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• First, the integral terminal sliding surface is used to both eliminate the reaching phase in the sliding mode and ensure a finite-time state error convergence. Meanwhile, two important sliding mode parameters are adaptively adjusted in Lyapunov sense, which eases the complex parameter selection process. • The lumped uncertainty is estimated and compensated by the extreme learning machine (ELM) and thus the switching control component is only needed to handle the effects of the uncertainty estimation error rather than the uncertainty itself. This technique greatly reduces the control chattering and simplifies the selection of the switching gain for practical applications. • The ELM used for the estimation of the lumped uncertainty is regarded as an essential component of the closed-loop control and does not require any training process. Not only can the input weights be randomly chosen as the conventional ELM for pattern classifications, but also the output weights are adaptively adjusted in the sense of Lyapunov to ensure the global stability of the closed-loop control. This is one of the most significant superiorities of the proposed ELM compared to the traditional ELM approaches. In this paper, a novel extreme-learning-machine (ELM)-based robust adaptive integral terminal sliding mode (AITSM) control strategy is developed for the precise tracking control of a steer-by-wire (SBW) system with uncertain dynamics. The proposed control not only ensures the finite-time error convergence but also effectively estimates the lumped uncertainty via a single-hidden layer feedforward network (SLFN) with ELM. Different from conventional ELM using least square optimization approach, the ELM in this work is designed to adaptively estimate the lumped uncertainty from the perspective of global stability of the closed-loop system. The stability of the closed-loop control system is proved in Lyapunov sense. Simulations are carried out to demonstrate the superior control performance of the proposed control. Image, graphical abstract [ABSTRACT FROM AUTHOR]

SrIrO3 (SIO) thin films were epitaxially grown on (001)-oriented 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) single-crystal substrates. Upon applying electric fields to the piezoelectric PMN-PT along the thickness direction, the electronic transport properties of SIO films can be in situ tuned and modulated by non-180° ferroelectric domain rotation-induced strain, piezoelectric strain, and rhombohedral-to-tetragonal structural phase transition-induced strain in the PMN-PT layer, respectively. Moreover, the weak negative magnetoresistance (MR) of the 60-nm SIO films could be modified by applying an electric field to the PMN-PT layer. At T = 2 K, upon the application of E = 4 kV/cm to the PMN-PT, MR at H = 9 T is reduced by 14.2% as compared to that under zero electric field, indicating in-plane compressive strain-induced suppression of the influence of quantum corrections to the conductivity in the SIO film. These results demonstrate that the electric-field controllable lattice strain is a simple approach to get insight into the strain-property relationships of 5d iridate thin films. [ABSTRACT FROM AUTHOR]

The Eu-doped compositionally graded multilayer PbZrO3 antiferroelectric thin films have been deposited on Pt(111)/ Ti/ SiO2/ Si substrates by a sol- gel method. The effect of gradient sequence on microstructure, electrical properties, and energy storage performance has been investigated in detail. X-ray diffraction patterns confirm that both thin films have crystallized into a unique perovskite phase. Down-graded thin films have bigger grain sizes than up-graded films, which is attributed to the influence of the gradient sequence of the thin films layer. The dielectric constant of down-graded films is found to be higher than that of up-graded films. Compared with up-graded thin films, the energy storage density of down-graded films is enhanced due to double hysteresis loop with small hysteresis switch, and high polarization. [ABSTRACT FROM AUTHOR]

Undoped and Eu-doped (1, 3 and 5 mol%) PbZrO3 ( PZ) antiferroelectric ( AFE) thin films have been deposited on Pt (111)/ Ti/SiO2/Si substrates by a sol-gel method. The effect of Eu doping on phase transformation and energy storage performance of PZ thin films have been investigated in detail. It has been seen that on extent of Eu dopant the Curie temperature and electric field-induced phase transformation can be altered. The energy storage properties have been found to be strongly dependent on Eu doping content. With the increase of Eu contents, recoverable energy storage density has been enhanced followed by their subsequent reduction. A maximum energy density (~18.8 J/cm3 at ~900 kV/cm) and minimum energy loss (~7.3 J/cm3) have been achieved on 3 mol% Eu-doped PZ thin films. [ABSTRACT FROM AUTHOR]

This paper introduces a novel dynamical model, building upon the existing dynamical model for Deimos in the current numerical ephemerides, which only encompasses the simple libration effects of Deimos. The study comprehensively incorporates the rotational dynamics of Deimos influenced by the torque exerted by the major celestial bodies (Mars, the Sun) in the solar system within the inertial space. Consequently, a full dynamical model is formulated to account for the complete coupling between the rotation and orbit of Deimos. Simultaneously, employing precision orbit determination methods used for artificial satellites, we develop an adjustment model for fitting data to the complete model. The 12-order Adams–Bashforth–Moulton (ABM) integration algorithm is employed to synchronously integrate the 12 state variables of the full model to obtain the orbit of Deimos.The difference in the orbits obtained by integrating the full model over a period of 10 years and those obtained by the simplified model is at the order of 10 km. After precise orbit determination, this difference decreases to below 100 m, so numerical simulation results indicate that the full dynamical model and adjustment model are stable and reliable. Simultaneously, the integration of the Deimos third-order gravity field in the full model over a 10-year period induces only meter-level positional changes. This suggests that when constructing the complete model, the utilization of a second-order gravity field alone is sufficient. Compared to the simple model, the polar axis of Deimos in the inertial space exhibits a more complex oscillation in the full model. Additionally, the full model calculates that the minimum moment of inertia principal axis of Phobos has an amplitude of approximately 0.5 degrees in the longitude direction and does not exceed 2 degrees in the latitude direction. This work further advances the current dynamical model for Deimos and establishes the foundational model for the generation of a new set of precise numerical ephemerides for Deimos. [ABSTRACT FROM AUTHOR]

Cell fate is precisely modulated by complex but well-tuned molecular signaling networks, whose spatial and temporal dysregulation commonly leads to hazardous diseases. Biomolecular condensates (BCs), as a newly emerging type of biophysical assemblies, decipher the molecular codes bridging molecular behaviors, signaling axes, and clinical prognosis. Particularly, physical traits of BCs play an important role; however, a panoramic view from this perspective toward clinical practices remains lacking. In this review, we describe the most typical five physical traits of BCs, and comprehensively summarize their roles in molecular signaling axes and corresponding major determinants. Moreover, establishing the recent observed contribution of condensate physics on clinical therapeutics, we illustrate next-generation medical strategies by targeting condensate physics. Finally, the challenges and opportunities for future medical development along with the rapid scientific and technological advances are highlighted. [ABSTRACT FROM AUTHOR]

Emergent phenomena such as two-dimensional electron gas (2DEG) and interfacial superconductivity and ferromagnetism are generally built on the interface between insulating oxide thin films and substrates, e.g., LaAlO3/SrTiO3, where the 2D profiles of these electronic states are precisely confined at the interface of two insulators. Herein we report a high-mobility electron gas state with unusual symmetry at the interface of the Sr2CrMoO6/SrTiO3 (110) heterostructures, the fermiology of which follows the cubic crystallographic symmetry rather than the two-dimensional interface itself, resulting in the identical Shubnikov-de Haas oscillations with applied magnetic field along all the twelve equivalent [110] crystallographic directions of SrTiO3, distinctly different from the 2D nature of the electron gas reported previously. Neutron diffraction verifies the predicted ferrimagnetic ordering between Cr and Mo moments. This, together with the magnetic hysteresis loops and negative magnetoresistance in low-field region, suggests possible spin polarization of itinerant electrons. Therefore, a quasi-3D profile, high mobility (up to 104 cm2 V−1 s−1) and possibly spin polarized electronic state is observed in the double-perovskite-based oxide heterostructures. This finding of the electronic properties in Sr2CrMoO6/SrTiO3 (110) heterostructure expands the knowledge of interfacial physics, as well as shines light on oxide-based electronics and spintronics research. The existence of electron gas at the interfaces of oxide-based heterostructures with broken spatial inversion symmetry gives rise to various interesting physical phenomena. Here, the authors report a new type quasi-three-dimensional electron gas state at the interface of ferrimagnetic semiconductor-strontium titanate heterostructures, which show high mobility, high valley degeneracy and possible spin polarization. [ABSTRACT FROM AUTHOR]

Existing Source-Free Domain Adaptation (SFDA) methods typically adopt the feature distribution alignment paradigm via mining auxiliary information (eg., pseudo-labelling, source domain data generation). However, they are largely limited due to that the auxiliary information is usually error-prone whilst lacking effective error-mitigation mechanisms. To overcome this fundamental limitation, in this paper we propose a novel Target Prediction Distribution Searching (TPDS) paradigm. Theoretically, we prove that in case of sufficient small distribution shift, the domain transfer error could be well bounded. To satisfy this condition, we introduce a flow of proxy distributions that facilitates the bridging of typically large distribution shift from the source domain to the target domain. This results in a progressive searching on the geodesic path where adjacent proxy distributions are regularized to have small shift so that the overall errors can be minimized. To account for the sequential correlation between proxy distributions, we develop a new pairwise alignment with category consistency algorithm for minimizing the adaptation errors. Specifically, a manifold geometry guided cross-distribution neighbour search is designed to detect the data pairs supporting the Wasserstein distance based shift measurement. Mutual information maximization is then adopted over these pairs for shift regularization. Extensive experiments on five challenging SFDA benchmarks show that our TPDS achieves new state-of-the-art performance. The code and datasets are available at https://github.com/tntek/TPDS. [ABSTRACT FROM AUTHOR]

Defect engineering constitutes a widely-employed method of adjusting the electronic structure and properties of oxide materials. However, controlling defects at room temperature remains a significant challenge due to the considerable thermal stability of oxide materials. In this work, a facile room-temperature lithium reduction strategy is utilized to implant oxide defects into perovskite BaTiO3 (BTO) nanoparticles to enhance piezocatalytic properties. As a potential application, the piezocatalytic performance of defective BTO is examined. The reaction rate constant increases up to 0.1721 min−1, representing an approximate fourfold enhancement over pristine BTO. The effect of oxygen vacancies on piezocatalytic performance is discussed in detail. This work gives us a deeper understanding of vibration catalysis and provides a promising strategy for designing efficient multi-field catalytic systems in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new strategy to automatically identifies the reaction rules directly from the reaction equation. • A new method named Reaction Rules Topological Matrix Representation (RTMR) to extraction and use of reaction rules. • RTMR can be used to automatically generate reaction networks. • RTMR demonstrates new reactions prediction ability after training with the literature information. In recent years, automatic generation of reaction networks for chemical processes has attracted considerable attention. However, most of the automatic generators focused on the construction of reaction networks by computer and are essentially dependent upon the predefined reaction rules or categories. The reaction rules for constructing reaction networks are derived manually based on the individual's understanding of reaction mechanism equation as well as the corresponding experiences, which hinders the automatic generation of reaction network directly from the complex reaction mechanisms or equations. In this article, we proposed a strategy to automatically identifies the reaction rules directly from the reaction equation using a Reaction Rules Topological Matrix Representation (RTMR) method. Taking the induction period of methanol to olefins (MTO) process as an example, we showed how to use RTMR to extract the information of reaction mechanism equation in the literatures, and then establish the reaction networks of the multiphase catalytic process. The results suggest that RTMR not only provides an effective approach for automatic reaction mechanisms equation extraction, but also demonstrates new reactions prediction ability after training with the literature information. It is expected RTMR can be promisingly implemented in knowledge-driven reaction network generation in multiphase catalytic processes. [ABSTRACT FROM AUTHOR]

Domain adaptation for semantic segmentation is a challenging problem for two reasons. One reason is that annotating labels is an extremely high cost work. Another reason is that the domain gap between the source and target domains limits the performance of semantic segmentation. In this paper, we propose an unsupervised knowledge based domain adaptation method for semantic segmentation. The proposed method consists of three steps. First, the common knowledge is loaded from the source and target domains. Then, the loaded knowledge is filtered according to the specific input image. In the end, the filtered knowledge is fused with the high-level features to guide domain adaptation. Our main contributions are: (1) a first novel knowledge based domain adaptation approach for semantic segmentation and (2) a triangular constraint for knowledge loading, in which the semantic vectors are smoothly imported. Experimental results on three datasets indicate that our method achieves competitive results in some scenarios compared with the state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

In this paper a switched capacitor amplifier-based readout integrated circuit for diode-based infrared sensor is presented. Compared with the conventional integrator-based amplifier, the proposed switched capacitor amplifier achieves the PVT-insensitivity voltage gain. The noise performance is carefully analyzed and optimized, and the simulated total input equivalent noise reaches 8.15 μV within 50 KHz bandwidth. To reduce the power consumption, the two level switch matrix and pulse powered column amplifier are proposed in the design. The methods of dummy metal line and current splitting DAC array are introduced to implement on-chip non-uniformity correction. The chip has been realized with a 0.35 μm 2-poly and 4-metal CMOS technology and occupies an area of 70 mm2 consuming 185 mW from a 5 V power supply. The non-uniformity of output voltage is improved by 78.05% with the help of on-chip non-uniformity correction. [ABSTRACT FROM AUTHOR]

In recent years, significant developments have occurred in the field of optically pumped magnetometers (OPMs), which are widely used in biomagnetic measurements. In this study, we propose a temperature optimization model for a single-beam miniaturized atomic magnetometer. Based on this model, we find that there is an optimal operating temperature for each individual vapor cell, under which the OPM achieves optimal performance. We construct a single-beam zero-field modulation OPM to prove this model. The sensitivity of the magnetometer reaches 18 fT/Hz1/2 (close to the theoretical sensitivity) when we adjust the temperature of the vapor cell through our model, and a detection bandwidth of more than 160 Hz is achieved. It is also discovered that the system bandwidth is reduced when the temperature is increased, whereas the sensitivity of the system does not show notable variation during this process. Our model enables a quick definition of the best working temperature for each individual magnetometer, ensuring the best performance at the lowest operating temperature. This model is especially advantageous for miniaturized OPMs and can also be further applied to arrayed integration for biomagnetic measurement in the future work. [ABSTRACT FROM AUTHOR]

Malignancy-induced ascites is usually low-SAAG ascites.4 However, the SAAG of our case was above 11 g/L. It should be noted that patients with mixed ascites often have high-gradient ascites. Due to a medical history of hepatitis B-related liver cirrhosis and an ascites puncture examination basically conformed to high SAAG, we initially considered this case as cirrhotic ascites. Ascites is the pathological accumulation of fluid in the peritoneal cavity. [Extracted from the article]

Recurrent neural networks (RNNs) are widely used as a memory model for sequence-related problems. Many variants of RNN have been proposed to solve the gradient problems of training RNNs and process long sequences. Although some classical models have been proposed, capturing long-term dependence while responding to short-term changes remains a challenge. To address this problem, we propose a new model named Dual Recurrent Neural Networks (DuRNN). The DuRNN consists of two parts to learn the short-term dependence and progressively learn the long-term dependence. The first part is a recurrent neural network with constrained full recurrent connections to deal with short-term dependence in sequence and generate short-term memory. Another part is a recurrent neural network with independent recurrent connections which helps to learn long-term dependence and generate long-term memory. A selection mechanism is added between two parts to transfer the needed long-term information to the independent neurons. Multiple modules can be stacked to form a multi-layer model for better performance. Our contributions are: 1) a new recurrent model developed based on the divide-and-conquer strategy to learn long and short-term dependence separately, and 2) a selection mechanism to enhance the separating and learning of different temporal scales of dependence. Both theoretical analysis and extensive experiments are conducted to validate the performance of our model. Experimental results indicate that the proposed DuRNN model can handle not only very long sequences (over 5,000 time steps), but also short sequences very well. [ABSTRACT FROM AUTHOR]

Most zero-shot learning (ZSL) methods aim to learn a mapping from visual feature space to semantic feature space or from both visual and semantic feature spaces to a common joint space and align them. However, in these methods the visual and semantic information are not utilized sufficiently and the useless information is not excluded. Moreover, there exists a strong bias problem that the instances from unseen classes always tend to be predicted as some seen classes in most ZSL methods. In this paper, combining the advantages of generative adversarial networks (GANs), a method based on bidirectional projections between the visual and semantic feature spaces is proposed. GANs are used to perform bidirectional generations and alignments between the visual and semantic features. In addition, cycle mapping structure ensures that the important information are kept in the alignments. Furthermore, in order to better solve the bias problem, pseudo-labels are generated for unseen instances and the model is adjusted along with them iteratively. We conduct extensive experiments at traditional ZSL and generalized ZSL settings, respectively. Experiment results confirm that our method achieves the state-of-the-art performances on the popular datasets AWA2, aPY and SUN. [ABSTRACT FROM AUTHOR]

This paper proposes a CMOS front-end readout-integrated circuit (ROIC) with on-chip non-uniformity compensation technique for a diode-based uncooled infrared image sensor. Two techniques are adopted to achieve on-chip non-uniformity compensation: a reference dummy metal line is introduced to alleviate the dominant non-uniformity with IR-drop presented in large pixel array, and a current splitting architecture-based variable current source for diode bias is proposed to compensate other residual non-uniformity. A differential integrator is chosen as the main amplifier of readout circuit for its superior noise performance. For low power design, a pulse-powered row buffer is designed in this work. The proposed ROIC for 384 × 288 diode-based detector array is fabricated with a 0.35- μ m CMOS process. It occupies an area of 4.4 mm × 15 mm, and the power consumption is 180 mW. The measured result shows that with the proposed on-chip non-uniformity compensation, the output voltage variation is greatly reduced from 2.5 V to 60 mV. [ABSTRACT FROM AUTHOR]

In recent small body exploration missions, both landers and orbiters are deployed and operate simultaneously, such as Hayabusa-2, Rosetta mission. With a lightweight transponder on the lander, it is possible to implement tracking session between the lander and the orbiter, which permits to the automatic navigation of the orbiter and could improve the accuracy of the lander position determination. As a testbed, we analyzed the direct range data acquired from CONSERT (Comet Nucleus Sounding Experiment by Radiowave Transmission) experiment between the Philae lander and Rosetta orbiter during the so-called FSS (First Science Sequence) period. With the classical orbit determination method and a high precise Philae lander position(± 2m), pinned from the OSIRIS image, we try to constrain the Rosetta orbit and the GM of comet 67P/Churyumov-Gerasimenko. The work here could supply a reference for future small body exploration with automatic navigation. [ABSTRACT FROM AUTHOR]

China is planning to land a spacecraft on the farside of the Moon, a premiere, by 2018. In essence, the traditional tracking modes, based on direct visibility, cannot operate for the lunar farside lander tracking, and therefore a relay satellite, visible at the same time by both the lander and the Earth, will be required, operating in the so-called four-way mode (Earth-relay satellite-lander-relay satellite-Earth). In this paper, we firstly give the mathematical formulation of the four-way relay tracking mode and of its partial derivatives with respect to the relevant parameters, implemented in our POD software WUDOGS (Wuhan University Deep-space Orbit determination and Gravity recovery System). In a second step, in simulation mode, we apply this relay mode to determining lander coordinates, which are absolutely needed for a sample return mission, or to add constraints on rotation models of the Moon. The results show that with Doppler measurements at a 0.1 mm/s error level, the positioning of the farside lander could be done at centimeters level (1-δ) in the case of a circumlunar relay satellite; and at a 5 meters level (1-δ) in the case of a Lagrange point (L2) Halo relay satellite. [ABSTRACT FROM AUTHOR]

Nowadays, an express/local mode has be studied and applied in the operation of urban rail transit, and it has been proved to be beneficial for the long-distance travel. The optimization of train patterns and timetables is vital in the application of the express/local mode. The former one has been widely discussed in the various existing works, while the study on the timetable optimization is limited. In this study, a timetable optimization model is proposed by minimizing the total passenger waiting time at platforms. Further, a genetic algorithm is used to solve the minimization problems in the model. This study uses the data collected from Guangzhou Metro Line 14 and finds that the total passenger waiting time at platforms is reduced by 9.3%. The results indicate that the proposed model can reduce the passenger waiting time and improve passenger service compared with the traditional timetable. [ABSTRACT FROM AUTHOR]

Understanding the agronomic interventions that ensure higher crop yields and minimize their chances of failure is critical for meeting global nutritional demands. Rice is a staple food crop that is prone to lodging risk, particularly when higher yields are desired. The potential role of a combined application of Zinc (Zn) and Silicon (Si) in determining the grain yield and lodging resistance has been rarely investigated under field conditions. Thus, field trials were carried out to evaluate the grain yield and lodging resistance of rice at two different locations i.e., Qionghai and Wuzhishan, under three levels of Zn (0, 40, and 80 kg ha−1) and Si (0, 120, and 240 kg ha−1). The results showed that Zn application at the rates of 40 and 80 kg ha−1 increased rice yield by 9% and 5% at Qionghai, and by 5% and 6% at Wuzhishan, respectively. The improved grain yield due to Zn application could be attributed to the increased panicles m−2, splikelets m−2, and aboveground biomass. Meanwhile, Zn failed to show any remarkable impact on stem and root lodging susceptibility. Conversely, no significant influence of applying Si on grain yield was observed, while its application at the rates of 120 and 240 kg Si ha−1 enhanced the stem and root lodging resistance (denoted by their respective safety factors, for stem (SFs) and for root (SFr) by 32% and 22% at Qionghai, and by 11% and 34% at Wuzhishan, respectively, compared to zero Si application. The improved lodging resistance in terms of SFs and SFr could be ascribed to the increased stem bending strength and anchorage strength, while self-weight moment of whole plant decreased. In summary, a beneficial role of Si in lodging resistance and Zn in yield enhancement were evidenced in the present study across the two sites. It can be concluded that by combining 40 kg Zn ha−1 with 120 kg Si ha−1, both grain yield and lodging resistance could be simultaneously improved in rice crops. [ABSTRACT FROM AUTHOR]

Novel quantum materials have broad application prospects in spintronic devices and low‐power‐consumption devices. The kagome‐type lattice has special corner‐sharing triangle geometry, providing a rich platform to investigate the relationship of novel correlated topological states, geometry, and strong electron interactions. However, the orbital hybridization in the presence of flat band that originated from the electron localization due to the unique kagome lattice configuration is still unclear. Resonant‐angle‐resolved photoemission spectroscopy is utilized to study the valence band structures of a new vanadium‐based kagome material GdV6Sn6, combined with density functional theory calculation. Herein, a significant hybridization between V 3d and Sn 5p electrons, which paves the way to understand the formation of long‐range magnetic ordering of GdV6Sn6 and other kagome materials at low temperature, is unambiguously revealed in the results. [ABSTRACT FROM AUTHOR]

Source-free domain adaptation requires no access to the source domain training data during unsupervised domain adaption. This is critical for meeting particular data sharing, privacy, and license constraints, whilst raising novel algorithmic challenges. Existing source-free domain adaptation methods rely on either generating pseudo samples/prototypes of source or target domain style, or simply leveraging pseudo-labels (self-training). They suffer from low-quality generated samples/prototypes or noisy pseudo-label target samples. In this work, we address both limitations by introducing a novel Class Prototype Discovery (CPD) method. In contrast to all alternatives, our CPD is established on a set of semantic class prototypes each constructed for representing a specific class. By designing a classification score based prototype learning mechanism, we reformulate the source-free domain adaptation problem to class prototype optimization using all the target domain training data, and without the need for data generation. Then, class prototypes are used to cluster target features to assign them pseudo-labels, which highly complements the conventional self-training strategy. Besides, a prototype regularization is introduced for exploiting well-established distribution alignment based on pseudo-labeled target samples and class prototypes. Along with theoretical analysis, we conduct extensive experiments on three standard benchmarks to validate the performance advantages of our CPD over the state-of-the-art models. • We propose a novel Class Prototype Discovery method for solving the SFDA problem. • A prototype regularization is introduced based on distribution alignment strategy. • CPD outperforms a wide variety of state-of-the-art methods, often by a large margin. [ABSTRACT FROM AUTHOR]

Vortex-induced vibration (VIV) of deck girders frequently drives the wind-resistant design of wind-sensitive bridges from the preliminary to final design stages. Shaping bridge decks is a proven strategy to mitigate VIV. While significant shape modifications are commonly restricted to preliminary design stages, only minor medications are possible at advanced design stages, typically involving adding flow modifiers or changing the shape and location of existing appendages. These mitigation strategies have been implemented in the last decades by carrying out expensive wind tunnel campaigns and following heuristic design rules. This paper proposes an experimental data-driven adaptive surrogate-based optimization approach to systematically identify optimum deck shapes that minimizes the economic cost of the bridge while fulfilling the VIV project specifications. The methodology is conceived to carry out simultaneously the general and detailed shape design of the final deck configuration by harnessing a sequential sampling plan aiming at reducing the sectional model construction costs. The proposed holistic design framework is successfully applied to a real application case involving 26 wind tunnel tests of 1.8-meter wide sectional models to figure out the optimal gap distance and location of maintenance tracks of a twin-box deck equipped with all the appendages included in the final deck design. • A wind tunnel data-driven optimization method for shaping bridge decks is presented. • A Kriging surrogate is sequentially trained with data from 26 sectional model tests. • The gap distance and track position in a twin-box deck were holistically designed. • Vertical and torsional VIV were effectively mitigated, and the cost was minimized. [ABSTRACT FROM AUTHOR]

• We propose a rain streaks removal method in single image based on texture constraint of background scene, which is established by explicitly utilizing the frequency, direction characteristic of rain streaks, and the non-rain texture clues learned from natural images. • Different from adopting an online learning program to provide constraints, we propose a ICA-based fusion method. The ICA allows to learn once for further use, without the need to learn for each rain image. It reduces the computation time. • A new decomposition model is proposed, where a texture constraint for background scene and a low-rank appearance constraint for rain streaks are both utilized to reduce the confusion between image texture and rain structure. Removing rain streaks from single image is mathematically ill-defined and the known strategies tend to over-smooth the background and remove image details. To tackle this problem, this paper proposes a novel two-stage system. Firstly, in view of the frequency and direction of rain streaks, Gabor filter is first used to suppress rain streaks. Based on the bases extracted from natural images, several Gabor filtered images extracted from the input rain image are fused by a new proposed method, and the fused result provides a texture constraint for the non-rain part. Secondly, a low-rank model is adopted to describe rain streaks as they take on similar and repeated patterns in an imaging scene. By combining the texture constraint and the low-rank model, a global cost function is constructed. Finally, an optimization strategy is proposed based on the split Bregman technique, which solves the function with high performance. A large number of experimental results show the competitive performance and efficiency of the proposed method in comparison with the state-of-the-art methods, making it more applicable in real practices. [ABSTRACT FROM AUTHOR]

Stochastic gradient Markov chain Monte Carlo algorithms have received much attention in Bayesian computing for big data problems, but they are only applicable to a small class of problems for which the parameter space has a fixed dimension and the log-posterior density is differentiable with respect to the parameters. This paper proposes an extended stochastic gradient Markov chain Monte Carlo algorithm which, by introducing appropriate latent variables, can be applied to more general large-scale Bayesian computing problems, such as those involving dimension jumping and missing data. Numerical studies show that the proposed algorithm is highly scalable and much more efficient than traditional Markov chain Monte Carlo algorithms. [ABSTRACT FROM AUTHOR]

Background: As an opportunistic pathogen, E. gallinarum mainly leads to nosocomial infections, and it's multi-drug resistance has gained more and more attention. Central nervous system infections caused by E. gallinarum are rare, but have been reported more often in recent years. The previous cases were generally secondary to neurosurgery, especially ventriculoperitoneal shunts. In recent years, the cases largely occurred in patients with impaired immune function. The patient in our report may have had dual risk factors (immune impairment and an invasive surgical procedure).Case Presentation: The patient, a 35-year-old female, was admitted to our hospital for headaches of 3 days duration accompanied by nausea and vomiting for 2 days. The patient had fevers and chills for 3 days before admission; the peak body temperature was 38.5 °C. The patient had a splenectomy in our hospital 2 years earlier for thrombocytopenia and was thought to be immunocompromised. The abnormal findings on physical examination and laboratory testing were as follows: neck stiffness, present; lumbar puncture: pressure, 300 mmH2O; Pandy's test, positive; white blood cell (WBC) count, 1536 × 106/L; monocyte count, 602 × 106/L; monocyte percentage, 39.2%; multinucleate cell count, 934 × 106/L; multinucleate cell percentage, 60.8%; protein, 1.08 g/L; WBC count, 21.1 × 109/ L; neutrophil percentage, 85.3%; neutrophil count, 20.55 × 109/L; C reactive protein (CRP): 136.4 mg/L; procalcitonin, 6.70 ng/mL. The patient was given meropenem (2.0 g, intravenous infusion, every 8 h) for anti-infection supplemented with other symptomatic support treatments. The patient's fever and headache had no significant relief.Conclusions: Central nervous system infections caused by E. gallinarum are rare, but should be suspected, particularly inpatients with impaired immune function or ineffective treatment. Avoiding long-term invasive treatment and improving immunity are helpful to reduce the occurrence of E. gallinarum infections. Early detection and diagnosis, as well as rational antibiotic use, are the keys to achieve satisfactory efficacy. [ABSTRACT FROM AUTHOR]

For the original generative adversarial networks (GANs) model, there are three problems that (1) the generator is not robust to the input random noise; (2) the discriminating ability of discriminator gradually reduces in the later stage of training; and (3) it is difficult to reach at the theoretical Nash equilibrium point in the process of training. To solve the above problems, in this paper, a GANs model with denoising penalty and sample augmentation is proposed. In this model, a denoising constraint is firstly designed as the penalty term of the generator, which minimizes the F-norm between the input noise and the encoding of the image generated by the corresponding perturbed noise, respectively. The generator is forced to learn more robust invariant characteristics. Secondly, we put forward a sample augmentation discriminator to improve the ability of discriminator, which is trained by mixing the generated and real images as training samples. Thirdly, in order to achieve the theoretical optimization as far as possible, our model combines denoising penalty and sample augmentation discriminator. Then, denoising penalty and sample augmentation discriminator are applied to five different GANs models whose loss functions include the original GANs, Hinge and least squares loss. Finally, experimental results on the LSUN and CelebA datasets show that our proposed method can help the baseline models improve the quality of generated images. [ABSTRACT FROM AUTHOR]

The motion of porous particles in fluid flow is of fundamental importance in both natural and industrial processes. Recent work shows that fluid inertia can essentially alter the rotation of spherical porous particles in a simple shear flow. In this contribution, we examined the influence of fluid inertia on the rotation of elliptical porous particles in shear flow by solving the volume-averaged macroscopic equations with a two-dimensional lattice Boltzmann model. It is confirmed that the Darcy number Da has only a minor effect on the rotation of elliptical porous particles if fluid inertia is neglected. At finite fluid inertia, the elliptical porous particles, however, manifested time-periodic rotation with a non-uniform angular rate. For particles with small to intermediate Da, the period of rotation increases with Reynolds number Re up to a critical Rec above which the particle would stop rotating. It is shown that the maximum and minimum angular rates, as well as the inclination angle at which the particle has a minimum angular rate, are significantly affected by Da. A scaling law for the period of rotation initially proposed for solid impermeable particles can be extended to elliptical porous particles at finite fluid inertia. For a highly permeable ellipse, however, Rec has not been observed, and thus, the scaling law breaks down. We calculated the relative viscosity and intrinsic viscosity for simple shear flow containing elliptical porous particles. A formula developed for suspensions with vanishing Re can also be extended to correlate the intrinsic viscosity to Da at finite Re. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel problem that is sentence guided object color change. Based on an original sentence and the corresponding image, by modifying this original sentence, the object color of corresponding image is changed along with the modified target sentence. This problem has two difficulties: (1) How to design a model to learn the change of sentence? (2) How to balance the relationship between the local object and the whole image during learning process? Confronted with these difficulties, as far as we know, few existing methods deal with them effectively. Therefore, we propose a new cascaded model to solve this problem based on generative adversarial networks (GANs). We employ the adversarial game to build a cascaded model, which learns the changed information of a sentence. Then, we specially design a penalty balance term to balance the relationship between local object and entire image in the generated image. Finally, experimental results on the flower and bird datasets demonstrate the validity of the proposed model. [ABSTRACT FROM AUTHOR]

In the original GANs model, there exist two drawbacks for image generation task. On the one hand, a generator cannot deal with a noise that causes an abrupt loss change and inputs of these noises also affect a discriminator, resulting in instability in training process. On the other hand, the discriminator's discriminating ability is limited in the later stage of training. Eventually, generated images are blurred and targets are incomplete. In order to solve the above problems, a GANs model with hybrid augmented discriminator and fake sample penalty is firstly proposed. In this model, we design a hybrid augmented discriminator. We add real and fake samples into this discriminator. These hybrid samples are conducive to improve the discriminating ability of discriminator. Then, to stabilize the training process and achieve local convergence, we add a penalty to the generator on the basis of designed discriminator, which constrains fake samples with ill condition number. Secondly, we validate the generalization of proposed method on three different loss functions including Hinge, GANs and LSGANs loss. Finally, experimental results show that the proposed method is more effective than baseline models. [ABSTRACT FROM AUTHOR]

In view of the significance of non-spherical and permeable particles in liquid-solid and gas-liquid-solid reactors in industrial processes, it is essential to understand and quantify the rheological properties of multiphase flows in these processes. In this study, we investigate the shear viscosity of dilute suspension containing elliptical porous particles at low Reynolds number Re of O (0) by use of a modified lattice Boltzmann model. The fluid flow around and inside an elliptical porous particle is described by the volume-averaged macroscopic governing equations. The relative viscosity is calculated for an elliptical porous particle rotating in a two-dimensional (2D) simple shear flow, based on the relation between the shear stress and the second order moments of non-equilibrium particle distribution function. The effects of porous structure of the elliptical particle on the viscosity and flow field are investigated with different axis ratios in detail. Our results demonstrate that the relative viscosities of dilute suspension containing elliptical porous particles increase linearly with solid volume fraction at various Darcy number for particles with varying axis ratios. Moreover, a simple empirical expression for intrinsic viscosity is proposed as a function of Darcy number. Unlabelled Image • Relative viscosity of multiphase flow increases linearly with Darcy number. • Intrinsic viscosity of suspension decreases monotonously with Darcy number. • A simple empirical formula is proposed to account for the change of intrinsic viscosity. [ABSTRACT FROM AUTHOR]

The successful development and application in industry of methanol-to-olefins (MTO) process brought about an innovative and efficient route for olefin production via non-petrochemical resources and also attracted attention of C1 chemistry and zeolite catalysis. Molecular sieve catalysts with diversified microenvironments embedding unique channel/cavity structure and acid properties, exhibit demonstrable features and advantages in the shape-selective catalysis of MTO. Especially, shape-selective catalysis over 8-MR and cavity-type zeolites with acidic supercage environment and narrow pore opening manifested special host–guest interaction between the zeolite catalyst and guest reactants, intermediates and products. This caused great differences in product distribution, catalyst deactivation and molecular diffusion, revealing the cavity-controlled methanol conversion over 8-MR and cavity-type zeolite catalyst. Furthermore, the dynamic and complicated cross-talk behaviors of catalyst material (coke)-reaction-diffusion over these types of zeolites determines the catalytic performance of the methanol conversion. In this review, we shed light on the cavity-controlled principle in the MTO reaction including cavity-controlled active intermediates formation, cavity-controlled reaction routes with the involvement of these intermediates in the complex reaction network, cavity-controlled catalyst deactivation and cavity-controlled diffusion. All these were exhibited by the MTO reaction performances and product selectivity over 8-MR and cavity-type zeolite catalysts. Advanced strategies inspired by the cavity-controlled principle were developed, providing great promise for the optimization and precise control of MTO process. [ABSTRACT FROM AUTHOR]

Mixed-matrix membranes (MMMs) have arisen as an energy-saving and efficient candidate for CO 2 separation that can mitigate the greenhouse effect. However, challenges still remain in achieving good filler-polymer compatibility and high separation performance. Herein, a mechanochemistry method is proposed to synthesize an amine-functionalized ultramicroporous ZIF-62 (ZIF-UC-6) with good CO 2 affinity. Amino functional groups and open metal sites are introduced into ZIF-UC-6, which significantly improve its CO 2 adsorption capacity of ZIF-62. According to the ideal adsorption solution theory (IAST) calculation, the CO 2 /CH 4 and CO 2 /N 2 selectivity of ZIF-UC-6 is ∼80 and ∼140, respectively. Besides, when ZIF-UC-6 is incorporated into Pebax, hydrogen bonds can form between filler and polymer, which can increase the interfacial compatibility in the MMMs. The optimized membrane possesses a CO 2 permeability of ∼560 barrer, together with high CO 2 /CH 4 and CO 2 /N 2 selectivity of 41.8 and 86.2, surpassing the corresponding upper bounds. Moreover, the prepared MMMs have good pressure resistance and long-term stability. This work demonstrates an effective route for developing MMMs with good interfacial compatibility and high CO 2 separation performance for potential industrial applications. [Display omitted] • Amino groups and open metal sites are introduced simultaneously by mechanochemical method. • The synthesized ultramicroporous ZIF-UC-6 has enhanced CO 2 affinity. • ZIF-UC-6 has improved CO 2 /CH 4 and CO 2 /N 2 ideal selectivity of ∼80 and ∼140, respectivly. • The performance of ZIF-UC-6/Pebax membrane surpasses the corresponding upper bounds. [ABSTRACT FROM AUTHOR]

Background: The magnitude of pulmonary hypertension (PH) is extremely important with respect to the intra‐operative management of children and infants with an isolated ventricular septal defect (VSD). This study aimed to assess the feasibility and accuracy of transesophageal echocardiography for estimating pulmonary arterial systolic pressure (PASP) across isolated VSD. Methods: We compared the results of transesophageal echocardiography vs invasive PASP measured simultaneously. This study included 40 patients (age: 6 months to 6 years; weight: >5 kg) who were undergoing elective surgery for isolated VSDs. Flow signals across the VSDs were identified as high velocity turbulent signals in systole via continuous wave Doppler at 0–120° at the mid‐esophageal level. Peak velocities were recorded. Radial artery systolic pressures were assessed invasively, and PASPs were obtained after exposing the pulmonary artery intra‐operatively. Results: After excluding five patients because of unusable measurements, invasive PASP measurements were obtained in 35 patients (87.5%). There were no significant biases between echocardiographic and catheterization measurements of PASP, with a tight confidence interval measuring, on average, up to 2.6 mmHg. However, the ± 2 standard deviation limits of agreement for mean PASP were −3.8 and 10.6 mmHg. Conclusion: PASP measurements via transesophageal echocardiography in cardiac surgical patients under general anesthesia are recommended for use as a screening and monitoring tool for PH in children and infants, but cannot be used as a diagnostic tool. [ABSTRACT FROM AUTHOR]

Ultrathin and transparent metal films are considered as desirable materials to substitute indium-tin oxide based transparent electrodes. In this work, we report that an Al-doped ZnO layer effectively induced the formation of epitaxial ultrathin and ultrasmooth Au films on mica. The ultrathin Au film shows optimum electrical conductivity, optical properties, and high tolerance to mechanical bending, including a low sheet resistance of 8 Ω/sq and a high average transmittance of 80.1%, and maintains low electric resistivity even after 1000 continuous bending cycles. Moreover, the Au/AZO anode-based organic light-emitting diode was fabricated with the maximum luminance intensity of 32 540 cd/cm2, which demonstrates that it is promising for application in next generation optoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract Image translation is that converting an image from one domain to another domain. Many existing methods with GANs learn a mapping function by adversarial loss and other constraints. However, this learned mapping function can not express the detailed information of generated images and its generalization capability is not enough. To address this problem, in this paper, we propose an unpaired generative adversarial networks model with augmented auxiliary domain. The proposed model combines augmented auxiliary domain with the domains to be learned together to model. In particular, we design multiple generators and discriminators to achieve unpaired cross domain learn. The designed generators and discriminators are subject to multiple adversarial losses and full cycle constraint losses, which can learn the information of augmented auxiliary domain and reduce their mapping space. At last, we conduct experiments on seven cases and the results show that our model has better performance than other unpaired cross domain methods. [ABSTRACT FROM AUTHOR]

Abstract Precise orbit determination and lander positioning are still a challenge for Mars exploration. In this paper, three positioning methods are proposed, including the same-beam differential Very Long Baseline Interferometry (VLBI), four-way orbiter-lander Doppler and three-way loop Doppler for Mars orbiter and lander. Measurement models and these three positioning methods are further analyzed and evaluated using simulation experiments. The results show that about 60-m level accuracy for the Mars lander can be achieved by a combination same-beam differential VLBI data at 10 ps noise level with two-way Doppler data at the 0.1 mm/s noise level. Since VLBI data are sensitive to the angle between two radio sources, the accuracy of the Mars orbiter was not improved. The geometry of four-way orbiter-lander Doppler is more sensitive than the geometry of ordinary two-way Doppler, and therefore, after adding the four-way orbiter-lander Doppler data, the accuracy of the orbiter and lander positioning can reach the meter and decimeter level. Furthermore, the three-way loop Doppler reduces the number of orbital repeater signals and improves the POD accuracy at the meter level as well as the lander positioning accuracy at the decimeter level. Therefore, the three-way loop tracking mode provides an important reference for future Mars missions. Highlights • Three positioning methods for a Mars orbiter and lander are proposed. • Three-way loop Doppler tracking mode reduces the number of orbital repeater signals, transmitting the signal directly from the lander to the ground station. • The POD results of four-way Doppler and three-way loop Doppler data reach the same accuracy level. [ABSTRACT FROM AUTHOR]

The addition of Cd in Al-Cu alloys can trap vacancies and extend their effect on the diffusion of Cu in the Al matrix. Moreover, Cd tends to segregate at the interfaces between θ′ (Al 2 Cu) and α (Al) phases, as well as reduce the interfacial energy and promote the nucleation of the θ′ phase. In the present study, a precipitation hardening model for Al-Cu-Cd alloys was proposed, which considers the effect of Cd on the precipitation process. The model describes precipitation as involving five stages: incubation, nucleation, growth, release of Cd, and coarsening. The effect of vacancies on the diffusion of Cu and on the nature of the dislocation-precipitate interaction was examined. The model incorporating the effect of Cd showed a great difference compared with that not including Cd effects; the predictions of the models were confirmed by experimental results. The influence of the Cu-Cd composition was also analyzed. The results indicate that a decrease in the Cu and Cd content leads to a lower yield strength and a longer duration of the artificial aging stages. [ABSTRACT FROM AUTHOR]

Multi-channel airborne full-waveform LiDAR is widely used for high-precision underwater depth measurement. However, the signal quality of full-waveform data is unstable due to the influence of background light, dark current noise, and the complex transmission process. Therefore, we propose a nonlocal encoder block (NLEB) based on spatial dilated convolution to optimize the feature extraction of adjacent frames. On this basis, a coupled denoising encoder–decoder network is proposed that takes advantage of the echo correlation in deep-water and shallow-water channels. Firstly, full waveforms from different channels are stacked together to form a two-dimensional tensor and input into the proposed network. Then, NLEB is used to extract local and nonlocal features from the 2D tensor. After fusing the features of the two channels, the reconstructed denoised data can be obtained by upsampling with a fully connected layer and deconvolution layer. Based on the measured data set, we constructed a noise–noisier data set, on which several denoising algorithms were compared. The results show that the proposed method improves the stability of denoising by using the inter-channel and multi-frame data correlation. [ABSTRACT FROM AUTHOR]

Spin- and angle-resolved photoemission spectroscopy (SARPES) with high efficiency and resolution plays a crucial role in exploring the fine spin-resolved band structures of quantum materials. Here, we report the performance of the SARPES instrument with a second-generation home-made multichannel very-low-energy-electron-diffraction spin polarimeter. Its energy and angular resolutions achieve 7.2 meV and 0.52°, respectively. We present the results of SARPES measurements of Bi(111) film to demonstrate its performance. Combined with the density functional theory calculations, the spin polarization of the bulk states was confirmed by the spin-layer locking caused by the local inversion asymmetry. The surface states at a binding energy of 0.77 eV are found with 1.0 ± 0.11 spin polarization. Better resolutions and stability compared with the first-generation one provide a good platform to investigate the spin-polarized electronic states in materials. [ABSTRACT FROM AUTHOR]

Mons Gruithuisen is a rare example of nonmare silicic volcanoes on the Moon. We have conducted analyses of the topography, chemical compositions, and subsurface structures of the Gruithuisen region based on remote sensing and gravity data. Our findings include presence of newly detected magma chambers in addition to the previously identified silicic domes in Gruithuisen Region. Our analysis suggests that multiple phases of silicic volcanism have occurred in the Gruithuisen region. The subsurface density revealed by the gravity data also suggests the presence of several low‐density masses in the crust. These early‐formed silicic volcanoes at low elevations are overlain by later‐emplaced mare basalts, however, the side slopes of these volcanoes are not covered by mare basalts, and the low‐FeO abundance material is exposed on the lunar surface. Plain Language Summary: Silicic volcanoes are uncommon on the Moon. We have conducted analyses of the shallow structures and surface features of the Gruithuisen region using remote sensing and gravity data. Our findings reveal the presence of silicic volcanoes that were covered by mare basalt. The topography, chemical composition, and density structure of the lunar crust in the Gruithuisen region suggest the presence of buried silicic volcanoes. The smooth surface units in the region are not ejecta from Imbrium basin, but ancient silicic volcanoes. The surfaces of these silicic volcanoes have been contaminated with mare basalt. Key Points: Buried silicic volcanoes have been identified in the Gruithuisen region on the MoonGravity models reveal the subsurface structures of silicic volcanoesSilicic volcanoes that formed early in the Gruithuisen region were characterized by low elevations and were later covered by mare basalt [ABSTRACT FROM AUTHOR]

Light olefins including ethylene and propylene are important chemical materials, and a diversity of production technologies have been applied in industrial processes. An index called Olefins Production Security Index (OPSI) is proposed for quantifying the performance of techno-economics and security for different olefins production routes. The results show that Coal via Methanol to Olefins (CMTO) and Coal via Methanol to Propylene (CMTP) routes have the higher security rank in terms of raw materials supply and reasonably good economic performance compared with the Nature Gas via Fischer–Tropsch Synthesis to Olefins (NFTO) and Deep Catalytic Cracking (DCC) routes. Carbon Dioxide via Methanol to Olefins (CDMTO) and Carbon Dioxide via Methanol to Propylene (CDMTP) routes have lower carbon dioxide emissions but higher direct production costs. Basically, CMTO, CMTP, and Nature Gas via Methanol to Olefins (NMTO) routes have the top OPSI grades, which means they are more competitive than other routes in terms of security. We also identify the shortcomings of each olefins production route with regard to the security through sensitivity analysis. It is expected the proposed framework plays a role in searching the most suitable production route for light olefins from the viewpoint of security. [Display omitted] • Light olefins production routes are evaluated against techno-economics and security. • Olefins Production Security Index (OPSI) is proposed. • OPSI considers effects of raw materials, energy, technology, economy, and CO 2. • OPSI can be genetically extended to other industrial productions chain. [ABSTRACT FROM AUTHOR]

Summary: Beta‐thalassaemia is an inherited haemoglobin disorder characterised by ineffective erythropoiesis (IE). The detailed pathogenesis of IE remains unclear. In this study, we used single‐cell RNA sequencing (scRNA‐seq) to examine IE in Th3/+ β‐thalassaemic mice. The results showed that the erythroid group was remarkably expanded, and genes involved in biological processes such as iron metabolism, haeme synthesis, protein folding, and response to heat were significantly upregulated from erythroid progenitors to reticulocytes in β‐thalassaemic mice. In particular, we identified a unique cell population close to reticulocytes, named ThReticulocytes, characterised by a high level of heat shock protein 70 (Hsp70) expression and dysregulation of iron metabolism and haeme synthesis signalling. Treatment of β‐thalassaemic mice with the haeme oxygenase inhibitor tin‐mesoporphyrin effectively improved the iron disorder and IE, and the ThReticulocyte population and Hsp70 expression were significantly suppressed. This study revealed in detail the progression of IE at the single‐cell level and possibly provided clues to find therapeutic targets in thalassaemia. [ABSTRACT FROM AUTHOR]

The successful development and application in industry of methanol-to-olefins (MTO) process brought about an innovative and efficient route for olefin production via non-petrochemical resources and also attracted attention of C1 chemistry and zeolite catalysis. Molecular sieve catalysts with diversified microenvironments embedding unique channel/cavity structure and acid properties, exhibit demonstrable features and advantages in the shape-selective catalysis of MTO. Especially, shape-selective catalysis over 8-MR and cavity-type zeolites with acidic supercage environment and narrow pore opening manifested special host–guest interaction between the zeolite catalyst and guest reactants, intermediates and products. This caused great differences in product distribution, catalyst deactivation and molecular diffusion, revealing the cavity-controlled methanol conversion over 8-MR and cavity-type zeolite catalyst. Furthermore, the dynamic and complicated cross-talk behaviors of catalyst material (coke)-reaction-diffusion over these types of zeolites determines the catalytic performance of the methanol conversion. In this review, we shed light on the cavity-controlled principle in the MTO reaction including cavity-controlled active intermediates formation, cavity-controlled reaction routes with the involvement of these intermediates in the complex reaction network, cavity-controlled catalyst deactivation and cavity-controlled diffusion. All these were exhibited by the MTO reaction performances and product selectivity over 8-MR and cavity-type zeolite catalysts. Advanced strategies inspired by the cavity-controlled principle were developed, providing great promise for the optimization and precise control of MTO process. [ABSTRACT FROM AUTHOR]

Polymer gears have long been used on power transmissions with the fundamental durability data, including fatigue S‐N curves, yielding important data informing reliable and compact designs. This paper proposed a prediction method for polyformaldehyde (POM) gear fatigue life based on the innovative WGAN‐XGBoost algorithm. The findings generated herein revealed that the proposed method performs well in terms of prediction accuracy. The predicted fatigue lives, analyzed under different loading conditions, were within 1.5 times dispersion band compared with experimental results. Furthermore, based upon the enhanced fatigue dataset, a thermo‐mechanical coupled prediction formula for POM gear contact fatigue life was proposed. These findings offered a new approach for high‐power density design of polymer gears. Highlights: A prediction method for POM gear fatigue life based on the WGAN‐XGBoost is proposed.A thermo‐mechanical coupled fatigue life prediction formula for POM gears is proposed.The method could shorten the sample size by 25% with the error band within 1.5. [ABSTRACT FROM AUTHOR]

Rate–distortion optimization (RDO) is a crucial technique in block-based hybrid video encoders, which determines the coding option for a certain coding unit to achieve optimal rate–distortion (R–D) performance. However, the current RDO method, which is applied in High Efficiency Video Coding (HEVC), is far from being globally optimal as it ignores the interaction among coding options. In fact, the current coding option not only determines the R–D point of the coded unit but also influences the achievable R–D​ performance of the subsequent coding units due to the spatial–temporal dependencies among the block/frame optimizations. In this paper, we first investigate the R–D characteristics, including operational R–D curves and R–D dependencies, in HEVC through several simulation experiments. It is shown that under the hierarchical fixed QP setting in the HEVC encoder, the temporal R–D dependence dominates the coding process, and the distortion of the reference frame has a strong impact on that of coded frames while less influence on rate. We then introduce distortion effect factors to quantitatively measure the temporal R–D​ dependency. The distortion effect factor at frame level reflects the correlation degree between the current coding frame and the previous coded frames, and the one at block level reflects the influence degree that the distortion of a block to that of subsequent blocks which refer to it in temporal domain. Finally, a pre-encoding based temporal dependent RDO is proposed, which adaptively adjusts quantization parameters and Lagrange multipliers according to the distortion effect factors. Experimental results show that under configurations of low-delay B and P frames, the proposed method can achieve 5.4% and 5.5% bit rate savings on average, respectively, with around 7% encoding complexity increment, compared with the original HEVC encoder. • Rate–distortion optimization is far from being global optimal in video encoders. • Temporal rate–distortion dependency dominates the coding process. • Distortion of reference frame has a strong impact on that of coded frames. • By exploring rate–distortion dependency can improve the coding performance. [ABSTRACT FROM AUTHOR]

The particle rotation was found important in the fluidized bed when the heterogeneous structures appeared. Some researches show that Magnus lift force might play an pivotal role in fluid-solid system, especially when the particles have fast rotation speed. As the Magnus lift force is acted at the single particle level, a pseudo two-dimensional discrete particle model (DPM) was used to investigate the influence of Magnus lift force in fluidized bed. The rotational Reynolds number ( Re r ) bases on the angular velocity and the diameter of the spheres is used to characterize the rotational movement of particles. We studied the influence of Magnus lift force for particles with rotational Reynolds number in the range of 1–100. Our results show that the influence of Magnus lift force is enhanced with a higher Re r . Magnus lift force affects the movement of particles in both radial and axial directions while Re r is high. However, in low Re r case it can be neglected in computational simulation model. This indicates the introduction of Magnus lift force may improve the discrete particle model only in high Re r case and Magnus effect should be considered in real gas-solid two phase system when the particle rotational speed is high. [ABSTRACT FROM AUTHOR]

Single image based rain removal is very challenging due to the lack of temporal and context information, and the existing techniques are usually unpractical in real-time applications as they are time-consuming, and make images blurred in varying degrees. To tackle this issue, this paper proposes a novel framework, based on a new observation that the background has a reasonably low correlation with rain streaks in gradient domain. The framework mainly contains three steps: 1) a rain-free direction with respect to a rain image or a block therein is proposed, describing the fact that there exists a direction along which the image is least-affected in gradient domain; 2) by combing total variation, low-rank constraint and a de-correlation term, a novel decomposition model is proposed to explicitly extract the rain and rain-free gradient components along the direction perpendicular to the just calculated rain-free direction; 3) the rain-free image is reconstructed using Poisson equation, which effectively resists the sparse noise contained in gradients. The favorable performance of the proposed framework has been confirmed by many experimental results, and especially the computational complexity is low. [ABSTRACT FROM AUTHOR]