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Much of the research on bioinspired soft robotics has focused on capturing the interplay of biological form and function. However, existing soft robotic actuators are mostly made with linear or planar fabrication orientations that do not represent the resting geometry of complex biological systems, such as curved musculature. This work introduces the ability to create fiber-reinforced actuators with precurved configurations. By tuning variables such as dimensions and fiber angles, an optimization algorithm can prescribe the mechanical fabrication parameters to create a fiber-reinforced actuator that can generate controlled motion to follow a desired input trajectory. Precurved configurations introduce an additional optimization parameter, the initial bend angle, allowing for a more accurate and robust algorithm and generating a median percent error of1%. With a customized software tool, we can take existing motion data from biological systems-such as medical imaging-and build soft robotic actuators optimized to replicate these trajectories. We can predict the motion of precurved actuators both analytically and numerically and replicate the motion experimentally, with excellent trajectory matching between the three. In constructing actuators that better match the native forms found within biological systems, we find that precurved actuators are more efficient than their initially straight counterparts. This pneumatic efficiency allows for the use of control systems with lower power and precision, lowering the economic cost of the associated control hardware, while more accurately replicating the biological motion. Taking two examples from biology, that of the human diaphragm during respiration and that of a jellyfish bell during locomotion, we design and generate fiber reinforced actuators to mimic these motions.

This paper presents a mathematically stringent method for gap/overlap free design of carbon fiber-reinforced composites for 3D printing. The proposed method employs signed distance level set function to represent the fiber paths by extracting the equidistant iso-level set profiles, through which neighbouring fiber paths keep a constant distance, eliminating the gap and overlap defects of existing methods that generate fiber paths from discretely defined fiber angle variables. Then, a compliance minimization fiber path optimization problem is formulated under the level set framework for optimal fiber-reinforcement design. A major contribution lies in the solution of the optimization problem. The adjoint sensitivity analysis is performed to derive the gradient information for fiber path design update. More importantly, the domain integral term inside the sensitivity result is transformed into a boundary integral expression facilitated by extraction of the structural skeletons and rays. Hence, the full sensitivity result is derived instead of eliminating the non-executable domain integral terms in existing studies, which results in even faster and more stable convergence. A few numerical examples are studied to demonstrate the effectiveness of the proposed fiber path optimization method. 3D printing and mechanical testing results validate the optimized fiber-reinforcement effect, as well as the manufacturability improvement by avoiding gap and overlap defects.

An analytical approach about the general type of step-index optical fiber modes and their variations is presented in this paper. The theoretical model is solved through our analytical method. With the boundary conditions, a composite equation set is established and solved. The precise results of all modes are achieved with a high-precision numerical solution. The modal characteristic contains the distributions of electromagnetic fields, the effective refractive index, and its tendencies. The modal sensitivity is based on the former and the partial derivative of the effective refractive index (neff/ni and neff/ri). The derivative rule of implicit functions and determinant function allows our method to analyze the sensitivity of modes. Furthermore, four qualitative deductions are derived during the process, including the qualitative analysis of modes and their constraints, supporting previous experiments. Our work is beneficial for exploiting new fiber and researching relative fiber sensors.

Many biological tissues contain an underlying fibrous microstructure that is optimized to suit a physiological function. The fiber architecture dictates physical characteristics such as stiffness, diffusivity, and electrical conduction. Abnormal deviations of fiber architecture are often associated with disease. Thus, it is useful to characterize fiber network organization from image data in order to better understand pathological mechanisms. We devised a method to quantify distributions of fiber orientations based on the Fourier transform and the Qball algorithm from diffusion MRI. The Fourier transform was used to decompose images into directional components, while the Qball algorithm efficiently converted the directional data from the frequency domain to the orientation domain. The representation in the orientation domain does not require any particular functional representation, and thus the method is nonparametric. The algorithm was verified to demonstrate its reliability and used on datasets from microscopy to show its applicability. This method increases the ability to extract information of microstructural fiber organization from experimental data that will enhance our understanding of structure-function relationships and enable accurate representation of material anisotropy in biological tissues.

We give sufficient conditions for the tautness of a transversely homogenous foliation defined on a compact manifold, by computing its base-like cohomology. As an application, we prove that if the foliation is non-unimodular then either the ambient manifold, the closure of the leaves or the total space of an associated principal bundle fiber over $S^1$.

The mask is the main attribute in Malang Mask Show. The representation of Malang masks has undergone adaptation along with the development of the times, which were originally made of wood. This study aims to analyze the Malang mask material from the adaptation process of fiber raw materials as its component. The research approach method is descriptive qualitative. Data collection techniques using observation and interviews as the unit of analysis descriptively. The results of the study on the adaptation of the raw material for making Malang masks from wood into fiber as a medium of learning and the preservation of local culture as a medium of learning in schools. The technique of making Malang masks with fiber material uses the basic principles of printing and finishing techniques in the painting process using acrylic paint. An important finding from this research is that the Malang Mask making material using fiber has long durability, does not rot because it is synthetic

We develop the Gompf fiber connected sum operation for symplectic orbifolds. We use it to construct a symplectic 4-orbifold with b 1 = 0 {b_{1}=0} and containing symplectic surfaces of genus 1 and 2 that are disjoint and span the rational homology. This is used in turn to construct a K-contact Smale–Barden manifold with specified 2-homology that satisfies the known topological constraints with sharper estimates than the examples constructed previously. The manifold can be chosen spin or non-spin.

We introduce the notion of minimal reduction type of an affine Springer fiber, and use it to define a map from the set of conjugacy classes in the Weyl group to the set of nilpotent orbits. We show that this map is the same as the one defined by Lusztig in Lfromto, (2011) and that the Kazhdan–Lusztig map in Kazhdan and Lusztig, (1998) is a section of our map. This settles several conjectures in the literature. For classical groups, we prove more refined results by introducing and studying the “skeleta” of affine Springer fibers.

In infrared optical wireless communications, narrow beams require the perfect calibration of the base station (BS) and user terminal (UT), which cannot support multiple moving users. This paper proposes a fiber lens based optical antenna, which employs a fiber unit array and a transmit lens to generate multiple beams, achieving full beam coverage. Specifically, we first design a fiber lens to extend the spreading angle of the emitted lights. We employ the wave optics to analyze the characteristic of the fiber lens and use the geometric optics to design the parameters of the lens. With the fiber lens, we then design the optical antenna consisting of a hexagonal fiber unit array and a transmit lens. Each fiber unit generates a beam to a specific direction and different fiber units irradiate different directions. All the generated beams can fully cover the communication area. Thus, the BS has the potential to support multi-user communication via multiple beams. Simulation results verify the performance of the designed fiber lens and the optical antenna achieving full beam coverage.

There are fundamental truths with which we must not lose touch. We need to articulate them on occasions. So, I will be talking about fundamental things today. You need not agree with all that I say. You may argue with my definitions. You may want to substitute, or add, retract, or even object to some of my thoughts. But think about them you must. For what I will be talking about is the very fiber and substance of our field. - Robert J. Demarest

Let $X$ be a bundle over $S^1$ with fiber a 3--manifold $M$ and with monodromy $\varphi$. Gay and Kirby showed that if $\varphi$ fixes a genus $g$ Heegaard splitting of $M$ then $X$ has a genus $6g+1$ trisection. Genus $3g+1$ trisections have been found in certain special cases, such as the case where $\varphi$ is trivial, and it is known that trisections of genus lower than $3g+1$ cannot exist in general. We generalize these results to prove that there exists a trisection of genus $3g+1$ whenever $\varphi$ fixes a genus $g$ Heegaard surface of $M$. This means that $\varphi$ can be nontrivial, and can preserve or switch the two handlebodies of the Heegaard splitting. We additionally describe an algorithm to draw a diagram for such a trisection given a Heegaard diagram for $M$ and a description of $\varphi$.

Recent advances in neuroimaging technologies have provided opportunities to acquire brain images of different modalities for studying human brain organization from both functional and structural perspectives. Analysis of images derived from various modalities involves some common goals such as dimension reduction, denoising, and feature extraction. However, since these modalities have vastly different data characteristics, the current analysis is usually performed using distinct analytical tools that are only suitable for a specific imaging modality. In this paper, we present a Distributional Independent Component Analysis (DICA) that represents a new approach that performs decomposition on the distribution level, providing a unified framework for extracting features across imaging modalities with different scales and representations. When applying DICA to fMRI images, we successfully recover well-established brain functional networks in neuroscience literature, providing empirical validation that DICA delivers neurologically relevant findings. More importantly, we discover several structural network components when applying DICA to DTI images. Through fiber tracking, we find these DICA-derived structural components correspond to several major white fiber bundles. To the best of our knowledge, this is the first time these fiber bundles are successfully identified via blind source separation on single subject DTI images. We also evaluate the performance of DICA as compared with existing ICA methods through extensive simulation studies.

We explain an algorithm to calculate Arthur’s weighted orbital integral in terms of the number of rational points on the fundamental domain of the associated affine Springer fiber. The strategy is to count the number of rational points of the truncated affine Springer fibers in two ways: by the Arthur–Kottwitz reduction and by the Harder–Narasimhan reduction. A comparison of results obtained from these two approaches gives recurrence relations between the number of rational points on the fundamental domains of the affine Springer fibers and Arthur’s weighted orbital integrals. As an example, we calculate Arthur’s weighted orbital integrals for the groups ${\textrm {GL}}_{2}$ and ${\textrm {GL}}_{3}$ .

We consider Hessenberg varieties in the flag variety of $GL_n(\mathbb{C})$ with the property that the corresponding Hessenberg function defines an ad-nilpotent ideal. Each such Hessenberg variety is contained in a Springer fiber. We extend a theorem of Tymoczko to this setting, showing that these varieties have an affine paving obtained by intersecting with Schubert cells. Our method of proof constructs an an affine paving for each Springer fiber that restricts to an affine paving of the Hessenberg variety. We use the combinatorial properties of this paving to prove that Hessenberg varieties of this kind are connected., Comment: 21 pages

In this paper, the Sagnac interferometer with a one-way optical fiber ring and a novel dual Sagnac distributed fiber vibration sensor with an asymmetrical structure for disturbance localization is proposed. The two Sagnac interferometers in this system are asymmetrical and equal in the lengths of optical paths. Using time delay estimation based on cross-correlation, the disturbance localization can be calculated from the two demodulated phase signals. The localization precision is ±10 m with a 50 km sensing fiber and the overall localization error is 0.02%. The time error problem possibly existing in the fiber sensing systems based on time delay estimation is firstly studied. Due to the design of equal optical path lengths, the time error problem does not exist in this system, which is a possible reason for high localization precision. The system has application potential in long-distance perimeter security and many other fields.

To each variety $X$ and a nonnegative integer $m$, there is a space $X_m$ over $X$, called the jet scheme of $X$ of order $m$, parametrizing $m$-th jets on $X$. Its fiber over a singular point of $X$ is called a singular fiber. For a surface with a rational double point, Mourtada gave a one-to-one correspondence between the irreducible components of the singular fiber of $X_m$ and the exceptional curves of the minimal resolution of $X$ for $m \gg 0$. In this paper, for a surface $X$ over complex number with a singularity of $A_n$ or $D_4$-type, we study the intersections of irreducible components of the singular fiber and construct a graph using this information. The vertices of the graph correspond to irreducible components of the singular fiber and two vertices are connected when the intersection of the corresponding components is maximal for the inclusion relation. In the case of $A_n$ or $D_4$-type singularity, we show that this graph is isomorphic to the resolution graph for $m \gg 0$., 18 pages

Studies of sensory-evoked neuronal responses often focus on mean spike rates, with fluctuations treated as internally-generated noise. However, fluctuations of spontaneous activity, often organized as traveling waves, shape stimulus-evoked responses and perceptual sensitivity. The mechanisms underlying these waves are unknown. Further, it is unclear whether waves are consistent with the low rate and weakly correlated “asynchronous-irregular” dynamics observed in cortical recordings. Here, we describe a large-scale computational model with topographically-organized connectivity and conduction delays relevant to biological scales. We find that spontaneous traveling waves are a general property of these networks. The traveling waves that occur in the model are sparse, with only a small fraction of neurons participating in any individual wave. Consequently, they do not induce measurable spike correlations and remain consistent with locally asynchronous irregular states. Further, by modulating local network state, they can shape responses to incoming inputs as observed in vivo., Spontaneous traveling cortical waves shape neural responses. Using a large-scale computational model, the authors show that transmission delays shape locally asynchronous spiking dynamics into traveling waves without inducing correlations and boost responses to external input, as observed in vivo.

A service optimization method for polyester fiber production process is proposed. According to the production batch and production specifications, the method considers the service cost as the optimization objective, and uses data model to determine the specific process parameters in the polyester fiber production process. First, two options for the overall process of polyester fiber are introduced: on-demand manufacturing and product development. Second, the impact of different batch request tasks on the performance index of each stage is determined. Finally, the service optimization measures of different batches are proposed. By comparing the similarity between the current data samples and the overall data, the optimal production plan of the overall production process is formed. Simulation results show that the immune algorithm inspired from endocrine regulation has the best performance on the optimal decision-making combination, which is helpful for the development of new polyester products. We investigate how to reduce energy consumption of system resources, and how to choose the best service from a large number of candidate services. In the overall polyester fiber production process, users are not only consumers, but also designers and producers, achieving the real “integration of production and consumption”.

In this paper, a new consistent analytical model is proposed for second-order direct analysis of steel structures with tapered members allowing for both symmetric and asymmetric variations. The proposed model is implemented in a flexibility-based beam-column element with considering initial geometrical imperfections at the element level. To account for the influence of varied tapering ratios on the member behavior, a new initial geometrical imperfection pattern is introduced for both prismatic and non-prismatic members using common section shapes such as I-shape, Tee-shape, circular and rectangular hollow sections. Note that the conventional bow imperfection pattern that is widely accepted for prismatic members may lead to unsafe design when it is adopted for the tapered members. Furthermore, residual stress is explicitly considered through a fiber section approach in the proposed beam-column element. Consequently, the traditional effective length method is no longer required, as both geometrical imperfections and residual stress have been taken into account. The progressive yielding behavior of tapered members is also considered through the fiber section with nonlinear stress–strain relationships. Thus, a comprehensive second-order direct analysis method is proposed for safer and more economical design of tapered structures without the assumption of the effective length factor for a stability check. Several numerical examples are employed to verify the accuracy and practicability of the proposed model.

An accurate power map is mandatory to evaluate the performance of optical fiber transmissions in the nonlinear transmission region. In this letter, we discuss the performance variation in dispersion unmanaged fiber links due to power excursions, overarching the fiber nonlinearity that imposes a fundamental limit on the capacity of optical fiber transmissions. After using digital back-propagation (DBP) in optical fiber transmissions, the performance degradation due to power excursions shows different characteristics, depending on the location of the power excursion. Further, due to the cascading effect of the nonlinear signal-noise interaction (NSNI), the power excursion on the latter spans exerts a greater impact than that on the front spans. We implement a polarization-multiplexed 16-QAM over 12 spans of standard single-mode fiber (SSMF) experiment. The experimental results verify our theoretical analyses that the received SNRs after DBP can be sensitive to the power excursion and its location.

Equivalent-graded-index photonic-crystal fiber (EGI-PCF) is a modified photonic-crystal fiber (PCF) where the cladding is not required to be periodic. A radial gradient of the equivalent refractive index distribution provides extra freedom to efficiently tailor the dispersion of EGI-PCF. However, such additional complexity makes the manual fiber design much more challenging where the time consumption becomes too much to be afforded eventually. In this paper, we for the first time propose the method of computer-aided inverse fiber design (CAFD) based on empirical dispersion formula to circumvent this hurdle. We apply the differential evolution (DE) genetic algorithm to seek for the optimized EGI-PCF design with a target of specific dispersion profile. In the dispersion oriented EGI-PCF design, the use of empirical formula instead of numerical simulation (e.g., finite-element method) is proved to greatly reduce the run-time of CAFD and simplifies the fitness function evaluation as much as possible. We adopt our method and demonstrate a design of EGI-PCF with a near-zero ultra-flattened dispersion in the whole S+C+L band, which merely costs a few seconds of a laptop to return an optimized fiber design. Thus improvement of efficiency is about three orders of magnitude faster than any previous CAFD attempts as far as we learn. In the end, we use our method to explore an EGI-PCF design with a unique dispersion profile of all-normal dispersion-decreasing along the fiber length centered around 1 μm that plays a key role for the self-similar pulse evolution in a fiber laser/amplifier.

Anisotropic fiber-reinforced composites are used in lightweight construction, which is of great industrial relevance. During mold filling of fiber suspensions, the microstructural evolution of the local fiber arrangement and orientation distribution is determined by the local velocity gradient. Based on the Folgar–Tucker equation, which describes the evolution of the second-order fiber orientation tensor in terms of the velocity gradient, the present study addresses selected states of deformation rates that can locally occur in complex flow fields. For such homogeneous flows, exact solutions for the asymptotic fiber orientation states are derived and discussed based on the quadratic closure. In contrast to the existing literature, the derived exact solutions take into account the fiber-fiber interaction. The analysis of the asymptotic solutions relying upon the common quadratic closure shows disadvantages with respect to the predicted material symmetry, namely, the anisotropy is overestimated for strong fiber-fiber interaction. This motivates us to suggest a novel normalized fully symmetric quadratic closure. Two versions of this new closure are derived regarding the prediction of anisotropic properties and the fiber orientation evolution. The fiber orientation states determined with the new closure approach show an improved prediction of anisotropy in both effective viscous and elastic composite behaviors. In addition, the symmetrized quadratic closure has a simple structure that reduces the effort in numerical implementation compared to more elaborated closure schemes.

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

Purpose Seepage of the dam is an important safety problem, which may cause internal erosion of the structure. In the field of seepage monitoring in civil engineering, the distributed optical fiber sensing technology based on the temperature tracing method has been paid more attention due to its unique advantages of high sensitivity, good stability and high resolution. The purpose of this paper is to make a review of the existing related research, so as to facilitate the later scholars to understand and further study more systematically. Design/methodology/approach In this paper, three kinds of commonly used distributed fiber temperature measurement technologies are introduced. Based on the working principle, monitoring system, theoretical analysis, experimental research and engineering application of the fiber seepage monitoring technology, the present situation of dam seepage monitoring based on distributed fiber is reviewed in detail and their advantages and disadvantages are compared. Findings The thermal monitoring technology of seepage measurement depends on the accuracy of optical fiber temperature measurement (including the accuracy of the system and the rationality of the discrimination method), the correct installation of optical fiber and the quantitative analysis of temperature data. The accuracy of the current monitoring system can basically meet the existing measurement requirements, but the correct installation of optical fiber and the calibration of temperature data need to be further studied for different discrimination methods, and this field has great research value. Originality/value At present, there are many applications and research studies of optical fiber sensing in the field of structural health monitoring, and there are also reviews of related aspects. However, there is little or no review only in the field of seepage monitoring. This paper summarizes the research and application of optical fiber sensing in the field of seepage monitoring. The possibility of the gradient method to find its new prospect with the development of monitoring systems and the improvement of temperature resolution is discussed. The idea of extending the seepage monitoring method based on distributed optical fiber thermal monitoring technology to other monitoring fields is also given in the paper.

Cotton is the main source of renewable fiber in the world and is primarily used for textile production. This study analyzed 3,856 papers of cotton research from Plant Sciences category during 1990 ...

We describe a scheme for generation of spatial-mode-entangled photon pairs in a few-mode fiber and experimentally demonstrate generation of idler beams from classical seed signals representing various superpositions of fiber LP01 and LP $_{11a}$ modes. For every signal mode superposition, we observe the indication of idler mode orthogonality to the signal mode.

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.

This paper attempts to display, analyze and discuss the literature affiliated to the previous research data on road surfacing in pavement engineering reinforcement. In this paper, a review of the background and present status of road surfacing is also provided for supportive explanation of the significance of fiber-reinforced asphalt pavement HMA and its role in providing effective and durable surfacing for heavy-trafficked roads. The paper attempts to clarify some of the terms and notions related to the discussions to give the readers the needed background, to be able to actively understand the experiments and discussions. Results from many studies confirm that fiber specifically enhances the optimum bitumen content in the design of the mixture and halts the bitumen leakage due to its asphalt absorbing susceptibility. Fiber modifies the visco-elastic response, susceptibility against moisture, increase resistance to rutting, as well as lowers the pavement fatigue cracking.

In this letter, we propose a novel 3D shape sensing algorithm for flexible endoscopic surgery using multi-core fiber Bragg grating (FBG) sensors. Considering the signal noises and environmental perturbations, the direct use of FBG measurements for shape sensing and position estimation is regarded as far from accurate and stable, especially when utilized in the sensing of long and flexible surgical instruments. To solve this problem, a novel and generic model-based filtering technique for the iterative curvature/twist estimation by taking advantage of the configurations of the multi-core FBGs in the optical fiber is introduced to remedy the sensory noises. Besides, we introduce an enhanced moving average approach to smooth the estimated curvatures and twists spatially on the fiber. We extensively validate our algorithm by conducting shape sensing tasks in simulations under varying conditions, and in experiments using a robotic-assisted colonoscope system integrated with a multi-core FBG fiber. The results prove our method substantially outperforms the conventional approach in the aspect of estimation accuracy and robustness, showing the superiority and application feasibility.

To assess normal organization of frontostriatal brain wiring, we analyzed diffusion magnetic resonance imaging (dMRI) scans in 100 young adult healthy subjects (HSs). We identified fiber clusters intersecting the frontal cortex and caudate, a core component of associative striatum, and quantified their degree of deviation from a strictly topographic pattern. Using whole brain dMRI tractography and an automated tract parcellation clustering method, we extracted 17 white matter fiber clusters per hemisphere connecting the frontal cortex and caudate. In a novel approach to quantify the geometric relationship among clusters, we measured intercluster endpoint distances between corresponding cluster pairs in the frontal cortex and caudate. We show first, the overall frontal cortex wiring pattern of the caudate deviates from a strictly topographic organization due to significantly greater convergence in regionally specific clusters; second, these significantly convergent clusters originate in subregions of ventrolateral, dorsolateral, and orbitofrontal prefrontal cortex (PFC); and, third, a similar organization in both hemispheres. Using a novel tractography method, we find PFC-caudate brain wiring in HSs deviates from a strictly topographic organization due to a regionally specific pattern of cluster convergence. We conjecture cortical subregions projecting to the caudate with greater convergence subserve functions that benefit from greater circuit integration.

The thesis of this paper is that gratitude is “hard-wired” into the very fiber of our being. Humans were created in the image and likeness of God, and God was thankful for what God had created. Thus, if we are the imago Dei, we must feel gratitude as God did. The author suggests that one of the key components of the imago Dei is the Erotic, explaining that the Erotic is more than what we do sexually; on the contrary, it adds texture and fiber to every area of our lives, resulting in passion, com/passion, and mutuality. It inspires us to reach beyond ourselves to others, as Jesus directed his disciples to do when he said, “Love your neighbor as yourself,” and as he demonstrated with his inclusive, healing touch. Using feminist and queer theology and biblical interpretation, Bohache demonstrates that the Other is our neighbor and that our gratitude must extend to those who are unlike ourselves. Often, marginalized or oppressed people have the ability to express gratitude in extraordinary ways, simply by virtue of what they have experienced as the Other. The author describes some paradigms that have been proposed for accessing gratitude and thus tapping into our imago Dei, concluding with how we might still empower gratitude, com/passion, and mutuality in the midst of a pandemic.

Identification of cashmere and wool fibers has always been one of the essential topics in the field of textile. To solve this problem, this paper proposes anew overlapped fiber recognition method b...

We describe the topology of the local Milnor fiber of a function f defined on a 3-dimensional subanalytic subset $$W \subset {\mathbb {R}}^3$$ , in terms of the embedded topological type of its link $$K_f$$ . Precisely, we prove that the interior of the local Milnor fiber of $$\Vert f\Vert $$ is homeomorphic to the complement of $$K_f$$ in the corresponding sphere, extending a result due to Milnor to non-analytic situations. We also prove that the topology of the fiber does not change if we use a suitable fundamental system of neighborhoods instead of balls, extending to the real setting a classical result due to Le and Teissier for complex functions.

The cerebral atlas of diffusion tensor magnetic resonance image (DT-MRI, shorted as DTI) is one of the key issues in neuroimaging research. It is crucial for comparisons of neuronal structural integrity and connectivity across populations. Usually, the atlas is constructed by iteratively averaging the registered individual image. In tradition, the fuzzy group average image is easily generated in the initial stage, which is harmful to providing clear guidance for subsequent registration, to the performance of the final atlas. To solve this problem, an improved unbiased DTI atlas construction algorithm based on adaptive weights is proposed in this paper. The adaptive weighted strategy based on diffeomorphic deformable tensor registration is introduced. At the same time, the distance measure for tensors is used as a constraint condition, which ensures the unbiasedness of the atlas. Then, using 77 DTIs from the dataset in http://www.brain-development.org , three study-specific atlases, i.e. the constructed atlases of the proposed algorithm and two open-sourced algorithms (DTIAtlasBuilder and DTI-TK), are compared with two standardized atlases (IIT v. 4.1 and NTU-DSI-122-DTI). The performances of the atlases were evaluated in spatial normalization way with six region-based criteria (including Euclidean distances between diffusion tensors, Euclidean distances of the deviatoric tensors, standard deviation, overlaps of eigenvalue-eigenvector, cross-correlations and three sets angles of eigenvalue-eigenvector pairs between diffusion tensors) and three fiber-based criteria (including distances between fiber bundles, angles between fiber bundles and fiber property profile-based criteria). The experimental results showed that the overall performances of the study-specific atlases are better than those of the standardized atlases for specific datasets, and the comprehensive performance of the improved algorithm proposed in this paper is the best.

This article investigates whether the white matter (WM) anatomical changes exist in the brain of professional chess players. Diffusion magnetic resonance imaging (dMRI) and fiber tracking provide a unique, noninvasive technique to study brain WM microstructures in vivo . However, existing methods focused on the entire tracts without detailed anatomical annotation, which depended on expert neuroanatomical knowledge to subdivide and annotate fiber tracts. This article used an automatically annotated fiber clustering method to identify anatomically meaningful WM structures from the whole brain’s tractography. Each fiber was resampled to 200 equally spaced nodes along the whole tract to detect local differences. We calculated diffusion characteristics for 4 regions and 64 fiber clusters of professional chess players ( $n = 28$ ) and matched controls ( $n = 29$ ). The experimental results showed that there were significant differences in the diffusion characteristics of continuous locations in the thalamofrontal tracts and left superior longitudinal fasciculus. Pearson correlation analysis was also performed to prove our results. Professional chess players are significantly correlated with training duration and training frequency. Their brain structures have changed due to cognitive aspects, such as learning and memory. It is very meaningful to study the cognitive mechanism of change, which can improve high-level cognitive ability.

In this paper, warped product mixed generalized quasi-Einstein manifolds MG(QE) $$_{n}$$ are studied. It is shown that a Ricci recurrent MG(QE) $$_{n}$$ manifold is a product manifold whose factors are Ricci recurrent. Sufficient conditions for a MG(QE) $$_{n}$$ to be a G(QE) $$_{n}$$ are derived. Then, we classify three types of warped product MG(QE) $$_{n}$$ . For example, it is proved that the fiber manifold is Einstein in the first type, (QE) $$_{n}$$ in the second type and MG(QE) $$_{n}$$ in the third type.

This paper presents a novel modeling and compensation method for the volumetric errors of a six-axis gantry automated fiber placement (AFP) machine. Based on the screw theory, the forward and inverse kinematics models of the AFP machine are established. In order to improve the accuracy of the inverse kinematics solution, the Paden-Kahan sub-problem method is used to perform the inverse kinematics solution for the simplified topology of the rotary axes. Using error motion twist to establish a volumetric error transfer model for 54 geometric errors. According to the measurement data of a laser tracker and the Levenberg-Marquardt method to identify the geometric error parameters. The explicit formula of the inverse kinematics solution is used to obtain the error compensation of each motion axis, and the G code of the laying path is modified by the iterative method to realize the compensation of the volumetric errors. By comparing the positions of the tool center point before and after the error compensation, the practicability of the volumetric error modeling and iterative compensation methods are verified, and the geometric accuracy of the AFP machine can be effectively improved.

Instead of inscribing the discrete phases into each local period of the seed HLPG, an equivalent approach to realize the phase-only sampled multichannel helical long-period fiber grating (HLPG) has been demonstrated both theoretically and experimentally which is realized by superposing the so-called sampling HLPGs with the seed HLPG in a same region of the fiber. The proposed approach can greatly facilitate the fabrication processes of the multichannel HLPG by using the direct CO2 laser writing technique, meanwhile it enables to provide much more design and fabrication flexibilities for high channel-count HLPG than the previous methods. As examples, a 3-channel and a 5-channel HLPG have been successfully demonstrated. Moreover, the orbital angular momentum (OAM) modes inherently existed at all channels of the fabricated HLPG have also been verified, which highlights that the proposed HLPGs could find application to multi-wavelength OAM mode converter as well.

Somatotopy is an important guiding principle for sensory fiber organization in the primary somatosensory cortex (S1), which reflects tactile information processing and is associated with disease-related reorganization. However, it is difficult to measure the neuronal encoding scheme in S1 in vivo in normal participants. Here, we investigated the somatotopic map of the undominant hand using a Bayesian population receptive field (pRF) model. The model was established in hand space with between- and within-digit dimensions. In the between-digit dimension, orderly representation was found, which had low variability across participants. The pRF shape tended to be elliptical for digits with high spatial acuity, for which the long axis was along the within-digit dimension. In addition, the pRF width showed different change trends in the 2 dimensions across digits. These results provide new insights into the neural mechanisms in S1, allowing for in-depth investigation of somatosensory information processing and disease-related reorganization.

Diffusion tensor imaging (DTI) consistently detects increased mean diffusivity and decreased fractional anisotropy with advancing age in regions of primarily single white matter (WM) fiber populations, but findings have been inconsistent in regions of more complex fiber architecture. Given that DTI remains more common for characterizing aging WM than advanced diffusion MRI models due to DTI's simplicity, robustness, and efficiency, it is critical to strive to maximize the information extracted from DTI across the entire WM. The present study uses an orthogonal diffusion tensor decomposition based on the 3 eigenvalue moments (mean diffusivity, norm of anisotropy, and mode of anisotropy), yielding clear voxelwise degeneration patterns across the WM, including regions of complex fiber architecture. This indicates that the previous challenges of DTI in these regions were due to the choice of tensor decomposition rather than the DTI model itself. This study therefore presents a revised view of DTI of aging WM and indicates how age-related degeneration in complex fiber architecture can manifest in forms other than decreased fractional anisotropy.

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 .

The directional deviation and wrinkling deformation of the fibers need to be strictly controlled within a specific range to guarantee the final formed composite component's quality. This work proposed a novel method for generating an initial path that is proportionally adjustable between the fixed-angle and the geodesic direction to satisfy the fiber directional deviation and wrinkling deformation constraints. The paths under multiple reference lines are better suited to component geometry than paths under a single reference line. In the path offset process, a parallel equidistant offset algorithm considering the design and manufacturing constraints was proposed, which avoids the generation of unqualified paths. Simulation results showed that the proposed path generation methods have better design flexibility and higher path planning efficiency.

The case is about Reliance Jio Infocomm Limited (Reliance Jio), a subsidiary of Reliance Industries in India, it discusses the positioning of Reliance Jio in the context of Indian Internet Space. T...

Quantum key distribution (QKD) protocols based on high-dimensional quantum states have shown the route to increase the key rate generation while benefiting of enhanced error tolerance, thus overcoming the limitations of two-dimensional QKD protocols. Nonetheless, the reliable transmission through fiber links of high-dimensional quantum states remains an open challenge that must be addressed to boost their application. Here, we demonstrate the reliable transmission over a 2-km-long multicore fiber of path-encoded high-dimensional quantum states. Leveraging on a phase-locked loop system, a stable interferometric detection is guaranteed, allowing for low error rates and the generation of 6.3 Mbit/s of a secret key rate.

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