bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Acetylated SEBS/PP for Potential HVDC Cable Insulation
Authors: Zhang Peng , Zhang Yongqi , Wang Xuan , Yang Jiaming , Han Wenbin
Published: March 2021

Blending thermoplastic elastomers into polypropylene (PP) can make it have great potential for high-voltage direct current (HVDC) cable insulation by improving its toughness. However, when a large amount of thermoplastic elastomer is blended, the electrical strength of PP will be decreased consequently, which cannot meet the electrical requirements of HVDC cables. To solve this problem, in this paper, the inherent structure of thermoplastic elastomer SEBS was used to construct acetophenone structural units on its benzene ring through Friedel–Crafts acylation, making it a voltage stabilizer that can enhance the electrical strength of the polymer. The DC electrical insulation properties and mechanical properties of acetylated SEBS (Ac-SEBS)/PP were investigated in this paper. The results showed that by doping 30% Ac-SEBS into PP, the acetophenone structural unit on Ac-SEBS remarkably increased the DC breakdown field strength of SEBS/PP by absorbing high-energy electrons. When the degree of acetylation reached 4.6%, the DC breakdown field strength of Ac-SEBS/ PP increased by 22.4% and was a little higher than that of PP. Ac-SEBS, with high electron affinity, is also able to reduce carrier mobility through electron capture, resulting in lower conductivity currents in SEBS/PP and suppressing space charge accumulation to a certain extent, which enhances the insulation properties. Besides, the highly flexible Ac-SEBS can maintain the toughening effect of SEBS, resulting in a remarkable increase in the tensile strength and elongation at the break of PP. Therefore, Ac-SEBS/PP blends possess excellent insulation properties and mechanical properties simultaneously, which are promising as insulation materials for HVDC cables.
On the Ninth Coefficient of the Inverse of a Convex Function
Authors: Sugawa Toshiyuki
Published: March 2021

We consider the inverse function z=g(w)=w+b2w2+⋯ of a normalized convex univalent function w=f(z)=z+a2z2+⋯ on the unit disk in the complex plane. So far, it is known that |bn|≤1 for n=2,3,⋯,8. On the other hand, the inequality |bn|≤1 is not valid for n=10. It is conjectured that |b9|≤1. The present paper offers the estimate |b9|<1.617.
Effect of Heat Treatment on the As-Cast Microstructure and Hardness of NiSi3B2 Alloy
Authors: Gorito Gonçalo M. , Moreira Aida B. , Lacerda Pedro , Vieira Manuel F. , Ribeiro Laura M. M.
Published: March 2021

Cast Ni-Si-B alloys have the potential for high-temperature applications because of their high resistance to wear, impact, corrosion, and oxidation at elevated temperatures due to an appropriate balance of hard phases and austenite that ensures a good compromise between toughness and hardness. In this work, NiSi3B2 specimens, fabricated by the lost-wax casting process, were investigated. Given the complex multiphase cast microstructure, a differential scanning calorimeter (DSC-TGA) analysis was employed to characterize the reactions that occur during solidification and the resulting phases were characterized using scanning electron microscopy (SEM), with energy-dispersive microanalysis (EDS) and backscattered electron (BSE) image and X-ray diffraction (XRD). Due to the presence of hard phases, machining of the Ni-Si-B components can pose additional difficulties. Therefore, the conditions of the solution heat treatment, which might lead to the homogenization of the microstructure, consequently improving its machinability, were also investigated. The results of the heat-treated samples indicated that the dissolution of the eutectic constituent is accompanied by a significant decrease in the hardness (approximately 17%). It is important to emphasize that the solution heat treatments carried out reduced the hardness without affecting the percentage of borides, which will allow improving the machinability without adversely affecting the alloy performance in service.
A Method for Simultaneous Optimization of Blank Shape and Forming Tool Geometry in Sheet Metal Forming Simulations
Authors: Starman Bojan , Cafuta Gašper , Mole Nikolaj
Published: March 2021

This paper presents a numerical method for simultaneous optimization of blank shape and forming tool geometry in three-dimensional sheet metal forming operations. The proposed iterative procedure enables the manufacturing of sheet metal products with geometry fitting within specific tolerances (surface and edge deviations less than 0.5 or 1.0 mm, respectively) that prescribe the maximum allowable deviation between the simulated and desired geometry. Moreover, the edge geometry of the product is affected by the shape of the blank and by an additional trimming phase after the forming process. The influences of sheet metal thinning, edge geometry, and springback after forming and trimming are considered throughout the blank and tool optimization process. It is demonstrated that the procedure effectively optimizes the tool and blank shape within seven iterations without unexpected convergence oscillations. Finally, the procedure thus developed is experimentally validated on an automobile product with elaborated design and geometry which prone to large springback amounts owning to complex-phase advanced high strength steel material selection.
Fatigue Damage of an Asperity in Frictionless Normal Contact with a Rigid Flat
Authors: Chen Zhou , Jiang Yibo , Tong Zheming , Tong Shuiguang
Published: March 2021

Surface fatigue wear widely exists, and it occurs as long as a sufficient number of loading–unloading cycles are applied. Slowing down surface fatigue wear requires understanding the evolution of fatigue damage in the surface. Real surfaces are composed of many asperities; therefore, it is important to study the fatigue damage of a single asperity. A finite element model of an asperity subjected to cyclic elastic–plastic normal loading was developed under frictionless contact condition. The asperity can be either completely or partially unloaded in a loading cycle. For the sake of completeness, both cases were investigated in the present study. The multiaxial Fatemi-Socie fatigue criterion was adopted to evaluate the fatigue damage of the asperity in elastic shakedown state, which was achieved after several loading cycles. For the case of complete unloading, severe fatigue damage was confined in a subsurface ridge starting from the edge of the maximum loaded contact area. The shape and volume of the wear particles were predicted based on a fundamentally valid assumption. For the case of partial unloading, the fatigue damage was much milder. Finally, potential research directions to expand the current study are suggested.
Plant Holobiont Theory: The Phytomicrobiome Plays a Central Role in Evolution and Success
Authors: Lyu Dongmei , Zajonc Jonathan , Pagé Antoine , Tanney Cailun A. S. , Shah Ateeq , Monjezi Nadia , Msimbira Levini A. , Antar Mohammed , Nazari Mahtab , Backer Rachel , Smith Donald L.
Published: March 2021

Under natural conditions, plants are always associated with a well-orchestrated community of microbes—the phytomicrobiome. The nature and degree of microbial effect on the plant host can be positive, neutral, or negative, and depends largely on the environment. The phytomicrobiome is integral for plant growth and function; microbes play a key role in plant nutrient acquisition, biotic and abiotic stress management, physiology regulation through microbe-to-plant signals, and growth regulation via the production of phytohormones. Relationships between the plant and phytomicrobiome members vary in intimacy, ranging from casual associations between roots and the rhizosphere microbial community, to endophytes that live between plant cells, to the endosymbiosis of microbes by the plant cell resulting in mitochondria and chloroplasts. If we consider these key organelles to also be members of the phytomicrobiome, how do we distinguish between the two? If we accept the mitochondria and chloroplasts as both members of the phytomicrobiome and the plant (entrained microbes), the influence of microbes on the evolution of plants becomes so profound that without microbes, the concept of the “plant” is not viable. This paper argues that the holobiont concept should take greater precedence in the plant sciences when referring to a host and its associated microbial community. The inclusivity of this concept accounts for the ambiguous nature of the entrained microbes and the wide range of functions played by the phytomicrobiome in plant holobiont homeostasis.
SARS-CoV-2 N501Y Introductions and Transmissions in Switzerland from Beginning of October 2020 to February 2021—Implementation of Swiss-Wide Diagnostic Screening and Whole Genome Sequencing
Authors: Goncalves Cabecinhas Ana Rita , Roloff Tim , Stange Madlen , Bertelli Claire , Huber Michael , Ramette Alban , Chen Chaoran , Nadeau Sarah , Gerth Yannick , Yerly Sabine , Opota Onya , Pillonel Trestan , Schuster Tobias , Metzger Cesar M. J. A. , Sieber Jonas , Bel Michael , Wohlwend Nadia , Baumann Christian , Koch Michel C. , Bittel Pascal , Leuzinger Karoline , Brunner Myrta , Suter-Riniker Franziska , Berlinger Livia , Søgaard Kirstine K. , Beckmann Christiane , Noppen Christoph , Redondo Maurice , Steffen Ingrid , Seth-Smith Helena M. B. , Mari Alfredo , Lienhard Reto , Risch Martin , Nolte Oliver , Eckerle Isabella , Martinetti Lucchini Gladys , Hodcroft Emma B. , Neher Richard A. , Stadler Tanja , Hirsch Hans H. , Leib Stephen L. , Risch Lorenz , Kaiser Laurent , Trkola Alexandra , Greub Gilbert , Egli Adrian
Published: March 2021

The rapid spread of the SARS-CoV-2 lineages B.1.1.7 (N501Y.V1) throughout the UK, B.1.351 (N501Y.V2) in South Africa, and P.1 (B.1.1.28.1; N501Y.V3) in Brazil has led to the definition of variants of concern (VoCs) and recommendations for lineage specific surveillance. In Switzerland, during the last weeks of December 2020, we established a nationwide screening protocol across multiple laboratories, focusing first on epidemiological and microbiological definitions. In January 2021, we validated and implemented an N501Y-specific PCR to rapidly screen for VoCs, which are then confirmed using amplicon sequencing or whole genome sequencing (WGS). A total of 13,387 VoCs have been identified since the detection of the first Swiss case in October 2020, with 4194 being B.1.1.7, 172 B.1.351, and 7 P.1. The remaining 9014 cases of VoCs have been described without further lineage specification. Overall, all diagnostic centers reported a rapid increase of the percentage of detected VOCs, with a range of 6 to 46% between 25 to 31 of January 2021 increasing towards 41 to 82% between 22 to 28 of February. A total of 739 N501Y positive genomes were analysed and show a broad range of introduction events to Switzerland. In this paper, we describe the nationwide coordination and implementation process across laboratories, public health institutions, and researchers, the first results of our N501Y-specific variant screening, and the phylogenetic analysis of all available WGS data in Switzerland, that together identified the early introduction events and subsequent community spreading of the VoCs.
Comparison of Phenotypical Antimicrobial Resistance between Clinical and Non-Clinical E. coli Isolates from Broilers, Turkeys and Calves in Four European Countries
Authors: Mesa-Varona Octavio , Mader Rodolphe , Velasova Martina , Madec Jean-Yves , Granier Sophie A. , Perrin-Guyomard Agnes , Norstrom Madelaine , Kaspar Heike , Grobbel Mirjam , Jouy Eric , Anjum Muna F. , Tenhagen Bernd-Alois
Published: March 2021

Livestock data on antimicrobial resistance (AMR) are commonly collected from bacterial populations of clinical and non-clinical isolates. In contrast to data on non-clinical isolates from livestock, data on clinical isolates are not harmonized in Europe. The Normalized Resistance Interpretation (NRI) method was applied to overcome the lack of harmonization of laboratory methods and interpretation rules between monitoring systems. Statistical analyses were performed to identify associations between the isolate type (clinical vs. non-clinical) and resistance to four antimicrobials (ampicillin, tetracycline, gentamicin, and nalidixic acid) per animal category in Germany and France. Additional statistical analyses comparing clinical and non-clinical isolates were performed with the available data on the same antimicrobial panel and animal categories from the UK and Norway. Higher resistance prevalence was found in clinical isolates compared to non-clinical isolates from calves to all antimicrobials included in Germany and France. It was also found for gentamicin in broilers from France. In contrast, in broilers and turkeys from Germany and France and in broilers from the UK, a higher resistance level to ampicillin and tetracycline in non-clinical isolates was encountered. This was also found in resistance to gentamicin in isolates from turkeys in Germany. Resistance differed within countries and across years, which was partially in line with differences in antimicrobial use patterns. Differences in AMR between clinical and non-clinical isolates of Escherichia coli are associated with animal category (broiler, calf, and turkey) and specific antimicrobials. The NRI method allowed comparing results of non-harmonized AMR systems and might be useful until international harmonization is achieved.
Mineralogy and Geochemistry (HFSE and REE) of the Present-Day Acid-Sulfate Types Alteration from the Active Hydrothermal System of Furnas Volcano, São Miguel Island, The Azores Archipelago
Authors: Bobos Iuliu , Gomes Celso
Published: March 2021

Acid-sulfate alteration is comprised by clays, sulfate, sinter and native sulphur minerals crystallized as neoformation products from dissolution of primary minerals during water-rock interaction. Smectite, kaolinite, halloysite-7 Å and opal-A occur in assemblages with alunite. Smectite represents a mechanical mixture between two (propylitic and acid-sulfate) alteration types. High amounts of high-field strength elements (HFSE) and rare earth elements (REE) were measured in acid-sulfate rocks. The Nb vs. Ta and Zr vs. Hf show a positive trend and a widely scattered relationships, suggesting a large fractionation during acid-sulfate alteration. Higher ∑REE amounts (up to 934.5 ppm) were found in clay-sulfate assemblages and lower ∑REE amounts in sinter (opal-A ± sulfate, 169.05 ppm) than to fresh rocks (up to 751.2 ppm). The acid-sulfate rocks reveal a distinctive gull-wing chondrite-normalized pattern with a negative Eu anomaly and light- and heavy-REE “wings” similar to the gull-wing pattern of fresh rocks. The Eu/Eu* shows a large fractionation of acid sulfate rocks from 0.16 to 0.78 with respect to fresh trachyte products (0.10 to 0.38). Variation of (La/Sm)N and (La/Yb)N ratio show a large fractionation of light-REE and heavy-REE. The Y vs. Dy and Y vs. Ho show a very good positive correlation coefficient and a large Y fractionation in acid-sulfate rocks with respect to fresh rocks.
Dietary Management of Type 2 Diabetes in the MENA Region: A Review of the Evidence
Authors: Hwalla Nahla , Jaafar Zeinab , Sawaya Sally
Published: March 2021

The alarmingly rising trend of type 2 diabetes constitutes a major global public health challenge particularly in the Middle Eastern and North African (MENA) region where the prevalence is among the highest in the world with a projection to increase by 96% by 2045. The economic boom in the MENA region over the past decades has brought exceptionally rapid shifts in eating habits characterized by divergence from the traditional Mediterranean diet towards a more westernized unhealthy dietary pattern, thought to be leading to the dramatic rises in obesity and non-communicable diseases. Research efforts have brought a greater understanding of the different pathways through which diet and obesity may affect diabetes clinical outcomes, emphasizing the crucial role of dietary interventions and weight loss in the prevention and management of diabetes. The purpose of this review is to explore the mechanistic pathways linking obesity with diabetes and to summarize the most recent evidence on the association of the intake of different macronutrients and food groups with the risk of type 2 diabetes. We also summarize the most recent evidence on the effectiveness of different macronutrient manipulations in the prevention and management of diabetes while highlighting the possible underlying mechanisms of action and latest evidence-based recommendations. We finally discuss the need to adequately integrate dietetic services in diabetes care specific to the MENA region and conclude with recommendations to improve dietetic care for diabetes in the region.
Current Knowledge about Providing Drug–Drug Interaction Services for Patients—A Scoping Review
Authors: Hammar Tora , Hamqvist Sara , Zetterholm My , Jokela Päivi , Ferati Mexhid
Published: March 2021

Drug–drug interactions (DDIs) pose a major problem to patient safety. eHealth solutions have the potential to address this problem and generally improve medication management by providing digital services for health care professionals and patients. Clinical decision support systems (CDSS) to alert physicians or pharmacists about DDIs are common, and there is an extensive body of research about CDSS for professionals. Information about DDIs is commonly requested by patients, but little is known about providing similar support to patients. The aim of this scoping review was to explore and describe current knowledge about providing digital DDI services for patients. Using a broad search strategy and an established framework for scoping reviews, 19 papers were included. The results show that although some patients want to check for DDIs themselves, there are differences between patients, in terms of demands and ability. There are numerous DDI services available, but the existence of large variations regarding service quality implies potential safety issues. The review includes suggestions about design features but also indicates a substantial knowledge gap highlighting the need for further research about how to best design and provide digital DDI to patients without risking patient safety or having other unintended consequences.
A Plant Based Modified Biostimulant (Copper Chlorophyllin), Mediates Defense Response in Arabidopsis thaliana under Salinity Stress
Authors: Islam Md Tariqul , Ckurshumova Wenzi , Fefer Michael , Liu Jun , Uddin Wakar , Rosa Cristina
Published: March 2021

To date, managing salinity stress in agriculture relies heavily on development of salt tolerant plant varieties, a time-consuming process particularly challenging for many crops. Plant based biostimulants (PBs) that enhance plant defenses under stress can potentially address this drawback, as they are not crop specific and are easy to apply in the field. Unfortunately, limited knowledge about their modes of action makes it harder to utilize them on a broader scale. Understanding how PBs enhance plant defenses at cellular and molecular levels, is a prerequisite for the development of sustainable management practices utilizing biostimulants to improve crop health. In this study we elucidated the protective mechanism of copper chlorophyllin (Cu-chl), a PB, under salinity stress. Our results indicate that Cu-chl exerts protective effects primarily by decreasing oxidative stress through modulating cellular H2O2 levels. Cu-chl treated plants increased tolerance to oxidative stress imposed by an herbicide, methyl viologen dichloride hydrate as well, suggesting a protective role against various sources of reactive oxygen species (ROS). RNA-Seq analysis of Cu-chl treated Arabidopsis thaliana seedlings subjected to salt stress identified genes involved in ROS detoxification, and cellular growth.
Distribution of Orchids with Different Rooting Systems in the Czech Republic
Authors: Štípková Zuzana , Tsiftsis Spyros , Kindlmann Pavel
Published: March 2021

Understanding diversity patterns along altitudinal gradients and the effect of global change on abundance, distribution patterns and species survival are of the most discussed topics in biodiversity research. Here, we determined the associations of orchid species richness and the degree of their specialization to specific environmental conditions (expressed by species specialization index) with altitude in six floristic areas in the Czech Republic. We distinguished three basic trends in these relationships: linear, parabolic and cubic. We then determined whether these trends differ between three orchid groups classified by their rooting systems: rhizomatous, intermediate and tuberous. We used distributional data on 69 species and subspecies of terrestrial orchids recorded in the Czech Republic and interpolated them at 100-m intervals along an altitudinal gradient in each floristic area. The trends in both species richness and mean species specialization index differed between the six floristic areas within each of the three orchid groups studied. These patterns are probably strongly influenced by the orography of the country and the distribution of different habitats in the six floristic areas in the Czech Republic. We also found that the most widely distributed orchid group in the Czech Republic are the rhizomatous orchids, followed by intermediate and tuberous ones.
Towards Using Police Officers’ Business Smartphones for Contactless Fingerprint Acquisition and Enabling Fingerprint Comparison against Contact-Based Datasets
Authors: Kauba Christof , Söllinger Dominik , Kirchgasser Simon , Weissenfeld Axel , Fernández Domínguez Gustavo , Strobl Bernhard , Uhl Andreas
Published: March 2021

Recent developments enable biometric recognition systems to be available as mobile solutions or to be even integrated into modern smartphone devices. Thus, smartphone devices can be used as mobile fingerprint image acquisition devices, and it has become feasible to process fingerprints on these devices, which helps police authorities carry out identity verification. In this paper, we provide a comprehensive and in-depth engineering study on the different stages of the fingerprint recognition toolchain. The insights gained throughout this study serve as guidance for future work towards developing a contactless mobile fingerprint solution based on the iPhone 11, working without any additional hardware. The targeted solution will be capable of acquiring 4 fingers at once (except the thumb) in a contactless manner, automatically segmenting the fingertips, pre-processing them (including a specific enhancement), and thus enabling fingerprint comparison against contact-based datasets. For fingertip detection and segmentation, various traditional handcrafted feature-based approaches as well as deep-learning-based ones are investigated. Furthermore, a run-time analysis and first results on the biometric recognition performance are included.
Proposed ANFIS Based Approach for Fault Tracking, Detection, Clearing and Rearrangement for Photovoltaic System
Authors: Bendary Ahmed F. , Abdelaziz Almoataz Y. , Ismail Mohamed M. , Mahmoud Karar , Lehtonen Matti , Darwish Mohamed M. F.
Published: March 2021

In the last few decades, photovoltaics have contributed deeply to electric power networks due to their economic and technical benefits. Typically, photovoltaic systems are widely used and implemented in many fields like electric vehicles, homes, and satellites. One of the biggest problems that face the relatability and stability of the electrical power system is the loss of one of the photovoltaic modules. In other words, fault detection methods designed for photovoltaic systems are required to not only diagnose but also clear such undesirable faults to improve the reliability and efficiency of solar farms. Accordingly, the loss of any module leads to a decrease in the efficiency of the overall system. To avoid this issue, this paper proposes an optimum solution for fault finding, tracking, and clearing in an effective manner. Specifically, this proposed approach is done by developing one of the most promising techniques of artificial intelligence called the adaptive neuro-fuzzy inference system. The proposed fault detection approach is based on associating the actual measured values of current and voltage with respect to the trained historical values for this parameter while considering the ambient changes in conditions including irradiation and temperature. Two adaptive neuro-fuzzy inference system-based controllers are proposed: (1) the first one is utilized to detect the faulted string and (2) the other one is utilized for detecting the exact faulted group in the photovoltaic array. The utilized model was installed using a configuration of 4 × 4 photovoltaic arrays that are connected through several switches, besides four ammeters and four voltmeters. This study is implemented using MATLAB/Simulink and the simulation results are presented to show the validity of the proposed technique. The simulation results demonstrate the innovation of this study while proving the effective and high performance of the proposed adaptive neuro-fuzzy inference system-based approach in fault tracking, detection, clearing, and rearrangement for practical photovoltaic systems.
High-Precision Automatic Calibration Modeling of Point Light Source Tracking Systems
Authors: Li Ruijin , Zhang Liming , Wang Xianhua , Xu Weiwei , Li Xin , Li Jiawei , Hu Chunhui
Published: March 2021

To realize high-precision and high-frequency unattended site calibration and detection of satellites, automatic direction adjustment must be implemented in mirror arrays. This paper proposes a high-precision automatic calibration model based on a novel point light source tracking system for mirror arrays. A camera automatically observes the solar vector, and an observation equation coupling the image space and local coordinate systems is established. High-precision calibration of the system is realized through geometric error calculation of multipoint observation data. Moreover, model error analysis and solar tracking verification experiments are conducted. The standard deviations of the pitch angle and azimuth angle errors are 0.0176° and 0.0305°, respectively. The root mean square errors of the image centroid contrast are 2.0995 and 0.8689 pixels along the x- and y-axes, respectively. The corresponding pixel angular resolution errors are 0.0377° and 0.0144°, and the comprehensive angle resolution error is 0.0403°. The calculated model values are consistent with the measured data, validating the model. The proposed point light source tracking system can satisfy the requirements of high-resolution, high-precision, high-frequency on-orbit satellite radiometric calibration and modulation transfer function detection.
Framework for the Development of Affective and Smart Manufacturing Systems Using Sensorised Surrogate Models
Authors: Ávila-Gutiérrez María Jesús , Aguayo-González Francisco , Lama-Ruiz Juan Ramón
Published: March 2021

Human Factor strategy and management have been affected by the incorporation of Key Enabling Technologies (KETs) of industry 4.0, whereby operator 4.0 has been configured to address the wide variety of cooperative activities and to support skills that operate in VUCA (volatile, uncertain, complex, and ambiguous) environments under the interaction with ubiquitous interfaces on real and virtual hybrid environments of cyber-physical systems. Current human Competences-Capacities that are supported by the technological enablers could result in a radically disempowered human factor. This means that in the processes of optimization and improvement of manufacturing systems from industry 4.0 to industry 5.0, it would be necessary to establish strategies for the empowerment of the human factor, which constitute symbiotic and co-evolutionary socio-technical systems through talent, sustainability, and innovation. This paper establishes a new framework for the design and development of occupational environments 5.0 for the inclusion of singularized operators 4.0, such as individuals with special capacities and talents. A case study for workers and their inclusion in employment is proposed. This model integrates intelligent and inclusive digital solutions in the current workspaces of organizations under digital transformation.
Manipulation Planning for Object Re-Orientation Based on Semantic Segmentation Keypoint Detection
Authors: Wong Ching-Chang , Yeh Li-Yu , Liu Chih-Cheng , Tsai Chi-Yi , Aoyama Hisasuki
Published: March 2021

In this paper, a manipulation planning method for object re-orientation based on semantic segmentation keypoint detection is proposed for robot manipulator which is able to detect and re-orientate the randomly placed objects to a specified position and pose. There are two main parts: (1) 3D keypoint detection system; and (2) manipulation planning system for object re-orientation. In the 3D keypoint detection system, an RGB-D camera is used to obtain the information of the environment and can generate 3D keypoints of the target object as inputs to represent its corresponding position and pose. This process simplifies the 3D model representation so that the manipulation planning for object re-orientation can be executed in a category-level manner by adding various training data of the object in the training phase. In addition, 3D suction points in both the object’s current and expected poses are also generated as the inputs of the next operation stage. During the next stage, Mask Region-Convolutional Neural Network (Mask R-CNN) algorithm is used for preliminary object detection and object image. The highest confidence index image is selected as the input of the semantic segmentation system in order to classify each pixel in the picture for the corresponding pack unit of the object. In addition, after using a convolutional neural network for semantic segmentation, the Conditional Random Fields (CRFs) method is used to perform several iterations to obtain a more accurate result of object recognition. When the target object is segmented into the pack units of image process, the center position of each pack unit can be obtained. Then, a normal vector of each pack unit’s center points is generated by the depth image information and pose of the object, which can be obtained by connecting the center points of each pack unit. In the manipulation planning system for object re-orientation, the pose of the object and the normal vector of each pack unit are first converted into the working coordinate system of the robot manipulator. Then, according to the current and expected pose of the object, the spherical linear interpolation (Slerp) algorithm is used to generate a series of movements in the workspace for object re-orientation on the robot manipulator. In addition, the pose of the object is adjusted on the z-axis of the object’s geodetic coordinate system based on the image features on the surface of the object, so that the pose of the placed object can approach the desired pose. Finally, a robot manipulator and a vacuum suction cup made by the laboratory are used to verify that the proposed system can indeed complete the planned task of object re-orientation.
Applications of Big Data Analytics to Control COVID-19 Pandemic
Authors: Alsunaidi Shikah J. , Almuhaideb Abdullah M. , Ibrahim Nehad M. , Shaikh Fatema S. , Alqudaihi Kawther S. , Alhaidari Fahd A. , Khan Irfan Ullah , Aslam Nida , Alshahrani Mohammed S.
Published: March 2021

The COVID-19 epidemic has caused a large number of human losses and havoc in the economic, social, societal, and health systems around the world. Controlling such epidemic requires understanding its characteristics and behavior, which can be identified by collecting and analyzing the related big data. Big data analytics tools play a vital role in building knowledge required in making decisions and precautionary measures. However, due to the vast amount of data available on COVID-19 from various sources, there is a need to review the roles of big data analysis in controlling the spread of COVID-19, presenting the main challenges and directions of COVID-19 data analysis, as well as providing a framework on the related existing applications and studies to facilitate future research on COVID-19 analysis. Therefore, in this paper, we conduct a literature review to highlight the contributions of several studies in the domain of COVID-19-based big data analysis. The study presents as a taxonomy several applications used to manage and control the pandemic. Moreover, this study discusses several challenges encountered when analyzing COVID-19 data. The findings of this paper suggest valuable future directions to be considered for further research and applications.
Snapshot Imaging Spectrometer Based on Pixel-Level Filter Array (PFA)
Authors: Xie Yunqiang , Liu Chunyu , Liu Shuai , Song Weiyang , Fan Xinghao
Published: March 2021

Snapshot spectral imaging technology plays an important role in many fields. However, most existing snapshot imaging spectrometers have the shortcomings of a large volume or heavy computational burden. In this paper, we present a novel snapshot imaging spectrometer based on the pixel-level filter array (PFA), which can simultaneously obtain both spectral and spatial information. The system is composed of a fore-optics, a PFA, a relay lens, and a monochromatic sensor. The incoming light first forms an intermediate image on the PFA through the fore-optics. Then, the relay lens reimages the spectral images on the PFA onto the monochromatic sensor. Through the use of the PFA, we can capture a three-dimensional (spatial coordinates and wavelength) datacube in a single exposure. Compared with existing technologies, our system possesses the advantages of a simple implementation, low cost, compact structure, and high energy efficiency by removing stacked dispersive or interferometric elements. Moreover, the characteristic of the direct imaging mode ensures the low computational burden of the system, thus shortening the imaging time. The principle and design of the system are described in detail. An experimental prototype is built and field experiments are carried out to verify the feasibility of the proposed scheme.
Radicalisation, Foreign Fighters and the Ukraine Conflict: A Playground for the Far-Right?
Authors: MacKenzie Alex , Kaunert Christian
Published: March 2021

Ukraine has been viewed by some as having become a training ground, networking opportunity, and general hub for the far-right due to the conflict in the east of the country, which began in 2014. With this type of terrorism on the rise in the West and events like the storming of the US Capitol Building in January 2021 fresh in the memory, it should come as no surprise that any such possibilities will generate concern. To investigate the types and extent of the threats posed by participants in the Ukraine conflict, we scrutinise the activities of a few alumni that we know of to date, as well as highlighting neglected historical episodes of right-wing fighters. We make three arguments here based on occurrences so far. Firstly, we know little about far-right foreign fighters and more attention needs to be paid to historical instances of the phenomenon. Secondly, some limited but diverse threats have already arisen from the Ukraine conflict and others may emerge in the future, but it would be unwise to overplay and homogenise the problem. Finally, it is Ukraine itself that probably faces the greatest challenges from its domestic far-right, although, if left unchecked, it may affect others in providing a space for, and permitting the growth of, connections with like-minded individuals and groups based elsewhere. Despite our warning about exaggerating the problem, Western security services should be taking the far-right very seriously at present, such as in relation to potential infiltration of them by such elements.
Being a Group Fitness Instructor during the COVID-19 Crisis: Navigating Professional Identity, Social Distancing, and Community
Authors: Andersson Karin , Andreasson Jesper
Published: March 2021

Research question and purpose: Les Mills is a New Zealand-based fitness distributor with a community consisting of approximately 140.000 instructors worldwide who teach standardized workout routines. This paper aims to explore how the COVID-19 pandemic and related measurements, such as social distancing affect the everyday lives and professions of Les Mills International (LMI) group fitness instructors. The aim was met with the following research questions: RQ1: How are social distancing and social connectedness understood, and how do they condition LMI instructors’ understanding of their profession? RQ2: What do LMI instructors think about the #LesMillsUnited campaign to maintain a strong trainer community in the midst of the pandemic? RQ3: How do LMI instructors think that group fitness will change long term due to social distancing? Research methods: Using qualitative measures and a case-study-based approach, data were gathered through interviews with LMI-certified group fitness instructors. Seven semi-structured focused group discussions with fifteen group fitness instructors from different countries were conducted and audio recorded. The first round of virtual discussions took place in April 2020, and the follow-up talks in September 2020. A thematic analysis was employed to analyze the material. Results and findings: According to the participants, online classes as a means of upholding group fitness in times of social distancing is an insufficient substitute to face-to-face instructing, lacking social connectedness that is normally maintained through successful rituals or social scripts. Navigating “instructorhood” during the pandemic includes emotional labor where not only relationships to clients are challenged, but instructors also experience societal pressure to reinvent themselves as instructors. Implications: With no way of telling how long social distancing needs to be practiced, the group fitness industry is facing unprecedented challenges. Making sense of the group fitness profession currently preoccupies instructors who may now have to redefine to themselves how they can teach, and who for.
Transformations for FIR and IIR Filters’ Design
Authors: Stavrou V. N. , Tsoulos I. G. , Mastorakis Nikos E.
Published: March 2021

In this paper, the transfer functions related to one-dimensional (1-D) and two-dimensional (2-D) filters have been theoretically and numerically investigated. The finite impulse response (FIR), as well as the infinite impulse response (IIR) are the main 2-D filters which have been investigated. More specifically, methods like the Windows method, the bilinear transformation method, the design of 2-D filters from appropriate 1-D functions and the design of 2-D filters using optimization techniques have been presented.
The Potential Role of Nonhuman Primate Models to Better Comprehend Early Life Immunity and Maternal Antibody Transfer
Authors: Sartoretti Julie , Eberhardt Christiane S.
Published: March 2021

Early life immunity is a complex field of research and there are still gaps in knowledge regarding the detailed mechanism of maternal antibody transfer, the impact of maternal antibodies on infant vaccine responses and the ontogeny of human early life immunity. A comprehensive understanding is necessary to identify requirements for early life vaccines and to improve early childhood immunization. New immunological methods have facilitated performing research in the youngest, however, some questions can only be addressed in animal models. To date, mostly murine models are used to study neonatal and infant immunity since they are well-described, easy to use and cost effective. Given their limitations especially in the transfer biology of maternal antibodies and the lack of infectivity of numerous human pathogens, this opinion piece discusses the potential and prerequisites of the nonhuman primate model in studying early life immunity and maternal antibody transfer.
Soluble Spike DNA Vaccine Provides Long-Term Protective Immunity against SARS-CoV-2 in Mice and Nonhuman Primates
Authors: Seo Yong Bok , Suh You Suk , Ryu Ji In , Jang Hwanhee , Oh Hanseul , Koo Bon-Sang , Seo Sang-Hwan , Hong Jung Joo , Song Manki , Kim Sung-Joo , Sung Young Chul
Published: March 2021

The unprecedented and rapid spread of SARS-CoV-2 (severe acute respiratory syndrome-coronavirus-2) has motivated the need for a rapidly producible and scalable vaccine. Here, we developed a synthetic soluble SARS-CoV-2 spike (S) DNA-based vaccine candidate, GX-19. In mice, immunization with GX-19 elicited not only S-specific systemic and pulmonary antibody responses but also Th1-biased T cell responses in a dose-dependent manner. GX-19-vaccinated nonhuman primates seroconverted rapidly and exhibited a detectable neutralizing antibody response as well as multifunctional CD4+ and CD8+ T cell responses. Notably, when the immunized nonhuman primates were challenged at 10 weeks after the last vaccination with GX-19, they had reduced viral loads in contrast to non-vaccinated primates as a control. These findings indicate that GX-19 vaccination provides a durable protective immune response and also support further development of GX-19 as a vaccine candidate for SARS-CoV-2.
Progression from Type 2 Macular Neovascularization to Fibrovascular Pigment Epithelial Detachment
Authors: LE Hoang Mai , Mimoun Gérard , Cohen Salomon Y. , Jung Camille , Semoun Oudy , Souied Eric H.
Published: March 2021

The aim of this study was to report unusual progression of type 2 macular neovascularization (MNV) associated with age-related macular degeneration (AMD), high myopia or angioid streaks. Retrospective multicentric observational case series data were used. Eyes that progressed from type 2 MNV secondary to AMD, high myopia or angioid streaks to fibrovascular pigment epithelial detachment (PED) were included. A total of 29 treatment-naive eyes from 29 patients with type 2 MNV secondary to AMD (n = 14), high myopia (n = 10) or angioid streaks (n = 5) that progressed to a fibrovascular PED on Spectral Domain-Optical Coherence Tomography were used. This progression occurred within 3 months after anti-VEGF therapy initiation. Logarithm of minimum angle of resolution (LogMAR) visual acuity improved significantly after anti-VEGF therapy, from 0.55 (SD ± 0.30) (20/63–20/80) at baseline to 0.30 (20/40) at 3 months, and 0.33 (20/40) at the final follow-up (mean follow up: 3.68 years). Mean number of intravitreal injections per year for patients with a total follow-up ≥ 12 months (n = 24) was 4.3 ± 2.1 per year. Progression from type 2 MNV to a fibrovascular PED may occur in patients suffering from AMD, high myopia or angioid streaks. This progression appears early after initiation of anti-VEGF therapy and is associated with a favorable visual and anatomical outcome, at least on a short follow up basis.
Magnetic Gears and Magnetically Geared Machines with Reduced Rare-Earth Elements for Vehicle Applications
Authors: Al-Qarni Ali , EL-Refaie Ayman
Published: March 2021

This paper covers a new emerging class of electrical machines, namely, Magnetic Gears (MGs) and Magnetically Geared Machines (MGMs). This particular kind of gears/machines is capable of either scaling up or down the revolutions-per-minute to meet various load profiles as in the case of mechanical gearboxes, but with physical isolation between the rotating components. This physical isolation between the rotational components leads to several advantages in favor of MGs and MGMs over mechanical gearboxes. Although MGs and MGMs can potentially provide a solution for some of the practical issues of mechanical gears, MGs and MGMs have two major challenges that researchers have been trying to address. Those challenges are the high usage of rare-earth Permanent Magnet (PM) materials and the relatively complex mechanical structure of MGs and MGMs, both of which are a consequence of the multi-airgap design. This paper presents designs that reduce the PM rare-earth content for Electric Vehicles (EVs). Additionally, the paper will ensure having practical designs that do not run the risk of permanent demagnetization. The paper will also discuss some new designs to simplify the mechanical structure.
World trends in agricultural engineering and the direction of technical and technological modernization of crop production in the republic of Belarus
Authors: Kovalev I.L.
Published: March 2021

Some basic directions in the global development of agricultural machinery and global trends in the digital transformation of agriculture are reviewed and identified based on analysis of reports and articles by well-known expert organizations in this field. The analysis of the technical re-equipment of the Belarusian crop production over the past decade has been carried out, the directions of digitalization of agricultural production of the republic identified by the current State programs in the agricultural sector and Decree of the President of the Republic of Belarus No. 8 “On the Development of the Digital Economy” have been determined.
VIRTUAL UNIVERSITY: EDUCATION AS A LIFESTYLE
Authors: Svyrydenko Denys , Kyvliuk Valentyna
Published: March 2021

The concept of the virtual university is relatively new and it is necessary to distinguish a number of contradictory points in its verification. Firstly, it is the quality of the education received. The problem of educational process content at the virtual university, organization of control and level of accomplished tasks, issues of intellectual abilities and critical thinking development, reflexivity of consciousness are the subject of heated discussions of both the supporters and opponents of the virtual university idea. Secondly, there is the question of the way of thinking. The virtual space involves a network mode of organization characterized by openness of the structure, poly variability of determination and expediency of modal logic. The phenomenon of virtual university is the result of responding to the needs of social transformation. In such model, the content of the social roles of the teacher and the student changes significantly. The competence of the modern teacher is not limited to knowledge. After all, the most experienced academician is not able to absorb all the information in a certain science, and obviously loses in the volume of assimilated information to any search engine.
Precision livestock farming technologies: Novel direction of information flow
Authors: TEKİN Koray , YURDAKÖK DİKMEN Begüm , KANCA Halit , GUATTEO Raphael
Published: March 2021

Precision livestock farming (PLF) is a digital management system that continuously measures the production, reproduction, health and welfare of animals and environmental impacts of the herd by using information and communication technologies (ICT) and controls all stages of the production process. In conventional livestock management, decisions are mostly based on the appraisal, judgment, and experience of the farmer, veterinarian, and workers. The increasing demand for production and the number of animals makes it difficult for humans to keep track of animals. It is clear that a person is not able to continuously watch the animals 24 hours a day to receive reliable audio-visual data for management. Recent technologies already changed the information flow from animal to human, which helps people to collect reliable information and transform it into an operational decision-making process (eg reproduction management or calving surveillance). Today, livestock farming must combine requirements for a transparent food supply chain, animal welfare, health, and ethics as a traceable-sustainable model by obtaining and processing reliable data using novel technologies. This review provides preliminary information on the advances in ICT for livestock management.