The color-matching model is conducive to expanding the scope of application of colorful fabrics and can speed up the achievement of intelligent production. To solve the problem in which the existing color-matching system of intelligent colored spun yarn cannot be applied to the digital rotor-spinning products of dope dyed viscose fiber, 66 types of mélange yarn were spun with a digital rotor-spinning frame using red, yellow, and blue dope dyed viscose fibers at a ratio gradient of 10%. Furthermore, the knitted fabric samples were produced using a circular machine. Meanwhile, a Datacolor 650 spectrophotometer was used for color testing, and the experimental results were recorded. Based on the color-matching model of the Kubelka–Munk theory, a color-matching model is built based on the experimental results. In addition, the accuracy of the model was analyzed and verified using the least-squares and relative value methods. The results show that, compared with the relative value method, the color-matching model constructed using the absorption coefficient K value and scattering coefficient S value calculated based on the least-squares approach is more accurate. The error between the predicted ratio of the test sample and the actual ratio was only 0.0979, the average color difference was only 0.465, and there were no visible differences between the predicted color of the sample and the actual color.

The task of the fiber transport channel (FTC) is to transport the fibers from the carding roller to the rotor. Its geometric position in the spinning machine has a strong influence on the characteristics of the airflow field and the trajectory of the fiber motion in both the rotor and the FTC. In this paper, a three-dimensional pumping rotor spinning channel model was established using ANSYS-ICEM-CFD software with three different positions of the FTC (positions a–c). Further, the simulations of air distribution were performed using Fluent software. In addition, the discrete phase model was used to fit the fiber motion trajectory in the rotor. The simulation results showed that among the three types of FTC, position b is the optimal condition. The gradients of airflow velocity in the channel at position b were greater than those of the other two positions, which is conducive to straightening of the fiber.

Coaxial-electrospinning is a new method used in tissue engineering and drug delivery field. It can spin nanofibers with shell-core structure through electrospinning of two polymer solutions. In this study, collagen was used as the outer layer or the shell and thermoplastic polyurethane (TPU) was used as the inner layers or the core. A series of tests were conducted to characterize the compound nanofiber and its membrane. Morphology and microscopy of the ultrafine fibers were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), whereas the fiber diameter distribution was understood using image visualization software (ImageJ) and measurements of solution viscosity and conductivity. Mechanical measurements were carried out by applying tensile test loads to samples which were prepared from electrospun ultra fine non-woven fiber mats. The results demonstrated that these composite nanofibers had the characters of native extracellular matrix and they could be designed as the scaffold for tissue engineering and functional biomaterials.

In this study, regenerated silk fibroin (RSF, from Bombyx mori) nanofibers with smooth surface had been successfully prepared via electrospinning, as shown by SEM and then as-spun fibers were induced under 75% ethanol vapor. We aimed to investigate the morphology and structure change of 75% ethanol vapor-induced silk fibroin nanofibers. To determine any difference in surface topographies, the nanofibers were inspected using atomic force microscope (AFM) and the results showed that after inducement of 75% ethanol vapor for 24 h, the surface of fibers became rough. Differential Scanning Calorimetry (DSC) analysis indicated that electrospun SF nanofibrous membranes typically took silk I form and 75% ethanol vapor-induced SF nanofibrous membranes took silk II structure. These results suggested that 75% ethanol vapor inducement could be an attractive alternative to expand the application of RSF.

Abstract-In many applications, there are strong discrepancies between the signal models assumed in the design phase and the actual signals encountered in the field. These discrepancies penalize significantly the performance of the matched filter that is fine tuned to the preassumed conditions.We propose a geometric framework that designs, via wavelet multiresolution-based techniques, a receiver whose performance is to a large degree insensitive to these mismatches. We say that the receiver is a focused detector. The approach defines a signal set S that identifies the class of diverse conditions that are expected to arise. We illustrate the method in the context of multipath problems. The matched filter, which is a simple receiver, assumes that S is a singleton. When this is not the case, the matched filter experiences strong degradation. On the other hand, the optimal receiver for the signal set S is practically infeasible since it requires a multidimensional nonlinear optimization.The paper designs the focused receiver as a good compromise between these two extremes. We replace the signal set S by a linear subspace G-the representation subspace-that minimizes a measure of similarity with S. We choose G to be a multiresolution subspace. This choice resolves to satisfaction several issues: The subspace design is reduced to the design of a single shiftable scaling function, the similarity between S and G can be computed explicitly, and the focused receiver that computes the energy of the orthogonal projection on G is implemented by a bank of correlators matched to scaled/delayed versions of the reshaped scaling function followed by an energy detector. We assume that the transmitted signal is a sample of a random process. The signal set S becomes an ensemble of linear spaces.We introduce the modified deflection as the appropriate similarity measure. The paper details our algorithm, describes how to compute the modified deflection, and illustrates the performance results that can be obtained.