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• Ghost imaging under low sampling: the proposed method can obtain high quality imaging results with fewer sampling numbers; • Accelerated iteration: the accelerated projected Landweber iteration reduces the number of iterations, improves imaging efficiency; • High quality imaging results: the proposed scheme can extract the joint structures of image, and improve the resolution of imaging results. The realization of high-quality imaging under low sampling is an effective way to solve the practical application of ghost imaging. In this paper, we present an advanced framework of compressed ghost imaging under low sampling. During the imaging process, the regularization and mutual structure filtering operations are performed alternately, which we call mutual structure ghost imaging (MSGI). In the joint filtering of our proposed scheme, the mutual-structural information contained in both the reference image and the target one is applied to enhance the capability of important edge preserving. Thus, high-resolution ghost imaging results can be obtained under low sampling. Moreover, we have adopted a fast-converging iterative format to obtain better imaging results with fewer iterations. Simulation and experimental results show that the proposed method can achieve high-quality imaging results from the random speckle patterns under low sampling and promote the practical process of ghost imaging. [ABSTRACT FROM AUTHOR]

Abstract: A novel nunchaku-like organic second order nonlinear optical chromophore containing a D–π–A backbone and a rigid biphenylene unit was prepared. The UV–vis absorption spectra studies demonstrated that the large rigid structure could suppress dipole–dipole interactions effectively. The electro-optic coefficient of a poled film containing 20% wt of the new dye doped in amorphous polycarbonate afforded a value of 39 pm/V at 1310 nm. Compared with results obtained from a similar D–π–A chromophore without the rigid isolated group, the new dye gave better performance. Moreover, the electro-optic film prepared with the new dye gave greater temporal stability, compared to a similar D–π–A doped poled film that was reported previously. These results indicated that the introduction of a biphenylene group could effectively reduce the intermolecular electrostatic interactions and aid the alignment of the chromophores. [Copyright &y& Elsevier]

Two series of novel electro-optic (EO) polycarbonates incorporating two kinds of tricyanopyrroline-based nonlinear optical (NLO) chromophores were designed and synthesized. These new polycarbonates were prepared through the facile copolymerization of diol NLO chromophores and bisphenol A bis(chloroformate), and the successful preparations were demonstrated by 1H NMR and Fourier transform infrared (FT-IR) spectra. These polycarbonates possessed good thermal stabilities and also showed higher glass transition temperatures (T g) in the range of 156–165 °C. After corona poling, the EO coefficients (r 33) of two poled polycarbonates films were up to 52 pm/V (PC-DTCPC-Ph-2) and 46 pm/V (PC-DTCPC-FPh-2) at the wavelength of 1310 nm. The higher T gs endow the polycarbonates' poled films with good temporal stability of poling-induced dipole alignment, and the resulting poled films of PC-DTCPC-Ph-2 and PC-DTCPC-FPh-2 could retain 95% and 93% of the initial EO activities at 85 °C for more than 500 h respectively. [ABSTRACT FROM AUTHOR]

New energy sources such as solar energy have been developed and utilized due to the shortage of non-renewable energy, and photoelectric materials have attracted more attention, accordingly. Moreover, flexible optoelectronic devices are crucial in the fields of wearable artificial intelligence, portable energy, and smart medical care. At present, photoelectric devices based on traditional perovskite cobalt oxide rigid films have problems such as inability to bend and deformation, which limits their application environment. Here, natural mica with atomically flat surface, high thermal stability, high transparency and good mechanical flexibility was selected as the substrate for preparing a series of LaCoO 3 flexible photoelectric films. These films exhibit excellent photoelectric properties and flexible properties. More importantly, the flexible film still has fast response speed and reproducible light response after 500 bending cycles. It reveals that all-inorganic perovskite LaCoO 3 is a promising candidate for designing high-performance, flexible and wearable optoelectronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Nd:BiVO 4 nanocrystals were synthesized by an effective and simple approach. Nd was incorporated into BiVO 4 host to enhance electronic conductivity and lithium-ion diffusion kinetics, thus promoting the electrochemical performance. When employed as anode materials in lithium-ion batteries, a good cycling stability and high capacity of ~611 mAh g−1 at 100 mA g−1 were delivered. The work can be extensively employed for fabricating other electrode materials and promoting the electrochemical performance in energy storage correlative domains. [ABSTRACT FROM AUTHOR]

The modification and tuning features of nanostructured films are of great interest because of controllable and distinctive inherent properties in these materials. Here, nanocrystalline MoS 2 films were fabricated on the stainless steels by a radio frequency magnetron sputtering at ambient temperature. X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and Raman scattering spectroscopy were used to study the chemical state, chemical composition, crystal structure and vibrational properties of the fabricated MoS 2 films. The bias voltage dependent structural evolution and its influence on the optical properties of MoS 2 nanocrystalline films were systematically investigated. Besides, the residual stresses of MoS 2 nanocrystalline films were explored by employing sin2 ψ approach. X-ray diffraction demonstrates that the nanocrystalline MoS 2 films have single-phase hexagonal crystal structure. All MoS 2 films are polycrystalline in nature. The bandgap values are found to be intensively dependent on bias voltage. Our findings show that the nanocrystalline MoS 2 films with different physical properties and intense quantum confinement effect can be realized through adjusting bias voltages. This work may provide deep insight for realizing transitional metal dichalcogenide-based nanostructured film optoelectronic devices with tunable physical properties through a traditional, very cost-effective, and large-scale fabrication method. [ABSTRACT FROM AUTHOR]

In natural language processing, fact verification is a very challenging task, which requires retrieving multiple evidence sentences from a reliable corpus to verify the authenticity of a claim. Although most of the current deep learning methods use the attention mechanism for fact verification, they have not considered imposing attentional constraints on important related words in the claim and evidence sentences, resulting in inaccurate attention for some irrelevant words. In this paper, we propose a syntactic evidence network (SENet) model which incorporates entity keywords, syntactic information and sentence attention for fact verification. The SENet model extracts entity keywords from claim and evidence sentences, and uses a pre-trained syntactic dependency parser to extract the corresponding syntactic sentence structures and incorporates the extracted syntactic information into the attention mechanism for language-driven word representation. In addition, the sentence attention mechanism is applied to obtain a richer semantic representation. We have conducted experiments on the FEVER and UKP Snopes datasets for performance evaluation. Our SENet model has achieved 78.69% in Label Accuracy and 75.63% in FEVER Score on the FEVER dataset. In addition, our SENet model also has achieved 65.0% in precision and 61.2% in macro F1 on the UKP Snopes dataset. The experimental results have shown that our proposed SENet model has outperformed the baseline models and achieved the state-of-the-art performance for fact verification. • We incorporate the syntactic information into this model. • We use keywords for understanding the key information in the sentence. • The sentence attention can provide a richer semantic representation. [ABSTRACT FROM AUTHOR]

Cobalt-based perovskite-type LaCoO 3 epitaxial films, with different thickness (105, 44, 38 and 11 nm), were epitaxially grown on (100) SrTiO 3 substrates by polymer assisted deposition. LaCoO 3 films have different degree of CoO 6 octahedral distortion, i.e., Jahn-Teller-like tetragonal distortion caused by the biaxially tensile strain. The photoconductivity of the LaCoO 3 epitaxial films under visible light increases gradually with the decrease of film thickness, accompanied by the increasing of CoO 6 octahedral tetragonal distortion. The results reveal that the photoconductive performance of the LaCoO 3 epitaxial films is largely related to the biaxially tensile-strained tetragonal distortion of CoO 6. Higher degree of tetragonal distortion corresponds to smaller value of crystal field splitting energy as well as the band gap, which is beneficial to photoconductivity. • LaCoO 3 epitaxial films show stable visible-light-driven photoconductive performance. • The photoconductivity of the LaCoO 3 epitaxial film can be tuned by epitaxial strain. • Higher CoO 6 tetragonal distortion corresponds to lower Δ CF and narrower E g. [ABSTRACT FROM AUTHOR]

Different La 1-x Ba x MnO 3+δ nanopowders (with x = 0–0.20) were prepared using a traditional sol-gel method. Each sample had a size distribution between 50 and 80 nm with a single perovskite-type structure. The La 1-x Ba x MnO 3+δ based sensors showed excellent gas-sensing performance toward acetone (25–500 ppm) at 300 °C. It was also found that the La 0.80 Ba 0.20 MnO 3+δ sensor exhibited a fast response (≈25 s) and recovery time (≈15 s) in the presence of 100 ppm acetone gas, while the response value of the La 0.80 Ba 0.20 MnO 3+δ sensor to 500 ppm acetone reached 1350%. Moreover, these sensors also had good reproducibility and sensitivity to acetone. It reveals that Ba2+ as doping agent can partially convert Mn3+ to Mn4+, introducing numerous hole carriers into the p-type LaMnO 3+δ semiconductor and increasing the amount of chemisorbed oxygen ions on the surface, which can enhance the response of the sensor toward acetone. Moreover, this doping effect may also increase the hybridization of Mn 3d - O 2p orbits and double exchange interaction existing in the hybrid Mn3+/Mn4+ system, thereby promoting the carriers' conduction rate and gas sensing speed. These results suggest that the La 1-x Ba x MnO 3+δ perovskite-type structures can have large applicability in industrial acetone sensing. [ABSTRACT FROM AUTHOR]

Considering sentiment analysis of microblogs plays an important role in behavior analysis of social media, there has been a significant progress in this area recently. However, most researches are topic-ignored and neglect the sentimental orientation towards different topics. We propose two combined methods for topic-related Chinese message sentiment analysis. One is a graph-based ranking model of LT-IGT which takes both local and global topical information into consideration. And the other is a method of exploring sentimental features on expanded topical words with word embedding which considers both the syntactic and semantic information. These two methods are integrated into a topic-related Chinese message sentiment classifier. Experimental results on SIGHAN8 dataset show the outperformance of this approach compared with other well-known methods on sentiment analysis of topic-related Chinese message. [ABSTRACT FROM AUTHOR]

This paper develops a collaborative representation reconstruction based projections (CRRP) method for dimension reduction. Collaborative representation based classification (CRC) is much faster than sparse representation based classification (SRC) while owning the similar recognition performance to SRC. Both CRC and SRC utilize the class reconstruction error for classification. First, CRRP characterizes the between-class/within-class reconstruction error using collaborative representation; Second, CRRP seeks the projections by maximizing the between-class reconstruction error to the within-class reconstruction error. So the proposed method is called CRRP. The experimental results on AR, Yale B and CMU PIE face databases demonstrate that CRRP is an effective dimension reduction method. [ABSTRACT FROM AUTHOR]

• Ghost imaging of array spatial light field enables physical compression of target. • Real-time ghost imaging with multiple down sampling aliasing information is realized. • The object is successfully obtained from the compressed image by deep learning. Ghost imaging has great application potential in remote sensing observation and biomedical due to the use of a single pixel detector for imaging, which makes it easy to imaging in low light conditions and imperfect spectral regions of the camera. However, the higher the reconstructed image resolution (the more pixels), the larger the number of measurements are required, which makes it difficult to realize the real-time imaging required in the application. Therefore, a new real-time computational ghost imaging method based on deep learning technology and array spatial light field modulation is proposed, which can realize high-quality imaging with high magnification down sampling. Furthermore, the physical compression imaging of objects is realized by adjusting the array light field composed of several identical sub-light fields, and the original image of the object is successfully obtained from the compressed image by deep learning. The resulting compressed image is realized by the physical means of array light field regulation, and allows the far-field transmission of physical compressed image (or use the image compression algorithm for deep compression of the physical compressed image) with low storage data to reduce the transmission data, and then use deep learning to obtain the original image. We implement the proposed method in numerical simulation and real-time imaging experiments of multifold down sampling and physical compressed (eg, 4x, 9x, 16x), and demonstrate its validity and extensibility. This makes the method have a great potential application and prospect in the application scenarios of earth observation imaging and Limited space-time transmission window. [ABSTRACT FROM AUTHOR]