bluuebunny/crossref_metadata_2025 huggingface dataset:
Metalated isocyanides: formation, structure, and reactivity
Authors: Altundas Bilal , Marrazzo John-Paul R. , Fleming Fraser F.
Published: August 2020

This review surveys the formation, structure, and properties of metalated isocyanides, a synthetic multi-tool with nucleophilic and electrophilic sites, providing a powerful approach to rapidly access complex molecules.
The energy of fcc and hcp foams
Authors: Hutzler S. , Dunne F. F. , Kraynik A. M. , Weaire D.
Published: August 2020

We present Surface Evolver evaluations of the difference in energy between face-centred cubic and hexagonal close-packed foams for liquid fractions from the dry to the wet limit, together with explicit expressions derived from first principles.
ZIF-62: a mixed linker metal–organic framework for triboelectric nanogenerators
Authors: Khandelwal Gaurav , Maria Joseph Raj Nirmal Prashanth , Kim Sang-Jae
Published: August 2020

A mixed linker metal–organic framework for TENG and self-powered fitness tracking.
Recommending Hearing Assessment for Individuals With Dementia: A Survey of Medical Professionals
Authors: Gurevich Naomi , Ramrattan Heidi , Kubalanza Mary , Osmelak Danielle R. , Boese Jenna
Published: August 2020

Objectives

Older adults are at risk for age-related hearing loss and for dementia. Hearing loss increases the risk of dementia and accelerates cognitive decline. There is no cure for dementia, but hearing loss is treatable. Medical professionals who work with individuals with dementia are surveyed to explore whether recommendations made to individuals diagnosed with dementia include hearing assessments.

Method

A convenience sample of 85 medical professionals in California, Illinois, and Indiana responded to paper surveys in October 2018–April 2019.

Results

Of the 85 participants, 69 had some level of involvement with dementia. Of these, 16 (23%) reported recommending hearing assessment, and only one (1.45%) reported considering hearing assessment in the top three priorities of recommendations.

Conclusions

Hearing assessment is not currently a priority for the surveyed medical professionals who work with dementia populations. Advocacy is needed to close the gap between research and practice.
Mechanical analysis of microstructured polymer optical fibres with different drawing pressures
Authors: Leal‐Junior A. , Díaz C. , Frizera A. , Mergo P. , Marques C.
Published: August 2020

This Letter presents the mechanical analysis of polymethyl methacrylate microstructured polymer optical fibres drawn at different pressures. The fibres were drawn at 200, 400 and 600 mmH2 O, where all the samples have a diameter close to 250 µm. Tensile tests were performed in five samples of each drawing pressure and the statistical analysis was applied to Young's modulus, yield stress, strain at breakage and Poisson's ratio of each sample. Results show a statistically significant increase of Young's modulus with the increase in drawing pressure, whereas the strain at breakage presented the opposite behaviour, with its values decreasing as the drawing pressure increases. Furthermore, the Poisson's ratio, as well as, the yield stress do not show a statistically significant variation with the different drawing pressure analysed.
Analytical modelling of air‐gap magnetic field of interior permanent magnet synchronous motors
Authors: Wu Zhipeng , Zuo Shuguang , Hu Shenglong , Hu Xiaorui
Published: August 2020

A general analytical model, which is applied to pre‐estimate the air‐gap magnetic field of interior permanent magnet synchronous motors (IPMSM) under the no‐load and load conditions, is proposed in this study. First, the analytical formulas of both the slotless permanent magnetic field and the armature reaction magnetic field are derived, respectively, by virtue of solving the Laplace field equation in polar coordinates. Then, the complex relative permeance is employed to account for the slotting effect. Subsequently, the proposed analytical model, which can reflect the spatial and temporal distribution characteristics of the air‐gap magnetic field, has been applied in a 4‐pole‐24‐slot IPMSM as an example. Finally, the analytical air‐gap magnetic field with the spatial order and frequency characteristics is validated by the finite‐element result. Additionally, the consistency between the analytical and finite‐element results further indicates that the proposed analytical model is effective.
Generative adversarial framework‐based one‐day‐ahead forecasting method of photovoltaic power output
Authors: Du Liufeng , Zhang Linghua , Wang Xu
Published: August 2020

Accurately forecasting the energy yields of photovoltaic (PV) systems is of great benefit to the power optimization of smart grid. However, most existing data‐driven paradigm‐based forecasting methods often suffer from the diversity of power fluctuation patterns, which results in poor performance while dealing with distributed PV systems that are more sensitive to external factors. To overcome this problem, this study first formulates an input data scheme based on historical PV power data, in which a novel decomposition algorithm is proposed to separate the structural information and fluctuation components in the power data. Then, a forecasting model based on the generative adversarial framework is developed, whose generative module can obtain the ability to learn the desired feature distribution with the discriminator, rather than selecting features via a certain trained preference. Moreover, the proposed method takes into account some meteorological elements to further characterise the power fluctuations. Extensive self‐evaluation and comparison with several state‐of‐the‐art methods highlight the superiority of the proposed method.
Relations among structural parameters in barred galaxies with a direct measurement of bar pattern speed
Authors: Cuomo V. , Aguerri J. A. L. , Corsini E. M. , Debattista V. P.
Published: August 2020

We investigate the relations between the properties of bars and their host galaxies in a sample of 77 nearby barred galaxies, spanning a wide range of morphological types and luminosities, with 34 SB0-SBa and 43 SBab-SBc galaxies. The sample includes all the galaxies with reliable direct measurement of their bar pattern speed based on long-slit or integral-field stellar spectroscopy using the Tremaine-Weinberg method. We limited our analysis to the galaxies with a relatively small relative error on the bar pattern speed (≤50%) and that do not host an ultrafast bar. For each galaxy, we collected the radius, strength, pattern speed, corotation radius, and rotation rate for the bar and we also collected the Hubble type and absolute SDSSr-band magnitude. We also used literature bulge-to-total luminosity ratios for a subsample of 53 galaxies with an available photometric decomposition. We confirmed earlier observational findings that longer bars rotate at lower bar pattern speeds, shorter bars are weaker, and bars with a low rate of bar rotation rotate at faster bar pattern speeds and have smaller corotation radii. In addition, we found that stronger bars rotate at lower bar pattern speeds, as predicted from the interchange of angular momentum during bar evolution, which in turn may depend on different galaxy properties. Moreover, we report that brighter galaxies host longer bars, which rotate at lower bar pattern speeds and have larger corotation radii. This result is in agreement with a scenario of downsizing in bar formation, if more massive galaxies formed earlier and had sufficient time to slow down, grow in length, and push corotation outwards.
Roboterassistierte Thoraxchirurgie bei Mediastinaltumoren
Authors: Eichhorn Martin , Haag Johannes , Grünewald Christiane , Reimer Peter , Winter Hauke
Published: August 2020

Die roboterassistierte Thoraxchirurgie gewinnt in den letzten Jahren auch in Europa zunehmend an Bedeutung. Aufgrund des begrenzten Raumes und der engen Lagebeziehung wichtiger anatomischer Strukturen stellt die minimalinvasive Mediastinalchirurgie eine besondere Herausforderung an den Operateur dar. Aufgrund der hochauflösenden 3-D-Bildgebung, präzisen Instrumentenführung mit hoher Beweglichkeit auf kleinstem Raum eröffnet die robotisch assistierte Thoraxchirurgie im Mediastinum neue minimalinvasive Möglichkeiten und kann die Sicherheit und Radikalität bei der onkologischen Resektion von Mediastinaltumoren verbessern. Dieser Artikel gibt einen Überblick über den aktuellen Stand der roboterassistierten Mediastinalchirurgie und fasst zentrale Aspekte der Indikationsstellung, Operationsplanung und Durchführung der roboterassistierten Mediastinaltumorresektion zusammen.
Morbidity in Newborns Readmitted Into a Hospital After Discharge From a Maternity Unit During the First 28 Days of Their Lives – Results From the Rhine-Main Area, Germany
Authors: Anagnostou Anastasia , Schrod Lothar , Jochim Judith , Enenkel Jürgen , Krill Winfried , Schlößer Rolf Lambert
Published: August 2020

Background The neonatal period can be associated with a multitude of
medical and social problems. Little is known about the reasons that lead to
neonatal readmissions in a pediatric hospital and their individual outcomes.

Objective To record the diagnosis of neonatal admissions in a pediatric
hospital after discharge from a maternity unit. Predictive parameters are to be
identified and a possible trend over the years is to be examined.

Methods The medical history of newborns admitted to a pediatric hospital
in the Rhine-Main area from 01/01/2004 to
31/12/2013 was retrospectively analyzed based on provided
medical files.

Results The data of 2851 newborns was recorded. 72% of the
patients were delivered by vaginal birth. During the period under examination,
there was a certain fluctuation although no significant trend in the number of
admissions per year (p=0.062). The most frequent primary diagnoses were
jaundice (27%), newborn infection (12.4%), and feeding problems
(12.3%). Exclusively breastfed newborns had fewer feeding problems than
newborns with a mixed or purely formula diets (p < 0.001).

Conclusions The results of this study showed that the hospital
readmissions of newborns throughout the years did not increase. Unfortunately,
owing to the retrospective character of the study, it is not possible to make a
clear statement as to whether hospitalization can be prevented with more
intensive preventative measures. A prospective study on this matter is being
planned.
Oceanographic influence on coastal zooplankton assemblages at three IMOS National Reference Stations in Western Australia
Authors: McCosker Erin , Davies Claire H. , Beckley Lynnath E.
Published: August 2020

Knowledge about the coastal zooplankton of the south-eastern Indian Ocean is limited, with few studies having compared assemblages across the latitudinal range of the western seaboard of Australia. The dominant oceanographic feature in this region is the Leeuwin Current, which transports warm, lower-salinity, tropical waters southward along the shelf-edge. This study examined data collected by Australia’s Integrated Marine Observing System at three coastal National Reference Stations located at 22°S 114°E, 32°S 115°E and 34°S 122°E. Spatial and temporal patterns in zooplankton abundance, composition and diversity were investigated, and differences in assemblage structure, particularly with respect to copepods, were related to oceanographic conditions. Clear dissimilarities among copepod assemblages were observed, becoming weaker in winter owing to enhanced connectivity of species driven by alongshore and cross-shelf transport in the Leeuwin Current. Both physical and biogeochemical factors were significant in structuring copepod assemblages, with seawater density, incorporating temperature and salinity, exerting the greatest influence. The results suggest that both broad-scale latitudinal gradients and mesoscale events contribute to variation in zooplankton assemblages in these waters. This study provides the first detailed comparison of zooplankton assemblages among the north-west, south-west and southern coastal waters of Western Australia, and enhances understanding of the processes influencing zooplankton distribution and structure.
Regional variation in habitat matrix determines movement metrics in Baudin’s cockatoos in southwest Western Australia
Authors: Rycken Sam , Shephard Jill M. , Yeap Lian , Vaughan-Higgins Rebecca , Page Manda , Dawson Rick , Smith Karen , Mawson Peter R. , Warren Kristin S.
Published: August 2020

Abstract ContextThe Baudin’s cockatoo is one of three black cockatoo species endemic to Western Australia and is listed as Endangered by state and federal governments. Although there is a Recovery Plan in place for this species, conservation efforts are hindered by gaps in knowledge regarding the species movement ecology. AimsTo identify key foraging and roosting habitat for Baudin’s cockatoos and to determine differences in flock movements, including the spatial extent of movement, in Urban, Peri-urban and Forest regions using telemetry data. MethodsWild Baudin’s cockatoos that had been injured and undergone rehabilitation were equipped with satellite PTT (platform transmitter terminal) and GPS tags and released back into wild flocks. The study birds, and the flocks into which they integrated, were tracked in the field to collect telemetry and observational data. Satellite data were used to define the types of movement behaviour (resident, ranging, migratory), and GPS data were analysed to determine key foraging and roosting habitat, and to calculate home range area estimates. Key resultsThere was a significant difference in flock movement between the Urban/Peri-urban regions and the Forest region in terms of daily distances moved and distances between roosts, with these parameters being far greater for the Forest region. Additionally, flock sizes were larger in the Forest region compared with the Urban and Peri-urban regions. In Urban and Peri-urban regions, key habitat comprised remnant vegetation in urban green space (nature reserves, parks and private property), and roadside and riparian vegetation, which served as movement corridors in the landscape. ConclusionsThe research shows that it is important to maintain vegetation connectivity in the landscape. This enables Baudin’s cockatoos to utilise key patches of remnant vegetation in their non-breeding wintering grounds in Urban and Peri-urban regions of the Perth Peel Coastal Plain. Further research on the movement ecology of Baudin’s cockatoos should focus on habitat suitability modelling, which, in combination with the identified key habitat sites, will benefit the decision-making process in relation to conservation management of this endangered black cockatoo species. ImplicationsThis research has benefited the conservation management of Baudin’s cockatoos by providing information on key habitat through satellite tracking and outlining the importance of the connective features of remnant vegetation. We advocate for further telemetry studies combined with habitat suitability modelling to preserve the necessary habitat for the persistence of this species in the Western Australian landscape.
On the translation of Japanese politeness into Cantonese
Authors: Shih Pei Chun
Published: August 2020

This paper utilizes the reconstructive nature of translation to examine how formal (neutral and honorific) and
plain forms of Japanese are represented in Cantonese dubbing with the aim of exploring some common politeness features of
Cantonese that the translator adopts in order to compensate for the difference between the two languages. Address terms that do
not exist in the Japanese original, for example deferential terms and kinship terms, are inserted in Cantonese dubbing to
represent different speech levels of Japanese. This paper further argues that such inserted address terms help to realize
politeness by either recognizing the superior status of addressees or by including an addressee as an in-group member. Some cases
of insertions also suggest strategic adoption of address terms in Cantonese. In addition to observing social norms and addressing
each other appropriately, Cantonese speakers can also exploit address terms strategically to achieve specific pragmatic goals.
The Wheel of Time
Authors: Li Heng , Cao Yu
Published: August 2020

Previous research suggests that both patterns in orthography and cultural-specific associations of space-time affect how
people map space onto time. In the current study, we focused on Chinese Buddhists, an understudied population, investigating how religious
experiences influence their mental representations of time. Results showed that Chinese Buddhists could represent time spatially
corresponding to left-to-right, right-to-left and top-to-bottom orientations in their religious scripts. Specifically, they associated
earlier events with the starting point of the reading and later times with the endpoint. We also found that Chinese Buddhists were more
likely to represent time in a clockwise way than Chinese atheists. This is because Buddhism regards time as cyclic and consisting of
repeating ages (i.e. Wheel of Time). Taken together, we provide first psychological evidence that Chinese Buddhists’ spatial representations
of time are different from atheists’, due to their religious experiences, namely, both the reading direction in Buddhist texts and Buddhist
concepts of time.
An extended cellular automata model with modified floor field for evacuation*
Authors: Qin Da-Hui , Duan Yun-Fei , Cheng Dong , Su Ming-Zhu , Shao Yong-Bo
Published: August 2020

The floor field model has been widely used in evacuation simulation research based on cellular automata model. However, conventional methods of setting floor field will lead to highly insufficient utilization of the exit area when people gather on one side of the exit. In this study, an extended cellular automata model with modified floor field is proposed to solve this problem. Additionally, a congestion judgment mechanism is integrated in our model, whereby people can synthetically judge the degree of congestion and distance in front of them to determine whether they need to change another exit to evacuate or not. We contrasted the simulation results of the conventional floor field model, the extended model proposed in this paper, and Pathfinder software in a same scenario. It is demonstrated that this extended model can ameliorate the problem of insufficient utilization of the exit area and the trajectory of pedestrian movement and the crowd shape of pedestrians in front of exit in this new model are more realistic than those of the other two models. The findings have implications for modeling pedestrian evacuation.
Giant anisotropy of magnetic damping and significant in-plane uniaxial magnetic anisotropy in amorphous Co40Fe40B20 films on GaAs(001)*
Authors: Wang Ji , Tu Hong-Qing , Liang Jian , Zhai Ya , Liu Ruo-Bai , Yuan Yuan , Huang Lin-Ao , Liu Tian-Yu , Liu Bo , Meng Hao , You Biao , Zhang Wei , Xu Yong-Bing , Du Jun
Published: August 2020

Tuning magnetic damping constant in dedicated spintronic devices has important scientific and technological implications. Here we report on anisotropic damping in various compositional amorphous CoFeB films grown on GaAs(001) substrates. Measured by a vector network analyzer-ferromagnetic resonance (VNA-FMR) equipment, a giant magnetic damping anisotropy of 385%, i.e., the damping constant increases by about four times, is observed in a 10-nm-thick Co40Fe40B20 film when its magnetization rotates from easy axis to hard axis, accompanied by a large and pure in-plane uniaxial magnetic anisotropy (UMA) with its anisotropic field of about 450 Oe. The distinct damping anisotropy is mainly resulted from anisotropic two-magnon-scattering induced by the interface between the ferromagnetic layer and the substrate, which also generates a significant UMA in the film plane.
Tail-structure regulated phase behaviors of a lipid bilayer*
Authors: Li Wenwen , Lin Zhao , Yuan Bing , Yang Kai
Published: August 2020

Lateral heterogeneity of a cell membrane, including the formation of lipid raft-like clusters and the inter-leaflet coupling of specific phase domains, is crucial for cellular functions such as membrane trafficking and transmembrane signaling. However, the wide diversity in lipid species and the consequent complexity in lipid–lipid interplays hinder our understanding of the underlying mechanism. In this work, with coarse-grained molecular dynamics simulations, the effect of lipid tail structures on the phase behavior of a model ternary lipid membrane was systematically explored. A serial of 27 lipid membrane systems consisting of saturated, unsaturated lipids, and cholesterol (Chol) molecules, at a fixed molar ratio of 4:4:2 while varying in lipid structures including tail length, unsaturation degree, and/or position of unsaturated atoms, were constructed. These structural factors were found to exert sophisticated influences on packing states of the constituent molecules, especially Chol, in a bilayer, and modulate the complicated entropy–enthalpy competition of the membrane system accordingly. Specifically, an appropriate difference in effective tail length and distinct feature of the tail ends between the saturated and unsaturated lipid compositions promised an enhanced phase separation of the membrane into the Chol-rich Lo and Chol-poor Ld phase domains, with a full inter-leaflet coupling of each domain. Our results provide insights into the lipid organizations and segregations of the cellular plasma membrane.
Effects of Re, Ta, andWin [110] (001) dislocation core of γ/γ′ interface to Ni-based superalloys: First-principles study*
Authors: Zhu Chuanxi , Yu Tao
Published: August 2020

The strengthening effects of alloying elements Re, Ta, and W in the [110] (001) dislocation core of the γ / γ′ interface are studied by first-principles calculations. From the level of energy the substitution formation energies and the migration energies of alloying elements are computed and from the level of electron the differential charge density (DCD) and the partial density of states (PDOSs) are computed. Alloying elements above are found to tend to substitute for Al sites γ′ phase by analyzing the substitution formation energy. The calculation results for the migration energies of alloying elements indicate that the stability of the [110] (001) dislocation core is enhanced by adding Ta, W, and Re and the strengthening effect of Re is the strongest. Our results agree with the relevant experiments. The electronic structure analysis indicates that the electronic interaction between Re-nearest neighbor (NN) Ni is the strongest. The reason why the doped atoms have different strengthening effects in the [110] (001) dislocation core is explained at the level of electron.
Wireless graphene-enabled wearable temperature sensor
Authors: Kovalska Evgeniya , Baldycheva Anna , Somov Andrey
Published: August 2020

E-textile is an emerging technology which takes the advantages of material science, electronic engineering and wireless communications. We present a pilot study on smart textile system. Our study aims at developing a graphene temperature sensor and its interfacing with a commercial wireless sensor node providing the graphene sensor with processing and wireless communication capabilities. Flexible planar structure sensor was fabricated using CVD-processed single-layer graphene following its transfer to the polyvinyl chloride substrate by hot lamination method. For calibrating the graphene temperature sensor we connect it in series with a calibrated resistor and to the calibrated power source (battery). Afterwards we measure the sensor resistance via the analogue-to-digital converter of wireless sensor node, process the data and send it to the user over wireless channel.
Applied computing approach calculations for g-Factor and HFS calculations of Light Ions
Authors: Berseneva E. , Baldycheva A. , Harman Z. , Keitel C.H. , Tupitsyn I.I.
Published: August 2020

Electron correlation effects on the bound-electron g-factor and hyperfine structure in highly charged ions are calculated by a combination of perturbation theory to leading order in 1/Z, with Z being the atomic number, and a large-scale relativistic configuration interaction method. Our results for lithiumlike ions improve the accuracy of earlier calculations by one or two digits.
The formation of a sensitive structure of a contact lens sensor
Authors: Panfilova E V , Mozer K V , Ibragimov A R
Published: August 2020

Smart photonic crystal structures have attracted great attention in various areas of life. For medicine application smart photonic crystal films is promising as highly sensitive elements of contact lenses for monitoring the lacrimal glucose and intraocular pressure. To obtain structures with desired properties, the process parameters must be controllable, and the properties of structures must be reproducible and satisfy specified requirements. This article describes the controllable electrodeposition method and equipment for producing polystyrene opal photonic crystal films onto the surface of hydrogel contact lenses. We obtained quality three-dimensional ordered films with reproducible properties.
6th International Week of Science, Technology and Innovation
Authors: Rojas-Suárez J P , Velásquez-Pérez T , Sandoval-Amador A , Dueñas Ramírez L M , V-Niño E D
Published: August 2020

The 6th International Week of Science, Technology and Innovation (6th IWSTI), which took place from 19 to 22 November 2019, in the city of San José de Cúcuta, Colombia, and was organized by the “Universidad Francisco de Paula Santander”, San José de Cúcuta” and “Seccional Ocaña”.

This event was aimed at the academic and scientific community and the productive sectors of the region. The objective of the 6 edition of the International Week of Science, Technology, and Innovation was to disseminate the advances in research and extension of national and international institutions, through seedbeds and research groups, promoting the participation of the productive sectors in research, extension, and technological development and innovation activities, which contribute to the strengthening of the University-Business-Government relationship.

List of Organizing Committee, International Scientific Committee, National Scientific Committee, Logistics Committee and Sponsors are available in this pdf.
Post-consumption foamed polystyrene coatings for surface tension modification
Authors: Bustos N , Gamarra C , Ponton D , Roa M
Published: August 2020

Foamed polystyrene, commercially known as Icopor, occupies a very important place in the transport systems, and conservation of freight and food, but it is also one of the main polymeric pollutants, due to its low biodegradability, and low reuse. Polystyrene has in its structure aromatic and aliphatic functional groups, which have a high hydrophobicity, which makes them candidates as modifiers of permeability and surface properties, although for this purpose the implementation of solvents is also required. In the following work, polystyrene residues for domestic and food use were used to obtain coatings, which allow surface tension to be modified, on surfaces with high water permeability. For this purpose, the polymeric residue was dissolved in organic type solvents, generating a varnish, which was used to coat the study surface, from which the surface tension with respect to water was previously known by analysing the contact angle; to be compared with those obtained after coating, resulting in an increase in the contact angle, which indicates an increase in surface tension, conferred on the new surface hydrophobicity.
Evolution of ubiquitous computing
Authors: Velásquez-Pérez T , Camargo-Pérez J A , Rodríguez-Chinchilla A M
Published: August 2020

Ubiquitous computing understood as the integration of the machine to man is applied in interactive environments where tools such as mobile devices produce this continuous change. This article presents an analysis on the evolution of the internet of things, based on the research found on the science websites, whose objective was based on knowing in depth the conceptual evolution of the internet of things and the context in which it has developed. It is chosen to use a methodology of science mapping that allowed an analysis of scientific productions through cluster analysis and multidimensional scaling, bibliometrics is a scientific discipline that is based on the search for statistically regular behaviors over time in the different elements related to scientific production. A conglomerate of articles was found that were adjusted to the search equations used in the science website, which within the analysis carried out can be used as a reference for other researchers in their research, which that allows enriching the field of research discussed here, this research is important insofar as it allowed to imply in a greater degree of depth the IoT and its evolution over the years.
Physicochemical and statistical analysis of a dairy production
Authors: Hurtado-Lugo N , Rincon A , Ceron-Muñoz M
Published: August 2020

The objective of this study to evaluate by physicochemical and statistical analysis the compositional quality of milk-based on the constituents of fat, protein, and non-fat solids in dairy cattle located in the “Ocaña, Norte de Santander, Colombia”. Having a total of 905 dairy controls in 15 females with double milking/day throughout breastfeeding, the descriptive statistics were subsequently calculated. The average values for the percentage of fat, protein, and non-fat solids were 4.1%, 2.9%, and 8.2% with a standard deviation of 0.957, 0.210, and 0.555 respectively. The physical and chemical components of milk were found in the range stipulated by studies focused on milk yield and quality. On the other hand, it is concluded that the variation obtained in the constituents, is within the expected for the region and the species. It is also suggested that the variations of these constituents may be associated with factors such as the stage of lactation and quality of forages in winter and summer.
Experimental determination of thermal conductivity as physical property of organic and recyclable materials
Authors: Perez-Rangel N Y , Arévalo-Ruedas J H , Florez-Solano E
Published: August 2020

There are different types of traditional materials for insulation in different processes such as: clay, limestone, ceramic foams, among others, used mainly in furnaces and buildings, whose function is to reduce heat and acoustic noise transfer through the structure on which they are installed. Alternatives for insulation with reusable and organic materials are currently being sought. In this work, the physical property of the thermal conductivity of materials such as quartz, glass, bone, and coconut shells were analyzed in order to compare their thermal conductivity measured experimentally with respect to that reported theoretically, and determine if they are suitable for use in the market and also to have a foundation that allows subsequent processes to mix them, giving way to new insulating or refractory materials with better physical properties.
Soil characterization through remote acquisition of electromagnetic radiation
Authors: Pelaez D A , Gualdron O E , Torres I
Published: August 2020

In order to promote agronomic activity and generate a new tool that generates indicators and contributes to decision-making and optimization of resources for agribusiness, the objective of the research is focused on characterizing soils with productive potential by means of the normalized difference vegetation index using multispectral images, a new information acquisition system is provided through photometry that allows establishing important characteristics in the sampled surface, This uses a multispectral system composed mainly of an optical sensor sensitive to electromagnetic radiation reflected by plant material, mainly in wavelengths equal to 475 nm with a bandwidth of 10 nm and 840 nm with a bandwidth of 40 nm, this system is integrated into an unmanned aerial vehicle that allows remote acquisition in visible and non-visible light spectrum ranges, the acquisition of images was carried out at heights between 100 meters and 200 meters to obtain a resolution of 80 mm per pixel, obtaining as a result a relationship between the wavelength levels and the main characteristics of the sampled soils.
Pedagogical practices of physics teachers from the Catatumbo region, Colombia
Authors: Gallardo Pérez H J , Vergel Ortega M , Villamizar Jaimes D
Published: August 2020

Pedagogical practice allows teachers to focus their attention on three types of knowledge: disciplinary knowledge: what do I know, pedagogical knowledge: how do I communicate what I know, and academic knowledge: how do I transform myself with what I know? Thus, the teacher has the capacity to transform not only his or her students, but to transform himself or herself in the process. In this sense, the research aims to characterize the pedagogical practice of physics teachers in educational institutions located in the “Catatumbo, Colombia”, a region characterized by high levels of violence and very specific social situations; it also aims to determine the influence of training at the master’s level of the Francisco de Paula Santander University on teachers working in the area of physics. The research, framed in the mixed paradigm, allows the realization of univariate and multivariate analysis of variables inherent to the process of training and professional action of master teachers, as well as the categorization of their experiences resulting from the application of knowledge obtained throughout their studies in their professional practice and training in different areas of knowledge, emphasizing the practices, laboratories and teaching strategies used in the training of students by physics teachers.
Performance Evaluation of Second-Throat Diffuser for High Altitude Test facility
Authors: Qian Hengxiao , Zhong Wei , Li Zhao , Li Pan , He Shilong
Published: August 2020

Aimed at the improvement of ability of the high altitude test (HAT) facility for rocket engine, a new designed secondary-throat diffuser with ejection of low total pressure and supersonic cold air is proposed. The main structural characteristic of the new-designed diffuser is that: a groove is added to the start of the secondary throat of diffuser, and the supersonic cold air with low total pressure is ejected into diffuser to form the gas film, which leads to a reduction of the wall temperature and thermal load of the new-designed diffuser, and an improvement of the ability of diffuser holding shock train. The effects of cold air on flow characteristics and performance of diffuser are numerically investigated in detail under different conditions including total pressure and Mach number. The results show that the wall temperature along the diffuser increases with an increase of Mach number, and decreases with an increase of total pressure; with an increase of Mach number, the starting position of pressure rise moves upstream to the inlet of diffuser; and with an increase of total pressure, the starting position of pressure rise moves downstream to the end of diffuser.
Study on the optimization of missile take off mass and its influence on aerodynamic parameters
Authors: Li Jun , Qi Wei , Gong Haoran , Zhang Yang
Published: August 2020

Aiming at the problem of optimal design of take-off quality in the process of missile overall design, on the basis of establishing the optimization model of missile take-off quality, three different optimization algorithms are used to optimize the calculation of missile take-off quality, by comparing the effects of the three algorithms on the takeoff mass optimization and aerodynamic parameters, the models and algorithms for different types of missiles are obtained.
Comprehensive Fuzzy Evaluation for Simulated Training of Aerial Mechanist
Authors: Li He , Yu Jie , Yu Dehui , Sun Jing , Zhang Kai
Published: August 2020

Performance evaluation is an important part of simulated training, and also a challenging project in the development of simulators for aerial mechanist training. In this paper, the evaluation method is explained in detail, and then the evaluation model is put forward, and finally the application of comprehensive fuzzy evaluation is discussed in this paper.
New Understanding of the Retention Mechanism of “Residual Oil in the Form of Oil Droplets (or Oil Column)”
Authors: Dai Jinyou , Lin Lixin
Published: August 2020

Based on the oil-water two-phase liquid flow model, with equal-viscosity and water-wet unequal-diameter parallel channels, the previous researches on the retention mechanism of “residual oil in the form of oil droplets or oil column” during water flooding, and they stated that “residual oil in the form of oil droplets (or oil column)”can be retained in both large and small channels. Re-examination of the model shows that “residual oil in the form of oil droplets (or oil column)” cannot be retained in large channels, but only in small channels. By changing the wettability and oil-water viscosity (variable viscosity) of this model, the small channel retention characteristics of “residual oil in the form of oil droplets (or oil column)” remain unchanged. This research shows that: (1) When the oil-water phase flows in the unequal-diameter parallel channel model, the flow velocity of the large channel is always greater than the small channel, and the “residual oil in the form of oil droplets (or oil column)” is always retained in the small channel. (2) The retention of small channels of “residual oil in the form of oil droplets (or oil column)” is general, and is not affected by changes in factors such as pressure difference, capillary force, total flow, wettability, and oil-water viscosity ratio.
Thermal modeling and validation for EV battery packs in realistic operation conditions
Authors: Chen Hu , Zhu Linpei , Liu Jing , Xiong Fei , Wei Dan
Published: August 2020

Battery pack is one of the most important components of electrical vehicles (EV). The safety, aging and life of battery packs are significantly related to its thermal behavior. This work concerns with thermal behavior of an EV battery pack for realistic engineering applications. The Bernardi’s heat generation model with the consideration of reversible heat is employed and validated by tests and numerical simulation on battery cells. Then the validated cell model is applied to an EV battery pack with cooling system underneath for the study of thermal behavior in a realistic operation condition, and numerical results are in good agreement with the test results.
Numerical Simulation and Analysis for Aerodynamic Devices of FSAE Racing Car
Authors: Deng Zhaowen , Yu Sijia , Wu Chao
Published: August 2020

Improving the aerodynamic characteristics of racing cars is one of the important means to improve the performance of FSAE.This paper completed the FSAE car body and aerodynamics device design and development, based on the CFD technology in the car’s aerodynamic characteristics are studied.Through the analysis of the aerodynamic characteristics of the car body with and without aerodynamic devices, and the comparative analysis of airflow pressure and velocity distribution around the car body and aerodynamic devices, the simulation results show that the aerodynamic devices effectively improve the aerodynamic characteristics of the car, and better improve the control stability and driving safety of the car.
Experimental and numerical study on the free surface vortex of a mixed flow pump device model
Authors: Zhang Zilong , Liu Houlin , Wang Yong
Published: August 2020

Because of the advantages of small installation space, good cavitation performance, low cost and easy maintenance, the open channel pump station is widely used in agricultural production, flood control and ecological construction. In the process of operation, large-scale vortices such as wall vortex, bottom vortex and surface vortex easily appear. Under special working conditions, the head and efficiency of the pump station will be reduced, cavitation will occur at the blades, shafting will move, and the unit will vibrate, which will reduce the service life and safety of the pump station. In this paper, the head, efficiency, flow characteristic and free surface vortex of a mixed flow pump device model in pumping station under different water level and flowrates are studied numerically and experimentally, providing experience and theoretical reference for the design of the pumping station.
Analysis of Elbow Effect on the High Pressure Gas Pipe
Authors: Zhang Jianhua , Huang Haifeng , Hu Kun , Zhang Ping
Published: August 2020

For the problem of the pressure drop loss and the equivalent length calculation of elbows in submarine high pressure pipelines, the flow processes of ultra-high pressure gas in 90° elbows were numerically simulated by the way of CFD. The inner flow area was meshed with structured hexahedral grid, and by means of the numerical solution to deal with the RANS equations closed by RNG k-ε turbulence model, the flow field characteristics inside the pipe was studied, and the pressure distribution was obtained. The calculated results are consistent with the numerical simulation and model experiment results carried out by other scholars. Simulation results show that the total pressure loss of the pipe will be increased greatly due to the partial pressure loss caused by elbows. Besides, the feasibility and availability of simulating the flow characteristics of the ultra-high pressure gas inside the elbows by RNG k-ϵ turbulence model were verified.
Research on Calculation of Thermal Resistance of Water-Cooling Radiator of Cooling Tower of Thermal Power Plant Based on Fluid Software Fluent
Authors: Zhang Peng
Published: August 2020

This paper introduces the method of calculating the thermal resistance and thermal resistance of high-power water-cooled radiators in cooling towers of thermal power plants using computational fluid software (CDF) Fluent. By solving the three-dimensional unsteady flow field and thermal field, the thermal resistance and thermal resistance value of the water cooling radiator of the cooling tower of the thermal power plant under different flow rates are calculated, which provides the temperature calculation for the steady state and dynamic process of the high-power inverter in accordance with.
Ever-increasing agricultural land and water productivity: a global multi-crop analysis
Authors: Tuninetti Marta , Ridolfi Luca , Laio Francesco
Published: August 2020

Producing more nutritious food with less resources, while preserving the natural ecosystems, is a key challenge of our society. In this paper we propose a macronutrient-based indicator of productivity, the nutrient land productivity (NLP), to measure the amount of calories, proteins, and fats produced per hectare of cropland. Over the period 1961−2016, we find that the global NLP has increased by 2.7–2.9% per year for calories and proteins, and between 2.1 and 4.6% for fats. However, such rates exhibit significant spatial patterns throughout the world depending on whether farmers adopted intensification (e.g. Eastern and South Asia, North America) or extensification (e.g. Sub-Saharan Africa) practices to boost nutrients production. Our outcomes, based on a production basket including 144 crops, show that cereals and pulses cultivations have been dominated by intensification practices coupled with a stable or decreasing harvested area. Conversely, for fruits and nuts cultivations extensification prevailed over intensification, while for oil crops most cultivations experienced a coupled action of the two practises. Finally, by coupling the NLP indicator with its nutrient water productivity (NWP) counterpart, we find that NWP has mainly changed following land patterns, with the exception of locations having undergone significant crop substitutions, namely from less toward more water demanding crops. Indeed, the transition toward perennial crops has increased the evapotranspiration demand over cultivated land by 14% on a global average.
Reconciling forest profitability and biodiversity conservation under disturbance risk: the role of forest management and salvage logging
Authors: Augustynczik Andrey L D , Asbeck Thomas , Basile Marco , Jonker Marlotte , Knuff Anna , Yousefpour Rasoul , Hanewinkel Marc
Published: August 2020

Forest management and disturbances are among the main drivers of changes in forest dynamics in temperate ecosystems. To promote and maintain forest multifunctionality and species persistence in the landscape, it is critical that the interactions between these factors and forest biodiversity are disentangled. Still, the relationships between disturbances and forest management are poorly understood and may hinder an adequate planning of management and conservation actions in these forests. Here we address this issue via a coupled ecological-economic modeling system under different climate change scenarios. We employed data from a large-scale field-based research in southwestern Germany, in combination with a climate-sensitive forest growth model. Thereby, we quantified changes in multiple biodiversity indicators (including richness of birds, bats and flying insect orders) and tree microhabitats (TreMs) in the face of disturbance and management interventions. Our results show that windstorms may cause economic damage in managed forests, but at the same time improve biodiversity indicators in these areas. Salvage logging, however, may dampen these positive impacts for the majority of indicators considered. Moreover, management solutions targeting at wind risk mitigation may be detrimental to some taxa (e.g. forest birds) but still performed better than the business-as-usual management, in terms of the biodiversity indicators applied. We conclude that considering disturbance impacts on forest dynamics will be key to maintain the sustainability in the use of forest resources and support species persistence in temperate forest landscapes.
Hearing the shape of inequivalent spin structures and exotic Dirac operators
Authors: da Rocha R , Tomaz A A
Published: August 2020

Exotic spinor fields arise from inequivalent spin structures on non-trivial topological manifolds, M. This induces an additional term in the Dirac operator, defined by the cohomology group

H

1

(

M
,

Z

2

)

that rules a

C

̌

ech cohomology class. This formalism is extended for manifolds of any finite dimension, endowed with a metric of arbitrary signature. The exotic corrections to heat kernel coefficients, relating spectral properties of exotic Dirac operators to the geometric invariants of M, are derived and scrutinized.
Sequences of lower bounds for entropic uncertainty relations from bistochastic maps
Authors: Giorda Paolo
Published: August 2020

Given two orthonormal bases

A

and

B

, the basic form of the entropic uncertainty principle is stated in terms of the sum of the Shannon entropies of the probabilities of measuring

A

and

B

onto a given quantum state. State independent lower bounds for this sum encapsulate the degree of incompatibility of the observables diagonal in the

A

and

B

bases, and are usually derived by extracting as much information as possible from the unitary operator U connecting the two bases. Here we show a strategy to derive sequences of lower bounds based on alternating sequences of measurements onto

A

and

B

. The problem can be mapped into the multiple application of bistochastic processes that can be described by the powers of the unistochastic matrices directly derivable from U. By means of several examples we study the applicability of the method. The results obtained show that the strategy can allow for an advantage both in the pure state and in the mixed state scenario. The sequence of lower bounds is obtained with resources which are polynomial in the dimension of the underlying Hilbert space, and it is thus suitable for studying high dimensional cases.