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Additive manufacturing techniques continue to develop and cover all industrial fields. However, the performances of aspect and mechanical behavior of the parts obtained by this process remain to be mastered and are still the subject of current research works. Among these performances, the one corresponding to the resistance to the propagation of cracks. In order to improve this very interesting property in various industrial fields, it is desirable to master the understanding of crack propagation in this type of structure obtained by 3D printing. The objective of this paper is to analyze and understand the effect of the adopted raster angle on the crack propagation in SENT specimens obtained by FDM in ABS (Acrylonitrile-Butadiene-Styrene). Two approaches were developed: one is experimental to determine the critical stress intensity factor KIC and the other is numerical to predict the possible paths of crack propagation.

This study aims to assess the delamination effect and predict the evolution of damage in 3D printed specimens to investigate the mechanical behavior occurring due to the delamination of the layers of 3D printed thermoplastic polymers. Thus, additively manufactured ABS samples are subjected to tensile tests Made for different thicknesses of specimens by subtracting layer by layer. The mechanical behavior of the layers and the adherence between the layers are studied in this paper. The deposition of the layers is modeled as a laminated material. The delamination effect on the resistance of printed material is evaluated experimentally by comparing the mechanical characteristics of homogenously printed specimens, and laminated layers gathered together. Thus, the global resistance is reduced significantly due to the lack of adherence. Besides, crack growth, and critical intensity factor investigation are based on damage and rupture mechanics theories. Furthermore, the results allowed us to evaluate the energy behavior of the 3D printed material subjected to static loads and subsequently predict the evolution of the damage and find out the impact of layers' delamination. Indeed, we determined three stages of damage along with the critical life fraction leading to the failure of the specimen.

In view of the increasing amount of plastic waste due to a yearly rise in production volume, mechanical recycling of post-industrial waste offers a way to use the scarce resources on earth more efficiently in addition to reducing the global warming potential in the production of raw materials. Therefore, this study addresses the calculation of the product carbon footprint for sorted industrial waste according to the specifications of ISO 14067. The plastics acrylonitrile–butadiene–styrene copolymer (ABS), polyamide 6.6 with 30% glass fiber (PA66GF30), polycarbonate (PC) and polyoxymethylene (POM) were balanced in Umberto LCA+ using the Ecoinvent v3.8 and GaBi SP40 2020 databases and primary data collection from the recycling company Occhipinti. A cut-off approach was applied as an allocation method for evaluating the industrial waste so that the plastic for grinding was imported without burdens from the previous product system. The results show that for all plastics under study, one of the main drivers of the carbon footprint is plastic dust from the grinding process. This insight was used in sensitivity analyses to optimize the modelled processes for a more sustainable production. Improvement potentials were identified by using solar power and disposing of the plastic dust separately according to the type of plastic.

The use of components obtained through the additive manufacturing (AM) technique has become increasingly widespread in recent years, playing a central role in industrial production, and in particular in some fields such as automotive, biomedical, aerospace and electronics. Among all AM techniques, FDM (Fused Deposition Modelling) represents the most used printing technique to produce polymeric and composite components, thanks to the flexible printing process, the low cost and the diversity of the materials adopted. The aim of the present work concerns the comparison between the mechanical properties of three plastic materials printed with the FDM technique (polylactic acid PLA, polyethylene terephthalate glycol-modified PETG and Acrylonitrile-butadiene-styrene ABS) using an Original Prusa i3 MK3S, by varying the raster angle between 0°, 45° and 90° degrees. Infrared Thermography has been adopted to monitor the temperature evolution during static tensile tests and to assess stress level that can initiate damage within the material. Failure analysis was performed to correlate the mechanical behaviour with the microstructural characteristics of the materials.

Background: Low back pain is a very common health problem amongst population and a major cause of disability that affects work performances and well-being. It is can be acute, sub-acute or chronic. It is affects all ages of the population and is the most common reason for medical consultations. The main aims of study:To assessment the level of nurses` knowledge of lower back pain exercises, to identify the difference between nurse`s knowledge level in lower back pain exercise according to demography variables and knowing the percentage of nurses who pass and not pass regarding lower back pain and it`s exercises. Methodology: This study included a sample of (60) nurses, (26) males and (34) females, this study was conducted on the nursing staff in various hospitals. The questionnaire was used to collect the required information and it is composed of (24) questions about lower back pain and it`s exercises in different cases, regarding the score (I strong agree=2, I agree=1, I don't agree=0) where total scores=48 and also include variables (level of education, and years of experiences). And use the statistical program (spss) to analyze the results. The data were analyzed using the Statistical Package for Social Sciences (SPSS), version 26. Conclusions · More than half of the sample they got (16 to 31) score was having medium level of knowledge. · Sample study got (83 %) pass regarding information of lower back pain domain and sample study got (72 %) pass regarding exercise domain of lower back pain. Recommendations · Add physiotherapy in the curricula of health institutes and colleges of nursing. Give training courses for nurses who working at hospital in another unites about how deal with lower back pain and it`s exercises&nbsp

The access to molecular collections worldwide greatly improves the quality of scientific research by making a growing number of data available for investigation. The efforts on digitization also aim at facilitating the exchange of material between institutions and researchers that must follow regulations in place and respect best practice. The handbook presented here proposes a workflow to follow to safely exchange materials, in accordance with international laws and legislations. We make numerous recommendations here to help the institutions and researchers to navigate the legal and administrative procedures, to manage molecular collections in the best way possible.

Acrylonitrile-butadiene-styrene test specimens were additively manufactured by fused deposition method to investigate the effects of infill pattern and density on wear rate, coefficient of friction, wear mechanisms, and microscopic wear characterization. The surface morphology of specimens was characterized using a scanning electron microscope. Under constant parameters of applied load, sliding speed, and sliding time, wear tests were carried out at room temperature. The study revealed that a grid pattern of high infill density and a honeycomb pattern of low infill density showed the lowest wear rate and lowest coefficient of friction compared to the rectilinear pattern. Infill pattern and density affected the wear rate behavior of specimens directly. Moreover, adhesion between additively manufactured layers along with surface texture affects the wear behavior and wear rate. Increasing infill density allowed poor cooling of previously built layers. Longer process time results in rough surfaces.

Mattel’s Barbie dolls are the most famous and iconic dolls since 1959. Today, they are being collected by individuals and often conserved in museum environments due to their cultural and historical significance reflecting everyday life and historical events. However, just like most museum objects made of plastics, both historical and more recent Barbies show evident degradation phenomena. Firstly, Barbies were made of plasticized polyvinyl chloride (PVC), affected by the migration of additives—mostly the plasticizers—from the bulk phase to the outermost layer, appearing as a tacky and glossy exudate. Over the years, Barbies’ polymeric constituents were replaced with more stable ones, whose additives migration is limited compared to PVC, even though still occurring. Multispectral photography in visible (VIS) and ultraviolet (UV) light, microscopical observations in VIS and UV light, and Fourier Transform Infrared spectroscopy in the Attenuated Total Reflectance mode (FT-IR ATR) were performed to characterize the constituent materials of 15 Barbies produced between 1959 and 1976, bridging the information gap on their processing over the years. The micro-invasive multi-analytical approach also allowed for the characterization of the degradation products, permitting the reference of the exudated compound to the specific bulk polymer.

In this work, aqueous biphasic systems (ABSs) formed by copolymers, ionic liquids (ILs) and natural deep eutectic solvents (NADES) have been demonstrated to be effective separation platforms for the extraction of hydrophobic pharmaceutical ingredients such as parthenolide (PAR). This work addresses the determination of the liquid–liquid equilibrium of ABS composed of choline lactate IL or choline chloride – lactic acid NADES and two different block copolymers Pluronic (PL17R4 and PL10R5), and their influence on the ABS formation and extraction efficiency of PAR. The ability of Pluronics to form ABS is compared to widely used polypropylene glycol polymer (PPG400). Comparing the effect of the ionic liquid and NADES on the ABS formation, it is shown that both salting-our reagents successfully form ABS and do not affect the extraction efficiency of PAR. The main influence on the high parthenolide extraction efficiency (>96%) is governed by the hydrophobic interactions between Pluronic and investigated compound, regardless on the applied salting-out reagent. Due to a high extraction efficiency achieved in PL-rich phase and promissing medical features of PAR, obtained results showed that this phase could be used as biocompatible drug delivery system. Avoiding commercially available organic solvents, elevated temperatures and pressure, the proposed method is greener alternative for PAR extraction.

Fused Deposition Modeling (FDM), is one of the most popular and widely used Additive Manufacturing filament based technology employing materials such as Acrylonitrile Butadiene Styrene (ABS), Polycarbonate (PC), Thermoplastic Polyurethane (TPU) and Polylactic Acid (PLA). In this technique, the part is built up layer-by-layer, affecting, both the resolution along the z-axis, and the mechanical properties dependent on the mesostructure, controlled by a large amount of production parameters such as layer thickness, raster orientation, number of contour and air gap. When dealing with functional and structural printed parts, a deep understanding of these tunable building parameters and their influence on the mechanical properties is of the utmost importance and over the years many experimental studies have been carried to investigate this need. This study is intended to explore specimens realized through FDM technique with different combinations of printing parameters to analyse their effect on the mechanical properties of ABS Plus p430. To this aim, tensile and compression specimens, had been designed and tested. Sixteen different types of tensile specimen had been realized by varying four different parameters, namely, layer thickness, part interior style, infill orientation and number of contours. Whereas, the number of compression specimens had been limited to four considering the variation of two parameters: layer thickness and part interior style. Three samples for each specimen had been produced in ABS Plus p430 using a Stratasys Fortus 250mc FDM printer and tested with a universal testing machine through tension and compression tests to analyse the correlation between printing parameters and material properties. Test results had led to important conclusions on the consistency and homogeneity of the mechanical properties and on the variation of the material’s performances in accordance with the different combinations of production parameters.

The objective of the present work is to evaluate the influence of material color on mechanical properties of fused deposition modeling (FDM) parts. The performance of the products is evaluated by testing eight different colors of acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) material in terms of tensile strength, compressive strength, and flexural strength. The analysis of data shows a significant difference in mechanical characteristics of prints depending on filament color. For different colors, these three strengths almost follow the same rising and falling tendency. In order to explore the relationship between mechanical strengths and filament colors, the color-mixing theory and the least-squares method are adopted to fit the best ratio coefficients of different color combinations. Results are presented showing that the strength value (e.g., tensile) of the mixed color can be evaluated through that of primary colors by fitting the other strength (e.g., compressive or flexural). It is shown that the predicted value is always no more than 7% error compared with the actual strength, in spite of two-color or three-color mixtures. An additional confirmation test with seven colored PLA filaments from different suppliers was conducted to focus on the extensibility. The outcomes show the maximum fitting errors of strengths for mixed colors in all cases are within 5%, proving the effectiveness and applicability of this predicted approach. This study can bring a detailed analysis that enables better estimation of the function of material color and contributes to improving the property of FDM printed products for consumers by choosing the suitable filament color.

Ferromagnetic materials, such as ferrites, are employed for magnetically tuned radio frequency (RF) circuits. Ferrites exhibit both electric permittivity and magnetic permeability and independent RF characterization of these two properties is crucial for accurate design and modeling of RF circuits. A method that independently extracts each property over Wi-Fi frequencies is presented here, where complex permittivity and permeability of ferrite nano-particles are extracted using resonance frequency sensitivity of a 3D printed metallic cavity to various samples under test and their placement in the cavity. Air-filled 3D printed rectangular cavity using acrylonitrile butadiene styrene (ABS) are shielded using copper sheets; the structure of air-filled cavity is designed to excite TE101z as the dominant resonance mode that resonates at 2.4 GHz. A cylindrical shape material under test (MUT) was added to the cavity at different positions for high electric and magnetic fields, while the resonant frequency change and degradation in quality factor of the resonant cavity are employed for accurate independent extraction of electric permittivity and magnetic permeability of MUT. The sample was prepared with volumetric distribution of 60:40 nanoparticles to glue ratio. In particular, a 3D printed composite sample of ABS with NiFe2O4 magnetic nanoparticles is placed in positions of high electric or high magnetic energy densities of the metallic cavity, while any changes in resonant frequency and its frequency selectivity are observed from the cavity insertion loss characteristics. Both perturbation theory (as analytical) and finite element method (as numerical) techniques are employed for extraction of complex permittivity and permeability of NiFe2O4. The perturbation theory provides accurate extraction, which is also numerically confirmed using curve fitting of the full wave simulated scattering parameters to the measured results.

The effect of short carbon fiber (SCF) filler on the mechanical properties of 3D-printed acrylonitrile butadiene styrene (ABS) was investigated. The fused filament fabrication (FFF) method was used for the manufacturing of samples. Elastic properties and strength characteristics of samples made of conventional ABS and SCF-reinforced ABS were compared in tensile and bending tests. Fracture toughness and critical strain energy release rate were also determined. In addition, 3D-printed monofilament SCF-reinforced samples were fabricated, the internal structure of which was analyzed using microcomputed tomography (micro-CT). Based on the tomography data, finite-element (FE) models of representative volume elements (RVEs) of the reinforced material were created and used for the numerical calculation of effective characteristics. Numerical and experimental results for the effective elastic properties were compared with the Mori-Tanaka homogenization technique. The ABS samples filled with SCF showed considerably higher mechanical characteristics than those of the conventional ABS. Finally, the dependence between the strength characteristics and elastic properties of the samples on the diameter of the nozzle used for 3D printing was established. 3D-printed ABS reinforced with SCF demonstrated a gain in tensile strength and fracture toughness by 30% and 20%, respectively. Interlayer adhesion strength in flexure tests showed an increase of 28% compared to pure ABS samples.

Additive manufacturing (AM) also called 3D printing, is an emerging process in the manufacturing sector with increasing new applications in aerospace, prototyping, medical devices and product development, among others. The resistance of the AM part is determined by the chosen material and the printing parameters. As novel materials and AM methods are continuously being developed, there is a need for the development and mechanical characterization of suitable materials for 3D printing. In this study, the influence of the material and the 3D-printing parameters on the mechanical properties of additive manufactured thermoplastic parts was investigated. Three different filaments that are commercially available: Polylactic acid (PLA), acrylonitrile butadiene styrene (ABS) and Tritan were used. Tensile and flexural tests were carried out, in accordance to ASTM standards, to investigate and compare the mechanical properties of the AM parts as a function of material used. The results showed that the type of filaments had the greatest influence on the mechanical properties of the AM parts. The maximum strength and stiffness were obtained for the PLA specimens. Tritan displayed the highest deformation, while the PLA manifested the lowest deformation capacity. The mechanical properties of the printed parts also depend on the printing parameters. The parameters used in this work are a good compromise between the printing time and the mechanical properties.

Fused Deposition Modeling (FDM) is capable of producing complicated geometries and a variety of thermoplastic or composite products. Thus, it is critical to carry out the relationship between the process parameters, the finished part’s quality, and the part’s mechanical performance. In this study, the optimum printing parameters of FDM using oil palm fiber reinforced thermoplastic composites were investigated. The layer thickness, orientation, infill density, and printing speed were selected as optimization parameters. The mechanical properties of printed specimens were examined using tensile and flexural tests. The experiments were designed using a Taguchi experimental design using a L9 orthogonal array with four factors, and three levels. Analysis of variance (ANOVA) was used to determine the significant parameter or factor that influences the responses, including tensile strength, Young’s modulus, and flexural strength. The fractured surface of printed parts was investigate using scanning electron microscopy (SEM). The results show the tensile strength of the printed specimens ranged from 0.95 to 35.38 MPa, the Young’s modulus from 0.11 to 1.88 GPa, and the flexural strength from 2.50 to 31.98 MPa. In addition, build orientation had the largest influence on tensile strength, Young’s modulus, and flexural strength. The optimum printing parameter for FDM using oil palm fiber composite was 0.4 mm layer thickness, flat (0 degree) of orientation, 50% infill density, and 10 mm/s printing speed. The results of SEM images demonstrate that the number of voids seems to be much bigger when the layer thickness is increased, and the flat orientation has a considerable influence on the bead structure becoming tougher. In a nutshell, these findings will be a valuable 3D printing dataset for other researchers who utilize this material.

Made available in DSpace on 2020-12-12T02:21:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Purpose: The purpose of this paper is to investigate and discuss the influence of printing parameters on the mechanical properties of acrylonitrile butadiene styrene (ABS) print by fused deposition modelling (FDM). The mechanical properties of ABS are highly influenced by printing parameters, and they determine the final product quality of printed pieces. Design/methodology/approach: For the paper’s purpose, five main parameters (extrusion temperature, infill pattern, air gap, printing speed and layer thickness) were selected and varied during ABS printing on an open-source and self-replicable FDM printer. Three different colors of commercially available ABS were also used to investigate color and printing parameter’s influence on the tensile strength. Findings: The research results suggest that two parameters (infill pattern and layer thickness) were most influential on the mechanical properties of print ABS, being able to enhance its tensile strength. Another key influential factor was material color selected prior to printing, which influenced the tensile strength of the print specimen. Originality/value: This study provides information on print parameters’ influence on the tensile strength of ABS print on replicable open-source three-dimensional (3D) printers. It also suggests the influence of materials’ color on print pieces’ tensile strength, indicating a new parameter for materials selection for 3D printing. Department of Mechanical Engineering Bauru School of Engineering Sao Paulo State University – UNESP Federal Institute of Education Science and Technology of São Paulo Birigui Brazil and Department of Mechanical Engineering School of Engineering Sao Paulo State University – UNESP Department of Arts and Graphic Representation School of Architecture Arts and Communication Sao Paulo State University – UNESP Department of Mechanical Engineering Bauru School of Engineering Sao Paulo State University – UNESP Federal Institute of Education Science and Technology of São Paulo Birigui Brazil and Department of Mechanical Engineering School of Engineering Sao Paulo State University – UNESP Department of Arts and Graphic Representation School of Architecture Arts and Communication Sao Paulo State University – UNESP

Biofilm at water-oil interface of hypoxic water columns of microcosms, prepared from a lacustrine sample, that used diesel as a carbon source was found to show electrogenic properties. These microcosms named, Liquid Microbial Fuel Cells (L-MFCs) were electrically characterized using a custom electronic analyzer; accurate determination of voltage (V), power density (W/m 2), and current density (A/m2) for both charge and discharge phases was carried out. The instrument made it possible to carry out cell characterizations using resistive loads between 0 Ω (Ohm) and 10 kΩ. During the hypoxic and electrogenic phase, the synthesis of a system of "bacterial piping induction", produced filaments of hundreds of micrometers in which the microbial cells are hosted. Ultrastructural microscopy collected by scanning (SEM), transmission (TEM), immunofluorescence, Thunder Imager 3D, confocal laser scanning (CLSM) microscopy revealed a "myelin like" structure during filamentation processes; this "myelin like" structure exhibited cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The disclosure of these filamentation processes could be helpful to describe further unconventional microbial structures in aquatic ecosystems and of the animal world. The data that support the findings of this study are openly available in at https://data.mendeley.com/datasets/7d35tj3j96/1.

Acrylonitrile butadiene styrene (ABS) is the most commonly used thermoplastic printing material for fused deposition modelling (FDM). FDM ABS can be used in a variety of complex working environments. Notably, the thermo-mechanical coupled loads under complex operating conditions may lead to cracking and ultimately catastrophic structural failure. Therefore, it is crucial to determine the crack depth and location before a structural fracture occurs. As these parameters affect the dynamic response of the structure, in this study, the fundamental frequency and displacement amplitude response of a cracked 3D-printed ABS cantilever beam in a thermal environment were analytically and experimentally investigated. The existing analytical model, specifically the torsional spring model used to calculate the fundamental frequency change to determine the crack depth and location was enhanced by the proposed Khan-He model. The analytical relationship between the displacement amplitude and crack was established in Khan-He model and validated for the first time for FDM ABS. The results show that a reduced crack depth and location farther from the fixed end correspond to a higher fundamental frequency and displacement amplitude. An elevated ambient temperature decreases the global elastic modulus of the cracked beam and results in a lower fundamental frequency. Moreover, a non-monotonic relationship exists between the displacement amplitude and ambient temperature. The displacement amplitude is more sensitive to the crack change than the fundamental frequency in the initial stages of crack growth.

In the automotive industry, the measurement, control and reproducibility of certain morphological characteristics of surfaces are important to characterize, qualify, certify and optimize different physical properties, such as the degree of wear, the degree of adhesion by adhesives, glues or paints and optical properties. In this regard, this work is intended demonstrate how it is possible to characterize different surfaces in ABS (Acrylonitrile Butadiene Styrene) and PC-ABS (PolyCarbonate/Acrylonitrile Butadiene Styrene) through a set of morphological parameters defined according to the ISO 25178 standard. These surfaces have been subjected to different etching treatments performed with different chemicals, which can radically modify the morphology of the surface, making it more or less suitable according to the industrial purposes sought. Furthermore, in this work an analytical relationship between the hybrid parameters Sdq and Sdr defined in the ISO-25718 standard is also proposed, valid for many surfaces of general use. This study is based on the use of a confocal optical microscope and a SEM (Scanning Electron Microscope), which allow surface morphology to be studied at the micro/nano scale and the measurements are analyzed with special imaging and three-dimensional scanning software that allows the precise measurement of morphological parameters of the standard ISO-25178.

Bakalaureusetöö Tehnika ja tehnoloogia õppekaval Eelnevate lõputööde raames on konstrueeritud järeltöötluskamber ning on uuritud, kuidas mõjutab atsetooniga järeltöötlemine 3D prinditud ABS detailide pinnaviimistlust ja täpsust. Käesoleva töö eesmärgiks oli uurida atsetooniga järeltöötlemise mõju 3D prinditud ABS detailide mehaanilistele omadustele. 3D printimiseks kasutati EMÜ Tehnikamaja mõõtelaboris asuvat Ultimaker 3 printerit. Kokku 3D prinditi 20 katsekeha. Atsetooniga järeltöötlemine toimus eelnevate lõputööde raames konstrueeritud seadmega. Järeltöötlemine toimus samasugustel tingimustel, mis on toodud Hans Eduard Säre lõputöös. Järeltöötlusajad olid 5, 15, 30, 45 ja 60 minutit. Katsekehad järeltöödeldi partiidena, kus ühes partiis oli kolm katsekeha. Tõmbekatsetega määrati järeltöödeldud ja järeltöötlemata katsekehade mehaanilised omadused. Tulemused näitasid, et atsetooniga järeltöötlemine vähendas ABS materjali tõmbetugevust ja voolepiiri. Kõige enam vähenesid tõmbetugevus ja voolepiir katsekehadel, mille järeltöötlusaeg oli 30 minutit. Pikenemine voolepiiril ja pikenemine purunemisel suurenesid järeltöötlusaegadel 30, 45 ja 60 minutit. Atsetooniga järeltöötlemine suurendas 3D prinditud ABS materjali elastsusmoodulit ja katkevenivust järeltöötlusaegadel 15 ja 30 minutit. As part of the previous dissertations, a post-processing chamber was designed and the effect of acetone post-treatment on the surface finish and accuracy of 3D printed ABS parts was investigated. The aim of this study was to investigate the effect of acetone finishing on the mechanical properties of 3D printed ABS parts. The Ultimaker 3 printer in the EEC laboratory was used for 3D printing. A total of 20 specimens were printed. The post-treatment with acetone took place in a post-treatment plant designed as part of the previous final work. The post-processing took place under the same conditions as in Hans Eduard Säre's thesis. Finishing times were: 5, 15, 30, 45 and 60 minutes. The test pieces were post-processed in batches, one batch containing three test pieces. During the tensile tests, the mechanical properties of the post-treated as well as untreated test pieces were observed. The results show that properties such as tensile strength and yield strength decrease after treatment with acetone, regardless of time. The greatest decrease occurred in test specimens that were post-treated for 30 minutes. Indices such as fracture at break and elongation at break improved when the specimens were post-treated for 30, 45 and 60 minutes. The effect of acetone treatment on modulus of elasticity and elongation at break was most effective at 15 min and 30 min. The results show that the longer the test bed is post-processed, the greater the decrease in tensile strength and yield strength.

Most of what scientists discovered about biodiversity and published, totaling a corpus of an estimated 500 million printed pages stacked up in our libraries and more recently, in digital format, is not known. It is an amount of information that can not be processed by humans, but even machines can’t cope with it because the publications are either not scanned, or are behind paywalls, or in formats that machines can’t read at scale. It is a tragedy that in this digital age we can’t make use of this data. But it doesn’t need to be like this. Scientific publications are structured, they use standard means to express the results. Arguments cite previous arguments building a network of knowledge. If represented digitally, this knowledge could be represented as a knowledge graph and analysed. The data in publications can be made FAIR: Figures, blocks of texts such as the descriptions of species, or material citations; named entities such as person or taxonomic names can be annotated and linked to reference vocabularies. They can be cited and reused irrespective whether a publication is behind closed doors. In an exemplary way this lecture will show the collaboration between theBiodiversity Literature Repositoryand theGlobal Biodiversity Information Facilitythat has made available data about80,000 speciesknown in GBIF only because they have been liberated from the publications, thereby enabling the sharing of this scientific knowledge with anybody, anywhere for any purpose. Open FAIR data * represent knowledge about biodiversity, i.e.g what we know about a gene, specimen, species as well as assess a gene, specimen in its scientific knowledge, and allows exploring by machine * is basis for conservation, biodiversity research, society, CBD’s post 2020 Global Biodiversity Framework * depends on complex infrastructures, funding, collaborations producing FAIR data that * can be used anywhere, at any time by anyone by human or machine. * increased by accelerating switching to advanced semantically enhanced publishing * needs massive amounts of teaching how to use the results and create innovations *Access and Benefit Sharing (ABS): Open FAIR access as part of benefit sharing &nbsp

The article presents the results of research on the influence of the natural moisture of a filament made of acrylonitrile–butadiene–styrene terpolymer (ABS) on the mechanical properties and quality of products fabricated with fused filament fabrication (FFF). The concept of the natural moisture of the filament was defined, and the range of its variability was identified in reference to the range of the natural ambient humidity. It is shown that a change in the ambient humidity by 10% resulted in a change in filament moisture by about 0.05%. The results of the research on the moisture variability of an ABS filament stored in a package, an airtight container, or a container with a moisture absorber are also discussed. The last part of the article presents the results of the research on the impact of the moisture of the filament in its natural range of variability on select mechanical properties of filaments and products made using FFT. It is shown that this impact was significant and had a value of 1 MPa on 0.1% filament moisture.

AddJoining technique has been recently introduced to produce metal–polymer composite hybrid layered structures. The methodology combines the principles of joining and polymeric additive manufacturing. This paper presents three AddJoining process-variants investigated and demonstrated for the material combination aluminum 2024-T3 and acrylonitrile butadiene styrene to form hybrid single lap joints. The microstructure and mechanical performance were assessed. The process variant using heating control showed the ultimate lap shear force of 1.2 ± 0.05 kN and displacement at a break of 1.21 ± 0.16 mm as a result of strong bonding formation at the interface of the hybrid joints. For instance, the other two process variants tested (with epoxy adhesive, and with thin-acrylonitrile butadiene styrene (ABS) coating layer applied on the metal) presented reduced mechanical performance in comparison to process variant using heating control, namely approximately 42% and 8.3%, respectively. The former had a mixed adhesive–cohesive failure due to the lower bonding performance between the adhesive and ABS printed layers. The latter displayed a slight decrease in force in comparison to heat-control specimens. This could be explained by the presence of micro-voids formed by solvent evaporation at the ABS coating layer during AddJoining.

Producing parts by 3D printing based on the material extrusion process determines the formation of air gaps within layers even at full infill density, while external pores can appear between adjacent layers making prints permeable. For the 3D-printed medical devices, this open porosity leads to the infiltration of disinfectant solutions and body fluids, which might pose safety issues. In this context, this research purpose is threefold. It investigates which 3D printing parameter settings are able to block or reduce permeation, and it experimentally analyzes if the disinfectants and the medical decontamination procedure degrade the mechanical properties of 3D-printed parts. Then, it studies acetone surface treatment as a solution to avoid disinfectants infiltration. The absorption tests results indicate the necessity of applying post-processing operations for the reusable 3D-printed medical devices as no manufacturing settings can ensure enough protection against fluid intake. However, some parameter settings were proven to enhance the sealing, in this sense the layer thickness being the most important factor. The experimental outcomes also show a decrease in the mechanical performance of 3D-printed ABS (acrylonitrile butadiene styrene) instruments treated by acetone cold vapors and then medical decontaminated (disinfected, cleaned, and sterilized by hydrogen peroxide gas plasma sterilization) in comparison to the control prints. These results should be acknowledged when designing and 3D printing medical instruments.

This research focuses on thermal deformations of thermoplast during three-dimensional printing. A filament acrylonitrile butadiene styrene was used, and the main focus was put on warping. Twenty-seven cuboids divided in six categories by their length, height, surface area, color, nozzle temperature and bed temperature were printed by Fused Filament Fabrication 3D printer. The whole process was captured by a thermal camera and the movies were used to analyze the temperature distribution during printing. All printouts were measured and scanned with a 3D scanner in order to highlight any abbreviations from the original digital models. The obtained results were used to formulate some general conclusions on the influence of selected parameters on the warping process. Based on the outcomes of the study, a set of guidelines on how to minimalize warping was proposed.

Bicycle forks are prone to bending, introducing a flexible structure between front wheel and vehicle body. This has substantial influence on brake control, not only by altering the system dynamics ...

The paper considers a method for calculation and evaluation of an automated brake proportioning system and it also describes assessment of efficiency while using cohesion forces of an automated system during vehicle braking process (MAZ 256200 taken as an example). A method for efficiency estimation of the vehicle braking equipped with an automated brake proportioning system is graphically presented in the paper. A comparable analysis has been made in order to evaluate vehicle braking efficiency in three various conditions of its wheel motion during braking process. The paper contains description of braking processes for a vehicle at its idealized braking, at braking with an operating automated system and at braking with blocked wheels. Mathematical dependences have been proposed and they make it possible to calculate a coefficient of cohesion forces used by an automated brake proportioning system on the basis of time parameters for vehicle braking process. The proposed mathematical dependences take into account design peculiarities of the automated system, i.e. a diagram of modulator arrangement on axes of the vehicle. The executed analysis for calculation accuracy of the coefficient pertaining to use of cohesion forces of the automated system with and without taking into accout rolling force resistance of the vehicle wheels has demonstrated a possibility to apply the proposed calculation methods for carrying out auto-technical expertise while investigating road-traffic accidents involving transport facilities equipped with such systems as ABS. The paper proposes a dependence for identification of a vehicle braking distance on the basis of the coefficient on use of cohesion forces by the automated brake proportioning system. The executed experimental investigations on both test and serial models of the automated brake proportioning system have allowed to justify theoretical discussions concerning application of tyre-road adhesion in the operational process of the vehicle brake proportioning system. The investigation results have shown high efficiency of the test automated brake proportioning system developed by Chair of Automobiles in the name of A. B. Hredescul at Kharkiv National Automobile and Road University under the following braking conditions: dry road surface and compacted snow cover.

In this paper, an adaptive algorithm is developed which senses the road condition change and estimates a (time-varying) optimal braking slip ratio. This is conducted by two on-line simultaneously operating tire-road friction-curve slope calculators: one based on the accelerometer output and the other based on the wheel speed. The required vehicle speed is estimated using a robust sliding-mode observer. Enforcement of the online optimal braking reference is left to an adaptive sliding mode controller to cope with the system strong nonlinearity, time dependency and the speed and friction-coefficient estimation errors. The algorithm is applied to a half model car and the braking performance is examined. The results indicate that the proposed algorithm substantially reduces the stopping time and distance. The performance of the algorithm is verified using different vehicle initial speeds and especially non-uniform road condition where 8% improvement versus the nonadaptive optimal slip ratio algorithm is recorded.

The simulation and modelling paradigms have significantly shifted in recent years under the influence of the Industry 4.0 concept. There is a requirement for a much higher level of detail and a lower level of abstraction within the simulation of a modelled system that continuously develops. Consequently, higher demands are placed on the construction of automated process models. Such a possibility is provided by automated process discovery techniques. Thus, the paper aims to investigate the performance of automated process discovery techniques within the controlled environment. The presented paper aims to benchmark the automated discovery techniques regarding realistic simulation models within the controlled environment and, more specifically, the logistics process of a manufacturing company. The study is based on a hybrid simulation of logistics in a manufacturing company that implemented the AnyLogic framework. The hybrid simulation is modelled using the BPMN notation using BIMP, the business process modelling software, to acquire data in the form of event logs. Next, five chosen automated process discovery techniques are applied to the event logs, and the results are evaluated. Based on the evaluation of benchmark results received using the chosen discovery algorithms, it is evident that the discovery algorithms have a better overall performance using more extensive event logs both in terms of fitness and precision. Nevertheless, the discovery techniques perform better in the case of smaller data sets, with less complex process models. Typically, automated discovery techniques have to address scalability issues due to the high amount of data present in the logs. However, as demonstrated, the process discovery techniques can also encounter issues of opposite nature. While discovery techniques typically have to address scalability issues due to large datasets, in the case of companies with long delivery cycles, long processing times and parallel production, which is common for the industrial sector, they have to address issues with incompleteness and lack of information in datasets. The management of business companies is becoming essential for companies to stay competitive through efficiency. The issues encountered within the simulation model will be amplified through both vertical and horizontal integration of the supply chain within the Industry 4.0. The impact of vertical integration in the BPMN model and the chosen case identifier is demonstrated. Without the assumption of smart manufacturing, it would be impossible to use a single case identifier throughout the entire simulation. The entire process would have to be divided into several subprocesses.

Thermoplastic composite materials are emerging rapidly due to the flexibility of attaining customized mechanical and melt flow properties. Due to high ductility, toughness, recyclability, and thermal and electrical conductivity, there is ample scope of using copper particles in thermoplastics for 3d printing applications. In the present study, an attempt was made to investigate the Melt Flow Index (MFI), tensile strength, and electrical and thermal conductivity of nylon 6 and ABS (acrylonitrile butadiene styrene) thermoplastics reinforced with copper particles. Thus, the experiments were conducted by adding different-sized copper particles (100 mesh, 200 mesh, and 400 mesh) in variable compositions (0% to 10%) to ABS and nylon 6 matrix. The impact of single, double, and triple particle-sized copper particles on MFI was experimentally investigated followed by FTIR and SEM analysis. Also, the tensile, electrical, and thermal conductivity testing were done on filament made by different compositions. In general, higher fluidity and mechanical strength were obtained while using smaller particles even with higher concentrations (up to 8%) due to improved bonding strength and adhesion between the molecular chains. Moreover, thermal and electrical conductivity was improved with an increase in concentration of copper particles.

The outburst of plastic pollution in terrestrial ecosystems poses a potential threat to agriculture and food safety. Studies have already provided evidence for the uptake of plastic microparticles by several plant species, accompanied by numerous developmental effects, using fluorescence labelling techniques. Here, we introduce the implementation of confocal Raman spectroscopy, a label-free method, for the effective detection of microplastics (MPs) accumulation in the roots of a common edible root vegetable plant, Raphanus sativus, after treatment with acrylonitrile butadiene styrene (ABS) powder. We also demonstrate the concomitant occurrence of phenotypic defects in the polymer-treated plants. We anticipate that this work can provide new insights not only into the extent of the impact this widespread phenomenon has on crop plants but also on the methodological requirements to address it.

Fracture mechanics are of high interest for the engineering design and structural integrity assessment of polymeric materials, however, regarding highly ductile polymers, many open questions still remain in terms of fully understanding deformation and fracture behaviors. For example, the influence of the constraint and specimen size on the fracture behavior of polymeric materials is still not clear. In this study, a polymeric material with an elastic plastic deformation behavior (ABS, acrylonitrile butadiene styrene) is investigated with regard to the influence of constraint and specimen size. Different single-edge notched bending (SENB) specimen sizes with constant geometrical ratios were tested. The material key curve was used to investigate differences in the constraint, where changes for small and large specimen sizes were found. Based on a size-independent crack resistance curve (J–R curve), two apparent initiation parameters (J0.2 and Jbl) were determined, namely, the initiation parameter Jini (based on the crack propagation kinetics curve) and the initiation parameter JI,lim (based on an ESIS TC 4 draft protocol). It was found that J0.2 and Jbl could be used as crack initiation parameters whereby Jini and JI,lim are indicative of the onset of stable crack growth.

En este proyecto se ha estudiado el comportamiento frente a la degradación de dos materiales termoplásticos biodegradables fabricados mediante impresión 3D: Enviro ABS y PLA. Se ha simulado la acción del sol y del agua del mar para descubrir cómo afectan a las propiedades de estos materiales durante el tiempo. Se han recogido datos de límite elástico, elongación máxima, tensión máxima soportada, microscopía además de llevar un seguimiento de sus dimensiones y masa. Se estudiarán estos materiales biodegradables para concluir si existe una alternativa ecológica al ABS tradicional, al ser uno de los plásticos derivados del petróleo más utilizado en la fabricación por tecnología FDM. El estudio consta de ocho semanas en las cuales se muestran las diferencias en las propiedades de estudios frente a la degradación en ambos medios a lo largo del tiempo. Se observa que el PLA muestra una pérdida de peso y aumento de la tensión máxima en la degradación mediante luz solar y una disminución prolongada de la tensión máxima en la degradación mediante agua de mar debido a la absorción de humedad; en cambio, el Enviro ABS no muestra una notoria diferencia entre el comienzo y el final del ensayo lo que deja concluir que el Enviro ABS es una buena alternativa al ABS convencional sin olvidar los efectos medioambientales que conllevan en la actualidad la fabricación, reciclaje y compostaje de este tipo de materiales.

We present a social simulation model that covers three main financial services: Banks, Retail Stores, and Payments systems. Our aim is to address the problem of a lack of public data sets for fraud detection research in each of these domains, and provide a variety of fraud scenarios such as money laundering, sales fraud (based on refunds and discounts), and credit card fraud. Currently, there is a general lack of public research concerning fraud detection in the financial domains in general and these three in particular. One reason for this is the secrecy and sensitivity of the customers data that is needed to perform research. We present PaySim, RetSim, and BankSim as three case studies of social simulations for financial transactions using agent-based modelling. These simulators enable us to generate synthetic transaction data of normal behaviour of customers, and also known fraudulent behaviour. This synthetic data can be used to further advance fraud detection research, without leaking sensitive information about the underlying data. Using statistics and social network analysis (SNA) on real data we can calibrate the relations between staff and customers, and generate realistic synthetic data sets. The generated data represents real world scenarios that are found in the original data with the added benefit that this data can be shared with other researchers for testing similar detection methods without concerns for privacy and other restrictions present when using the original data.

In this work, polyamide 6 (PA6) properties were tailored and improved using a maleic anhydride-grafted acrylonitrile-butadiene-styrene terpolymer (ABS-MA). The PA6/ABS-MA blends were prepared using a co-rotational twin-screw extruder. Subsequently, the extruded pellets were injection-molded. Blends were characterized by torque rheometry, the Molau test, Fourier transform infrared spectroscopy (FTIR), impact strength, tensile strength, Heat Deflection Temperature (HDT), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Contact Angle, Scanning Electron Microscopy (SEM), and water absorption experiments. The most significant balance of properties, within the analyzed content range (5, 7.5, and 10 wt.%), was obtained for the PA6/ABS-MA (10%) blend, indicating that even low concentrations of ABS-MA can improve the properties of PA6. Significant increases in impact strength and elongation at break have been achieved compared with PA6. The elastic modulus, tensile strength, HDT, and thermal stability properties of the PA6/ABS-MA blends remained at high levels, indicating that maleic anhydride interacted with amine end-groups of PA6. Torque rheometry, the Molau test, and SEM analysis suggested interactions in the PA6/ABS-MA system, confirming the high properties obtained. Additionally, there was a decrease in water absorption and the diffusion coefficient of the PA6/ABS-MA blends, corroborating the contact angle analysis.

This paper provides a methodology for the prediction of fracture loads in additively manufactured ABS material containing U-notches. The approach is based on the Average Strain Energy Density (ASED) criterion, which assumes that the material being analysed develops fully linear-elastic behaviour. Thus, in those cases where the material has a certain (non-negligible) amount of non-linear behaviour, the ASED criterion needs to be corrected. In this sense, in this paper, the ASED criterion is also combined with the Equivalent Material Concept (EMC) and the Fictitious Material Concept (FMC), both being corrections in which the non-linear real material is substituted by a linear equivalent or fictitious material, respectively. The resulting methodologies have been applied to additively manufactured ABS U-notched single-edge-notched bending (SENB) pecimens combining five different notch radii (0, 0.25, 0.5, 1 and 2 mm) and three different raster orientations (0/90, 45/-45 and 30/-60). The results obtained demonstrate that both the ASED-EMC and the ASED-FMC combined criteria provide more accurate predictions than those obtained directly through the ASED criterion, with the ASED-EMC criterion generally providing safe more accurate predictions, with an average deviation from the experimental fracture loads between +1.0% (predicted loads higher than experimental loads) and -7.6% (predicted loads lower than experimental loads). This publication is part of the project “Comportamiento en fractura de materiales compuestos nano-reforzados con defectos tipo entalla, PGC2018-095400-B-I00” funded by MCIN/ AEI/10.13039/501100011033/ FEDER “Una manera de hacer Europa”

Currently, 3D printing is an affordable technology for industry, healthcare, and individuals. Understanding the mechanical properties and thermoplastic behaviour of the composites is critical for the users. Our results give guidance for certain target groups including professionals in the field of additive manufacturing for biomedical components with in-depth characterisation of the examined commercially available ABS and PLA carbon-based composites. The study aimed to characterize these materials in terms of thermal behaviour and structure. The result of the heating-cooling loops is the thermal hysteresis effect of Ohmic resistance with its accommodation property in the temperature range of 20&ndash, 84 &deg, C for ESD-ABS and 20&ndash, 72 &deg, C for ESD-PLA. DSC-TGA measurements showed that the carbon content of the examined ESD samples is ~10&ndash, 20% (m/m) and there is no significant difference in the thermodynamic behaviour of the basic ABS/PLA samples and their ESD compounds within the temperature range typically used for 3D printing. The results support the detailed design process of 3D-printed electrical components and prove that ABS and PLA carbon composites are suitable for prototyping and the production of biomedical sensors.

Fullerol (C60OH) has been shown to catalyze the trisodium citrate (TSC)–silver nitrate reaction to generate Ag nanoparticles (AgNPs). These AgNPs exhibit significant nanoplasmic surface-enhanced Raman scattering (SERS), resonance Rayleigh scattering (RRS), and absorption (Abs). When an aptamer (Apt) adsorbs on the C60OH surface, catalysis is inhibited, and the intensities of SERS, RRS, and Abs decrease. In the presence of isocarbophos (IPS), Apt forms a stable complex (Apt-IPS) and releases C60OH. As a result, SERS, RRS, and Abs intensities increase with increasing IPS concentration. Accordingly, a new SERS, RRS, and Abs trimodal method using Apt-labeled fullerol was established for the determination of IPS. Of the three spectral methods, SERS was the most sensitive, while the Abs method was the most cost-effective.

Целью исследования является выявление и оценка сильных и слабых сторон различных путей автоматизации кредитных организаций, их способности противостоять возможностям и угрозам внешней среды. Полученные в результате исследования матрицы количественного SWOT-анализа позволяют лицам, принимающим решения в области стратегического управления информационными технологиями в кредитных организациях, более взвешенно подходить к выбору пути развития. Сравнительный анализ SWOT-матриц для разных путей автоматизации позволяет сделать вывод о предпочтительности использования систем класса ERP в качестве базовой платформы для автоматизации в банке., Usage of automated informational systems in the daily activities of a financial institution is the basis of its successful existence and development. The most common ways of automation in the financial sector based on own development or standard of automated banking systems (ABS) are no longer able to meet the increasing needs. That is why the use of successfully operating in other industries ERP systems becomes very attractive. For today, many researches has been done on the existing market of banking systems. There are also works describing the advantages of using ERP systems for automation of economic activities of the bank. Nevertheless, it is quite difficult to make a choice about strategy of automation. The aim of the study is to identify and assess the strengths and weaknesses of each of the ways of automation and their ability to withstand the opportunities and threats of environmental factors. The method of quantitative SWOT analysis based on expert assessments was used for this study. The quantitative SWOT analysis matrices had been obtained because the study allow decision-makers in the field of IT strategy to have a more balanced approach to the choice of the development path. Comparison of SWOT matrices for analysis of automation paths allows making a conclusion about the preference of using ERP system as a basic system in the bank.

Polymer blends are capable of providing materials with extended useful properties beyond the range that can be obtained from single polymer. Blends of polystyrene (PS) and polypropylene (PP) with adding acrylonitrile-butadiene-styrene (ABS) or ethylene propylene diene monomer (EPDM) are prepared in different ratios by melt blending technique which was carried out using a double screw extruder. The tensile, flexural, impact and hardness tests of all the prepared samples were study. The results from this work show that the elongation property and impact properties for blend system increase with increase PP content in polymer blend of (PS:PP), also increase value of these properties with increase the ratio of adding (ABS or EPDM) for polymer blend (PS:5%PP).The highest values of impact strength was (10.68Kj/m2 ) for ternary polymers blend (90%PS:5%PP:5%EPDM) and the high values of fracture toughness (6.125MPa√m ) for ternaty polymer blend (90%PS:5%PP:5%ABS).

The ability to predict the phase equilibria behavior is of crucial relevance in the early design stage of biphasic liquid-liquid systems. Ionic liquid-based aqueous biphasic systems (IL-ABS) have demonstrated superior performance in many applications such as the recovery of bio-products and the recycling of hydrophilic ILs from aqueous solutions. In order to better utilize these novel biphasic liquid-liquid systems, modelling studies on phase equilibria behavior are carried out in this work. First, the IL database developed in our previous work is extended to these unconventional biphasic systems. In total, 17,449 experimental binodal data points covering 171 IL-ABS at different temperatures (278.15 K-343.15 K) are collected. Then, all involved IL-ABS are correlated using a popular three-parameter mathematical description and the optimal parameters of each IL-ABS are obtained. Afterwards, we try to build a linear group contribution (GC) model to predict the phase equilibria behavior of IL-ABS, but it fails due to the high complexity of these biphasic systems. For this reason, we finally turn to applying a well-known machine learning algorithm, i.e., artificial neural network (ANN), to build a nonlinear GC model for such a purpose. This model gives a mean absolute error (MAE) of 0.0175 and squared correlation coefficient (R2) of 0.9316 for the 13,789 training data points, and for the 3,660 test data points they are 0.0177 and 0.9195, respectively. The results indicate that the proposed nonlinear ANN-GC model, to some extent, is capable to predict the phase equilibria behavior of IL-ABS. Besides the efforts of building GC models, we also discuss some main issues that govern the phase equilibria behavior of IL- ABS, which could be a guidance in the design of IL-ABS.

In this work, magnetron sputtered CrNx thin films with nitrogen concentrations ranging from 17 to 30 at.% were deposited on plasma activated ABS. Two sets of thin films were obtained by varying the N-2 flow inside the vacuum chamber (series #1) and the deposition time (series #2). The polymer samples were also subjected to plasma treatment in Ar prior to the CrNx thin films' deposition, in order to enhance the adhesion. The fundamental microstructural, chemical and physical properties, as well as the electrochemical and adhesion behavior of the CrNx thin films, were assessed by SEM, XRD, 3D profilometry, RAMAN, colorimetry, OCP measurements and cross-cut tape test. Main results show that high-quality CrNx films with a low percentage of defects were obtained. The CrNx film sputtered with 3 sccm N-2 for 20 min was considered to possess the most appropriate brightness, color, electrochemical stability and interfacial adhesion to fit the end-user requirements. Magnetron sputtering is thus a promising alternative to the hazardous chrome plating for an effective metallization of ABS., This work was developed within the scope of the project POCI-01-0247-FEDER-003493 co-financed by FEDER through the POCI program and project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT ref. UID/CTM/50011/2013), financed by national funds through FCT and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement., info:eu-repo/semantics/publishedVersion

The present work investigates the fire retardancy mechanisms of ammonium polyphosphate (APP) and aluminium diethyl phosphinate salt (AlPi) in an acrylonitrile-butadiene-styrene copolymer (ABS) by analysing the pyrolysis, flammability and fire behaviour. Evidences of synergy in flammability by combining both flame retardants were discussed and related to the flame retardant mechanisms assessed by means of TGA and FT-IR analysis of the pyrolysis gases. Specifically, the ABS flame retardant formulation with a 12.5 wt% APP and 12.5 wt% AlPi (ABS-APP/AlPi) reached a UL-94 V-0 classification, unlike the ABS with 25 wt% APP (ABS-APP) and ABS with 25 wt% AlPi (ABS-AlPi) formulations, which completely burned. Under forced flame conditions, APP and AlPi showed, respectively, a main condensed and gas phase-based mode of action in the ABS matrix, whereas, a combined gas and condensed mode of action was identified when both additives were simultaneously incorporated. Also, the ABS-APP/AlPi formulation showed the higher reduction of the peak heat release rate (74%) and of the maximum average rate of heat emission (65%), obtained from cone calorimeter tests. As well as, a more protective fire residue with an improved microstructure assed by SEM.

This paper presents the use of 3D printing and discusses two types of materials used in 3D printing, ie ABS (Acrylonitrile butadiene styrene) and PLA (Polylactide). Next, presents thermovisual measurement were carried out on 3D printed samples (FDM method - fused deposition modelling) of these materials. The temperature zones that occurred during printing were determined. The geometrical dimensions of samples from the same material that were printed under different conditions were compared. The height of the printed object has a large influence on the temperature distribution on its surface and The printing time does not differ significantly when printing from PLA and ABS.

International audience; Material key curves are functions providing a relationship among load, displacement and crack size, and are used in fracture mechanics methods for ductile polymers. This work shows that the material key curves provide also a tool to distinguish among different deformational mechanisms involved in the fracture process and they reflect the constraint degree. Tests are carried out on an acrylonitrile-butadiene-styrene resin (ABS) as a model material, and different deformation mechanisms are induced by different temperatures and loading rates, up to impact conditions. Deformation mechanisms are investigated, for the first time on ABS, by tomography and the results are compared to more traditional imaging techniques as scanning and transmission electron microscopy.

Purpose The purpose of this paper is to characterize the effects of different micro particle reinforcement with same weight ratio in acrylonitrile-butadiene-styrene (ABS) feed-stocks for 3D printing process. Design/methodology/approach In this study, composite filaments were produced by using a co-rotational twin screw extruder and used as building material to print samples in a commercial fused deposition modeling (FDM) 3D printer. The reinforcement particles, ZrB2 and Al, have different properties, including density, surface area, purity and particle morphology, and were expected to improve mechanical properties of 3D printed samples. Differential calorimetry scanning and melt flow index studies were applied on the materials to observe the change in glass transition temperatures and melt flow behaviors, respectively. Also, to evaluate the mechanical properties, tensile and three-point bending test were carried out. Fractured surfaces were characterized via energy-dispersive X-ray spectroscopy for validation of the reinforcements in the ABS matrix. Moreover, scanning electron microscope micrograph examination was conducted on the fractured surfaces to characterize fracture modes. Findings For 3D printed samples, a strain increase of at least 82.5 per cent was achieved by using micro particle reinforcement with a weight ratio of 1.5 per cent. Research limitations/implications Higher filler ratios of the reinforcement particles cause loss on the printability of the feed-stocks. Practical implications Reinforced ABS stands out as a possible solution to overcome robustness problems in FDM printing. Originality/value Even though the effects of printing parameters on the mechanical properties of 3D printed parts have been vastly studied in the literature, studies conducted on improvement of the building materials are limited. This paper proposes to create novel feed-stock materials for achieving printed parts with superior properties using polymer composites.

The growing use of Unmanned Aerial Vehicles (UAVs) for various applications requires ubiquitous and reliable connectivity for safe control and data exchange between these devices and ground terminals. Depending on the application, UAV-mounted wireless equipment can either be an aerial user equipment (AUE) that co-exists with the terrestrial users, or it can be a part of wireless infrastructure providing a range of services to the ground users. For instance, AUE can be used for real-time search and rescue and Aerial Base Station (ABS) can enhance coverage, capacity and energy efficiency of wireless networks. In both cases, UAV-based solutions are scalable, mobile, fast to deploy. However, several technical challenges have to be addressed. In this work, we present a tutorial on wireless communication with UAVs, taking into account a wide range of potential applications. The main goal of this work is to provide a complete overview of the main scenarios (AUE and ABS), channel and performance models, compare them, and discuss open research points. This work gives a comprehensive overview of the research done until now and depicts a comprehensive picture to foster new ideas and solutions while avoiding duplication of past work. We start by discussing the open challenges of wireless communication with UAVs. To give answers to the posed questions, we focus on the UAV communication basics, mainly providing the necessary channel modeling background and giving guidelines on how various channel models should be used. Next, theoretical, simulation- and measurement-based approaches, to address the key challenges for AUE usage, are presented. Moreover, in this work, we aim to provide a comprehensive overview on how UAV-mounted equipment can be used as a part of a communication network. Based on the theoretical analysis, we show how various network parameters can be optimized., Comment: 42 pages, 32 Figures

This paper explores a coordinated control strategy of the anti-lock braking system (ABS) for in-wheel motors driven electric vehicles to recover more braking energy while satisfying the target of slip ratio control based on a newly varying charge voltage in steps control (VCVISC). The novel VCVISC method is proposed on the existing battery management system to change the charging voltage by choosing the number of batteries in the series to substitute for the converter. The reason that the conventional linear quadratic Gaussian (LQG) control employed in ABS control does not function is examined by theoretical derivation, and an improved LQG scheme is presented to calculate the real-time required braking torque by adding virtual damping and infinitely small terms in the Riccati equation. A distributing strategy of braking torque is presented to maximize the energy recovery, which is realized by using the VCVISC method to regulate the regenerative braking torque in real time. Simulation results under different braking road scenarios demonstrate that the proposed ABS control strategy can achieve not only an outstanding response for tracking ideal slip ratio, but also an efficient braking energy recovery efficiency.