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Surface flaw inspection is of great importance for quality control in the field of manufacture. In this paper, a novel surface flaw inspection algorithm is proposed based on adaptive multiscale image collection (AMIC) using convolutional neural networks. First, the inspection networks are pretrained with ImageNet data set. Second, the AMIC is established, which consists of adaptive multiscale image extraction and with-contour local extraction from training images. Through the AMIC, the training data set is greatly augmented, and labels of images can be accomplished automatically without artificial consumption. Then, transfer learning is performed with the AMIC established from training data set. Finally, an automatic surface flaw inspection instrument for large-volume metal components embedded with the proposed inspection algorithm is designed. Experiments with small metal components are performed to analyze the influence of parameters, and comparative experiments are carried out. The inspecting precisions for indentation, scratch, and pitted surface of the proposed method are 97.3%, 99.5%, and 100%, respectively. The experimental results demonstrate the effectiveness of the proposed method in the detection of various surface flaws. [ABSTRACT FROM AUTHOR]

We report electrical and magnetic measurements of an optimally doped Eu(Fe0.88Ir0.12)2As2 crystal which shows superconductivity at Tsc = 22 K and magnetic ordering of the Eu2+ spins below 20 K. The results suggest that the Eu2+ spins lie flat ferromagnetically in the ab plane at Tabm = 20 K, and then tilt toward the c-axis at Ttiltm = 17.4 K. The isothermal magnetization loop at low temperatures shows both ferromagnetic behavior and superconducting characteristics, unambiguously demonstrating the coexistence of ferromagnetism and superconductivity. The upper critical field measured is remarkably reduced, as compared to other Fe-based superconductors with the same Tsc, and it exhibits abnormal temperature dependence featured by the existence of an inflection point around Tabm, where the anisotropy ratio γ (≡ H∥abc2/H∥cc2) shows a minimum value smaller than 1.0. These observations can be explained by a ferromagnetic exchange field of ∼30 T which tilts its direction toward the c-axis below Ttiltm. The strong internal field, much higher than the intrinsic lower critical field expected, leads to the absence of Meissner state, which is confirmed by the magnetic measurements under ultra-low fields. [ABSTRACT FROM AUTHOR]

We report the effect of Sr substitution in an antiferromagnetic insulator LaMnAsO by the measurements of electrical resistivity, Hall coefficient, Seebeck coefficient and magnetization. Upon Sr doping to its limit x∼0.10, the room temperature resistivity drops by five orders of magnitude down to ∼0.01Ω·cm, and the temperature-dependent resistivity shows essentially metallic behavior. Hall and Seebeck measurements confirm consistently that the insulator-to-metal transition is due to hole doping. The room temperature Seebeck coefficient for the metallic samples is as high as ∼240 μ V/K, making the system a possible candidate for thermoelectric applications. [ABSTRACT FROM AUTHOR]

• In this study, mir-497 was introduced into the research field of human medulloblastoma cells for the first time. It was found that mir-497 was highly expressed in human medulloblastoma cells, and its expression level was closely related to the prognosis of human medulloblastoma, suggesting that mir-497 is a new prognostic marker of human medulloblastoma. • This study confirmed for the first time that mir-497 plays an important role in the regulation of invasion of human medulloblastoma, which helps to deepen the understanding of the molecular mechanism of the occurrence and development of human medulloblastoma. • Mir-497 / ARHGDIA axis is involved in the migration and invasion of human medulloblastoma Daoy cell line in vitro. To further investigate the effects of miR-497 on the biological behavior of human medulloblastoma cell line in vitro. Human medulloblastoma cell lines, Daoy and D341, were used in this study, and the miR-497 expression in the cells was measured by Quantitative PCR with fluorescence. The Daoy cells were divided into the mimics group (Daoy cells treated with mimics), inhibitor group (Daoy cells treated with inhibitor), normal Daoy cells, ARHGDIA siRNA group (Daoy cells transfected with ARHGDIA siRNA), ARHGDIA control group (Daoy cells did not receive any treatment), and negative control group (normal cells transfected with ARHGDIA siRNA). The expression of miR-497 and ARHGDIA mRNA was measured by Quantitative PCR with fluorescence, while the level of ARHGDIA protein was measured by Western blot. The binding capability of ARHGDIA and miR-497 was assessed by luciferase assay, the migration of cells was assessed by wound healing assay, and the invasion of cells was assessed by Transwell assay. Compared to D341 cells, the miR-497 level was significantly higher in the Daoy cells (P < 0.01). The dual-luciferase reporter assay showed that miR-497 targets ARHGDIA. Transfecting the normal Daoy cells with miR-497 mimics significantly reduced the expression of ARHGDIA protein (P < 0.05), while transfecting normal Daoy cells with miR-497 inhibitor significantly increased the expression of ARHGDIA protein (P < 0.05). Consequently, the migration and invasion capability of cells increased significantly after transfection with miR-497 mimic (P < 0.05), and decreased significantly after transfection with miR-497 inhibitor (P < 0.05). In addition, the migration and invasion capabilities of the cells also increased significantly after transfection with ARHGDIA siRNA (P < 0.05). miR-497/ARHGDIA axis participates in the in vitro migration and invasion of human medulloblastoma cell lines. [ABSTRACT FROM AUTHOR]

Machine vision image quality is significantly affected by illumination. Uniform illumination of a rectangular target surface requires a function for evaluating the illumination system. In this study, based on an LED array light source illuminance model, such an evaluation function was established. Further, the influence of the light source's structure on illumination was analyzed using a single-factor analysis method to determine the boundary conditions, and it was then solved using a genetic algorithm to finalize the structural design. An experimental platform was built to measure the illuminance uniformity. The experimental results were consistent with the numerical results, verifying the effectiveness and feasibility of the proposed illumination method. Thus, this research provides a theoretical reference for the illumination of a rectangular target surface for vision-based detection.

Ba0.6K0.4Fe2Se3 (BKFS) single crystals were investigated by means of measurements of powder x-ray diffraction, temperature-dependent resistivity, anisotropic dc magnetization, ac magnetic susceptibility and specific heat. The powder x-ray diffraction indicates staggered iron displacements along the ladders with short and long Fe-Fe bond lengths (2.64(2) and 2.91(2) Å) variation. The resistivity of BKFS exhibits variable range hopping behavior with ln(ρ) ~ T(-1/2) at low temperature. The magnetic susceptibility χ(T) exhibits a sharp cusp at around 20 K in a zero-field-cooled process. The frequency-dependent ac magnetic susceptibility reveals that the cusp feature is attributable to spin glass behavior. The anisotropic ac magnetic susceptibility indicates that BKFS is probably an anisotropic Heisenberg-like spin glass with its easy magnetization plane perpendicular to the chain direction. The specific heat also supports an insulating and spin glass ground state. Extended Curie-Weiss behavior above 40 K was observed with a reduced effective moment (μ(eff) = 1.66 μ(B)/Fe for H is perpendicular to b and μ(eff) = 1.82 μB/Fe for H is parallel to b) in BKFS, which is close to the spin-only magnetism with S=1/2.