Miracle-dz/UniFAR-FTUs huggingface dataset:
An enhanced GWMA chart for process mean

Abstract Memory-type control charts are frequently used to monitor small-to-moderate disturbances in the process parameter(s). Recently, an auxiliary-information-based (AIB) exponentially weighted moving average (EWMA) chart has been proposed for efficiently monitoring the process mean, called the AIB-EWMA chart, that surpasses the classical EWMA chart. On similar lines, in order to further enhance the sensitivity of the AIB-EWMA chart, we propose an AIB generally weighted moving average (GWMA) chart for monitoring the process mean, named the AIB-GWMA chart. The existing AIB-Shewhart and AIB-EWMA charts are special cases of the AIB-GWMA chart. With the help of Monte Carlo simulation, the run length characteristics of the AIB-GWMA chart are computed. It turns out that the AIB-GWMA chart performs uniformly and substantially better than the classical GWMA chart. Moreover, the AIB-GWMA chart also outperforms the AIB-EWMA chart when detecting mean shifts within certain ranges. A similar trend is observed when the proposed and existing control charts are compared with the fast initial response features. An example is used to explain the working and implementation of the GWMA, AIB-EWMA and AIB-GWMA charts.
Effects of Process Parameters on Vibration Frequency in Turning Operations of Perspex Material

Effects of process parameters on vibration frequency of Perspex round plastic bars was investigated experimentally under clamped - free (C - F) boundary condition during turning operation. Mathematical models were developed using Taguchi L9 orthogonal array design. Spindle speed (V), feed rate (f), and depth of cut (d) were selected as input variables in order to predict the effects of vibration frequency on the work-piece. Nine samples were run in a CNC lathe machine, and each of the experimental result was measured using DTO 32105 frequency analyser and a MXC-1600 digital frequency counter. A minimum vibration frequency of 104.8 Hz was obtained at a cutting speed of 320 m/min, feed rate 0.05 min/rev and at a depth of cut of 0.5 mm. The mathematical model developed shows the accuracy of predicting the vibration frequency to be 99.5% and the various combinations of parameters that results in the minimum vibration frequency were determined. Obtained optimum input parameters for vibration frequency indicated that production operations of Perspex round plastic bars could be enhance
Long wavelength infrared quantum cascade detector with a broadband response

A novel structure to achieve long wavelength infrared broadband detection ranging from 7.6–10.4 µm is proposed via quantum cascade detector. With a pair of identical coupled quantum wells separated by a thin barrier, acting as absorption regions, the relative linewidth (ΔE/E) of response can be dramatically broadened to 30.7%. Moreover, this structure introduces about 30% enhancement in blackbody responsivity. It is shown that the spectral shape can be tuned by the bias voltage effectively, while it is insensitive to the working temperature. The device can work at liquid nitrogen temperature with Johnson noise limited blackbody detectivity of 5.4 × 108 Jones.
Weighted recurrence networks for the analysis of time-series data

Recurrence networks (RNs) have become very popular tools for the nonlinear analysis of time-series data. They are unweighted and undirected complex networks constructed with specific criteria from time series. In this work, we propose a method to construct a ‘weighted recurrence network’ from a time series and show that it can reveal useful information regarding the structure of a chaotic attractor which the usual unweighted RN cannot provide. Especially, a network measure, the node strength distribution, from every chaotic attractor follows a power law (with exponential cut off at the tail) with an index characteristic to the fractal structure of the attractor. This provides a new class among complex networks to which networks from all standard chaotic attractors are found to belong. Two other prominent network measures, clustering coefficient and characteristic path length, are generalized and their utility in discriminating chaotic dynamics from noise is highlighted. As an application of the proposed measure, we present an analysis of variable star light curves whose behaviour has been reported to be strange non-chaotic in a recent study. Our numerical results indicate that the weighted recurrence network and the associated measures can become potentially important tools for the analysis of short and noisy time series from the real world.
The effects of third-party transfers in sequential anchored bargaining

We analyze a bargaining game where an anchor player bargains sequentially with n non-anchor players over the division of a pie in the presence of third-party transfers and show that there exists a unique perfect equilibrium. A lump-sum transfer is jointly shared by all players, while a transfer proportional to a player’s share affects only the party that has to make that transfer. When lump-sum transfers are zero, the anchor player and each non-anchor player bargain as if there is no further bargaining. It turns out that the anchor player and the last non-anchor player are in the most disadvantageous position with our bargaining protocol.
Droplet Regulation and Dropwise Condensation Heat Transfer Enhancement on Hydrophobic-Superhydrophobic Hybrid Surfaces

ABSTRACT Efficient Dropwise condensation on nanostructured superhydrophobic surfaces (SHS) has received extensive attention. However, good heat performance only occurs in two conditions: the presence of non-condensable gas, or low surface subcooling. For industrial pure steam condensation, large droplets tend to be pinned on the surfaces due to the large contact angle hysteresis (CAH) and impede heat transfer process. In this study, the SHSs and hydrophobic surface (HS) were integrated in spaced band pattern with different width and CAH. It was observed that the condensed droplets experience a fast horizontal shifting from hydrophobic zones to superhydrophobic zones driven by adhesive force. In this way, the departure path of droplets were altered and the refreshing frequencies are increased for both SHS and HS regions. The heat transfer coefficients for some 1 mm × 1 mm hybrid surfaces were found to be elevated by about 25% at subcooling of 6K compared to the weighted mean value of individual HSs and SHSs. For surfaces with short dividing distance (about 0.5 mm × 0.5 mm), the bridging effects between droplets in SHS regions were also observed, which is undesirable for heat transfer. These work indicates that strong adhesive force of SHSs can function as a promoter of droplet condensation for hybrid surfaces with proper choice of dividing width.
On velocity gradient dynamics and turbulent structure

The statistics of the velocity gradient tensor $\unicode[STIX]{x1D63C}=\boldsymbol{{\rm\nabla}}\boldsymbol{u}$ , which embody the fine scales of turbulence, are influenced by turbulent ‘structure’. Whilst velocity gradient statistics and dynamics have been well characterised, the connection between structure and dynamics has largely focused on rotation-dominated flow and relied upon data from numerical simulation alone. Using numerical and spatially resolved experimental datasets of homogeneous turbulence, the role of structure is examined for all local (incompressible) flow topologies characterisable by $\unicode[STIX]{x1D63C}$ . Structures are studied through the footprints they leave in conditional averages of the $Q=-\text{Tr}(\unicode[STIX]{x1D63C}^{2})/2$ field, pertinent to non-local strain production, obtained using two complementary conditional averaging techniques. The first, stochastic estimation, approximates the $Q$ field conditioned upon $\unicode[STIX]{x1D63C}$ and educes quantitatively similar structure in both datasets, dissimilar to that of random Gaussian velocity fields. Moreover, it strongly resembles a promising model for velocity gradient dynamics recently proposed by Wilczek & Meneveau (J. Fluid Mech., vol. 756, 2014, pp. 191–225), but is derived under a less restrictive premise, with explicitly determined closure coefficients. The second technique examines true conditional averages of the $Q$ field, which is used to validate the stochastic estimation and provide insights towards the model’s refinement. Jointly, these approaches confirm that vortex tubes are the predominant feature of rotation-dominated regions and additionally show that shear layer structures are active in strain-dominated regions. In both cases, kinematic features of these structures explain alignment statistics of the pressure Hessian eigenvectors and why local and non-local strain production act in opposition to each other.
On the asymptotic behaviour of 2D stationary Navier–Stokes solutions with symmetry conditions

We consider the 2D stationary incompressible Navier-Stokes equations in ℝ2. Under suitable symmetry, smallness and decay at infinity conditions on the forcing we determine the behaviour at infinity of the solutions. Moreover, when the forcing is small, satisfies suitable symmetry conditions and decays at infinity like a vector field homogeneous of degree -3, we show that there exists a unique small solution whose asymptotic behaviour at infinity is homogeneous of degree -1.
Experimental investigation on axial velocity distribution for ship’s twin-propeller jets

Abstract The investigation of twin-propeller jets as ships undergo acceleration is essential. This form of jet has been triggering problematic consequences such as seabed scouring. In order to prevent such scouring, near-bed velocities must first be analyzed in order to design the necessary protection when the under keel clearance of a ship is low when it is near port structures. This paper presents experimental work performed by Laser Doppler Anemometry. It is noticed that research into twin-propeller jet profiles still remains limited in the literature. Therefore, we intend to analyze twin-propeller axial velocity profiles and look into several flow characteristics such as efflux velocity and its decay pattern. Also, the measured velocity profile is compared to that of a single-propeller jet. Current results show that scouring is more severe in the case of the twin-propeller jets.
GENERALISATION OF THE INVERSE EXPONENTIAL DISTRIBUTION:STATISTICAL PROPERTIES AND APPLICATIONS

There are several real life data sets that do not follow the Normal distribution; these category of data sets are either negatively or positively skewed. However, some could be slightly skewed while others could be heavily skewed. Meanwhile, most of the existing standard theoretical distributions are deficient in terms of performance when applied to data sets that are heavily skewed. To this end, the aim of this study is to extend the Inverse Exponential distribution by inducing it with skewness with a view to enhancing its efficiency. This was achieved by generalising the Inverse Exponential distribution using four different generalised families of distributions. The resulting generalised distributions are: the Kumaraswamy Inverse Exponential (KIE), Transmuted Inverse Exponential (TIE), Exponentiated Generalised Inverse Exponential (EGIE) and Weibull Inverse Exponential (WIE) distributions. Explicit expressions for the densities and basic statistical properties of these compound distributions were established, the method of maximum likelihood estimation (MLE) was used in estimating the unknown parameters and these distributions were fitted to twelve (12) real life data sets to assess their flexibility. R software was adopted and used to perform all the analyses in this study. In addition, a new generalised family of distributions named the Exponential Generalised family of distributions has been defined and explored. Part of the main results in this study include a statistical table that was generated for the Inverse Exponential distribution. A simulation study was also conducted and it was concluded that the standard error and biasedness generated by the parameters of the Exponential Inverse Exponential distribution became small as the sample size increases. Excerpt from the analysis indicates that the derived generalised distributions are more flexible than their sub-models but for the exception of data sets with large variance and outliers. It is recommended that more link functions that will result in generalised families of distributions with only one additional shape parameter and void of special functions should be developed.
A sparse variable selection procedure in model-based clustering

Au vu de l'augmentation du nombre de jeux de donnees de grande dimension, la selection de variables pour la classification non supervisee est un enjeu important. Dans le cadre de la classification par melanges gaussiens, nous reformulons le probleme de selection de variables en un probleme general de selection de modele. Dans un premier temps, notre procedure consiste a construire une sous-collection de modeles grâce a une methode de regularisation l1. Puis, l'estimateur du maximum de vraisemblance est determine via un algorithme EM pour chaque modele. Enfin un critere penalise non asymptotique est propose pour selectionner a la fois le nombre de composants du melange et l'ensemble des variables informatives pour la classification. D'un point de vue theorique, un theoreme general de selection de modeles dans le cadre de l'estimation par maximum de vraisemblance avec une collection aleatoire de modeles est etabli. Il permet en particulier de justifier la forme de la penalite de notre critere, forme qui depend de la complexite de la collection de modeles. En pratique, ce critere est calibre grâce a la methode dite de l'heuristique de pente. Cette procedure est illustree sur deux jeux de donnees simulees. Finalement, une extension, associee a une modelisation plus generale des variables non informatives pour la classification, est proposee.
Comparison of compressible and incompressible numerical methods in simulation of a cavitating jet through a poppet valve

ABSTRACT The regime of compressible flow generally refers to the super/subsonic case. However, several remarkable cases with low Mach number could not be appropriately described with the incompressible method. It is a similar case for a cavitating jet inside a poppet valve. In order to comprehensively address the discrepancy between incompressible and compressible methods, both non-cavitating and cavitating cases are performed in experiment and calculation based on OpenFOAM. Experiment reveals a transition in flow pattern in both non-cavitating and cavitating flow. For example, for 0.7 mm openness and 30-degree poppet angle, transition happens at approximately 29 and 27 bar pressure drop for the two cases, respectively. In general, results from the compressible method exhibit better agreement with experiment regarding both flow performance and flow structure. By contrast, the incompressible method could not provide an accurate description for the transition process under the applied flow condition. A series of studies are carried out with emphasis on such discrepancy. Firstly, the deviation in flow performance is addressed based on velocity profile and turbulence level. Secondly, the disparity in flow structure is illustrated and the mechanism for cavitation inception is discussed, which combined provide an interpretation of the deficiency of the incompressible method. Thirdly, different inlet boundary conditions are applied, and the results confirm the independence of deficiency of the incompressible method for inlet fluctuation. Finally, a re-examination is proposed concerning traditional notion of compressible flow as well as the applicability of incompressible numerical method.
Application of resonance method for examining of piston ring technical condition

The article is devoted to the questions of technical operation of the internal combustion engines. Some questions of the technical diagnostics of the engine piston rings are considered. The authors propose a resonance method for the examination of the piston rings. The idea of the method is to cause oscillations in the ring at the frequency of its own mechanical resonance and at the multiple harmonics. The amplitude of the ring oscillations is measured in the gap by means of sensors according to two coordinates simultaneously. The frequency, phase and amplitude of the oscillations depend on the mechanical properties of the ring’s material and its geometry. Micro-cracks, the areas with stresses, hardening defects, local overheating, loss of elasticity and other defects cause deviations of the frequency, phase and amplitude from the standard. One of the special features of the proposed method is registration of the frequency response of the piston ring oscillations simultaneously in two planes – radial (the plane of the ring) and in the direction of the axis. It allows to discover the defects (microcracks, thermal inhomogeneity, etc.) of the ring independently on their orientation along the assumed axes. This is a kind of non-destructive methods.
Emissions and possible environmental Implication of engineered nanomaterials (ENMs) in the atmosphere

In spite of the still increasing number of engineered nanomaterial (ENM) applications, large knowledge gaps exist with respect to their environmental fate, especially after release into air. This review aims to summarize the current knowledge of emissions and behavior of airborne engineered nanomaterials. The whole ENM lifecycle is considered from the perspective of possible releases into the atmosphere. Although in general, emissions during use phase and end-of-life seem to play a minor role compared to entry into soil and water, accidental and continuous emissions into air can occur especially during production and some use cases such as spray application. Implications of ENMs on the atmosphere as e.g.; photo-catalytic properties or the production of reactive oxygen species are reviewed as well as the influence of physical processes and chemical reactions on the ENMs. Experimental studies and different modeling approaches regarding atmospheric transformation and removal are summarized. Some information exists especially for ENMs, but many issues can only be addressed by using data from ultrafine particles as a substitute and research on the specific implications of ENMs in the atmosphere is still needed. © 2017 by the authors.
Evaluating the causal economic impacts of transport investments: evidence from the Madrid–Barcelona high speed rail corridor

ABSTRACT This paper evaluates economic impacts arising from the introduction of high-speed rail (HSR) between Madrid and Barcelona. Using difference-in-differences estimation we estimate an average treatment effect for provinces with stops on the HSR line of 2.4% for economic output, 3.3% for numbers of firms, and 1.1% for labour productivity. We complement our DID results with a synthetic control analysis for Lleida and Tarragona, two provinces that we argue were assigned HSR stations largely due to their incidental location. We find that both the number of firms and labour productivity are substantially higher in these provinces than in their synthetic counterparts.
High-resolution data assimilation through stochastic subgrid tensor and parameter estimation from 4DEnVar

Abstract In this paper, we explore a dynamical formulation allowing to assimilate high-resolution data in a large-scale fluid flow model. This large-scale formulation relies on a random modelling of the small-scale velocity component and allows to take into account the scale discrepancy between the dynamics and the observations. It introduces a subgrid stress tensor that naturally emerges from a modified Reynolds transport theorem adapted to this stochastic representation of the flow. This principle is used within a stochastic shallow water model coupled with an 4DEnVar assimilation technique to estimate both the flow initial conditions and the inhomogeneous time-varying subgrid parameters. The performance of this modelling has been assessed numerically with both synthetic and real-world data. Our strategy has shown to be very effective in providing a more relevant prior/posterior ensemble in terms of the dispersion compared to other tests using the standard shallow water equations with no subgrid parameterization or with simple eddy viscosity models. We also compared two localization techniques. The results indicate the localized covariance approach is more suitable to deal with the scale discrepancy-related errors.
D=10 Super Yang Mills, D=11 Supergravity and the Pure Spinor Superfield Formalism

It is well known how to describe the D = 10 (SYM) Super Yang-Mills and D = 11 (SG) Supergravity theories on superspace and by component fields. However, a new version of these models was formulated in the late 2000, when Martin Cederwall using the pure spinor superfield formalism achieved to construct a pure spinor action for these theories, which unlike the previously mentioned approaches, this does not require to impose any constraint by hand, provides a full description of each model (in the BV sense) and the equations of motion coming from the corresponding action principle are supersymmetric. In this work we will explain all the background required to understand the construction of this action. For this purpose, we will start with the D=10 (abelian) SYM theory in its component and superspace formulations. We will use the action of the on-shell formulation to quantize the theory via the Batalin-Vilkovisky framework. We will move to D=11 supergravity and study its component and superspace formulations. Then we will show that we can obtain the same physical spectrum of D = 10 SYM (D = 11 SG) by studying the D = 10 (D = 11) superparticle in the light-cone gauge. In order to have a covariant quantization of these models, we will introduce the D = 10 (D = 11) pure spinor superparticle, which possesses the usual pure spinor BRST operator (Q = λD). It will turn out that the cohomology of this operator will coincide with the linearized D = 10 SYM (D = 11 SG) theory after being quantized via BV-formalism. This result will introduce naturally the idea of constructing pure spinor actions. Finally, we will explain how the pure spinor superfield framework arises in this context and how we can use it to construct manifestly supersymmetric actions for D = 10 SYM and D = 11 SG.
Vibrational Characteristics of AGARD 445.6 Wing in Transonic Flow

This paper presents the application of Computational Fluid Dynamics (CFD) and Fluid Structure Interaction in ANSYS to do vibrational analysis on an aircraft wing in transonic region. A simulation study is conducted on a wing by modelling it in a solid modelling software. Further CFD analysis is performed at different Mach numbers to identify pressure variations at different locations on the wing. Transient structural analysis is carried out to study the variations in displacement of the wing with time. The post processing is done for determining the structural frequency and thereby to establish the flutter boundary in the transonic range.
Zur Histomorphometrie der Zottenvaskularisation von Plazenten diabetischer Mütter

Die histologischen Veränderungen in Plazenten diabetiseher Mütter sind uneinheitlich. Obwohl charakteristische morpho logische Zeichen fehlen, gibt es doch Alterationen, die bei Diabetes gehäuft beobachtet werden. Dies trifft insbesondere für die Fälle zu, bei denen ein schwerer Diabetes mit schlechter Stoffwechselführung während der Gravidität vor liegt