Miracle-dz/UniFAR-FTUs huggingface dataset:
Fatigue in Textile Fibers

A series of experiments was conducted to study the effect of stroke on the performance of various types of fiber (one acrylic, two of nylon, two of Dacron, and one viscose rayon) under cyclic tension. It was found in the acrylic sample at a particular frequency, 250 cycles/min, that the distribution changes from unimodal to bimodal as the stroke is raised from 2.0% to 4.1%, and that at the latter stroke the second (new) mode is dominant The bimodal distribution is interpreted as reflecting two different mechamisms of fatigue rupture. The distributions of lifetimes for the other five samples, in general, were found to conform well to a ummodal pattern. with the exception of data for a relatively narrow range of strokes, where there are indications that the distributions may be bimodal. Because the two modes were not clearly separable in the data on these five samples. the distributions were taken as being unimodal, and computations were undertaken to obtain, for various strokes, estimates of the parameters of the third asymptotic distribution. Trends in one of these parameters for Dacron 52, minimum life, indicate that there is apparently a wider scatter in lifetimes associated with lower strokes. The conclusion is reached that a valid judgment of the relative fatigue performance of various fiber samples requires a knowledge of the probability of survival under conditions permitting relatively long lifetimes. The probability of survival to various times at different strokes was calculated for the acrylic sample. The plotted results show that the probabilities and survival times (lifetimes) increase sharply when the stroke is reduced below the elastic limit. Plots of stroke vs. average number of cycles to rupture, for all six samples, show that, on the average, Dacron 420 performed the best, in that it withstood the highest stroke to the highest average number of cycles. Average lifetimes ranged from 10 to 10 6 cycles. It was found to be experimentally impractical to attempt to determine an endurance limit with respect to stroke, for any of the samples An alternative criterion of fatigue performance is proposed.
Energy Transfers in Fluid Flows

Turbulence remains an unsolved problem due to the complex nonlinear interactions among a large number of multiscale structures. For hydrodynamic turbulence, Kolmogorov’s theory provides quantitative measures of energy contents of the fluid structures and energy flux. However, this theory based on real space description does not quantify various scale-by-scale energy transfers. In addition, generalisations of Kolmogorov’s theory to more complex system— magnetohydrodynamic and buoyancy-driven turbulence, anisotropic flows, etc.—are quite involved. Fortunately, spectral or Fourier space description, which is the theme of this monograph, overcomes some of these deficiencies.
Evaluation of Roots and Canal Systems of Mandibular First Molars in a Vietnamese Subpopulation Using Cone-Beam Computed Tomography

Objectives: The aim of this study is to determine the prevalence of the first lower molars that have two roots or three roots and the number of the root canals of the mandibular first molars in the Vietnamese subpopulation using cone-beam computed tomography (CBCT). Materials and Methods: The study was conducted on 166 patients who had CBCT as indicated by dentists in Nguyen Trai Dental CT Center, Ho Chi Minh City using the Picasso Trio (Ewoo Vatech, Korea). The number of root canals of the first lower molars was examined by moving cross-sectional slices from the pulpal floor to the apex. The orifices, middle thirds, and apical thirds of the canals of the first lower molar were observed, and the root canals of each root of the mandibular first molars were observed in three planes. Results: The prevalence of two, three, and four root canals of the mandibular first molars was 4.5%, 66.8%, and 28.9%, respectively. For the distal roots of these molars, a classification of Vertucci type I was the most common at a rate of 80.8%–97.6%. Whenever these teeth had three roots, a Vertucci type I was the classification of 100% of distolingual roots. Conclusion: Majority of the mandibular first molars has two roots and three canals. CBCT is appropriate equipment useful in investigating the complex root canal morphology of human teeth.
A Regional Scale‐Invariant Extreme Value Model of Rainfall Intensity‐Duration‐Area‐Frequency Relationships

We propose in this article a regional study of intensity‐duration‐area‐frequency (IDAF) relationships of annual rainfall maxima in southern France. For this we develop a regional extreme value IDAF model based on space‐time scale invariance hypotheses. The model allows us to link the statistical distributions of rainfall maxima over any duration and area. It provides in particular an analytical expression of the areal reduction factor, which expresses how the statistical distribution of rainfall maxima changes as the area increases, for any fixed duration. It also provides an analytical expression of areal return level for the continuum of area and duration. The model is applied to radar reanalysis data covering a 13,000‐km2 region of southern France featuring contrasted rainfall regimes (2008–2015). We estimate the IDAF relationships centered on any radar pixel of the region in the range 3–48 hr and 1–2,025 km2. We obtain in particular a spatial distribution of the areal reduction factor, which allows us to distinguish different rainfall regimes in the region. The overall IDAF model provides also a regional quantification of areal rainfall risk by allowing the computation of rainfall return level maps for any area and duration in the applicable range. Despite inevitable sampling issues due to the shortness of the data sample, we highlight important differences in the spatial distribution of areal rainfall risk depending on the area and duration, illustrating that a comprehensive storm risk evaluation should consider the continuum of area and duration rather than arbitrarily predefined ones.
Dielectric Behaviour of Pure and Dye Doped Nematic Liquid Crystal BKS/B07

The dielectric properties of pure nematic liquid crystal (BKS/B07) and dye doped (Rhodamine B and Anthraquinone) nematic liquid crystal have been investigated in a wide frequency range of 1 kHz to 10 MHz through the dielectric spectroscopic method at varying temperature. In addition to this optical transmittance and textures of the samples have also been observed with a polarizing microscope.
Climate-induced range expansions of marine fauna into the Arctic – what is the most likely colonisation route?

As a result of climate change, the Arctic faunas of the Northeast Atlantic have begun to shift in an Atlantic direction. One system exposed to such a change is the Northeast Greenland (NEG) Shelf. However, the colonisation route taken by boreal fauna to the NEG shelf is unknown. This knowledge is essential to predict to what extent boreal fauna will dominate Arctic habitats, and alter ecosystems in the future. For the species under study here, colonisation is possible from either the Barents Sea via a northern route, or via southern expansion from Iceland and Jan Mayen Island. Here, we used microsatellite markers and established reference population genetic data from Atlantic cod (Gadus morhua), beaked redfish (Sebastes mentella) and deep-sea shrimp (Pandalus borealis) to determine the most likely origin of specimens of these species recently collected at the NEG shelf. We demonstrate that all three species originate from the Barents Sea, and suggest that a likely colonisation route is via advection across the Fram Strait. Our results show that the species composition of Arctic habitats can be shaped by the dispersal of pelagic larvae, and that the fauna of the Barents Sea can project on to adjacent Arctic habitats with unknown consequences to the structure and function of putatively isolated Arctic communities.
New Radiocarbon Dates Show Early Neolithic Date of Flint-Mining and Stone Quarrying in Britain

ABSTRACT New radiocarbon (14C) dates suggest a simultaneous appearance of two technologically and geographically distinct axe production practices in Neolithic Britain; igneous open-air quarries in Great Langdale, Cumbria, and from flint mines in southern England at ~4000–3700 cal BC. In light of the recent evidence that farming was introduced at this time by large-scale immigration from northwest Europe, and that expansion within Britain was extremely rapid, we argue that this synchronicity supports this speed of colonization and reflects a knowledge of complex extraction processes and associated exchange networks already possessed by the immigrant groups; long-range connections developed as colonization rapidly expanded. Although we can model the start of these new extraction activities, it remains difficult to estimate how long significant production activity lasted at these key sites given the nature of the record from which samples could be obtained.
Challenges associated with the climatic interpretation of water stable isotope records from a highly resolved firn core from Adélie Land, coastal Antarctica

Abstract. A new 21.3 m firn core was drilled in 2015 at a coastal Antarctic high-accumulation site in Adélie Land (66.78∘ S; 139.56∘ E, 602 m a.s.l.), named Terre Adélie 192A (TA192A). The mean isotopic values (-19.3‰±3.1 ‰ for δ18O and 5.4 ‰±2.2 ‰ for deuterium excess) are consistent with other coastal Antarctic values. No significant isotope–temperature relationship can be evidenced at any timescale. This rules out a simple interpretation in terms of local temperature. An observed asymmetry in the δ18O seasonal cycle may be explained by the precipitation of air masses coming from the eastern and western sectors in autumn and winter, recorded in the d-excess signal showing outstanding values in austral spring versus autumn. Significant positive trends are observed in the annual d-excess record and local sea ice extent (135–145∘ E) over the period 1998–2014. However, process studies focusing on resulting isotopic compositions and particularly the deuterium excess–δ18O relationship, evidenced as a potential fingerprint of moisture origins, as well as the collection of more isotopic measurements in Adélie Land are needed for an accurate interpretation of our signals.
Analysis of the Variability of the Composition of Sewage Sludge Before and After Drying Treatment – SEM Studies

The aim of the study was to determine the physical and chemical properties of the sewage sludge from “Pomorzany” and “Zdroje” municipal wastewater treatment plants located in Szczecin, Poland. The paper presents the outcomes of SEM observation of dried and stabilized sewage sludge. The research on the obtained materials was conducted using reference methods; the images from a scanning electron microscope were used. The amount of sewage sludge produced with the methods of its management was presented. The technology of sludge management is based on its dehydration up to dry weight content of roughly 20% and then drying in contact dryers up to 90–92% dry weight, separately in both plants. Dried sewage sludge is subsequently burned in mechanical grid boilers at “Pomorzany” WWTP. The analyzed materials were characterized by the pH of 7.90–8.42, dry mass and average organic matter content were 18.949% and 68.903%, respectively. The elements identified in the largest amount on the surface of analyzed materials included calcium, iron, phosphorus, sulphur and silicon. The amount of phosphorus ranging from 1.82 to 3.44% indicates the possibility of using sewage sludge as organic fertilizer product or an alternative source of phosphorus.
New Estimates of Aerosol Direct Radiative Effects and Forcing From A‐Train Satellite Observations

Aerosol direct radiative effects are assessed using multi‐sensor observations from the A‐Train satellite constellation. By leveraging vertical cloud and aerosol information from CloudSat and CALIPSO, this study reports new global estimates of aerosol radiative effects and the component owing to anthropogenic aerosols. We estimate that the global mean aerosol direct radiative effect is −2.40 W/m2 with an error of ± 0.6 W/m2 owing to uncertainties in aerosol type classification and optical depth retrievals. Anthropogenic direct radiative forcing is assessed using new observation‐based aerosol radiative kernels. Anthropogenic aerosols are found to account for 21% of the global radiative effect, or −0.50 ± 0.3 W/m2, mainly from sulfate pollution (−0.54 W/m2) partially offset by absorption from smoke (0.03 W/m2). Uncertainty estimates effectively rule out the possibility that anthropogenic aerosols warm the planet, although strong positive forcing is observed locally where anthropogenic aerosols reside above clouds and bright surfaces.
Greenhouse gas emissions from cranberry fields under irrigation and drainage in Quebec

Agricultural management practices influence the fluxes of greenhouse gases by altering the physical, biological and chemical environment of the soil. Cranberry farming is of particular concern because production takes place on soils with high water tables and the fields are flooded at various times of the year. These conditions initiate reductive processes which lead to the production of greenhouse gases. Weekly dark chamber flux measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) were taken in two farmed cranberry fields in Quebec over the 2012 and 2013 growing seasons. Findings show that commercial cranberry fields are not significant sources of greenhouse gases throughout most of the growing season. CO2, CH4 and N2O fluxes ranged from 1-142 CO2-C m-2 hr-1, -0.01 to 0.04 mg CH4-C m-2 hr-1, and -0.0013 to 0.0013 mg N2O-N m-2 hr-1, respectively. However, when the fields are flooded during the spring melt and for harvest, they become sources of carbon dioxide and methane. Fields that remain flooded for extended periods of time thus emit significantly more greenhouse gases than those which are flooded and drained quickly. %%%%Les pratiques de gestion agricole influencent les flux de gaz a effet de serre (GES) en modifiant l'environnent physique, biologique et chimique du sol. La production de canneberges est particulierement affectee par ces pratiques puisqu'elle a lieu sur des sols avec une nappe phreatique elevee et dont les champs sont inondes a divers moments de l'annee. Ces conditions initient des reactions d'oxydo-reduction qui conduisent a la production de GES. Durant chaque semaine, des mesures du flux de dioxide de carbone (CO2), de methane (CH4) et d'oxyde nitreux (N2O) ont ete prises a l'aide de chambres a air sombres, dans deux champs de canneberges situes pres de la ville de Quebec, pendant la periode de croissance des plantes des saisons 2012 et 2013. Les recherches demontrent que la production commerciale des champs de canneberges n'est pas une source significative de GES. Les flux de CO2, CH4 et N2O varient entre -142 CO2-C m-2 hr-1, -0.01 a 0.04 mg CH4-C m-2 hr-1, et -0.0013 a 0.0013 mg N2O-N m-2 hr-1, respectivement. Cependant, lorsque les champs sont inondes durant le printemps, ainsi que pour la periode des recoltes, ils peuvent devenir des sources de dioxide de carbone et de methane. Les champs qui demeurent inondes pendant de longues periodes de temps emettent alors une plus grande quantite de gaz a effet de serre que ceux qui sont inondes et draines rapidement.
Do Demographic Characteristics of Individuals Associate with their Job Stress Levels? Perspectives from the University of Cape Coast, Ghana.

This study aims to examine the association between individual demographic characteristics with their job stress levels. The study utilized descriptive research design and employed the quantitative approach. The target population comprised employees of the University of Cape Coast, Ghana. Using the convenient sampling approach, 223 employees were selected for the study and data collection was done through a survey questionnaire. The Pearson Chi-Square test was used to test for the association between the study variables. The findings suggested that sex and marital status of respondents have significant association with their job stress levels. However, the study did not find any significant association between levels of job stress and respondents’ age and levels of education.
Impression creep behaviour of tin based lead free solders

Abstract Tin based solders are being considered as substitutes for conventional Pb based analogues. The possibility of solder joint failure during service of electronic packages as a result of creep caused by heating is investigated in the present study by the impression creep of eutectic Sn - 3.5Ag, Sn - 0.7Cu and Sn - 9Zn alloys in the temperature range 303 - 439 K and in the stress range 21 - 148 MPa. The power law stress exponent values vary from 3.5 to 6.5. The activation enthalpy for Sn - 3.5Ag was found to be stress independent with an average value of 41 kJ mol-1. The activation enthalpies for Sn - 0.7Cu and Sn - 9Zn showed moderate stress dependence with zero stress activation enthalpies of 52 and 74 kJ mol-1, respectively. The steady state impression velocity varied linearly with punch diameter for all three alloys. The experimental results support dislocation climb as the rate controlling mechanism.
Production and properties of highly oriented polyoxymethylene by die‐drawing

Highly oriented monofilaments were produced by a high-temperature die-drawing process followed by tensile drawing. It was shown that a successful high-speed process required high-quality melt-extruded rod. The mechanical properties and structure of the die-drawn products were investigated by means of tensile and bending tests, dynamic mechanical measurements, DSC, and X-ray diffraction. The bending modulus and the tensile strength increased with increasing draw ratio. It was also observed that at high draw ratios the γ-dispersion peak in the dynamic mechanical tan δ curve, which is associated with main chain micro-Brownian motion in the amorphous regions, diminishes, implying that these chains become taut. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1268–1278, 2003
A generalized enhanced Fourier law and underlying connections to major frameworks for quasi-ballistic phonon transport

An enhanced Fourier law (EFL) that accounts for quasi-ballistic phonon transport effects in a formulation entirely in terms of physical observables, is derived from the Boltzmann transport equation, assuming a gray population of quasi-ballistic phonon modes. This equation is generalized to an arbitrary phonon population. Other phonon transport models are analyzed in the context of the generalized EFL and connections are made between the generalized EFL and other models, revealing the essential unity of seemingly disparate models reported in the literature.
Impact of the Accuracy of Land Cover Data sets on the Accuracy of Land Cover Change Scenarios in the Mono River Basin, Togo, West Africa

The results reveal CILSS as the most accurate data set with a Kappa coefficient of 68% and an overall accuracy of 83%. CILSS data shows a decrease of savanna and forest whereas an increase of cropland over the period 1975 to 2013. The increase of cropland area of 30.97% from 1975 to 2013 can be related to the increase in population and their food demand, while the losses of forest area and the decrease of savanna are further amplified by using wood as energy sources and the lack of forest management. The three datasets were used to simulate future LULC changes using the Terrset Land Change Modeler. The validation of the model using CILSS data for 2013 showed a quality of 50.94%, it is only 40.04% for ESA and 20.13% for Globeland30. CILSS data was utilized to simulate the LULC distribution for the years 2020 and 2027 because of its satisfactory performances. The results show that a high spatial resolution is not a guarantee of high quality. The results of this study can be used for impact studies and to develop management strategies for mitigating negative effects of land use and land cover change.
On the Marine Energy Resources of Mexico

The Atlantic and Pacific coasts of Mexico offer a variety of marine energy sources for exploitation. Although the Mexican government has made important efforts to reduce its dependence on fossil fuels, national participation in clean energies is still limited in terms of electricity production. This paper presents a practical theoretical assessment of marine energy sources around Mexico, with the aim of identifying potential zones for subsequent, more detailed, technical evaluations and project implementations. The energy sources considered are ocean currents, waves, salinity, and thermal gradients. Using global databases, the percentages of energy availability for the defined thresholds were computed to establish the prospective regions with the most persistent power availability. This approach proved to offer more meaningful information than simple averaged values. Moreover, some environmental and socio-economic factors to be considered for future ocean energy resource assessments in Mexico were also discussed. The results show that the wave energy potential is highest in the northwest of Mexico (~2–10 kW/m for more than 50% of the time), and that there is a constant source of ocean current energy off Quintana Roo state (~32–215 W/m2 for more than 50% of the time). The thermal gradient power is more persistent in the southwest and southeast of the country, where ~100–200 MW can be found 70% of the time. The salinity gradient energy is strongest in the southeast of Mexico. The practical approach presented here can be extended to perform preliminary resources assessments in regions where information is scarce.
Multilevel Hierarchical Caching for Efficient Wireless Video Distribution

ABSTRACT To endure the escalating demand of wireless broadband applications such as high-definition videos, live video streaming in 4G/beyond 4G cellular networks (5G), Device-to-Device (D2D) communication along with D2D caching can serve as a candidate paradigm to enhance spectrum efficiency and Quality of Service (QoS). D2D users can establish a direct connection without routing through evolved NodeB (eNB) and legacy network, by reusing the cellular spectrum, which helps in boosting spectral efficiency. Furthermore, the rapid increase in storage capacity of smart devices can positively drive the network's QoS by caching locally popular videos and disseminating them via D2D communication. With this motivation, we propose a video dissemination architecture with MIX caching, which includes the fusion of evolved packet core (EPC) caching, eNB caching, and additional Friend Node (FN). This paper presents a novel approach, specifically caching popular videos in smartphone (Friend Node) and disseminating by D2D communication. By placing popular data close to users, this approach facilitates users to download data from FN in proximity enabling significant delay reduction. The proposed work advocates fusion of FN cache in operator controlled long-term evolution-advanced system to improve network performance in terms of delay and jitter. Our simulation result shows that FN caching reduces delay up to 75% while MIX caching reduces delay ranging from 15% to 57%. We also analyze downloading time of various video files under D2D, eNB, EPC, and MIX caching.