Miracle-dz/UniFAR-FTUs huggingface dataset:
Hand layup: understanding the manual process

The hand layup of pre-impregnated woven materials is still a large part of the composite manufacturing industry, requiring the skills and experience of a human workforce to form flat plies into complex shapes. It is capable of producing high performance and complex parts, but can be an expensive and variable process. Despite its importance, there appears to have been very little research into the actual methods and techniques used by workers to manipulate flat sheets of composite material into shape during layup. This work presents the first known detailed study of the approach and techniques used by laminators. Four participants laid up onto 15 different shaped molds that replicated features commonly found on composite components. The actions used in layup were grouped into eight distinct techniques. Use of these techniques across tasks of different geometry, ramp angles, radii and drape path was identified using video analysis techniques from the ergonomics field. This revealed strong links between specific features and techniques, revealing a systematic approach to layup. This has enabled the first step toward producing a design for manufacture knowledge base surrounding hand layup. This could then be used to inform the development of the layup process, improve training methods and assist in the design of future automated solutions. Graphical Abstract
Soil Nitrous Oxide Emissions in Corn following Three Decades of Tillage and Rotation Treatments

Few experiments have directly compared the long-term effects of moldboard, chisel, and no-till tillage practices on N 2 O emissions from the predominant crop rotation systems in the midwestern United States. This study was conducted from 2004 to 2006 on a tillage and rotation experiment initiated in 1975 on a Chalmers silty clay loam (a Typic Endoaquoll) in west-central Indiana. Our objectives were to assess (i) long-term tillage (chisel [CP], moldboard plow [MP], and no-till [NT]), rotation (continuous corn [Zea mays L.] and corn-soybean [Grycine max (L.) Merr. ]), and rotation × tillage interaction effects on soil N 2 O emission, and (ii) how soil N 2 O emission is related to environmental factors during corn production under identical N fertilizer management. Seasonal N 2 O emissions were measured at intervals ranging from a few days to biweekly for up to 14 sampling dates in each growing season for corn. Nitrous oxide emissions during the growing season were significantly affected by tillage and rotation but not their interaction; however, 50% of total emissions occurred shortly after N application regardless of tillage or rotation practices. Seasonal cumulative emissions were significantly lower under NT but not statistically different for CP and MP. Overall, emissions under NT were about 40% lower relative to MP and 57% lower relative to CP. Rotation corn lowered N 2 O emissions by 20% relative to continuous corn. Higher N 2 O emission under MP and CP appeared to be driven by soil organic C decomposition associated with higher levels of soil-residue mixing and higher soil temperatures.
Genetic control over survival in Pacific salmon (Oncorhynchus spp.): experimental evidence between and within populations of New Zealand chinook salmon (O. tshawytscha)

The ability to survive to adulthood and return to natal sites is a fundamental characteristic of anadromous salmonids, and low survival is likely to have prevented establishment of new populations within and outside their native range. We hypothesised that there is family-level genetic variation in traits contributing to survival and that populations evolve to maximise survival in response to prevailing local conditions. To test these predictions, we compared postrelease survival for chinook salmon families from two populations established in New Zealand in the 1900s. Both populations, Glenariffe Stream and Hakataramea River, had similar survival when released after translocation to a drainage familiar to neither population. However, Glenariffe families had higher survival than Hakataramea families when both populations were released from Glenariffe Stream, indicating a survival advantage for the local fish. In addition, there were significant correlations between survival rates for paternal half-sib fami.
Effects of laboratory equipment on secondary school students ’ performance and attitude change to biology learning in federal capital territory , Abuja , Nigeria

The study examined the effects of laboratory equipment on performance and attitude change to biology learning among Senior Secondary School Students in Federal Capital Territory (FCT) Abuja. The study adopted a quasi-experimental pre-test and posttest matched group design. The sample consisted of 136 Senior Secondary School class II (SSSII) biology students. They were drawn from two (2) coeducational Secondary Schools using criterion sampling techniques. Four null hypotheses were tested at 0.05 alpha levels. Three instruments were used. They include: Biology Laboratory Equipment Check List (BLCL), Biology Practical’s Achievement Test (BIOPAT) and Biology Students’ Attitude Change Questionnaire (BSACQ). The reliability indices of BIOPAT and BSACQ were determined using split-half methods and 0.78 and 0.82 indices respectively were established and considered adequate for the study. The reliability index of BLCL was determined using split-half method and a reliability index of 0. 75 were established, which was considered adequate for the study. The findings indicated a significant difference between the performance of biology students exposed to adequately equipped laboratory and those exposed to inadequately equipped laboratory. The difference was in favour of those exposed to adequately equipped laboratory. Also, that, the attitude change of biology students exposed to adequately equipped laboratory is not gender-related. It is therefore recommended that school authorities and stakeholders should ensure that Science laboratories are adequately equipped in Senior Secondary Schools so that they could remain centres of excellence where future scientists, engineers etc are prepared for University education in order to meet the goals of MDGS, EFA and vision 20-2020.
Short Addition Sequences for Theta Functions

The main step in numerical evaluation of classical Sl2 (Z) modular forms and elliptic functions is to compute the sum of the first N nonzero terms in the sparse q-series belonging to the Dedekind eta function or the Jacobi theta constants. We construct short addition sequences to perform this task using N + o(N) multiplications. Our constructions rely on the representability of specific quadratic progressions of integers as sums of smaller numbers of the same kind. For example, we show that every generalised pentagonal number c 5 can be written as c = 2a + b where a, b are smaller generalised pentagonal numbers. We also give a baby-step giant-step algorithm that uses O(N/ log r N) multiplications for any r > 0, beating the lower bound of N multiplications required when computing the terms explicitly. These results lead to speed-ups in practice.
Carbon Nanotubes Influence the Enzyme Activity of Biogeochemical Cycles of Carbon, Nitrogen, Phosphorus and the Pathogenesis of Plants in Annual Agroecosystems

We conducted pre-sowing seed treatment of spring wheat carbon nanotubes modified with thionyl chloride, ethylene diamine, azobenzole, and dodecylamine. CNTs did not disrupt the structure of the crop, but the activity of extracellular enzymes in the rhizosphere of plants in the flowering stage changed: laccase works more poorly in the variant of the CNTs with the amino groups exochitinase and phosphatase activity increased in the case of chlorinated CNTs, OH and COOH groups on the surface of the nanotubes twice accelerate work β-glucosidase. The changes observed in the biogeochemical cycles in the rhizosphere are a possible cause of the effect of nanotubes on the development of epidemic diseases of wheat.
MORPHO-ANATOMICAL DIFFERENTIATION OF THE BALKAN ENDEMIC SPECIES TEUCRIUM ARDUINI L. (LAMIACEAE)

Teucrium arduini L. is an endemic of the Mediteranean to sub-Mediterranean part of the Western Balkans. The ecological plasticity, i.e., inter-population differentiation, of the species Teucrium arduini was analyzed on the basis of morpho-anatomical variability of six populations from different types of vegetation, i.e., of rocky crevices, rocky ground, and a thermophilous forest in the eu-Mediterranean, sub-Mediterranean, and transitional sub-Mediterranean-Central- European climate zones. Univariant statistic analysis included 22 quantitative characters related to leaf and stem anatomy and morphology. In order to establish the variability and significance of morpho-anatomical differentiation, principal component analyses (PCA), multivariant analyses of variances (MANOVA), and discriminant components analysis (DCA) were done. The analyses of plants from these spatially separated populations confirmed that the species T. arduini belongs to the category of xerophytes with malacophyllous leaves.
Assimilation of Sentinel-2 Data into a Snowpack Model in the High Atlas of Morocco

The snow melt from the High Atlas is a critical water resource in Morocco. In spite of its importance, monitoring the spatio-temporal evolution of key snow cover properties like the snow water equivalent remains challenging due to the lack of in situ measurements at high elevation. Since 2015, the Sentinel-2 mission provides high spatial resolution images with a 5 day revisit time, which offers new opportunities to characterize snow cover distribution in mountain regions. Here we present a new data assimilation scheme to estimate the state of the snowpack without in situ data. The model was forced using MERRA-2 data and a particle filter was developed to dynamically reduce the biases in temperature and precipitation using Sentinel-2 observations of the snow cover area. The assimilation scheme was implemented using SnowModel, a distributed energy-balance snowpack model and tested in a pilot catchment in the High Atlas. The study period covers 2015-2016 snow season which corresponds to the first operational year of Sentinel-2A, therefore the full revisit capacity was not yet achieved. Yet, we show that the data assimilation led to a better agreement with independent observations of the snow height at an automatic weather station and the snow cover extent from MODIS. The performance of the data assimilation scheme should benefit from the continuous improvements of MERRA-2 reanalysis and the full revisit capacity of Sentinel-2.
Invasion Potential of Chinese Tallowtree (Triadica sebifera) in California's Central Valley

Abstract The ecological effects of Chinese tallowtree are well documented in the southeastern United States, yet this known invasive plant continues to be planted extensively in California's Central Valley, where it has recently naturalized in several locations. Climate modeling suggests that most of California's lowland riparian habitat is susceptible to invasion by Chinese tallowtree; however, no field tests are available to corroborate this result for California or to identify local environmental constraints that might limit potential habitats. We used observational and experimental methods to evaluate invasion potential of Chinese tallowtree in riparian habitats in California's Central Valley. High invasion potential, indicated by an intersection of the maxima of dispersal probability, germination, and survivorship of seedlings, occurred at low elevations immediately next to perennial waters. The main factor limiting Chinese tallowtree invasion potential in more elevated habitats appears to be lack of seedling drought tolerance. These findings suggest that California's riparian habitats are vulnerable to invasion by Chinese tallowtree, especially downstream of current naturalized populations where water or bird dispersal will deposit seeds in environments ideal for germination and growth. Nomenclature: Chinese tallowtree, Triadica sebifera (L.) Small.
Intergenerational Mobility of Income and Schooling: Chile 1996-2006

In this paper we analyze intergenerational income and schooling mobility during the 1996-2006 decade in Chile. Using the countries most extended household panel survey, we overcome some of the limitations of the previous Chilean studies by using observed income data for both parents and children, as opposed to observed income data only for children and income data that is generated for parents from the information given by their children retrospectively. Following the recent literature, we control our estimates for time-series variation (Lee and Solon, 2009). Our results show high intergenerational income elasticities in comparison to other developing countries, and these values are higher for sons than for daughters. The same results hold for educational mobility. Trends analysis show that the transmission of economic status have remained constant during the last years in Chile, while educational mobility has increased.
Phonological Awareness and Listening Comprehension among Chinese English-Immersion Students.

This study investigates the relationship between English listening comprehension and English and Chinese phonological awareness (PA), and the crosslinguistic transfer of PA in 48 Grade 2 and 47 Grade 4 Chinese English-immersion students. The results of the study indicate a correlation between English PA and English listening comprehension. English listening comprehension had a signifi cant effect on English PA in both grades; this effect is evident after considering Chinese PA, but only in Grade 4. A similar pattern is found for the effect of English PA on English listening comprehension. Only weak evidence exists pertaining to a connection between cross-linguistic transfer from Chinese PA (L1) to English listening comprehension (L2).
Factors Associated with Risky Sexual Behavior among Unmarried Most-at-Risk Young People in Cambodia

Background: Recent surveys suggest that adolescents and young adults in Southeast Asian nations are at great risks of sexual reproductive health issues. This study explored factors associated with risky sexual behavior (RSB) among unmarried most-at-risk young people in Cambodia. Methods: A two-stage cluster sampling method was used to select 1,204 boys and 1,166 girls aged 10-24 from 252 hotspots in the capital city and seven provinces. A five-item scale was constructed to measure RSB. All variables were entered simultaneously in multivariate logistic regression models if they were significantly associated with RSB in bivariate analyses. Results: Of total, 37.7% of boys and 18.5% of girls had sexual intercourse in the past three months; of them, 69.6% of boys and 52.5% of girls were involved in commercial sex. Only 43.3% of boys and 6.5% of girls reported always using condom with unpaid regular partners in the past three months. Among sexually active girls, 43.5% reported having been pregnant and of them, 42.4% reported having induced abortion as a result of their most recent pregnancy. After adjustment, boys with higher levels of RSB were significantly more likely to live in an urban area, to have completed ≥ 9 years of formal education, and to be not currently living with parents. In contrast, girls with higher levels of RSB were significantly less likely to have completed ≥ 9 years of formal education and to have both parents alive. Both boys and girls with higher levels of RSB were significantly more likely to be in the age group of 20-24, to be not currently in school, to be employed, to becurrent alcohol drinkers, to becurrent heavy alcohol drinkers, to be current illicit drug users, and to have been tested for HIV. Conclusions: Unmarried young people in this study are exposed to several sexual reproductive health problems such as HIV and sexually transmitted infections, unwanted pregnancy, and unsafe abortion. These findings suggest the need for research and prevention programs for these key populations taking into account risk factors identified in this study.
The Impact of Dynamic Assessment on Achievement of Students in Physics

Dynamic assessment (DA) originated from Vygotsky’s ZPD theory has been widely accepted and employed as an effective tool to improve students’ learning in recent years. This study investigates the impact of DA on the development of students in physics taught in higher education, that is, at the university level. For the purpose of the present study, sixty undergraduate students in the Faculty of Computing, Engineering and the Built Environment at Ulster University were randomly divided into two groups as experimental group and control group. Over an 8-week period, the students in the experimental group were asked to perform 16 physics tasks through DA procedure, whereas the students in the control group received traditional teaching instruction. Results indicated that the students in experimental group improved their physics knowledge significantly compared to their peers in the control group. The findings of this study suggest that DA is an effective method to improve students' physics knowledge. Keywords : assessment, dynamic assessment, physics education
Theory of differential equations in discontinuous piecewise‐defined functions

A truly general and systematic theory of finite element methods (FEM) should be formulated using, as trial and test functions, piecewise‐defined functions that can be fully discontinuous across the internal boundary, which separates the elements from each other. Some of the most relevant work addressing such formulations is contained in the literature on discontinuous Galerkin (dG) methods and on Trefftz methods. However, the formulations of partial differential equations in discontinuous functions used in both of those fields are indirect approaches, which are based on the use of Lagrange multipliers and mixed methods, in the case of dG methods, and the frame, in the case of Trefftz method. This article addresses this problem from a different point of view and proposes a theory, formulated in discontinuous piecewise‐defined functions, which is direct and systematic, and furthermore it avoids the use of Lagrange multipliers or a frame, while mixed methods are incorporated as particular cases of more general results implied by the theory. When boundary value problems are formulated in discontinuous functions, well‐posed problems are boundary value problems with prescribed jumps (BVPJ), in which the boundary conditions are complemented by suitable jump conditions to be satisfied across the internal boundary of the domain‐partition. One result that is presented in this article shows that for elliptic equations of order 2m, with m ≥ 1, the problem of establishing conditions for existence of solution for the BVPJ reduces to that of the “standard boundary value problem,” without jumps, which has been extensively studied. Actually, this result is an illustration of a more general one that shows that the same happens for any differential equation, or system of such equations that is linear, independently of its type and with possibly discontinuous coefficients. This generality is achieved by means of an algebraic framework previously developed by the author and his collaborators. A fundamental ingredient of this algebraic formulation is a kind of Green's formulas that simplify many problems (some times referred to as Green‐Herrera formulas). An important practical implication of our approach is worth mentioning: “avoiding the introduction of the Lagrange multipliers, or the ‘frame’ in the case of Trefftz‐methods, significantly reduces the number of degrees of freedom to be dealt with. ” © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
THE INFLUENCE OF DISTRIBUTOR SUPPORT AND PRICE ADAPTATION ON THE EXPORT PERFORMANCE OF SMEs

Although a number of studies have examined the antecedents of export performance, little empirical attention has been given to the influence of distribution support and price adaptation on export performance in comparison with other determinants. To address this gap in literature, this study develops a new model, which integrates these two constructs as key variables affecting export performance. A sample of senior managers of export firms in Italy is used to test the hypotheses. The results suggest that support given to the distributor has a strong and positive impact on the firms’ export performance. In addition, the findings indicate that distribution support plays a mediating role in our model. Contrary to expectations, the results show that price adaptation has no significant impact on export performance. Although in the literature price adaptation and export performance is assumed to have a linear relationship, further analysis shows a non-linear (U-shaped) relationship between price adaptation and export performance. The implications of these findings along with the limitations of the study are discussed.
A STUDY OF THE NOISE-LEVEL IN TWO INFRARED MARKER-BASED MOTION CAPTURE SYSTEMS

With musical applications in mind, this paper reports on the level of noise observed in two commercial infrared marker-based motion capture systems: one high-end (Qualisys) and one affordable (OptiTrack). We have tested how various features (calibration volume, marker size, sampling frequency, etc.) influence the noise level of markers lying still, and fixed to subjects standing still. The conclusion is that the motion observed in humans standing still is usually considerably higher than the noise level of the systems. Dependent on the system and its calibration, however, the signal-to-noise-ratio may in some cases be problematic.
Modeling analysis of primary controls on net ecosystem productivity of seven boreal and temperate coniferous forests across a continental transect

Process‐based models are effective tools to synthesize and/or extrapolate measured carbon (C) exchanges from individual sites to large scales. In this study, we used a C‐ and nitrogen (N)‐cycle coupled ecosystem model named CN‐CLASS (Carbon Nitrogen‐Canadian Land Surface Scheme) to study the role of primary climatic controls and site‐specific C stocks on the net ecosystem productivity (NEP) of seven intermediate‐aged to mature coniferous forest sites across an east–west continental transect in Canada. The model was parameterized using a common set of parameters, except for two used in empirical canopy conductance–assimilation, and leaf area–sapwood relationships, and then validated using observed eddy covariance flux data. Leaf Rubisco‐N dynamics that are associated with soil–plant N cycling, and depend on canopy temperature, enabled the model to simulate site‐specific gross ecosystem productivity (GEP) reasonably well for all seven sites. Overall GEP simulations had relatively smaller differences compared with observations vs. ecosystem respiration (RE), which was the sum of many plant and soil components with larger variability and/or uncertainty associated with them. Both observed and simulated data showed that, on an annual basis, boreal forest sites were either carbon‐neutral or a weak C sink, ranging from 30 to 180 g C m−2 yr−1; while temperate forests were either a medium or strong C sink, ranging from 150 to 500 g C m−2 yr−1, depending on forest age and climatic regime. Model sensitivity tests illustrated that air temperature, among climate variables, and aboveground biomass, among major C stocks, were dominant factors impacting annual NEP. Vegetation biomass effects on annual GEP, RE and NEP showed similar patterns of variability at four boreal and three temperate forests. Air temperature showed different impacts on GEP and RE, and the response varied considerably from site to site. Higher solar radiation enhanced GEP, while precipitation differences had a minor effect. Magnitude of forest litter content and soil organic matter (SOM) affected RE. SOM also affected GEP, but only at low levels of SOM, because of low N mineralization that limited soil nutrient (N) availability. The results of this study will help to evaluate the impact of future climatic changes and/or forest C stock variations on C uptake and loss in forest ecosystems growing in diverse environments.