Miracle-dz/UniFAR-FTUs huggingface dataset:
Aeroacoustics of wall-bounded turbulent flows

Direct numerical simulations of turbulent plane Poiseuille and Couette flow are used to study fluctuating wall pressure and shear stress. For both flows the wave-number–frequency spectra are found to be nonzero in the limit of zero wave number, which has significant implications for theoretical work. Peaks in the spectra are consistent with convective phenomena, and typical convection speeds are derived for both cases. The sensitivity of the results to Reynolds number and numerical parameters is discussed.
Direct Numerical Simulation of Spatial Transition to Turbulence Using Fourth-Order Vertical Velocity Second-Order Vertical Vorticity Formulation

A highly accurate algorithm has been developed to study the process of spatial transition to turbulence. The algorithmic details of the direct numerical simulation (DNS) of transition to turbulence in a boundary layer based on a formulation in terms of vertical velocity and vertical vorticity are presented. Issues concerning the boundary conditions are discussed. The linear viscous terms are discretized using an implicit Crank? Nicholson scheme, and a low-storage Runge? Kutta method is used for the nonlinear terms. For the spatial discretization, fourth-order compact finite differences have been used, as these have been found to have better resolution compared to explicit differencing schemes of comparable order. The number of grid points that are needed per wavelength is close to the theoretical optimum for any numerical scheme. The resulting time-discretized fourth-order equations are split up into two second-order equations, resulting in Helmholtz- and Poisson-type equations. The boundary conditions for the Laplacian of the vertical velocity are determined using an influence matrix method. A robust multigrid algorithm has been developed to solve the resulting anisotropic elliptical equations. For the outflow boundary, a buffer domain method, which smoothly reduces the disturbances to zero, in conjunction with parabolization of the Navier? Stokes equations has been used. The validation of the results for the DNS solver is made both for linear and weakly nonlinear cases.
Decentralized output feedback stabilization of a class of nonlinear interconnected systems

The problem of decentralized output feedback stabilization of a class of nonlinear interconnected systems is considered. On the basis of the linear-quadratic design, a sufficient condition for the existence of the decentralized output feedback control of the problem is presented. An estimation of the associated stability domain is also given. An application to the decentralized control of a large-scale telescope is presented to illustrate the use of the results. >
Visualizing Multivariate Dependencies with Association Chain Graphs

In a recent paper, a new type of graph to visualize the results from graphical models was proposed. Association chain graphs (ACGs) provide a richer visualization than conventional graphs (directed acyclic and recursive regression graphs) if the data can be described with only a small number of parameters. ACGs display not only which associations reach statistical significance, but also the magnitude of associations (confidence intervals for statistical main effects) as the contrast color to the background color of the graph. In this paper, the ACG visualization is extended especially for the case where all variables are binary by illustrating their relative frequencies. This shows the degrees of associations not only on the individual (as expressed by odds ratios or other indexes of association) but also on the community level. We applied the approach to an extensive example of birth and childhood factors for the onset of affective mental disorders using data from the EDSP (Early Developmental Stages of .
Precision Agriculture Using Soil Sensor Driven Machine Learning for Smart Strawberry Production

Ubiquitous sensor networks collecting real-time data have been adopted in many industrial settings. This paper describes the second stage of an end-to-end system integrating modern hardware and software tools for precise monitoring and control of soil conditions. In the proposed framework, the data are collected by the sensor network distributed in the soil of a commercial strawberry farm to infer the ultimate physicochemical characteristics of the fruit at the point of harvest around the sensor locations. Empirical and statistical models are jointly investigated in the form of neural networks and Gaussian process regression models to predict the most significant physicochemical qualities of strawberry. Color, for instance, either by itself or when combined with the soluble solids content (sweetness), can be predicted within as little as 9% and 14% of their expected range of values, respectively. This level of accuracy will ultimately enable the implementation of the next phase in controlling the soil conditions where data-driven quality and resource-use trade-offs can be realized for sustainable and high-quality strawberry production.
Stability of self‐tuning control based on Lyapunov function

The overall stability of a self‐tuning controller for discrete‐time systems is proved by using the Lyapunov function in this paper, for minimum and a class of non‐minimum phase systems. The self‐tuning controller utilizes a recursive estimate algorithm for the controller parameters based on the generalized minimum variance criterion. Previously, the stability had been proved in the case of minimum phase systems. A new type of self‐tuning controller for the discrete‐time system with delay in control input is also studied which is named the generalized minimum variance criterion‐β equivalent control, and its stability is proved. The simulation is done to evaluate the performance of the proposed self‐tuning controller. Copyright © 2008 John Wiley & Sons, Ltd.
Inferences on the solar envelope with high-degree modes

We investigate the structure of the Sun by helioseismic inversion of a set of p-mode frequencies which includes new precise observations of modes with high degree ( l< 1000) obtained from the MDI instrument on the SOHO satellite (Rhodes et al. 1998). Such data have the potential to improve the resolution of the solar structure in the near-surface region, to provide detailed tests of the equation of state and constrain the envelope helium abundance. In order to suppress the uncertainties in the treatment of the surface layers in helioseismic inversion procedures, we introduce here the use of a new surface term, developed on the basis of higher-order asymptotic theory of acoustic modes and suitable for the handling of high-degree mode frequencies.
Estimation of source separation with an array of arbitrary shape

Analytical expressions are obtained for the Cramer-Rao bound on average bearing and angular separation of two independent far-field sources radiating narrowband Gaussian noise. It is shown that all relevant features of array geometry are summarized by the conventional beam pattern function. For sources separated by less than the main lobe width of the beam pattern, the significant properties of the beam pattern are summarized by two simple geometrical factors. For small source separations lack of prior knowledge of source power levels seriously degrades performance. <<ETX>>
Estrogenic Effect Mechanism and Influencing Factors for Transformation Product Dimer Formed in Preservative Parabens Photolysis

The environmental transformation and health effects of endocrine disruptors (EDCs) need urgent attention, particularly the formation of transformation products with higher toxicity than parent EDCs. In this paper, an important transformation product dimer (short for ethyl 4-hydroxy-3-(2-((4-hydroxybenzoyl) oxy) ethyl) benzoate) with estrogenic activity was investigated and detected in the photolysis of preservative ethyl-paraben (EPB) dissolved in actual water. The environmental factors, such as the higher initial concentration of EPB, the stronger optical power and the lower pH could stimulate the formation of the dimer. Simultaneously, the interaction of multiple environmental factors was significant, especially the initial concentration and pH using the response surface methodology. Furthermore, the relationship between the environmental factors and the formation of the product dimer was further explained and the empirical model equation was built for predicting the amount of dimer in actual water. Quantum chemical and toxicological calculations showed the estrogenic effect mechanism of the product dimer and it was revealed further that the hydrogen bonds of the dimer and ERα proteins (ARG-394, Glu-353, His-524, GYY-521) were formed, with a lowest binding energy of −8.38 Kcal/mol during molecular docking. In addition, the health effect risk of the product dimer was higher than the parent compound in the blood, cardiovascular system, gastrointestinal system, kidney and liver. In short, the present study was of great significance for the transformation product in pollution control and health effects in the photolysis of EDCs.
INTERNATIONAL CONFERENCE ON RELATIVISTIC THEORIES OF GRAVITATION, LONDON, 1965, VOLUME I.

Abstract : About 300 delegates from all parts of the world met from the 1st to the 10th July in London at Imperial College for the 5th International Conference on relativity. Most interesting discussions on the question of gravitational collapse were held. Considerably more is now known about bodies collapsing under their own gravitational stresses than a year ago. The equations of collapse have been integrated numerically, notably by Michael May, and it is found that certain kinds of matter can, instead of undergoing a catastrophic collapse, 'bounce'. The final state becomes one of ultimate dispersion. Whether such behaviour can occur in practice is still in doubt. The great interest in collapsing bodies has been caused by the discovery of quasars, and it seemed for a considerable time that the collapsing bodies and the quasars were identical. The large amounts of energy radiated by quasers may well require a source of energy liberating a larger fraction of the mass than nuclear reaction can do, and the only such possibility seems to be gravitational contraction and collapse. However the rapidly collapsing body suffers from two great defects when providing so much energy. The matter is moving inwards at a high speed, producing an extreme Doppler shift to the red and the extreme concentration produces a strong gravitational field and so a further shift to the red, due to the usual general relativistic effect. (Author)
Probabilistic Techniques for Constraint Satisfaction Problems

Constraint satisfaction problems (CSPs) are at the core of many tasks with direct practical relevance, such as hardware and software verification, planning, and scheduling to name a few. The two main solution paradigms for solving such problems are based on backtrack-style search and local search. However, recently, a new powerful technique, called survey propagation (SP), was introduced. SP can solve certain classes of problem instances with millions of variables and constraints. This discovery raised a question of whether the traditional techniques are the best one can do when tackling large and important constraint satisfaction problems. This dissertation discusses non-traditional approaches to solving CSPs. The techniques we use include probabilistic inference, statistical tools and a combination of systematic and local search. We provide a new derivation of SP based on purely combinatorial insights. Our method also enables us to derive SP-style procedures for a diverse range of constraint satisfaction problems, and provides insights into structure of solution spaces. The second part of the dissertation describes approaches to counting number of solutions of a CSP with the help of Belief Propagation and statistics. We also provide a novel hybrid algorithm for minimizing the number of violated constraints, which employs both systematic and local search, harnessing their complementary strengths. These methods are the most scalable algorithms for certain hard to solve classes of Boolean satisfiability (SAT), model counting (#SAT), and maximum satisfiability (MaxSAT) problems.
Slip effects on the peristaltic flow of a Jeffrey fluid in an asymmetric channel under the effect of induced magnetic field

In the present study, we investigated the effects of slip and induced magnetic field on the peristaltic flow of a Jeffrey fluid in an asymmetric channel. The governing two‐dimensional equations for momentum, magnetic force function and energy are simplified by using the assumptions of long wavelength and low but finite Reynolds number. The reduced problem has been solved by Adomian decomposition method (ADM) and closed form solutions have been presented. Further, the exact solution of the proposed problem has also been computed and the mathematical comparison shows that both solutions are almost similar. The effects of pertinent parameters on the pressure rise per wavelength are investigated using numerical integration. The expressions for pressure rise, friction force, velocity, temperature, magnetic force function and the stream lines against various physical parameters of interest are shown graphically. Moreover, the behavior of different kinds of wave shape are also discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Geometric group actions on trees

We define geometric group actions on R-trees, as dual to a measured foliation on a 2 complex with some finiteness and injectivity properties. We prove that an action is nongeometric if and only if it is a nontrivial strong limit in the sense of Gillet-Shalen. We give a simple new construction of the Bass-Serre tree of a graph of groups, and we show that a simplicial action is geometric if and only if edge groups are finitely generated. We prove that geometric actions with trivial edge stabilizers have finitely many orbits of branch points, and finite rank. Introduction. An R-tree is an arcwise connected metric space in which every arc is isometric to an interval of R. See for instance (Shal, Sha2, Mor) for historical remarks, references and motivation. It is well-known that codimension one measured foliations (or laminations) on compact manifolds have strong connections with group actions on R-trees
Effective results for unit equations over finitely generated integral domains

Abstract Let A ⊃ ℤ be an integral domain which is finitely generated over ℤ and let a,b,c be non-zero elements of A. Extending earlier work of Siegel, Mahler and Parry, in 1960 Lang proved that the equation (*) aϵ +bη = c in ϵ, η ∈ A* has only finitely many solutions. Using Baker's theory of logarithmic forms, Győry proved, in 1979, that the solutions of (*) can be determined effectively if A is contained in an algebraic number field. In this paper we prove, in a quantitative form, an effective finiteness result for equations (*) over an arbitrary integral domain A of characteristic 0 which is finitely generated over ℤ. Our main tools are already existing effective finiteness results for (*) over number fields and function fields, an effective specialization argument developed by Győry in the 1980's, effective results of Hermann (1926) and Seidenberg (1974) on linear equations over polynomial rings over fields, and similar such results by Aschenbrenner, from 2004, on linear equations over polynomial rings over ℤ. We prove also an effective result for the exponential equation aγ1v1···γsvs+bγ1w1 ··· γsws=c in integers v1,…,ws, where a,b,c and γ1,…,γs are non-zero elements of A.
The association between low virulence organisms in different locations and intervertebral disc structural failure: A meta‐analysis and systematic review

Many factors may trigger intervertebral disc (IVD) structural failure (intervertebral disc degeneration (IDD) and endplate changes), including inflammation, infection, dysbiosis, and the downstream effects of chemical factors. Of these, microbial diversity in the IVD and elsewhere in the body has been considered as one of the potential reasons for disc structural failure. The exact relationships between microbial colonization and IVD structural failure are not well understood. This meta‐analysis aimed to investigate the impact of microbial colonization and its location (such as skin, IVD, muscle, soft tissues, and blood) on IVD structural failure and corresponding low back pain (LBP) if any. We searched four online databases for potential studies. The potential relationships between microbial colonization in different sample sources (such as skin, IVD, muscle, soft tissues, and blood) and IDD and endplate change were considered as primary outcomes. Odds ratio (OR) and 95% confidence intervals (CI) for direct comparisons were reported. Grading of Recommendations Assessment, Development and Evaluation (GRADE) scale was used to assess the quality of evidence. Twenty‐five cohort studies met the selection criteria. Overall pooled prevalence of microbial colonization in 2419 patients with LBP was 33.2% (23.6%–43.6%). The pooled prevalence of microbial colonization in 2901 samples was 29.6% (21.0%–38.9%). Compared with the patients without endplate change, the patients with endplate changes had higher rates of microbial colonization of disc (OR = 2.83; 95% CI = 1.93–4.14; I2 = 37.6%; p = 0.108). The primary pathogen was Cutibacterium acnes which was present in 22.2% of cases (95% CI = 13.3%–32.5%; I2 = 96.6%; p = 0.000). This meta‐analysis and systematic review found low‐quality grade evidence for an association between microbial colonization of disc with endplate changes. The primary pathogen was C. acnes. Due to lack of enough high‐quality studies and methodological limitations of this review, further studies are required to improve our understanding of the potential relationships and mechanisms of microbiota, dysbiosis, IVD colonization and IVD structural failure.
Self-organized criticality of a simple integrate-and-fire neural model

We consider a simple integrate-and-fire neural model without synaptic plasticity. In this model, the membrane potential propagates to the nearest neighbor neurons when that potential is greater than a threshold value. When a neuron is fired, the propagating potential is leaky. Therefore, the sum of the received potential is less than the presynaptic potential. We simulated this simple model on a fully-connected network. We identified the critical membrane strength, Jc = 4.71(1). At the critical membrane strength, we observed that the probability distribution function of the avalanche shows a power law, P(s) ≈ s−τ, with the critical exponent τ = 1.414(5). The lifetime of the avalanche also showed a power law. The power law behaviors imply that this model shows self-organized criticality.
From animal collective behaviors to swarm robotic cooperation

ABSTRACT The collective behaviors of animals, from schooling fish to packing wolves and flocking birds, display plenty of fascinating phenomena that result from simple interaction rules among individuals. The emergent intelligent properties of the animal collective behaviors, such as self-organization, robustness, adaptability and expansibility, have inspired the design of autonomous unmanned swarm systems. This article reviews several typical natural collective behaviors, introduces the origin and connotation of swarm intelligence, and gives the application case of animal collective behaviors. On this basis, the article focuses on the forefront of progress and bionic achievements of aerial, ground and marine robotics swarms, illustrating the mapping relationship from biological cooperative mechanisms to cooperative unmanned cluster systems. Finally, considering the significance of the coexisting-cooperative-cognitive human-machine system, the key technologies to be solved are given as the reference directions for the subsequent exploration.
Heuristic random optimizer-version II

This work presents the search logic of a multivariable optimizer that is a combination of heuristic rules and random perturbations, and demonstrates its performance on classic and new test cases. One of the neural network applications had 80 decision variables. The improved Heuristic Random Optimization (HRO-II) strategy is shown to accommodate surface discontinuities, handle hard constraints, to have a high probability of finding a global optimum, and to be scale independent.
Broad-band dual-polarized single microstrip patch antenna with high isolation and low cross polarization

This paper presents a new design of a broad-band dual-polarized single microstrip patch antenna with highly decoupled input ports and low cross-polarization (XP) radiation. A prototype of the proposed antenna with center frequency at 1800 MHz is presented. Both the dual linear polarizations have 10-dB return-loss impedance bandwidths greater than 14% and high decoupling between the two input ports (S/sub 21/ less than -40 dB across the entire bandwidths) is obtained. Moreover, the XP radiation in the principal planes of the dual linear polarizations is seen to be less than -20 dB.
Outcome Evaluation of Distal Femoral Fractures Following Surgical Management: A Retrospective Cohort Study

Background: Distal femur fractures are challenging in surgical management as the outcome is crucial for restoring the biomechanical stability and longitudinal axis of the leg and function of the knee joint. Methods: A retrospective review of all distal femoral fractures treated in a level I trauma center over a decade was performed. The radiographs were reviewed for fracture entity, osseous healing, implant failure, mechanical axis, and degenerative joint changes. Clinical outcome was reviewed regarding postoperative complications and postoperative range of motion of the knee joint. Results: 130 patients who were managed with screw fixation (n = 35), plating systems (n = 92) or intramedullary nailing systems (n = 3) remained for evaluation. Mean follow up was 26 months. Clinical outcome was significantly better for flexion degrees following screw fixation (p = 0.009). Delayed fracture union (p = 0.002) or non-union (p = 0.006) rates were significantly higher in plate osteosynthesis. Mild pathologic deformity for varus and valgus collapse was found following plate osteosynthesis. Conclusions: Screw fixation shows fewer postoperative complications than plate fixation and is favored for extra and partial intraarticular distal femur fractures. Plating constructs remain the superior fixation method in complex distal femur fractures but are associated with higher rates of non-union and leg axis deviation.
Galectin functions in cancer-associated inflammation and thrombosis

Galectins are carbohydrate-binding proteins that regulate many cellular functions including proliferation, adhesion, migration, and phagocytosis. Increasing experimental and clinical evidence indicates that galectins influence many steps of cancer development by inducing the recruitment of immune cells to the inflammatory sites and modulating the effector function of neutrophils, monocytes, and lymphocytes. Recent studies described that different isoforms of galectins can induce platelet adhesion, aggregation, and granule release through the interaction with platelet-specific glycoproteins and integrins. Patients with cancer and/or deep-venous thrombosis have increased levels of galectins in the vasculature, suggesting that these proteins could be important contributors to cancer-associated inflammation and thrombosis. In this review, we summarize the pathological role of galectins in inflammatory and thrombotic events, influencing tumor progression and metastasis. We also discuss the potential of anti-cancer therapies targeting galectins in the pathological context of cancer-associated inflammation and thrombosis.