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Although Taxodium hybrid 'Zhongshanshan' 406 (Taxodium mucronatum Tenore ×  Taxodium distichum ; Taxodium 406) is an extremely flooding-tolerant woody plant, the physiological and molecular mechanisms underlying acclimation of its roots to long-term flooding remain largely unknown. Thus, we exposed saplings of Taxodium 406 to either non-flooding (control) or flooding for 2 months. Flooding resulted in reduced root biomass, which is in line with lower concentrations of citrate, α-ketoglutaric acid, fumaric acid, malic acid and adenosine triphosphate (ATP) in Taxodium 406 roots. Flooding led to elevated activities of pyruvate decarboxylase, alcohol dehydrogenase and lactate dehydrogenase, which is consistent with higher lactate concentration in the roots of Taxodium 406. Flooding brought about stimulated activities of superoxide dismutase and catalase and elevated reduced glutathione (GSH) concentration and GSH/oxidized glutathione, which is in agreement with reduced concentrations of O2− and H2O2 in Taxodium 406 roots. The levels of starch, soluble protein, indole-3-acetic acid, gibberellin A4 and jasmonate were decreased, whereas the concentrations of glucose, total non-structural carbohydrates, most amino acids and 1-aminocyclopropane-1-carboxylate (ACC) were improved in the roots of flooding-treated Taxodium 406. Underlying these changes in growth and physiological characteristics, 12,420 mRNAs and 42 miRNAs were significantly differentially expressed, and 886 miRNA–mRNA pairs were identified in the roots of flooding-exposed Taxodium 406. For instance, 1- aminocyclopropane- 1 -carboxylate synthase 8 (ACS8) was a target of Th-miR162-3p and 1 -aminocyclopropane- 1 -carboxylate oxidase 4 (ACO4) was a target of Th-miR166i, and the downregulation of Th-miR162-3p and Th-miR166i results in the upregulation of ACS8 and ACO4 , probably bringing about higher ACC content in flooding-treated roots. Overall, these results indicate that differentially expressed mRNA and miRNAs are involved in regulating tricarboxylic acid cycle, ATP production, fermentation, and metabolism of carbohydrates, amino acids and phytohormones, as well as reactive oxygen species detoxification of Taxodium 406 roots. These processes play pivotal roles in acclimation to flooding stress. These results will improve our understanding of the molecular and physiological bases underlying woody plant flooding acclimation and provide valuable insights into breeding-flooding tolerant trees. [ABSTRACT FROM AUTHOR]

The band gap is a key parameter in semiconductor materials that is essential for advancing optoelectronic device development. Accurately predicting band gaps of materials at low cost is a significant challenge in materials science. Although many machine learning (ML) models for band gap prediction already exist, they often suffer from low interpretability and lack theoretical support from a physical perspective. In this study, we address these challenges by using a combination of traditional ML algorithms and the 'white-box' sure independence screening and sparsifying operator (SISSO) approach. Specifically, we enhance the interpretability and accuracy of band gap predictions for binary semiconductors by integrating the importance rankings of support vector regression (SVR), random forests (RF), and gradient boosting decision trees (GBDT) with SISSO models. Our model uses only the intrinsic features of the constituent elements and their band gaps calculated using the Perdew–Burke–Ernzerhof method, significantly reducing computational demands. We have applied our model to predict the band gaps of 1208 theoretically stable binary compounds. Importantly, the model highlights the critical role of electronegativity in determining material band gaps. This insight not only enriches our understanding of the physical principles underlying band gap prediction but also underscores the potential of our approach in guiding the synthesis of new and valuable semiconductor materials. [ABSTRACT FROM AUTHOR]

Linalool is an important substance in the synthesis of fragrances owing to its unique aroma. However, the application of linalool is limited due to its low stability and rapid volatilization. Supramolecular inclusion technology plays an important role in improving the stability and volatility of fragrance and endows fragrance with excellent heat‐controlled release properties. In this study, inclusion complexes were prepared with two acyclic cucurbit[n]urils (M1 and M2) to improve the thermal stability of linalool, their binding behaviours were investigated by NMR, XRD, FT‐IR and Molecular Docking, confirming the formation of the host‐guest inclusion complexes. The stoichiometry of inclusion complexes was 1:1 by Job's plot and the binding constant was determined by fluorescence titration. The TG and heat‐controlled release experiment indicated that the inclusion complexes have higher thermal stability. This study provides a new idea and method for the development of linalool series spices. [ABSTRACT FROM AUTHOR]

• Human metapneumovirus (HMPV) is an important respiratory pathogen that causes acute respiratory tract infection in children ≤5 years old. • The prevalence peak of HMPV in southern China appeared between March and May. • Respiratory syncytial virus is the most common respiratory virus coinfected with HMPV in children. • The predominant subtype of HMPV in this area is B1, followed by A2c subtype. • Long sunshine duration might decrease the HMPV prevalence. This study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. 14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. HMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. HMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence. [ABSTRACT FROM AUTHOR]

As an important part of rotating machinery, the failure of bearings will cause serious vibration and noise of mechanical equipment, which will affect the normal operation of the equipment and even lead to economic losses and casualties. To accurately and efficiently diagnose the working state and fault category of bearings, a new fault diagnosis method for rolling bearings based on the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), weighted permutation entropy (WPE) and adaptive chaotic particle swarm optimization back propagation (BP) neural network (ACPSO-BP) was proposed. CEEMDAN and WPE were used to extract fault features and optimize the feature vector by mean domain specification principles. ACPSO optimizes the convergence speed and recognition accuracy of the BP neural network by introducing an adaptive tent mapping interval. The experimental results on bearing data from Western Reserve University and actual wind turbine data show that the proposed diagnosis method can achieve high fault recognition accuracy with a small number of training samples. [ABSTRACT FROM AUTHOR]

Uridine diphosphate (UDP)-sugars are important metabolites involved in the biosynthesis of polysaccharides and may be important signaling molecules. UDP-glucose 4-epimerase (UGE) catalyzes the interconversion between UDP-Glc and UDP-Gal, whose biological function in rice (Oryza sativa) fertility is poorly understood. Here, we identify and characterize the botryoid pollen 1 (bp1) mutant and show that BP1 encodes a UGE that regulates UDP-sugar homeostasis, thereby controlling the development of rice anthers. The loss of BP1 function led to massive accumulation of UDP-Glc and imbalance of other UDP-sugars. We determined that the higher levels of UDP-Glc and its derivatives in bp1 may induce the expression of NADPH oxidase genes, resulting in a premature accumulation of reactive oxygen species (ROS), thereby advancing programmed cell death (PCD) of anther walls but delaying the end of tapetal degradation. The accumulation of UDP-Glc as metabolites resulted in an abnormal degradation of callose, producing an adhesive microspore. Furthermore, the UDP-sugar metabolism pathway is not only involved in the formation of intine but also in the formation of the initial framework for extine. Our results reveal how UDP-sugars regulate anther development and provide new clues for cellular ROS accumulation and PCD triggered by UDP-Glc as a signaling molecule. UDP-Glc and its derivatives induce the expression of NADPH oxidase genes, inducing ROS-triggered PCD as signaling molecules, but also regulate pollen wall development as metabolites. [ABSTRACT FROM AUTHOR]

This study delves into the intricate usage and interpretation issues of the Chinese term "體" (tǐ) in Xuanzang's translation of the Abhidharmakośa (AKBh[X]) by providing a Sanskrit-Chinese comparative investigation. Xuanzang's translations are pivotal in understanding certain Abhidharma scriptures, as some of them are the sole complete versions available. This study focuses on the term "體" in AKBh[X], evaluating its usage in relation to 16 corresponding Sanskrit equivalents and the instances where Xuanzang introduced "體" without a Sanskrit equivalent. The analysis uncovers translation errors, potential misinterpretations, and the lack of clarity in certain contexts, emphasizing the need for readers to be cautious and consult additional sources for a comprehensive understanding of his translations. [ABSTRACT FROM AUTHOR]

The effect of solution treatment and rare-earth Yb on the microstructure and corrosion resistance of the AlSi11Cu3 alloy was investigated. Optical microscopy, scanning electron microscopy, and X-ray diffraction results revealed that the addition of 0.9 wt.% Yb remarkably refined the α-Al and Si phase, and solution treatment further improved the microstructure and dissolved the Al2Cu phase. Immersion corrosion testing including weight loss and hydrogen evolution showed that the addition of 0.9 wt.% Yb and solution treatment prompted the best corrosion resistance of the alloy. Similarly, electrochemical test results showed that the corrosion current density of the AlSi11Cu3 + 0.9 wt.% Yb + solution treatment (4.87 μA·cm−2) sample was lower than that of the matrix (18.51 μA·cm−2) and the impedance value of the former (588.87 Ω·cm2) was higher than that of the latter (120.01 Ω·cm2). The solution treatment and addition of 0.9 wt.% Yb remarkably refined the cathode phase and reduced the pitting corrosion. In addition, scanning Kelvin probe force microscopy showed that Al2Cu and α-Al have the largest potential difference, so the dissolution of Al2Cu greatly reduced the potential difference between the second phase and α-Al and decreased the generation of corrosion micro-cells, thus improving the corrosion resistance of the alloy. [ABSTRACT FROM AUTHOR]

Circular RNA (circRNA) is a newly discovered noncoding RNA that regulates gene transcription, binds to RNA-related proteins, and encodes protein microRNAs (miRNAs). The development of molecular biomarkers such as circRNAs holds great promise in the diagnosis and prognosis of clinical disorders. Importantly, circRNA-mediated maternal-fetus risk factors including environmental (high altitude), maternal (preeclampsia, smoking, and chorioamnionitis), placental, and fetal (preterm birth and low birth weight) factors are the early origins and likely to contribute to the occurrence and progression of developmental and pediatric cardiopulmonary disorders. Although studies of circRNAs in normal cardiopulmonary development and developmental diseases have just begun, some studies have revealed their expression patterns. Here, we provide an overview of circRNAs' biogenesis and biological functions. Furthermore, this review aims to emphasize the importance of circRNAs in maternal-fetus risk factors. Likewise, the potential biomarker and therapeutic target of circRNAs in developmental and pediatric lung diseases are explored. [ABSTRACT FROM AUTHOR]

This paper develops a new hybrid method based on an improved ant colony optimization algorithm that incorporates pattern search (IACO-PS) for determining the location of faults in a distribution network. The performance of the conventional ant colony optimization (ACO) algorithm is improved using the opposite-based learning strategy to generate the initial population and adding a weight coefficient into the pheromone update mechanism to dynamically adjust the pheromone volatilization factor. The hybrid IACO-PS algorithm combines the individual strengths of ACO and PS. In addition, the fitness function is constructed by counting the false and missing fault information into the fault variable. In optimizing benchmark function experiments, the proposed hybrid IACO-PS presents a superior performance when compared to other improved versions of ACO. The effectiveness of the proposed approach is corroborated by tests performed on an IEEE 134-bus network. Simulation results show that the proposed hybrid IACO-PS method can determine the location of a fault even in the presence of fault distortion. In addition, it is immune to noise and data loss errors. Finally, the method proposed in this paper significantly outperforms other published fault location methods, and it can accurately locate faults and identify the type of distortion. [ABSTRACT FROM AUTHOR]

In this paper, reverse transition entropy (RTE) is proposed and combined with refined composite multi-scale analysis and generalized fractional-order entropy to construct the refined composite multi-scale reverse transition generalized fractional-order complexity-entropy curve (RCMS-RT-GFOCEC). This measure aims to characterize and identify different complex time series. First, RTE is used to extract the static and dynamic transition probabilities of the temporal structure. Then, the distribution area and variation law of the visualization curves are adopted to characterize different time series. Finally, the time series are identified by the multi-scale curves of RTE, H α min , and C α max . The characteristic curves (H q min and C q max ) of the refined composite multi-scale q complexity-entropy curves (RCMS-q-CECs) for the comparative analysis are irregular. The experimental results indicate that the RCMS-RT-GFOCEC method could effectively characterize both artificial and empirical temporal series. Moreover, this method can effectively track the dynamical changes of rolling bearing and turbine gearbox time series. The accuracies of the proposed method reach 99.3% and 98.8%, while the recognition rates based on the RCMS-q-CEC method are only 95.7% and 97.8%, suggesting that the proposed method can effectively characterize and identify different complex temporal systems. [ABSTRACT FROM AUTHOR]

(Z)‐jasmone is the most important contribution to the scents of perfumes and cosmetics. However, (Z)‐jasmone is water insoluble and highly volatile, which limits its development and application. Inclusion technology has become a promising strategy to improve the solubility and stability of hydrophobic small molecules. Here, we used saturated aqueous solution and freeze‐drying method to prepare solid inclusion complexes of (Z)‐jasmone and three acyclic cucurbit[n]urils (ACBs, M1‐M3), and studied their binding behaviours by fluorescence spectroscopy, NMR, XRD, FT‐IR, TG and DSC, confirming the formation of the host‐guest inclusion complexes. The stoichiometry of inclusion complexes was 1:1 by Job's plot. The inclusion complexes exhibited better water solubility, higher thermal stability and heat‐controlled release comparing with that of native (Z)‐jasmone. This work uncloses a new strategy to enhance the performance of essential oil and flavours/fragrances and further application in the field of cosmetic and food industry. [ABSTRACT FROM AUTHOR]

In karst areas, groundwater has high concentrations of carbon dioxide. It causes decalcification of cement-based materials by reacting with calcium hydroxide and calcium silicate hydrate. Therefore, the corrosion by CO 2 -rich groundwater has become a significant concern as it may reduce the service life of concrete structure. Based on the chemical reactions, the corrosion can be divided into leaching corrosion, carbonic acid corrosion, and acid corrosion. Calcium carbonate formation and dissolution are critical steps in corrosion process. The loss of calcium from cement results in cracking and spalling of the cement-based materials. The environmental and material factors had a significant effect on the corrosion rate. Based on the study in simulated karst water, adding supplementary cementitious materials or low-calcium alkali-activated materials can improve the corrosion resistance of the cementitious materials. [ABSTRACT FROM AUTHOR]

To effectively mitigate the commutation failure (CF) of the line-commutated converter high-voltage direct current (LCC-HVDC) transmission system, a dynamic series voltage compensator (DSVC) scheme is proposed. The DSVC consists of three integrated gate-commutated thyristor (IGCT)-based full-bridge submodule (FBSM) chains to match the bulk power transmission of the LCC-HVDC. Inserted between the transformer and the AC port of the inverter, the DSVC assists the commutation process by superposing the transient voltage to the AC line voltage and increasing the commutation margin of the inverter valve. Operation and control strategies, which are two critical techniques for the DSVC, are designed based on the working states of the FBSMs, assisting the commutation process and balancing the DSVC capacitor dynamic voltages. The CF detection method is another critical technique of the DSVC control and is improved considering the reverse time of the LCC-HVDC thyristors. Compared with the topologies proposed in existing literature, the DSVC has better performances in safe and stable operation due to the urgent control strategy considering situations beyond its ability. A detailed EMT simulation shows that the DSVC can respond quickly to mitigate CFs and validate the effectiveness of the overall design and key techniques. Furthermore, the operation and control strategy can limit the current stress once it is beyond the capability of the DSVC, which guarantees its feasibility and practicability. [ABSTRACT FROM AUTHOR]

Here we developed a continuous flow microreactor system to synthesis N-benzoylpiperazine, which is an important intermediate of novel nootropic Sunifiram. And the kinetics of the condensation amidation of piperazine and benzoic acid using HATU as coupling reagent was revealed in microreactor. A kinetic model was established, all the reactions kinetics parameters, including the reaction order of each reactant, rate constants, pre-exponential factors and activation energies were acquired. With this model the selectivity vs. reaction temperature/molar flow ratio were obtained to help understand this kind of reaction and further optimize operating conditions. Under the condition of using equivalent piperazine, 95.6% of selectivity and 91.2% of yield were obtained in microreactor with 50 s. To further expand the scope of carboxylic acid, cyclopropanecarboxylic acid was tried as acylating agent, and 92.8% of selectivity and 86.1% of yield were obtained in microreactor. [ABSTRACT FROM AUTHOR]

Superconducting transformer, which used for power supply of the large current superconductor, is faced with the conductor sample current attenuation problem since the existence of joint resistance. A solution is proposed to solve this attenuation problem to make the conductor sample current controllable. The adaptive Proportion Integration Differentiation (PID) control strategy based on learning rates (η) Radial Basis Function (RBF) neural network (NN) is an improvement over the conventional PID algorithm. The algorithm is applied to obtain the optimal parameters for the PID controller to the working variations arising from transformer nonlinear dynamics. The controller system is carried out on the superconducting conductor test platform of the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). The results showed that the overall deviation of the system was within 0.2%. The performance of the proposed approach is validated by superconductor experiments under practical conditions. [ABSTRACT FROM AUTHOR]

The construction of a sustainable transport network for people or goods will gain and harm mobility depending on their nature and implementation, using new technology and business models. The regular mobile handoff and replacement of connections allow the efficient mobility management of asynchronous wireless transfer mode (ATM) networks. Hence, the design of the broad spectrum usability network architecture for public ATM systems has been given considerable attention in the literature. Since it has been done on the critical subject of estimating user mobility and the prediction, which aims to improve communication efficiency and the bandwidth efficiency of the underlying system architecture, this article addresses the problem by developing the impact of hierarchical framework of service on transportation and traffic pattern (HFSTTP). The growth in mobile Internet and the use of mobile devices over the last decade allowed for omnipresent information on traffic. With the growing use of unique mobile apps, the number of routing users has evolved to be sufficiently large to interrupt the traffic flow pattern. Modern carriage systems and urban logistics improve the efficiency of the transport of goods and slow down the use of road infrastructure. Numerical examples of vehicle traffic include proof of ties between the network traffic and the routing decision‐making layer. The partnership between a cooperative control layer and a lower control layer to optimize freight transport is a second example. The congestion price in all over the world shows how to incorporate the social plan layer in future mobility services. [ABSTRACT FROM AUTHOR]

In the electromagnetic transient (EMT) and transient stability (TS) hybrid simulation, the entire power system is artificially split into two sub-grids, and sub-grids interact with each other via an interface. Thus interface distortions emerge, including latency and errors. The influence of interface latency is quantitated based on a demo circuit containing delayed interaction. Moreover, the principles of improving hybrid simulation interface accuracy are concluded. Inspired by the principles, a novel interface displacement (ID) and dynamic phasor mapping equivalence (DP-ME) interface scheme is proposed. The scheme makes sub-grids at opposite sides of an interface loosely coupled and avoids interface variable form conversion by applying two techniques. 1) Displacement of the partition interface from the converter buses to the control loops and interior of the EMT sub-grid to utilize the built-in inertias. 2) Construction of the DP-ME model to calculate the injected power from EMT to TS sub-grid. Tests based on designed cases and an actual HVAC/DC power grid give credibility to the proposed ID & DP-ME scheme in comparison with full electromagnetic simulation. [ABSTRACT FROM AUTHOR]

Age is a significant contributing factor to the occurrence and progression of cardiovascular disease (CVD). Pharmacological treatment can effectively alleviate CVD symptoms caused by aging. However, 90% of the drugs have failed in clinics because of the loss of drug effects or the occurrence of the side effects. One of the reasons is the disparity between animal models used and the actual physiological levels in humans. Therefore, we integrated multiple datasets from single‐cell and bulk‐seq RNA‐sequencing data in rats, monkeys, and humans to identify genes and pathways with consistent/differential expression patterns across these three species. An approach called "Cross‐species signaling pathway analysis" was developed to select suitable animal models for drug screening. The effectiveness of this method was validated through the analysis of the pharmacological predictions of four known anti‐vascular aging drugs used in animal/clinical experiments. The effectiveness of drugs was consistently observed between the models and clinics when they targeted pathways with the same trend in our analysis. However, drugs might have exhibited adverse effects if they targeted pathways with opposite trends between the models and the clinics. Additionally, through our approach, we discovered four targets for anti‐vascular aging drugs, which were consistent with their pharmaceutical effects in literatures, showing the value of this approach. In the end, software was established to facilitate the use of "Cross‐species signaling pathway analysis." In sum, our study suggests utilizing bioinformatics analysis based on disease characteristics can help in choosing more appropriate animal models. [ABSTRACT FROM AUTHOR]

With the increasing penetration of renewable energies in modern power grids, large amounts of voltage source converters (VSCs) have been installed, resulting in many new transient issues. Electromagnetic transient (EMT) simulation plays an essential role in investigating and solving the issues. However, simulation efficiency plunges when object grids contain multiple VSCs, because each switching event incurs modification or re-decomposition of the network matrix in traditional EMT programs, which is very time-consuming. Thus, this paper proposes a VSC model represented by pulse voltage-current source pairs. Accordingly, a unidirectional loosely-coupled solving algorithm is designed. Synthetically, the authors propose a novel EMT simulation approach adaptive to systems with multiple VSCs. The proposed approach keeps the computational network invariable while sufficiently considers detailed switching events, thereby significantly improving the simulation efficiency of the EMTP program without precision loss. [ABSTRACT FROM AUTHOR]

In order to accurately extract harmonic components in power signals, a harmonic detection method based on variational mode decomposition (VMD) optimized by the genetic algorithm and permutation entropy is proposed. The genetic algorithm optimizes VMD, which can improve the difficulty of parameter selection of VMD. The combination of optimized VMD and permutation entropy can simultaneously utilize the complete decomposition of VMD and the sensitivity to the time of permutation entropy and quickly and effectively filter out various interference signals of power systems. The simulation experiment and engineering application prove that compared with empirical mode decomposition and ensemble empirical mode decomposition harmonic detection methods, this method can effectively filter out noise under a low signal-to-noise ratio and achieve a higher harmonic detection accuracy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Py-ACB is firstly successfully prepared as fluorescent probe for Fe3+. • The probe Py-ACB possessed high selectivity and response speed to Fe3+. • The LOD of the probe for Fe3+ are 2.51 × 10−8 M. • The probe can be used to detect Fe3+ in living cells. Fe3+ is an essential element for human body, misregulation of which in cell are concerned with serious diseases. It is very meaningful to detect Fe3+ in living cells. Here, a novel fluorescent probe (Py-ACB) based on acyclic cucurbituril and pyrene was synthesized. Py-ACB exhibits high selectivity and sensitivity to Fe3+, Fe3+ is coordinated with the carbonyl groups and oxygen atoms of Py-ACB, resulting in reverse photo-induced electron transfer (reverse PET) from pyrene unit to the carbonyl oxygen atoms to induce fluorescence quenching. The binding constant and detection limits of Fe3+ recognized by Py-ACB are 9.26 × 104 M−1 and 2.51 × 10−8 M, respectively, and Py-ACB showed high response speed to Fe3+. More importantly, the probe Py-ACB showed strong fluorescence emission in living cell, which allowed the detection of Fe3+ in live cells by bioimaging. [ABSTRACT FROM AUTHOR]

• The design and development of data acquisition and monitoring systems are based on Super-X requirements. • The plug-in mechanism provides a standard access channel for multi-type devices, which improves system flexibility and extensibility. • The message distribution service through multi-worker solves the slow subscription phenomenon of ZeroMQ. • The combination of long-term and short-term databases is adopted to improve the query efficiency of recent data. To meet the construction requirements of future fusion reactors and other large-scale superconducting magnets, China is building an advanced superconducting conductor experimental device (Super-X) to evaluate the performance of future superconducting components. To ensure the reliability, stability of the Super-X devices and the flexibility, extensibility of the experimental tests, a specialized data acquisition and monitoring system has been designed and developed, which comprises three main components: data acquisition, transmission, and storage. For the data acquisition, a driver plug-in dynamic loading mechanism is employed to shield the diversification of data acquisition devices, thereby providing a unified data interface for upper-level operations. In terms of data transmission, the publish/subscribe (pub/sub) mode of ZeroMQ was utilized to meet the high-speed sampling demands (10 kHz sampling rate) of data transmission. In addition, a data distribution service improvement strategy that employs multiple workers is proposed to enhance subscriber reception capacity and reduce data transmission loss. As for data storage, a combination of short-term and long-term databases is used to improve the efficiency of data queries. The results of testing indicate that the system can satisfy the operational and experimental requirements of the device. [ABSTRACT FROM AUTHOR]

In this paper, a novel hybrid-arm modular multilevel converters (HA-MMCs) topology with DC low voltage operation and fault ride-through capability is proposed for unidirectional HVDC bulk power transmission. The HA-MMCs topology is a combination of two types of converter arms: the half-bridge sub-module based arm (HBSM-arm) and the diagonal bridge sub-module based arm (DBSM-arm). Replacing the traditional HBSM-MMC, the HA-MMCs are operated in current and reactive power control modes during normal conditions and can work as the rectifier or the inverter. Since the DBSM can provide bipolar voltages with unipolar currents, the HA-MMCs need not change its control strategy under DC low voltage conditions caused by the high-impedance faults. Under DC pole-to-pole or pole-to-ground faults, the HA-MMCs can both clear the DC fault current and work as the static synchronous compensator (STATCOM) to provide reactive power to support the AC grid. Compared with other MMC topologies with DC fault ride-through capability, the HA-MMCs topology is more economical for significantly decreasing the number of power devices. The operation states, control strategy and DC low voltage operation capability of the HA-MMCs are presented and simulation results of the LCC-HA-MMC hybrid system using PSCAD/EMTDC validate the characteristics and advantages of the HA-MMCs. [ABSTRACT FROM AUTHOR]

A complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) thresholding denoising method optimized by nonlocal means (NLM) algorithm is proposed in this article. First, in order to enhance the adaptability and the accuracy of the algorithm, a composite screening method based on sample entropy–probability density–Mahalanobis distance for intrinsic mode functions (IMFs) is proposed. According to the proposed screening method, the IMFs are divided into three levels. Second, in order to obtain a threshold which can be adaptively changed, a threshold evaluation criterion is proposed to assist in selecting a suitable threshold. Then, the optimized thresholding denoising algorithm by the NLM is introduced to denoise the IMFs of different levels, in which the NLM algorithm with different parameters is used to smooth the different IMFs. Finally, all IMFs are reconstructed to obtain the denoised signal. The results of numerical simulation and experimental analysis to Doppler, Bumps, Signal3 (randomly generated nonstandard test signal) signals, partial discharge (PD) signals, and real signals show that the method of this article improves shortcomings of the traditional thresholding denoising method, such as inaccurate threshold selection, discontinuity of the data points of the denoised signals, and that the structure of the denoised signal is easily destroyed and the useful small-amplitude part of the denoised signal is easily discarded. The algorithm has better adaptability. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the measurement reproducibility of the maximum diameter on MRI routine sequence (T1WI, T2WI, DWI) and CT in peripheral and central lung cancer, and to provide reference standard for evaluating treatment responses for lung cancer. METHODS: 53 patients with lung cancer underwent CT and 3.0T MR scanning. The maximum diameter was measured according to the RECIST1.1 standard on images of CT (lung and enhanced mediastinal window), MRI T2-BLADE, axial T1-VIBE and DWIb0, DWIb300, DWIb800, respectively. The reproducibility of the diameters was analyzed with intraclass correlation coefficient (ICC), and the distribution of measurement points with the Bland-Altman method. The difference analysis was assessed by paired samples t-test and nonparametric rank sum test, P < 0.05 is considered statistically significant. RESULTS: Reproducibility of diameters derived from routine MRI and CT was good (ICC > 0.75). For peripheral lung cancer, there was no significant difference in diameters between CT and MRI. While for central lung cancer, there was significant difference in diameters measured between using CT and each MRI sequence. However, the diameters derived from T1-VIBE and T2-BLADE were not significantly different from all DWI sequences. CONCLUSIONS: For peripheral lung cancer, the measurement on CT and routine MRI sequences can potentially replace each other after comprehensive consideration of examination purposes, but for central lung cancer, alternative use of CT and MRI in evaluating treatment responses for lung cancer should needs extra attention. The diameter measurement of lung cancer on DWI is consistent with that on T1WI and T2WI, suggesting that DWI can provide functional and morphological information. [ABSTRACT FROM AUTHOR]

With hundreds of spectral bands, the rise of the issue of dimensionality in the classification of hyperspectral images is usually inevitable. In this paper, a restrictive polymorphic ant colony algorithm (RPACA) based band selection algorithm (RPACA-BS) was proposed to reduce the dimensionality of hyperspectral images. In the proposed algorithm, both local and global searches were conducted considering band similarity. Moreover, the problem of falling into local optima, due to the selection of similar band subsets although travelling different paths, was solved by varying the pheromone matrix between ants moving in opposite directions. The performance of the proposed RPACA-BS algorithm was evaluated using three public datasets (the Indian Pines, Pavia University and Botswana datasets) based on average overall classification accuracy (OA) and CPU processing time. The experimental results showed that average OA of RPACA-BS was up to 89.80%, 94.96% and 92.17% for the Indian Pines, Pavia University and Botswana dataset, respectively, which was higher than that of the benchmarks, including the ant colony algorithm-based band selection algorithm (ACA-BS), polymorphic ant colony algorithm-based band selection algorithm (PACA-BS) and other band selection methods (e.g. the ant lion optimizer-based band selection algorithm). Meanwhile, the time consumed by RPACA-BS and PACA-BS were slightly lower than that of ACA-BS but obviously lower than that of other benchmarks. The proposed RPACA-BS method is thus able to effectively enhance the search abilities and efficiencies of the ACA-BS and PACA-BS algorithms to handle the complex band selection issue for hyperspectral remotely sensed images. [ABSTRACT FROM AUTHOR]

With the increasing applications of high‐voltage direct current inverters in heavy‐load grids, commutation failures (CFs) pose a severe threat to the safe and stable operation of power systems. This study first sorts methods of CF inhibition into different categories and then investigates their effectiveness, adaptability and limitations. Considering the economic benefits and applicability, CF inhibition calls for integrated methods involving supplementary power devices, control strategies and prediction techniques. Finally, this study makes clear potential future research directions, suggesting first control potential is exploited by machine learning‐based control, and then auxiliary devices to be added if necessary. [ABSTRACT FROM AUTHOR]

Conventional brain-computer interface (BCI) systems have been facing two fundamental challenges: the lack of high detection performance and the control command problem. To this end, the researchers have proposed a hybrid brain-computer interface (hBCI) to address these challenges. This paper mainly discusses the research progress of hBCI and reviews three types of hBCI, namely, hBCI based on multiple brain models, multisensory hBCI, and hBCI based on multimodal signals. By analyzing the general principles, paradigm designs, experimental results, advantages, and applications of the latest hBCI system, we found that using hBCI technology can improve the detection performance of BCI and achieve multidegree/multifunctional control, which is significantly superior to single-mode BCIs. [ABSTRACT FROM AUTHOR]

A complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) thresholding denoising method optimized by nonlocal means (NLM) algorithm is proposed in this article. First, in order to enhance the adaptability and the accuracy of the algorithm, a composite screening method based on sample entropy–probability density–Mahalanobis distance for intrinsic mode functions (IMFs) is proposed. According to the proposed screening method, the IMFs are divided into three levels. Second, in order to obtain a threshold which can be adaptively changed, a threshold evaluation criterion is proposed to assist in selecting a suitable threshold. Then, the optimized thresholding denoising algorithm by the NLM is introduced to denoise the IMFs of different levels, in which the NLM algorithm with different parameters is used to smooth the different IMFs. Finally, all IMFs are reconstructed to obtain the denoised signal. The results of numerical simulation and experimental analysis to Doppler, Bumps, Signal3 (randomly generated nonstandard test signal) signals, partial discharge (PD) signals, and real signals show that the method of this article improves shortcomings of the traditional thresholding denoising method, such as inaccurate threshold selection, discontinuity of the data points of the denoised signals, and that the structure of the denoised signal is easily destroyed and the useful small-amplitude part of the denoised signal is easily discarded. The algorithm has better adaptability. [ABSTRACT FROM AUTHOR]

Superconducting magnets are widely used in nuclear fusion reactors, high-energy particle accelerators, steady-state high magnetic fields, etc. Higher magnetic fields and higher operating temperatures are two application trends. High temperature superconducting (HTS) materials are the only choice for high temperature and high field magnets in the future. The first- and second-generation HTS materials have a typical tape structure; their critical performance is magnetic field angle and temperature dependent. A new test facility is developed for an experimental study on the an-isotropic critical current. The field angle can be changed from 0° to 360° with a resolution of 1°. The rotation deviation angle is measured to be 0.2° when the upper part rotates 90°. The temperature can be changed from 4.2 to 80 K. The temperature errors are ±50, ±80, and ±135 mK for 4.2–20, 20–40, and 40–80 K, respectively. The angle dependence of critical current (Ic) of the tested rare-earth barium copper oxide tape within 0°–30° is strong. From 30° to 90°, the sample Ic almost does not change with the magnetic field angle. The implementation of the project will not only promote the structural optimization of HTS tapes but also promote the miniaturization and economical application of HTS magnets. [ABSTRACT FROM AUTHOR]

Rechargeable aluminum batteries are of interest owing to the nonflammability of Al metal anode and the ionic liquid electrolytes together with the low cost and high capacity of Al metal anode. However, the ionic liquid electrolytes are also moisture sensitive and highly corrosive, bringing about irreversible activity loss, undesired gas production and destructive leakage corrosion, which thus hinder the practical application of rechargeable aluminum batteries. Herein, a gel polymer electrolyte is designed via in-situ cross-linking polymerization of ethyl acrylate (EA) monomer and pentaerythritol acrylate (PETEA) crosslinker in high molar ratio of AlCl 3 /1-ethyl-3-methylimidazolium chloride (EMIC) ionic liquid. This gel polymer electrolyte exhibits an ionic conductivity of 1.46 × 10−3 S cm−1, a wide electrochemical window up to 3.0 V (vs. Al), alleviated moisture sensitivity and appreciable interfacial stability at room temperature. The assembled solid-state Al//graphite batteries with the gel polymer electrolyte deliver stable capacities of ∼90 mAh g−1 for 1000 cycles at the current density of 100 mA g−1 at both ambient temperature and −10 °C. Even with high-loading graphite cathode of 11 mg cm−2, capacities of ∼60 mAh g−1 can still be obtained for 300 cycles. This work provides a promising strategy for developing reliable and flexible rechargeable aluminum batteries. [Display omitted] • PEA-GPE is prepared via a facile in-situ crsosslinking polymerization strategy. • PEA-GPE displays a wide electrochemical window up to 3.0 V (vs. Al). • The Al//graphite batteries maintain stable capacities of ∼90 mAh g−1 for 1000 cycles. [ABSTRACT FROM AUTHOR]

Meng, X.; Zhang, S., and Zang, S., 2019. Lake wetland classification based on an SVM-CNN composite classifier and high-resolution images using Wudalianchi as an example. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 153–162. Coconut Creek (Florida), ISSN 0749-0208. This paper constructs a composite classifier based on a convolutional neural network (CNN) and support vector machine (SVM) by using the decision fusion method to study the Wudalianchi Nature Reserve. It also conducts studies on the high-resolution remote sensing image classification of a lake wetland and makes a comparison between the pixel-based SVM method and the context-based CNN method. The experimental results show that the overall accuracy of the SVM-CNN classification method is higher than that of the SVM method, by 9% and 7.75% for the selected two study sites, and higher than the CNN method, by 5.23% and 2.39%. In particular, for the large-area lake wetland, the SVM-CNN classification method provides a higher boundary classification accuracy than the SVM and CNN methods. The research shows that the SVM-CNN composite classifier based on decision fusion theory provides a favorable means for the fine classification of lake wetland identification. [ABSTRACT FROM AUTHOR]

Hydrodynamic conditions are closely related to the development and dissipation of cyanobacterial blooms. The morphological features of Dolichospermum under different hydrodynamic conditions were analysed during three blooms in Gaoyang Lake, which is part of the backwater area of the China Three Gorges Reservoir, from 2007 to 2010. The results showed that the length of filaments and the morphology of cells were different in relation to the turbulence caused by the difference in hydraulic retention times. Thus, it was hypothesized that turbulence could shape the morphology and physiology of cyanobacteria. To answer the question regarding what the morphological and physiological responses of cyanobacteria to turbulent mixing mean for these organisms, laboratory experiments in continuous cultivation under different dilution rates were conducted to analyse the effects of specific turbulence intensity on the growth, nutrient uptake and morphology of Dolichospermum flos-aquae. Increasing the turbulence intensity caused synchronous increases in the ratio of the cellular length to the width, in the specific surface area of the filament and the cell and in the nutrient uptake rate; at the same time, the average filament length decreased. These indicated that the turbulence, within the range of our experimental design, could stimulate the growth of Dolichospermum by increasing its nutrient uptake. Additionally, at a high specific growth rate, the nutrient uptake rate of Dolichospermum changed more noticeably with the increasing morphological indicators, indicating that the rapidly growing Dolichospermum was more sensitive to turbulence. These findings explain the role of morphological strategies in the dominance of Dolichospermum within a certain range of turbulence intensity, especially in the early growth stage of blooms. The results also facilitate a greater understanding of the hydrodynamic effects on cyanobacteria and will be instrumental in developing flow regulation to control cyanobacterial blooms in reservoirs. Unlabelled Image • Field and laboratory studies were combined to explore the effect of turbulence on the morphology of Dolichospermum. • The hydraulic retention time influences the dominant phytoplankton species and cell morphology. • Turbulence promoted the growth of Dolichospermum by increasing the nutrient uptake due to morphological changes. • Rapidly growing Dolichospermum were more sensitive to the turbulence. • A useful reference for flow regulation to control cyanobacterial blooms in reservoirs is proposed. [ABSTRACT FROM AUTHOR]

Efficient transient simulation of large power grid is of great importance for system operation and dispatching, fault repetition, operator training etc. Online stability estimation and testing on system control and protection require hard real‐time performance of transient simulation. The conventional real‐time simulation, which splits an entire grid into sub‐grids and solves them in parallel, lacks generality for various case systems. This study proposes a new efficiency enhancement method without grid partitioning. Three key techniques are involved. First, parallel solving format is proposed to distribute two‐layer computational burdens into central processing unit cores in balance. Second, to calculate the fault changing the grid structure, the inverse current compensation is employed instead of re‐forming impedance matrix and repeating lower‐upper (LU) decomposition. Third, dual‐loop forward and backward substitutions to solve grid equations are modified to a single‐loop iteration, which further improves the computational efficiency. At last, the validity and effectiveness of the proposed method are verified by tests. [ABSTRACT FROM AUTHOR]

Cyanobacteria exhibit a variety of adaptive strategies that allow them to thrive in ever-changing aquatic environments. Here, successive steady states of continuous cultures were used to investigate the effects of quantified turbulence on the biochemical compounds and physiological processes of Anabaena flos-aquae in a photobioreactor under different dilution rates. A rapid increase in cell density was clearly observed following an increase in the turbulent dissipation rate at all growth rates of A. flos-aquae. The photosynthetic response to irradiance curves showed that the turbulence-treated strains exhibited lower photosynthetic oxygen evolution and saturating irradiance as well as higher respiration in rapidly growing young cells, indicating that they might not be very adaptable to high turbulent dissipation rates. Additionally, there was an increase in the protein levels of A. flos-aquae with increasing turbulence at all growth rates, whereas carbohydrate formation and lipid accumulation demonstrated the opposite trends. At a high growth rate, the level of carbohydrates decreased whereas that of lipids increased, which was interpreted as reflecting an adaptation to the turbulent environment. These findings suggest that turbulence sensitivity is shear regimen- and growth rate-dependent in A. flos-aquae. The high respiration capacity, low saturating irradiance, and conversion of carbohydrates to lipids represent effective measures for revealing the adaptive strategies of rapidly growing young cells under hydrodynamic regimes. The results regarding optimum lipid accumulation with specific growth traits have important implications for the design of cultivation methods of cyanobacteria resource utilization with respect to regulating turbulence. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel UL-ACB@Cu2+ is firstly successfully prepared as fluorescent probe for Spm and Spmd. • The "turn-on" probe UL-ACB@Cu2+ achieved selective detection toward Spm and Spmd in in human urine. • The LOD of the probe for Spm and Spmd are 0.156 μM and 0.762 μM. • The probe for Spm and Spmd is more convenient than the conventional methods in the analysis of real samples. Spermine (Spm) and spermidine (Spmd) are considered as potential biomarker for early diagnosis of human cancer. Herein, a novel acyclic cucurbituril derivative (UL-ACB) was firstly designed and synthesized, which fluoresces at 460 nm after excitation at 365 nm. UL-ACB is rich in oxygen atoms which are capable of forming coordinate bonds with copper (Cu2+) that cause quenching of UL-ACB fluorescence. Moreover, the addition of biological endogenous substances Spm and Spmd can turn on fluorescence of UL-ACB. Interestingly, the probe showed a remarkable detection efficiency for Spm and Spmd in human urine (the detection limits of Spm and Spmd were 0.156 μM and 0.762 μM, and the linear ranges are 0.156 ∼ 43.06 μM and 0.762 ∼ 29.10 μM), which completely covered the early diagnosis of urinary Spm (1 ∼ 10 μM) and urine Spmd (1 ∼ 20 μM) required concentration range in cancer patients. The probe for Spm and Spmd is simple, time-saving and selective, which may provide a new promising strategy for early cancer diagnosis. [ABSTRACT FROM AUTHOR]

Modular multilevel converters (MMCs) play a critical role in the future energy Internet pattern. Therefore, proper models for the simulation of complex systems with multiple MMCs are required. This study proposes a simplified equivalent model (SEM) based on the implicit trapezoidal method and Thevenin equivalent. The model can accurately simulate arm voltages of the MMC and is thus capable of simulating system‐level transients after faults and disturbances, circulating currents and subsynchronous oscillation components. Subsequently, a hybrid model combining SEM and a detailed equivalent model (DEM) is built to improve the overall simulation speed in scenarios where submodule‐level transients are mixed with system‐level ones. Finally, this study notes that the major difference between DEM and SEM results only from the voltage‐balancing cycle. An experiential formula is given to regulate SEM when the voltage‐balancing cycle is large, where the difference may become obvious/insufferable. [ABSTRACT FROM AUTHOR]

With the characteristics of large inertia, large time delay and time-varying parameters, it is difficult to control accurately the oil heating process in an oil-replenishing device for deep-sea hydraulic system. Four temperature control methods are presented and compared in this paper, i.e. proportional–integral–derivative controller(PID controller), fuzzy PID controller, Smith fuzzy PID controller and modified Smith fuzzy PID controller which adds a first order filter in the Smith predictor. They are simulated in MATLAB/SIMULINK based on the cases of transfer function matching and mismatching between the theoretical and the actual model. The results show that, in both cases, the step response curve of the modified Smith fuzzy PID controller has neither the significant oscillation nor the overshoot and requires the minimum time to achieve stabilization as well. Furthermore, this paper applies those four control methods in actual oil heating temperature control process through PIC16F877A micro controller unit (MCU). The experimental data demonstrate that the oil heating system controlled by the modified Smith fuzzy PID controller could stabilize at the expected temperature with nearly no overshoot, which further proves that the modified Smith fuzzy PID controller is able to sufficiently meet the challenges of industrial applications containing varying system parameters. [ABSTRACT FROM AUTHOR]

The rapid development of earth observation technology has produced large quantities of remote-sensing data. Unsupervised classification (i.e. clustering) of remote-sensing images, an important means to acquire land-use/cover information, has become increasingly in demand due to its simplicity and ease of application. Traditional methods, such as k-means, struggle to solve this NPhard (Non-deterministic Polynomial hard) image classification problem. Particle swarm optimization (PSO), always achieving better result than k-means, has recently been applied to unsupervised image classification. However, PSO was also found to be easily trapped on local optima. This article proposes a novel unsupervised Levy flight particle swarm optimization (ULPSO) method for image classification with balanced exploitation and exploration capabilities. It benefits from a new searching strategy: the worst particle in the swarm is targeted and its position is updated with Levy flight at each iteration. The effectiveness of the proposed method was tested with three types of remote-sensing imagery (Landsat Thematic Mapper (TM), Flightline C1 (FLC), and QuickBird) that are distinct in terms of spatial and spectral resolution and landscape. Our results showed that ULPSO is able to achieve significantly better and more stable classification results than k-means and the other two intelligent methods based on genetic algorithm (GA) and particle swarm optimization (PSO) over all of the experiments. ULPSO is, therefore, recommended as an effective alternative for unsupervised remote-sensing image classification. [ABSTRACT FROM AUTHOR]

Three ferrocene analogues, D (η-CBH)M (M = Fe, Co, and Ni), with triplet aromatic CBH ligands have been predicted at TPSSh/6-311+G(d,p) level. We find that the M atom interacts drastically with the two CBH ligands through a nearly fully-filled 3d subshell, which is different from (η-CH)Fe. The natural population analyses suggest that (η-CBH)M have an unconventional charge distribution, i.e., the M atom is negatively charged, while the two boron rings are positively charged. The analyses of the electronic and dynamic stabilities indicate that (η-CBH)Co is the most stable among (η-CBH)M. Thus, we theoretically confirm that the triplet aromatic CBH cluster can be regarded as a potential new ligand. Our theoretical predictions are awaiting future experimental verification. [ABSTRACT FROM AUTHOR]

A method of diminishing the shape error of membrane mirror is proposed in this paper. The inner inflating pressure is considerably decreased by adopting the pre-shaped membrane. Small deformation of the membrane mirror with greatly reduced shape error is sequentially achieved. Primarily a finite element model of the above pre-shaped membrane is built on the basis of its mechanical properties. Then accurate shape data under different pressures can be acquired by iteratively calculating the node displacements of the model. Shape data are applicable to build up deformed reflecting surfaces for the simulative analysis in ZEMAX. Finally, ground-based imaging experiments of 4-bar targets and nature scene are conducted. Experiment results indicate that the MTF of the infrared system can reach to 0.3 at a high spatial resolution of 10l p/mm, and texture details of the nature scene are well-presented. The method can provide theoretical basis and technical support for the applications in lightweight optical components with ultra-large apertures. [ABSTRACT FROM AUTHOR]

Unsupervised image classification is an important means to obtain land-use/cover information in the field of remote sensing, since it does not require initial knowledge (training samples) for classification. Traditional methods such as k-means and Iterative self-organizing data analysis technique (ISODATA) have limitations in solving this NP-hard unsupervised classification problem, mainly due to their strict assumptions about the data distribution. The bee colony optimization (BCO) is a new type of swarm intelligence, based upon which a simple and novel unsupervised bee colony optimization (UBCO) method is proposed for remote-sensing image classification. UBCO possesses powerful exploitation and exploration capacities that are carried out by employed bees, onlookers, and scouts. This allows the promising regions to be globally searched quickly and thoroughly, without becoming trapped on local optima. In addition, it has no restrictions on data distribution, and thus is especially suitable for handling complex remote-sensing data. We tested the method on the Zhalong National Nature Reserve (ZNNR) - a typical inland wetland ecosystem in China, whose landscape is heterogeneous. The preliminary results showed that UBCO (overall accuracy = 80.81%) achieved statistically significant better classification result (McNemar test) in comparison with traditional k-means (63.11%) and other intelligent clustering methods built on genetic algorithm (unsupervised genetic algorithm (UGA), 71.49%), differential evolution (unsupervised differential evolution (UDE), 77.57%), and particle swarm optimization (unsupervised particle swarm optimization (UPSO), 69.86%). The robustness and superiority of UBCO were also demonstrated from the two other study sites next to the ZNNR with distinct landscapes (urban and natural landscapes). Enabling one to consistently find the optimal or nearly optimal global solution in image clustering, the UBCO is thus suggested as a robust method for unsupervised remote-sensing image classification, especially in the case of heterogeneous areas. [ABSTRACT FROM AUTHOR]

The electrical load is one of the most important parts of power systems. Parameter identification of load model is critical for power system stability analysis. The composite load model, which comprises a static load and a dynamic load, is one of the most widely used models in power system simulation and control. As the load characteristics could change considerably over time, online parameter identification is needed. However, because of the non‐linearity and complexity, online parameter identification for load models remains difficult to achieve, and there is rarely an effective solution. This study proposes a load model simplification and parameter identification method to solve this problem. First, the composite load model is preliminarily simplified by choosing the dominant parameters. Next, the load model is further simplified based on a second‐ordered state equation of the induction motor. Subsequently, a two‐step method for online parameter identification is presented. The first step is the electrical parameter identification based on the multi‐layer searching method proposed in this study. The second step is the mechanical parameter identification via the Newton method. Finally, an example for a typical case system is presented to demonstrate the effectiveness, efficiency and accuracy of the two‐step method. [ABSTRACT FROM AUTHOR]

• UiO-66 (Zr/Ti) was used to catalyze the synthesis of PET for the first time. • Through chemical process optimization, PET with a lower b value was successfully synthesized in a 5 L reactor, which provided inspiration for MOF materials in industrial catalysis. • The DFT calculations revealed that the reaction path of UiO-66(Zr/Ti) was more suitable for the coordination of the carboxy oxygen atom mechanism, and the reaction activation energy of 22.37 kacl/mol was close to that of the Sb-based catalyst. PET (poly(ethylene terephthalate)) is one of the most important type of thermoplastic polyesters and widely used in various fields. Titanium-based catalysts are environmentally friendly and have higher catalytic activity than antimony-based catalysts when used in industry. However, titanium-based catalysts are prone to hydrolysis and result in discolored products. UiO-66 (Zr/Ti) with different Ti4+ contents were successfully synthesized via one-step method. The material was characterized by XRD, SEM, FT-IR, XPS, BET and TG techniques. The results demonstrates that Ti4+ was integrated into the UiO-66 framework. NH 3 - in situ DRIFTS, pyridine-IR, and NH 3 -TPD were used to explore the acidic properties of the samples, which proved that stable Lewis acidic sites are present in the samples even at 300 °C. The catalytic performance of UiO-66 (Zr/Ti) containing different Ti4+ was explored under different conditions. At the same time, the scale-up experiment was carried out in a 5 L reactor, and the PET chips obtained had a lower b value. The catalytic reaction mechanism of UiO-66(Zr/Ti) was demonstrated by DFT calculations and the catalytic performance was close to Sb-based catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Modified S transform (MST) and Extreme Learning Machine (ELM) algorithms are developed and are applied to power quality (PQ) analysis. Two adjustable parameters are introduced in MST to control the Gaussian window width, free from the limitation of time–frequency resolution in the standard S-transform (ST) with an uncontrollable window. Compared with ST, MST provides more convenient means for achieving desired time–frequency resolution for various PQ disturbances signals. In order to optimize the adjustable parameters, three optimization indexes are introduced to make the optimization process more adaptively. Based on the time–frequency matrix of MST, four disturbance features are enough to construct the feature vector, solving the problem of the statistical feature redundancy. Compared with the algorithms such as Back Propagation Neural Network (BPNN) and the Support Vector Machine (SVM), ELM has the advantages of simple structure, fast training speed and high precision, more suitable for engineering application. The simulation experiments show that the MST-ELM algorithms, could provide higher classification accuracy, better anti-noise property, less computational cost and independent of training set. [ABSTRACT FROM AUTHOR]

In the face of complicated, diversified three-dimensional world, the existing 3D GIS data models suffer from certain issues such as data incompatibility, insufficiency in data representation and representation types, among others. It is often hard to meet the requirements of multiple application purposes (users) related to GIS spatial data management and data query and analysis, especially in the case of massive spatial objects. In this study, according to the habits of human thinking and recognition, discrete expressions (such as discrete curved surface ( DCS), and discrete body ( DB)) were integrated and two novel representation types (including function structure and mapping structure) were put forward. A flexible and extensible ubiquitous knowledgeable data representation model (UKRM) was then constructed, in which structurally heterogeneous multiple expressions (including boundary representation (B-rep), constructive solid geometry (CSG), functional/parameter representation, etc.) were normalized. GIS's ability in representing the massive, complicated and diversified 3D world was thus greatly enhanced. In addition, data reuse was realized, and the bridge linking static GIS to dynamic GIS was built up. Primary experimental results illustrated that UKRM was overwhelmingly superior to the current data models (e.g. IFC, CityGML) in describing both regular and irregular spatial objects. [ABSTRACT FROM AUTHOR]

This paper proposes a design method for cross-spring pivots with quasi-constant rotational stiffness in the field of unbalanced moment measurement. To achieve high precision measurement of unbalance moment, the relationship between instrument sensitivity and the rotational stiffness of the cross-spring pivot is revealed. In order to eliminate the impacts of payload changes on instrument sensitivity, the relationship between geometric parameters and the rotational stiffness of the pivot is studied. Further, cross-spring pivots with quasi-constant rotational stiffness are designed as the rotation unit of a static balancing instrument, while the center shift of pivot takes the minimum value. Certain amount of unbalance moments is measured by the instrument. Experimental studies of the instrument show that the maximum measurement errors of unbalance moments 0.162 g mm, 0.319 g mm and 1.300 g mm are 0.068 g mm, 0.086 g mm and 0.053 g mm, respectively, when the payload ranges from 0 g to 7000 g. The instrument can achieve a relatively high precision measurement and the instrument sensitivity is almost not affected by the changes of payloads. The effectiveness of the method and the stiffness property of the pivot are verified by the experiments. So this kind of pivot has good prospects in unbalance moment measurement. [ABSTRACT FROM AUTHOR]