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We prove a representation stability result for the Milnor fiber associated to the pure braid group. Our result connects previous work of Simona Settepenella to representation stability in the sense of Church--Ellenberg--Farb, answering a question of Graham Denham. We also use our result to compute the stable integral homology of the Milnor fiber.

Moduli spaces of bounded local G-shtukas are a group-theoretic generalisation of the function field analogue of Rapoport and Zink’s moduli spaces of p-divisible groups. In this article we generalise some very prominent concepts in the theory of Rapoport-Zink spaces to our setting. More precisely, we define period spaces, as well as the period map from a moduli space of bounded local G-shtukas to the corresponding period space, and we determine the image of the period map. Furthermore, we define a tower of coverings of the generic fibre of the moduli space, which is equipped with a Hecke action and an action of a suitable automorphism group. Finally, we consider the $\ell $ -adic cohomology of these towers.Les espaces de modules de G-chtoucas locaux bornés sont une généralisation des espaces de modules de groupes p-divisibles de Rapoport-Zink, au cas d’un corps de fonctions local, pour des groupes plus généraux et des copoids pas nécessairement minuscules. Dans cet article nous définissons les espaces de périodes et l’application de périodes associés à un tel espace, et nous calculons son image. Nous étudions la tour au-dessus de la fibre générique de l’espace de modules, équipée d’une action de Hecke ainsi que d’une action d’un groupe d’automorphismes. Enfin, nous définissons la cohomologie $\ell $ -adique de ces tours.

We study the Picard–Lefschetz formula for Siegel modular threefolds of paramodular level and prove the weight-monodromy conjecture for its middle degree inner cohomology. We give some applications to the Langlands programme: using Rapoport-Zink uniformisation of the supersingular locus of the special fiber, we construct a geometric Jacquet–Langlands correspondence between $${\text {GSp}}_4$$ GSp 4 and a definite inner form, proving a conjecture of Ibukiyama. We also prove an integral version of the weight-monodromy conjecture and use it to deduce a level lowering result for cohomological cuspidal automorphic representations of $${\text {GSp}}_4$$ GSp 4 .

We show a rigidity theorem for the Seiberg-Witten invariants mod 2 for families of spin 4-manifolds. A mechanism of this rigidity theorem also gives a family version of 10/8-type inequality. As an application, we prove the existence of non-smoothable topological families of 4-manifolds whose fiber, base space, and total space are smoothable as manifolds. These non-smoothable topological families provide new examples of 4-manifolds $M$ for which the inclusion maps $\operatorname{Diff}(M) \hookrightarrow \operatorname{Homeo}(M)$ are not weak homotopy equivalences. We shall also give a new series of non-smoothable topological actions on some spin 4-manifolds., 40 pages, to appear in Compositio Mathematica

In the design optimization of variable stiffness composites, manufacturing constraints imposed by the automated fiber placement technology must be considered. In the present paper, two filters are proposed to address this issue, and they are incorporated into the Shepard interpolation-based design optimization framework developed in our previous studies. The fiber angle arrangement of a composite is represented by a continuous function that interpolates fiber angles at scattered design points. Two filters are appointed for each design point to deal with two typical manufacturing constraints, i.e., fiber curvature and gap/overlap. At each design point, the sensitivity is first filtered in a rectangular region around this point, and by this means the fiber curvature is controlled; then in another rectangular region around this design point, the filtered sensitivities are averaged, and the result is used to update the corresponding design variable. Several numerical examples are investigated, and the results show that the proposed method is effective.

Consider a very general abelian variety $A$ of dimension at least $3$ and an integer $0, Comment: 9 pages

As of today, it still remains a considerable challenge to identify the polyester/cotton fiber category in the textile industry. Based on shape coefficient analysis, a novel comprehensively-designed and appropriately-developed digital cross-section image processing method was proposed to improve the identification accuracy of polyester/cotton fiber. A self-developed microscope image acquisition system was established, so as to digitalize the cross section of fiber. Aimed at the gray scale enhancement, binarization and opening operation, a set of image preprocessing algorithms was developed. Initially, the edge detection algorithm was used to identify the external contour of the cross-section of fiber. Subsequently, the cross section of fiber was separated by watershed segmentation algorithm, and that, the false fiber was removed by area elimination algorithm. Finally, the shape coefficient was calculated to identify polyester/cotton fiber category. The experimental results indicated that the data and results obtained by the newly-designed digital analysis method which is based on shape coefficient in this paper can be used to identify the polyester/cotton fiber category, showing a broad application prospect in textile quality control, including the developments of concerned equipments, methods and standards.

We consider the accuracy of slender body theory in approximating the force exerted by a thin fiber on the surrounding viscous fluid when the fiber velocity is prescribed. We term this the slender body inverse problem, as it is known that slender body theory converges to a well-posed PDE solution when the force is prescribed and the fiber velocity is unknown. From a PDE perspective, the slender body inverse problem is simply the Dirichlet problem for the Stokes equations, but from an approximation perspective, nonlocal slender body theory exhibits high wavenumber instabilities which complicate analysis. Here we consider two methods for regularizing the slender body approximation: spectral truncation and the $\delta$-regularization of Tornberg and Shelley (2004). For a straight, periodic fiber with constant radius $\epsilon>0$, we explicitly calculate the spectrum of the operator mapping fiber velocity to force for both the PDE and the approximations. We show that the spectrum of the original slender body approximation agrees closely with the PDE solution at low wavenumbers but differs at high frequencies, allowing us to define a truncated approximation with a wavenumber cutoff $\sim1/\epsilon$. For both the truncated and $\delta$-regularized approximations, we obtain similar convergence results to the PDE solution as $\epsilon\to0$: a fiber velocity with $H^1$ regularity gives $O(\epsilon)$ convergence, while a fiber velocity with at least $H^2$ regularity yields $O(\epsilon^2)$ convergence. Moreover, we determine the dependence of the $\delta$-regularized error estimate on the regularization parameter $\delta$.

Optical fiber sensing technology has developed rapidly since the 1980s with the development of the optical fiber and fiber optical communication technology. It is a new type of sensing technology that uses light as a carrier and optical fiber as a medium to sense and transmit external signals (measurands). Distributed fiber optical sensors (DFOS) can continuously measure the external physical parameters distributed along the geometric path of the optical fiber. Meanwhile, the spatial distribution and change information of the measured physical parameters over time can be obtained. This technology has unmatched advantages over traditional point-wise and electrical measurement monitoring technologies. This paper summarizes the state-of-the-art research of the application of the distributed optical fiber sensing technology in geo-engineering in the past 10 years, mainly including the advantages of DFOS, the challenges in geo-engineering monitoring, related fundamental theoretical issues, sensing performance of the optical sensing cables, distributed optical fiber monitoring system for geo-engineering, and applications of optical fiber sensing technology in geo-engineering.

In the present paper, we study the (twisted) 3-canonical map of varieties of Albanese fiber dimension one. Based on a theorem about the regularity of direct image of canonical sheaves, we prove that the 3-canonical map is generically birational when the genus of a general fiber of the Albanese map is 2., Comment: 14 pages

In this study, an innovative roller drafting simulation model was proposed to study the straightening process of hooked fibers in the draft zone. Specifically, it could be efficiently used to understand the straightness and arrangement of the individual hooked fiber in the sliver during the drafting process. The drafting process was deeply analyzed by considering the drafting time into the low-speed time, straightening time and high-speed time. In the drafting procedure, the straightening process for four kinds of hooked fiber were divided into 16 cases based on the relationship between their accelerated points and hooked parts. The obtained simulation straightness can quantitatively reveal the influence of drafting ratio and the length of drafting zone on the straightening of hooked fiber and provide theoretical basis for setting the draft parameters. Moreover, the simulated straightness of every drawing process was demonstrated to be close to the actual values. More importantly, the simulated results strongly confirm the theory that normal drafting has an influence on the straightening of hooked fibers. Therefore, the proposed roller drafting model was proved to be rational and can offer effective reference in the further spinning process simulation.

Optical fiber sensor networks (OFSNs) provide powerful tools for large-scale buildings or long-distance sensing, and they can realize distributed or quasi-distributed measurement of temperature, strain, and other physical quantities. This article provides some optical fiber sensor network technologies based on the white light interference technology. We discuss the key issues in the fiber white light interference network, including the topology structure of white light interferometric fiber sensor network, the node connection components, and evaluation of the maximum number of sensors in the network. A final comment about further development prospects of fiber sensor network is presented.

Fiber reinforced materials are used in assorted engineering application and for this reason, new additive manufacturing technologies have been developed for this type of materials. With these technologies, it is possible to construct composite structures with different shapes and desired fiber orientation. Therefore, reinforced composite structures can be designed based on an optimized fiber orientation. Because of it, several works propose different methods to tailor fiber directions. Albeit, the determination of fiber optimized orientation is a problem usually subjected to multiple local minima issues, unless discrete material optimization methods are used. In addition, in these works, usually a linear relation between stress and strain is considered, which limits simulations to small displacements, strains and rotations. Recently, a method named SPIMFO has been developed where the angle is considered a continuous variable and the local minima issues are circumvented. Thus, this work proposes to determine the optimized fiber orientation of a fiber reinforced composite structure by using the SPIMFO method with a constitutive equation in fully nonlinear range based on transversely isotropic neo-Hookean model. A new method to measure the fiber continuity named index of average continuity is proposed and implemented. The results obtained by using the proposed method are compared to results obtained by using a discrete model named NDFO-m, which is proposed in a previous work.

In this paper, applying the weak maximum principle, we obtain the uniqueness results for the hypersurfaces under suitable geometric restrictions on the weighted mean curvature immersed in a weighted Riemannian warped product I × ρ M f n whose fiber M has f -parabolic universal covering. Furthermore, applications to the weighted hyperbolic space are given. In particular, we also study the special case when the ambient space is weighted product space and provide some results by Bochner’s formula. As a consequence of this parametric study, we also establish Bernstein-type properties of the entire graphs in weighted Riemannian warped products.

This paper proposes a method to solve the joint optimization of test node selection and fiber thread connection. The problem is modeled as an integer linear programming problem with two classes of decision variables. The first class of decision variables are composed of the number of parallel fiber threads throughout each potential testing route, the other class of decision variables are imposed just to denote whether a node is decided as a location to place testing equipment. The objective of the joint optimization is to minimize the number of nodes where fiber test equipment based on the optical time domain reflectometer are planned to locate. The objective function is just the sum of the second class of decision variables. Two types of linear constraints are needed. The first type of constraints describes the mutual relation between the two classes of variables, and the other type of constraints are formed to depict the impact of the number of fiber threads mounted within each fiber link on the first class of decision variables. Multiple examples are given to exhibit the advantage of joint optimization over heuristic method.

We consider H\"older continuous cocycles over an accessible partially hyperbolic system with values in the group of diffeomorphisms of a compact manifold $M$. We obtain several results for this setting. If a cocycle is bounded in $C^{1+\gamma}$, we show that it has a continuous invariant family of $\gamma$-H\"older Riemannian metrics on $M$. We establish continuity of a measurable conjugacy between two cocycles assuming bunching or existence of holonomies for both and pre-compactness in $C^0$ for one of them. We give conditions for existence of a continuous conjugacy between two cocycles in terms of their cycle weights. We also study the relation between the conjugacy and holonomies of the cocycles. Our results give arbitrarily small loss of regularity of the conjugacy along the fiber compared to that of the holonomies and of the cocycle., Comment: 24 pages

We determine the structure of the fibered biset functor sending a finite group $G$ to the complex vector space of complex valued class functions of $G$. Previously, it is studied as a biset functor by Bouc and as a $\mathbb C^\times$-fibered biset functor by Boltje and the second author. In this paper, we complete the study by considering the other choices of the fiber group. As a corollary, we obtain a (previously known) set of composition factors of the biset functor of $p$-permutation modules., Comment: 27 pages

It is shown that Liouville foliations of the family of non-Euclidean analogs of Kovalevskaya integrable system on a pencil of Lie algebras have both compact and noncompact fibers. There exists a bifurcation of their compact common level surface into a noncompact one that has a noncompact singular fiber. In particular, this is true for the non-Euclidean $$e(2,1)$$ -analog of the Kovalevskaya case of rigid body dynamics. In the case of nonzero area integral, an effective criterion for existence of a noncompact connected component of the common level surface of first integrals and Casimir functions is proved.

Purpose The orientation behavior of fiber is of great significance in improving the performance of fiber-reinforced polymer products. Generally, the Folgar–Tucker equation can accurately describe the variation of orientation vector of fiber, whereas the stability of numerical algorithms was the major challenge. This paper aims to propose an accurate, stable algorithm to solve the Folgar–Tucker equation for the fiber orientation behavior. Design/methodology/approach First, the mismatch problem between the strain rate and the pressure field was solved by using the integral transformation method. Then, an accurate, stable algorithm to solve the Folgar–Tucker equation based on the invariant-based optimal fitting method was proposed. The equation was discretized by finite element/finite difference method, and the Lagrange multiplier method was applied to ensure stability. Findings The proposed algorithm is proven to accurately and steadily coincide with the experimental results for different cases, including the fiber orientation behaviors under combined flow field, rectangular sheet, three-dimensional computed tomography imaging of tensile specimen and box cases. Originality/value The fiber orientation behavior during the injection molding can be accurately predicted, which plays a significant role in determining the mechanical properties of products.

We investigate the geometry of complete spacelike hypersurfaces (immersed) in a generalized Robertson-Walker spacetime $$-I\times _fM^{n}$$ . Under suitable constraints on the sectional curvature of the Riemannian fiber $$M^n$$ , on the warping function f and on the future mean curvature (that is, the mean curvature function with respect to the future-pointing Gauss map of the spacelike hypersurface), we are able to prove that such a spacelike hypersurface must be a slice $$\{t\}\times M^{n}$$ of the ambient spacetime. Nonexistence and Calabi–Bernstein type results concerning entire spacelike graphs constructed over the Riemannian fiber $$M^n$$ are also obtained, as well as applications to the Einstein–de Sitter and steady state type spacetimes are given. Our approach is based on the so-called Omori–Yau’s generalized maximum principle and on certain integrability properties due to Yau.

3-D woven textile is generated through the weaving process. Yarn is a non-continuum material domain, the structure of which is determined by inter fiber movement. In this study, the micro-geometry of 3-D orthogonal weave is generated at filament level predicting through the weaving process implementing the digital element approach (DEA). First, the basic concepts and explicit algorithm of DEA is introduced. The method of calculating adjusted digital fiber material property in terms of discretization resolution is proposed. Second, the unit-cell topology of 3-D orthogonal weave is defined by a position matrix. The calculation of potential energy of the cell is derived. At last, a dynamic weaving process is designed to investigate the effect of yarn tension on fabric micro-geometry and cell energy. 4 unit-cells are generated under 4 sets of tension combination. Results show that as the fabric thickness decrease, the filaments of the weft yarns move towards the center. The weft yarns at the top and bottom deform into their final shape first. The applied tension on weaver plays a dominant role in determining fabric thickness and convergence speed. By comparing the numerical results with the microscope pictures taken from the actual specimen, it is concluded that the fabric micro-geometry produced by tension combination 4 closely matches the experimental results.

Cosmic ray muons are widely used to study the internal structure of different large-scale natural and artificial objects. The technique is called muonography in analogy with radiography. In this work, results are presented from tests of different elements of the detecting system of the muon hodoscope under development at MEPhI.

Jute fiber has a great role in Indian economy. Since, jute fiber quality varies one place to another owing to various reasons, it becomes imperative to go for classification and gradation of jute f...

We show that certain homological regularity properties of graded connected algebras, such as being AS-Gorenstein or AS-Cohen–Macaulay, can be tested by passing to associated graded rings. In the spirit of noncommutative algebraic geometry, this can be seen as an analogue of the classical result that, in a flat family of varieties over the affine line, regularity properties of the exceptional fiber extend to all fibers. We then show that quantized coordinate rings of flag varieties and Schubert varieties can be filtered so that the associated graded rings are twisted semigroup rings in the sense of [RZ12]. This is a noncommutative version of the result due to Caldero [C02] stating that flag and Schubert varieties degenerate into toric varieties, and implies that quantized coordinate rings of flag and Schubert varieties are AS-Cohen–Macaulay. Fil: Rigal, L.. Universite de Paris 13-Nord; Francia Fil: Zadunaisky Bustillos, Pablo Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santaló". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santaló"; Argentina

In this article, we describe the underlying reduced scheme of a quaternionic unitary Rapoport–Zink space with Iwahori level structure. In a previous work, we have studied the quaternionic unitary Rapoport–Zink space with a special maximal parahoric level structure. We will describe the morphism between these two Rapoport–Zink spaces and the fibers of this morphism. As an application of this result, we describe the quaternionic unitary Rapoport–Zink space with any parahoric level structure.

We present a demonstration of software defined networking (SDN) services utilizing quantum key distribution (QKD) technology, fully integrated with standard telecommunication network connecting production facilities of Telefonica in Madrid. All communications “co-propagate” over the same fiber infrastructure.

This paper aimed to study the effect of electromagnetic field on general model of the equations of the generalized thermoelasticity reinforcement of the deformation of a micropolar generalized thermoelastic medium. The phenomenon is in the context of the couple theory (C-D), Lord-Shulman (L-S) and Green-Lindsay (G-L) as well as the Dual-Phase-Lag (DPL) models. The normal mode technique is used to find the exact expressions components of displacement, force stress, and temperature. The modifications of the considered variables with the horizontal distance are illustrated graphically to show the distance values that reduce to the variables interrupt. Comparisons are made with the results in the absence and presence of electromagnetic field for the general of reinforcement on the total deformation of a micropolar thermoelastic medium. The results obtained are calculated numerically and displayed by the graphs to show the effect of the entered new parameters on the phenomena.

For a family of varieties, we prove that the alternating sum of the traces of “local” monodromy acting on the $$\ell $$ -adic etale cohomology groups of the generic fiber is an integer that is independent of $$\ell $$ . In the course of the proof, we also establish a result on fixed points.

An image compression-encryption scheme utilizing the combination of fiber specklegram-based compressive sensing (CS) and double random phase encoding (DRPE) was demonstrated. The original image is compressed and encrypted by CS and then re-encrypted by DRPE. The measurement matrices for CS are constructed from multimode fiber specklegrams resulting from modes excitation and interference, which show better performance compared with those based on Gaussian random variables. Since fiber specklegrams have strong dependence on configuration, such measurement matrix can be constructed either by one specklegram or by specklegrams from different launched wavelengths. The double-encrypted image demonstrated good safety and reliability in several common attacks and presented high key sensitivity, which indicates good performance of the proposed scheme.

For a map $$f:X\rightarrow Y$$ f : X → Y , there is the relative model $$M(Y)=(\Lambda V,d)\rightarrow (\Lambda V\otimes \Lambda W,D)\simeq M(X)$$ M ( Y ) = ( Λ V , d ) → ( Λ V ⊗ Λ W , D ) ≃ M ( X ) by Sullivan model theory (Félix et al., Rational homotopy theory, graduate texts in mathematics, Springer, Berlin, 2007). Let $$\mathrm{Baut}_1X$$ Baut 1 X be the Dold–Lashof classifying space of orientable fibrations with fiber X (Dold and Lashof, Ill J Math 3:285–305, 1959]). Its DGL (differential graded Lie algebra)-model is given by the derivations $$\mathrm{Der}M(X)$$ Der M ( X ) of the Sullivan minimal model M(X) of X. Then we consider the condition that the restriction $$b_f:\mathrm{Der} (\Lambda V\otimes \Lambda W,D)\rightarrow \mathrm{Der}(\Lambda V,d) $$ b f : Der ( Λ V ⊗ Λ W , D ) → Der ( Λ V , d ) is a DGL-map and the related topics.

The trinions $T_N$ are a class of 5d $\mathcal{N}=1$ superconformal field theories (SCFTs) realized as M-theory on $\mathbb{C}^3/\mathbb{Z}_N \times \mathbb{Z}_N$. We apply to $T_N$, as well as closely-related SCFTs that are obtained by mass deformations, a multitude of recently developed approaches to studying 5d SCFTs and their IR gauge theory descriptions. Thereby we provide a complete picture of the theories both on the Coulomb branch and Higgs branch, from various geometric points of view - toric and gluing of compact surfaces as well as combined fiber diagrams - to magnetic quivers and Hasse diagrams., Comment: 60 pages, v2: JHEP version

Practical quantum networking architectures are crucial for scaling the connection of quantum resources. Yet quantum network testbeds have thus far underutilized the full capabilities of modern lightwave communications, such as flexible-grid bandwidth allocation. In this work, we implement flex-grid entanglement distribution in a deployed network for the first time, connecting nodes in three distinct campus buildings time-synchronized via the Global Positioning System (GPS). We quantify the quality of the distributed polarization entanglement via log-negativity, which offers a generic metric of link performance in entangled bits per second. After demonstrating successful entanglement distribution for two allocations of our eight dynamically reconfigurable channels, we demonstrate remote state preparation -- the first realization on deployed fiber -- showcasing one possible quantum protocol enabled by the distributed entanglement network. Our results realize an advanced paradigm for managing entanglement resources in quantum networks of ever-increasing complexity and service demands.

For C r ( r > 1 ) random dynamical systems F on a compact smooth Riemannian manifold M, the fiber topological entropy is bounded above by an integral formula. Particularly, for the C ∞ random dynamical systems, the integral formula coincides with the fiber topological entropy.

In this paper, we will explain a conceptual reformulation and inductive formula of the Siegel series. Using this, we will explain that both sides of the local intersection multiplicities of [GK93] and the Siegel series have the same inherent structures, beyond matching values. As an application, we will prove a new identity between the intersection number of two modular correspondences over Fp and the sum of the Fourier coefficients of the Siegel-Eisenstein series for Sp_4 of weight 2, which is independent of p (> 2). In addition, we will explain a description of the local intersection multiplicities of the special cycles over F_p on the supersingular locus of the `special fiber' of the Shimura varieties for GSpin(n; 2), n, 52 pages

In this paper, we sketch some constructions providing a link between complex-analytic geometry and nonstandard algebraic geometry via a categorical point of view. The analytic category is seen as a completed fiber of a family of nonstandard algebraic geometries by applying a standard part functor. We indicate how various notions of analytic objects fit into this context (as for example banachanalytic spaces, Kahler spaces etc.)

We construct families of principally polarized abelian varieties whose theta divisor is irreducible and contains an abelian subvariety. These families are used to construct examples when the Gauss map of the theta divisor is only generically finite and not finite. That is, the Gauss map in these cases has at least one positive-dimensional fiber. We also obtain lower-bounds on the dimension of Andreotti-Mayer loci., Comment: Final version, several typos fixed. Any comments are welcome!

This paper studies optical soliton pulses. The Kundu–Mukherjee–Naskar equation is considered because this model describes the propagation of soliton dynamics in optical fiber communication system. Bright, dark, singular, combo bright-dark solitons are emerged from the Riccati function, sine-Gordon function, F-expansion and functional variable principles.

Let [math] be a compact orientable aspherical [math] –manifold. We show that if the profinite completion of [math] is isomorphic to the profinite completion of a free-by-cyclic group or to the profinite completion of a surface-by-cyclic group, then [math] fibers over the circle with compact fiber.

The dual-beard image method, which has been developed in recent years as a fast and economical method for fiber length measurement, consists of dual-beard specimen preparation, image processing, fibrogram extraction, and length parameter calculations. However, one of the shortcomings of this method is that it can only produce extremely limited length parameters such as mean length, coefficient of variation, modal length, and quality length (UHML, upper half mean length). This study introduces a new algorithm for converting the dual-beard fibrogram into a length distribution histogram which can be used to calculate most of the current length parameters. The algorithm is based on the short fiber content formulae but modified by theoretical analysis and experimental comparison. The length distributions of 24 cotton samples and 12 wool samples are measured by dual-beard image method with the new algorithm, and Advanced Fiber Information System (AFIS) and Almeter are employed for comparison. Comparative analysis shows that the peaks and ranges of the distribution histograms using the dual-beard method are similar to those from the reference methods, and the shapes of histograms from difference methods match well with one another. In addition, five length parameters calculated from the dual-beard distributions are verified to be consistent with those measured by AFIS and Almeter. The new algorithm employed in the dual-beard image method avoids the differential operation which amplifies the curve error, giving the dual-beard image method the ability to output more comprehensive length information.

The paper presents assumptions for the fiber movement model in the drawing mechanism field, aiming at establishing a regulation equation with a modified operation algorithm of the short-term draft regulator of slivers made of staple fibers. The model takes into account the sliver retardation phenomena and makes it possible to increase the evenness of slivers feeding successive machines in the technological process. As a result of this, the evenness of yarn will be increased contributing to an improvement in the quality of flat textile fabrics. This model, despite simplifying assumptions, sufficiently precisely presents the phenomenon of reducing the effect of drawing waves on the distribution of the linear mass of the fiber stream.

The free vibration responses of the hybrid composites curved panel have been investigated in the present work. The hybrid composite is modelled numerically using the first-order shear deformation theory (FSDT). The finite element method is utilized via ANSYS and the responses are computed using a parametric design language (APDL) code. The correctness and performance of the present model has been proved and authenticated by comparing the presently calculated values with published results. Finally, the influence of shell panel geometry, constraint conditions, curvature ratio and types of hybrid on the modal behavior of the hybrid composite curved panel have been discussed in detail.

In this paper, we address the impact of multiple fiber bends on orbital angular mode (OAM) mode propagation in a fiber. In particular, we extend the OAM mode-mixing due to a single-fiber bend studied earlier in detail for the step-index fiber, to the case of a succession of bends. The bends may have relative orientation with respect to each other. Analytic expressions leading to crosstalk are given. The OAM mode intensity at the output of a pair of bends is especially studied with emphasis on the intensity pattern changes that arise from the changes in the relative orientation of the bends., Comment: 8 pages, 5 figures; to be submitted for publication in IEEE Photonics Journal

Steel fiber reinforced self-compacting concrete (SFRSCC) is a special type of concrete that is widely researched in literature due to its superior properties. As it is difficult to provide its high workability qualities, SFRSCC is thought to be in need of an economic and quick design process. In this study, it is aimed to predict the fresh properties of SFRSCC mixtures following with the standards at the preliminary design stage. With this aim, two different classification methods were applied successfully to a comprehensive dataset collected from international publications. The models used to classify the fresh performance of SFRSCC were Weighted K-Nearest Neighbors (W-KNN) and Quadratic Support Vector Machine (Q-SVM). Consequently, acceptable success rates were obtained from the models. For the prediction of slump-flow, the accuracy values were 0.76 and 0.84 for the W-KNN and Q-SVM models, respectively. For the V-funnel time, the accuracy values were 0.90 and 0.92 for the W-KNN and Q-SVM models, respectively. Owing to the recommended methods, it is expected to reduce the number of trial mixtures in the preliminary design stage of SFRSCC.

In applications of the typical distributed optical fiber sensor, DAS, it is increasingly appealing to mine deeper information to aid in accurate decision making besides basic functions of detection, positioning and identification. Thus a collaborative energy-based method of source localization is proposed to estimate the vertical offset-distance of a specific vibration source and its threat level to the buried fiber. The contributions of this article include: 1) It is for the first time to provide a feasible method to make an offset-distance estimation and then threat level prediction in the underground buried environments with DAS; 2) The spatial energy distribution characteristics of the vibration source is first discovered to have relationship with its attenuation law at different vertical offset-distances, which can be used to predict the threat level; 3) A two-stage stacking machine learning method is constructed to automatically discriminate the differences in the extracted collaborative energy distribution features of different distant vibrations. The effectiveness of this method is proved in the field test for the vibration source localization in the underground buried environments and useful discussions are included.

In this paper we present a generalization of Poincar\'e's Rotation Theory of homeomorphisms of the circle to the case of one-dimensional compact abelian groups which are solenoidal groups, {\it i.e.}, groups which fiber over the circle with fiber a Cantor abelian group. We define rotation elements, \emph{\`a la} Poincar\'e and discuss the dynamical properties of translations on these solenoidal groups. We also study the semiconjugation problem when the rotation element generates a dense subgroup of the solenoidal group. Finally, we comment on the relation between Rotation Theory and entropy for these homeomorphisms, since unlike the case of the circle, for the solenoids considered here there are homeomorphisms (not homotopic to the identity) with positive entropy.

The problem of damage in heterogeneous materials has received particular attention in recent years. The numerical models currently used in the simulation of damage require an internal length that is not currently related to a characteristic length of the material components. However, understanding damage regarding the size of the heterogeneities of the material is of crucial importance, particularly in civil engineering. The Fiber Bundle Model has been widely used to qualitatively address the issue of damage in heterogeneous media by studying the statistics of failure events during damage. The so-called ZIP model derives from Fiber Bundle Model to mimic crack propagation. In this work, a spatial correlation of tensile strength of fibers is added to the ZIP model to highlight the role of heterogeneity size in statistics of failure events during crack propagation. The addition of spatial correlation into the ZIP model modifies the distribution of failure events. Indeed, for a simulated material without spatial correlation, failure events follow two regimes. By adding a spatial correlation to the material, a transitional regime appears. The influence of spatial correlation on fiber rupture avalanche strongly depends on the ratio between the sizes of the shapes of the stress field and of the heterogeneities.

A question of Griffiths-Schmid asks when the monodromy group of an algebraic family of complex varieties is arithmetic. We resolve this in the affirmative for the class of algebraic surfaces known as Atiyah-Kodaira manifolds, which have base and fibers equal to complete algebraic curves. Our methods are topological in nature and involve an analysis of the "geometric" monodromy, valued in the mapping class group of the fiber., Comment: 44 pages, 9 figures

We consider threefold del Pezzo fibrations over a curve germ whose central fiber is nonrational. Under the additional assumption that the singularities of the total space are at worst ordinary double points, we apply a suitable base change and show that there is a one-to-one correspondence between such fibrations and certain nonsingular del Pezzo fibrations equipped with a cyclic group action.

Epigenomics is the study of modifications on the genetic material of a cell that do not depend on changes in the DNA sequence, since those latter involve specific proteins around which DNA wraps. The end result is that Epigenomic changes have a fundamental role in the proper working of each cell in Eukaryotic organisms. A particularly important part of Epigenomics concentrates on the study of chromatin, that is, a fiber composed of a DNA-protein complex and very characterizing of Eukaryotes. Understanding how chromatin is assembled and how it changes is fundamental for Biology. In more than thirty years of research in this area, Mathematics and Theoretical Computer Science have gained a prominent role, in terms of modeling and mining, regarding in particular the so-called 10 nm fiber. Starting from some very basic notions of Biology, we briefly illustrate the recent advances obtained via laboratory experiments on the organization and dynamics of chromatin. Then, we mainly concentrate our attention on the contributions given by Combinatorial and Informational Methodologies, that are at the hearth of Theoretical Computer Science, to the understanding of mechanisms determining the 10 nm fiber. We conclude highlighting several directions of investigation that are perceived as important and where Theoretical Computer Science can provide high impact results.

Usually the quality of cross sectional fiber image is affected by the slicing and imaging device, some image processing techniques could be used to solve this problem instead of hardware operation. In this paper, a series of edge detection and weighted average image fusion algorithms are used to enhance the ramie fiber image to improve the quality of fiber cross-section image obtained by the traditional section and optical microscope. The cross-section characteristic parameters of ramie fiber could be extracted after the image pre-processing including threshold segmentation, median filtering and corrosion. The experimental results show that this method can be used to solve the identification problem of low contrast ramie fiber cross-section images caused by background blur, improve the accuracy of image recognition and analysis, it provides an effective algorithm basis for the digital measurement of ramie fibers.