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Quantifying incipient sediment motion in vegetated open channel flow is pivotal for estimating bed load transport and the aquatic ecological environment in rivers. A new formula is developed to predict the critical flow velocity for incipient sediment motion in the presence of emergent vegetation, by incorporating the influence of vegetation drag that characterizes the effects of mean flow and turbulence on sediment movement. The proposed formula is shown to agree with existing experimental data. Moreover, the proposed formula is extended to scenarios with submerged vegetation, suggesting that the vegetation drag may be the inherent impact factor for incipient sediment motion in vegetated open channel flow.

Cobalt-based transition metal phosphides/sulfides have been viewed as promising candidates for supercapacitor (SCs) and hydrogen evolution reaction (HER) featured with their intrinsic merits. Nevertheless, the sluggish reaction kinetics and drastic volume expansion upon electrochemical process hinder their commercial application. In this work, the hollow/porous cobalt sulfide/phosphide based nanocuboids (C-CoP4 and CoS2 HNs) with superior specific surface area are achieved by employing a novel chemical etching-phosphatization/sulfuration strategy. The hollow/porous structure could offer rich active sites and shorten electrons/ions diffusion length. In virtue of their structural advantage, the obtained C-CoP4 and CoS2 HNs perform superior specific capacitance, fast charge/discharge rate and beneficial cycling stability. The advanced asymmetrical supercapacitors assembled by C-CoP4 and CoS2 HNs deliver exceptional energy density, respectively. Furthermore, when employed as hydrogen evolution reaction electrocatalysts, C-CoP4 and CoS2 HNs yield favorable electrocatalytic activity. These findings shed fundamental insight on the design of dual-functional transition metal phosphide/sulfide based materials for optimizing hydrogen evolution reaction and supercapacitor storage properties.

To diagnose the Open-Circuit (OC) fault in the novel fault-tolerant electric drive system, based on d-q-axis current signal, a strong robustness diagnosis strategy is proposed and investigated. Fewer independent power supplies and converters are required in the novel fault-tolerant electric drive system based on Dual-Winding Permanent Magnet Motor (DWPMM), and the system’s reliability, usage ratio and power density have been improved compared to the conventional fault-tolerant motor drive system. However, the novel fault-tolerant electric drive system has the OC fault diagnostic false alarms issue when load changes suddenly or under light-load condition. And it lacks the research on the diagnostic method when the system encounters intermittent OC fault in power switches. By theory derivation, simulation and experimental verification, it can be concluded that the proposed strong robustness OC fault diagnosis strategy based on d-q-axis current signal can overcome the OC fault diagnostic false alarms issue when load changes suddenly or under light-load condition. And it can detect and locate the OC fault of single-phase winding in real time, and diagnose the intermittent OC fault of power switches.

The detrimental lithium (Li) plating is considered as the main cause inducing capacity degradation and safety issue of lithium‐ion battery. This study presents an underlying understanding in detecting, quantifying and revealing mechanism of Li plating on graphite electrode driven by over‐lithiation focused on Li/graphite coin cell by adequate experimental methods assisted with a finite element model. Firstly, Li plating signal is extracted from negative graphite voltage with the distinctive Li stripping plateau converted into increment capacity peak in the subsequent delithiation procedure; Afterwards, in‐situ thermal spectrum with an extra heat peaks corresponding to Li stripping further provides a convincing evidence for Li plating. An intriguing phenomenon is discovered that the presence of Li stripping heat peak will weaken the first delithiation heat peak, which can act as characteristic traits for Li plating diagnostics from the thermal perspective. Subsequently, Coulomb efficiency of Li plating/stripping is calculated to keep below 98.3% over cycling and the decline after 20 cycles implies that capacity loss is ascribed to the aggravated irreversible Li plating. Next, with the complement of post‐mortem approaches represented by 7Li NMR (Nuclear magnetic resonance), Li plating is semi-quantified to unveil Li plating/stripping mechanism over cycling. Finally, a 2D electrochemical model is presented for this Li/graphite cell to further unravel Li plating. Results shows that the lowest graphite voltage, as well as the highest Li plating current density and thickness of plated Li always occurs at the graphite/separator interface. The results can also provide guidance for full/commercial cell.

As the key piece of equipment of a micro-irrigation system, the filter can prevent clogging of the emitter and ensure normal operation of the micro-irrigation system. A gill-piece separation device is used for the removal of viscous sediment, which helps to reduce the sediment concentration and decrease the burden on the filter. In this study, using the water–sediment separation efficiency as an evaluation index, a uniform orthogonal experiment was conducted to study the flow rate, sediment concentration, and gill-piece spacing using a physical model. Based on the experimental results of the physical model, multiple linear regression and projection pursuit regression were used for analysis. The results showed that the order of the factors affecting the water–sediment separation efficiency was as follows: flow rate at muddy water inlet > gill-piece spacing > sediment concentration. The correlation coefficients of the water–sediment separation efficiency models established using multiple linear regression and projection pursuit regression were 0.93 and 0.98, respectively. Both models could predict the water–sediment separation efficiency and determine the optimal working conditions of the gill-piece separation device. HIGHLIGHTS A prediction model for water–sediment separation efficiency of the gill-piece separation device was established under the conditions of sediment concentration of 2–12 kg/m3, flow rate of 0.3–1.1 m3/h, and gill-piece spacing of 5–11 cm.; The order of influence of each factor on the water–sediment separation efficiency is as follows: flow rate at muddy water inlet > gill-piece spacing > sediment concentration.

Photothermal catalysis is a widely researched field in which the reaction mechanism is usually investigated based on the photochemical behavior of the catalytic material. Considering that the adsorption of reactants is essential for catalytic reactions to occur, in this study, the synergistic effect of photothermal catalysis is innovatively elucidated in terms of the electron transfer behavior of reactant adsorption. For the H2 + O2 or CO + H2 reaction systems over a ZnO catalyst, UV irradiation at 25 °C or heat without UV irradiation did not cause H2 oxidation or CO reduction; only photothermal conditions (100 or 150 °C + UV light) initiated the two reactions. This result is related to the electron transfer behavior associated with the adsorption of CO or H2 on ZnO, in which H2 or CO that lost an electron could be oxidized by O2 or hydroxyls. However, the electron-accepting CO could be reduced by the electron-donating H2 into CH4 under photothermal conditions. Based on the in-situ characterization and theoretical calculation results, it was established that the synergistic effect of the photothermal conditions acted on the (002) crystal surface of ZnO to stimulate the growth of zinc vacancies, which resulted in the formation of defect energy levels, adsorption sites, and an adjusted Fermi level. As a result, the electron transfer behavior between adsorbed CO or H2 and the crystal surface varied, which further affected the photocatalytic behavior. The results show that the effect of photothermal synergy may not only produce the expected kinetic energy, but more importantly, produce energy that can change the activation mode of the reactant gas. This study provides a new understanding of the CO catalytic oxidation and reduction processes over semiconductor materials.

The general rules of rotor pole and armature winding configurations combinations for 24-slot stator wound field flux switching machines (SWFFSMs) are investigated thoroughly in this article. Meanwhile, based on the virtual coil method, a novel general auxiliary evaluation variable, which is proportional to the fundamental amplitude of open-circuit flux-linkage of armature coil is proposed in this article. Hence, these SWFFSMs with larger open-circuit flux-linkage and back-EMF can be obtained effectively. In addition, the effect of rotor poles on the complementarity of armature windings is analyzed so that more sinusoidal and symmetrical back-EMF can be acquired. Furthermore, for these SWFFSMs with larger open-circuit back-EMF, the torque capability is restricted to a considerable extent due to the deep magnetic saturation caused by overlapping armature winding. Hence, a new method by optimizing the ratio of armature slot area and excitation slot area is proposed in this article to ensure that the higher torque density of selected SWFFSMs can be maintained. To verify the validity of analysis and methodology proposed in this article, seven representative SWFFSMs are chosen for verification at no load by the finite-element analysis (FEA) while a 24s/17p SWFFSM with the highest torque density is chosen for further verification at on-load conditions by the FEA and experiments.

Delay/Disruption Tolerant Networking offers a solution to communications in challenged networks despite the long propagation delay, and intermittent connectivity is commonly characteristic of deep-space communications. It combined with the actual application scenarios of M/G/1 queuing model and based on the data delivery mechanism of store-and-forward and retransmission under Bundle Protocol/Licklider Transmission Protocol in DTN. The data delivery time can be divided into two parts by the last round of LTP data segments transmission process, the custody queue length model of BP data unit (i.e. bundle) in relay nodes memory space is determined by calculating the retransmission time of LTP data segments spent in different delivery parts, which can directly measure the consumption and use of relay nodes memory resources. Without affecting the correct delivery of data and in order to obtain a more perfect memory resources allocation strategy, the optimized length of LTP data segment and the optimized number of bundles aggregated by per LTP block are proposed as the joint optimization scheme. The simulation results show that in deep-space channel environment where bundle arrival rate and bit error rate constantly change, the joint optimization scheme proposed in this paper can always maintain the shortest average queue length, which means, occupy less memory space. Compared with the queue without optimization, the queue length of the joint optimization scheme is reduced by 76.65%, which demonstrates the superior performance of this scheme, and realizes the reasonable optimization and utilization of the memory resources of the relay nodes in DTN.

Grasping unfamiliar objects (unknown during training) based on limited prior knowledge is a challenging task in robotic manipulation. Recent solutions typically require predefined information of target objects, task-specific training data, or a huge experience data with training time-consuming to achieve usable generalization ability. This paper introduces a robotic grasping strategy based on the model-free deep reinforcement learning, named Deep Reinforcement Grasp Policy. The developed system demands minimal training time and limited simple objects in simulation and generalizes efficiently on novel objects in real-world scenario. Without requiring any type of prior object awareness or task-specific training data. Our scalable visual grasping system is entirely self-learning approach. The model trains end-to-end policies (from only visual observations to decisions-making) to seek optimal grasp strategy. A perception network utilizes a convolutional neural network that maps visual observations to grasp action as dense pixel-wise Q-values represent the location and orientation of a primitive action executed by a robot. In simulation and physical experiments, a six-DOF robot manipulator with a two-finger gripper is utilized to validate the developed method. The empirical results demonstrated successfully based only on minimal previous knowledge of a few hours of simulated training and simple objects.

Recent advances in molecular biology have led to the CRISPR revolution, but the lack of an efficient and safe delivery system into cells and tissues continues to hinder clinical translation of CRISPR approaches. Polymeric vectors offer an attractive alternative to viruses as delivery vectors due to their large packaging capacity and safety profile. In this paper, we have demonstrated the potential use of a highly branched poly(β-amino ester) polymer, HPAE-EB, to enable genomic editing via CRISPRCas9-targeted genomic excision of exon 80 in the COL7A1 gene, through a dual-guide RNA sequence system. The biophysical properties of HPAE-EB were screened in a human embryonic 293 cell line (HEK293), to elucidate optimal conditions for efficient and cytocompatible delivery of a DNA construct encoding Cas9 along with two RNA guides, obtaining 15–20% target genomic excision. When translated to human recessive dystrophic epidermolysis bullosa (RDEB) keratinocytes, transfection efficiency and targeted genomic excision dropped. However, upon delivery of CRISPR–Cas9 as a ribonucleoprotein complex, targeted genomic deletion of exon 80 was increased to over 40%. Our study provides renewed perspective for the further development of polymer delivery systems for application in the gene editing field in general, and specifically for the treatment of RDEB.

The effect of thermal aging at 475 °C and 750 °C of Z3CN20.09M cast duplex stainless steel (CDSS) on microstructure, mechanical and intergranular corrosion properties were investigated by transmission electron microscope (TEM), nano indenter, scanning electron microscope (SEM) and corrosion fatigue test system. The result indicated that the spinodal decomposition and G precipitated were occurred after aged at 475 °C, as well as sigma precipitated at 750 °C. The microstructure degeneration of ferrite was saturated after aged for 2000h and 200 h at 475 °C and 750 °C respectively. The mechanical properties, intergranular corrosion resistance and corrosion fatigue lives were continuing deteriorated with increasing the aging time at both temperatures. The difference of the degeneration mechanisms of Z3CN20.09M CDSS aged at 475 °C and 750 °C was analyzed.

In this study, Mn catalysts have been designed based on manganese oxide octahedral molecular sieve (OMS-2) supports to optimize the catalytic activity in the degradation of organic pollutants. Herein, two different synthetic strategies: Pre-incorporation vs. wet-impregnation have been employed to synthesize [PW]-OMS-2 and [PW]/OMS-2. For [PW]-OMS-2, energy dispersive X-ray spectroscopy (EDX) confirmed that dispersed granular phosphotungstic acid attached and located at the surface of OMS-2, meanwhile some W atoms have been doped into frameworks of OMS-2. However, for [PW]/OMS-2, the W atoms cannot enter the OMS-2 frameworks. A correlation has been established between the different synthetic strategies and catalytic activities. The [PW]-OMS-2 is the most highly effective and stable over than [PW]/OMS-2 and OMS-2 itself for the organic pollutants removal. This may be caused not only by the synergetic effect of [PW] and OMS-2, but also by doping W into frameworks of OMS-2. Therefore, this work provides a new environmentally-friendly and heterogeneous PMS activator and it may be put into practice to degrade organic pollutants.

Low latency stream processing on large clusters consisting of hundreds to thousands of servers is an increasingly important challenge. A crucial barrier to tackling this challenge is stragglers , i.e., tasks that are significantly straggling behind others in processing the stream data. However, prior straggler mitigation solutions have significant limitations. They balance streaming workloads among tasks but may incur imbalanced backlogs when the workloads exhibit variance, causing stragglers as well. Fortunately, we observe that carefully scheduling the outgoing tuples of different tasks can yield benefits for balancing backlogs, and thus avoids stragglers. To this end, we present Hone , a tuple scheduler that aims to minimize the maximum queue backlog of all tasks over time. Hone leverages an online Largest-Backlog-First ( LBF ) algorithm with a provable good competitive ratio to perform efficient tuple scheduling. We have implemented Hone based on Apache Storm and evaluated it extensively via both simulations and testbed experiments. Our results show that under the same workload balancing strategy– shuffle grouping , Hone outperforms the original Storm significantly, with the end-to-end tuple processing latency reduced by 78.7 percent on average.

We investigate the problem of time-of-arrival (TOA) based localization under possible non-line-of-sight (NLOS) propagation conditions. To robustify the squared-range-based location estimator, we follow the maximum correntropy criterion, essentially the Welsch $M$-estimator with a redescending influence function which behaves like $\ell_0$-minimization towards the grossly biased measurements, to derive the formulation. The half-quadratic technique is then applied to settle the resulting optimization problem in an alternating maximization (AM) manner. By construction, the major computational challenge at each AM iteration boils down to handling an easily solvable generalized trust region subproblem. It is worth noting that the implementation of our localization method requires nothing but merely the TOA-based range measurements and sensor positions as prior information. Simulation and experimental results demonstrate the competence of the presented scheme in outperforming several state-of-the-art approaches in terms of positioning accuracy, especially in scenarios where the percentage of NLOS paths is not large enough., Comment: Published in CSSP

In real-time systems, where tasks have timing requirements, once the workload exceeds the system’s capacity, missed due dates may cause system overload. In this situation, finding an optimal scheduling that minimizes the cumulative values of late tasks is critical in both theory and practice. Recently, formalizing scheduling problems as a class of generalized problems, such as Satisfiability Modulo Theory (SMT) and Maximum Satisfiability (MaxSAT), has been receiving immense concern. Enlightened by the high efficiency of these satisfiability-based methods, this paper formulates the single-machine scheduling problem of minimizing the total weight of late tasks as a Weighted Partial Maximum (WPM) Satisfiability problem. In the formulation, scheduling features are encoded as rigidly enforced hard clauses and the scheduling objective is treated as a set of weighted soft ones. Then an off-the-shelf WPM solver is exploited to maximize the total weight of the satisfied soft clauses, provided that all the hard clauses are satisfied. Experimental results demonstrate that, compared with the existing satisfiability-based methods, the proposed method significantly improves the efficiency of identifying the optimal schedule. Moreover, we make minor changes to apply the WPM formulation to parallel-machine scheduling, showing that the proposed method is sufficiently flexible and well scalable.

In this paper, we analyze how sequentially introducing decision variables into an integer program (IP) affects the value function and its level sets. We use a Gilmore-Gomory approach to find parametrized IP value functions over a restricted set of variables. We introduce the notion of maximal connected subsets of level sets - volumes in which changes to the constraint right-hand side have no effect on the value function - and relate these structures to IP value functions and optimal solutions.

This paper investigates the design and analysis of a robust nonlinear controller for voltage source converters (VSCs) connected to weak AC grids. Feedback linearization method is used to develop the control inputs that regulate the active power and output voltage of the grid-connected converter. The frequency-domain model of an LCL filter in $dq$ -frame is used to develop the nonlinear control blocks for small-signal stability analysis. Impact of phase-locked loop (PLL) is added to the control block through feedforward loops. It is shown that unlike vector controlled converters, the proposed controller is not negatively affected by the PLL gains and a broader range of operation is achieved. In addition, the designed controller is robust against sudden active power commands from 0 to 1 p.u., and is capable of fault ride through when AC grid is very weak. The robustness of the proposed controller is evaluated using eigenvalue analysis of the linearized closed-loop model and time-domain simulations of a grid-connected VSC in various cases.

The crustacean stomatogastric ganglion (STG) is a valuable model for understanding circuit dynamics in neuroscience as it contains a small number of neurons, all easily distinguishable and most of which contribute to two complementary feeding-related neural circuits. These circuits are modulated by numerous neuropeptides, with many gaining access to the STG as hemolymph-transported hormones. Previous work characterized neuropeptides in the hemolymph of the crab Cancer borealis but was limited by low peptide abundance in the presence of a complex biological matrix and the propensity for rapid peptide degradation. To improve their detection, a data independent acquisition (DIA) mass spectrometry (MS) method was implemented. This approach improved the number of neuropeptides detected by approximately two-fold and showed greater reproducibility between experimental and biological replicates. This method was then used to profile neuropeptides at different stages of the feeding process, including hemolymph from crabs that were unfed, or 0 min-, 15 min-, 1 hour-, and 2 hours post-feeding. The results show differences both in the presence and relative abundance of neuropeptides at the various time points. Additionally, 96 putative neuropeptide sequences were identified with de novo sequencing, indicating there may be more key modulators within this system than is currently known. These results suggest that a distinct cohort of neuropeptides provides modulation to the STG at different times in the feeding process, providing groundwork for targeted follow-up electrophysiological studies to better understand the functional role of circulating hormones in the neural basis of feeding behavior.

Person re-identification (reID) aims at finding the same person in different camera views. In real-world scenarios, it is quite often that the suspect’s appearance is not known while the suspect’s escape route is known. This paper introduces a new person reID setting, where the query includes both the real suspect’s trajectory and several possible suspects. The goal is to identify the actual suspect and retrieve images of the real suspect. Prior work focuses on extracting pedestrians’ discriminative visual features or using spatial-temporal information while neglecting the importance of cross-camera trajectory information. Due to the spatial-temporal consistency, the trajectory and image complement each other and the trajectory is associated with the image data. Therefore, we consider retrieving the suspect’s image based on the trajectory and introducing a Hidden Markov Model based trajectory framework to jointly analyze image data and trajectory information. We evaluate our methods on two datasets containing person images and trajectory information, demonstrating our approach’s effectiveness.

Service function chain (SFC) has been recognized as one of the most important technologies that can satisfy dynamic service demands in the edge clouds. However, how to efficiently embed SFCs in the dynamic edge-cloud scenarios remains as a challenging problem. Considering different network topologies, we devise two deep reinforcement learning (DRL)-based methods for two network sizes: a deep deterministic policy gradient (DDPG) based method for the small-scale networks and an asynchronous advantage actor-critic (A3C) based approach for the large-scale networks. Simulation results demonstrate that our proposals can efficiently deal with the SFC-DMP in edge clouds and outperform the state-of-the-art methods in terms of the delay.

Data-parallel applications generate a mix of coflows with and without deadlines. Deadline coflows are mission-critical and must be completed within deadlines, while the non-deadline coflows desire to be completed as soon as possible. Scheduling such mix-coflows is an important problem in modern datacenters. However, existing solutions only focus on one of the two types of coflows: they either solely concentrate on meeting the deadlines of deadline-aware coflows or reducing the coflow completion times (CCTs) of non-deadline coflows. In this article, we study the problem of optimizing deadline and non-deadline coflows simultaneously. To this end, we present a new optimization framework, mixCoflow , to schedule deadline coflows to minimize and balance their bandwidth footprint, such that non-deadline coflows can be scheduled as early as possible. Specifically, we develop the mathematical model and formulate the scheduling problem for deadline coflows as a lexicographical min-max integer linear programming (ILP) problem. Through rigorous theoretical analysis, this ILP problem has been proved to be equivalent to a linear programming (LP) problem that can be solved with standard LP solvers. By solving this LP, mixCoflow is able to balance the bandwidth footprint of deadline coflows while guaranteeing their deadlines. As a result, non-deadline coflows can be scheduled as soon as possible whenever they arrive. To demonstrate the effectiveness of our work, we have conducted extensive simulations based on a widely used Facebook data trace. The simulation results verify that mixCoflow can achieve significant improvement on the average CCT of non-deadline coflows, at no expense of increasing the deadline miss rates of deadline coflows, when compared to the state-of-art solutions.

Mixed halide perovskites with the ability to tune bandgaps exhibit attractive applications in tandem solar cells, building integrated photovoltaic and wavelength-tunable light-emitting devices. However, halide demixing under illumination or in the dark with a charge-carrier injection in both hybrid and inorganic perovskites results in bandgap instability and current-density-voltage (J-V) hysteresis, which can significantly hamper their application. Here, we demonstrate that halide segregation and J-V hysteresis in mixed halide inorganic CsPbIBr2 solar cells can be effectively mitigated by introducing an intermediate phase-enhanced Ostwald ripening through the control of the chemical composition in the CsPbIBr2 precursor solution. Excess amounts of either PbBr2 or CsI are incorporated into originally even molar amounts of PbBr2 and CsI precursor solutions. With the PbBr2-excess, we observed an enlarged perovskite grain size, no detectable halide phase segregation at the grain boundaries nor the perovskite/TiO2 interface, an increased minority carrier lifetime, a reduced J-V hysteresis, and an improved solar-cell performance. However, different CsI:PbBr2 stoichiometric ratios were found to have different effects on the performance of the perovskite solar cell. The excessive lead phase is reactive with the dimethyl sulfoxide (DMSO) in the precursor solution to form the Pb(I, Br)2-DMSO complex and the quasi-two-dimensional (2D) CsPb2(I, Br)5, which are conducive to Ostwald maturation and defect extinction. Finally, the CsPbIBr2 solar cell with a PbBr2-excess precursor composition reaches a power conversion efficiency (PCE) of 9.37% (stabilized PCE of 8.48%) and a maximum external quantum efficiency of over 90%.

In this study, a single-channel supersonic cascade model is investigated experimentally at a freestream Mach number of 2.4 to obtain a better understanding of the flow field evolution during the throttling process. A flap is placed at the channel exit to choke the flow linearly. Measurements include 1-kHz schlieren imaging and 10-kHz simultaneous fast-response wall pressure. Three stages, namely attached flow, separated flow, and oscillatory flow, are identified in the throttling process. The joint time–frequency analysis and wall pressure spectrum contour exhibit the time evolution and spatial distribution of the pressure fluctuation. With the increase in backpressure, the pressure fluctuation in the low-frequency shock oscillation range of 40–400 Hz on the suction surface located in the separated flow gradually enhances. The power spectral, coherence, and phase analyses of the schlieren images describe the dominant oscillation structure and its relationship with other regions. During the separated flow, the pressure change in the subsonic separated region first lead to a change in the state of the separated shear layer, after which the shock waves in the shock train, move. The oscillatory flow is a process wherein the upstream shock wave oscillates, causing the entire downstream channel to fluctuate.

The nacre-inspired Al-Si/TiB2 composites were successfully prepared by freeze casting and pressure infiltration. The microstructures and mechanical properties of nacre-inspired Al-Si/TiB2 composites were studied by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and mechanical testing. The results show that the high performance of Al-Si/TiB2 composites can be attributed to the clean interfaces between TiB2 and Al and several toughening mechanisms, such as crack blunting, crack branching, crack deflection, plastic deformation of Al layer, and bridging of the uncracked fracture process zone. Specifically, the compressive strength, three-point bending strength and KIC of composites corresponding to LS were 640–710 MPa, 629 MPa, and 16.4 MPa m1/2, respectively. The fracture behaviors of the Al-Si/TiB2 composites have been discussed in detail in this work. It was found that single cracks were accompanied by the propagation of multiple micro-cracks in the layered composites. The precipitation of Si particles at the TiB2/α-Al interface and the Al phases infiltrated in the TiB2 layers play a great role in the formation of single crack fractures and multiple micro-cracks fractures, respectively, in the nacre-inspired Al-Si/TiB2 composites.

Purpose Leading-edge information and communication technology provides the base to facilitate obtaining, interoperating and federating shared metadata knowledge in collaborative networks from multiple heterogeneous data sources. The purpose of this study is to develop a methodology and a set of mechanisms to support this task in the collaborative environment. Design/methodology/approach In this paper, the authors first identify and capture four main typical sources to find or generate metadata knowledge for shared data in emerging networked environments, including existing well-designed metadata, the typical ones are relational schemas of existing databases in the environment; fragmented metadata sources, i.e. metadata that can be realized from existing mission statements and example application scenarios in the environment, usually characterized by their fragmented, lightweight and behavior-intensive features; extracting metadata for simple labeled unstructured data, e.g. textual communications among its stakeholders; and semantic constraints on metadata, e.g. the temporal data behavior could be generated from governance policies in the environment. Second, the authors introduce their systematic methodology to the unification of the resulted metadata consisting of four semiautomated unification steps that gradually develops and enhances a unified ontology for the environment, formalized in web ontology language. Findings The methodology steps and their corresponding mechanisms are described and exemplified in detail in this paper. Furthermore, this paper presents the outcome of applying the authors’ methodology to an example emerging case through the generation of a unified ontology for that environment. Originality/value The addressed example application area is a real case in the field of higher education in China and therefore serves as a proof of concept and verification of the effectiveness of the authors’ proposed approach.

Several techniques (such as scanning electron microscopy (SEM) and gas adsorption systems) have been used to study the pore features and structures of shale reservoirs. The available methods and techniques have restricted the specific research on micropores, and the morphology, genesis, volume, and main factors controlling pore characteristics are yet to be analyzed. Currently, there is no systematic understanding of the role that these spaces play in gas storage and flow. As such, our understanding of the spatial connectivity of pores and reserves of shale reservoirs is limited. In this study, the pores of the Fuling shale gas reservoir in the Sichuan Basin were systematically observed by SEM and transmission electron microscopy. Images of pores smaller than 2 nm were captured for the first time, and their morphology and genesis were analyzed by combining these images with the rock mineralogy theory. The pore size distribution characteristics of the reservoir were analyzed by the adsorption-mercury injection method and nuclear magnetic resonance, and the main factors controlling the distribution of different pore sizes were analyzed. The results show that large numbers of micropores were distributed between the mesopores and macropores in the shale reservoir, which mainly consisted intergranular pores, intermolecular pores, interlamellar pores of clay minerals, and organic matter skeleton pores. The development of pores smaller than 1 nm was mainly controlled by the clay mineral content, and the development of pores with a size of approximately 1-2 nm was related to the contents of clay minerals and organic matter. These pores could connect the macropores and mesopores well, which is important for gas storage and flow. In this paper, the types, distribution, and main controlling factors of micropores were studied, and our understanding of the reservoir space was improved from the nanometer level to the Angstrom level, which is important for gas storage and flow process analysis.

In longwall mining, the deformation and destruction of overlying strata always lag behind coal extraction. The overlying strata characteristics at the lateral boundary of the stope can be classified into four categories, i.e., Hard-Soft, Soft-Hard, Hard-Hard, and Soft-Soft. In order to analyze the effect of the above four structures, we adopt viscoelastic theory to the finite element method (FEM) and define the point safety factor to evaluate the rock damage. The accuracy of programming is verified through example verification. A modified viscoelastic-plastic FEM model is applied to analyze the performance of four overburden structures. The numerical computation results show the following: From the rupture of overburden rock to its stabilization, the duration time of four typical structures can be sorted as “Soft-Soft

The moving-coil type voice coil motor (VCM) has very light moving mass, which can achieve higher reciprocating frequency and work efficiency. However, the power supply lead connected to the moving coil can be easily broken under long-term reciprocating motion, so it is rarely used in compressor drive systems. The core technology of the compressor development trend is a driving motor with high-efficiency, high reciprocating frequency, certain piston stroke, and light moving mass. Due to its structural characteristics, the moving-coil type VCM has broad application prospects. This article proposes a new structure for power supply of a moving coil VCM based on the principle of electromagnetic induction. The proposed VCM can overcome the problems of aging and disconnection of power supply lines caused by reciprocating motion, and meet the requirements of high-frequency and long-term repetitive action of the moving coil. The content of this article is as follows. First, the construction of the proposed VCM is introduced. Second, the power-driven circuit based on interleaving double switch forward converter is provided. Finally, two working modes of drive circuit for reciprocating motion are proposed. Simulation and experimental results verify the effectiveness of the method.

The throttling process in a supersonic cascade is investigated in a free-jet wind tunnel at Mach 2.4. High-speed schlieren imaging and high-resonance frequency pressure measurements are used to capture the flow features. A flap is placed at the channel exit to choke the flow linearly. In the throttling process before the onset of oscillatory flow, the shock train leading shock leads to large area of flow separation near the suction surface and high total pressure loss. The oscillatory flow is triggered by the expansion of the flow separation induced by the impingement of the shock train leading shock onto the suction surface, which belongs to the Dailey criterion. The alarm is triggered during oscillatory flow detection, based on the pressure data at the optimal S5 transducer, either before the large-amplitude pressure fluctuation begins or after it ends. Comparing with other algorithms, the derivative-based algorithm has no data to be stored and no expensive calculation is the best technique for detection. To adjust the alarm margin, three detection points are set upstream of the S5 transducer and detection is performed based on the schlieren images. All algorithms detect the sudden drop in light intensity caused by the arrival of the shock train leading shock at the detection location. The alarm margin is the largest at point C, which is farthest from the suction surface tip, and smallest at point A, which is closest to the suction surface tip.

The traditional direct toque control (TDTC) for induction motors (IM) is afflicted by large torque ripple, high current total harmonic distortion (THD), and variable switching frequency. Recently, some improved direct torque control (DTC) methods have been proposed to address the above problems, but they often suffer from obscure concept, intensive computation, and poor robustness. To further improve the performance, this article proposes a DTC method based on minimum voltage vector (VV) error. The proposed strategy effectively optimizes the duty ratio of fundamental VV to minimize the error between reference VV and final VV imposed on motor terminals. The optimization algorithm dose not increase the system's complexity much and can be intuitively understood by a graphical interpretation. Experiment comparisons between the proposed strategy and some existing DTC methods are conducted on a 0.55-kW IM platform. The proposed DTC method has proven to achieve better steady-state performance, while retaining fast dynamic response of TDTC. Furthermore, the proposed method can obtain almost constant average switching frequency in the entire speed range, especially with rated load, due to the utilization of proportional-integral type torque regulator.

Hydrophobic metallic surfaces have attracted much academic and industrial interest due to their promising applications in various fields. Typically, hydrophobicity in metallic materials can be realized by micro/nanostructures and chemical treatment. However, both fragile rough surfaces and low-surface-energy fluorinated silanes are prone to wear and abrasion, leading to the loss of hydrophobicity. In this experiment, we demonstrated a facile and potentially low-cost methodology to fabricate hydrophobic surfaces by integrating a mechanically durable nickel skeleton with an interconnected microwall array filled with hydrophobic poly(tetrafluoroethylene) (PTFE). The interconnected metal frames prevented the removal of the hydrophobic material by abradants, and good hydrophobicity was preserved after more than 1000 cycles of linear abrasion under a local pressure of ∼0.12 MPa. The fabricated surfaces exhibited enhanced anti-icing properties with water droplets compared to unprocessed nickel surfaces. The prepared surfaces also showed superior flexibility. No obvious fracture was observed even after 300 cycles of buckling while the hydrophobic performance was still maintained. The surfaces designed here could provide effective guidance to manufacture large-area surfaces in nickel and other metallic materials that require flexibility, hydrophobic properties, and anti-icing functions for harsh applications.

This paper presented a novel six-dimensional hyperchaotic system and constructed a new chaotic communication encryption method to take advantage of every dimensional sequence of the system. Based on the existing four-dimensional Lorenz system, a new six-dimensional hyperchaotic system is proposed and some related dynamic characteristics of the system are analyzed. To improve the security of communication, the signals are decomposed into n groups of linearly independent data, and the n groups of data are linked with n-dimensional sequence s of the system. A circuit simulation experiment is performed to verify the effectiveness of the method. The experimental results show that combining $$n$$ groups of linearly independent data with n-dimensional chaotic sequences increases the utilization of chaotic sequences and improves the security of secure communication.

To study the effects of exogenous metabolic intermediates and antioxidant on Nannochloropsis oculata microalgae strain, the growth performance, biomass productivity, photosynthetic efficiency, and total lipid content were investigated by lab-scale cultivation experiments. Specifically, N. oculata was cultured in f/2 medium supplemented with different concentrations of citric acid or malic acid (0.050, 0.150, 0.750 g L−1) and KI (0.025, 0.050, 0.100, and 0.500 g L−1) to examine the physiological and biochemical effects on the widely distributed marine algae N. oculata. Results showed that the biomass and photosynthetic efficiency showed a downward trend with increasing citric acid and malic acid concentrations, and the low concentrations of metabolic intermediate treatments could enhance the lipid accumulation. The highest lipid content (0.295 or 0.245 g total lipid per gram of dry biomass) was found in cells treated with 0.15 g L-1 of citric acid and malic acid, which was about 28.45% and 6.99% higher than that growing in the culture lacking metabolic intermediates. Compared with malic acid, citric acid had better effect. Furthermore, potassium iodide (KI), an antioxidant, could also boost the lipid content of N. oculata with slight declining biomass productivity, and the highest lipid content (0.300 g total lipid per gram of dry biomass) was found in cells treated with 0.100 g L-1 of KI, which was about 28.08% higher than that growing in the culture lacking KI, indicating that KI may be a potential factor to increase the lipid content of algae cells. These findings not only provide insight into the response mechanism of N. oculata to exogenous metabolic intermediates and antioxidant but also help further broaden the key regulatory factors involved in the lipid accumulation within algal cells.

A power management system is a critical component of the system which needs Li-ion battery packs for power supply. This paper proposes a fully integrated, high-precision, and high-reliability Integrated Circuit (IC) for the power management system of Li-ion battery packs. It has full protection circuits including overvoltage, overtemperature, and overcurrent circuits with measuring voltage accuracy of 0.2 mV and a 15-bit internal Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC). This IC is designed to protect the system automatically and measure the battery cells’ voltage, temperature, and charging or discharging current with high precision. It also provides an I2C interface to communicate with an external Microcontroller Unit (MCU), making it achievable to perform battery cells’ voltage balancing and SOC estimation with 0.1% estimation accuracy in an hour.

Lignin has been used as a sustainable and eco-friendly filler in composite fibers. However, lignin aggregation occurred at high lignin content, which significantly hindered the further enhancement of fiber performance. The incorporation of graphene oxide (GO) enhanced the mechanical properties of the lignin/poly(vinyl alcohol) (PVA) fibers and affected their structure. With the GO content increasing from 0 to 0.2%, the tensile strength of 5% lignin/PVA fibers increased from 491 MPa to 631 MPa, and Young's modulus increased from 5.91 GPa to 6.61 GPa. GO reinforced 30% lignin/PVA fibers also showed the same trend. The tensile strength increased from 455 MPa to 553 MPa, and Young's modulus increased from 5.39 GPa to 7 GPa. The best mechanical performance was observed in PVA fibers containing 5% lignin and 0.2% GO, which had an average tensile strength of 631 MPa and a Young’s modulus of 6.61 GPa. The toughness values of these fibers are between 9.9-15.6 J/g, and the fibrillar and ductile fracture microstructure were observed. Structure analysis of fibers showed that GO reinforced 5% lignin/PVA fibers had higher crystallinity, and evidence of hydrogen bonding among GO, lignin, and PVA in the gel fibers was revealed. Further, water resistance and swelling behavior of composite PVA fibers were studied to further evidence the structure change of composite fibers.

Carbonized cotton fibers (CCFs) were prepared by the carbonization of commercial cottons at 700, 800 and 900 °C. The following characterizations indicated that the properties of the obtained CCFs could be effectively tuned by the carbonization temperatures. Containing both high conductivity and high aspect ratio, the CCFs could be used as the conductive agents for the construction of the integrated organic cathodes in lithium ion batteries (LIBs). With the optimized ratio of CCF from 900 °C, the organic LIB cathodes showed a high specific capacity of 135 mA h g−1 at a current density of 0.05 A g−1 and an impressive cyclizing stability by keeping 90.5% of the highest capacity value after 500 cycles at 0.5 A g−1. The moderate mechanical stability of the CCF supported organic cathode enabled the further fabrication of flexible LIBs, which manifested stable performances at various bent states, confirming the potentials of CCFs in flexible energy storage devices.

The tip-leakage vortex (TLV) cavitation is a challenging issue for a variety of axial hydraulic turbines and pumps from both technical and scientific viewpoints. The flow characteristics of the TLV cavitation were widely studied in the past decades, but the knowledge about the tip-leakage cavitating flow is still limited. The present paper reviews the progresses in the researches of the TLV cavitation, including the numerical methods for the TLV cavitation, the flow characteristics of the TLV, the influences of the TLV cavitation on the local flow field and the control strategies of the TLV cavitation. It is indicated that the non-condensable gas may play an important role in the development of the TLV cavitation, and this fact should be considered during a careful simulation of the TLV cavitation. It is also suggested that the development of the TLV cavitation will significantly influence the distributions of the vorticity and the turbulence kinetic energy. Due to the complexity of the TLV cavitation, it is still an open question how to suppress the TLV cavitation in a simple but effective way. Finally, based on these understandings, some advanced topics for the future work are suggested to further promote the study of the TLV cavitation, for a deeper knowledge about the TLV cavitation.

Broadband transmitted wavefront measurement is a detection method that uses transmitted wavefronts at a few specific wavelengths though a function of Zernike coefficients and wavelength to predict other transmitted wavefronts at any wavelength within a certain range. This method is used when the designed wavelength of the interferometer and the detection wavelength are different. The function of the Zernike coefficients and wavelength can be expressed by the Conrady formula which can be used to describe a monotonic function curve or a function curve with an inflection point. Two methods, i.e., solving and fitting, can be used to determine the coefficients of the Conrady formula. Owing to the inevitable errors in the actual measurements, the fitting method is preferred to determine the coefficients of the Conrady formula. However, by analyzing the Conrady formula, it was found that the curve obtained by fitting the Conrady formula is a monotonic curve. This method cannot be used to obtain a curve with an inflection point or a slow-changing curve in the long waveband. In this paper, we propose an improved data fitting approach that transforms the Conrady formula into a polynomial formula to fit a given set of data for determining the Conrady formula coefficients. The correctness of the method was verified via simulations. Finally, the feasibility of the proposed method was verified by changing the light source and using the Fizeau interferometer to measure the transmitted wavefront of the doublet lens. To ascertain the feasibility of using visible light to predict the invisible light band, a near-infrared 1064 nm light source was added to the experimental set-up to broaden the range of the transmitted wavefront prediction waveband. Experimental results showed that the conversion polynomial fitting method can be used to obtain monotonic curves and the curve with an inflection point and a slow-changing curve in the long waveband, thereby mitigating the limitation of directly fitting the Conrady formula using a set of data points. Furthermore, using this method, we verified that the visible light can be used to predict the transmitted wavefront at any wavelength in the invisible light band. This observation is highly significant for the practical applications of the broadband transmitted wavefront measurement technique.

Optical dynamic measurements are widely used for non-contact vibration, continuous deformation, or moving objects. Various measurement techniques were developed for different deformation amplitudes. This paper reviews three types of technique for different measurement ranges: interferometric techniques for deformation or vibration (nanometer to sub-millimeter amplitude) whose measurement accuracies rely on phase extraction of interferometric signal; imaging based techniques for deformation or vibration (micrometer to centimeter amplitude) with the aid of moire, structured light, and man-made speckles, whose sensitivities is from 1/100 to 1/10 pixel; and videometrics for large deformation or movement detection (greater than centimeter amplitude). Many research groups have improved measurement capabilities for these three techniques to meet particular industrial application requirements.

The conventional predictive torque control (PTC) for three-phase open-end winding permanent magnet synchronous motor (OEW-PMSM) has the following disadvantages: tedious tuning of weighting factors, large ripples of zero-sequence current, electromagnetic torque, and stator flux. To overcome the above problems, a PTC based on weighting factorless and finite control set (FCS) optimization is proposed in this article. First, a deadbeat control strategy is proposed to convert the control of zero-sequence current, electromagnetic torque, and stator flux into the control of stator voltage vector. Since the equivalent control objects have the same unit, the weighting factors are not required. Second, a two-step optimization scheme for FCS is proposed to reduce the ripples of zero-sequence current, electromagnetic torque, and stator flux. Finally, an optimized pulsewidth modulation (PWM) strategy, which can help to reduce the switching frequency, is proposed. The feasibility and effectiveness of the proposed PTC strategy is verified by experiments on a 1-kW OEW-PMSM.

Network function virtualization (NFV) and software defined networking (SDN) have recently introduced together, which show great potential in openness, innovation, flexibility and scalability of the networks. Embedding SDN/NFV-enabled service function chain (SFC) has been considered as an efficient way to achieve the end-to-end communication. Considering the multiple users’ delay diversities oriented to future networks, from the perspective of network operators, determining the placement of virtual network functions (VNFs) and routing the service paths is a challenging problem. However, the traditional solutions (e.g., exact, heuristic, meta-heuristic, game, etc.) based on the SFC dynamic embedding problem (SFC-DMP) follow the strong assumptions as usual, which might limit their applications in dynamic and complex network scenarios. To address this narrow, we are motivated to present a novel approach for handling SFC-DMP in the cloud datacenter networks that simultaneously combines the quantum genetic algorithm (QGA) and fuzzy logic. Simulation results show the efficient performance of our proposal.

In the process of drug carrier design, lysosome degradation in cells is often neglected, which makes a considerable number of drugs not play a role. Here, we have constructed a tumor treatment platform (Apn/siRNA/NLS/HA/Apt) with unique lysosomal escape function and excellent cancer treatment effect. Apoferritin (Apn) has attracted more and more attention because of its high uniformity, modifiability, and controllability. Meanwhile, its endogenous nature can avoid the risk of immune response being eliminated. We used aptamer modified iron deficient protein nanocages (Apn) to tightly encapsulate the combination of siRNA and NLS (siRNA/NLS) with influenza virus hemagglutinin (HA peptide). After Apn/siRNA/NLS/HA/Apt was targeted into cells, the acidic environment of lysosome led to the cleavage of Apn nanocages, and the release of siRNA/NLS and HA peptide. HA peptide can destroy lysosome membrane, make siRNA/NLS escape lysosome, and enter the nucleus under the action of NLS, resulting in efficient gene silencing effect. This kind of cancer treatment strategy based on Apn nanocage shows high biocompatibility and unique lysosome escape property, which significantly improves the drug delivery and treatment efficiency. Lysosomal escape protein nanocarriers for nuclear-targeted siRNA delivery.

Aiming at the problems of complex structure, fault prone and low accuracy of fault identification of asynchronous motor, this paper proposed a fault location recognition model of asynchronous motor based on AB-CNN (AdaBelief-CNN) intelligent algorithm. Taking asynchronous motor as the application background, an experimental platform is built to collect different types of fault data of asynchronous motor. Firstly, the dimension of the data is reduced by principal component analysis, the convolutional neural network (CNN) is used to carry out forward propagation fault recognition training for asynchronous motor fault data, and output the trained data prediction value. Secondly, through the loss function and AdaBelief optimization algorithm, the asynchronous motor fault location recognition model is optimized. Finally, the accuracy of the fault location identification model is tested with the test data. Comparing with the original CNN network identification model and Adam optimized CNN network (AD-CNN), the proposed solution outperforms other schemes by about 10%.

Microchannel heat sink is widely utilized as one of the effective heat dissipation methods with lower heat transfer temperature difference. In this paper, visual experiment study has been conducted to focus on the inner relationship between heat transfer/flow properties in macroscopic aspect with bubble dynamic characteristics in microcosmic aspect. Results show that along with the increases of Re, the value of convective heat transfer coefficient(h) increases as well. Correspondingly, the pressure drops show a tendency as increasing, decreasing lately, then increasing again. The bubbles in the undergo the same four process: film boiling process, transition process from film to nucleate boiling zone, nucleate boiling process and single-phase convection process. And the variation of pressure drop is one-to-one correspondence with the four heat transfer process. Besides, the triangle pin fin holds the higher heat transfer coefficient, which may be explained from the quantities and the sequence of appearance of bubbles in nucleate heat transfer process. The migration diameter as well as coverage rate of bubbles appears the tendency as ascending firstly then down lately with the increase of Re, which fit the conclusion in macroscopic aspect in heat transfer/flow properties. It could be found that the migration size is mainly influenced by the flow rate as well as the density of bubbles. In this way, the position of bubble occurred is the key point effecting bubble growth time and growth radium. Three zones have been divided to summarize the dynamic behaviors of bubbles in different positions: The migration diameter of bubbles in Zone I in the biggest, with that in Zone II moderate and that in Zone II lowest. The tail of pin fin (Zone I) makes the bubbles more easily to merge the surrounding new nucleated small bubbles to a bigger size, with more residence time to leave the bubble growing bigger. The general growth size of bubbles in ellipse pin fin is smallest, around 0.08 mm and with growth cycle short as 0.616 s. Simultaneously, that of the triangle one is biggest, with the size as 0.099 mm and growth time as 2.112 s.

In this work, selective radiation material was used to change heat transport of hot side, a novel heterostructure cooler, constructed by gold (Au)—bismuth telluride (Bi2Te3) nanowires array was reported experimentally. The heterostructure was fabricated by electrochemical deposition based on porous anodic alumina template (AAO). The Au nanowire cluster array is used as an infrared selective radiation surface to optimize heat transport of the heat side. And the Bi2Te3 nanowires generate thermoelectromotive force between the two sides of the device due to thermoelectric effect. More interestingly, the Au nanowire ends produce an interface between the metal and semiconductor to enhance the temperature difference, as the interfacial phonon scattering suppresses thermal conductivity. The co-effects create a linear-like relationship between the temperature difference and the applied heating strength to make the heating source hide from infrared detection. At a heating temperature of 170 °C, the radiation temperature difference arrives 16 °C in the Au–Bi2Te3 heterojunction, (increased by 200% to that in Bi2Te3 single phase), given by an intriguing demonstration of infrared camouflage effect. The Au–Bi2Te3 nanowires heterojunction device can not only realize infrared camouflage, but also convert the heat into electrical energy, which provides a new idea for the development of materials.

Stereo vision is one of the most crucial operations in many computer vision applications, and stereo matching is its most important step. In recent years, stereo matching has developed in the direction of increasing accuracy and higher computational speed, and the real-time stereo matching algorithm based on hardware architecture has been increasingly emphasized due to its applicability in embedded systems. The most frequently used method on FPGA is the census transform (CT) because of its simple structure and easy parallelization and the high quality of the generated disparity maps, but CT has the drawbacks of mismatches in some regions and dependence on a central pixel. In this paper, an improved CT-based semi-global stereo matching algorithm with pipeline and parallel operation based on FPGA is proposed in order to increase matching accuracy in specific regions while satisfying real-time constraints. In the matching cost step, pixels are divided into two parts, with the two methods calculated to generate the bit-vector feature. A four-path semi-global matching algorithm with twice aggregate is proposed in the cost aggregation stage. The left–right check, mismatching point filling, and the median filter to enhance the final disparity map are also required. The novel algorithm is evaluated on the Middleburry benchmark and implemented on Xilinx ZYNQ-7000 SoCs, which results in a throughput of 640 × 480/60 fps, with 64 disparity levels at 100 MHz. Compared with the related work, we improve the average accuracy by 1.61%, making our approach suitable for real-time embedded systems.

Zn(bdc)(ted)0.5 was synthesized for methane storage application. The effects of various factors such as the mole ratio of reactants and crystallization time on the methane adsorption capacity were ...

Pea starches, in both native (NPS) and retrograded-autoclaved forms (RAPS), were subjected to simulated gastrointestinal (GI) digestion in vitro, their multi-scale structural characteristics, morphological features, molecular distribution and thermal properties were characterized. A gradual increase in the short−/long-range crystallinity, melting enthalpy of gelatinization on increasing digestion time was observed for both the native and retrograded-autoclaved pea starch samples based on the X-ray diffraction, Fourier-transform infrared spectra, solid-state 13CNMR and differential scanning calorimetry measurements. It was especially noticed that the growth rate of crystallinity and double helices, as well as the decrease in Mw values were evidently greater for RAPS than for NPS. To investigate how different molecular fine structure of pea starch substrate affects the gut microbiota shifts and dynamic short-chain fatty acid profile, their resistant starch residues obtained from both native and retrograded-autoclaved pea starch after 8 h of simulated GI tract digestion was used as the fermentation substrate. The levels of acetate, propionate and butyrate gradually increased with the increasing fermentation time for NPS and RAPS. In comparison to the blank control (i.e., the group without the addition of carbohydrate), the fermented NPS and RAPS obviously resulted in an increased abundance of Firmicutes and Bacteroidetes, accompanied by a decrease in Proteobacteria, Actinobacteria and Verrucomicrobia. Both NPS and RAPS promoted different shifts in the microbial community at the genus level, with an increase in the abundance of Bacteroides, Megamonas and Bifidobacterium, as well as a reduction in the abundance of Fusobacterium, Faecalibacterium and Lachnoclostridium in comparison to the blank control samples.

The design of the photocatalytic materials has made a great of remarkable progress in the area of the enhancement photocatalytic activity, but there are still lots of problems such as wide band gap, low utilization of sunlight, low quantum efficiency and poor stability, which further limit the extensive practical applications. Thus, it is a hot research topic and key scientific problem to be solved that how to design and prepare the catalysts, which can respond to visible and near-infrared light in sunlight. Inspired by efficient nonlinear optical upconversion materials, upconversion-based nanocomposites can indirectly broaden the absorption ranges of semiconductors by converting the captured long-band visible and near-infrared incident light into high-energy short-band visible or ultraviolet light, which can be adopted as the promising candidate in wide-spectral-light-activating photocatalytic materials coupling with conventional semiconductors. According to our recent works and literature reports, recent review summarizes the research progress of photocatalytic materials with upconversion effect on photolysis of water for hydrogen production, degradation of organic and inorganic pollutants, reduction of CO2 and photodynamic therapy. The prepared nanocomposites can suppress the recombination of electrons and holes, and greatly improve the photocatalytic efficiency by the synergistic effect. It maybe stimulates a great interest in rational design and preparation of efficient full-spectrum photocatalytic systems and their wide application in solar energy conversion.

In this article, we present a dual-stator structure-parallel fault-tolerant machine (DSSPFTM). In this machine, the radial-flux dual-stator structure with a higher density is adopted to the fault-tolerant system. For better performance in fault condition, the combination of permanent-magnet component (PMC) and reluctance component (RC) in the rotor and large-opening slot is proposed. Because of the same poles and torque-variation principle, the PMC and RC are combined. The PMC is devised to supply most of the torque in normal conditions, while the RC provides enough self-inductance for limiting current under short-circuit (SC) occasion. Most of the flux leakage is separated from the active flux and the overload ability is improved. The design process of DSSPFTM is described in steps and details. Based on the fundamental of maximum torque under normal conditions, PMC and RC are integrated together. The end flux leakage originating from the adjacency of RC to PMC and the effect of RC length on torque are analyzed. The back-EMF, torque, inductance, loss, efficiency, and SC analysis are demonstrated. The stress and deformation distribution of the rotor and the comparison with the traditional structure are conducted. A prototype DSSPFTM is designed and manufactured. The experiments accord with simulations, indicating that the DSSPFTM with fault tolerance can improve the torque density effectively.