limited to lower frequencies, where the rise of frequency leads to the widening of the loops without the radical change of their shapes.

Presented approach may be useful in simplified analysis of low frequency transformer circuits and in the primary explanation of hysteresis phenomena for teaching purposes.

Contrary to other models based on saturation curves, the dynamic hysteresis loops presented in this paper are obtained with the use of basic laws and concepts, without the introduction of any additional assumptions and the separate treatment of the lower and upper branches of the loops.

The main idea is the comparison between composites including natural fibres (such as the linoleum fibres) and typical composites including carbon fibres or glass fibres. The comparison is proposed for different structures (plates, cylinders, cylindrical and spherical shells), lamination sequences (cross-ply laminates and sandwiches with composite skins) and thickness ratios. The purpose of this paper is to understand if linoleum fibres could be useful for some specific aerospace applications.

A general exact three-dimensional shell model is used for the static analysis of the proposed structures to obtain displacements and stresses through the thickness. The shell model is based on a layer-wise approach and the differential equations of equilibrium are solved by means of the exponential matrix method.

In qualitative terms, composites including linoleum fibres have a mechanical behaviour similar to composites including glass or carbon fibres. In terms of stress and displacement values, composites including linoleum fibres can be used in aerospace applications with limited loads. They are comparable with composites including glass fibres. In general, they are not competitive with respect to composites including carbon fibres. Such conclusions have been verified for different structure geometries, lamination sequences and thickness ratios.

The proposed general exact 3D shell model allows the analysis of different geometries (plates and shells), materials and laminations in a unified manner using the differential equilibrium equations written in general orthogonal curvilinear coordinates. These equations written for spherical shells degenerate in those for cylinders, cylindrical shell panels and plates by means of opportune considerations about the radii of curvature. The proposed shell model allows an exhaustive comparison between different laminated and sandwich composite structures considering the typical zigzag form of displacements and the correct imposition of compatibility conditions for displacements and equilibrium conditions for transverse stresses.

The purpose of this paper is to investigate if differences exist between the four wine-consuming generations in wine purchasing behavior, the desirability of wine attributes when making a purchase decision and information sources used. It examines if generational market segmentation is an actionable and valuable strategy for the wine industry. Generation Z, Millennials, Generation X and Baby-Boomers are the four generations examined. This research also investigates if the generations behaved differently concerning wine consumption during the COVID-19 pandemic. Further, expectations concerning future wine purchasing behavior are examined.

An online survey was conducted between April 29, 2020 and May 7, 2020, with a sample size of 944 consumers from Western US States (California, Washington, Idaho, Oregon and Nevada). One-way analysis of variance technique and Chi-square tests were used to examine differences.

Segmentation by generation is appropriate when creating products, pricing, determining channels of distribution and creating messaging for a specific wine brand. The COVID-19 pandemic caused channel shifting that is expected to continue after the pandemic.

This is the second academic paper that examines differences in wine purchasing behavior between generations including Generation Z and the only study that examines the purchasing behavior changes and expectations for the future by generation concerning the COVID-19 pandemic.

A national survey should be conducted to confirm that the results from the sample that was mostly from California and neighboring states reflect the national wine consumer in the USA.

The research identifies the products, prices, channels of distribution and messaging that are appropriate to target each generation.

The purpose of this paper is to propose a comparative study between different structures composed of fiber-reinforced composite materials. Plates, cylinders and cylindrical and spherical shell panels in symmetric 0°/90°/0° and antisymmetric 0°/90°/0°/90° configurations are analyzed considering carbon fiber, glass fiber and linoleum fiber reinforcements.

A free vibration analysis is proposed for different materials, lamination sequences, vibration modes, half-wave numbers and thickness ratios. Such an analysis is conducted by means of an exact three-dimensional shell model which is valid for simply supported structures and cross-ply laminations. The employed model is based on a layer-wise approach and on three-dimensional shell equilibrium equations written in general orthogonal curvilinear coordinates.

The proposed study confirms the well-known superiority of the carbon fiber-reinforced composites. Linoleum fiber-reinforced composites prove to be comparable to glass fiber-reinforced composites in the case of free vibration analysis. Therefore, similar frequencies are obtained for all the geometries, thickness ratios, laminations sequences, vibration modes and a large spectrum of half-wave numbers. This partial conclusion needs further confirmations via static, buckling and fatigue analyses.

An exact three-dimensional shell model has been used to compare several geometries embedding carbon fiber composites and natural fiber composites.