Miracle-dz/UniFAR-FTUs huggingface dataset:
A Survey of Application and Key Techniques for Mobile Crowdsensing

Mobile crowdsensing (MCS) uses ubiquitous smart devices and network access technology to migrate sensing tasks from a centralized platform to a distributed computing terminal across time and space and provides new approaches for solving large-scale, diversified, and complex sensing problems. MCS research is of great importance and has attracted wide attention from researchers. Accordingly, this article summarizes the current research status of MCS. First, the typical applications of MCS are summarized. Then, the research status of key technologies, such as task allocation, incentivizing, data transmission, quality assurance, and evaluation methods, is considered. Finally, future research directions of MCS are given to provide a reference for in-depth MCS research.
Boundedness in a fully parabolic chemotaxis system with nonlinear diffusion and sensitivity, and logistic source

In this paper we study the zero-flux chemotaxis-system \begin{equation*} \begin{cases} u_{ t}=\nabla \cdot ((u+1)^{m-1} \nabla u-(u+1)^\alpha \chi(v)\nabla v) + ku-\mu u^2&x\in \Omega, t>0, \\ v_{t} = \Delta v-vu&x\in \Omega, t>0,\\ \end{cases} \end{equation*} $\Omega$ being a bounded and smooth domain of $\mathbb{R}^n$, $n\geq 1$, and where $m,k \in \mathbb{R}$, $\mu>0$ and $\alpha<\frac{m+1}{2}$. For any $v\geq 0$ the chemotactic sensitivity function is assumed to behave as the prototype $\chi(v) = \frac{\chi_0}{(1+av)^2}$, with $a\geq 0$ and $\chi_0>0$. We prove that for nonnegative and sufficiently regular initial data $u(x,0)$ and $v(x,0),$ the corresponding initial-boundary value problem admits a global bounded classical solution provided $\mu$ is large enough.
Damp‐heat degradation and repair of oxide‐passivated silicon

SiO2‐passivated Si degrades when exposed to a ‘damp‐heat’ atmosphere of 85% relative humidity and 85 °C. We find the effective surface recombination velocity at the SiO2/Si interface of phosphorus‐diffused (111) Si to increase from 2200 to 11 000 cm/s after 7 days of damp‐heat exposure. This degradation is of concern to many high‐efficiency solar cells, which are manufactured from SiO2‐passivated Si with phosphorus‐diffused (111) facets at the front surface, and which must withstand 1000 h of damp‐heat exposure during reliability testing. Our experiments indicate that the damp‐heat exposure causes (i) absorption of H2O into the SiO2, (ii) an increase in the concentration of H at the SiO2/Si interface, (iii) a latent source of degradation that continues after samples are returned to room conditions, and (iv) SiO2/Si interface damage that can be repaired by a short anneal at 300 °C in N2. The results of these experiments are discussed in relation to the various mechanisms that might underlie damp‐heat degradation of SiO2/Si interfaces.
Adaptive Interpolation Strategies in Derivative-Free Optimization: a case study

Derivative-Free optimization (DFO) focuses on designing methods to solve optimization problems without the analytical knowledge of gradients of the objective function. There are two main families of DFO methods: model-based methods and direct search methods. In model-based DFO methods, a model of the objective function is constructed using only objective function values, and the model is used to guide the computation of the next iterate. Natural questions in this class of algorithms include how many function evaluations should be used to construct the model? And, should this number be fixed, or adaptively selected by the algorithm? In this paper, we numerically examine these questions, using Hare and Lucet's Derivative-Free Proximal Point (DFPP) algorithm [Hare, Lucet, 2014] as a case study. Results suggest that the number of function evaluations used to construct the model has a huge impact on algorithm performance, and adaptive strategies can both improve and hinder algorithm performance.
Preperiodic points for quadratic polynomials over cyclotomic quadratic fields

Given a number field $K$ and a polynomial $\varphi(z) \in K[z]$ of degree at least 2, one can construct a finite directed graph $G(\varphi,K)$ whose vertices are the $K$-rational preperiodic points for $f$, with an edge $\alpha \to \beta$ if and only if $\varphi(\alpha) = \beta$. Restricting to quadratic polynomials, the dynamical uniform boundedness conjecture of Morton and Silverman suggests that for a given number field $K$, there should only be finitely many isomorphism classes of directed graphs that arise in this way. Poonen has given a conjecturally complete classification of all such directed graphs over $\mathbb{Q}$, while recent and ongoing work of the author, Faber, Krumm, and Wetherell has provided a detailed study of this question for all quadratic extensions of $\mathbb{Q}$. In this article, we give a conjecturally complete classification like Poonen's, but over the cyclotomic quadratic fields $\mathbb{Q}(\sqrt{-1})$ and $\mathbb{Q}(\sqrt{-3})$. The main tools we use are dynamical modular curves and results concerning quadratic points on curves.
A new 3-dimensional receiver operating characteristic curve for detection performance analysis

Target detection for remotely sensed imagery has been invasively researched for decades. Many detection algorithms are designed and claimed to be outperform others. In order to make an objective comparison, two issues need to be solved. The first one is to have standardized data sets with accurate ground truth, and the second one is to use objective performance analysis techniques. The Receiver Operating Characteristic (ROC) curve is one of the most recognized tools for detection performance analysis. It is based on binary hypothesis test approach. First it constructs two hypothesis distributions (null and alternative hypotheses) and then draws the ROC curve by calculating all the possible detection probability and false-alarm probability pairs. The larger area under the curve means the better detection performance of the algorithm. But one issue is rarely discussed. In ROC analysis, the alternative hypothesis means target exists, but we seldom discuss how much target is presented. In this paper, we include target abundance as the third dimension to form 3-Dimension ROC. The proposed technique can be used to analyze the performance of detection algorithms or the sensor instruments from the different point of views. It can perform the detection probability versus false-alarm probability test as the original ROC, and it can also be use to estimate the minimum target abundance the algorithm can detect.
Design of Real-Valued Wideband Beamformers Using an Adaptive-Array-Theory-Inspired WLS: Theory and Algorithm

The weighted least squares (WLS)-based beamformer design can achieve flexible beampattern control via adjusting the WLS weighting function inspired by the adaptive array theory (AAT). Nevertheless, the weighting function is conventionally adjusted in an ad hoc way, and precise beampattern control cannot be guaranteed. Although an analytical solution for the weighting function adjustment was proposed very recently, it is only applicable to complex-valued narrowband beamformers. In some applications such as acoustic/seismic array processing, however, real-valued wideband beamformers are required, since acoustic/seismic signals are usually unmodulated, real-valued and wideband. This paper studies the theory and design of real-valued wideband beamformers using an AAT-inspired WLS, which can achieve precise wideband beampattern control. The main contributions of this paper include: i) we theoretically prove the existence of the WLS weighting function for the real-valued wideband beamformers to achieve precise control of wideband beampatterns, and derive the corresponding analytical solutions; ii) we provide the insights into the impact of the weighting function on the cost function, which is useful to find the optimum solution for the weighting function among multiple feasible solutions; and iii) we propose an algorithm for the design of real-valued wideband beamformers using the proposed AAT-inspired WLS, which does not require to fine-tune any user parameters, and can guarantee precise control of wideband beampatterns as demonstrated by the simulation results.
A Sextic with 35 Cusps

Recently, W. Barth and S. Rams discussed sextics with up to 30 $A_2$-singularities (also called cusps) and their connection to coding theory [math.AG/0403018]. In the present paper, we find a sextic with 35 cusps within a four-parameter family of surfaces of degree 6 in projective three-space with dihedral symmetry $D_5$. This narrows the possibilities for the maximum number $\mu_{A_2}(6)$ of $A_2$-singularities on a sextic to $35 \le \mu_{A_2}(6) \le 37$. To construct this surface, we use a general algorithm in characteristic zero for finding hypersurfaces with many singularities within a family.
A new class of fuzzy spaces with classical limit

We present a new type of matrix regularization, which is based on matrix-valued functions defined on a cylinder. If non-commutative coordinates of a fuzzy space are defined by a regularization of such functions, we show that a classical limit for the fuzzy spaces exists, when the matrix-valued functions nearly commute. In this case, the classical limit of the fuzzy space is a manifold, which is composed of coordinate patches that are defined by the diagonal entries of the diagonalized matrix-valued functions. As applications, an interpolation for direct sums of fuzzy spaces is described and a fuzzy string vertex with classical limit, i.e. a surface interconnecting three circles, is constructed.
Multi-frequency identification of defects in conducting media

An eddy currents based procedure for the 3D image reconstruction of defects in metallic plates from multi-frequency data is presented. In particular, we exploit the collection of data at different probe positions as well as at different excitation frequencies in order to improve the amount of information content, the accuracy of the inverse methodology and its robustness against the experimental noise. The identification tool we developed, exploits the geometric A − χ formulation for the solution of the eddy-current forward problem together with a full nonlinear iterative inversion algorithm based on the total variation regularization.
GENERATION OF SMALL-SCALE IRREGULARITIES IN THE EQUATORIAL ELECTROJET.

A theory that accounts for the generation of short-wavelength irregularities in the equatorial electrojet for an electron drift velocity below the ion-acoustic speed is presented. Long-wavelength (tens of meters) horizontally propagating waves driven unstable by the ambient ionization density gradient are found not to steepen very much, even though they are nondispersive. However, the local vertical velocity and horizontal density gradient associated with these waves are capable of generating the meter-wavelength obliquely propagating irregularities detected in radar observations.
Boundary effects in Stokes flow

An integral-equation approach is used to calculate the first-order effect of the proximity of a boundary on the Stokes resistance of a body. It is shown, that this approach gives both a simple derivation of the modified Stokes resistance and a method of investigating the accuracy of the final result. The problem of two settling particles is also considered briefly.
Determining Generic Point Configurations From Unlabeled Path or Loop Lengths

Let $\mathbf{p}$ be a configuration of $n$ points in $\mathbb{R}^d$ for some $n$ and some $d \ge 2$. Each pair of points defines an edge, which has a Euclidean length in the configuration. A path is an ordered sequence of the points, and a loop is a path that has the same endpoints. A path or loop, as a sequence of edges, also has a Euclidean length. In this paper, we study the question of when $\mathbf{p}$ will be uniquely determined (up to an unknowable Euclidean transform) from a given set of path or loop lengths. In particular, we consider the setting where the lengths are given simply as a set of real numbers, and are not labeled with the combinatorial data describing the paths or loops that gave rise to the lengths. Our main result is a condition on the set of paths or loops that is sufficient to guarantee such a unique determination. We also provide an algorithm, under a real computational model, for performing a reconstruction of $\mathbf{p}$ from such unlabeled lengths. To obtain our results, we introduce a new family of algebraic varieties which we call the unsquared measurement varieties. The family is parameterized by the number of points $n$ and the dimension $d$, and our results follow from a complete characterization of the linear automorphisms of these varieties for all $n$ and $d$. The linear automorphisms for the special case of $n = 4$ and $d = 2$ correspond to the so-called Regge symmetries of the tetrahedron.
Comparison of Nonparametric Components in Two Partially Linear Models

In this article, we are concerned with whether the nonparametric functions are parallel from two partial linear models, and propose a test statistic to check the difference of the two functions. The unknown constant α is estimated by using moment method under null models. Nonparametric functions under both null and full models are estimated by using local linear method. The asymptotic properties of parametric and nonparametric components are derived. The test statistic under the null hypothesis is calculated and shown to be asymptotically normal.
A Wasserstein Distance-Based Distributionally Robust Chance-Constrained Clustered Generation Expansion Planning Considering Flexible Resource Investments

This paper proposes a distributionally robust chance-constrained (DRCC) model for the clustered generation expansion planning (CGEP) of power systems. The proposed two-stage model minimizes the first-stage total cost along with the second-stage expected penalty cost with the worst-case probability distribution of renewable energy generation. A unit commitment model with flexibility constraints is embedded into the planning model, and the uncertainty is modeled via a Wasserstein distance (WD)-based ambiguity set. Demand-side resources (DSR) and concentrating solar power (CSP) plants are considered as candidates in the DRCC-CGEP model to enhance system flexibility, and the solution efficiency is improved through unit clustering. Furthermore, based on strong duality theory along with affine decision rule and conditional-value-at-risk approximation method, the proposed planning model is reformulated as a tractable mixed-integer linear programming problem. Numerical results show that the proposed WD-based DRCC-CGEP model is effective in improving the economics of the planning decisions while ensuring system reliability and maintaining computational efficiency.
Deformation of algebraic cycle classes in characteristic zero

We study a formal deformation problem for rational algebraic cycle classes motivated by Grothendieck's variational Hodge conjecture. We argue that there is a close connection between the existence of a Chow-K\"unneth decomposition and the existence of expected deformations of cycles. This observation applies in particular to abelian schemes.
On nature and structure of atmospheric circulation anomalies in opposite seasons

In this paper, we consider circulation anomalies obtained in the model of atmospheric general circulation when incoming short wave radiation changes and the initial state anomalies are given. We also consider circulation differences during the years of high and low moisture content in the atmosphere, using the reanalysis data. Using the global model, we studied such winter and summer circulation anomalies that result from the attenuation of winter radiation forcing and accordingly reduction in summer radiation atmosphere heating. In the other series of experiments the joint 'atmosphere-soil' initial moisture anomalies in transitional seasons (autumn, spring) are formed by using a hemisphere model and their effects on the subsequent structure of the circulation anomalies are investigated. It turned out that these anomalous numerical experiments different both in the boundary and initial conditions model the similar anomalies. Namely, in transition in the annual variation to winter circulation (or in winter) pressure long-wave troughs and ridges are damped, in transition to summer circulation (or in summer) west-east transport at the high latitudes is attenuated by the modelled anomalies.
State Constrained Optimization with Partial Differential Equations via Generalized Gradients

We consider optimization problems constrained by partial differential equations (PDEs) with additional constraints placed on the solution of the PDEs. We develop a general and versatile framework using infinite-valued penalization functions and Clarke subgradients and apply this to problems with box constraints as well as more general constraints arising in applications, such as constraints on the average value of the state in subdomains. The framework also allows for problems with discontinuous data in the constraints. We present numerical results of this algorithm for the elliptic case and compare with other state-constrained algorithms.
Contributions of Multibody Dynamics to Space Flight: A Brief Review

A brief historical review is given of developments in multibody dynamics that led to the successful prediction of attitude motions of space vehicles. The important role of methods that simplified the formulation of equations of motion of complex spacecraft is pointed out. Developments in modeling flexible bodies undergoing large overall motion are highlighted. Factors reducing computer simulation time, such as the use of symbol manipulation, recursive formulation, and parallel processing algorithms, are outlined, and real-time computation is exemplified. Applications of multibody dynamics to space flight range from solar panel deployment to servicing of satellites by the shuttle manipulator arm, construction of the space station, and more. Although the details of these examples remain unpublished in many company and agency reports, a few representative applications of multibody dynamics to spacecraft simulations are recalled.
CONNES DISTANCE BY EXAMPLES: HOMOTHETIC SPECTRAL METRIC SPACES

We study metric properties stemming from the Connes spectral distance on three types of non-compact non-commutative spaces which have received attention recently from various viewpoints in the physics literature. These are the non-commutative Moyal plane, a family of harmonic Moyal spectral triples for which the Dirac operator squares to the harmonic oscillator Hamiltonian and a family of spectral triples with the Dirac operator related to the Landau operator. We show that these triples are homothetic spectral metric spaces, having an infinite number of distinct pathwise connected components. The homothetic factors linking the distances are related to determinants of effective Clifford metrics. We obtain, as a by-product, new examples of explicit spectral distance formulas. The results are discussed in detail.
PSFNet: A Deep Learning Network for Fake Passport Detection

Passport security feature classification has always been an important issue in border checks. Current manual methods struggle to achieve satisfactory results in terms of consistency and stability for security features with high similarity. For this reason, this study designs and develops a deep learning-based passport security feature classification model that can identify similar security features. The proposed model is based on the ShuffleNet v2, and its network structure is further optimized by two aspects for our task. Firstly, we embed pixel attention in the model to enable the network to better focus on important features with discriminatory power. Secondly, we introduce focal loss to relieve the overfitting problem caused by data imbalance. Finally, the superiority of the proposed classification algorithm is verified with the constructed passport security features data. The classification accuracy of the proposed algorithm is enhanced by 0.8%. The experimental results show that the classification accuracy is as high as 95.5%.
A Technique for the Study of Stellar Convection: The Visible Solar Flux Spectrum

Convective motions in the solar photosphere produce line asymmetries that are traditionally studied using line bisectors observed with very high spectral resolution and signal‐to‐noise ratio. We study relative line‐core shifts as a surrogate for bisectors, using the most current laboratory line positions of 298 Fe i lines in the Sun’s visible flux spectrum and a new technique for determining line position. We show that this technique can be applied at significantly lower spectral resolutions and signal‐to‐noise ratios than has been done using bisectors. These line‐core shifts show a clear dependence on both line strength and wavelength. The possibility of a dependence on the lower excitation energy is also examined.
Orthogonal Genetic Algorithm and its Application in Function Optimization

Traditional genetic algorithm trapped into the local minimum easily. Therefore, based on a simple genetic algorithm and combine the base ideology of orthogonal test then applied it to the population initialization, crossover operator, as well as the introduction of adaptive orthogonal local search to prevent local convergence to form a new orthogonal evolutionary algorithm. Through the series of numerical experiments, proved the efficiency of the new algorithm.
Towards $A+B$ theory in conifold transitions for Calabi–Yau threefolds

For projective conifold transitions between Calabi-Yau threefolds $X$ and $Y$, with $X$ close to $Y$ in the moduli, we show that the combined information provided by the $A$ model (Gromov--Witten theory in all genera) and $B$ model (variation of Hodge structures) on $X$, linked along the vanishing cycles, determines the corresponding combined information on $Y$. Similar result holds in the reverse direction when linked with the exceptional curves.
On wave propagation in a random micropolar thermoelastic medium, second moments, and associated Green’s tensor

The couple stress theory developed by Eringen comprises granular materials as also composite fibrous materials. As such, micropolar materials present an inclusive model of composite materials. This article endeavors to study aspects of wave propagation in a random weakly thermal micropolar elastic medium. The smooth perturbation technique has been employed. The classical thermoelasticity has been used. Six different types of waves have been observed to propagate in the random interacting medium. Dispersion equations have been derived. The effects due to random variations of micropolar elastic and thermal parameters have been observed. Change of phase speed occurs on account of randomness. Attenuation coefficients for high-frequency waves have been computed. Second moment properties have been discussed with application to wave propagation in the random micropolar elastic medium. 36 + 1 components of the associated Green’s tensor have been computed. Integrals involving correlation functions have been transformed to radial forms. A special type of correlation function has been used to approximately measure effects of random variations of parameters.
Differential forms, Fukaya $A_\infty$ algebras, and Gromov–Witten axioms

Consider the differential forms $A^*(L)$ on a Lagrangian submanifold $L \subset X$. Following ideas of Fukaya-Oh-Ohta-Ono, we construct a family of cyclic unital curved $A_\infty$ structures on $A^*(L),$ parameterized by the cohomology of $X$ relative to $L. $ The family of $A_\infty$ structures satisfies properties analogous to the axioms of Gromov-Witten theory. Our construction is canonical up to $A_\infty$ pseudoisotopy. We work in the situation that moduli spaces are regular and boundary evaluation maps are submersions, and thus we do not use the theory of the virtual fundamental class.