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Image denoising has been a knotty issue in the computer vision field, although the developing deep learning technology has brought remarkable improvements in image denoising. Denoising networks based on deep learning technology still face some problems, such as in their accuracy and robustness. This paper constructs a robust denoising network based on a generative adversarial network (GAN). Since the neural network has the phenomena of gradient dispersion and feature disappearance, the global residual is added to the autoencoder in the generator network, to extract and learn the features of the input image, so as to ensure the stability of the network. On this basis, we proposed an optimization algorithm (OA), to train and optimize the mean and variance of noise on each node of the generator. Then the robustness of the denoising network was improved through back propagation. Experimental results showed that the model’s denoising effect is remarkable. The accuracy of the proposed model was over 99% in the MNIST data set and over 90% in the CIFAR10 data set. The peak signal to noise ratio (PSNR) and structural similarity (SSIM) values of the proposed model were better than the state-of-the-art models in the BDS500 data set. Moreover, an anti-interference test of the model showed that the defense capacities of both the fast gradient sign method (FGSM) and project gradient descent (PGD) attacks were significantly improved, with PSNR and SSIM values decreased by less than 2%.

The bouncing process of an irregular object falling on the ground contains many interesting mechanical problems. The article investigated the bounce height of a capsule-shaped object when it falls on the ground. The variation of three physical quantities, namely the angle of the object, the linear velocity of the center of mass and the angular velocity relative to the center of mass when it fell on the ground are studied. According to the limit condition of friction, the three-dimensional phase diagram of the above three physical quantities was drawn when the fall height of the capsule-shaped object and the bounce height was equal. The movement of the capsule-shaped object is captured by using two cameras positioned perpendicular to each other. The trajectory was tracked by TRACKER software to obtain the fall height and bounce height of the capsule. When the bounce height was higher than the fall height, it was marked with a red dot. If both heights were equal, it was marked with a black dot. Otherwise, it was marked with a blue dot. Different types of experimental data points are plotted in the phase diagram. A large amount of random experimental data verifies the correctness of the theory.

In this work, the NHC-catalyzed Michael/Mannich/lactamization cascade reaction of enals with either indole-2-carboxaldehyde-derived aldimines or indole-7-carboxaldehyde-derived aldimines is describ...

The budding deuteriodifluoromethyl group (CF2D) is a potentially significant functional group in medicinal chemistry. Herein, we investigated t-BuOK-catalyzed H/D exchange reaction of difluoromethylarenes in DMSO-d6 solution. The method provides excellent deuterium incorporation at the difluoromethyl group. Meanwhile, the effect of a trace amount of D2O in DMSO-d6 solution on the deuteration reaction was also investigated.

Five m-phenylene-embedded cycloparaphenylenes m3[9]CPP 1-5 were synthesized by the platinum-mediated cyclooligomerization strategy with high overall yields. The structures of m3[9]CPP 1-3 were determined by X-ray diffraction analysis. Compared to [9]CPP, m3[9]CPP 1 caused a significant blueshift in the UV-vis absorption and fluorescence spectra. This result shows that the radial π-conjugation is distorted and partially interrupted. The photophysical properties of m3[9]CPP 1 were further tuned by the introduction of various substituents for m3[9]CPP 2-5. Methoxy group substitution at m-phenylene did not change the photophysical properties significantly. Replacement of m-phenylene by tetrafluoro-m-phenylene achieved a significant blueshift. When the carboxyl group was embedded at m-phenylene or the methoxy group was embedded at p-phenylene, significant redshifts were observed with blue color emission. Theoretical calculations revealed that the decrease in the HOMO-LUMO gap in m3[9]CPP 4 and 5 is favorable for the redshift of the fluorescence spectrum.

Ruthenium-catalyzed aromatic H/D exchange in [D4]acetic acid has been developed. By using N-heteroarenes as directing groups, both ortho and meta positions are selectively deuterated with high leve...

In this work, the NHC-catalyzed Michael/Mannich/lactamization cascade reaction of enals with either indole-2-carboxaldehyde-derived aldimines or indole-7-carboxaldehyde-derived aldimines is described. This protocol enables the rapid assembly of optically active pyrroloindolones and pyrroloquinolinones derivatives under mild conditions with high yields, excellent enantioselectivities, and a broad substrate scope.

Nanophthalmos is a clinical phenotype of simple microphthalmos, in which the anterior and posterior segments of the eyeball do not develop into a normal size without other major ocular or systemic anomalies. Typical clinical manifestations of nanophthalmos include short axial length, thickened sclera, small cornea, shallow anterior chamber, and increased lens-to-eye volume ratio. Currently, there is a lack of recognized diagnostic criteria for nanophthalmos. With the development of eye examination technologies, such as biological measurement and imaging examination, visualization and quantification of the eyeball’s shape and structure in nanophthalmos can be realized. New clinical features have been reported, which are of great significance for diagnosing and treating nanophthalmos. This review introduces the related concepts of nanophthalmos and the new developments in its clinical characterization.

When calculating RCS using the Graphical Electromagnetic Algorithm (GRECO), Firstly we must obtain the coordinate values and normal vectors of each point on the target illumination surface, which is limited to the computer hardware conditions. So when we calculating RCS at high frequencies often accompanied by insufficient pixel accuracy, therefore it can affect the calculation accuracy. The method of turning straight into a curve adopts a curved surface as close as possible to the real situation instead of the facet information represented by pixels, thereby improving the calculation accuracy of the model at high frequency.

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Ruthenium-catalyzed aromatic H/D exchange in [D

A novel and convenient strategy for the enantioselective synthesis of γ-lactam derivatives via N-heterocyclic carbene catalyzed formal [3 + 2] annulation of enals with 2-aminoacrylates is disclosed. This activation mode provides a complementary approach to the synthesis of various γ-lactam derivatives in good yields with excellent diastereo- and enantioselectivities. In this process, two consecutive stereocenters are constructed, and a quaternary carbon center is also established.

The piezo-phototronic effect, as an effective interfacial regulating strategy, utilizes piezoelectric polarization charges present at the local junction/interface to modulate the optoelectronic processes of charge carrier such as generation, separation, transport and recombination, which is in close relationship with crystal orientation of the piezoelectric semiconductors. In this work, the piezo-phototronic effect is utilized to modulate the photoresponse performances of a-axis GaN microwire/p-polymer inorganic/organic hybrid photosensor. The output photocurrent experiences an increase followed by a decrease as increasing compressive strain, while it decreases monotonously as increasing tensile strain, resulting in a maximum values at each light intensity under a certain compressive strain. Besides, the modulation of photoresponse by the piezo-phototronic effect is more significant under weak illumination condition. By applying a −0.32% compressive strain, the sensitivity and responsivity of the hybrid photosensor are greatly enhanced by 508% and 354%, respectively. Two independent processes that affect photogenerated charge carriers separation and transport by strain are discovered, which is different from those normally investigated in c-axis hybrid nanostructures.

The brittleness of poly(lacticacid) (PLA) is a major drawback for its wide application. In this study, a super-flexible PLA material was prepared by reactive blending of PLA with poly(ethylene-glycidyl methacrylate) (EGMA), and the weight ratio was fixed at 95 : 5. The investigation showed that the PLA/EGMA blend had limited interfacial compatibility. The strong interfacial interaction and fine dispersion of EGMA particles were obtained by using initiator DCP, which it had been demonstrated could accelerate the reaction efficiency between PLA and EGMA. The elongation at break of the PLA/EGMA/DCP blend was remarkably improved, about 58 folds that of neat PLA. More importantly, its outstanding tensile strength and transparency were definitely maintained as that of neat PLA. Our work provides an effective method to largely improve the flexibility of PLA without sacrificing its stiffness and transparency, which is very important for the wide application of PLA materials.

Summary H/D exchange at formyl groups is the most direct approach for the synthesis of deuterated aldehydes. Platinum-group metal complexes have been employed to catalyze this transformation, with significant substrate scope limitations. Although N-heterocyclic carbenes can also activate the C–H bond of aldehydes through the formation of Breslow intermediates, benzoin condensation and other C–C-bond-forming pathways have so far outpaced synthetically useful H/D exchange. Investigation of the reaction of aldehydes with 1,2,3-triazolylidenes has revealed the reversible formation of Breslow intermediates and the inhibition of the condensation steps in methanol solvent. 1,2,3-Triazolylidenes catalyze the H/D exchange of aryl, alkenyl, and alkyl aldehydes in high yields and deuterium incorporation levels using deuterated methanol as an affordable D source. The unique properties of these mesoionic carbenes (MICs) enable a streamlined preparation of deuterated synthetic intermediates and pharmacophores that are highly valuable as mechanistic and metabolic probes.

We report ultraviolet light emitting diode (LEDs) with polarization doped p-type layer. Fabricated LEDs with polarization doped p-type layer exhibited reduced forward voltage and enhanced light output power, compared to those with traditional p-type AlGaN layer. The improvement is attributed to improved hole concentration and the smooth valence band by the polarization enhanced p-type doping. Our simulated results reveal that this p-type layer can further enhance the performance of ultraviolet LEDs by removing the electron blocking layer (EBL).

To explore the clinical early-middle stage clinical effect of percutaneous spinal endoscopic with the technique of Broad Easy Immediate Surgery(BEIS) for lumbar spinal stenosis.The clinical data of 57 patients with lumbar spinal stenosis treated by surgery from June 2015 to June 2016 were retrospectively analyzed, including 32 cases treated by percutaneous spinal endoscopic with the technique of BEIS (minimally invasive group) and 25 cases by posterior approach of lumbar pedicle screws internal fixation and intervertebral disc excision with bone graft fusion surgery (open surgery group). The pre-operative general data such as age, Body Mass Index (BMI) and etc. were analysed and compared. The operation time, intraoperative blood loss, hospitalization time of the two groups were analyzed. Visual analogue score(VAS), Oswestry Disability Index(ODI), Japanese Orthopedic Association Score(JOA) of preoperative and at 1 week, 1 month, 3 months, 6 months after surgery were used to evaluate the clinical outcome of the two group.All the operations were successful and all the patients recovered smoothly without severe complications, all the wounds got good healing. The pain of the lumbar and lower limb had been improved after surgery. All the patients were followed up more than 6 months with an average of(10.65±3.38) months. There was no significant difference in general data such as age, BMI, and etc. between two groups(BEIS technique has the advantage of less trauma, less bleeding for lumbar stenosis when compared to open surgery. It can better alleviate the postoperative local lumbar pain, and early-middle clinical effect is equivalent to open surgery, so it can be used as a safe and effective surgical treatment for lumbar spinal stenosis.

As one of main layers in hybrid organic–inorganic perovskite solar cells (PSCs), electron transport materials (ETM) play an important role in getting high photoelectric conversion efficiency (PCE). Here, we investigate Al2O3/TiO2 hybrid materials as electron transmission layer in planar perovskite solar cells. The hybrid Al2O3/TiO2 material is proved to induce a better crystal quality of CH3NH3PbCl3−x I x perovskite layer as confirmed by X-ray diffractometer (XRD). The new-formed compact rough surface of ETM is responsible for the better excited electron transmission and light absorption, thus resulting in the improvement of short-circuit current (J sc). Meanwhile, the embedded Al2O3 plays a key role in shifting the conduction band edge of ETM, thereby leading to the improvement of photo-voltage. The optimal value is obtained with the test of sequential changing Al2O3/TiO2 concentration ratio. Compared to the device with pure TiO2 as ETM, the devices assembled with Al2O3/TiO2 hybrid ETM showed improvement in J sc (from 13.65 to 18.71 mA/cm2) as well as in V oc (from 0.95 to 1.00 V), which brings about 27.6% enhancement in PCE based on the multifunctional hybrid TiO2/ Al2O3 ETM.

This letter presents the morphology of femtosecond Bessel beams induced high-aspect-ratio structural change regions in bulk silicon carbide. An axion is engaged in transforming Gaussians beams to Bessel beams, which are then focused on the surface or below the surface of the sample by combination of a plano-convex lens and a microscope objective. The sample is scanned by the focused femtosecond Bessel beams at the preset patterns. Through this method, the high-aspect-ratio uniform laser induced structure change regions have been produced and the highest respect ratio can reach 206 with the depth of 330 μm, the width of 1.6 μm in optimized conditions of appropriate focusing position and pulse energy. This result is attributed to uniform energy distribution in the long propagation distance of Bessel beams with nondiffracting. This technique will have great potential applications to make high-aspect-ratio microgrooves in wide-gap and transparent materials.

We report the effects of thermal flow air post-treatment on the performance of solution-processed CH3NH3PbI3−xClx based planar solar cells under high relative humidity. It is found that the treatment process results in a significant enhancement in the power conversion efficiencies from 7.06 to 10.42%. The fill factor can be controlled in more than 0.7, with low values of the standard deviations. The change of shunt resistance and series resistance reflect that a high relative humid environment may be conducive to form good interfacial contact and decrease contact resistance of device, further enhance charge carrier lifetime among the layers interface, thus improving photovoltaic performance. Moreover, the PL intensity variations indicate that the appropriate temperature of thermal flow air post-treatment reducing the recombination of localized excitons of perovskite film, hence enhancing the charge separation and transport capability. Utilizing appropriate temperature thermal flow air post-treatment under high relative humidity, high efficiency solar cells with good reproducibility were achieved.

Parallel test is the key technology of the NxTest technology and the parallel test tasks scheduling is one of the important part of parallel test. The mathematical model of the problem was introduced, according to the advantage of solving the problem of dynamic scheduling with artificial bee colony algorithm; an approach of parallel test scheduling based on artificial bee colony algorithm is brought forward. An example was given, the result of simulation shows that this algorithm’s constringency fast and the result has a high precision, it is an efficient way of solving the problem of optimized parallel test tasks scheduling.

In order to analyze the behavior of piled raft foundations under vertical loadings, a simplified method called settlement compensation method (SCM) is proposed based on the basic principles in the code for design of building foundation of China. The effect of several influence factors of the SCM was investigated through an exemplar case. The applicability and accuracy of SCM was checked theoretically with a finite element analysis, and verified practically through a case study in which the results of settlement analysis of other methods were included for comparison.

To investigate the clinical efficacy of excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation.From June 2011 to June 2014, a total of 13 patients with tibia osteomyelitis were treated with excision of necrotic and infected tissues and external fixator technique in the first stage. There were 8 males and 5 females, ranging in age from 16 to 67 years old with an average of (37.3±14.3) years old. Within 6 to 8 weeks the induced membrane was formed and the induced membrane technique was applied to promote new bone forming in the second stage.Thirteen patients had no reinfection and achieved complete bone healing after 24 to 52 months follow-up. All the patients had satisfactory function.Excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation can provide satisfactory results.

This article proposes a framework of in-situ monitoring for anomaly detection of avionics, Uses the multi-variant Hotelling T2 statistics to form a quickly reference to the anomaly behavior. The proposed method can be used to solve the data driven Prognostics and Health Management problem to detect the anomaly behavior of equipment as well as the potential isolation and diagnosis of the symptoms of incoming faults. The article also gives a structure of an on-line test and monitoring system prototype, based on the legacy on-line test system, as well as developed a basic information gathering route and a multi-variant test based anomaly detection method. A fault injection based simulation experiment was formed to validate the performance of the system and method under consideration. The results shows that the proposed method has a solid mathematics fundamental and the advantages as well as good performance, worth to be spread.

In this paper, we design the FPGA-based reconfigurable intelligent instrument which has eight different functions through hardware reconfiguration and software reconfiguration. Hardware reconfiguration is realized through loading different configuration data for FPGA. Software reconfiguration is realized through using reconfigurable application frame technology. We also develop the software demo system of FPGA-based reconfigurable intelligent instrument using Labwindows/CVI which has three functions. The orientation of this paper is the design in module level reconfiguration, to lay the foundation for building the reconfigurable automatic test system.

This paper reported the coupling technique of Ag island film-enhanced fluorescence with rare earth co-luminescence effect of Tb–Gd–sodium dodecyl benzene sulfonate (SDBS)–protein system. While the collagen is used as the separator between Ag island film and the fluorophore because it not only can decrease the fluorescence of the blank, but also can promote the adsorption of other proteins and change the conformation of the protein. The effects of Ag island film on both the fluorescence and resonance energy transfer process of Tb–Gd–SDBS–protein system are studied, finding that Ag island film can enhance the energy transfer efficiency of this system, resulting in fluorescence enhancement about tenfold compared with this system without Ag island film. Therefore, this technique is used for the detection of proteins as low as 0.72 ng/mL for BSA and 1.3 ng/mL for HSA. In addition, Ag island film can also change the energy transfer process of Tb–SDBS–protein system.

The anomalous hysteresis in a perovskite solar cell induced by an asymmetric field is confirmed by a capacitance–voltage measurement. By applying several cycles of alternating reverse and forward scans, this hysteresis phenomenon is obviously alleviated, resulting in a hysteresis-less state in the perovskite solar cell. Meanwhile, the open-circuit voltage and power conversion efficiency of the perovskite solar cell are enhanced by 55.74% and 61.30%, respectively, while the current density and fill factor keep almost invariable. The operation of alleviating hysteresis is essential for further research and is likely to bring in performance gains.

To investigate the situation of video-contact and eye diseases for IT industry video operation workers, and to analyze the influencing factors, providing scientific evidence for the make of health-strategy for IT industry video operation workers.We take the random cluster sampling method to choose 190 IT industry video operation workers in a city of Jiangsu province, analyzing the relations between video contact and eye diseases.The daily video contact time of IT industry video operation workers is 6.0-16.0 hours, whose mean value is (I 0.1 ± 1.8) hours. 79.5% of workers in this survey wear myopic lens, 35.8% of workers have a rest during their working, and 14.2% of IT workers use protective products when they feel unwell of their eyes. Following the BUT experiment, 54.7% of IT workers have the normal examine results of hinoculus, while 45.3% have the abnormal results of at least one eye. Simultaneously, 54.7% workers have the normal examine results of hinoculus in the SIT experiment, however, 42.1% workers are abnormal. According to the broad linear model, there are six influencing factors (daily mean time to video, distance between eye and displayer, the frequency of rest, whether to use protective products when they feel unwell of their eyes, the type of dis player and daily time watching TV.) have significant influence on vision, having statistical significance. At the same time, there are also six influencing factors (whether have a rest regularly,sex, the situation of diaphaneity for cornea, the shape of pupil, family history and whether to use protective products when they feel unwell of their eyes.) have significant influence on the results of BUT experiment,having statistical significance. However, there are seven influencing factors (the type of computer, sex, the shape of pupil, the situation of diaphaneity for cornea, the angle between displayer and workers' sight, the type of displayer and the height of operating floor.) have significant influence on the results of SIT experiment,having statistical significance.The health-situation of IT industry video operation workers' eye is not optimistic, most of workers are lack of protection awareness; we need to strengthen propaganda and education according to its influencing factors and to improve the level of medical control and prevention for eye diseases in relevant industries.

We investigate the performances of the near-ultraviolet (about 350 nm–360 nm) light-emitting diodes (LEDs) each with specifically designed irregular sawtooth electron blocking layer (EBL) by using the APSYS simulation program. The internal quantum efficiencies (IQEs), light output powers, carrier concentrations in the quantum wells, energy-band diagrams, and electrostatic fields are analyzed carefully. The results indicate that the LEDs with composition-graded p-Al x Ga1−x N irregular sawtooth EBLs have better performances than their counterparts with stationary component p-AlGaN EBLs. The improvements can be attributed to the improved polarization field in EBL and active region as well as the alleviation of band bending in the EBL/p-AlGaN interface, which results in less electron leakage and better hole injection efficiency, thus reducing efficiency droop and enhancing the radiative recombination rate.

To provide objective data for position and orientation of zygomatic-area implant used in zygo-buccal flange osseointegrated implant obturator for patients with large maxillary defect.Fifty cases of normal unilateral zygomatic body with dentition were measured on three-dimensional spiral CT images. Measurements included the slope angle of zygomatic body on sagittal sectional image, the maximal horizontal distance from the buccal boundary of maxillary alveolar to outboard of maxillary sinus. Furthermore, the configuration of zygomatic body was observed on coronal sectional image.The average rearward slope angle of zygomatic-body was 80.03 degrees. Forty-eight cases showed straight zygomatic-body configurations and two cases quite curvy. The maximal horizontal distance from the buccal boundary of maxillary alveolar to outboard of maxillary sinus was 6.77 mm.In a normal condition, implants can be upright inserted tilting about 10 degrees ahead to utilize much zygomatic bone-volume in high site. In order to improve security and validity of implantation, it is better to take spiral CT examination to evaluate the bone volume and shape of zygomatic body before zygomatic-area implant.

X-ray photoelectron spectroscopy has been used to study band offsets at the n-SnO2/p-GaN hetero-junction. The valence-band offset (�E V) and the conduction-band offset (�E c) are determined to be 0.97 ± 0.2 eV and 0.77 ± 0.2 eV respectively, indicating that the n-SnO2/p-GaN hetero-junction has a type II band alignment.