bluuebunny/crossref_metadata_2025 huggingface dataset:
Differences in surface chemistry of iron oxide nanoparticles result in different routes of internalization
Authors: Svitkova Barbora , Zavisova Vlasta , Nemethova Veronika , Koneracka Martina , Kretova Miroslava , Razga Filip , Ursinyova Monika , Gabelova Alena
Published: March 2021

The efficient entry of nanotechnology-based pharmaceuticals into target cells is highly desired to reach high therapeutic efficiency while minimizing the side effects. Despite intensive research, the impact of the surface coating on the mechanism of nanoparticle uptake is not sufficiently understood yet. Herein, we present a mechanistic study of cellular internalization pathways of two magnetic iron oxide nanoparticles (MNPs) differing in surface chemistry into A549 cells. The MNP uptake was investigated in the presence of different inhibitors of endocytosis and monitored by spectroscopic and imaging techniques. The results revealed that the route of MNP entry into cells strongly depends on the surface chemistry of the MNPs. While serum bovine albumin-coated MNPs entered the cells via clathrin-mediated endocytosis (CME), caveolin-mediated endocytosis (CavME) or lipid rafts were preferentially involved in the internalization of polyethylene glycol-coated MNPs. Our data indicate that surface engineering can contribute to an enhanced delivery efficiency of nanoparticles.
Axial force coefficient of APFSDS projectile
Authors: Trakic Ammar
Published: March 2021

Armor-piercing ammunition is primarily used to combat against heavy armored targets (tanks), but targets can be light armored vehicles, aircraft, warehouse, structures, etc. It has been shown that the most effective type of anti-tank ammunition in the world is the APFSDS ammunition (Armor Piercing Fin Stabilized Discarding Sabot). The APFSDS projectile flies to the target and with his kinetic energy acts on the target, that is, penetrates through armor and disables the tank and his crew. Since the projectile destroys target with his kinetic energy, then it is necessary for the projectile to have the high impact velocity.

The decrease in the velocity of a projectile, during flight, is mainly influenced by aerodynamic forces. The most dominant is the axial force due to the laid trajectory of the projectile. By knowing the axial force (axial force coefficient), it is possible to predict the impact velocity of the projectile, by external ballistic calculation, in function of the distance of the target, and to define the maximum effective range from the aspect of terminal ballistics.

In this paper two models will be presented for predicting axial force (the axial force coefficient) of an APFSDS projectile after discarding sabot. The first model is defined in STANAG 4655 Ed.1. This model is used to predict the axial force coefficient for all types of conventional projectiles. The second model for predicting the axial force coefficient of an APFSDS projectile, which is presented in the paper, is the CFD-model (Computed Fluid Dynamics).
Waste management in a university campus
Authors: Uyanik Ibrahim , Özkan Oktay , Mihçiokur Hamdi
Published: March 2021

In this study, we discussed how can be the management hierarchy and management process in a university campus. Erciyes University is in the middle of the Anatolia Region that has about 60.000 population. The university has faculty /institutional administrations and hospital-related buildings and research centers. It has an area of about 20 m2 for each person on the campus. The university is responsible in terms of legislative directives that are in operation. The waste directive is published by the university in 2017 that shares the responsibilities and distributes the tasks for each unit on the university campus. In Turkey, zero waste projects and zero waste legislation are also in operation by 2019. The importance of waste management strategy is important for Sustainable Development Goals (SDG) that is published by the United Nations and put in consideration of Times Higher Education (THE) which is one of the most confidential ranking systems for universities. There is also, environmental assessment system for university campuses, the Green-Metric. One of the grading subjects of the Council of Higher Education (YÖK) in Turkey is the zero waste strategy on the campus. Therefore, the operation of a zero-waste strategy gains importance.
Cross-heterogeneous Domain Authentication Scheme Based on Blockchain
Authors: Liu Jing , Liu Yixin , Lai Yingxu , Li Rongchen , Wu Siyu , Mian Sami
Published: March 2021

With the rising popularity of the Internet and the development of big data technology, an increasing number of organizations are opting to cooperate across domains to maximize their benefits. Most organizations use public key infrastructure to ensure security in accessing their data and applications. However, with the continuous development of identity-based encryption (IBE) technology, small- and medium-sized enterprises are increasingly using IBE to deploy internal authentication systems. To solve the problems that arise when crossing heterogeneous authentication domains and to guarantee the security of the certification process, we propose using blockchain technology to establish a reliable cross-domain authentication scheme. Using the distributed and tamper-resistant characteristics of the blockchain, we design a cross-domain authentication model based on blockchain to guarantee the security of the heterogeneous authentication process and present a cross-domain authentication protocol based on blockchain. This model does not change the internal trust structure of each authentication domain and is highly scalable. Furthermore, on the premise of ensuring security, the process of verifying the signature of the root certificate in the traditional cross-domain authentication protocol is improved to verify the hash value of the root certificate, thereby improving the authentication efficiency. The developed prototype exhibits generality and simplicity compared to previous methods.
Weddings in Korea and Ukraine
Authors: Hong Sogu
Published: March 2021

Koreans and Ukrainians are two different nations in many aspects, such as geography, language, ethnicity, culture, and so on. It may seem difficult to find something in common between them. However, in terms of folk culture, especially wedding rituals, I would say that the two nations have many things in common. This study attempts to compare the traditional wedding rituals of the two nations which were performed among commoners between the 19th and the beginning of the 20th centuries. Through this study, we can understand that the basic structure of the wedding rituals of both cultures have much in common. Even though the ritual forms and contents are different from each other, both cultures use many similar objects and symbolic expressions for the wedding ceremony. This study also deals with how women’s work, romance and new aspirations of social class transformed the marriage tradition, and how rituals were influenced by the intervention of the governments’ authority in personal life.
To Unsee the Sea
Authors: Jurišić Paula
Published: March 2021

This article provides a glimpse into the echo of the European refugee crisis in contemporary European cinema and the modes of narration deployed in representations of the
phenomenon that is rapidly changing the European political and cultural landscape.
The representation of the crisis seems to be bringing about a crisis of representation.
Mainstream media refugee images are penetrating both the big screens and television
production. Drama and victimhood are, consequently, inevitably becoming the dominant
modes of narration (See Rosi’s Fuocoammare), but a growing number of filmmakers
address the issue in rather creative ways, bravely experimenting with the nature of the
cinematic event as a whole.
INSTRUMENTO VÁLIDO PARA AVALIAÇÃO DA QUALIDADE DO CUIDADO NAS INSTITUIÇÕES DE LONGA PERMANÊNCIA PARA IDOSOS: UMA REVISÃO INTEGRATIVA
Authors: De Almeida Alexandre Márcio , Santos de Souza Nair
Published: March 2021

Como a demanda por instituições de longa permanência para idosos (ILPIs) está expandindo, e venha ser relevante para os sistemas  e saúde pública discutir o processo de avaliação das condições de saúde dos seus residentes. Em relação a estes acontecimentos, que tem despertado a preocupação a preocupação da sociedade, a interação do idoso em Instituição de Longa Permanência para Idosos (ILPIs) mostra-se como alternativa a ser considerada. Perante a este cenário, as premissas supracitadas, o presente estudo objetivou identificar, por meio de revisão integrativa, instrumentos de medida construídos especificamente para o gerenciamento e o cuidado de residentes idosos, em instituições de longa permanência. Em face do objetivo proposto, as demandas assistenciais e gerenciais das ILPI, programa para melhorar a qualidade do cuidado baseada na dimensão Atenção Centrada na Pessoa, utilizando instrumentos como Indicadores Observáveis da Qualidade do Cuidado nas Instituições de Longa Permanência para Idosos (IOQ) adaptado ao contexto nacional na versão brasileira do IOQ. Torna-se urgente a reformulação de políticas públicas que garantam um sistema de avaliação padronizado dos residentes de ILPIs no Brasil, sendo um desafio fazer com que os instrumentos desenvolvidos consigam se difundir e se efetivar no cotidiano dos profissionais dessas instituições.
An empirical analysis of factors affecting the intention of using digital wallets in Vietnam
Authors: Hoang Thi Hau , Duong Thi Hoai Nhung , Pham Hong Trang
Published: March 2021

This study investigates factors affecting consumers’ behavioral intention of using digital wallets in Vietnam. The research model consists of five independent variables, namely performance expectancy, effort expectancy, social influence, facilitating conditions, and perceived risks. The sample size of this study is 280. This study confirms that performance expectancy, effort expectancy, social influence, and facilitating conditions positively influence the behavioral intention of using digital wallets. Importantly, performance expectancy and effort expectancy are the most significant determinants of behavioral intention. Perceived risks are found to negatively affect the behavioral intention of using digital wallets. These findings indicate that service providers ought to focus on enhancing digital wallets’ user-friendliness, features, and functions to improve financial transactions via digital wallets. The security system of digital wallets also needs improving to reduce risks, thereby encouraging Vietnamese consumers to utilize the service.
A study of the factors affecting the willingness to engage in business-university cooperation
Authors: Tran Tu Uyen
Published: March 2021

While developed countries have been aware of the important role and built successful models of business-university cooperation, in Vietnam, this cooperation has not been paid enough attention to and has not yet been implemented. To improve the situation, this study develops a model of factors that affect the businesses willingness to participate in the businessuniversity cooperation of Vietnamese companies. Utilizing data collected from interviews with 58 enterprises and applying the EFA factor analysis and regression analysis, the study finds that two factors, which are the awareness of benefits, and barriers, affect the willingness to participate in business-university cooperation have been found with a regression model. While awareness of benefits promotes the businesses willingness, Barriers prevent owners/ managers from engaging in such relationships. Based on the research results, some solutions are proposed to enhance the willingness of companies.
DEVELOPMENT AND VALIDATION OF AN INDUSTRY 4.0 ADAPTATION POTENTIAL SCALE (4IRAPS)
Authors: Sözbilir Fikret
Published: March 2021

The aim of this study was to develop a scale that can measure the potential of adapting to Industry 4.0, which refers to the fourth industrial revolution described as a combination of the innovation of various digital technologies rapidly developed in recent years. In addition, the reliability and validity of the Industry 4.0 Adaptation Potential (4IRAPS) is demonstrated. This research was conducted in two stages of a pilot and a main study. The data was collected from 174 participants enrolled in technical and management departments at the graduate and associate degree levels of two different universities. A 50-item questionnaire concerning Industry 4.0 prepared by experts experienced in this field was applied to the participants. As a result of a factor analysis, 30 items and 11 subscales with low a factor load and reliability level were removed from the questionnaire. The reliability and validity of 4IRAPS were verified by” the analyses via PLS-SEM. Finally, the remaining four sub-dimensions referring to Industry 4.0 were labelled as interested, effort for adaptation, readiness, and pessimism. This study developed the first scale of the industry 4.0 adaptation potential. The scale consists of four sub-dimensions and 17 items. It was determined that this scale was statistically reliable and valid.
AX UMa, an ab-type RR Lyrae Star with a Rapidly Decreasing Pulsation Period, and Its Binarity
Authors: Li L.-J. , Qian S.-B. , Zhu L.-Y. , He J.-J. , Fang X.-H.
Published: March 2021

The pulsation periods of RR Lyrae stars usually vary with time, and they are often used as probes to study the mechanism behind the variation. After the early discovery that the pulsation period of the RR Lyrae star AX UMa decreased rapidly, in further research, we made multiband photometric observations of this star using the Sino-Thai 70 cm telescope and the 60 cm telescope at Yunnan Observatories, and collected its light-curve data from several photometry sky surveys. The O–C diagram confirmed that AX UMa has a rapid period decrease with a rate of −7.752 ± 0.005 days Myr−1, which indicates that it is the fastest-period decreasing ab-type RR Lyrae star in the Galactic field. Moreover, the O – C residuals contain additional periodic variations. We suppose that the variation with a long period is probably caused by the light-travel time effect as the star orbits in a binary system. The calculation shows that the lower mass limit of the companion is about 1 M
⊙. Combined with the full amplitudes and color indexes, we suggested that the companion is probably a hot subdwarf star. We compared the light curves of AX UMa and those of another binary evolution pulsator, OGLE-BLG-RRLYR-02792, and found that the former shows the characteristics of ab-type RR Lyrae stars, while the latter is more like an extreme long-period c-type RR Lyrae star. However, the absence of a bump in the light curves implies that the mass loss has occurred in the outer atmosphere of AX UMa. The special features of AX UMa make it worth more attention and further observations.
Cosmology with Galaxy Cluster Weak Lensing: Statistical Limits and Experimental Design
Authors: Wu Hao-Yi , Weinberg David H. , Salcedo Andrés N. , Wibking Benjamin D.
Published: March 2021

We forecast constraints on the amplitude of matter clustering σ
8(z) achievable with the combination of cluster weak lensing and number counts, in current and next-generation weak lensing surveys. We advocate for an approach, analogous to galaxy–galaxy lensing, in which the observables in each redshift bin are the mean number counts and the mean weak lensing profile of clusters above a mass proxy threshold. The primary astrophysical nuisance parameter is the logarithmic scatter

between the mass proxy and true mass near the threshold. For surveys similar to the Dark Energy Survey (DES), the Roman Space Telescope High Latitude Survey (HLS), and the Rubin Observatory Legacy Survey of Space and Time (LSST), we forecast aggregate precision on σ
8 of 0.26%, 0.24%, and 0.10%, respectively, if the mass–observable scatter is known externally to

. These constraints would be degraded by about 20% for

in the case of DES or HLS and for

for LSST. A 1 month observing program with Roman Space Telescope targeting ∼2500 massive clusters could achieve a ∼ 0.5% constraint on σ
8(z = 0.7) on its own, or a ∼ 0.33% constraint in combination with the HLS. Realizing the constraining power of clusters Requires accurate knowledge of the mass–observable relation and stringent control of systematics. We provide analytic approximations to our numerical results that allow for easy scaling to other survey assumptions or other methods of cluster mass estimation.
The RS CVn–type Star GT Mus Shows Most Energetic X-Ray Flares Throughout the 2010s
Authors: Sasaki Ryo , Tsuboi Yohko , Iwakiri Wataru , Nakahira Satoshi , Maeda Yoshitomo , Gendreau Keith , Corcoran Michael F. , Hamaguchi Kenji , Arzoumanian Zaven , Markwardt Craig B. , Enoto Teruaki , Sato Tatsuki , Kawai Hiroki , Mihara Tatehiro , Shidatsu Megumi , Negoro Hitoshi , Serino Motoko
Published: March 2021

We report that the RS CVn–type star GT Mus (HR 4492, HD 101379+HD 101380) was the most active star in the X-ray sky in the last decade in terms of the scale of recurrent energetic flares. We detected 11 flares from GT Mus in 8 yr of observations with the Monitor of All-sky X-ray Image (MAXI) from 2009 August to 2017 August. The detected flare peak luminosities were 1–4 × 1033 erg s−1 in the 2.0–20.0 keV band for its distance of 109.6 pc. Our timing analysis showed long durations (τ
r + τ
d) of 2–6 days with long decay times (τ
d) of 1–4 days. The released energies during the decay phases of the flares in the 0.1–100 keV band were in the range of 1–11 × 1038 erg, which are at the upper end of the observed stellar flare. The released energies during the whole duration were in the range of 2–13 × 1038 erg in the same band. We carried out X-ray follow-up observations for one of the 11 flares with the Neutron star Interior Composition Explorer (NICER) on 2017 July 18 and found that the flare cooled quasi-statically. On the basis of a quasi-static cooling model, the flare loop length is derived to be 4 × 1012 cm (or 60 R
☉). The electron density is derived to be 1 × 1010 cm−3, which is consistent with the typical value of solar and stellar flares (1010–13 cm−3). The ratio of the cooling timescales between radiative (τ
rad) and conductive (τ
cond) cooling is estimated to be τ
rad ∼ 0.1 τ
cond from the temperature; thus, radiative cooling was dominant in this flare.
On the Progenitors of AM CVn Stars as LISA Sources: The Evolved Donor Star Channel
Authors: Liu Wei-Min , Jiang Long , Chen Wen-Cong
Published: March 2021

The space gravitational wave (GW) detector Laser Interferometer Space Antenna (LISA) that is planned to be launched in the early 2030s will detect the low-frequency GW signals in the Galaxy. AM CVn stars were generally thought to be important low-frequency GW sources. Employing the MESA code, in this work we calculate the evolution of a great number of binary systems consisting of a white dwarf (WD) and a main sequence (MS) star, and diagnose whether their descendant-AM CVn stars will be visible with LISA. The simulated results show that the progenitors of these LISA sources, within a distance of 1 kpc, are WD–MS binaries with a donor star of 1.0–1.4 M
⊙ (for initial WD mass of 0.5 M
⊙) or 1.0–2.0 M
⊙ (for initial WD mass of 0.7 M
⊙), and an initial orbital period slightly smaller than the bifurcation period. Our simulations also indicate that 10 verification AM CVn sources can be reproduced by the standard magnetic braking model, and are potential LISA sources. Based on the birth rate of AM CVn stars simulated by the population synthesis, the birth rate of AM CVn-LISA sources evolving from the evolved donor star channel within a distance of 1 kpc can be estimated to be (0.6–1.4) × 10−6 yr−1, and the predicted number of AM CVn-LISA sources is about 340–810. Therefore, the evolved donor star channel plays an important role in forming AM CVn-LISA sources in the Galaxy.
The Perseus ALMA Chemistry Survey (PEACHES). I. The Complex Organic Molecules in Perseus Embedded Protostars
Authors: Yang Yao-Lun , Sakai Nami , Zhang Yichen , Murillo Nadia M. , Zhang Ziwei E. , Higuchi Aya E. , Zeng Shaoshan , López-Sepulcre Ana , Yamamoto Satoshi , Lefloch Bertrand , Bouvier Mathilde , Ceccarelli Cecilia , Hirota Tomoya , Imai Muneaki , Oya Yoko , Sakai Takeshi , Watanabe Yoshimasa
Published: March 2021

To date, about two dozen low-mass embedded protostars exhibit rich spectra with lines of complex organic molecules (COMs). These protostars seem to possess a different enrichment in COMs. However, the statistics of COM abundance in low-mass protostars are limited by the scarcity of observations. This study introduces the Perseus ALMA Chemistry Survey (PEACHES), which aims at unbiasedly characterizing the chemistry of COMs toward the embedded (Class 0/I) protostars in the Perseus molecular cloud. Of the 50 embedded protostars surveyed, 58% of them have emission from COMs. 56%, 32%, and 40% of the protostars have CH3OH, CH3OCHO, and N-bearing COMs, respectively. The detectability of COMs depends neither on the averaged continuum brightness temperature, a proxy of the H2 column density, nor on the bolometric luminosity and the bolometric temperature. For the protostars with detected COMs, CH3OH has a tight correlation with CH3CN, spanning more than two orders of magnitude in column densities normalized by the continuum brightness temperature, suggesting a chemical relation between CH3OH and CH3CN and a large chemical diversity in the PEACHES samples at the same time. A similar trend with more scatter is also found between all identified COMs, which hints at a common chemistry for the sources with COMs. The correlation between COMs is insensitive to the protostellar properties, such as the bolometric luminosity and the bolometric temperature. The abundance of larger COMs (CH3OCHO and CH3OCH3) relative to that of smaller COMs (CH3OH and CH3CN) increases with the inferred gas column density, hinting at an efficient production of complex species in denser envelopes.
Discovery of an Ultra-faint Stellar System near the Magellanic Clouds with the DECam Local Volume Exploration Survey
Authors: Cerny W. , Pace A. B. , Drlica-Wagner A. , Ferguson P. S. , Mau S. , Adamów M. , Carlin J. L. , Choi Y. , Erkal D. , Johnson L. C. , Li T. S. , Martínez-Vázquez C. E. , Mutlu-Pakdil B. , Nidever D. L. , Olsen K. A. G. , Pieres A. , Tollerud E. J. , Simon J. D. , Vivas A. K. , James D. J. , Kuropatkin N. , Majewski S. , Martínez-Delgado D. , Massana P. , Miller A. E. , Neilsen E. H. , Noël N. E. D. , Riley A. H. , Sand D. J. , Santana-Silva L. , Stringfellow G. S. , Tucker D. L. ,   (DELVE Collaboration)
Published: March 2021

We report the discovery of a new ultra-faint stellar system found near the Magellanic Clouds in the DECam Local Volume Exploration Survey. This new system, DELVE J0155−6815 (DELVE 2), is located at a heliocentric distance of D
⊙ = 71 ± 4 kpc, which places it at a 3D physical separation of 12 ± 3 kpc from the center of the Small Magellanic Cloud and

from the center of the Large Magellanic Cloud (LMC). DELVE 2 is identified as a resolved overdensity of old (τ > 13.3 Gyr) and metal-poor (

dex) stars with a projected half-light radius of

and an absolute magnitude of

. The size and luminosity of DELVE 2 are consistent with both the population of recently discovered ultra-faint globular clusters and the smallest ultra-faint dwarf galaxies. However, its photometrically derived age and metallicity would place it among the oldest and most metal-poor globular clusters in the Magellanic system. In the absence of spectroscopic measurements of the system’s metallicity dispersion and internal kinematics, we are unable to conclusively classify this system at this time. DELVE 2 is detected in Gaia DR2 with a clear proper-motion signal, with multiple blue horizontal-branch stars near the centroid of the system with proper motions consistent with the systemic mean. We measure the system proper motion to be

=

mas yr−1. We compare the spatial position and proper motion of DELVE 2 with simulations of the accreted satellite population of the LMC and find that it is very likely to be associated with the LMC.
VLBI Observations of Supernova PTF11qcj: Direct Constraints on the Size of the Radio Ejecta
Authors: Palliyaguru N. T. , Corsi A. , Pérez-Torres M. , Varenius E. , Van Eerten H.
Published: March 2021

We present High Sensitivity Array and enhanced Multi-Element Remotely Linked Interferometer Network observations of the radio-loud broad-lined Type Ic supernova PTF11qcj obtained ∼7.5 yr after the explosion. Previous observations of this supernova at 5.5 yr since explosion showed a double-peaked radio light curve accompanied by a detection in the X-rays, but no evidence for broad Hα spectral features. The Very Long Baseline Interferometry (VLBI) observations presented here show that the PTF11qcj GHz radio ejecta remains marginally resolved at the submilliarcsecond level ≈7.5 yr after the explosion, pointing toward a nonrelativistic expansion. Our VLBI observations thus favor a scenario in which the second peak of the PTF11qcj radio light curve is related to the strong interaction of the supernova ejecta with a circumstellar medium of variable density, rather than to the emergence of an off-axis jet. Continued VLBI monitoring of PTF11qcj in the radio may further strengthen this conclusion.
Testing the High-latitude Curvature Effect of Gamma-Ray Bursts with Fermi Data: Evidence of Bulk Acceleration in Prompt Emission
Authors: Li Liang , Zhang Bing
Published: March 2021

When a gamma-ray burst (GRB) emitter stops emission abruptly, the observer receives rapidly fading emission from high latitudes with respect to the line of sight, known as the “curvature effect.” Identifying such emission from GRB prompt-emission lightcurves would constrain the radius of prompt emission from the central engine and the composition of GRB jets. We perform a dedicated search of high-latitude emission (HLE) through spectral and temporal analyses of a sample of single-pulse bursts detected by the Gamma-ray Burst Monitor on board the Fermi satellite. We identify HLE from a subsample of bursts and constrain the emission radius to be R
GRB ∼ (1015–1016) cm from the central engine. Some bursts have the HLE decay faster than predicted by a constant Lorentz factor jet, suggesting that the emission region is undergoing acceleration during prompt emission. This supports the Poynting-flux-dominated jet composition for these bursts. The conclusion is consistent with previous results drawn from spectral-lag modeling of prompt emission and HLE analysis of X-ray flares.
3D Solar Coronal Loop Reconstructions with Machine Learning
Authors: Chifu Iulia , Gafeira Ricardo
Published: March 2021

The magnetic field plays an essential role in the initiation and evolution of different solar phenomena in the corona. The structure and evolution of the 3D coronal magnetic field are still not very well known. A way to ascertain the 3D structure of the coronal magnetic field is by performing magnetic field extrapolations from the photosphere to the corona. In previous work, it was shown that by prescribing the 3D-reconstructed loops’ geometry, the magnetic field extrapolation produces a solution with a better agreement between the modeled field and the reconstructed loops. This also improves the quality of the field extrapolation. Stereoscopy, which uses at least two view directions, is the traditional method for performing 3D coronal loop reconstruction. When only one vantage point of the coronal loops is available, other 3D reconstruction methods must be applied. Within this work, we present a method for the 3D loop reconstruction based on machine learning. Our purpose for developing this method is to use as many observed coronal loops in space and time for the modeling of the coronal magnetic field. Our results show that we can build machine-learning models that can retrieve 3D loops based only on their projection information. Ultimately, the neural network model will be able to use only 2D information of the coronal loops, identified, traced, and extracted from the extreme-ultraviolet images, for the calculation of their 3D geometry.
Feeding ecology of the Green-cheeked Parakeet, Pyrrhura molinae (Psittaciformes, Psittacidae), in a subtropical forest of Argentina
Authors: Benavídez Analía , Tallei Ever , Lilian Echevarría Ada , Rivera Luis
Published: March 2021

Although there are studies on certain aspects of the feeding ecology of several species of Neotropical parrots, there is scarce ecological information aboutPyrrhura molinae– a Psittacidae species which is widely distributed in South America and abundant in the Yungas of Argentina. For two years (May 2014 to June 2016), the composition and seasonal variation in the Green-cheeked Parakeet diet in the Yungas Piedmont forest in Jujuy, Argentina were examined. Furthermore, fruiting phenology transects were established to evaluate food resource availability and the patterns of food resource used by the Green-cheeked Parakeet. In 214 food plant trees, it was found that ﬂower and dry fruit availability was highest in the dry season, and fleshy fruit production peaked in the wet season, but these phenology patterns for aged plant species suggest that there were no significant differences in food availability. The consumption of 18 plant species was recorded, beingCeltis iguanaea(30.73%) andTrema micrantha(22.01%) the most consumed species. In terms of food items, fruits were the most consumed items, followed by seeds and flowers and, to a lesser extent, nectar and leaves. Levins’ niche breadth showed varying levels of diet specialisation amongst seasons, which was narrower (B = 0.28) in the wet season, indicating specialisation in diet during this season. There was a medium overlap in parakeet diet between seasons (Morisita Index = 0.59). We did not find a statistically significant relationship between resource availability and food use, but expansion and contraction in Levins Index and variation in food items consumed throughout the year and season demonstrate high flexibility in the diet. Like other congeners, the Green-cheeked Parakeet has a flexible diet that could be adjusted to the seasonal availability of food resources. These data may contribute to the design of conservation plans for the species and its habitat.
Lost in the matrix : rationalisations en tension pour les ingénieurs aéronautiques
Authors: Coutant Hadrien
Published: March 2021

Les organisations industrielles contemporaines, en particulier les organisations « matricielles », supposées répondre aux limites des organisations bureaucratiques, sont caractérisées par une multiplication des dispositifs de rationalisation. Poursuivant des objectifs différents, quoique tous orientés vers une recherche de plus grande efficacité productive, ces dispositifs se déclinent en diverses rationalisations formelles qui entrent bien souvent en tension les unes avec les autres. L’étude de l’organisation d’une division de recherche et développement en électronique et logiciel aéronautiques montre que ces tensions entre rationalisations ont des effets paradoxaux. Plutôt que de rendre l’organisation plus prévisible, ces dispositifs entraînent à la fois une repolitisation de l’organisation et le renforcement d’une collégialité technique. Au-delà de l’étude des dysfonctionnements bureaucratiques, l’article propose une réflexion sur les jeux locaux induits par les espaces de tensions entre rationalisations.
A Gronwall lemma for functions of two variables and its application to partial differential equations of fractional order
Authors: Idczak Dariusz
Published: March 2021

In the paper, a new Gronwall lemma for functions of two variables with singular integrals is proved. An application to weak relative compactness of the set of solutions to a fractional partial differential equation is given.
Determination of the Elements of Architecture Students' Readiness to Conduct Professional Activities
Authors: Akimova Olga , Dorozhkin Evgenij , Chapaev Nikolay , Kiseleva Anna , Stroganova Alina
Published: March 2021

The relevance of the study is due to higher requirements for the professional training of engineering specialists and the need to determine the most significant aspects of their readiness to conduct professional activities. Focus on certain training aspects will make it possible to increase both the quality and the speed of specialist training, as well as contribute to their personal motivation and help them reveal their talents. The purpose of the study is to identify the elements of archi-tecture student readiness to conduct professional activities. The study took place at the Ural State University of Architecture and Art (Russia, Yekaterinburg); it involved 120 four- and five-year-students of the Faculty of Architecture, as well as 12 faculty teachers and 154 graduates of different graduation years who have from 5 to 20 years of professional experience. Based on the analysis of available research on professionalism and professional readiness, as well as a preliminary participant survey, a number of elements of students' readiness for professional activities have been identified. The concept of students' readiness to conduct pro-fessional activities has been clarified; it is described as complex integrative struc-ture, which simultaneously reflects the level of development of professionally important qualities and abilities of specialists, especially their attitude to profes-sion. The elements of students' readiness to conduct professional activities have been identified: motivational-axiological, informational-cognitive, activity-oriented, personality-reflexive. The survey participants described the elements that they believed would most contribute to professional readiness: motivational-axiological (22% of participants), informational-cognitive (18.8% of participants), personality-reflexive (16.7% of participants) and activity-oriented (13.4%). The study can be useful for vocational education teachers to help them identify the in-fluence of students' personal characteristics on the successful development of their readiness for professional activities.
Features of the Implementation of Learning Based on Modular Technology in the Corporate Training Center
Authors: Plaksina Lyubov , Lyzhin Anton , Guzanov Boris , Tumakov Vyacheslav , Glukhikh Alyona
Published: March 2021

The research aims to identify and substantiate the organizational and pedagogical conditions for the effective implementation of modular technology for the devel-opment of professional competencies in welder students in a corporate training center. The practical analysis of student achievements based on the proposed modular training system with the participation of two groups of men undergoing vocational training (22 people in each of them) showed that the experimental group provided more qualitative average answers to 9 out of 20 test questions, and the total average score was higher in this group. The experimental group also showed statistically significant and higher average scores in 5 practical tests. The results of the study can be put into practice to improve the quality of engineering training in corporate training centers.
Analysis of Mobile Cloud Computing
Authors: Mishra Sushruta , Mohapatra Sunil Kumar , Mishra Brojo Kishore , Sahoo Soumya
Published: March 2021

This chapter describes how cloud computing is an emerging concept combining many fields of computing. The foundation of cloud computing is the delivery of services, software and processing capacity over the Internet, reducing cost, increasing storage, automating systems, decoupling of service delivery from underlying technology, and providing flexibility and mobility of information. However, the actual realization of these benefits is far from being achieved for mobile applications and open many new research questions. Together with an explosive growth of the mobile applications and emerging of cloud computing concept, mobile cloud computing (MCC) has been introduced to be a potential technology for mobile services. With this importance, this chapter provides an overview of mobile cloud computing in which its definitions, architecture, and advantages have been presented. It presents an in-depth knowledge of various aspects of Mobile Cloud Computing (MCC). We give a definition of mobile cloud computing and provide an overview of its features.
Examining of QoS in Cloud Computing Technologies and IoT Services
Authors: Chowdhury Akash , Mukherjee Swastik , Banerjee Sourav
Published: March 2021

The various services that are offered by IoT and Cloud Service Providers (CSPs) to the customers today feature a pay-per-use service-charging policy. Customers can choose and avail these services when they want, how they want, and from where they want on demand. Demand for these services has increased drastically over the years among individuals and enterprises worldwide, and thus, it is very important to keep up good Quality of Service (QoS). This chapter highlights the history of internet, the gradual evolution of cloud computing, the reasons behind it, evolution and concepts of the Internet of Things (IoT), CloudIoT and its necessities, and various applications and service fields of CloudIoT. This chapter also precisely highlights various concepts regarding maintenance of good QoS, controversies in QoS maintenance, different parameters that the QoS depends on, various problems faced in maintaining those parameters, and the possible solutions for overcoming those problems. Possible directions towards future works are also highlighted in this chapter.
Unique Taxonomy for Evaluating Fog Computing Services
Authors: Bhardwaj Akashdeep , Goundar Sam
Published: March 2021

Cloud computing has slowly but surely become the foremost service provider for information technology applications and platform delivery. However, Cloud issues continue to exist, like cyberattacks, slow last mile latency, and clouds lack client-centric and location-aware applications to process real time data for efficient and customized application delivery. As an alternative, Fog Computing has the potential to resolve these issues by extending the Cloud service provider's reach to the edge of the Cloud network model, right up to the Cloud service consumer. This enables a whole new state of applications and services which increases the security, enhances the cloud experience and keeps the data close to the user. This research article presents a review on the academic literature research work on Fog Computing, introduces a novel taxonomy to classify cloud products based on Fog computing elements and then determine the best fit Fog Computing product to choose for the Cloud service consumer.
Architecture for Big Data Storage in Different Cloud Deployment Models
Authors: Thota Chandu , Manogaran Gunasekaran , Lopez Daphne , Sundarasekar Revathi
Published: March 2021

Cloud Computing is a new computing model that distributes the computation on a resource pool. The need for a scalable database capable of expanding to accommodate growth has increased with the growing data in web world. More familiar Cloud Computing vendors such as Amazon Web Services, Microsoft, Google, IBM and Rackspace offer cloud based Hadoop and NoSQL database platforms to process Big Data applications. Variety of services are available that run on top of cloud platforms freeing users from the need to deploy their own systems. Nowadays, integrating Big Data and various cloud deployment models is major concern for Internet companies especially software and data services vendors that are just getting started themselves. This chapter proposes an efficient architecture for integration with comprehensive capabilities including real time and bulk data movement, bi-directional replication, metadata management, high performance transformation, data services and data quality for customer and product domains.
Design and Development of Framework for Platform Level Issues in Fog Computing
Authors: Bhavsar Sejal Atit , Modi Kirit J
Published: March 2021

Fog computing is a paradigm that extends cloud computing services to the edge of the network. Fog computing provides data, storage, compute and application services to end users. The distinguishing characteristics of fog computing are its proximity to the end users. The application services are hosted on network edges like on routers, switches, etc. The goal of fog computing is to improve the efficiency and reduce the amount of data that needs to be transported to cloud for analysis, processing and storage. Due to heterogeneous characteristics of fog computing, there are some issues, i.e. security, fault tolerance, resource scheduling and allocation. To better understand fault tolerance, we highlighted the basic concepts of fault tolerance by understanding different fault tolerance techniques i.e. Reactive, Proactive and the hybrid. In addition to the fault tolerance, how to balance resource utilization and security in fog computing are also discussed here. Furthermore, to overcome platform level issues of fog computing, Hybrid fault tolerance model using resource management and security is presented by us.
Comparative Study for Different Provisioning Policies for Load Balancing in Cloudsim
Authors: Albdour Layla
Published: March 2021

Distributing application requests across applications located in different datacenters with in cloud equally must be provided by cloud load balancing. In this paper, we compare different provisioning policies within cloud for virtual machines and workloads, where we are focusing on how to distribute the processing power between virtual machines and how to distribute workload among virtual machines. Cloudsim is the simulation plate form used to test the different distributions scenarios to check the performance on makespan, average turnaround time, bandwidth utilization and CPU utilization. Result showed the difference in performance between the three tested provisioning schemes, where the space-shared gives better readings for the selected performance metrics.
A Hybrid Batch Mode Fault Tolerance Strategy in Desktop Grids
Authors: Rani Geeta , Bansal Jyoti
Published: March 2021

Desktop grids make use of unused resources of personal computers provided by volunteers to work as a huge processor and make them available to users that need them. The rate of heterogeneity, volatility, and unreliability is higher in case of a desktop grid in comparison to conventional systems. Therefore, the application of fault tolerance strategies becomes an inevitable requirement. In this article, a hybrid fault tolerance strategy is proposed which works in three phases. First, two phases deal with the task and resource scheduling in which appropriate scheduling decisions are taken in order to select the most suitable resource for a task. Even if any failure occurs, it is then recovered in the third phase by using rescheduling and checkpointing. The proposed strategy is compared against existing hybrid fault tolerance scheduling strategies and ensures a 100% success rate and processor utilization and outperforms by a factor of 3.5%, 0.4%, and 0.1% when turnaround time, throughput, and makespan, respectively, are taken into account
Performability Modeling of Distributed Systems and Its Formal Methods Representation
Authors: Khan Razib Hayat
Published: March 2021

A distributed system is a complex system. Developing complex systems is a demanding task when attempting to achieve functional and non-functional properties such as synchronization, communication, fault tolerance. These properties impose immense complexities on the design, development, and implementation of the system that incur massive effort and cost. Therefore, it is vital to ensure that the system must satisfy the functional and non-functional properties. Once a distributed system is developed, it is very difficult and demanding to conduct any modification in its architecture. As a result, the quantitative analysis of a complex distributed system at the early stage of the development process is always an essential and intricate endeavor. To meet the above challenge, this chapter introduces an extensive framework for performability evaluation of a distributed system. The goal of the performability modeling framework is to consider the behavioral change of the system components due to failures. This reveals how such behavioral changes affect the system performance.
The Role of Value Facilitation Regarding Cloud Service Provider Profitability in the Cloud Ecosystem
Authors: Herzfeldt Alexander , Floerecke Sebastian , Ertl Christoph , Krcmar Helmut
Published: March 2021

With the increasing maturity of cloud technologies and the growing demand from customers, the cloud computing ecosystem has been expanding continuously with both incumbents and new entrants, whereby it has become more distributed and less transparent. For cloud service providers previously focusing on growth strategies, it is now necessary to shift the attention to providing service efficiently, as well as profitably. Based on 14 explorative interviews with cloud service experts, the relationship between cloud service provider profitability and value facilitation, which stands for the capability to build up resources in advance of future customer engagements, is investigated. The results indicate a positive relationship between cloud service profitability and value facilitation and deliver valuable insights for both researchers and practitioners. In particular, guidelines on how to design profitable cloud service offerings are discussed.
Anomaly Detection in Cloud Computing and Internet of Things Environments
Authors: Cherkaoui Rachid , Zbakh Mostapha , Braeken An , Touhafi Abdellah
Published: March 2021

This chapter contains the state of the art of the latest security issues of cloud computing as well as security issues of internet of things (IoT) applications. It discusses the integration of IoT platforms with cloud computing services, security of the hosted data, intrusion and anomaly detection techniques used to detect attacks in virtualized networks. The chapter also discusses some of the lightweight anomaly detection techniques to use in integrated constrained devices' ecosystems with cloud computing environments. This chapter focuses on efficient integration of cloud hosting with IoT applications as well as integration of lightweight intrusion detection systems in the latter environments.
Dynamic Capabilities of Decision-oriented Service Systems
Authors: Schmidt Rainer , Möhring Michael , Zimmerman Alfred
Published: March 2021

A new class of information system architecture, decision-oriented service systems, is spreading more and more. Decision-oriented service systems provide services that support decisions in business processes and products based on the capabilities of cloud-computing environments. To pave the way for the creation of design methods of business processes and products based on decision-oriented service systems, this article introduces a capability-oriented approach. Starting from technological capabilities, more abstract operational and dynamic capabilities are created. The framework created is based on an integrated conceptualization of decision-oriented service systems that allows capturing synergetic effects. By creating the framework, the gap between the technological capabilities of technologies and the strategic goals of enterprises shall be narrowed.