bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analog signal processing through space-time digital metasurfaces
Authors: Rajabalipanah Hamid , Abdolali Ali , Iqbal Shahid , Zhang Lei , Cui Tie Jun 
Published: March 2021

Abstract
In the quest to realize analog signal processing using subwavelength metasurfaces, in this paper, we present the first demonstration of programmable time-modulated metasurface processors based on the key properties of spatial Fourier transformation. Exploiting space-time coding strategy enables local, independent, and real-time engineering of not only amplitude but also phase profile of the contributing reflective digital meta-atoms at both central and harmonic frequencies. Several illustrative examples are demonstrated to show that the proposed multifunctional calculus metasurface is capable of implementing a large class of useful mathematical operators, including 1st- and 2nd-order spatial differentiation, 1st-order spatial integration, and integro-differential equation solving accompanied by frequency conversions. Unlike the recent proposals based on the Green’s function (GF) method, the designed time-modulated signal processor effectively operates for input signals containing wide spatial frequency bandwidths with an acceptable gain level. Proof-of-principle simulations are also reported to demonstrate the successful realization of image processing functions like edge detection. This time-varying wave-based computing system can set the direction for future developments of programmable metasurfaces with highly promising applications in ultrafast equation solving, real-time and continuous signal processing, and imaging.
Metallographic Preparation of Single Powder Particles
Authors: Milkereit B. , Meißner Y. , Ladewig C. , Osten J. , Peng Q. , Yang B. , Springer A. , Keßler O. 
Published: March 2021

Abstract
This work developed a systematic method for a metallographic preparation of single powder particles with diameters of approx. 20 to 40 μm. It was motivated by the objective of understanding additive manufacturing processes such as Laser Powder Bed Fusion. A fundamental aspect of the relationship between manufacturing, structure, and properties is the correlation of rapid solidification and resulting microstructure. During powder-based additive manufacturing processes, cooling rates up to 1 MK/s are attained. A thermal analysis determining the characteristics of solidification at such rapid cooling rates can be performed with the aid of chip sensor-based, dynamic Differential Fast Scanning Calorimetry, DFSC. For this purpose, the heat flow during the solidification of single powder particles is measured and, for instance, the solidification onset temperature is evaluated as a function of cooling rate. It is thus possible to estimate the undercooling which has a significant impact on the resulting structure. Subsequently, cross sections of single powder particles must be prepared for the analysis of the resulting structure.
Biochar caged zirconium ferrite nanocomposites for the adsorptive removal of Reactive Blue 19 dye in a batch and column reactors and conditions optimizaton
Authors: Perveen Shazia , Nadeem Raziya , Ali Shaukat , Jamil Yasir 
Published: March 2021

Abstract
Biochar caged zirconium ferrite (BC-ZrFe2O5) nanocomposites were fabricated and their adsorption capacity for Reactive Blue 19 (RB19) dye was evaluated in a fixed-bed column and batch sorption mode. The adsorption of dye onto BC-ZrFe2O5 NCs followed pseudo-second-order kinetics (R
2 = 0.998) and among isotherms, the experimental data was best fitted to Sips model as compared to Freundlich and Langmuir isotherms models. The influence of flow-rate (3–5 mL min−1), inlet RB19 dye concentration (20–100 mg L−1) and quantity of BC-ZrFe2O5 NCs (0.5–1.5 g) on fixed-bed sorption was elucidated by Box-Behnken experimental design. The saturation times (C

t
/C

o
= 0.95) and breakthrough (C

t
/C

o
= 0.05) were higher at lower flow-rates and higher dose of BC-ZrFe2O5 NCs. The saturation times decreased, but breakthrough was increased with the initial RB19 dye concentration. The treated volume was higher at low sorbent dose and influent concentration. Fractional bed utilization (FBU) increased with RB19 dye concentration and flow rates at low dose of BC-ZrFe2O5 NCs. Yan model was fitted best to breakthrough curves data as compared to Bohart-Adams and Thomas models. Results revealed that BC-ZrFe2O5 nanocomposite has promising adsorption efficiency and could be used for the adsorption of dyes from textile effluents.
Autonomisierung von Shopfloor Management
Authors: Bock Tobias , Höfer Stephan 
Published: March 2021

Abstract
Neue Technologien der Digitalisierung, Vernetzung und künstlichen Intelligenz werden zunehmend auch im Shopfloor Management (SFM) Einzug halten. Dieser Beitrag beschreibt in vier Stufen, wie sich das klassische SFM über das digitale SFM hin zu einem smarten und autonomen SFM entwickeln könnte. Darauf aufbauend wird diskutiert, welche Auswirkungen der Einsatz dieser neuen Technologien auf die operative Gestaltung der Durchführung eines SFM hätte und welche Konsequenzen somit auf Mitarbeiter und Führungskräfte zukommen würden.*)
Anwendungen aktiver Traceability-Systeme
Authors: Urnauer Christian , Schreiber Markus , Bausch Phillip , Metternich Joachim 
Published: March 2021

Abstract
Mithilfe aktiver Traceability wird durch die Verknüpfung von Maschinen-, Prozess- und Produktdaten die Transparenz über Produktionsprozesse gesteigert. Anhand der Umsetzungen im Transferprojekt ArePron wird in diesem Beitrag beispielhaft aufgezeigt, welche konkreten Industrieanwendungen sich durch die Nutzung dieser Traceability-Daten realisieren lassen. Dabei werden Anwendungen aus den Bereichen Kundendienstleistung, Echtzeitabbild von Leistungskennzahlen, Dynamische Prozesssteuerung, Prozessanalyse sowie Lagermanagement betrachtet.**)
Digitales Bauzustandsmonitoring im Schiffbau
Authors: Sender Jan , Geist Michael , Fischer Anne , Flügge Wilko 
Published: March 2021

Abstract
Schiffbauprojekte müssen trotz steigendem Arbeitsumfang in immer kürzeren Lieferzeiten fertiggestellt werden. Daher haben sich komplexe maritime Wertschöpfungsketten gebildet, die ein hohes Maß an Arbeitsteilung praktizieren. Während eines Schiffbauprojektes müssen viele Arbeiten und Akteure zeitlich und inhaltlich koordiniert werden. Die Kommunikation des Bauzustandes entlang der Wertschöpfungskette spielt eine entscheidende Rolle. Dieser Beitrag präsentiert einen Ansatz, wie durch geeignete Digitalisierung das Bauzustandsmonitoring im Schiffbau optimiert werden kann.
The Concept of Pesticide-Free Pest Control in the Crimean Forests
Authors: Ivashov Anatoliy , Simchuk Andriy 
Published: March 2021

Oak leafroller, gypsy and winter moths contribute to a pathological situation in the Crimean forests exposed to strong recreational activities, which add to the weakening of the forest ecosystems. In this respect we develop a concept of pesticide-free forest protection that presupposes an optimal balance between natural self-regulation opportunities and management, taking into account the long-term effects. The practical steps include preventive and current biological pest control, different in primary, secondary and tertiary niduses of pest outbreaks in the Crimean forests. All pest-control measures should be elaborated as a successive chain of steps joining in a common ecologically and economically sound system. Preventive and current bio-control actions become easy and soft with increase in the forest’s ecosystem complexity and restoration of natural self-regulation.
Subthreshold membrane potential dynamics of posterior parietal cortical neurons coupled with hippocampal ripples
Authors: Sato Y. , Mizuno H. , Matsumoto N. , Ikegaya Y. 
Published: March 2021

AbstractDuring behavioral states of immobility, sleep, and anesthesia, the hippocampus generates high-frequency oscillations called ripples. Ripples occur simultaneously with synchronous neuronal activity in the neocortex, known as slow waves, and contribute to memory consolidation. During these ripples, various neocortical regions exhibit modulations in spike rates and local field activity irrespective of whether they receive direct synaptic inputs from the hippocampus. However, little is known about the subthreshold dynamics of the membrane potentials of neocortical neurons during ripples. We patch-clamped layer 2/3 pyramidal cells in the posterior parietal cortex (PPC), a neocortical region that is involved in allocentric spatial representation of behavioral exploration and sequential series of relevant action potentials during ripples. We simultaneously monitored the membrane potentials of post hoc-identified PPC neurons and the local field potentials of the hippocampus in anesthetized mice. More than 50% of the recorded PPC neurons exhibited significant depolarizations and/or hyperpolarizations during ripples. Histological inspections of the recorded neurons revealed that the ripple-modulated PPC neurons were distributed in the PPC in a spatially non-biased fashion. These results suggest that hippocampal ripples are widely but selectively associated with the subthreshold dynamics of the membrane potentials of PPC neurons even though there is no monosynaptic connectivity between the hippocampus and the PPC.
Agreement between heart rate deflection point and maximal lactate steady state in young adults with different body masses
Authors: Afroundeh R. , Hofmann P. , Esmaeilzadeh S. , Narimani M. , Pesola A.J. 
Published: March 2021

AbstractWe examined the agreement between heart rate deflection point (HRDP) variables with maximal lactate steady state (MLSS) in a sample of young males categorized to different body mass statuses using body mass index (BMI) cut-off points. One hundred and eighteen young males (19.9 ± 4.4 years) underwent a standard running incremental protocol with individualized speed increment between 0.3 and 1.0 km/h for HRDP determination. HRDP was determined using the modified Dmax method called S.Dmax. MLSS was determined using 2-5 series of constant-speed treadmill runs. Heart rate (HR) and blood lactate concentration (La) were measured in all tests. MLSS was defined as the maximal running speed yielding a La increase of less than 1 mmol/L during the last 20 min. Good agreement was observed between HRDP and MLSS for HR for all participants (±1.96; 95% CI = −11.5 to +9.2 b/min, ICC = 0.88; P < 0.001). Good agreement was observed between HRDP and MLSS for speed for all participants (±1.96; 95% CI = −0.40 to +0.42 km/h, ICC = 0.98; P < 0.001). The same findings were observed when participants were categorized in different body mass groups. In conclusion, HRDP can be used as a simple, non-invasive and time-efficient method to objectively determine submaximal aerobic performance in nonathletic young adult men with varying body mass status, according to the chosen standards for HRDP determination.
Challenges of a mature Russian field's redevelopment – Advantages and disadvantages of quick-look geologic modeling
Authors: Nemes István , Sebők Szilvia Szilágyi , Csató István 
Published: March 2021

AbstractDue to the global oil price crisis in 2014, one of the MOL's preventive/reactive measures was to identify geologically or commercially risky elements within their portfolio. This involved reevaluation of all geologic data from Field A in the Volga-Urals Basin. In re-evaluating Field A, several unexpected challenges, problems and pitfalls were faced by the interdisciplinary team performing the task of building a new database, quality checking, and interpreting data dating back to 1947. To overcome these challenges related to this mature field, new approaches and fit-for-purpose methods were required in order to achieve the overall goal of obtaining a reliable estimation of remaining hydrocarbon potential. In the first phase a first-pass 3D geologic model was constructed, along with wrangling, cleaning and interpreting 70 years of subsurface data. This paper focuses on the main challenges involved in evaluating or reevaluating reservoir aspects of a mature field.The primary challenges were related to the estimation of remaining in-place hydrocarbon volumes, the optimization of infill well placement, the identification of primary and secondary well targets, the identification of critical data gaps, and the planning of new data acquisitions. The hands-on experience gained during the development of the geologic model provided invaluable information for the next steps needed in the redevelopment of the field.
Prediction and numerical simulation of residual stress in multi-pass pipe welds
Authors: Hasan Al-Hafadhi Mahmood , Krallics Gyorgy 
Published: March 2021

AbstractA numerical simulation procedure is presented to predict residual stress states in multi-pass welds in oil transportation pipes. In this paper, a two-dimensional thermo-mechanical finite element model is used to calculate the temperature distribution, hardness, and the distribution of residual stresses during multi-pass welding of pipes of dissimilar metals and varying thicknesses. In this model, the temperature dependence of the thermal and mechanical properties of the material was considered. The present model was validated using the hardness measurement. Good agreement was found between the measurement and the numerical simulation results. The simulated result shows that the two-dimensional model can be effectively used to simulate the hardness test and predict the residual stress in the pipe weld. The simulation results and measurements suggest that the model with moving heat source can obtain a good prediction of residual welding stress. Both the two-dimensional and the three-dimensional modeling can be used to estimate the residual stresses in different weld regions and help saving time.
In-vitro evaluation of antioxidant and antiradical potential of successive extracts, semi-purified fractions and biosynthesized silver nanoparticles of Rumex vesicarius
Authors: YOUNES Kareem M. , ROMEILAH Ramy M. , EL-BELTAGI Hossam S. , EL MOLL Hani , RAJENDRASOZHAN Saravanan , EL-SHEMY Hany A. , SHALABY Emad A. 
Published: March 2021

The aim of the present study was to assess in vitro the antiradical and antioxidant activities of successive extracts and semi-purified fractions from Rumex vesicarius L. In the present work, three extracts (n-Hexane, ethyl acetate and methanol) and 22 column fractions of methanolic extract (as promising extract) were evaluated against 2,2-diphenyl- 1-picrylhydrazyl (DPPH•) and 2,2-azinobis (3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) radical scavenging methods as antiradical and antioxidant activities compared with Butylated hydroxytoluene (BHT) as synthetic standard and silver nanoparticles of methanolic extract (Ag-NPs-Me), in addition to analysis of chemical constituents of extract and fraction using Gas chromatography–mass spectrometry (GC-MS). The obtained results revealed that, both methods go parallel showing that the concentration of extract and incubation time are dependent and proportional with phenolic compounds concentration. Absolute methanol extract recorded the highest antioxidant activity when compared with the other crude extracts with 79.3 and 78.8% against DPPH and ABTS respectively when compared with BHT as synthetic standard (89.4 and 89.9%) against DPPH and ABTS respectively. Calculation of the antiradical activity units showed the highest values of methanolic extract and its promising fraction (No. 12) after 300 seconds (5 minutes) comparing with antioxidant activity (30 min). Also, the antioxidant activity increased with synthetic Ag-NPs-Me when compared with methanolic extract by (IC50= 53.9 and 74.6 µg/ml respectively). Thus, the GC-MS analysis of successive extracts of R. vesicarius L showed a highly complex profile, containing approximately 24 different components. One pure compound was identified from fraction No. 12. The identified compound was l-(+)- ascorbic acid 2, 6-dihexadecanoate. The data also revealed presence of closely similar antioxidant activities in methanolic extract or its pure compounds with BHT when mixed at different proportions. From the obtained results it could be concluded that R. vesicarius methanolic extracts and fractions can be extensively used in the production of potential antioxidant, antiradical and AgNPs-Me for biomedical application on the consumer’s health.
Physiological and Competitive Characteristics of Professional Female Futsal Players
Authors: Apriantono Tommy , Bahri Samsul , Ihsani Indah Sri , Winata Bagus 
Published: March 2021

The study purpose was to examine the anaerobic and aerobic performance and also determine the influence of the anaerobic performance on specific movements during a match-play. Materials and methods. A total of 12 Indonesian professional female players from Bandung district female futsal club were recruited and enrolled to participate in this study. They were required to complete one familiarization and two experimental sessions. During the first session (laboratory test), all players performed a treadmill test to ascertain their maximum rate of oxygen consumption (VO2max) and a running-based anaerobic sprint test (RAST) to measure their anaerobic performance. For the second session (on-court test), the participants played a simulated match on the court. A training team of 5 experts carried out an investigation regarding each player’s competitive performance per match. Furthermore, the blood lactate concentration and Rate of Perceived Exertion (RPE) were assessed in the pre- and post-test for both sessions, which were separated by a week to enable the players to recover. Results. The results showed that there was no significant difference between the mean power (MP) and fatigue index (FI) (p = 0.425, p = 0.938, respectively) for anaerobic performance using Analysis of Variance (ANOVA), although, the MP and FI of team C was lower compared to A and B. Furthermore, the total number of failed passes and shot off target of team C was larger compared to B and A (for failed passes = 30 vs 20 vs 25, for shot off target 14 vs 13 vs 8). Conclusions. The results obtained indicate that there are strong associations between anaerobic capacity and explosive movements (shooting, tackling, heading and passing) among female futsal players.
A Prospective Cohort Study to Predict Running-Related Lower Limb Sports Injuries Using Gait Kinematic Parameters
Authors: Gogoi Hemantajit , Rajpoot Yajuvendra Singh , Borah Poli 
Published: March 2021

The study purpose was to follow a prospective cohort study design to use gait kinematic parameters to identify the risk factors and to develop a statistical model to predict running-related lower limb injuries of sportspersons.
Materials and methods. BTS G-WALK® gait analysis system was used to collect gait kinematic data of 87 subjects from an institute of physical education and sports science.
The subjects were followed for a full academic season after which the researcher inquired about their injury occurrences. Binary logistic regression was used to develop a prediction model to predict lower limb injuries of sportspersons.
Results. The result of the study revealed that increasing Range of Obliquity, Range of Tilt and Range of Rotation were associated with increased likelihood of future running-related lower limb injury. However, the lower Symmetry Index was associated with increase in the likelihood of future running-related lower limb injury.
Conclusions. The study confirmed that it is possible to predict injury, but for practical implication further research is essential with a bigger sample size.
Correlation of diabetes with mycotic infections: a pilot study
Authors: Munjal Manish , Mittal Naveen , Bansal Ekta , Munjal Shubham , Mehta Devambika , Arora Anurima , Garg Ayushi 
Published: March 2021

Background: The immuno-compromised individuals have a high Incidence of fungal infections of the nose and the paranasal sinuses. There is a variation in the fungal species that manifest in different subset of individuals. The species and the susceptible individuals were studied in the Punjab population, to suggest measures to attain a better outcome.Methods: 50 subjects treated for paranasal fungal infection by rhinology division of the oto-rhino-laryngology services, Dayanand Medical College and hospital, Ludhiana, were analysed. The prospective study was carried out in a period of one and a half year (June 2009 to December 2010).Results: Mycotic infections was predominantly noted in the age group 51-60 years i.e. in 14 patients (28%) followed by 41-50 years, 13 cases (26%). There were 29 (58%) of males and 21 (42%) females with a male:female ratio of 1.4:1. Amongst 50 patients with mycotic infection, 19 (38%) were diabetic. All 15 (100%) patients with zygomycosis had underlying diabetes while only 4 (21%) with aspergillosis were diabetic.Conclusions: Zygomycosis occurs usually in diabetics, while in aspergillosis the underlying morbidity may or may not be diabetes. Timely medical treatment is essential to check diabetes and species identification to select the appropriate antifungal medication.
Potencial biotecnológico de los hongos marinos en las zonas costeras de Costa Rica
Authors: Masís Ramos Stephannie , Meléndez-Navarro Paola , Méndez-Rodríguez Erika 
Published: March 2021

La micología marina consiste en un grupo diverso, cuyas características de sobrevivencia en ambientes hostiles y sus adaptaciones los convierte en atractivo para la obtención de metabolitos y diversas aplicaciones biotecnológicas. Dentro de sus utilidades, se reporta la producción de alcaloides, lípidos, enzimas, pigmentos, compuestos con aplicación médica, entre otros. Estos hongos habitan generalmente en climas tropicales, subtropicales y templados; por lo que, debido al clima tropical y posición geográfica que posee Costa Rica, el país es prometedor para la exploración y explotación de la diversidad micológica asociada a los organismos en los que suelen hospedarse los hongos marinos, como lo son las esponjas marinas, algas y plantas situadas en el mar o manglares. De esta manera, el presente artículo evidencia el potencial biotecnológico que presenta la micoflora en las zonas costeras de Costa Rica.
Materiales alternativos como oportunidad de reducción de impactos ambientales en el sector construcción
Authors: Hernández-Zamora María Fernanda , Jiménez-Martínez Sebastián Isaí , Sánchez-Monge Juan Ignacio 
Published: March 2021

Las construcciones se han convertido en un grave problema ambiental, debido a su alta exigencia de recursos naturales y la producción masiva de residuos de gran volumen que requieren un manejo especial. Debido a esto, es necesario replantear los materiales utilizados en el sector, junto con los métodos de extracción y producción, así como la aplicación de instrumentos que faciliten la disminución de los impactos asociados a las obras de construcción, desde la etapa del diseño u obtención de materias primas. De esta manera, se empleó una búsqueda bibliográfica de diversos documentos con carácter electrónico, principalmente de las bases de datos de la Universidad Nacional, entre otros buscadores académicos. El proceso metodológico se realizó a partir de una investigación cualitativa, donde la teoría y la revisión bibliográfica fueron el marco de referencia; bajo el objetivo de identificar algunos de los materiales alternativos , tales como el adobe, la madera, el cáñamo, la paja, el bambú y los ecoladrillos confeccionados con residuos domésticos , que pueden reemplazar el uso de materiales convencionales. En este sentido, la presente indagación bibliográfica permitió demostrar que los materiales alternativos son capaces de dar el mismo soporte estructural a una obra constructiva, en comparación con otros materiales convencionales. Asimismo, se destaca el valor agregado que estas opciones le otorgan al sector construcción, reduciendo las huellas ecológicas asociadas y mejorando el equilibrio ambiental, ya que se reducen los altos costos ambientales por la extracción de recursos y se minimizan los demás impactos ambientales negativos.