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Convolutional neural networks (CNNs) based super-resolution (SR) methods have achieved remarkable progress in recent years. Most of these methods assume that the degradation is known and fixed, such as bicubic downsampling. However, the performance of CNNs-based methods suffers from a severe drop when the actual degradation mismatch the training one. This paper proposes a prior correction network (PCNet) to solve the blind SR problem, which makes CNNs-based super-resolvers trained in a fixed blur kernel but applied to other unknown blur kernels. The PCNet consists of a kernel estimation network, a correction filter module, and a correction refinement network. The kernel estimation network aims to estimate unknown blur kernel from the input low-resolution (LR) image. The correction filter module then transfers the estimated degraded domains to adapt to specific degradations (e.g., bicubic downsampling). Finally, the correction refinement network adjusts the corrected LR image to eliminate the influence of blur kernel mismatch or misestimate. Experimental results on diverse datasets show that the proposed PCNet, combined with existing CNNs-based SR methods, outperforms other state-of-the-art algorithms for blind SR. Code is available at: \url{ https://github.com/caoxiang104/PCNet }. [ABSTRACT FROM AUTHOR]

Recently, depth map super-resolution (DSR) has obtained remarkable performance with the development of convolutional neural networks (CNNs). High-resolution (HR) depth map can be inferred from a low-resolution (LR) one with the guidance of its corresponding HR intensity image. However, most of the existing CNNs-based methods unilaterally transfer structures information of guidance image to the input depth map, which ignores the corresponding relations between the depth map and the intensity map. In this paper, we propose a novel dual auto-encoder attention network (DAEANet) for DSR. The proposed DAEANet includes two auto-encoder networks, where guidance auto-encoder network (GAENet) and target auto-encoder network (TAENet) aim to extract feature information from intensity image and depth map. Specifically, all auto-encoder networks are similar and trained simultaneously to ensure structural consistency. Furthermore, to preserve the structure information in the process of training, the attention mechanism is employed to our DAEANet. Extensive experiments on several popular benchmarks show that the proposed DAEANet outperforms existing state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

Lithium metasilicate and disilicate glass-ceramics (LMGC and LDGC) are attractive dental materials but poor surface quality produced in current milling/grinding is a technical bottleneck. This paper reports on the microgrinding characteristics and mechanisms of LMGC and LDGC using micro-pencil diamond tools at different conditions. Surface quality was assessed using 3D laser confocal microscopy in terms of comprehensive roughness parameters. A combination of brittle and localized ductile removal mixture and brittle fracture was featured on the microground LMCG and LDGC surfaces identified through microscopic examination. The generation of brittle and localized ductile areas significantly depended on the diamond grit size and the depth of cut, resulting in different surface asperities. Better surface quality was achieved with reduced diamond grit size and depth of cut. The nanoscale maximum grit cutting depth in microginding achieved the best average and maximum roughness values of 0.241 ± 0.009 μm and 4.380 ± 0.861 μm for LMGC with approximately 80% and 60% reductions in comparison with dental CAD/CAM milling, respectively. Microgrinding of LDGC also achieved the best average and maximum roughness values of 0.168 ± 0.013 μm and 3.693 ± 0.467 μm with more than 90% improvement compared with simulated conventional grinding, simplifying the manufacturing procedure for LDGC restorations. Microgrinding also produced the kurtosis and skewness for both materials comparable to human teeth. More diamond tool wear occurred in microgrinding of high-strength LDGC than low-strength LMGC. Although microgrinding of multiphase LMCG and LDGC in ductile regime can be challenging due to microstructural diversity, the technique can advance current CAD/CAM milling/grinding for high-quality shaping of high-strength ceramic restorations. [Display omitted] • The microgrinding mechanisms of lithium metasilicate/disilicate glass-ceramics (LMGC and LDGC) were elucidated. • A combination of brittle and localized ductile removal mixture and brittle fracture was dominant in microgrinding of multi-phase ceramics. • Microstructures, mechanical properties and microgrinding conditions remarkably influenced removal mechanisms and quality. • Microgrinding of LMGC and LDGC achieved huge reductions in roughness and comparable kurtosis and skewness to human teeth. • Microgrinding may advance dental CAD/CAM milling techniques and simplify the prodcution of high-strength ceramic restorations. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel optical hollow-fiber with high photocatalytic activity was developed. • A photocatalyst of Er3+:YAlO 3 /SiO 2 /TiO 2 was graded on the surface of the fibers. • Photocatalytic activity of a single fiber toward degradation of 4-CP was tested. • Optimized operating conditions to enhance 4-CP degradation were investigated. • Photocatalytic fiber shows high activity toward degradation of 4-CP. Abstract We present a novel UV–visible-light photocatalytic optical hollow-fiber in which a hollow optical fiber (HOF) and TiO 2 -based composite are coupled for enhancement of photocatalytic activity toward degradation of 4-chlorophenol (4-CP). A HOF was coated with a TiO 2 -based composite composed of Er3+:YAlO 3 /SiO 2 /TiO 2 (EYST) and acting as the photocatalytic element. The EYST coating showed good light-inducing capacity at the fiber-coating interface and high photocatalytic activity driven by UV–visible light. The photocatalytic activity of the fabricated photocatalytic HOFs was investigated for degradation of 4-CP in aqueous solution in the wavelength spectrum of 360–780 nm. Examined were the effects of the EYST coating gradient and reactor operating conditions (pH and temperature) on the degradation of 4-CP. The EYST-coated HOF significantly enhanced the 4-CP degradation, dechlorination, and mineralization, compared to pure TiO 2 -coated HOF and EYST-coated solid optical fibers. Specifically, high photocatalytic activity was obtained when the EYST coating thicknesses at the HOF’s incident end and HOF’s hemispherical end were 10 and 160 μm, the pH was 6.0, and temperature was 55 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel system for intimately coupled photocatalysis and biodegradation (ICPB) was developed and tested. • Rapid phenolic degradation and phototrophs growth via emitted visible light were achieved by photocatalytic fibers. • Rhodococcus and Pseudomonas in biofilm were enriched to biodegrade photocatalytic products. • The photocatalytic generation of hydroxyl free radicals was helped by O 2 production from phototrophs. • The rapid and sustainable degradation of high concentrations of phenolic compounds was enabled by ICPB system. We developed and demonstrated a novel intimately coupled photocatalysis and biodegradation (ICPB) system. The ICPB system was comprised of photocatalytic optical hollow-fibers (POHFs) coated with Ag-loaded GeO 2 and N-doped TiO 2 photocatalyst, along with a biofilm that included phototrophic and heterotrophic microorganisms. The POHFs exhibit high UV–visible photocatalytic activity to degrade phenolic compounds rapidly and stably, decrease toxicity, generate readily biodegradable products, and emit visible light for biofilm growth and O 2 production by phototrophs. O 2 produced by the phototrophs was transferred to the POHFs, helping generate hydroxyl free radicals for photocatalysis. The biofilm, which became enriched in Rhodococcus and Pseudomonas , maintained rapid and stable biodegradation of photocatalytic products from the phenolics. Thus, the synergism among photocatalysis, biodegradation, and photosynthesis in the novel ICPB system provided an efficient means to rapidly and sustainably degraded and mineralized high concentrations of phenolic compounds. [ABSTRACT FROM AUTHOR]

The automatic and objective medical diagnostic model can be valuable to achieve early cancer detection, and thus reducing the mortality rate. In this paper, we propose a highly efficient multi-level malignant tissue detection through the designed adversarial CAC-UNet. A patch-level model with a pre-prediction strategy and a malignancy area guided label smoothing is adopted to remove the negative WSIs, with which to lower the risk of false positive detection. For the selected key patches by multi-model ensemble, an adversarial context-aware and appearance consistency UNet (CAC-UNet) is designed to achieve robust segmentation. In CAC-UNet, mirror designed discriminators are able to seamlessly fuse the whole feature maps of the skillfully designed powerful backbone network without any information loss. Besides, a mask prior is further added to guide the accurate segmentation mask prediction through an extra mask-domain discriminator. The proposed scheme achieves the best results in MICCAI DigestPath2019 challenge 1 1 https://digestpath2019.grand-challenge.org/. on colonoscopy tissue segmentation and classification task. The full implementation details and the trained models are available at https://github.com/Raykoooo/CAC-UNet. [ABSTRACT FROM AUTHOR]

This article studies the issue of uniform synchronization for chaotic dynamical systems via event-triggered impulsive control (ETIC). The synchronization scheme is executed by designing ETIC with three levels of event-triggering conditions. Under the designed ETIC, the uniform exponential synchronization is achieved for master–slave chaotic systems. It shows the uniform synchronization via ETIC is robust with respect to time delays in ETIC. Moreover, the notions including rate of control and cost of control are proposed for comparisons with uniform synchronization via classic impulsive control (CIC) which is time-triggered impulsive control. The chaotic Lorenz system is used to test the performances of uniform synchronization via ETIC and CIC. The specific ETIC and CIC for uniform synchronization of master–slave Lorenz systems are designed and the numerical simulations of synchronizations via ETIC and CIC are given. It is shown that from the number of control, the rate of control, and the cost of control, ETIC has obvious advantages than CIC for uniform synchronization of master–slave Lorenz systems. • A synchronization scheme via event-triggered impulsive control (ETIC) is proposed. • The synchronization via ETIC is executed when one of state-based events is triggered. • The classic impulsive synchronization is significantly improved via ETIC. • The synchronization via ETIC is robust with respect to time-delays. • Lorenz systems are used to verify the performances of synchronization via ETIC. [ABSTRACT FROM AUTHOR]

• Depositing catalysts on hydrogen gas-transfer membranes in-situ created a homogeneous bimetallic layer. • Bimetallic palladium plus indium nanoscale films on hydrogen gas-transfer membranes enabled nitrate reduction. • Nanocatalyst oxidation must be avoided to retain nitrate removal activity. • Irreversible nanocatalyst attachment was necessary for sustained nitrate removal. Catalytic hydrogenation of nitrate in water has been studied primarily using nanoparticle slurries with constant hydrogen-gas (H 2) bubbling. Such slurry reactors are impractical in full-scale water treatment applications because 1) unattached catalysts are difficult to be recycled/reused and 2) gas bubbling is inefficient for delivering H 2. Membrane Catalyst-film Reactors (MCfR) resolve these limitations by depositing nanocatalysts on the exterior of gas-permeable hollow-fiber membranes that deliver H 2 directly to the catalyst-film. The goal of this study was to compare the technical feasibility and benefits of various methods for attaching bimetallic palladium/indium (Pd/In) nanocatalysts for nitrate reduction in water, and subsequently select the most effective method. Four Pd/In deposition methods were evaluated for effectiveness in achieving durable nanocatalyst immobilization on the membranes and repeatable nitrate-reduction activity: (1) In-Situ MCfR-H 2 , (2) In-Situ Flask-Synthesis, (3) Ex-Situ Aerosol Impaction-Driven Assembly, and (4) Ex-Situ Electrostatic. Although all four deposition methods achieved catalyst-films that reduced nitrate in solution (≥ 1.1 min−1gPd−1), three deposition methods resulted in significant palladium loss (>29%) and an accompanying decline in nitrate reactivity over time. In contrast, the In-Situ MCfR-H 2 deposition method had negligible Pd loss and remained active for nitrate reduction over multiple operational cycles. Therefore, In-Situ MCfR-H 2 emerged as the superior deposition method and can be utilized to optimize catalyst attachment, nitrate-reduction, and N 2 selectivity in future studies with more complex water matrices, longer treatment cycles, and larger reactors. [ABSTRACT FROM AUTHOR]

• Mechanical stress fields during micro-/nano- machining were integrated for surface integrity. • Flexible nanoscale-bonding and hydrodynamic pressure restrains cutting stress and tool vibration. • It decreases roughness, residual stress and SSD to polished ones in micro-shape diamond grinding. • The machined residual stress related to metal elastic modulus is more greatly improved with larger hardness. The micron-scale fixed-abrasive machining can assure micro-shape accuracy through mechanical cut removal and copying, but the machined surface integrity depends on the nanoscale loose-abrasive machining without mechanical stress concentration. Hence, the mechanical stress fields are synthesized by the hybrid machining of loose-Al 2 O 3 -abrasive machining and fixed-diamond-abrasive machining. The objective is to improve the surface integrity in the mechanical machining of difficult-to-cut metals. In order to hold the loose-abrasive in fixed-abrasive mechanical machining, the bonding behaviour and the hydrodynamic pressure were first analysed in relation to flow viscosity and fixed-abrasive-tool rotation, respectively. In the hybrid machining, the surface formation was then modelled in relation to mechanical stress distribution, fixed-abrasive-tool vibration, hydrodynamic pressure, etc. Finally, the surface integrity was investigated in micro-machining of die steel, titanium alloy and Inconel alloy, respectively. It is shown that the nanoscale hydrated particle cluster flexibly bonds the loose-abrasive with the hydrodynamic pressure beyond the critical tool rotation. It can absorb the micron-scale tool vibration to the surface formation, fixed-abrasive wear without ground traces and micro-cut edge burrs. The resulted homogeneous stress also can restrain the uneven residual stress derived from the cut copying of fixed-abrasive machining. The hybrid machining decreases the subsurface damage (SSD), residual compressive stress and surface roughness to the polishing ones in micro-shape grinding, but it is subject to the nanometre-scale size of loose-abrasive, the hydrodynamic pressure and the micron-scale cutting depth of fixed-abrasive. The fixed-abrasive wear rate is higher with larger metal hardness, and the residual stress associated with elastic modulus is more greatly improved. As a result, die steel shows better machinability with a low fixed-abrasive wear rate and residual stress compared to titanium alloy and Inconel alloy. [Display omitted] [ABSTRACT FROM AUTHOR]