pinecone/core-2020-05-10-deduplication huggingface dataset:
Influence of Strouhal number on pulsating methane–air coflow jet diffusion flames

Four periodically time-varying methane–air laminar coflow jet diffusion flames, each forced by pulsating the fuel jet's exit velocity Uj sinusoidally with a different modulation frequency wj  and with a 50% amplitude variation, have been computed. Combustion of methane has been modeled by using a chemical mechanism with 15 species and 42 reactions, and the solution of the unsteady Navier–Stokes equations has been obtained numerically by using a modified vorticity-velocity formulation in the limit of low Mach number. The effect of wj on temperature and chemistry has been studied in detail. Three different regimes are found depending on the flame's Strouhal number S=awj/Uj, with a denoting the fuel jet radius. For small Strouhal number (S=0.1), the modulation introduces a perturbation that travels very far downstream, and certain variables oscillate at the frequency imposed by the fuel jet modulation. As the Strouhal number grows, the nondimensional frequency approaches the natural frequency of oscillation of the flickering flame (S≃0.2). A coupling with the pulsation frequency enhances the effect of the imposed modulation and a vigorous pinch-off is observed for S=0.25 and S=0.5. Larger values of S confine the oscillation to the jet's near-exit region, and the effects of the pulsation are reduced to small wiggles in the temperature and concentration values. Temperature and species mass fractions change appreciably near the jet centerline, where variations of over 2% for the temperature and 15% and 40% for the CO and OH mass fractions, respectively, are found. Transverse to the jet movement, however, the variations almost disappear at radial distances on the order of the fuel jet radius, indicating a fast damping of the oscillation in the spanwise direction
Integral energy performance characterization of semi-transparent photovoltaic elements for building integration under real operation conditions

In this paper, a methodology for the integral energy performance characterization (thermal, daylighting and electrical behavior) of semi-transparent photovoltaic modules (STPV) under real operation conditions is presented. An outdoor testing facility to analyze simultaneously thermal, luminous and electrical performance of the devices has been designed, constructed and validated. The system, composed of three independent measurement subsystems, has been operated in Madrid with four prototypes of a-Si STPV modules, each one corresponding to a specific degree of transparency. The extensive experimental campaign, continued for a whole year rotating the modules under test, has validated the reliability of the testing facility under varying environmental conditions.\ud
\ud
The thermal analyses show that both the solar protection and insulating properties of the laminated prototypes are lower than those achieved by a reference glazing whose characteristics are in accordance with the Spanish Technical Building Code. Daylighting analysis shows that STPV elements have an important lighting energy saving potential that could be exploited through their integration with strategies focused to reduce illuminance values in sunny conditions. Finally, the electrical tests show that the degree of transparency is not the most determining factor that affects the conversion efficiency
Helios 3198 solar simulator adaptation for the characterization of LCPV prototypes

This paper covers the adaptation and experimental verification that has been carried out to the Helios 3198 solar simulator to use it in the characterization of a LCPV prototype. The challenge is to deal with the diffuse light that can distort the measurement of a LCPV prototype because of the larger acceptance angle. A deflector chamber for the flash lamp has been designed and implemented to capture this diffuse light. The experimental verification has proven the reliability of the solution, demonstrating that the inclusion of this element in the equipment is not modifying the spatial uniformity and the angular distribution of the light at the receiver plane. Therefore, this work demonstrates that the Helios 3198 solar simulator, including a deflector chamber for the lamp, can be used for the characterization of a LCPV prototype
A methodology to measure sight-hidden dips'parameters.

Highway design standards specify several requirements on available sight distance. Usually, compliance with these standards is ensured during the design phase of a new road.\ud
This is made through geometric calculations that take into account the terrain and the road. In this paper, a procedure for measuring distances in an existing road from georeferenced photographs is proposed. In addition, an estimation of the error committed when using this procedure is made. Distances measured using this procedure arecompared with the ones measured using a Global Navigation Satellite System (GNSS). Distances error is\ud
within the error estimation and is low enough for using it in traffic safety studies. In addition, the procedure is applied to measure several parameters of a sight-hidden dip. This procedure does not need a terrain model to measure these parameters. This is an advantage compared with other existing procedures for estimating the parameters of sight-hidden dips
Molecular Structure and Bonding in Plutonium Carbides: A Theoretical Study of PuC3

Producción CientíficaThe most relevant species of plutonium tricarbide were characterized using theoretical methods. The global minimum is predicted to be a fan structure where the plutonium atom is bonded to a quasi-linear C3 unit. A rhombic isomer, shown to be a bicyclic species with transannular C-C bonding, lies about 39 kJ/mol above the fan isomer. A linear PuCCC isomer and a three-membered ring CPuC2 isomer were found to be higher in energy (150 and 195 kJ/mol, respectively, above the predicted global minimum). The possible processes for the formation of these species are discussed, and the IR spectra were predicted to help in possible experimental detection. The nature of the Pu-C interaction has been analyzed in terms of a topological analysis of the electronic density, showing that Pu-C bonding is essentially ionic with a certain degree of covalent character.Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA330U13
Modelling math learning on an open access intelligent tutor

This paper presents a methodology to analyze large amount of students’ learning states on two math courses offered by Global Fresh- man Academy program at Arizona State University. These two courses utilised ALEKS (Assessment and Learning in Knowledge Spaces) Arti- ficial Intelligence technology to facilitate massive open online learning. We explore social network analysis and unsupervised learning approaches (such as probabilistic graphical models) on these type of Intelligent Tu- toring Systems to examine the potential of the embedding representa- tions on students learning
Potential of utilizing asphalt dust waste as filler material in the production of
sustainable self compacting concrete (SCC)

Waste materials from many industries are widely used in the production of sustainable green concrete. Utilizing
asphalt dust waste (ADW) as a filler material in the development of self-compacting concrete (SCC) is one of the alternative
solutions for reducing environmental waste. SCC is an innovative concrete that does not require vibration for placing and
compaction. However, there is limited information on the effects of utilizing ADW in the development of SCC. Therefore,
this research study examines the effects of various w/b ratios (0.2, 0.3 and 0.4) and differing amounts of ADW (0% to
50%) on the rheological properties of fresh state concrete. The compressive strength of the SCC was tested only for 7 and
28 days as preliminary studies. The results revealed that mixtures MD730, MD740 and MD750 showed satisfactory results
for the slump flow, J-Ring, L-Box and V-Funnel test during the fresh state. The compressive strength values obtained after
28 days for MD730, MD740 and MD750 were 35.1 MPa, 36.8 MPa and 29.4 MPa respectively. In conclusion, the distribution
of materials in mixtures has significant effect in achieving rheological properties and compressive strength of SCC
Mixed alumina and cobalt containing plasma electrolytic oxide coatings

Principles of plasma electrolytic oxidation of the AL25 aluminum alloy in diphosphate alkali solutions containing cobalt(2+) cations are discussed. It has been established that a variation in the concentration of the electrolyte components provides the formation of mixed-oxide coatings consisting of the basic matrix materials and the cobalt oxides of different content. An increase in the cobalt oxide content in the coating is achieved by the variation in electrolysis current density as well as the treatment time due to both the electrochemical and thermo-chemical reactions at substrate surface and in spark region. Current density intervals that provide micro-globular surface formation and uniform cobalt distribution in the coating are determined. The composition and morphology of the surface causes high catalytic properties of synthesized materials, which confirmed the results of testing in model reaction CO and benzene oxidation as well as fuel combustion for various modes of engine operation
Cycloaddition of trifluoromethyl azafulvenium methides: synthesis of new trifluoromethylpyrrole-annulated derivatives

The chemistry of trifluoromethyl azafulvenium methides was explored leading to a new route to trifluoromethylpyrrole-annulated systems. The first evidence of azafulvenium methides acting as 1,3-dipoles is reported. These azafulvenium methides showed site selectivity in the reaction with strong electron-deficient dipolarophiles leading exclusively to 1,3-cycloadducts. In the cycloaddition with less-activated dipolarophiles 1,7-cycloadducts resulting from [8π+2π] cycloaddition are also formed. FMO analysis of the cycloaddition reactions allowed the rationalization of the observed selectivity.

Graphical abstrac
Aphasic seizures in patients with temporopolar and anterior temporobasal lesions: a video-EEG study

Studies of patients with temporal lobe epilepsy provide few descriptions of seizures that arise in the temporopolar and the anterior temporobasal brain region. Based on connectivity, it might be assumed that the semiology of these seizures is similar to that of medial temporal lobe epilepsy. However, accumulating evidence suggests that the anterior temporobasal cortex may play an important role in the language system, which could account for particular features of seizures arising here. We studied the electroclinical features of seizures in patients with circumscribed temporopolar and temporobasal lesions in order to identify specific features that might differentiate them from seizures that originate in other temporal areas. Among 172 patients with temporal lobe seizures registered in our epilepsy unit in the last 15 years, 15 (8.7%) patients had seizures caused by temporopolar or anterior temporobasal lesions (11 left-sided lesions). The main finding in our study is that patients with left-sided lesions had aphasia during their seizures as the most prominent feature. In addition, while all patients showed normal to high intellectual functioning in standard neuropsychological testing, semantic impairment was found in a subset of 9 patients with left-sided lesions. This case series demonstrates that aphasic seizures without impairment of consciousness can result from small, circumscribed left anterior temporobasal and temporopolar lesions. Thus, the presence of speech manifestation during seizures should prompt detailed assessment of the structural integrity of the basal surface of the temporal lobe in addition to the evaluation of primary language areas
Constraints on ultraviolet-stable fixed points in supersymmetric gauge
  theories

We consider the possibility that some supersymmetric gauge theories which are
not asymptotically free can be governed by ultraviolet-stable fixed points. If
this scenario can be realized, gaugino masses will exhibit power-law running
with scale, providing a possible solution to the supersymmetric flavor problem.
While naive perturbative calculations hint at the appearance of
ultraviolet-stable fixed points in certain theories, there are strong
constraints following from limits on the scaling dimensions of gauge-invariant
operators, positivity of central charges, and Cardy's conjectured constraint on
the flow of the Euler coefficient in the stress tensor trace anomaly. Also, we
prove that if ultraviolet-stable fixed points do exist, they cannot occur in
the perturbative regime of a renormalizable model, and that all-orders results
in the limit of large numbers of chiral superfields are necessarily
inconclusive. However, we argue that the general idea of ultraviolet-stable
fixed points in supersymmetric gauge theories is viable, and exhibit models
that can satisfy all known constraints.Comment: 12 page
A Kinematic Approach for 6-DOF Part Positioning

Lien vers la version éditeur: http://link.springer.com/chapter/10.1007%2F978-3-642-30817-8_15This article proposes a fixturing system consists of a cuboid basep-late located through a 3-2-1 configuration of locators. The locators are mounted on machine table/pallet and posses one axial DOF. The workpiece is mounted on the baseplate and all the elements are assumed to be rigid with zero friction. 
The  positioning  error  of  the  workpiece  is  calculated  and  the  compensation  is 
performed by the axial movement of the locators. The proposed analytical mod-
el is verified by the simulation performed in the CAD model
Validation and intercomparison of ocean wave spectra inversion schemes using ASAR wave mode data

This paper presents a validation and intercomparison of the non-linear Partition Rescaling and Shift Algorithm (PARSA) for deriving full two-dimensional ocean wave spectra from ENIVSAT Advanced Synthetic Aperture Radar (ASAR) Wave\ud
Mode (WM) data. \ud
ASAR WM data acquired globally are used for the validation exercise by comparing the retrieved significant wave height (SWH), zero up-crossing wave period (Tm02), swell SWH (H12, for waves with a period longer than 12 s), mean wave\ud
frequency and mean wave direction to in situ buoy measurements and results from the European Centre for Medium-Range Weather Forecast (ECMWF) reanalysis\ud
wave model and the Deutscher Wetterdienst (DWD) forecast wave model.\ud
An intercomparison of results from the PARSA algorithm with those from the quasi-linear retrieval algorithm adopted by the European Space Agency (ESA) to generate the ASAR WM level-2 product (ASA_WVW_2P, termed WVW hereafter)\ud
is also presented in this paper. In addition to the intercomparison with the existing ASAR WM WVW product, sea state parameters (SWH and Tm02), integrated from the PARSA spectra are also compared to the results derived using the empirical algorithm CWAVE_ENV. \ud
Validation results indicate that the PARSA inversion can yield full two-dimensional ocean wave spectra. The retrieved SWH corresponds well to buoy measurements with a scatter index of 21%, as demonstrated by 1247 collocated data pairs. By comparing SWH to the ECMWF reanalysis wave model and the\ud
DWD forecast wave model, better agreement is achieved, with scatter indices of 9% and 16%, respectively.\ud
In addition to comparing conventional integral wave parameters normally used to assess the quality of inverted spectra, a comparison of individual PARSA spectra chosen in different sea state with the nearest numerical wave model spectra and the WVW spectra is performed to illustrate two-dimensional spectral differences.\u
Novel techniques for automorphism group computation

Graph automorphism (GA) is a classical problem, in which the objective is to compute the automorphism group of an input graph.\ud
In this work we propose four novel techniques to speed up algorithms that solve the GA problem by exploring a search tree. They increase the performance of the algorithm by allowing to reduce the depth of the search tree, and by effectively pruning it.\ud
We formally prove that a GA algorithm that uses these techniques correctly computes the automorphism group of the input graph. We also describe how the techniques have been incorporated into the GA algorithm conauto, as conauto-2.03, with at most an additive polynomial increase in its asymptotic time complexity.\ud
We have experimentally evaluated the impact of each of the above techniques with several graph families. We have observed that each of the techniques by itself significantly reduces the number of processed nodes of the search tree in some subset of graphs, which justifies the use of each of them. Then, when they are applied together, their effect is combined, leading to reductions in the number of processed nodes in most graphs. This is also reflected in a reduction of the running time, which is substantial in some graph families
Classical solutions for a logarithmic fractional diffusion equation

We prove global existence and uniqueness of strong solutions to the logarithmic porous medium type equation with fractional diffusion ?tu + (?)1/2 log(1 + u) = 0, posed for x ? R, with nonnegative initial data in some function space of LlogL type. The solutions are shown to become bounded and C? smooth in (x, t) for all positive times. We also reformulate this equation as a transport equation with nonlocal velocity and critical viscosity, a topic of current relevance. Interesting functional inequalities are involved
Mobilization and Impacts of Bio-Gas Technologies

At present, energy and fertilizer requirements of many of the developing countries are largely met by locally available, non-commercial sources, such as firewood and farm wastes. Extensive use of firewood is one of the factors that can lead to deforestation. When organic farm wastes are burnt, soil nutrients, which should return to soil, are lost and this can severely affect agricultural production. The problem of efficient utilization of these locally available resources,  therefore, needs to be studied in a systematic manner. As an option for efficient utilization of local resources, bio-gas  plants are considered, taking India as a case study. In these plants, animal dung and agricultural byproducts are utilized to obtain both methane and fertilizer through anaerobic fermentation. This is an example of appropriate technology for rural environments, which requires low investment, which does not need highly skilled labor  and which can be operated with local materials and self-help in the 576,000 villages of India. The economic benefits to a family using a bio-gas plant and the impact of its widespread acceptance on a national scale are evaluated. It is felt, however, that the scope of such individual family bio-gas plants is likely to be limited for a number of reasons. To realize the potential of bio-gas fully, village plants of about 200 cubic meter capacity for approximately 100 families are needed. (Reprint from Energy, Vol. 2, pp. 441-455. Pergamon Press 1977.
Technology Dynamics and Greenhouse Gas Emissions Mitigation: A Cost Assessment

This article analyzes long-term greenhouse gas (GHG) emissions and their mitigation in a family of high economic and energy demand growth scenarios in which technological change unfolds in alternative "path dependent" directions. Four variants of this family are developed and used as baseline scenarios, for which alternative policy cases leading to a stabilization of atmospheric CO2 concentrations at 450, 550, 650, and 750 ppmv by the end of the 21st century are examined. The baseline scenarios share common demographic, economic, and energy demand developments, but explore alternative development pathways of technological change and resource availability. We illustrate the sensitivity of projected future GHG emission levels and resulting global climate change to alternative developments in energy systems technologies. We conclude that uncertainties in technological change are as important for determining future GHG emissions as uncertainties in long-term demographic and economic developments. We also illustrate that differences in costs between alternative baseline scenarios of technological change may be larger than the cost differences of reaching alternative environmental (climate change stabilization) targets. Under our assumptions of high economic and energy demand growth, even in scenarios favoring fossil fuels, the long-term energy portfolio needs to include improvements in zero-carbon technologies and carbon-related technologies and infrastructures. We suggest that improvements in these technology options are a robust hedging strategy for an uncertain energy future
Top quark forward-backward asymmetry in the little Higgs model

A sizable difference in top quark pair forward backward asymmetry (AFB) is observed at Tevatron. The discrepancy triggers many new physics beyond the standard model (SM) and then constrains the parameter spaces in them. In this article we calculate the AFB of the top-pair production at Tevatron up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of ZH can be large enough to make up the gap between SM prediction and experimental data. Then, the parameter space for the couplings between ZH and quarks are constrained. Thus, this model can fulfill the experimental data, both in AFB and in cross section
Rising Power Clusters and the Challenges of Local and Global Standards

__Abstract__\ud
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This paper explores the intersection between three processes associated with globalisation. First, the rise of emerging economies like China, Brazil and India, the so-called ‘Rising Powers’, and their potential to define the contours of globalisation, global production arrangements and global governance in the twenty-first century. Second, the importance of corporate social responsibility (CSR) goals in the shaping of global trade rules and industrial practices. Third, the significance of small firm clusters as critical sites of industrial competitiveness. Some of the most significant examples of successful, innovative and internationally competitive small firm clusters from the developing world are located in the ‘Rising Powers’ and cluster promotion is a core element of national industrial policy in some of these countries. There is also evidence of engagement by clustered actors with corporate social responsibility goals around labour and environmental impacts. While these three processes have been separately studied there has been no attempt to explore their intersections. This paper addresses this gap through a comparative analysis of secondary data, and a detailed reading of the literature, on CSR and clusters in Brazil, China and India. It assesses the evidence on small firm clusters in the Rising Power economies and considers how these Rising Power clusters engage with CSR goals pertaining to labour, social and environmental standards. It argues for a greater focus on the formal and informal institutional context, termed the ‘social contract’, in explaining divergent experiences and practices observed across these countries. This raises important questions for future academic and policy research on clusters, CSR and the Rising Powers. The paper concludes by outlining a research agenda to explore the local and global consequences of the relationship between Rising Power clusters and international labour and environmental standards