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Laser additive manufacturing has attracted considerable interest as a promising digital manufacturing technology in recent years. However, poor surface quality restricts its practical application. In this paper, we demonstrate the capability of laser polishing in rough surface of additive manufactured Inconel 718 alloy. Both as-received surface and laser-polished surface were analyzed carefully by Confocal Microscope, Scanning Electron Microscopy, Energy Dispersive Spectrometer and X-ray Diffraction. The results revealed that as-received Inconel 718 alloy with surface roughness more than 7 µm could be reduced to less than 0.1 µm through laser polishing (LP) process. Moreover, microstructure, micro-hardness and wear resistance of laser-polished zone were investigated. This preliminary study has shown the potential of laser polishing in improving surface finish and properties of additive manufactured superalloy without damage to the substrate.

Ultrasound image diagnosis of breast tumors has been widely used in recent years. However, there are some problems of it, for instance, poor quality, intense noise and uneven echo distribution, which has created a huge obstacle to diagnosis. To overcome these problems, we propose a novel method, a breast cancer classification with ultrasound images based on SLIC (BCCUI). We first utilize the Region of Interest (ROI) extraction based on Simple Linear Iterative Clustering (SLIC) algorithm and region growing algorithm to extract the ROI at the super-pixel level. Next, the features of ROI are extracted. Furthermore, the Support Vector Machine (SVM) classifier is applied. The calculation states that the accuracy of this segment algorithm is up to 88.00% and the sensitivity of the algorithm is up to 92.05%, which proves that the classifier presents in this paper has certain research meaning and applied worthiness., Comment: This is a pre-print of a contribution published in Frontier Computing - Theory, Technologies and Applications (FC 2019) published by Springer

3D reconstruction is a fundamental issue in many applications and the feature point matching problem is a key step while reconstructing target objects. Conventional algorithms can only find a small number of feature points from two images which is quite insufficient for reconstruction. To overcome this problem, we propose SeFM a sequential feature point matching algorithm. We first utilize the epipolar geometry to find the epipole of each image. Rotating along the epipole, we generate a set of the epipolar lines and reserve those intersecting with the input image. Next, a rough matching phase, followed by a dense matching phase, is applied to find the matching dot-pairs using dynamic programming. Furthermore, we also remove wrong matching dot-pairs by calculating the validity. Experimental results illustrate that SeFM can achieve around 1,000 to 10,000 times matching dot-pairs, depending on individual image, compared to conventional algorithms and the object reconstruction with only two images is semantically visible. Moreover, it outperforms conventional algorithms, such as SIFT and SURF, regarding precision and recall., Comment: This is a pre-print of a contribution published in Frontier Computing - Theory, Technologies and Applications (FC 2019) published by Springer

This study carried out the direct-bonding between titanium and polyamide using nanosecond laser, investigated the effect of the textured micro-groove depth on the strength of the joint and obtained the optimal joint strength.

Variable bit rate (VBR) video will be the predominant application in the future’s multimedia communication networks. Understanding the characteristics of VBR video is important for us to utilize network resources effectively. A brief description of MPEG-1 video sources is given. The essentials of self-similarity and long-range dependence are also presented. Furthermore, some methods of estimating Hurst parameter are described in details. We analyze an hour-long MPEG-1 video trace, and the details of statistical results are discussed. The results highlight that the trace generated by MPEG-1 code has both the short-range dependence and long-range dependence structures.

A kind of single-input single-output neural net adaptive controller (SISO-NNC) and its algorithm have been presented. For the computer simulation and the special requirements of control problem, we have improved traditional BP algorithm and solved the problem of local minimum to some extent. Using the SISO-NNC to control time-varying system, the simulation results show advantages of neural net controller in control field.

An equivalent noise model of optical receiver amplifiers as shown in Fig. 1 has been given in many fiber optical communication literatures. It is proved in this paper that this equivalent noise model is neither equivalent to the original one nor measurable. The main reason is that the position of the input impedance in this noise model is not the same with its in the typical noise model, but the sameS vn,S in with the typical noise model are used. So the equivalent noise model above is wrong and is not fit to be taken into application.

We report electronic Raman scattering measurements on Ba(Fe1?xCox)2As2 (x = 0.065 and 0.2) single crystals with Raman shifts from 9 cm?1 up to 600 cm?1 in the symmetry of B1g with respect to 1 Fe unit cell. When the crystals are cooled down, the evident quasielastic peaks of Raman spectra occur only in the crystal with x = 0.065, which is due to the contribution of orbital ordering between xz and yz Fe 3d orbitals, as we reported in another work. Here, we analyze the Eg phonon at 128 cm?1, which has the same function form of its Raman tensors as those of xz and yz Fe 3d orbitals in these two crystals respectively. Unlike their electronic continuums, no anomalies are found in the Eg phonons of these two samples, which simply follows the expressions corresponding to the anharmonic phonon decay into acoustic phonons with the same frequencies and opposite momenta. Our results indicate that the structural and magnetic phase transition might be completely suppressed by chemical doping and there is not any indication of coupling between charge nematicity and Eg phonon mode from our experimental results, which is consistent with the results in our previous work.