Character Time-series Matching For Robust License Plate Recognition

Automatic License Plate Recognition (ALPR) is becoming a popular study area and is applied in many fields such as transportation or smart city. However, there are still several limitations when applying many current methods to practical problems due to the variation in real-world situations such as light changes, unclear License Plate (LP) characters, and image quality. Almost recent ALPR algorithms process on a single frame, which reduces accuracy in case of worse image quality. This paper presents methods to improve license plate recognition accuracy by tracking the license plate in multiple frames. First, the Adaptive License Plate Rotation algorithm is applied to correctly align the detected license plate. Second, we propose a method called Character Time-series Matching to recognize license plate characters from many consequence frames. The proposed method archives high performance in the UFPR-ALPR dataset which is \boldmath$96.7\%$ accuracy in real-time on RTX A5000 GPU card. We also deploy the algorithm for the Vietnamese ALPR system. The accuracy for license plate detection and character recognition are 0.881 and 0.979 $mAP^{test}$@.5 respectively. The source code is available at https://github.com/chequanghuy/Character-Time-series-Matching.gi

Polarization modulation by vanadium dioxide on metallic substrates

Vanadium dioxide (VO2) undergoing phase transition is known alters the polarization state of light in reflection owing to large changes in complex refractive indices. While this effect is promising for optical modulation applications, the usual VO2 films on dielectric substrates tend to offer limited tunability for polarization modulation. In this paper, we show that metallic under-layers greatly enhance the performance by widening the spectral range and include visible wavelengths, by increasing the polarization modulation amplitude, and by widening the range of workable incidence angles. The imaginary part of the refractive index in the metallic layer is found to increase the relative phase shifts between s- and p-components of polarization as well as increasing the reflectance

Prediction of delamination strength at interface between thin film and substrate by cohesive zone model

An electronic device consists of multi-layered submicron-thick films, and delamination often takes place at an interface edge because of the stress singularity near the edge. Since the stress singularity at an interface edge depends on the edge shape, the fracture mechanics concept cannot be used to compare the delamination strength between the components with different shapes. This paper aims to predict the delamination strength at the interface edge with arbitrary shape using a cohesive zone model. Two different experiments are conducted for a gold thin film on a silicon substrate to calibrate the cohesive law. The validity of the approach is then discussed

Four new species of Perilimnastes (Sonerileae, Melastomataceae) from Vietnam

Perilimnastes is a genus currently treated in the polyphyletic Phyllagathis. Recent phylogenomic analyses have identified a morphologically cohesive lineage referred to as the Phyllagathis (raphides) clade, which should be excluded from Phyllagathis and treated as a distinct genus under the name Perilimnastes. Morphological and phylogenomic data have confirmed that four new species collected from Vietnam are part of the Phyllagathis (raphides) clade. They are described herein as Perilimnastes multisepala, P. setipetiola, P. uniflora, and P. banaensis. Perilimnastes multisepala is phylogenetically closest to Phyllagathis setotheca, and morphologically to P. fruticosa and P. stenophylla, but is distinct in the 4- to 8-lobed calyx, 28 × 9 mm, apically long acuminate petals, and 1–2 mm pedicel at fruiting stage. Perilimnastes setipetiola, P. uniflora, and P. banaensis are phylogenetically most closely related. Perilimnastes uniflora is characterized by its prostrate habit, small size, glabrous, obovate to obovate-lanceolate leaf blade, and solitary flower. Perilimnastes setipetiola and P. banaensis resemble each other in habit, leaf size and shape, and sessile or near sessile inflorescences but can be easily distinguished by the indumentum of the stems and leaves

Clinical and Microbiological Features of Pediatric Endopthalmitis After Open Globe Injury in the North of VietNam

BACKGROUND: Pediatric endophthalmitis after open-globe injury had its clinical features, microbiological profile different from those in aldults. In Viet Nam, there was no report on the clinical and microbiological characteristic of pediatric posttraumatic endophthalmitis. Therefore, we conduct this study. AIM: To describe clinical features, ultrasound results, gram stain and culture results of endophthalmitis in pediatric open globe injuries. METHODS: Prospective non-controlled study. Case series of 30 eyes presenting with post-traumatic endophthalmitis between 2015 and 2016 were reviewed. RESULTS: Mean age was 8.03 ± 3.99 years. Metallic and organic etiologies were most common causes for injuries (n = 11). 27 cases had penetrating corneal trauma. Dense opaque vitreous was seen in 25 eyes. Retinal necrosis < 1 quadrant and chorioretinal abscess > 1 quadrant were most common fundus lesions. Dense vitreous opacity on ultrasound was most common (n = 28). Gram stain bacteria positivity was 93.3%, gram-positive were isolated in 63.3%. Vitreous samples were more often positive than aqueous (P = 0,002). CONCLUSION: Posttraumatic endophthalmitis in children is more common in boys aged 6-10 years and most often caused by injury with metallic and organic matter. Culture results were very low. Vitreous samples were more often positive than aqueous. Gram-positive bacteria were the most common causative organism

ẢNH HƯỞNG CỦA TỈ LỆ Ba/Ti LÊN ĐẶC TRƯNG CỦA HẠT NANO BaTiO3 TỔNG HỢP BẰNG PHƯƠNG PHÁP THỦY NHIỆT

Highly dispersed BaTiO3 nanospheres with a uniform particle size were synthesized with the hydrothermal method. The influence of Ba/Ti molar ratios on the formation of BaTiO3 nanospheres was studied by analyzing the XRD and SEM data. The TiO2·H2O synthesized with the sulfuric acid method assisted by ultrasonication was used as a starting material. Highly dispersed BaTiO3 nanospheres with an average size of about 100 nm were obtained at 200 °C in 12 hours with a Ba/Ti ratio of 1.5. The Ba/Ti ratios have a strong influence on the formation of nano BaTiO3 and the phase transition. The particle size increases with the Ba/Ti ratio, while the uniformity decreases.Vật liệu BaTiO3 nano hình cầu phân tán cao với kích thước đồng đều được tổng hợp bằng phương pháp thủy nhiệt. Ảnh hưởng của tỉ lệ mol Ba/Ti lên sự hình thành vật liệu được nghiên cứu bằng cách phân tích dữ liệu XRD và SEM. TiO2·nH2O tổng hợp bằng phương pháp axit sunfuric với sự hỗ trợ sóng siêu âm được sử dụng làm nguyên liệu ban đầu. Vật liệu nano BaTiO3 hình cầu với độ phân tán cao và kích thước trung bình khoảng 100 nm đã thu được tại 200 °C trong 12 giờ với tỉ lệ Ba/Ti = 1,5. Tỷ lệ Ba/Ti ảnh hưởng mạnh đến sự hình thành BaTiO3 nano hình cầu với quá trình chuyển pha. Khi tăng tỉ lệ Ba/Ti, kích thước hạt tăng và tính đồng nhất giảm

Silicon quantum-dots-based optical probe for fluorometric detection of Cr6+ ions

In this report, silicon quantum dots (SiQDs) with the NH2 functional group were synthesized with the hydrothermal method. The as-prepared SiQDs exhibit a strong fluorescence emission peak               at 441 nm when excited at 355 nm and are effectively quenched upon adding Cr6+ ions. Hence, SiQDs were used as an optical probe to detect Cr6+ ions in solutions. The crystal structure of SiQDs was characterized by using X-ray diffraction (XRD). The Fourier-transform infrared spectroscopy (FT-IR) was used to determine the linker groups on the SiQDs surface. The fluorescence spectroscopic technique with an excitation wavelength of 355 nm was used to quantify the Cr6+ ion concentration in the solutions in the range of 0.1–1000 µM. Competition from common coexisting ions, such as K+, Na+, Al3+, Zn2+, and Pb2+, was ignorable. The test with actual samples showed good linearity for the Cr6+ concentration range of 0.1–50 µM

The effect of polyamine 70000 (BT70) on the zinc plating process in the non-cyanide alkaline plating bath

The effect of polyamine having molecular weight 70,000u (BT70) in the non-cyanide alkaline plating bath on the morphological zinc electrodeposited coating was investigated. The obtained results from the reflectance of electrodeposited zinc coating by a suitable range of electro-current density and SEM images showed that BT70 had effect on the zinc plating in comparison with the zinc deposits from plating bath without BT70. The electrodeposited coating surface was rough and poor adhesion. However, adding BT70 into the plating bath led to the surface roughness of electrodeposited coating and grand size being reduced. Zinc electrodeposited coating from a plating bath containing BT70 at 0.5 g/L, respectively, experienced the highest reflectance, equal 46 % of the electrodeposited coating from the bath containing commercial additives. Hull method showed that the zinc deposited coating surface became smoother with the presence of polyamine in non-cyanide alkaline zinc plating solution. The zinc deposited coating had a semi-gloss scope at 10 A/dm2. If the BT70 content increased, the semi-gloss scop and the gloss of samples’ surfaces also grew up. Keywords. Polyamine, additive, non-cyanide alkaline zinc plating, zinc coating